Mandisa-Maia Jones-Haywood, MD

• Assistant Professor
• Anesthesiology
• Wake Forest University School of Medicine
• Winston Salem, North Carolina

Noninferiority trials and equivalence trials are similar birth control pills 28 days mircette 15 mcg fast delivery, but equivalence trials are two-sided studies birth control pills libido mircette 15 mcg cheap, where the study is powered to detect whether the new treatment is not worse and not better than the existing one birth control pills dangers purchase discount mircette on line. In noninferiority studies birth control 6 weeks buy mircette 15 mcg free shipping, the researchers must prespecify the difference they intend to detect birth control pills questions and answers discount mircette 15 mcg amex, known as the noninferiority margin, or irrelevant difference or clinical acceptable amount. This margin is determined by clinical judgment combined with statistical factors and is used in the sample size and power calculations. For example, is a difference of 4% in infection rates between two groups large enough to sway your decision about antibiotics These decisions are based on clinical factors such as severity of the disease, and variation of the outcomes. The noninferiority question in this study was that the blood substitute product would be used in scenarios in which blood products were needed but not available or permissible. Incidentally, this is another example of where adaptive power analysis was performed after enrollment of 250 patients to ensure that no increase in the trial size was necessary. Once a study has a significant difference, questions about statistical power are irrelevant. Association and Causation Most studies will describe associations between outcomes and effects of interest. Whether these associations represent a cause-effect relationship is often an issue. A useful Chapter 63 Critical Appraisal of Trauma Research 1203 tool to make this determination is the set of nine criteria proposed by Sir Austin Bradford Hill in 1965, which still proves to be useful as a guideline. Strength of the association: this criterion does no equate to size of the p-value; rather it refers to the effect size. Consistency: the results have been replicated under different conditions by independent investigators. Specificity: the effect of interest is associated with a specific outcome rather than a wide range of outcomes. Its presence can help the case for a causal effect, but its absence does not discard it, as most outcomes have multifactorial, interdependent causes. Temporality: There is a clear temporal relationship in which the effect of interest precedes the disease. Although this may seem obvious, it is important that we take into account how the outcomes and the effect are measured. Biological gradient or dose response: Increasing/decreasing exposure is associated with increasing/decreasing risk of disease. Plausibility: Although novel findings may not fit this criterion, when there is a proposed scientific mechanism that can explain the association, the case for causation is strengthened. Yet there is no denying that if the reported finding does not fit with current knowledge, there is a tendency toward a healthy skepticism. Experimental evidence: Hill proposed that "Causation is more likely if evidence is based on randomized experiments. However, as Rothman and Greenland indicated, we must be careful in the application of this criterion: "Whatever insight might be derived from analogy is handicapped by the inventive imagination of scientists who can find analogies everywhere. At best, analogy provides a source of more elaborate hypothesis about the associations under study; absence of such analogies only reflects lack of imagination or lack of evidence. Chance is dealt with by statistical testing, while appropriate designs and analytic techniques can assist with eliminating or minimizing bias and confounding. Bias is the deviation of results due to systematic errors in the research methods. Although there are several different names for biases, two types seem to capture most the biases presented in surgical literature: (1) selection bias, which occurs when the study groups differ systematically in some way or when the study sample differs from the study population; and (2) observer/information bias, which occurs when there are systematic differences in the way information is collected for the groups being studied. The article by del Junco et al80 on the "seven deadly sins in trauma outcomes research" is an excellent review of some of the most common biases. There are several types of selection bias that commonly appear in the trauma literature. The panel was charged with proposing appropriate study designs and follow-up methods to reduce missing data and appropriate statistical methods to address missing data for analysis of results. The most important things to consider about missing data are (1) the proportion of patients with missing data; and (2) whether the data are missing at random, thus not biasing the results in a significant way, or whether there is some pattern that can bias the results. Let us illustrate this with a little story: the father 1204 Section V Management of Complications After Trauma of one of the authors (Sauaia) was a physician interested in congenital heart defects. He was conducting a populationbased study about the incidence of such defects in schoolage children and visited several schools, screening children for heart defects. At the end of the day, this young researcher considered the absent children (his missing data) for a moment and, wanting complete data, decided to visit them at home. This made sense, as these ill children were more likely to miss school because of symptoms or medical appointments. Missing data not at random in trauma occur for two radically different reasons: (1) patients are too sick to have the test (eg, died early, intravenous access not possible, chaotic trauma scene, etc), in which case, adverse outcomes are common; or (2) patients are not sick enough to justify the test (ie, early discharge, hemodynamically stable, not on mechanical ventilation, etc), in which case, adverse outcomes are rare. We then addressed the missing data using two analyses: the first included only patients for whom lactate was measured; the second included all patients and used a "missing indicator" for unavailable lactate levels (ie, each patient was assigned three possible values for lactate: missing, normal, and abnormal). The results of the two analyses were remarkably similar and increased the strength of their findings. In a more recent example, Odom and colleagues83 addressed this issue in their study on the value of lactate as a predictor of trauma mortality. They astutely observed that the selection bias created by the missing lactate values would bias their results toward the null hypothesis rather than the positive effect they found. Many methods are available to deal with missing data, such as the "last value carried forward. In simple words, this method imputes missing values based on regression equations derived M times, followed by an analysis of each imputed dataset and finalized by a combination of the M analyses. This occurs when the individual does not survive long enough to have the "opportunity" to receive the complete intervention. These early nonsurvivors contribute to increasing the mortality rate of the group not receiving the intervention, artificially inflating the effect of the intervention. However, truth be told, one can never know what would have happened to nonsurvivors had they survived long enough to get the intervention. One can also add a time-varying covariate to the survival analysis, which is a variable that, as the name says, varies over time. For example, the ratio of blood products varies hour to hour during the dynamic resuscitation period. The big difference here is that the first patient experienced the 2:1 ratio at all times while the second had an initial ratio of 3:0 followed by a 0:3. This may be a solution, but it limits the generalizability, as the study findings apply only to patients who survive the acute post-injury period. Other types of commonly encountered selection biases are-loss to follow-up not at random (eg, patients failed to return to follow-up visits due to long-term injury-related complications), refusal to participate or withdrawal