Stanley Z. Trooskin

Lactate clearance and survival following injury.

Previous reports cite optimization of O2 delivery (DO2) to 660 mL/min/m2, O2 consumption (VO2) to 170 mL/min/m2, and cardiac index (CI) of 4.5 L/min as predicting survival. We prospectively evaluated 76 consecutive patients with multiple trauma admitted directly to the ICU from the operating room or emergency department. Patients had serum lactate levels and oxygen transport measured on ICU admission and at 8, 16, 24, 36, and 48 hours. Patients were analyzed with respect to survival (S) versus nonsurvival (NS), lactate clearance to normal (< or = 2 mmol/L) by 24 and 48 hours, hemodynamic optimization as defined above, as well as Injury Severity Score (ISS), ICU stay (LOS), and admission blood pressure. All patients achieved non-flow-dependent VO2. There was no difference in CI, DO2, VO2, or ISS when S was compared with NS. All 27 patients whose lactate level normalized in 24 hours survived. If lactate levels cleared to normal between 24 and 48 hours, the survival rate was 75%. Only 3 of the 22 patients who did not clear their lactate level to normal by 48 hours survived. Ten of the 25 nonsurvivors (40%) achieved the above arbitrary optimization criteria. Fifteen of the survivors never achieved any of these criteria. Optimization alone does not predict survival. However, the time needed to normalize serum lactate levels is an important prognostic factor for survival in severely injured patients.

Hemodynamic responses to shock in young trauma patients: Need for invasive monitoring

Objective: To determine whether early invasive monitoring is necessary in young trauma patients. Design: A prospective study. Setting: Surgical intensive care unit (ICU) at an inner-city, Level I trauma center. Patients: Thirty-nine patients 6 units of intraoperative blood. Interventions: Invasive hemodynamic monitoring, with percutaneous insertion of arterial and pulmonary artery catheters. Vital signs, hemodynamic and oxygen transport values, and laboratory tests were obtained at 1, 8, and 24 hrs postoperatively. Oxygen delivery was increased until a normal serum lactate concentration and a state of nonflow-dependent oxygen consumption were achieved

Resuscitation of multiple trauma and head injury: Role of crystalloid fluids and inotropes

Objectives: To determine the hemodynamic responses to blunt trauma with a closed‐head injury and to investigate the effect that volume resuscitation has on intracranial pressure. Design: Prospective study with retrospective analysis of patient data and hemodynamic responses. Setting: Surgical intensive care unit at an inner‐city, Level I trauma center. Patients: Consecutive patients (n = 30) who sustained multiple system injury, including a closed‐head injury that was severe enough to require intracranial pressure monitoring but not a craniotomy. Interventions: All patients underwent invasive hemodynamic monitoring with percutaneous arterial and pulmonary arterial catheters. Serum lactate concentrations and hemodynamic and oxygen transport variables were measured every 4 hrs. Intracranial pressures and vital signs were recorded each hour. Attempts were made to achieve a state of nonflow‐dependent oxygen consumption and a normal serum lactate concentration. Measurements and Main Results: Despite being normotensive and neither tachycardiac nor oliguric, 80% of patients had evidence of inadequate tissue perfusion. Only 50% of the remaining patients had an adequate response to volume. The other 50% received vasodilating inotropic agents. Despite volume loading and the administration of inotropic agents, intracranial pressure did not increase. This observation was found in patients who showed clinically important intracranial pathology on computed tomography scan, as well as in all other patients. Intracranial pressure did not correlate with the amount of fluid or blood infused or with hemodynamic performance, but intracranial pressures did correlate with serum lactate concentrations. Conclusions: Many patients with diffuse blunt trauma closed‐head injuries, even when they are normotensive, have evidence of impaired peripheral perfusion. Volume infusion and vasodilating inotropic support improve oxygen transport without increasing intracranial pressure. The observed relationship between intracranial pressure and the serum lactate concentration requires further study. (Crit Care Med 1994; 22:1610–1615)

Video assessment of trauma response: Adherence to ATLS protocols

A novel strategy using videotape recordings of initial trauma resuscitations was incorporated into the quality assurance program at a level 1 trauma center. Described are the process of taping the resuscitations, the multidisciplinary nature of the resuscitation team, the security measures taken to assure patient confidentiality, and the review process involved. The videotape review process was incorporated into a multidisciplinary educational trauma conference. The videotapes were used to evaluate the adherence to Advanced Trauma Life Support (ATLS) resuscitation protocols. Resident performance in six aspects of the ATLS resuscitation process were specifically highlighted on each videotape and graded for adherence to preestablished standards. The videotape process allowed an unblased, indisputable accurate documentation of the sequential application of the protocols of evaluation and resuscitation espoused in the ATLS course. We found 23% overall deviation from ATLS resuscitation principles, with at least one aspect of the resuscitation deviating from expected ATLS performance in 64% of the patients. In addition to documenting adherence to ATLS principles, this study illustrated the impact of the videotape review process on the education of eight senior residents in surgery.

