ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundPatients injured in rural counties are hypothesized to have improved survival if local hospitals are categorized as Level III, Level IV, and Level V trauma centers.MethodsData were abstracted on patients with brain, liver, or spleen injuries who were first treated in 16 rural hospitals in Oregon (with categorized trauma centers) and 16 hospitals in Washington (without categorized trauma centers). Logistic regression models evaluated survival up to 30 days after hospital discharge.ResultsAmong Oregon’s 642 study patients, 63% were transferred to another hospital. Among Washington’s 624 patients, a higher proportion, 70%, were transferred. Risk-adjusted odds of death for Washington patients (reference odds, 1) were the same as for Oregon patients (odds ratio, 0.82; 95% confidence interval, 0.53–1.28). Most patients died after transfer to another hospital.ConclusionIn states with a prevailing practice of promptly transferring brain-injured patients, survival of these patients may not be enhanced by categorization of hospitals as rural trauma centers. To further improve the outcome of these patients, policy makers should adjust statewide trauma system guidelines to enhance integration and to perfect coordination among sequential decision makers.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundIn Europe and Switzerland, hardly any studies have been performed on regional trauma systems. We therefore decided to conduct a prospective study in our region to establish whether an organized trauma system derived from the American model would have a beneficial effect on the survival of blunt polytrauma patients.MethodsIn a prospective observational cohort study conducted between 1990 and 1996, we compared the actual mortality in 280 blunt polytrauma patients admitted directly to our trauma center with the predicted mortality using the A Severity Characterization of Trauma score. The same comparison was made for 190 transferred polytrauma admissions from regional hospitals. Our hypothesis was that for the transferred admissions, the actual mortality would be significantly higher than predicted, but that there would be no difference for the directly admitted patients. Inclusion criteria were blunt trauma of at least two body sites and an Injury Severity Score of 8 or more.ResultsMortality in the patients admitted directly to the trauma center was 11.8% (33 of 280), which was not significantly lower than that for the transferred admissions at 14.2% (27 of 190). There were 10% (3 of 30) more deaths than predicted among the direct admissions (i.e., 3 more deaths; 95% confidence interval, −5.2–11.1;p= NS). Among the transferred admissions, there were 46% (8.6 of 18.4) more deaths than predicted (i.e., 8.6 more deaths; 95% confidence interval, 2.5–14.7;p< 0.05).ConclusionIt is likely that a regional trauma system in eastern Switzerland for polytrauma patients with an ISS of 8 or more would have a moderately positive effect on mortality. During the period of observation, transferred admissions from regional hospitals to our trauma center had a 46% higher mortality than predicted. In absolute terms, therefore, with a regional trauma system, it might have been possible to avoid between one death every 2 to 3 years and two to three deaths every year.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

IntroductionWe present a series of adult patients treated under a protocol for severe lung failure (acute respiratory distress syndrome [ARDS]) that uses positive end-expiratory pressure (PEEP) optimization and intermittent prone positioning (IPP) to reduce shunt, improve oxygen (O2) delivery, and reduce Fio2.MethodsTrauma, emergency vascular, and general surgical patients with Pao2/Fio2(PF) ratio < 200 were entered into a protocol designed to maintain mixed venous saturation (Svo2) > 70% with Fio2< 0.50. Therapy involved a sequential algorithmic approach that included pulmonary artery oximetry, “best-PEEP” determination, optimization of cardiac function, limitation of Vo2, transfusion to hematocrit of 35%, frequent bronchoscopy, rational diuresis and, if the Fio2was > 0.50, a trial of IPP with every-6-hour rotations. Unstable spine fractures and pelvic external fixators were the only contraindications to IPP. We collected data prospectively and from the charts and trauma registry.ResultsForty adults were treated by protocol, 29 were injured and 11 had vascular or general surgical primary problems. The patients were 46.3 ± 3.1 years old (the trauma patients were 42.9 ± 3.2, and the vascular/general patients were 62 ± 7.5 years old). Average Injury Severity Score was 25.9 ± 3.7 and the Murray lung injury