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BACKGROUND: Published contraindications to nonoperative management (NOM) of blunt splenic injury (BSI) include age > or = 55, Glasgow Coma Scale score < or = 13, admission blood pressure < 100 mm Hg, major (grades 3-5) injuries, and large amounts of hemoperitoneum. Recently reported NOM rates approximate 60%, with failure rates of 10% to 15%. This study evaluated our failures of NOM for BSI relative to these clinical factors. METHODS: All patients with BSI at a Level I trauma center over a 46-month period ending September 1999 were reviewed. Failures of NOM included patients initially selected for NOM who subsequently required splenectomy/splenorrhaphy. RESULTS: Five hundred fifty-eight had BSI. Twenty-three percent (128) underwent emergent laparotomy for hemodynamic instability and 77% (430) were observed. The NOM failure rate was only 8%. Univariate analysis identified moderate to large hemoperitoneum (p < 0.03), grades 3 to 5 (p < 0.004), and age > or = 55 (p < 0.0006) as being significantly associated with failure. Multivariate analysis identified age > or = 55 and grades 3 to 5 injuries as independent predictors of failure. The highest failure rates (30-40%) occurred in patients age > or = 55 with major injury for moderate to large hemoperitoneum. Mortality rates for successful NOM were 12%, and 9% for failed NOM. CONCLUSION: Inclusion of all high-risk patients increased the NOM rate while maintaining a low failure rate. Although age > or = 55 and major BSI were independently associated with failure of NOM, approximately 80% of these high-risk patients were successfully managed nonoperatively. There was no increased mortality associated with failure. Although these factors may indeed predict failure, they do not necessarily contraindicate NOM.
We demonstrated that the standard clinical criteria of fever, leukocytosis, purulent sputum, and infiltrate on chest radiograph are nonspecific for the diagnosis of post-traumatic pneumonia, and only approximately 50 per cent of patients with these conditions have pneumonia. Quantitative cultures of bronchoalveolar lavage effluent will differentiate pneumonia (requiring antibiotic therapy) from systemic inflammatory response syndrome (not requiring antibiotics). Early identification of patients at risk for pneumonia can target populations for clinical research. Because risk factors for pneumonia when diagnosed by quantitative cultures have not been defined we reviewed our recent experience to identify variables predictive of pneumonia. Patients over a 22-month period who survived > 48 hours were identified from the trauma registry. Pneumonia was defined as growth of > or = 10(5) organisms per milliliter in the bronchoalveolar lavage effluent. Risk factors evaluated included injury severity and severity of shock. There were 7503 patients (75% with blunt and 25% with penetrating injuries). The incidence of pneumonia was 6 per cent (7% of patients with blunt and 2% of patients with penetrating injuries). Logistic regression analysis identified age; Glasgow Coma Scale score; Injury Severity Score; transfusion requirements during resuscitation; spinal cord injury; chest injury severity; and emergent femur fixation, craniotomy, and laparotomy as being independent predictors of pneumonia. We conclude that multiple risk factors, which are all able to be determined early after injury, are predictive of post-traumatic pneumonia. Prompt identification of this high-risk group of patients allows prognostic considerations relative to patient management schemes and targets populations for prophylactic measures or immunomodulation.
BACKGROUND: The adequacy of intermittent and continuous infusion ceftazidime for the treatment of nosocomial pneumonia in critically ill trauma patients was assessed by analyzing ceftazidime pharmacokinetics in relation to the minimum inhibitory concentration (MIC) and treatment outcome. METHODS: Serial blood samples were obtained during ceftazidime therapy in 31 trauma patients. Ceftazidime pharmacokinetics were compared with that of previously studied healthy volunteers. Ceftazidime pharmacokinetics were analyzed according to the time above the MIC and treatment outcome. RESULTS: Critically ill trauma patients had a significantly increased volume of distribution and clearance (0.32 +/- 0.14 L/kg and 2.35 +/- 0.89 mL. min(-1). kg(-1), respectively) compared with healthy volunteers (0.21 +/- 0.03 and 1.58 +/- 0.23 mL. min(-1). kg(-1)). The time above the MIC was >/=92% of the dosing interval for all patients and treatment outcomes were similar between the two treatment groups. CONCLUSIONS: Ceftazidime pharmacokinetics are significantly altered in critically ill trauma patients. Both intermittent and continuous ceftazidime regimens were equally effective for the treatment of nosocomial pneumonia caused by less virulent bacteria.