THE MANAGEMENT OF GUNSHOT WOUNDS TO THE FACE

Treatment principles for penetrating neck trauma are well described yet few exist for facial injuries. To help delineate these issues, we viewed our recent experience with gunshot wounds to the face. Since 1986 we have treated 100 patients with such injuries. Their mean age was 28.9 years (range, 12-77 years). There were 89 male patients and 11 female patients. Ninety-six patients were considered stable on initial examination. Yet 35 patients required urgent airway control in the ED; only two needed a surgical airway. Emergency angiography was performed in 37 patients; 19 vascular injuries were identified. Eleven required therapy for vascular injuries, five by neck exploration and six by embolization. In 15 patients the trajectory suggested an intracranial injury, i.e., across the base of the skull. Although 14 of 16 patients were awake and alert at examination, head CT scans demonstrated serious intracranial pathologic processes in 9 patients. Sixty-seven patients sustained bony injury, 19 patients a significant nonvascular soft-tissue injury, and 38 patients a significant neurologic injury (26 peripheral, one spinal and 20 cerebral injuries). Ultimately, 44% of all patients required some surgical treatment and 25% had a complication from their injury. Six patients died, three of CNS injury, one of exsanguination, and two of sepsis. The bony, soft tissue, nervous, and vascular anatomy make the management of gunshot wounds to the face challenging. Although initially stable, many patients require early airway control and urgent work-up for vascular and intracranial injuries. Early subspecialty input is helpful in delineating the often complex injury pattern and planning an optimal management strategy.

Diagnostic performance of trauma US in identifying abdominal or pelvic free fluid and serious abdominal or pelvic injury

RATIONALE AND OBJECTIVES This study assessed the ability of a six-point trauma ultrasound (US) evaluation (a) to identify the presence of free fluid in the abdomen or pelvis, with computed tomography (CT) and laparotomy used as diagnostic standards and (b) to predict the presence of abdominal or pelvic injury, particularly injury requiring surgical intervention. MATERIALS AND METHODS Of 156 patients who underwent US evaluation for free fluid after sustaining blunt and penetrating trauma, 147 were entered into the prospective study and underwent follow-up CT and/or laparotomy (n = 79), in-hospital observation, or outpatient examination. RESULTS The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of US for identifying abdominal or pelvic free fluid were 69%, 100%, 100%, 95%, and 95%, respectively. The corresponding values for predicting abdominal and pelvic injury on the basis of free fluid status alone were 57%, 99%, 80%, 96%, and 95%, respectively. Performing repeated US examinations in patients with deteriorating clinical status decreased the false-negative rate by 50%, increasing the sensitivity for free fluid detection to 85% and the negative predictive value to 97%. Similarly, the sensitivity and negative predictive value for detection of injury increased to 71% and 97%, respectively. A learning curve was also observed, with 67% of the false-negative findings occurring in the first 3 months of the 19-month study. CONCLUSION A six-point trauma US evaluation can reliably identify abdominal and pelvic free fluid, which can be a reliable indicator of abdominal or pelvic injury. Scanning conditions must be optimized, and the approach to clinical management must be cautious.

Antioxidant enzymes are induced during recovery from acute lung injury.

Objective To determine the contribution of the pulmonary antioxidant defense enzymes of the hexose monophosphate (HMP) shunt and glutathione systems to recovery from oxidant-mediated lung injury in an animal model shown to closely resemble the clinical syndrome of acute respiratory distress syndrome. Design Prospective, controlled laboratory study on phorbol myristate acetate (PMA)-induced lung injury in rabbits. Setting Animal research laboratory. Subjects Rabbits were injected with PMA (80 &mgr;g/kg) for 3 consecutive days. Control animals received normal saline. Measurements and Main Results Lungs were harvested at 24, 48, 72, and 96 hrs (n = 5/time point) after PMA injection or after the third injection of normal saline in control animals (n = 6). The cytosolic fraction from lung and bronchial alveolar lavage (BAL) fluid was used for measurements of HMP shunt and glutathione enzymes. Pulmonary activity peaked at 48 hrs post-PMA injury with a 40% increase in glucose-6-phosphate dehydrogenase activity and a 32% increase in 6-phosphogluconate dehydrogenase activity over control levels. BAL activity was maximal at 72 hrs with an increase of 98% in glucose-6-phosphate dehydrogenase and 346% in 6-phosphogluconate dehydrogenase activities. Glutathione peroxidase was maximally induced by 77% at 48 hrs in BAL and by 107% at 24 hrs in lung. Glutathione reductase activity did not increase significantly in either lung or BAL. Conclusions The observed induction of the antioxidant enzymes in response to PMA suggests that both the HMP shunt and the glutathione systems contribute to the recovery phase of oxidant-mediated lung injury. The inability of natural host defenses to regenerate reduced glutathione may explain failure of recovery from acute respiratory distress syndrome and suggests an avenue for clinical intervention.

