ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundWe queried an observational database of renal trauma patients to validate the organ injury severity scale (kidney) of the American Association for the Surgery of Trauma (AAST).MethodsIn a retrospective review of our renal trauma database (2,467 patients) with 58 clinical and radiographic patient variables, statistical “classification trees” were used to determine factors predicting need for surgical repair.ResultsScales correlated with the need for surgery (grade I = 0%, grade II = 15%, grade III = 76%, grade IV = 78%, and grade V = 93%) and for nephrectomy (grade I = 0%, grade II = 0%, grade III = 3%, grade IV = 9%, and grade V = 86%). Classification tree analysis (confirmed in 83 additional patients) identified the AAST organ injury severity scale as the most important variable predicting the need for renal repair.ConclusionIn a retrospective review of more than 2,500 patients, we determined that the AAST organ injury severity scale correlates with the need for kidney repair or removal. Classification tree analysis confirmed the scale as the prime variable predicting need for surgical repair.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundThoracic ultrasound may rapidly diagnose pneumothorax when radiographs are unobtainable; the accuracy is not known.MethodsWe prospectively evaluated thoracic ultrasound detection of pneumothorax in patients at high suspicion of pneumothorax. The presence of “lung sliding” or “comet tail” artifacts were determined in patients by ultrasound before radiologic verification of pneumothorax by residents instructed in thoracic ultrasound. Results were compared with standard radiography.ResultsThere were 382 patients enrolled; the cause of injury was blunt (281 of 382), gunshot wound (22 of 382), stab wound (61 of 382), and spontaneous (18 of 382). Pneumothorax was demonstrated on chest radiograph in 39 patients and confirmed by ultrasound in 37 of 39 patients (95% sensitivity); two pneumothoraces could not be diagnosed because of subcutaneous air; the true-negative rate was 100%.ConclusionThoracic ultrasound reliably diagnoses pneumothorax. Expansion of the focused abdominal sonography for trauma (FAST) examination to include the thorax should be investigated for terrestrial and space medical applications.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundRecognition that hypertonic saline (HTS) modulates the inflammatory response has renewed interest in this agent for postinjury resuscitation. Changes in extracellular tonicity alter cell shape and are accompanied by cytoskeletal reorganization. Recent evidence suggests that cytoskeletal reorganization is critical for receptor-mediated signal transduction. We hypothesized that HTS-induced changes in the cytoskeleton interfere with cytotoxic signal transduction.MethodsIsolated neutrophils (PMNs) were incubated in HTS (Na+= 180 mmol/L) and activated withN-formyl-methionyl-leucyl-phenylalanine (receptor-mediated) or phorbol myristate (receptor independent). Actin polymerization was assessed by digital image microscopy and flow cytometry. PMN superoxide anion (O2-) production and p38 MAPK activation was measured by reduction of cytochromecand Western blot. Pretreatment with cytochalasin B was used to disrupt HTS-induced actin reorganization.ResultsHTS inhibited receptor-mediated cytoskeletal reorganization and attenuated p38 MAPK activation and O2-production. HTS had no effect on receptor-independent O2-production. Cytoskeletal disruption (cytochalasin B) prevented HTS attenuation of receptor-mediated p38 MAPK activation.ConclusionHTS attenuates the PMN cytotoxic response by interfering with intracellular signal transduction. Changes in the actin cytoskeleton appear to modulate receptor-mediated p38 MAPK signaling.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundIn response to inflammation, endothelial cytoskeleton rearrangement, cell contraction, and intercellular gap formation contribute to a loss of capillary barrier integrity and resultant interstitial edema formation. The intracellular signals controlling these events are thought to be dependent on intracellular calcium concentration ([Ca2+]i). We hypothesized that, in human pulmonary microvascular endothelial cells, a thrombin-induced increase in permeability to albumin would be dependent on [Ca2+]iand subsequent actin cytoskeleton rearrangements.MethodsHuman lung microvascular endothelial cells, grown on 0.4 &mgr;mol/L pore membranes, were activated with 10 nmol/L human thrombin in Hank’s balanced salt solution/0.5% fetal bovine serum. Select cultures were pretreated (45 minutes) with 4 &mgr;mol Fura-2/AM to chelate Ca2+i. Permeability was assessed as diffusion of bovine serum albumin/biotin across the monolayer. Similarly treated cells were stained with rhodamine-phalloidin to demonstrate actin cytoskeletal morphology. Separately, cells loaded 2 &mgr;mol Fura-2/AM were assessed at OD340/380nmafter thrombin