BACKGROUND: Gastric outlet obstruction (GOO) secondary to peptic ulcer disease requiring therapeutic intervention remains a common problem. The incidence of Helicobacter pylori infection in this cohort has not been well defined. Pneumatic dilatation (PD) has been proposed as first-line therapy before surgical intervention. If H pylori infection in patients with GOO is infrequent, PD may not offer permanent control without the need for longterm antacid therapy. STUDY DESIGN: The purpose of this study was to examine the incidence of H pylori infection and surgical outcomes in patients undergoing resection for GOO. The records of all patients having resection (vagotomy and antrectomy) for benign disease from 1993 to 1998 for GOO at the University of Tennessee affiliated hospitals were reviewed retrospectively. Smoking history, NSAID use, weight loss, previous ulcer treatment, previous treatment for H pylori, and previous attempts at PD were among the factors examined. H pylori infection was documented by Steiner stain from either preoperative biopsy or, in most patients, final surgical specimens. Surgical complications and patient satisfaction were ascertained from inpatient records, postoperative clinical notes, and, where possible, followup telephone surveys. RESULTS: Twenty-four patients underwent surgical resection during the study period. There were 16 men and 8 women, with a mean age of 61 years (range 40 to 87 years). Weight loss was documented in 58% and averaged 27 lb. Five of 24 patients had previous attempts at PD, 3 of whom were H pylori negative. All five had further weight loss after these failed attempts. Of the 24 patients reviewed, only 8 (33%) were H pylori positive. There were no procedure-related deaths. Longterm clinical followup was possible in 16 of 24 patients, and all but one demonstrated dramatic clinical improvement by Visick score. CONCLUSIONS: We conclude the following: 1) In this cohort, H pylori infection was present in a minority; 2) previous attempts at PD were unsuccessful, which may be related to the H pylori-negative status of the patients; 3) mortality related to the operation was zero; and 4) patient satisfaction was positive by the Visick scale. Patients with H pylori-negative GOO resulting from peptic ulcer disease should be strongly considered for an early, definitive, acid-reducing surgical procedure.
OBJECTIVE: To analyze the outcome of hemodynamically stable patients with blunt hepatic injury managed nonoperatively, and to examine the impact of this approach on the outcome of all patients with blunt hepatic injury. SUMMARY BACKGROUND DATA: Until recently, operative management has been the standard for liver injury. A prospective trial from the authors' institution had shown that nonoperative management could safely be applied to hemodynamically stable patients with blunt hepatic injury. The present study reviewed the authors' institutional experience with blunt hepatic trauma since that trial and compared the results with prior institutional experience. METHODS: Six hundred sixty-one patients with blunt hepatic trauma during the 5-year period ending December 1998 were reviewed (NONOP2). The outcomes were compared with two previous studies from this institution: operative 1985 to 1990 (OP) and nonoperative 1993 to 1994 (NONOP1). RESULTS: All 168 OP patients were managed operatively. Twenty-four (18%) of 136 NONOP1 patients and 101 (15%) of the 661 NONOP2 patients required immediate exploration for hemodynamic instability. Forty-two (7%) patients failed nonoperative management; 20 were liver-related. Liver-related failures of nonoperative management were associated with higher-grade injuries and with larger amounts of hemoperitoneum on computed tomography scanning. Twenty-four-hour transfusions, abdominal infections, and hospital length of stay were all significantly lower in the NONOP1 and NONOP2 groups versus the OP cohort. The liver-related death rate was constant at 4% in the three cohorts over the three time periods. CONCLUSIONS: Although urgent surgery continues to be the standard for hemodynamically compromised patients with blunt hepatic trauma, there has been a paradigm shift in the management of hemodynamically stable patients. Approximately 85% of all patients with blunt hepatic trauma are stable. In this group, nonoperative management significantly improves outcomes over operative management in terms of decreased abdominal infections, decreased transfusions, and decreased lengths of hospital stay.
