Adrenal insufficiency in hemorrhagic shock.

Adrenal insufficiency during sepsis is well documented. The association between hemorrhagic shock and adrenal insufficiency is unclear and may be related to ischemia, necrosis, or resuscitation. This study was designed to determine the incidence of relative adrenal insufficiency in hemorrhagic shock. A retrospective review of a prospectively gathered database for patients admitted to the trauma intensive care unit with hemorrhagic shock was undertaken. A random serum cortisol of <25 mcg/dL defined relative adrenal insufficiency. All of the cortisol levels were drawn within the first 24 hours of admission. Data analyzed included demographics, length of stay, injury mechanism, infections, and mortality. Fifteen patients presented with hemorrhagic shock, with 14 of 15 meeting the criteria for relative adrenal insufficiency. The average serum cortisol level was 15.8 (9-26.8). The average APACHE II score was 18.3 (4-33), and the average Injury Severity Score was 22.5 (8-41). The mechanism was blunt trauma in 10 patients and penetrating trauma in 5. The average intensive care unit and hospital length of stay were 13.2 and 27.4 days, respectively. There were five urinary tract infections, four blood stream infections, and two wound infections. Two of the 15 patients died. Relative adrenal insufficiency appears to be common in hemorrhagic shock. Future research is warranted to elucidate the pathophysiology, as well as to prospectively determine which patients may benefit from steroid replacement.

Adrenal insufficiency in the critically III trauma population.

Acute adrenal insufficiency has been demonstrated in a number of patients with shock. This study was designed to evaluate the rate of occult adrenal insufficiency in the critically ill trauma population and to determine the impact of hypoproteinemia on the use of random cortisol levels as a marker for adrenal insufficiency. Forty-four patients were prospectively enrolled on admission to the trauma intensive care unit, with three excluded, for a total n of 41. Random total serum cortisol and albumin levels were drawn on hospital Days 1, 4, 8, and 14. Occult adrenal insufficiency was defined as a cortisol less than 25 mcg/dL in the setting of an albumin greater than 2.5 g/dL. The prevalence of cortisol less than 25 mcg/dL ranged from 51 to 81 per cent during the study period, and peaked on Days 4 and 8. Albumin 2.5 g/dL or less ranged from 37 to 60 per cent, and this prevalence also peaked on Days 4 and 8. The patients with a low albumin had a high prevalence of low cortisol, ranging from 67 to 100 per cent. The prevalence of adrenal insufficiency, with low cortisol and normal albumin, ranged from 41 to 82 per cent during the study period. None of our patients with occult adrenal insufficiency were treated with steroids, which was a decision made by the treating physicians. Among the patients with occult adrenal insufficiency, survival was 100 per cent. Occult adrenal insufficiency is common in critically ill trauma patients, and is a dynamic entity that can be acquired and even resolved during critical illness. Random cortisol of 25 mcg/dL may actually not be an adequate marker of occult adrenal insufficiency. Low albumin predicts a low cortisol. Hemodynamically stable occult adrenal insufficiency should not be treated with steroid replacement in the critically ill trauma patient, as survival in our series was 100 per cent without replacement.

Secondary abdominal compartment syndrome: risk factors and outcomes.

Secondary abdominal compartment syndrome (ACS), defined as intra-abdominal hypertension with associated pulmonary, renal, or hemodynamic compromise in the absence of preceding abdominal operation or injury, can markedly increase surgical morbidity and mortality. We performed a retrospective chart review of the physiologic parameters and outcomes of 10 patients with secondary ACS. Ten patients developed secondary ACS after aggressive resuscitation, at an average of 20.2 hours. Four of the patients sustained burns greater than 40 per cent, three of the patients had penetrating extremity trauma, one patient had blunt abdominal trauma, one patient was struck by lightning, and one patient developed a retroperitoneal bleed while on heparin. The average bladder pressure was 40.6. The average volume given in the first 24 hours was 33,001 cc (range, 12,400 to 69,000). The average base deficit at admission was -12 (range, +1 to -25). Seven of the 10 patients had decreased urine output. Nine of the 10 patients had decreased tidal volumes on pressure control ventilation. All 10 patients were hypotensive, with 7 of the 10 requiring vasopressors. Overall mortality was 60 per cent, with 43 per cent mortality for those decompressed. Prompt recognition and treatment are mandatory for survival of ACS. We recommend routine bladder pressure monitoring for patients with ongoing resuscitation greater than 500 cc/hr.

The usefulness of serum troponin levels in evaluating cardiac injury.

The diagnosis and clinical significance of blunt cardiac injury remains controversial. Cardiac troponin I is not found in skeletal muscle and has a high sensitivity for myocardial ischemia or injury. We hypothesized that normal troponin levels 4 to 6 hours postinjury would effectively exclude the diagnosis of cardiac contusion. A prospective evaluation of all blunt trauma patients older than 16 and admitted with the possible diagnosis of blunt cardiac injury was undertaken. Patients in whom this diagnosis was considered had an electrocardiogram (EKG) on admission, serum troponin, CPK and isoenzymes 4 to 6 hours postinjury, and admission with overnight telemetry. Other laboratory data and radiographic imaging was obtained as indicated. Seventy-two patients met criteria for entry into the study. Data was incomplete or inaccurately obtained on six patients, and they were excluded. Forty patients had normal troponins and normal EKG's on admission and were discharged the following day without any untoward effect. Sixteen patients were admitted with abnormal EKGs. All of these 16 patients had normal troponins 4 to 6 hours after their injury. They all did well and were discharged the following day. Ten patients had elevated troponins 4 to 6 hours after injury. One died two days later from refractory cardiogenic shock. Another was noted to have severely depressed left ventricular function by echocardiography. The other eight patients sustained no cardiac sequelae and were discharged once recovered from injuries. In the hemodynamically stable patient a normal troponin 4 to 6 hours after injury excludes clinically significant blunt cardiac injury. This holds true whether the admission EKG is normal or not. An elevated troponin does not definitively diagnose a clinically significant contusion. However, these patients should be monitored at least for 24 hours. Patients suspicious for cardiac contusions who have normal troponins and no other serious injuries may be safely discharged to go home from the emergency department.