due to side effects or invasiveness of the intervention, consent not obtained due to traumatic brain injury, etc. This is a good reminder to always read the inclusion and exclusion criteria to determine whether they resulted in selection bias. Common exclusion criteria that may limit the generalizability of the investigation are: advanced age, comorbidities, early deaths or incomplete data. It is important to emphasize the findings apply only to the population that fits both the inclusion and exclusion criteria. Another type of common bias in surgical research is intervention bias, defined as using an intervention to define a population or group as opposed to preintervention risk factors. Therefore, it is important that the investigators are certain that the matching variable is of no interest in the analysis of the outcomes. Interactions and Effect Modification In confounding, variable A is responsible for part or all the association between variables B and C, and we want to adjust for it (in other words, minimize its effect) to be able to assess the association between B and C. Conversely, in effect modification or interaction, variable A modifies the association between B and C. This type of association must be described, not adjusted for, as it provides important information of the mechanism underlying the association of B and C. Thus, when appraising multivariate models, the reader should make sure pertinent interactions were tested and, if significant, described appropriately. An example of an important interaction can be found in our study on the effect of pre-injury antiplatelet therapy on post-injury outcomes. The most quoted example is the association of coffee drinking and lung cancer, which is confounded by the real culprit, smoking, a variable associated with both coffee drinking and lung cancer. To be considered a confounder, a variable must be associated with both the outcome and the effect of interest (ie, a risk factor or an intervention). In trauma, injury severity, age, and comorbidities are frequent confounders of the association between an intervention and the outcome. Appropriately so, readers should not find p-values in this table, as any differences in the distribution of these confounders are, by definition, a result of chance. Randomization, in general, increases the likelihood of similar distribution of confounders, which then are not associated with group membership, allowing us to assess the effect of the intervention (the main difference between the two groups) on the outcome. Surgical and emergency interventions, however, are often not amenable to blinding. Using this propensity score, we can choose matching control patients, that is, patients who did not receive the intervention despite having the same propensity score as the patients who received the intervention. The downside of this procedure is that the reason why patients did not receive the intervention despite having the same propensity score is often unknown, or due to unmeasured variables that may have an effect themselves on the outcomes. Finally, matching limits the ability of the investigators to examine the effects of the Descriptive Statistics Descriptive statistics, such as mean and standard deviation, median and interquartile range, frequency, and percentages, are used to provide the reader with the best possible description of the sample. Since the reader does not have access to the raw data, it is up to the authors to provide readers with a clear picture of what the sample looked like. Are they similar enough that one may directly apply the findings, or are they older, younger, more severely injured, etc Categorical variables, such as sex and blunt versus penetrating mechanism, are expressed as frequency (N) and percentages. When the variable distribution is normal, symmetric, medians and means are identical. However, when the variable is skewed or there are outliers, medians, rather than means, are better descriptors. Data dispersion for normally distributed variables is usually represented by the standard deviation (68% of the data should be contained within mean ±1 standard deviation, 95% of the data within mean ±2 standard deviations), while for skewed data we most commonly use the interquartile range (the lower and upper quartile; 50% of the data are contained within this interval) or the range (maximum and minimum values). Inferential Statistics Studies will usually present initially bivariate analysis (sometimes called univariate). This consists of an unadjusted, crude comparison between two (or more) groups of subjects. The main point for readers in this part of the article is to pay attention to variables that can be confounders, that is, variables with different distribution between the groups (thus associated with group membership) and also associated with the outcome. This difference does not need to be statistically significant, as the sample may be small thus prone to a type 2 error. Deciding whether a variable may be playing a confounder role is a clinical, not a statistical decision. After examining this table, the reader can decide which ones are potential confounders. Analytic techniques that minimize confounding are stratification and multivariate analysis. Stratification may work when there are just a few risk factors and a large sample size. For example, in order to account for the confounding effect of smoking in the association between coffee drinking and lung cancer, one may stratify the analysis on smoking status and observe whether the association between coffee drinking and lung cancer holds within each stratum. Multivariate analyses are basically an advanced form of stratification done on multiple variables. There are several types of multivariate models depending on the distribution of the outcome. Binary outcomes (eg, death yes or no) are commonly addressed using logistic regression. Categorical outcomes with more than two strata can be analyzed with polytomous logistic regression. When time to event is of interest or there is need to censor data (eg, patients who died or are discharged before experiencing the outcome of interest), survival analysis is an option. Linear regression assumes that the outcome is continuous, has a distribution not too far from normal, and has, as the name says, a linear relationship with the covariates. When these assumptions are not applicable (eg, outcome is categorical or too skewed), then we may apply a larger category of models, named generalized linear models. Please, note that there is a difference between generalized linear models and general linear models. The economic analysis by Schwartz and colleagues93 on delays in laparoscopic cholecystectomy is an example of a study using a generalized linear model. The generalized linear models are a broad class of models that include the logistic regression, the Poisson regression, log-linear models, gamma-distribution models (as used in the above mentioned article) and others. The description of generalized linear models usually includes the term "link," which is a function linking the actual outcome Y to the estimated Y in a model. In simple words, it is the transformation done to the outcome variable to convert it to continuous. In a logistic regression, the transformation or link used is called the logit and the distribution is binomial, that is, a yes or no type of variable. For the gamma model (used in the Schwartz et al paper93), the link is the log, and the distribution is right-skewed with a variation that increases with the mean. This type of model is often used in econometrics because it fits the distribution of cost in health care, that is, care for most patients results in little costs, but a few patients require very costly treatments. In the log-linear and the Poisson regression, the link is a log and the distribution is the Poisson distribution. Poisson regression is usually applied to count data, for example, number of trauma deaths over a period of time, as seen in a 2013 article by Kahl et al assessing time-trends in annual trauma mortality rates. For example, the Cox-proportional regression model, a type of survival analysis, requires, as the name says, that the risks are proportional, that is, do not vary over time. Variation over time is not an insurmountable problem and can be tested for and remedied by introducing time-varying covariates in the model.