OBJECTIVE: To determine the negative predictive value of cranial computed tomography (CT) scanning in a prospective series of patients and whether hospital admission for observation is mandatory after a negative diagnostic evaluation after minimal head injury (MHI). SUMMARY BACKGROUND DATA: Hospital admission for observation is a current standard of practice for patients who have sustained MHI, despite having undergone diagnostic studies that exclude the presence of an intracranial injury. The reasons for this practice are multifactorial and include the perceived false-negative rate of all standard diagnostic tests, the belief that admission will allow prompt diagnosis of occult injuries, and medicolegal considerations about the risk of early discharge. METHODS: In a prospective, multiinstitutional study during a 22-month period at four level I trauma centers, all patients with MHI were evaluated using the following protocol: a standardized physical and neurologic examination in the emergency department, cranial CT scanning, and then admission for observation. MHI was defined as either a documented loss of consciousness or evidence of posttraumatic amnesia and an emergency department Glasgow Coma Scale score of 14 or 15. Outcomes were measured at 20 hours and at discharge and included clinical deterioration, need for craniotomy, and death. RESULTS: Two thousand one hundred fifty-two consecutive patients fulfilled the study protocol. The CT was interpreted as negative for intracranial injury in 1,788, positive in 217, and equivocal in 119. Five patients with CT scans initially interpreted as negative required intervention. There was one craniotomy in a patient whose CT scan was initially interpreted as negative. This patient had facial fractures that required surgical intervention and elevation of depressed intracranial fracture fragments. The negative predictive power of a cranial CT scan based on the preliminary reading of the CT scan and defined by the subsequent need for neurosurgical intervention in the population fully satisfying the protocol was 99.70%. CONCLUSIONS: Patients with a cranial CT scan, obtained on a helical CT scanner, that shows no intracerebral injury and who do not have other body system injuries or a persistence of any neurologic finding can be safely discharged from the emergency department without a period of either inpatient or outpatient observation. Implementation of this practice could result in a potential decrease of more than 500,000 hospital admissions annually.
BACKGROUND: Fiberoptic bronchoscopy (FB) plays an important role in making the diagnosis of nosocomial pneumonia and resolving lobar atelectasis in critically injured trauma patients. It has been shown to be a safe procedure with only occasional complications. However, in patients with head injuries, FB can lead to intracranial hypertension. Sustained increases in intracranial pressure (ICP) leads to poor outcome in these patients. Because of this, a prospective study was done not only to assess the effect of FB on ICP and cerebral perfusion pressure (CPP) in patients with brain injuries, but also to identify a regimen of sedation and anesthesia that could prevent significant increases in ICP during FB. METHODS: Twenty-six FB were performed in 23 patients with ICP monitors or ICP monitors and ventriculostomy drains in place for Glasgow Coma Scale score < 8 or management of postcraniotomy trauma. FB was performed to aid in the diagnosis of nosocomial pneumonia or to aid in resolving lobar atelectasis. Before FB, all patients received a standard anesthetic regimen consisting of vecuronium (10 mg), morphine sulfate (4 mg), and midazolam (2.5 mg). Patients with diminished cranial compliance, defined as ICP > 10 mm Hg, also received a nebulizer treatment of 3 mL of 4% lidocaine before FB. All patients were preoxygenated