exposure to detect free [Ca2+]i.ResultsIntracellular [Ca2+] levels increased 15-fold (2 seconds) and fell to baseline (10 minutes) after thrombin. Permeability increased 10-fold (30 minutes), and a shift from cortical to actin stress fiber morphology was observed. Chelation of Ca2+idiminished permeability to baseline and reduced the percentage of cells exhibiting stress fiber formation.ConclusionThrombin stimulates pulmonary capillary leak by affecting the barrier function of activated pulmonary endothelial cells. These data demonstrate a thrombin-stimulated increase in monolayer permeability, and cytoskeletal F-actin stress fibers were, in part, regulated by endothelial [Ca2+]i. This early, transient rise in [Ca2+]ilikely activates downstream pathways that more directly affect the intracellular endothelial structural changes that control vascular integrity.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveRecent advances of endovascular stent-grafting (ESG) provide a new therapeutic option with minimum surgical damage for blunt aortic injury (BAI) during its acute phase. To clarify the effectiveness of ESG for BAI, a prospective clinical study at a university hospital was conducted.MethodsAll patients with blunt thoracic injury underwent thoracic contrast-enhanced computed tomographic (CT) scan. Six patients age 48.8 ± 19.8 years, with Injury Severity Scores of 35.8 ± 8.1, and with BAI were treated according to our protocol. The stent-graft covered by woven Dacron was placed at the injury site. Endoleakage was then checked by aortography and CT scan was again performed once a day on days 7 through 14.ResultsAll patients had injury of the aortic isthmus. ESG placement was performed within 8 hours after injury except in one (48 hours). The operating time was 159.5 ± 21.1 minutes and bleeding volume was 105 ± 26.6 mL. No endoleakage was found. Repeat CT scan revealed disappearance of hematoma. All patients except one had an event-free clinical course. One patient died because of rupture of the ascending aorta on day 6; however, autopsy revealed evidence of the healing process at the injury site sealed by ESG.ConclusionAn ESG is a valid therapeutic option with minimal surgical invasion for patients with acute-phase aortic injury.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundPublished contraindications to nonoperative management (NOM) of blunt splenic injury (BSI) include age ≥ 55, Glasgow Coma Scale score ≤ 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.MethodsAll 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.ResultsFive 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 ≥ 55 (p< 0.0006) as being significantly associated with failure. Multivariate analysis identified age ≥ 55 and grades 3 to 5 injuries as independent predictors of failure. The highest failure rates (30–40%) occurred in patients age ≥ 55 with major injury for moderate to large hemoperitoneum. Mortality rates for successful NOM were 12%, and 9% for failed NOM.ConclusionInclusion of all high-risk patients increased the NOM rate while maintaining a low failure rate. Although age ≥ 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 notnecessarilycontraindicate NOM.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundThe true importance of blunt cardiac trauma (BCT) is related to the cardiac complications arising from it. Diagnostic tests that can predict accurately if such complications will develop or not may allow early and aggressive monitoring or early discharge. We investigated the role of two simple and convenient tests, serum cardiac troponin I (cTnI) and electrocardiogram (ECG), when used to identify patients at risk of cardiac complications after BCT.MethodsOver a 10-month period, 115 patients with evidence of significant blunt thoracic trauma were prospectively followed to identify the presence of clinically significant BCT (Sig-BCT), defined as cardiogenic shock, arrhythmias requiring treatment, or structural cardiac abnormalities directly related to the cardiac trauma. An ECG was obtained at admission and at 8 hours. Cardiac troponin I was measured at admission, at 4 hours, and at 8 hours. Transthoracic echocardiography was performed when clinically indicated. The sensitivity, specificity, and positive and negative predictive values of ECG and cTnI to identify Sig-BCT were calculated. Clinical risk factors for Sig-BCT were examined by univariate and multivariate analysis.ResultsNineteen patients (16.5%) were diagnosed with Sig-BCT and, in 18 of them, symptoms presented within 24 hours of admission. Abnormal electrocardiographic findings were detected in 58 patients (50%) and elevated cTnI levels in 27 (23.5%). Electrocardiography and cTnI had positive predictive values of 28% and 48% and negative predictive values of 95% and 93%, respectively. However, when both tests were abnormal (positive) or normal (negative), the positive and negative predictive values increased to 62% and 100%, respectively. Other independent risk factors for Sig-BCT were head injury, spinal injury, history of preexisting cardiac disease, and a chest Abbreviated Injury Score greater than 2.ConclusionThe combination of ECG and cTnI identifies reliably the presence or absence of Sig-BCT. Patients with an abnormal ECG and cTnI need close monitoring for at least 24 hours. Patients with a normal admission ECG and cTnI can be safely discharged in the absence of other injuries.