Adverse effects can be reversed if necessary with careful titration of the opioid receptor antagonist naloxone birth control shot generic 15 mcg mircette with mastercard. Naloxone must be administered with care as access effect is associated with undesirable hemodynamic effects such as hypertension birth control 10 years mircette 15 mcg order visa, tachycardia birth control for women limited cheap mircette 15 mcg without prescription, and myocardial ischemia as well as acute pulmonary edema birth control for discharge generic mircette 15 mcg on-line. Morphine is also associated with a non-receptor-associated effect of histamine release birth control for women 2 generic mircette 15 mcg without prescription, and this can result in undesired hypotension, tachycardia, and possibly exacerbating bronchospasm in patients with reactive airway disease. Prolonged use of morphine, especially in renal impairment, can result in the accumulation of a metabolite, morphine-6 glucuronide, and may result in a prolonged sedative effect. Fentanyl is a lipid-soluble synthetic opioid having a more rapid onset of action than morphine. When large doses are administered, especially by continuous infusion, termination of effect requires elimination, probably due to the saturation of poorly perfused adipose tissue. The pharmacokinetics of fentanyl is not much altered by the presence of cirrhosis, and clearance appears to remain normal in renal failure. Hemodynamically fentanyl maintains cardiovascular stability and does not have significant negative inotropic effect. In the presence of high sympathetic tone, fentanyl may decrease blood pressure indirectly by decreasing central sympathetic output. Fentanyl also predictably causes a decrease in heart rate by a central vagotonic effect. The receptor-associated side effects of fentanyl and their management are the same as described for morphine. Fentanyl is 10 times more potent than morphine and has a more rapid onset of action, requiring vigilance with its use. Unlike morphine, fentanyl does not release histamine and therefore may be a better choice in patients who are hemodynamically unstable or who have reactive airway disease. Hydromorphone appears to have minimal hemodynamic effect and does not result in release of histamine. Like morphine and fentanyl, hydromorphone is inexpensive, and is recommended as a third-line agent after morphine and fentanyl. Weaning of patients from mechanical ventilation is often hampered by oversedation. The provision of anxiolysis and amnesia are of major importance for critical care patients undergoing intermittently painful procedures or mechanical ventilation. It has been demonstrated that the majority of patients surviving prolonged mechanical ventilation found memory of the experience to be unpleasant. Recent recommendations suggest the use of propofol or dexmedetomidine and reduced use of benzodiazepines for routine sedation due to a possible increased risk of delirium and mortality. Characteristics of commonly used benzodiazepines, dexmedetomidine, and propofol are found in Table 55-7. Propofol is a lipid-soluble alkyl phenol intravenous anesthetic that is insoluble in water and formulated in a lipid emulsion. It has hypnotic, amnestic, and antiemetic properties but is devoid of analgesic effect. The sedative effect is rapid and predictable and recovery occurs quickly when the drug is terminated. Compared to benzodiazepines duration of mechanical ventilation is significantly shorter (2. No respiratory depression-consider for patient failing spontaneous breathing trial due to agitation/anxiety. Risk of propylene glycol toxicity with high doses (anion-gap acidosis, serum creatinine, lactate). Lorazepam is associated with increased risk of delirium and should be avoided in elderly and mechanically ventilated patients. Midazolam is associated with increased risk of delirium and should be avoided in elderly and mechanically ventilated patients. A lipid solution of propofol also supports rapid bacterial growth at room temperature, and a number of postoperative bacteremias had been linked to poor administration technique. Dexmedetomidine is an imidazole compound that is a highly selective agonist of the 2-adrenergic receptor with eight times greater affinity than clonidine. Initially evaluated as an anesthetic, it was found to be associated with excess bradycardia and hypotension. Patient selection and proper drug infusion are needed to avoid significant hemodynamic effects. Avoiding the initial bolus dose can reduce the incidence of significant bradycardia and hypotension on administration. Dexmedetomidine produces sedation but easy arousal, analgesic-sparing effect, and minimal depression of the respiratory drive. These characteristics are unique in that patients appear to be sedated but are readily roused and interactive and can follow commands. This makes the drug highly suited for patients who are being weaned from the ventilator, especially those who become agitated when other sedation is reduced. A recent study of early mobilization during daily awakening in 104 mechanically ventilated patients demonstrated increased independent functional status at hospital discharge, shorter duration of delirium, and fewer ventilator-free days during the 28-day follow-up period than those observed in controls. Patients in the "no sedation" group were allowed morphine boluses and had frequent nonpharmacologic antianxiety interventions such as reassurance by nurses and reassessment by physicians of pain orders and the need for tubes and catheters. It may occur in up to 54% of patients and can be further defined as (1) hyperactive delirium: characterized by hypervigilance, restlessness, anger, irritability, and uncooperativeness, and is associated with better overall outcomes; (2) hypoactive delirium: the more common and deleterious, characterized by a lack of awareness, decreased alertness, sparse or slow speech, lethargy, decreased motor activity, and apathy; and (3) mixed delirium: apparent in patients with a mixed clinical picture. Hypoactive delirium may be mistaken for depression or stupor and therefore is often not recognized which may contribute to higher 6-month mortality 32. Preexisting risk factors for delirium include cognitive impairment, chronic illness (including hypertension), age greater than 65 years, depression, smoking, alcoholism, and severity of illness. Risk factors arising during hospitalization include congestive heart failure, sepsis, prolonged restraint use, immobility, withdrawal from substance abuse, seizures, dehydration, hyperthermia, head trauma, intracranial mass lesions, and the use of lorazepam, midazolam, morphine, fentanyl, and propofol. The scales have midrange scores that indicate a calm, cooperative patient with high and low scores indicating excess agitation or oversedation. A common sedation scale should be used throughout the institution for consistent and effective use. Daily awakening trials are most effective when following a standardized nurse-driven protocol. Haloperidol has been associated with a reduced seizure threshold, extrapyramidal reactions (dyskinesia), and laryngeal dystonia. In patients with hypoactive delirium, the dose of haloperidol may need to be reduced. Oral agents are longer acting and include aripiprazole, risperidone, or oral haloperidol. There is increasing public awareness of this issue; preventable complications are often reportable to regulatory authorities and many insurers, including Medicare, may refuse to pay hospital or physician charges in case of patients with certain preventable critical care complications. The need to reduce preventable complications of critical care has resulted in a number of guidelines released by professional and regulatory organizations and local hospitals. Electrophysiologic evaluation of muscle and nerve function is important for the diagnosis. Although not conclusive, available data suggest that the avoidance of long-term use of neuromuscular blocking agents (eg, pancuronium and vecuronium), particularly in combination with corticosteroids or aminoglycoside antibiotics, may be an important preventative measure. Follow-up electromyographic studies have shown changes with chronic neurogenic damage, however. End of life and goals of care discussions (see below in this chapter) are also particularly important in this patient population. Sepsis