with FIO2 = 1.0 for 10 minutes. Intracranial pressure, mean arterial pressure, and CPP were monitored continuously throughout the procedure. These same variables were also recorded at baseline and at 2-minute intervals during the procedure. The time to return to baseline ICP was also recorded. RESULTS: The mean ICP at baseline (immediately before FB) was 12.6 mm Hg. After introduction of the bronchoscope, the ICP rapidly increased in 21 procedures (81%) and the mean highest ICP was 38.0 mm Hg. There was also a concomitant increase in mean arterial pressure such that there was no substantial change in CPP. The mean lowest CPP was 73.1 mm Hg. The average time for return of ICP to baseline was 13.9 minutes. In the subgroup of patients with ICP > 10, attempting to blunt the tracheal stimulation by anesthetizing the trachea with 4% nebulized lidocaine did not seem to be successful. The mean highest ICP in this subgroup was 41.8 mm Hg. The CPP changed in a similar manner, as the mean lowest CPP was 74.0 mm Hg. The mean time to return to baseline was 12.5 minutes. No patient had acute neurologic deterioration secondary to FB. CONCLUSIONS: Although FB is an important procedure in the pulmonary care of head injured patients, it produces substantial, but transient, increases in ICP and should be used with caution in patients with diminished cranial compliance. Sedation, analgesia, paralysis, and topical tracheal anesthesia did not completely prevent the rise in ICP. Although no acute deterioration in condition occurred, secondary brain injury caused by localized cerebral ischemia is certainly possible. Because of the substantial increases in ICP, herniation may be precipitated in an occasional patient. Further study is needed to identify a regimen that will confer protection.
BACKGROUND: Early generation scanners have demonstrated poor sensitivity detecting blunt bowel/mesenteric injuries (BBMI). This study was aimed at determining the accuracy and role of helical scanners in BBMI. METHODS: Retrospective chart review of patients with BBMI, or computed tomographic scans suspicious of BBMI, from August of 1995 to December of 1998. RESULTS: One hundred of 8,112 scans (1.2%) were suspicious of BBMI. Of these suspicious scans, 53 patients had BBMI (true positive-TP) and 47 patients did not (false positive-FP). Seven patients with negative scans had BBMI (false negative-FN). Computed tomography contributed toward early surgery in 77% of patients who may have been delayed. Six patients developed intra-abdominal abscess. The abscess group had a significantly longer time interval from injury to surgery. Multiple findings were seen in 57% of true positive scans, whereas in 13% of false positive scans (p < 0.0001). An algorithm for management of BBMI is presented. CONCLUSION: Helical scanners have high accuracy in detecting BBMI. Single versus multiple findings are useful in managing these injuries.
BACKGROUND: The purpose of this study was to test whether polynitroxylation (PN) improved the therapeutic profile of hemoglobin-based oxygen-carrying compounds (HBOCs) that were unpolymerized (alphaalphaHb) or 70% polymerized (polyHb) in a clinically relevant model that combines pulmonary injury and reperfusion. To our knowledge, four different HBOC formulations have never been compared in the same trauma model. METHODS: Anesthetized, ventilated swine (n = 45) received a unilateral lung contusion + 25% hemorrhage. After 60 minutes, 250 mL of either PNalphaalphaHb (n = 5), alphaalphaHb (n = 10), PNpolyHb (n = 6), polyHb (n = 5), or normal saline (NaCl, n = 10) was administered for 20 minutes, followed by standard crystalloid resuscitation for 30 minutes, and supplemental crystalloid as required for 6 hours to maintain heart rate <100 beats/min and mean arterial pressure >70 mm Hg. RESULTS: Nine of 45 deaths occurred before