Blunt trauma and the role of routine pelvic radiographs.

We evaluated clinical factors that are predictive of pelvic X-ray findings. We sought to identify whether routine pelvic films are necessary in blunt trauma and addressed whether removal of these films would minimize cost. We performed a retrospective chart review of 111 patients without pelvic fractures and 108 with pelvic fractures seen at our Level 1 trauma center between August 1998 and September 1999. We evaluated initial hemodynamics, physical examination findings, laboratory data, and hospital charges. Patients with fractures had higher Injury Severity Scores (P < 0.001), a higher number of associated injuries (P < 0.001), and lower blood pressures (P < 0.001). The back and pelvic examinations were significantly associated with X-ray results (P < 0.001), and the potential savings with selective radiography was $168,300.00 per year. We believe that clinical factors identified in our study predict the need for pelvic X-ray. Because removal of these films would minimize cost we recommend the elimination of routine pelvic films for the awake and alert blunt trauma patient.

Newer diagnostic modalities for vascular injuries: the way we were, the way we are.

The article discusses the role of modalities in diagnosing vascular injuries starting with angiography and tracing the evolution of the use of color flow Doppler, CT, and CT angiography. It also addresses the controversy of minimal vascular injury and outlines vascular injuries that may be safely observed and followed-up. Finally, the evolution from angiography to the use of helical CT for the diagnosis of thoracic aortic injuries is reviewed in detail.

"Alternative" surgery in trauma management.

Alternative" surgery in the trauma discipline essentially means nonoperative or a selective approach to the injured victim. Such an approach is a critical part of the trauma management options. However, it is unlikely that the term "alternative surgery" will be liberally used to depict this growing trend of nonoperative, selective, and minimally invasive trauma management because of its less than favorable connotations and biases with respect to alternative medicine. Although there are still clear indications for emergency operative intervention, the nonoperative or selective approach in both penetrating and blunt trauma is the state of the art.

Alternative modalities of ventilation in acute respiratory failure.

Acute respiratory failure continues to complicate the management of critically ill trauma and surgical patients. Despite an increased understanding of the pathophysiology of this process, there is no golden bullet with which to stop or reverse it. Management remains directed toward maintenance of gas exchange and minimizing complications until such time as the process that initiated the respiratory failure has resolved and the lungs have an opportunity to recover. Continuous positive pressure ventilation with PEEP and oxygen is the conventional modality for achieving this goal. It is apparent that some patients are refractory to this therapy. In addition, there is evidence that alveolar injury may occur as a result of increasing airway pressures and shear forces. These authors have reviewed a number of modalities that seek to address these issues. IRV, whether pressure or volume controlled, appears at least able to provide adequate gas exchange in some patients who are refractory to conventional therapies. The same appears to be true for pressure control ventilation, airway pressure release ventilation, and volume control ventilation with a modified decelerating flow waveform. Whether any of these modalities will prove to alter outcome with respect to mortality remains to be seen. Work continues in the arena of extrapulmonary oxygenation. Results of recent studies are improved compared to the results of the NIH trial reflecting advances in technology, technique, and experience. The IVOX is a fascinating device that has been shown to effectively transfer respiratory gases, as has perfluorocarbon associated gas exchange. Whether these technologies will find a role in the treatment of adult respiratory failure awaits further study.

Alkaline phosphatase levels in diagnostic peritoneal lavage fluid as a predictor of hollow visceral injury.

Isolated injuries to hollow viscera may result in equivocal diagnostic peritoneal lavage (DPL) findings. Small bowel injuries cause alkaline phosphatase (AP) levels to increase in DPL effluent. The goal of this study was to better define the role of AP levels in the evaluation of the injured abdomen. We prospectively measured AP levels in 672 patients undergoing DPL. These were retrospectively compared with the clinical findings. All 12 patients with small bowel injuries and three of four with large bowel injuries had an AP level > 10 IU/L. There was one patient with an AP level > 10 IU/L without clinically significant intra-abdominal injury. An AP level > 10 IU/L in the DPL effluent predicted injury requiring laparotomy with a specificity of 99.8% and a sensitivity of 94.7%. We recommend using AP levels only in the management of patients with equivocal findings on DPL who would otherwise not undergo laparotomy. This selective use of AP levels will improve the probability of early diagnosis of bowel injury without increasing the cost of care.

Associated aortic rupture-pelvic fracture: an alert for orthopedic and general surgeons.

Blunt trauma patients with pelvic fractures have been shown to have a two-fold to five-fold increased risk of aortic rupture compared with the overall blunt trauma population. A retrospective review was performed to determine whether the relationship between aortic rupture and pelvic fracture could be further delineated using a pelvic fracture classification based on mechanism of injury. Of 4,157 consecutive blunt trauma patients, 371 (8.9%) had pelvic fractures, 34 (0.8%) had ruptured thoracic aortas and 12 had both injuries. When pelvic fractures were classified according to vector of force, 10 of 12 (83%) aortic ruptures occurred in patients with an anterior-posterior compression fracture pattern, an incidence of aortic rupture eight times greater than that of the overall blunt trauma population. There was no increased incidence of aortic rupture among patients with any other pelvic fracture pattern. We conclude that the previously reported association between aortic rupture and pelvic fracture can be further specified to include, predominantly, those patients with an anterior-posterior compression fracture pattern.