and subsequent multiple organ system failure cause most late deaths following trauma in the elderly. Urosepsis and pneumonia are common in elderly trauma patients and what would be otherwise a relatively simple problem to treat in the young healthy individual may be the trigger to a cascade of events in the elderly patient, which may culminate with multiple organ dysfunction and death. For these reasons, aggressive and early treatment of these infections, initially with broad-spectrum antibiotics followed by culturebased deescalation or adjustment of therapy, is a critical determinant of good outcome. One of the most common causes of death in the geriatric trauma population is pneumonia following blunt chest trauma and rib fractures. Due to decreased pulmonary reserve and associated comorbidities, the elderly trauma patient is generally more susceptible to the development of pneumonia due to an inability to effectively clear secretions and take deep breaths. To this end, patient-controlled narcotic analgesia and/or epidural administration of opiate analgesics or local anesthetics (rib blocks or chest wall pain catheters) may be helpful in appropriately selected trauma patients. Another option is surgical stabilization of rib fractures, but indications are not agreed upon, and data to date have not been able to demonstrate a consistent outcomes benefit. Critical Illness Polyneuropathy Prolonged neuromuscular weakness associated with critical illness was reported as early as the 1950s. The syndrome is characterized by the development of diffuse neurogenic muscle weakness over a several-week course of severe critical illness. The neurologic manifestations may include unexplained failure to wean from mechanical ventilation, decreased/absent deep tendon reflexes, tetraparesis, muscle atrophy, decreased fibrillations, compound muscle action potentials, and axonal damage on electrophysiologic testing. Nerve conduction velocities are near normal, and histologic evaluation of peripheral nerves has shown acute diffuse neurogenic atrophy in muscles and axonal degeneration in nerve tissue. More recently, trauma centers in the United States have experienced an epidemic of elderly falls. The main clinical trials on anticoagulant therapies rarely include the frail elderly; however, many such patients arrive after taking these drugs. Even patients with mild to moderate traumatic brain injury are at a much higher risk of developing fatal intracranial hemorrhage due to the use of these drugs and because of "increased space" for hematoma expansion due to brain atrophy. Missed Injuries the initial evaluation of the trauma patient centers on recognizing abnormal physiology and the pattern of injury. Missed injuries are the most common cause of preventable death; however, the true incidence of missed injury is difficult to determine. Surgical intensivists caring for trauma patients must recognize potential injuries likely to occur given a particular mechanism. The challenge becomes the rapid identification of occult injuries before the clinical condition of the patient deteriorates. Another situation in which the urinary output will be misleadingly elevated is in the setting of hyperglycemia. Whether the patient is a diabetic or he or she has received high-dose steroids for a spinal cord injury, the resultant hyperglycemia will cause a misleadingly comforting urinary output. A serum blood sugar over approximately 180­190 mg/dL results in glycosuria and this pitfall must be recognized. The etiology of metabolic acidosis in the injured patient is, until proven otherwise, due to hypoperfusion from hemorrhagic shock; it must be understood, however, that the base deficit can be due to ketosis, nonanion gap acidosis including hyperchloremia due to excess saline infusion and sepsis. Hypoxemia and Pulmonary Contusion Parenchymal disease is the most common cause of hypoxemia (see Chapter 57). Pulmonary contusion consists of a direct injury to the lung the contusion evolves over the first 24 hours as alveolar hemorrhage and edema accumulate, such that the Po2 progressively decreases during that time period. The contused lung has leaky capillaries and aggressive fluid resuscitation, particularly with colloids, may result in further deterioration of pulmonary function. The biggest pitfall in the management of pulmonary contusions is failure to anticipate injury progression. It is a common pitfall to ignore such an episode, and assume that resuscitation has been completed and hypotension is due to other causes such as traumatic brain injury or bleeding due to long bone fractures. There are certain injuries that may require ongoing resuscitation with blood products, most prominent among them a vertical shear-type posterior element pelvic fracture (see Chapter 35). However, in the absence of any such known injury, a diligent attempt must be made to exclude a missed injury in the abdomen or perhaps an injury whose magnitude was underestimated. Severe sepsis includes sepsis and organ dysfunction, while septic shock encompasses severe sepsis accompanied by hypotension and hypoperfusion, refractory to volume replacement and requiring inotropes. It is extremely rare for a patient to have septic shock early, unless there is an obvious infection, such as an aspiration pneumonia or perforated viscus. The patient who has leukocytosis with bandemia, fever, and clinical deterioration must be investigated closely for a source of infection. The diagnosis of an infection following major trauma is the biggest pitfall since the cardinal signs of infection such as fever, leukocytosis, and hyperdynamic hemodynamic state can, and frequently are, the result of the inflammatory cascade in response to tissue trauma. The consequences of liberal use of antibiotics to broadly cover for presumptive sepsis are real, including drug resistance, antibiotic-related colitis, and fungemia. The consequences of not treating a patient with fever, hyperdynamic state, and signs and symptoms of infection, in the absence of positive cultures or a clear source, are equally daunting, as the patient may indeed be harboring an infection, but the yield of blood cultures and the other surveillance tests are poor. The optimal management of septic complications is prevention, the Surviving Sepsis campaign provides a bundle of prophylactic and treatment measures to reduce the incidence and impact of sepsis. The initial treatment for acalculous cholecystitis is conservative (bowel rest, antibiotics, and intravenous fluids), although some patients will require operative intervention. Alternatively, for those patients who are too sick to tolerate an operation, a percutaneous cholecystostomy tube placement is the best option. Ethical Principles Applicable to Medical Decision Making Ethical decision making should involve the careful application of established principles. With the possible exception of the principle of distributive justice, each of the following principles should be applied in any given decision-making process: · Beneficence: the principle of "doing good" as applies to a particular patient, individual, or situation. This last principle typically involves decisions regarding the distribution of scarce resources to allow the "optimum" treatment of not a single individual, but a population of individuals (society). Such a principle may apply during wartime casualty triage or civilian mass-casualty triage. Changes in gastrointestinal motility, characterized by increased gastric residuals and intolerance to enteral nutrition, imply the onset of an infection and one potential source of such infection is the gallbladder. Acalculous cholecystitis is a disease of the critically ill patient; most of these patients have had major trauma or extensive burns, or are recovering from major surgery. The diagnosis can be difficult because patients who develop acalculous cholecystitis tend to be critically ill or severely injured and are frequently unable to react to physical examination. Specific criteria that may allow withdrawal/withholding include the following: · Provision of further treatment is considered medically futile with respect to achieving well-defined therapeutic goals. This may be obtained from family, friends, or other providers with a history of relevant contact with the patient. The concept of futility is central to initial withdraw/withhold support decisions.