resuscitation. Survival time was 395 minutes with NaCl versus 303 minutes with alphaalphaHb (p = 0.03) or 238 minutes with PNalphaalphaHb (p = 0.04). With both polymerized HBOCs, survival was 480 minutes (polyHb vs. alphaalphaHb, p = 0.005; PNpolyHb vs. PNalphaalphaHb, p = 0.006). All HBOCs were pressors (all p < 0.05) and all reduced the supplemental fluid required to maintain systemic hemodynamics during resuscitation (all p < 0.05). By 90 minutes postresuscitation, cardiac index was 112% of baseline with NaCl (p < 0.02), but was 78% with alphaalphaHb (p = not significant), 63% with PNalphaalphaHb (p < 0.01), 79% with PNpolyHb (p < 0.01), and 67% with polyHb p < 0.02). Relative to NaCI, no HBOC altered trauma-induced neutrophilia, thrombocytopenia, or the trauma-induced increases in bronchoalveolar lavage protein or bronchoalveolar lavage neutrophils. CONCLUSION: After resuscitation from chest trauma, we observed the following: (1) all HBOCs reduced fluid requirements and increased right and left ventricular afterload versus NaCl, which further compromised an already marginal cardiac performance; (2) mortality was less with polyHbs relative to alphaalphaHb, but the pressor action was unchanged; (3) the pressor action was less with polynitroxylated compounds relative to the unmodified HBOC, but this chemical modification had no effect on mortality; and (4) the pressor action of HBOCs must be attenuated by strategies other than polymerization or polynitroxylation for these compounds to be safe, effective resuscitants in humans.
BACKGROUND: No previous studies have examined actions of adenosine or related compounds after blunt chest trauma, but we have shown that the prototype adenosine-regulating agent, acadesine (aminoimidazole carboxamide ribonucleotide [AICAR]), has multiple favorable anti-inflammatory actions after other forms of trauma, ischemia, hemorrhage, and sepsis; and that a progressive inflammatory response in the contralateral (uninjured) lung after unilateral blunt chest trauma is caused (in part) by activation and sequestration of circulating leukocytes (white blood cells [WBCs]). Thus, we hypothesized that AICAR would ameliorate WBC-dependent, secondary pathophysiologic changes after blunt chest trauma. METHODS: Mongrel pigs (28+/-1 kg, n = 21) were anesthetized, mechanically ventilated, and injured on the right chest (pulmonary contusion) with a captive bolt gun. Either AICAR (1 mg/kg + 0.2 mg/kg/min) or its saline vehicle were administered for a 12-hour period, beginning 15 minutes before injury. RESULTS: Injury caused a three- to fourfold increase in bronchoalveolar lavage (BAL) WBC counts, 10- to 20-fold increases in BAL protein, and 200% increases in lung edema as measured by wet-dry ratio (all p < 0.05), in both the injured (right) and the noninjured (left) lungs. With AICAR versus saline, BAL WBC counts, lung myeloperoxidase levels, and systemic hemodynamics were similar. However, the increases in BAL protein were attenuated by 30% to 50% (p < 0.14, NS) and edema was reduced (p < 0.05) in both lungs. Furthermore, oxygenation, hypercapnia, acidosis (all p < 0.05), and survival were improved (9 of 10 vs. 4 of 11, p < 0.04). CONCLUSION: Pretreatment with AICAR before experimental pulmonary contusion ameliorates the trauma-induced destruction of the alveolar capillary membrane, and attenuates the delayed secondary injury in the contralateral uninjured lung, by a mechanism that may be independent of leukocytes. Endogenous adenosine could have a role in the pathophysiologic response after blunt chest injury, with potential sites of action including the endothelium and alveolar macrophage. Adenosine-regulating agents may have therapeutic potential after blunt chest injury, but further studies are needed in clinically relevant models, with administration begun at the time of resuscitation.