score was 2.65 ± 0.9. IPP was used in all patients including those with recent tracheostomy, open abdomens, laparotomy, thoracotomy, leg external fixators, central nervous system injury, continuous venovenous hemofiltration and extracorporeal membrane oxygenation cannulae, vasopressor therapy, recent chest wall open reduction and internal fixation, and facial fractures. With the initiation of IPP therapy, the PF ratio increased from 132.1 ± 8.5 to 231.6 ± 14.2 (p< 0.001), the Fio2was decreased from 65.9 ± 4.0% to 47.0 ± 1.1% (p< 0.001), and the Svo2increased from 75.3 ± 1.8% to 78.6 ± 1.6% (p= 0.023). PEEP and static compliance were unchanged.The duration of IPP was 85.6 ± 14.9 hours (median, 55 hours; range, 12 to 490 hours). Within 48 hours, all patients were on Fio2≤ 0.50. Mortality was 20% (14% for trauma) and none died of ARDS. The only complications of IPP were one case of partial-thickness skin loss from a malpositioned nasogastric tube and a case of transient lingual edema.ConclusionIPP was independently responsible for an increase in PF ratio and Svo2. We effectively and safely used IPP in our patients with ARDS, including many with issues generally considered to be contraindications. IPP and best-PEEP therapy enabled us to wean all of our patients’ Fio2to ≤ 0.50 within 48 hours of ARDS onset.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundAfter trauma and hemorrhagic shock (T/HS), mesenteric lymph (ML) activates polymorphonuclear neutrophils (PMNs), injures endothelial cells (ECs), and predisposes to lung injury. The involved mediators, however, are unknown. We studied the ability of aqueous (AQ) and lipid (LIP) extracts of rat T/HS ML to activate PMNs and injure ECs.MethodsML was collected from male rats undergoing trauma (laparotomy) plus hemorrhagic shock (30 mm Hg, 90 minutes) or sham shock. AQ and LIP ML fractions were separated using the Bligh-Dyer technique. Human umbilical vein endothelial cells were incubated 18 hours in 5% LIP or AQ lymph fractions and viability was assessed using the MTT assay. Rat PMNs incubated 5 minutes with 3% LIP or AQ fractions were assessed for respiratory burst (RB) and cytosolic calcium ([Ca2+]i) using dihydrorhodamine 123 and fura-2AM. Human PMN responses to AQ and LIP T/HS lymph were studied similarly.ResultsEC incubated in AQ showed 19 ± 4% viability as compared with 65 ± 11% in LIP (p< 0.001). Whole lymph affected ECs comparably to AQ T/HS lymph. Rat PMN basal [Ca2+]iincreased after exposure to AQ but not LIP T/HS lymph extracts. AQ T/HS lymph primed [Ca2+]iresponses to macrophage inflammatory protein-2 and platelet-activating factor; neither LIP T/HS nor any trauma and sham shock lymph fraction caused PMN priming. Rat PMN RB was elevated after AQ T/HS lymph incubation when compared with buffer (610 ± 122 U/s vs. 225 ± 38 U/s,p= 0.01). Rat PMN incubation in LIP T/HS lymph caused minimal activation (289 ± 28 U/s,p= NS). Conversely, human PMN showed [Ca2+]iand RB priming by rat T/HS LIP and not AQ extracts.ConclusionT/HS mesenteric lymph contains multiple biologically active mediators. Both AQ and LIP extracts of T/HS lymph are toxic to human umbilical vein endothelial cells, with AQ more active than LIP. Only AQ T/HS lymph activates rat PMNs, although LIP rat lymph extract activates human PMNs. These findings demonstrate the complex nature of gut lymph-derived biologic factors as well as species-specific differences on PMN and EC physiology. Therapies directed at any one specific molecule or mediator are therefore unlikely to be successful.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

ObjectiveThe purpose of this study was to examine whether cold fluid infusion could rapidly decrease the core temperature and prolong survival during uncontrolled hemorrhagic shock in pigs.MethodsFourteen pigs under light halothane anesthesia and spontaneous breathing underwent initial blood withdrawal of 25 mL/kg over 15 minutes, followed by uncontrolled hemorrhage (5-mm aortotomy). Immediately after the aortotomy, the pigs were randomized to receive 500 mL lactated Ringer’s solution at either 4°C (group 1, n = 7) or 37°C (group 2, n = 7) over 20 minutes through the internal jugular vein and observed until their death or for a maximum of 240 minutes.ResultsThe pulmonary artery temperature of group 1 decreased to 35.5° ± 0.3°C after the infusion, then remained at 35.5°C during the observation period. Pulmonary artery temperature values of group 2 remained at around 37.5°C throughout the experiment. The mean survival time was 220 ± 45 minutes in group 1 versus 136 ± 64 minutes in group 2 (p< 0.05, life table analysis). The additional intraperitoneal blood loss of group 1 was similar to that of group 2 (9 ± 4 g/kg vs. 10 ± 5 g/kg).ConclusionIn lightly anesthetized pigs during uncontrolled hemorrhagic shock, infusion with 4°C lactated Ringer’s solution (which seems to be feasible in the clinical setting) decreases the core temperature rapidly and prolongs survival.