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Since the retroperitoneal tissue is often thin in young patients birth control otc order mircette no prescription, it may be worthwhile to cover an extensive aortic repair or the suture line of a prosthesis with mobilized omentum before closure of the retroperitoneum birth control for women xxy purchase 15 mcg mircette with mastercard. An alternate approach is to mobilize the gastrocolic omentum off the left side of the transverse colon and then bring the mobilized pedicle around the ligament of Treitz to once again cover the aortic repair or graft birth control pills menstrual cramps cheap mircette 15 mcg on line. This vascularized pedicle of omentum should prevent a postoperative aortoduodenal fistula birth control pills and antibiotics mircette 15 mcg purchase. While the vast majority of injuries to the infrarenal aorta are penetrating in nature birth control pills 2015 generic mircette 15 mcg on-line, a small number occur after blunt trauma. In the aforementioned review of 62 cases of blunt aortic trauma prior to 1997 reported by Roth et al, motor vehicle collisions accounted for 57% of the cases and 47% of the total were directly attributed to lap belts. In the one series published in 2001 in which injuries to the suprarenal and infrarenal abdominal aorta were separated, the survival rate in the infrarenal group was only 34. Survival after retrohepatic injury is rare, with only one survivor in the most recent series. Note extensive fat necrosis related to associated injury to the head of the pancreas. Survival to hospital discharge was 41%, and 1-year follow-up was available in seven of nine survivors and no patient had more than trace lower extremity edema. In the abovementioned series, three patients underwent ligation of the suprarenal inferior vena cava with only one long-term survivor. One-year follow-up in this patient revealed minimal lower extremity edema and normal renal function. If the hematoma is not rapidly expanding and there is no free intraabdominal bleeding, some surgeons will loop the ipsilateral renal artery with vessel loops or a vascular tape in the midline at the base of the mesocolon. It should be noted that obtaining proximal vascular control prior to exploration of a perirenal hematoma is controversial. Indeed, in one study, preliminary vascular control of the renal hilum had no impact on nephrectomy rate, transfusion requirements, or blood loss. The surgeon should simply open the retroperitoneum lateral to the injured kidney and manually elevate the kidney directly into the wound. A large vascular clamp can be applied proximal to the hilum either at the midline on the left or just lateral to the inferior vena cava on the right to control any further bleeding. Patients who present after blunt trauma may have either a renovascular or renal parenchymal injury, also. Patients in the former group, however, generally present with renovascular occlusion, which will be discussed below. Renovascular Injuries: Renal Artery Renovascular injuries are difficult to manage, especially when the renal artery is involved. It is an extraordinarily small vessel that is deeply embedded and superiorly recessed above the renal veins in the retroperitoneum. Occasionally, small perforations of the artery from penetrating wounds can be repaired by lateral arteriorrhaphy or resection with an end-to-end anastomosis. Alternatively, borrowed or substitute arteries, such as the splenic artery to replace the left renal artery and the hepatic artery to replace the right renal artery, have been used rarely, but are not often indicated in hypotensive trauma patients with significant renovascular injuries from penetrating wounds. The survival rate of patients with injuries to the renal arteries from penetrating trauma in two older studies was approximately 87%, with renal salvage in only 30­40%. Intimal tears in the renal arteries may result from deceleration in motor vehicle crashes, automobile-pedestrian accidents, and falls from heights. These usually lead to secondary thrombosis of the vessel and complaints of upper abdominal and flank pain as previously noted. One older literature review noted that only 30% of patients with intimal tears in the renal arteries had gross hematuria, 43% had microscopic hematuria, and 27% had no blood in the urine. The time interval from the episode of trauma appears to be the most critical factor in saving the affected kidney. Of interest, only three of seven patients not undergoing revascularization required late nephrectomy. Either digital compression or the direct application of a Santinsky or Henly vascular clamp can be used to control bleeding from a perforation of the renal vein. If ligation of the right renal vein is necessary to control hemorrhage, nephrectomy should be performed either at the initial operation or at the reoperation if damage control has been necessary. The medial left renal vein, however, can be ligated as long as the left adrenal and gonadal veins are intact. Alternate approaches are nephrectomy versus perfusion of the removed kidney with Euro-Collins solution and autotransplantation. Documentation of a successful result is usually not possible until the acute kidney injury resolves over several weeks. It is of interest that some case reports in the literature have documented either spontaneous recovery or the late successful revascularization of one or both kidneys after presumed blunt thrombosis of the renal artery. Therefore, patients with injuries to only one renal artery should be considered for revascularization only if they are stable and have short warm ischemia times, ideally less than 5 hours. Other patients, assuming they have a normally functioning contralateral kidney, should be either observed or considered for endovascular procedures. Obviously, patients with bilateral renal artery injuries or those with injuries to a solitary kidney should be strongly considered for revascularization. In addition, prolonged follow-up should be arranged for all patients, as some will develop hypertension. The majority of injuries reported in major series are the result of penetrating trauma. It is of interest, however, that major blunt abdominal trauma or pelvic fractures, particularly of the open type, have, in the past 25 years, become a more frequent cause of occlusion or laceration of the iliac arteries than previously noted. The proximal common iliac arteries are exposed by eviscerating the small bowel to the right and dividing the midline retroperitoneum over the aortic bifurcation. In young trauma patients, there is usually no adherence between the common iliac artery and vein in this location, and vessel loops or vascular tapes can be passed rapidly around the proximal arteries. Distal vascular control is obtained at the point at which the external iliac artery comes out of the pelvis proximal to the inguinal ligament. The artery is readily palpable under the retroperitoneum and can be rapidly elevated Chapter 34 Abdominal Vascular Injury 667 into the field of view with vessel loops or a vascular tapes. The major problem in this area is continued back-bleeding from the internal iliac artery. This artery can be exposed by further opening the retroperitoneum on the side of the pelvis, elevating the vessel loops or vascular tapes on the proximal common iliac and distal external iliac arteries, and looking for the large branch of the iliac artery that descends into the pelvis. When bilateral iliac vascular injuries are present, one of the former coauthors of this chapter (Jon M. This includes proximal cross-clamping of the abdominal aorta and inferior vena cava just above their bifurcations and distal cross-clamping of both the external iliac artery and vein with one clamp on each side of the pelvis. Injuries to the iliac veins are exposed through a technique similar to that described for injuries to the iliac arteries. It is not usually necessary to pass vessel loops or vascular tapes around these vessels, however, because they are readily compressible with either sponge-sticks or fingers. As previously noted, the somewhat inaccessible location of the right common iliac vein has led to the suggested temporary transection of the right common iliac artery in order to improve exposure at this location. Ligation of either vessel in the hypotensive patient will lead to progressive ischemia of the lower extremity and the need for a high above-knee amputation or a hip disarticulation in the later postoperative course. Furthermore, in a large review by Burch et al in the 1980s, mortality associated with ligation was 90%. Both end-to-end repairs and vascular grafts in this location have suffered postoperative