Previous work suggests that neutrophils (PMNs) and/or prostaglandins might mediate the progressive respiratory failure after severe pulmonary contusion. Since reactive oxygen metabolites are closely associated with both these factors, we examined the actions of a novel antioxidant after swine received a unilateral injury followed by 25% hemorrhage. An infusion (2mL/kg/h intravenously x 6 h) of either polynitroxylated 5% Dextran + Tempol (PND, n = 9), 5% Dextran (D, n = 6), or lactated Ringers (LR, n = 13) was begun 60 min post-injury to mimic 'pre-hospital resuscitation.' After 15 min, standard resuscitation was initiated (3x shed blood as LR in 30 min) plus further LR for 6 h to maintain hemodynamics. The total LR requirement was lower with PND (1,772+/-267 mL) versus D (3,040+/-689, P = 0.0563) or LR (4145+/-398, P = 0.0005). The ipsilateral bronchoalveolar lavage (BAL) PMN count with PND (8+/-2 x 10(5)/mL), was not different from its baseline (P = 0.131), but the counts with D (16+/-3) and LR (17+/-4) were both higher than their baselines (P = 0.0184 and 0.0431). Similarly, BAL protein with PND (1,560+/-350 mg %) was not elevated from its baseline (P = 0.0721), but the values with D (2,560+/-498) and LR (2,474+/-899) were both higher than their baselines (P = 0.0169 and 0.0325). In the contralateral (uninjured) lung, the effects were similar, but the increases were less for PMNs (8+/-2 versus 10+/-2 or 14+/-4 x 10(5)/mL) and for protein (609 +/-153 versus 1,955+/-671 or 1486+/-357 mg %). Despite these significant BAL changes, there was no obvious improvement in cardiopulmonary dysfunction. Thus oxidants probably have some role in the pathogenic mechanism of progressive secondary injury after thoracic trauma, but further work is needed to determine the therapeutic potential of antioxidants because no clinical improvement was detected.
OBJECTIVE: A computer-based system to apply trauma resuscitation protocols to patients with penetrating thoracoabdominal trauma was previously validated for 97 consecutive patients at a Level 1 trauma center by a panel of the trauma attendings and further refined by a panel of national trauma experts. The purpose of this article is to describe how this system is now used to objectively critique the actual care given to those patients for process errors in reasoning, independent of outcome. METHODS: A chronological narrative of the care of each patient was presented to the computer program. The actual care was compared with the validated computer protocols at each decision point and differences were classified by a predetermined scoring system from 0 to 100, based on the potential impact on outcome, as critical/noncritical/no errors of commission, omission, or procedure selection. RESULTS: Errors in reasoning occurred in 100% of the 97 cases studied, averaging 11.9/case. Errors of omission were more prevalent than errors of commission (2. 4 errors/case vs 1.2) and were of greater severity (19.4/error vs 5. 1). The largest number of errors involved the failure to record, and perhaps observe, beside information relevant to the reasoning process, an average of 7.4 missing items/patient. Only 2 of the 10 adverse outcomes were judged to be potentially related to errors of reasoning. CONCLUSIONS: Process errors in reasoning were ubiquitous, occurring in every case, although they were infrequently judged to be potentially related to an adverse outcome. Errors of omission were assessed to be more severe. The most common error was failure to consider, or document, available relevant information in the selection of appropriate care.