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundIschemia/reperfusion-induced polymorphonuclear neutrophil leukocyte (PMN) adhesion and extravasation are pivotal for the development of postinjury multiple organ failure. We hypothesized that the deleterious microcirculatory consequences of hemorrhagic shock (HS) could be altered by low-molecular-weight heparin (LMWH) therapy. Our aim was to investigate the effects of dalteparin sodium on leukocyte-endothelial cell interactions when LMWH treatment was initiated before HS or during resuscitation.MethodsAnesthetized dogs underwent HS (40 mm Hg mean arterial pressure for 60 minutes) and resuscitation either with shed blood or with lactated Ringer’s (LR) solution. LMWH or conventional heparin sodium pretreatment was administered subcutaneously before hemorrhage; or LMWH was given intravenously during resuscitation. Mesenteric postcapillary venules were observed by intravital video microscopy before and after HS, and 60 minutes, 120 minutes, and 180 minutes after resuscitation, and leukocyte rolling and firm adherence were determined.ResultsHS significantly increased PMN rolling and adhesion in the mesenteric microcirculation. LMWH, but not heparin sodium pretreatment, significantly inhibited both primary and secondary interactions. LMWH treatment was also effective when initiated during resuscitation. LMWH exerted the same inhibitory effect regardless of the type of resuscitation.ConclusionLMWH treatment during resuscitation effectively inhibits PMN rolling and adhesion.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundActivated monocytes are able to express tissue factor (TF), a potent procoagulant. The effect of injury on monocyte TF expression is not known. We have found that patients with head injury (HI) have increased antithrombin activity and decreased platelet function compared with non–head-injured trauma patients. Our objective was to determine whether injury increases TF expression by monocytes and whether this increased TF expression is attenuated in patients with HI.MethodsWe prospectively enrolled 37 trauma patients (meeting the entry criterion of an Injury Severity Score [ISS] ≥ 9) and 11 healthy control subjects. We sampled blood on arrival and then at 24, 48, and 72 hours. We performed flow cytometry with antibody markers for monocytes (CD14), platelets (CD42a), and TF. We compared results of patients with HI (Glasgow Coma Scale score ≤ 9 and Abbreviated Injury Scale Head/Neck score ≥ 3) with patients without HI and with controls.ResultsPatients had a mean ISS of 23.9 ± 2.3 (± SEM), mean age of 45 ± 3 years, and mean length of stay of 17.9 ± 3.2 days. Seventy-six percent were men, and 97% had blunt trauma. The overall mortality rate was 11%. Trauma patients had greater monocyte TF expression than controls for all time periods (p< 0.05). Trauma patients with HI had elevated monocyte TF expression compared with controls for the initial and 24-hour time periods, but they subsequently had more rapid return of monocyte TF expression to baseline (despite a higher ISS) than trauma patients without HI. Trauma patients both with and without HI had increased platelet-monocyte binding at each time versus controls.ConclusionTrauma induces TF expression on monocytes. Patients with HI have attenuation of this expression by 24 hours after injury. The attenuation of TF expression by monocytes in HI parallels the increase in AT and the decrease in platelet function seen after HI. The correlation of TF expression with platelet-monocyte binding suggests that platelet binding may lead to monocyte activation.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundHuman patient simulation (HPS) has been used since 1969 for teaching purposes. Only recently has technology advanced to allow application to the complex field of trauma resuscitation. The purpose of our study was to validate an advanced HPS as an evaluation tool of trauma team resuscitation skills.MethodsThe pilot study evaluated 10 three-person military resuscitation teams from community hospitals that participated in a 28-day rotation at a civilian trauma center. Each team consisted of physicians, nurses, and medics. Using the HPS, teams were evaluated on arrival and again on completion of the rotation. In addition, the 10 trauma teams were compared with 5 expert teams composed of experienced trauma surgeons and nurses. Two standardized trauma scenarios were used, representing