pseudoaneurysm formation and even blowouts secondary to pelvic infection from the original intestinal contamination. Rather, the artery is divided just proximal to the injury, closed with a doublerunning row of 4-0 or 5-0 polypropylene sutures, and covered with noninjured retroperitoneum or a vascularized pedicle of omentum. The survival rate among patients with injuries to the iliac arteries will vary with the number of associated injuries to the iliac vein, aorta, and vena cava, but was approximately 61% in 189 patients reviewed in four large series published from 1981 to 1990 (Table 34-7). In this series, the authors reported a 95% incidence of penetrating injuries with a mean estimated blood loss of 6246 + 6174 mL. Of the 185 injured vessels, 71 (99%) of 72 iliac arteries were repaired, 101 (89%) of the 113 iliac veins were ligated and overall survival was 51% (76/148). Survival by vessel included the following: iliac artery, 57% (20/35); iliac vein, 55% (42/76); and iliac artery and vein combined, 38% (14/37). Significant predictors of outcome were thoracotomy in the emergency department, associated injury to the abdominal aorta or inferior vena cava, combined injuries to the iliac artery and vein, intraoperative arrhythmia, and intraoperative coagulopathy. On logistic regression, independent risk factors for survival were absence of thoracotomy in the emergency department, surgical management, and arrhythmias. The survival rates in two recent series for patients with injuries to the common iliac artery (other vascular injuries not specified) ranged from 44. Also, it was noted that, even in busy trauma centers, significant delays to operative intervention occur, most notably prolonged emergency department time and anesthesia preparation times, and these delays adversely affected patient outcome. Blunt trauma to the iliac arteries is still less common as they are protected by the bony pelvis and lie deep in the retroperitoneum. Partial transections, avulsions, and intimal injuries with secondary thrombosis have all been reported in association with pelvic fractures, particularly in recent years as previously noted. Of the 10 patients with blunt thromboses reported in the literature until 1997, most had been treated with prosthetic interposition grafting, although several underwent primary repairs. As noted above, the recent study of patients in the National Trauma Data Bank documented a 7. The survival rate of patients with injuries to the iliac veins is variable, but was approximately 70% in 404 patients reviewed in five large series published from 1981 to 1990 (see Table 34-7). Furthermore, this vascular injury may be in combination with an injury to the common bile duct. When a hematoma is present, the proximal hepatoduodenal ligament should be looped with vessel loops or vascular tape or a noncrushing vascular clamp should be applied (the Pringle maneuver) before the hematoma is entered. If hemorrhage is occurring, finger compression of the bleeding vessels will suffice until the vascular clamp is in place. The Pringle maneuver clamps the distal common bile duct as well as the bleeding vessels, but led to only one stricture of the common bile duct in one older series of hepatic injuries from the Ben Taub General Hospital in Houston, Texas. In such patients, manual compression with forceps may allow distal vascular control until the area of injury can be isolated. Because of the proximity of the common bile duct, no sutures should be placed into the porta until the vascular injury is precisely defined. Injuries to the portal vein in the hepatoduodenal ligament are isolated in much the same fashion as injuries to the hepatic artery. The posterior position of the vein, however, makes the exposure of these injuries more difficult. Mobilization of the common bile duct to the left and of the cystic duct superiorly, coupled with an extensive Kocher maneuver, will usually allow for excellent visualization of any suprapancreatic injury after proximal (and, if possible, distal) vascular control has been obtained. As with proximal wounds to the superior mesenteric artery or vein, division of the neck of the pancreas is necessary on rare occasions to visualize perforations in the Common, External, and Internal Iliac Veins Injuries to the common or external iliac vein are treated either with lateral repair using 4-0 or 5-0 polypropylene Chapter 34 Abdominal Vascular Injury 669 retropancreatic portion of the portal vein. With the assistant compressing the superior mesenteric vein below and a vascular clamp applied to the hepatoduodenal ligament above, the surgeon should open both ends of the retropancreatic tunnel over the anterior wall of the portal vein by gently spreading a clamp or scissors. This maneuver may be prevented above by the position of the gastroduodenal artery, which should then be divided and ligated. The pancreas is divided between the clamps and retracted away until the perforations in the portal vein or proximal superior mesenteric or splenic veins are visualized. Hepatic Artery Due to its short course, injury to any portion of the hepatic artery is rare. Replacement of the injured common hepatic artery with a substitute vascular conduit is rarely indicated, since most patients with a portal hematoma or hemorrhage have significant injuries to the liver, right kidney, or inferior vena cava, also. As previously noted, ligation of the proper or common hepatic artery appears to be well tolerated in the young trauma patient, even when performed beyond the origin of the gastroduodenal artery, owing to the extensive collateral arterial flow to the liver. Because of its rarity, few large studies have been performed on injuries to the hepatic artery. A relatively large multicenter experience was published in 1995 by Jurkovich et al which documented the course of 99 patients with injury to the portal triad. Only one patient developed hepatic necrosis requiring debridement, and this patient had an associated extensive injury to that lobe. Seven patients had attempts at repair with only one survivor, and two other patients exsanguinated prior to therapy. Portal Vein As noted above, injuries to any portion of the portal vein are more difficult to manage than are injuries to the hepatic artery, owing to the posterior location of the vein, the friability of its wall, and the greater blood flow through it. Techniques for repair of the vein are varied, but lateral venorrhaphy with a 4-0 or 5-0 polypropylene suture is preferred. More extensive maneuvers that have occasionally been used with success include the following: resection with an end-to-end anastomosis, interposition grafting, transposition of the splenic vein down to the superior mesenteric vein to replace the proximal portal vein, an end-to-side portacaval shunt, and a venovenous shunt from the superior mesenteric vein to the distal portal vein or inferior vena cava. Unfortunately, any type of portal­systemic shunt may have the undesirable effect of causing hepatic encephalopathy, since the direction of splanchnic venous flow with the shunt would mimic that in the patient with cirrhosis and hepatofugal flow in the obstructed portal vein. Ligation of the vein is compatible with survival, as both Pachter et al,164 Stone et al,107 and Asensio8 have emphasized. In the 1979 review of the literature on this subject by Pachter et al, one of six survivors of ligation of the portal vein developed portal hypertension. The surgeon must then be prepared to infuse significant amounts of fluids to reverse the transient peripheral hypovolemia secondary to splanchnic hypervolemia. The comprehensive older review by Graham et al of 37 patients with injuries to the portal vein reported that 26 underwent lateral venorrhaphy, 5 had packing or clamping only, 4 (none of whom survived) had ligation, 1 had an end-to-end anastomosis, and 1 had a portacaval shunt. This led to an overall survival rate of 36% compared with the 50% survival rate among 134 patients with injuries to the portal vein in six series from 1978 to 1987 (see Table 34-7). Zone 1 Patients with injury to the intra-abdominal aorta, especially after penetrating trauma, usually present with hemorrhagic shock from free intraperitoneal hemorrhage. Alternatively, they may present acutely or in a delayed fashion with thrombotic sequelae. First described by Campbell and Austin in 1969,168 "seat belt aorta" describes acute aortic occlusion related to lap-belt injuries. In the past, operative intervention has generally been the only option for definitive management; however, several endovascular techniques have recently been reported to address thrombotic complications of aortic injury in both the acute and chronic settings.