Nosocomial pneumonia is a frequent complication in hospitalized patients. Gram-positive pathogens, particularly Staphylococcus aureus, are responsible for the increasing frequency of nosocomial pneumonia. To evaluate the efficacy and safety of intravenous quinupristin/dalfopristin (Synercid) in the treatment of nosocomial pneumonia caused by gram-positive pathogens we conducted a prospective, randomized, open-label, international, multicenter, comparative clinical trial. Two hundred ninety-eight patients with nosocomial pneumonia were enrolled in 74 active centers in five countries: a subgroup of 171 (87 quinupristin/dalfopristin-treated and 84 vancomycin-treated patients) were evaluable for the major efficacy end points. One hundred fifty received 7.5 mg/kg of quinupristin/dalfopristin every 8 h; 148 patients received 1 g of vancomycin every 12 h. Aztreonam at a dose of 2 g every 8 h could be administered in both groups for coverage of gram-negative organisms, and tobramycin was added for coverage against Pseudomonas aeruginosa. The primary efficacy end point was the clinical response between the seventh and the thirteenth day after the end of treatment in clinically evaluable patients with documented causative pathogen(s) at baseline (bacteriologically evaluable population). Therapy was clinically successful (cure or improvement) in 49 (56.3%) of patients receiving quinupristin/dalfopristin and 49 (58.3%) patients receiving vancomycin (difference, -2.0% [95% CI, -16.8% to 12.8%]) in the bacteriologically evaluable population. Equivalent clinical success rates were also observed in the all-treated population (n = 298), and in the bacteriologically evaluable patients intubated in baseline (39/72 [54%] compared with 36/67 [54%]). The by-pathogen bacteriologic response was similar in both treatment groups, with equivalent clinical success rates for Streptococcus pneumoniae, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus. Adverse events (venous and nonvenous) were equally distributed between groups; 15.3% of quinupristin/dalfopristin patients and 9.5% of vancomycin patients discontinued therapy because of an adverse clinical event. In this study quinupristin/dalfopristin was shown to be equivalent to vancomycin in the treatment of nosocomial pneumonia caused by gram-positive pathogens. Quinupristin/dalfopristin merits further evaluation for the treatment of nosocomial pneumonia caused by methicillin-resistant S. aureus.
STUDY OBJECTIVE: To determine the effect of oxandrolone administration on nutritional and clinical outcomes after multiple trauma. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: Level 1 trauma center in a university teaching hospital. PATIENTS: Sixty-two patients requiring enteral nutrition, 60 of whom completed the study. INTERVENTION: Patients were randomized to receive either oxandrolone 10 mg or placebo twice/day for a maximum of 28 days. MEASUREMENTS AND MAIN RESULTS: Total urinary nitrogen, prealbumin, nitrogen balance, total body water, and body cell mass were measured on day 1 of enteral nutrition and then at day 7, day 10, and study exit. Patients were assessed daily for metabolic and infectious complications. The two groups were similar for demographics and dosage of enteral nutrition. Measurement of total urinary nitrogen at study entry showed both groups to be highly catabolic (oxandrolone 17.2 +/- 4.9, placebo 19.1 +/- 10.8 g/day, NS). On days 7 and 10, total urinary nitrogen increased in both groups; however, there was no significant difference between groups. Nitrogen balance was negative throughout the study in each group. Body cell mass decreased slightly in both groups over the study period. Prealbumin serum concentrations increased significantly in both groups at day 10 and study exit compared with study entry. The groups did not differ significantly for length of hospital stay (oxandrolone 30.8 +/- 17.9, placebo 27.0 +/- 25.7 days), length of intensive care unit stay (oxandrolone 17.1 +/- 7.8, placebo 15.5 +/- 9.7 days), and frequency of pneumonia or sepsis (oxandrolone 48, placebo 43 episodes). CONCLUSION: Oxandrolone 20 mg/day does not have obvious benefit in nutritional and clinical outcomes during the first month after multiple trauma.
Empiri c therapy of ventilator-associated pneumonia (VAP) in surgical patients should be based on intensive care unit (ICU)-specific surveillance data, because microbial flora patterns vary widely between geographic regions as well as within hospitals. Surgical ICUs have higher VAP rates than other units. Data from the National Nosocomial Infection Surveillance (NNIS) System report Pseudomonas aeruginosa and Staphylococcus aureus to be the most frequent isolates (each 17.4%). Data from the NNIS documents high resistance patterns in ICUs compared with hospitals at large, as well as unit-specific patterns. VAP risk factors for surgical patients include thoracoabdominal surgery, altered level of consciousness, advanced age, diabetes mellitus, malnutrition, chronic obstructive pulmonary disease, and prior antibiotic administration. Promising prevention strategies include restricting ventilator circuit changes, in-line heat moisture exchange filters, semi-recumbant positioning, and continuous subglottic aspiration. Pharmacodynamics should be considered when choosing antibiotic regimens. Postantibiotic effect and time-dependent versus concentration-dependent killing should be studied in clinical trials. Current guidelines for choosing regimens have been well developed by the American Thoracic Society.