Nonoperative management of blunt abdominal trauma: The role of sequential diagnostic peritoneal lavage, computed tomography, and angiography

STUDY OBJECTIVE To determine the usefulness of sequential nonoperative diagnostic studies in the evaluation and treatment of stable patients after blunt abdominal trauma. DESIGN AND SETTING Retrospective review of a prospective treatment plan in a large urban Level I trauma center. PARTICIPANTS Fifty-two patients deemed stable after initial evaluation following blunt abdominal trauma. INTERVENTIONS Patients with a positive diagnostic peritoneal lavage for red blood cells underwent abdominal computed tomography (CT) scanning. If CT demonstrated a visceral injury, it was followed by diagnostic angiography. Attempts were made to treat on-going bleeding by transcatheter embolization. RESULTS Fifteen patients had negative CT scans and were successfully observed. In the other 37 patients, CT identified 17 liver, 16 splenic, and eight kidney injuries; eight extra-peritoneal bleeds; and one mesenteric hematoma. Six of these patients were observed. Thirty underwent diagnostic angiograms. Twelve had no active bleeding, and all were observed successfully. Seventeen underwent successful embolization of the bleeding site(s). One had injuries not controllable by embolization and required exploration. Six patients required laparotomy later in their course, but none had intra-abdominal bleeding or a missed intestinal injury. Despite being performed after diagnostic peritoneal lavage, CT missed only two injuries. There was one main complication, delayed recognition of a diaphragmatic injury. Three patients died, two from multiple organ failure and one from a pulmonary embolus; none was believed to be related to this technique. With our algorithm, 45 patients (86%) were spared laparotomy. CONCLUSION Diagnostic peritoneal lavage and CT are complementary when evaluating blunt abdominal trauma. Diagnostic peritoneal lavage is an effective screening tool. CT may be reserved for stable patients with a positive diagnostic peritoneal lavage to specify the organs injured. Bleeding often may be treated by embolization, limiting the rate of surgery.

Hemodynamic responses to penetrating spinal cord injuries

Although the hemodynamic response to blunt spinal cord injury has been well described, much less is known about the responses to penetrating spinal cord injuries. In order to elucidate any differences, we reviewed the last 75 patients treated over the past 12 years with penetrating spinal cord injuries. There were 67 men and eight women; the mean age was 26.2 years (range, 15-59 years); 73 patients suffered 120 gunshot wounds; one patient was injured with an ice pick; one was stabbed twice. The offending missile causing spinal cord injury entered the neck in 24%, the thorax in 56%, and the abdomen in 20%. Nine patients (12%) were complete quadriplegics and 49 patients (65%) were complete paraplegics; 69 patients (92%) had no rectal tone; 17 patients (22%) had incomplete injuries. Despite the high proportion of complete spinal injury (78%), only 18 patients (24%) were hypotensive in the field. Five additional patients became hypotensive in the ED. Of the 23 patients with hypotension, 18 (74%) had significant blood loss to explain their low blood pressure. The mean HR was 100 beats/minute in the field (range, 50-130 beats/minute) and 90 beats/minute in the ED. Only five patients (7%) demonstrated the classic presentation of neurogenic shock (hypotension and bradycardia). This classic presentation of neurogenic shock is rare following penetrating spinal cord injury. Despite evidence of a complete spinal cord injury on initial physical examination, hypotension is usually secondary to blood loss in these patients. A careful search for sources of blood loss is mandatory before ascribing hypotension to spinal injury.

Improved emergency department efficiency with a three-tier trauma triage system

This pilot study was carried out to determine whether converting from a two-tier to a three-tier in-hospital trauma triage system improves the efficiency of emergency department (ED) care and minimizes inappropriate triage. Patients at an urban, Level 1 trauma centre were triaged using either a two-tier (months 1-3; n = 197) or three-tier (months 4-6; n = 240) trauma response system. Patients were assessed for triage type, age, sex, injury severity score, Glasgow coma score, post-ED disposition, total ED time, survival, complication rate, probability of survival and unexpected death. Comparisons were made by ANOVA table analysis; significance was assumed for p < 0.05. Two-tier (n = 197) and three-tier patients (n = 240) were matched with respect to mean age, sex, mean injury severity score, mean Glasgow coma score, post-ED disposition, survival and probability of survival. Two-tier patients were triaged to give 20% alerts [criteria = physiological derangement (PD) and/or injury mechanism (MOI)] and 80% consults; three-tier patients were triaged as 20% category I (criteria = PD), 18% category II (criteria = MOI) and 62% consults. Total ED time decreased from two-tier (3.98 +/- 2.81 h) to three-tier triage (3.53 +/- 2.14 h, p = 0.001). There was no difference between two-tier alert and three-tier category I times (2.09 +/- 1.64 vs. 1.95 +/- 1.75 h; p = 0.72). Category II patients (3.28 +/- 1.98 h; p = 0.009) spent less time in the ED than did two-tier consults (4.36 +/- 2.65 h). The mean ED three-tier consult time significantly decreased as well (3.95 +/- 2.42 h, p = 0.008 vs. two-tier consult). Complications per patient were unchanged from two-tier to three-tier triage (0.17 +/- 0.52 vs. 0.12 +/- 0.48; p = 0.15). Under-triage (5%) and over-triage (7.5%) were minimal under three-tier triage. It is concluded that using a three-tier triage system results in an increase in the early involvement of the trauma service while decreasing emergency department time and minimizing over-triage.