Genital Injuries While penile fractures and testicular ruptures are best managed with early recognition as well as operative exploration and repair birth control for women 60th order online mircette, certain genital injuries due to blunt trauma may be managed nonoperatively birth control for teens generic mircette 15 mcg without a prescription. For penile injuries birth control 3 months order generic mircette on-line, nonoperative management is appropriate for rupture of subcutaneous vessels resulting in limited ecchymosis or a hematoma birth control pills quarterly generic mircette 15 mcg visa. Scrotal trauma may be managed nonoperatively when the testis is intact and there is a limited hematocele that is not bothersome to the patient birth control 3 month pack cheap mircette 15 mcg buy on line. In most situations, however, significant genital trauma is best managed by operative exploration and repair. If physical findings are suspicious of a significant injury to deep tissue or the injury cannot be ruled out by imaging studies, operative exploration is prudent. This is because the outcomes of nonoperative management of such injuries like penile fracture or testicular rupture are poor as compared with the very high success rates of early operative repair. An intratesticular hematoma without testicular rupture is generally managed nonoperatively. At times, testicular ultrasound may demonstrate an abnormality in which a preexisting testicular lesion such as a germ cell neoplasm is suspected. Such may be the case when relatively minor trauma causes a significant intratesticular bleed or testicular rupture. When preexisting testicular pathology is suspected and nonoperative management is selected for the traumatic lesion, it is critical that the testis be reevaluated until the suspicious abnormality resolves or its continuing presence mandates further imaging and intervention. For genital injuries involving significant loss of soft tissue or skin, nonoperative management may be appropriate as an initial approach, especially when more immediately life-threatening injuries demand priority. Wounds should be cleansed and a conservative approach should be adopted when determining whether to perform debridement of genital skin or soft tissues of marginal or questionable viability. Secondary operative management and delayed reconstruction with skin grafting or other tissue transfer techniques is often necessary when wounds are initially managed in this manner. When contemplating exploration of an injured kidney in the absence of preoperative imaging, some assessment of the presence and normalcy of the contralateral kidney should be undertaken. Palpating the contralateral renal fossa for a grossly normal kidney is certainly appropriate and is often the only assessment necessary. This can be performed by administering 1­2 mL/kg of iodinated contrast intravenously and then obtaining a 10-minute excretion film. This can occur while other general surgical tasks are being accomplished to avoid wasting time. There has been some controversy regarding the importance of first obtaining vascular control of the renal pedicle prior to renal exploration, as previously described. Others claim that this maneuver is unnecessary for successful renal exploration and repair. This controversy is probably overstated, as even those who do not believe that individual dissection of the renal vessels is essential prior to renal mobilization tend to use some other approach to control the pedicle or limit renal bleeding during examination and repair of the kidney. The bulk of the literature would suggest that the rate of otherwise unnecessary nephrectomies is minimized by having exposure and control of the renal pedicle prior to renal exploration. Alternatively, the pedicle or the renal parenchyma can be compressed digitally (most applicable to polar injuries) without having individual control over the renal vessels. Certainly, if there is an injury to the pedicle suggested by a large or expanding medial hematoma in the vicinity of the great vessels, there is broad agreement that central vascular control should be the initial maneuver. Following pedicle control or access, the colon and mesocolon on the side of the injury are dissected medially following incision of the peritoneal reflection. As indicated earlier in the section "Anatomy," it is important to dissect in an extracapsular plane and avoid inadvertently dissecting the renal capsule away from the underlying cortex. Accomplishing this is facilitated by beginning the dissection in an area of intact parenchyma rather than directly within the laceration. Completely mobilizing the kidney is very helpful, as it allows the kidney to be lifted anteriorly into the wound for complete inspection. If significant bleeding results during this maneuver, a noncrushing vascular clamp is applied to the renal artery, renal vein, or entire renal pedicle. An initial decision must be made regarding renal salvageability and the magnitude of the reconstructive effort that would be required to repair the injury. This is based largely on the amount of devitalized parenchyma, the degree of injury to the central vasculature and central collecting system, and the condition of the patient. If the kidney is determined to be reconstructible in an unstable patient, any significant intrarenal vascular injury can be rapidly sutured and the kidney can be packed off with laparotomy pads as other surgical injuries are treated (see Chapter 41). After repair of other injuries, or at the time of a secondary surgical procedure, a formal exploration and reconstruction of the kidney is performed. If, based on the anatomy of the injury, the kidney is not considered reconstructible, a nephrectomy is performed. It is preferable to separately ligate the renal artery and vein to avoid the potential for arteriovenous fistula. A rapid search is made for accessory or polar vessels which must be ligated as well. While urologists frequently suture or simply ligate the renal artery and a long stump of vein, vascular surgeons and some urologists prefer to oversew the short right renal vein with a continuous 3-0 or 4-0 Prolene suture. Some clinicians believe preliminary control of the renal vessels is not necessary when performing renal exploration for trauma, although best renal salvage rates are reported when vascular access or control is obtained. Blunt dissection lateral to vena cava allows creation of space anterior to psoas muscle for placement of pedicle clamp if necessary on renal exposure. Large areas of lacerated, devitalized parenchyma are excised sharply, while smaller vessels are controlled with an absorbable 3-0 or 4-0 suture. In general, an absorbable suture is utilized for intrarenal suturing, as a permanent suture may create a nidus for stone formation if in contact with the collecting system. If adequate closure of the collecting system is achieved, there is no need for stenting or a nephrostomy. Chapter 36 Genitourinary Trauma 713 incomplete, placement of an internal stent (complemented by a bladder catheter) or a nephrostomy tube may decrease the risk of postoperative urinary extravasation and the formation of an urinoma. Topical hemostatic agents may be placed within a parenchymal defect to aid in hemostasis, with the capsule closed over the defect and the hemostatic material. If the capsule can be closed with mattress sutures or absorbable bolsters following debridement or partial nephrectomy, parenchymal hemostasis is aided considerably. If capsular closure is not feasible, either due to the shape and location of the parenchymal defect or due to loss of the capsule from the injury or dissection, utilizing absorbable materials or native tissue as a patch may be helpful if hemostasis is still problematic. The argon beam coagulator has also been utilized successfully in the kidney to achieve hemostasis in the