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundThe two-hit theory has emerged as a mechanism to explain the development of organ failure after traumatic injury. We evaluated the effects of exploratory laparotomy (EL) as a second hit on mice after hemorrhage and resuscitation (H/R). Our hypothesis was that mice exposed to prior H/R would demonstrate more evidence of acute lung injury (ALI), as well as an augmented cytokine response, than mice exposed to H/R or EL alone.MethodsThree groups of mice were examined. Mice undergoing H/R alone were labeled as the H/R group. Mice undergoing sham H/R (cannulation but no hemorrhage), followed 5 days later by EL, were labeled as the EL group; and mice undergoing H/R, followed 5 days later by an EL, were labeled as the H/R + EL, or two-hit, group. Respiratory function was determined by using whole-body plethysmography and lung gas diffusion. Serum interleukin-6 (IL-6) and tumor necrosis factor-&agr; (TNF-&agr;) were assayed at 1 and 4 hours after the injury stimuli.ResultsEvaluation of the change in pulmonary function after 24 hours demonstrated that EL alone induces a significant decrease in pulmonary function, whereas two-hit mice did not exhibit a potentiated response. Alveolar function was significantly degraded in the EL group compared with all other groups (p< 0.0001). TNF-&agr; did not change after any injury at any time. However, evaluation of IL-6 levels demonstrated a substantial increase after H/R, EL, and H/R + EL compared with baseline and at 1 hour. Comparison of the three groups at 4 hours did not demonstrate any differences in serum concentrations of IL-6. Histologic evaluation lungs demonstrated that the most severe lung injury was seen in the EL mice.ConclusionIt would appear that serum TNF-&agr; has little impact on the pathogenesis of ALI after EL, whereas serum IL-6 may be more important. Exploratory laparotomy resulted in a significant change in pulmonary function. Contrary to our initial hypothesis, two-hit mice did not demonstrate more evidence of ALI and, in fact, demonstrated less lung injury than EL mice.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundIn previous studies, mild hypothermia (34°C) during uncontrolled hemorrhagic shock (HS) increased survival. Hypothermia also increased mean arterial pressure (MAP), which may have contributed to its beneficial effect. We hypothesized that hypothermia would improve survival in a pressure-controlled HS model and that prolonged hypothermia would further improve survival.MethodsThirty rats were prepared under light nitrous oxide/halothane anesthesia with spontaneous breathing. The rats underwent HS with an initial blood withdrawal of 2 mL/100 g over 10 minutes and pressure-controlled HS at a MAP of 40 mm Hg over 90 minutes (without anticoagulation), followed by return of shed blood and additional lactated Ringer’s solution to achieve normotension. Hemodynamic monitoring and anesthesia were continued to 1 hour, temperature control to 12 hours, and observation without anesthesia to 72 hours. After HS of 15 minutes, 10 rats each were randomized to group 1, with normothermia (38°C) throughout; group 2, with brief mild hypothermia (34°C during HS 15–90 minutes plus 30 minutes after reperfusion); and group 3, with prolonged mild hypothermia (same as group 2, then 35°C [possible without shivering] from 30 minutes after reperfusion to 12 hours).ResultsMAP during HS and initial resuscitation was the same in all three groups, but was higher in the hypothermia groups 2 and 3, compared with the normothermia group 1, at 45 and 60 minutes after reperfusion. Group 1 required less blood withdrawal to maintain MAP 40 mm Hg during HS and more lactated Ringer’s solution for resuscitation. At end of HS, lactate levels were higher in group 1 than in groups 2 and 3 (p< 0.02). Temperatures were according to protocol. Survival to 72 hours was achieved in group 1 by 3 of 10 rats, in group 2 by 7 of 10 rats (p= 0.18 vs. group 1), and in group 3 by 9 of 10 rats (p= 0.02 vs. group 1,p= 0.58 vs. group 2). Survival time was longer in group 2 (p= 0.09) and group 3 (p= 0.007) compared with group 1.ConclusionBrief hypothermia had physiologic benefit and a trend toward improved survival. Prolonged mild hypothermia significantly increased survival after severe HS even with controlled MAP. Extending the duration of hypothermia beyond the acute phases of shock and resuscitation may be needed to ensure improved outcome after prolonged HS.

ISSN:0022-5282    

出版商:OVID    

年代:2001

数据来源: OVID