Two hypotheses were investigated: (1) helical computed tomography (CT) of the chest on victims of decelerating trauma can yield a diagnosis of, or "rule out," a traumatic rupture of the aorta (TRA) without the need for an aortogram; and (2) selective delay of aortic repair can be safely accomplished through a medical management protocol. Screening helical CT examinations were done on 6169 victims of blunt thoracic trauma; 47 were found to have TRA; in 8, indirect but nondiagnostic findings not clarified by an aortogram led to surgical exploration. The sensitivity of helical CT was higher than that of aortograms, and a "normal" helical CT scan was never associated with a proved TRA. It is estimated that the use of helical CT has resulted in at least a 40% to 50% decrease in the need for aortograms, in addition to yielding rapid, noninvasive valuable information about other injuries. Drugs (beta-blockers +/- vasodilators) to decrease the stress in the aortic wall were used in 93 patients when the diagnosis was suspected and were continued as necessary through the evaluation, stabilization, and until the aorta was cross-clamped at operation. Elective, delayed operation was done between 2 days and 25 months in 15 patients who were deemed to be excessive risks for emergency aortic repair; there were 2 deaths (13. 3%). Eleven patients never had aortic repair. No patient maintained on this protocol, whether repaired emergently, electively, or not at all, developed free rupture of the periaortic hematoma and death from TRA.
OBJECTIVE: To determine whether blood lactate, base deficit, or oxygen-derived hemodynamic variables correlate with morbidity and mortality rates in a clinically-relevant LD50 model of penetrating trauma. DESIGN: Prospective, controlled study. SETTING: University research laboratory. SUBJECTS: Anesthetized, mechanically-ventilated mongrel pigs (30+/-2 kg, n = 29). INTERVENTIONS: A captive bolt gun delivered a penetrating injury to the thigh, followed immediately by a 40% to 60% hemorrhage. After 1 hr, shed blood and supplemental crystalloid were administered for resuscitation. MEASUREMENTS AND MAIN RESULTS: After penetrating injury, 50.7+/-0.3% hemorrhage (range 50% to 52.5%), and a 1-hr shock period, seven of 14 animals died, compared with six of six animals after 55% to 60% hemorrhage, and 0 of nine animals after < or =47.5% hemorrhage. Only two of 13 deaths occurred during fluid resuscitation. At the LD50 hemorrhage, peak lactate concentration and base deficit were 11.2+/-0.8 mM and 9.3+/-1.5 mmol/L, respectively, and minimum mixed venous oxygen saturation, systemic oxygen delivery, and systemic oxygen consumption were 33+/-5%, 380+/-83 mL/min/kg, and 177+/-35 mL/min/kg, respectively. For comparison, baseline preinjury values were 1.6+/-0.1 mM, -6.7+/-0.6 mmol/L, 71+/-3%, 2189+/-198 mL/min/kg, and 628+/-102 mL/min/kg, respectively. Of all the variables, only lactate was significantly related to blood loss before and after fluid resuscitation in the 16 survivors. However, r2 values were relatively low (.20 to .50), which indicates that only a small fraction of the hyperiactacidemia was directly related to tissue hypoperfusion. In the whole population of survivors and nonsurvivors, both lactate and base deficit (but none of the oxygen-derived variables) correlated with blood loss. CONCLUSIONS: Arterial lactate is a stronger index of blood loss after penetrating trauma than base deficit or oxygen-derived hemodynamic variables. The reliability of arterial lactate depends on several factors, such as the time after injury, the proportion of survivors and nonsurvivors in the study population, and on factors other than tissue hypoxia.