a severely injured patient with multiple injuries and with an Injury Severity Score of 41 (probability of survival, 50%). Performance was measured using a unique human performance assessment tool that included five scored and eight timed tasks generally accepted as critical to the initial assessment and treatment of a trauma patient. Scored tasks included airway, breathing, circulation, and disability assessments as well as overall organizational skills and a total score. The nonparametric Wilcoxon test was used to compare the military teams’ scores for scenarios 1 and 2, and the comparison of the military teams’ final scores with the expert teams. A value ofp< 0.05 was considered significant.ResultsThe 10 military teams demonstrated significant improvement in four of the five scored (p≤ 0.05) and six of the eight timed (p≤ 0.05) tasks during the final scenario. This improvement reflects the teams’ cumulative didactic and clinical experience during the 28-day trauma refresher course as well as some degree of simulator familiarization. Improved final scores reflected efficient and coordinated team efforts. The military teams’ initial scores were worse than the expert group in all categories, but their final scores were only lower than the expert groups in 2 of 13 measurements (p≤ 0.05).ConclusionNo studies have validated the use of the HPS as an effective teaching or evaluation tool in the complex field of trauma resuscitation. These pilot data demonstrate the ability to evaluate trauma team performance in a reproducible fashion. In addition, we were able to document a significant improvement in team performance after a 28-day trauma refresher course, with scores approaching those of the expert teams.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundThe core of general surgery supports multiple disciplines, each of which entails similar operative care for different diseases. The purpose of this study was to compare variations of practice patterns of four general surgeons to define the general surgical core that each shared in common, and to determine the effect of subspecialization in surgical critical care on the scope of practice and efficiency of revenue production.MethodsThe charges and collections of four members of the same surgical faculty were analyzed for the 6 months beginning July 1, 2000. Three members practiced general surgery with additional specialization in surgical oncology, surgical endoscopy, and trauma/critical care. The fourth covered all aspects of general surgery, including in-house trauma call, but not surgical critical care. Data were stratified by Current Procedural Terminology code and categorized as operative, bedside care (which included minor procedures), and evaluation/consultation care. Scope of practice was defined as the proportion of operative cases represented by the 10 most frequently performed procedures. General surgical core was defined as those cases that were preformed by all four surgeons at the same frequency. Efficiency of revenue generation was defined as collection rate for these procedures divided by the established, budgeted collection rate for each practitioner. All results were compared using &khgr;2with significance accepted atp< 0.05.ResultsFifteen operative procedures were performed with equal frequency by each surgeon and represented a broad spectrum of surgical disease. These procedures constituted a similar proportion of operative practice for all specialists (mean, 45.2%; 90% confidence limit, 3.5%), yet occupied 70% of the trauma surgeon’s 10 most frequent surgical procedures versus 36% for the surgical oncology and surgical endoscopy. Charges generated by the provision of surgical critical care, especially in bedside procedures commonly performed in the intensive care unit, exceeded all of the other three surgeons and equaled the revenue generated by operative care. Although overall revenue-generating efficiency was less for the trauma surgeons (57% of eventual collections vs. 67%, &khgr;2p= 0.1), immediate reimbursement for critical care was higher than for any other clinical services.ConclusionThese data demonstrate that subspecialization in surgical critical care provides valid additional earning capacity to surgical practitioners. Reimbursement is at least as good as for traditional operative care, and fees generated can actually exceed revenue from operative care. With impending decreases in global reimbursement, and attempts to unbundle operative fees, this additional capability becomes an important consideration in potential career choice, as well as a major component in the fiscal stability of trauma programs.

ISSN:0022-5282    

出版商:OVID    

年代:2002

数据来源: OVID