parenchyma after suturing larger vessels and closing the collecting system. Topical hemostatic agents and tissue adhesives may be used on the kidney, collecting system, ureter, and other urologic repairs to aid in hemostasis and minimize the risk of postoperative urinary extravasation. Injuries to adjacent organs such as the liver, pancreas, duodenum, and colon generally do not change the indications for renal salvage versus nephrectomy,71,72 as good results have been described for renal repairs in the presence of injuries to these adjacent organs. It is desirable, however, to separate the renal injury from the adjacent visceral injury using available viable tissue. Drains for renal injury are utilized when the injury is complex, incompletely repaired injuries to the collecting system are present, or there is concern for the need to evacuate blood postoperatively. Closed-suction drains are used because there is a lower risk of contributing to postoperative infection. When an injury to an adjacent organ exists, the organ sites should be drained separately. Certain injuries are more common in the pediatric population and deserve specific mention. Avulsions of the fornices, ureteropelvic junction, and renal pedicle are more commonly seen in the pediatric population than in the adult. Avulsions of the ureteropelvic junction are amenable to repair through a direct anastomosis. Lacerations of the renal pelvis should also alert the trauma surgeon to the possibility of a preexisting obstruction of the ureteropelvic junction. Repair of the obstructing lesion may need to be performed with closure of the pelvis, or nephrectomy may be preferable if the kidney appears to have minimal parenchyma due to long-standing obstruction. Renovascular injury from blunt or penetrating trauma presents certain challenges (see Chapter 37). Capsule has been reflected back for completion of partial nephrectomy and will be used for coverage of defect. It is desirable to separate such injuries with viable tissue interposition, when possible, to minimize the risk of postoperative leak from either source affecting the other repair. The artery is clamped near the aorta and opened at the circular ring of hematoma, resected to the point of normal anatomy, and a direct endto-end anastomosis is performed. As in the pediatric population (in which the injury is more common), avulsion injuries involving the renovascular pedicle require urgent surgical intervention. Most of these patients are managed with nephrectomy although isolated vascular repairs have been described depending on the level of the avulsion. Avulsion of multiple branches from within the renal sinus is virtually impossible to repair in the trauma setting and generally requires nephrectomy as well. While current data suggest that the likelihood of achieving a favorable outcome with renal revascularization following renal injury is low,74 patient selection is critical. In the appropriate clinical setting (brief warm ischemia time and a patient in suitable condition for surgery), the effort may be worthwhile in carefully selected patients. In selected cases in which an intimal disruption of the renal artery is documented arteriographically but perfusion is maintained, radiologic placement of a vascular stent may be applicable. Many limited penetrating injuries to the renal vein can be repaired while arterial injuries have a high rate of nephrectomy. When diagnosed on imaging studies in stable patients with intact parenchyma, nonoperative management is appropriate. One kidney can also be packed off temporarily after obtaining gross hemostasis while the opposite kidney is assessed in an effort to avoid nephrectomy in these cases whenever possible. Although rarely indicated, ex vivo renal reconstructive surgery may be utilized in the trauma setting. This would be the case when a solitary (functionally or anatomically) kidney is injured and a complex reconstruction is needed for salvage. Ureter the approach to ureteral repair depends largely on the level of the injury, the amount of ureteral loss (if any), and the condition of the local tissues. A ureteral laceration along with extensive destruction of the kidney from blunt or penetrating trauma is generally managed with nephrectomy. If the kidney is uninjured or the renal injury is limited and can be observed or repaired, ureteral repair is best performed at the time of recognition. Blunt avulsion of the proximal ureter or ureteropelvic junction is best managed with limited debridement to viable tissue and a spatulated end-to-end anastomosis using fine absorbable suture (3-0, 4-0, or 5-0). This can be performed with an internal double-J-type stent or an externalized single-J stent. The single-J stent is usually exteriorized through a small stab incision in the anterior bladder wall and secured with a purse-string suture. Some surgeons also secure the stent to the bladder mucosa just outside the ureteral orifice with a fine absorbable suture (4-0 or 5-0). For tenuous repairs of the proximal ureter, diversion using a nephrostomy tube may be considered but is generally unnecessary. A blunt injury to the midureter is uncommon, but when diagnosed, it is managed with a primary anastomosis. In the distal ureter (below the internal iliac artery), ureteral reimplantation into the bladder is preferred. Injuries to the ureter from penetrating trauma also require a high index of suspicion for diagnosis. The presence of urine in the operative field may be difficult to appreciate, and the ureters, when at risk, must be thoroughly assessed by intraoperative inspection. The proximal and midureters down to the internal iliac arteries are easy to visualize and examine. For very distal injuries, a vertical cystotomy with observation of efflux from the ureteral orifices and intraoperative retrograde pyelography may be a less morbid means of assessing the area of concern rather than embarking on a difficult dissection of the ureter all the way to the bladder in the setting of a pelvic hematoma. Alternatively, intraoperative flexible cystoscopy with retrograde pyelography may be performed, avoiding the cystotomy. For very distal injuries (generally below the internal iliac artery), reimplantation into the bladder is preferred as noted earlier because the blood supply to the distal ureteral stump may be compromised. A direct anastomosis to the bladder avoids the potential ischemic complications of a very distal ureter-to-ureter anastomosis. For injuries to the lower third of the ureter, it is not always possible to perform a direct anastomosis to the bladder without tension. In such cases, the bladder can be brought cephalad and lateral toward the injured side to achieve a tension-free anastomosis with the ureter by several techniques. The bladder is opened anteriorly, lateral peritoneal attachments are divided as needed, and then the bladder body is displaced toward the side of the injury and sutured to the psoas muscle with 2-0 absorbable suture, taking care not to injure or entrap any major nerves. A tunneled, antirefluxing anastomosis of the ureter to the posterior wall of the bladder is performed, being certain that an adequatewidth tunnel is created to prevent obstruction. If the available ureteral length is short, antirefluxing tunneling can be eliminated. Either an internal double-J-type stent or an externalized single-J stent can be used (not shown). The bladder body can be seen sutured to the left psoas muscle, with the ureter entering cephalad. A single-J ureteral stent and suprapubic cystostomy exit from the bladder in the lower part of the photograph. It is important to ensure that no obstruction or acute angulation exists at the vesical hiatus where the ureter enters. If a psoas hitch cannot achieve a tension-free connection to the ureter, a bladder flap (Boari flap) can be created.

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