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Posttraumatic coagulopathy is a major cause of morbidity. This prospective study evaluated the thrombelastography (TEG) system and PlateletMapping (Haemoscope Corporation, Niles, Ill) values posttrauma, and it correlated those values with transfusions and fatalities. After institutional review board approval, assays were performed on 161 trauma patients. One citrated blood sample was collected onsite (OS), and 1 citrate and 1 heparinized sample were collected within 1 h of arrival to the emergency department (ED). Paired and unpaired t-testing was performed for nominal data with chi square testing for categorical values. Except for a slight increase in clot strength (maximal amplitude (MA)), there were no significant changes from OS to the ED. None of the TEG parameters were significantly different for the 22 patients who required transfusion. PlateletMapping showed lower platelet adenosine diphosphate (ADP) responsiveness in patients who needed transfusions (MA = 22.7 +/- 17.1 vs MA = 35.7 +/- 19.3, P = 0.004) and a correlation of fibrinogen100 mg/dL with fatalities (P = 0.013). For the 14 fatalities, TEG reaction (R) time was 3703 +/- 11,618 versus 270 +/- 393 s (P =0.001), and MA was 46.4 +/- 22.4 versus 64.7 +/- 9.8 mm (P0.001). Hyperfibrinolysis (percent fibrinolysis after 60 min (LY60)15%) was observed in 3 patients in the ED with a 67% fatality rate (P =0.001 by chi-square testing). PlateletMapping assays correlated with the need for blood transfusion. The abnormal TEG System parameters correlated with fatality. These coagulopathies were already evident OS. The TEG assays can assess coagulopathy, platelet dysfunction, and hyperfibrinolysis at an early stage posttrauma and suggest more effective interventions.

Trauma during pregnancy places two lives at risk. Knowledge of risk factors for trauma during pregnancy may improve outcomes.We reviewed the charts of 188 such patients admitted to a Level I trauma center from 1996 to 2004. A comparison was made of injury severity and outcome from a cohort of nonpregnant female trauma patients selected with a similar temporal occurrence and age range.Motor vehicle collisions comprised 160 cases, 67 using a restraint device. Of 84 patients tested, 45 tested positive for intoxicants, 16 positive for 2 or more intoxicants. A significant trend toward less testing through the study period was observed (p = 0.0002). Injury severity was assessed by Revised Trauma Score (RTS). RTS11 or admission to operating room or intensive care units (OR/ICU) classified patients as severely injured. The six maternal fatalities had an RTS11 or OR/ICU disposition. Fetal outcomes included 155 live in utero, 18 live births, and 15 fatalities correlating with injury severity by either criteria (p0.0001). Of the fetal fatalities, 7 occurred with RTS = 12, but only 3 fatalities occurred in the 147 cases not admitted to OR/ICU. Gestational age correlated (p0.0001) with fetal outcomes. The 18 live births had mean gestational ages of 35 +/- 4 weeks as compared with fetal fatalities at 20 +/- 9 weeks, and fetuses alive in utero at 22 +/- 9 weeks gestation. Coagulation tests prothrombin time (PT), international normalized ratio (INR) (both p0.008), and partial thromboplastin time (PTT) (p0.0001) correlated with maternal outcome. A matched cohort of nonpregnancy trauma cases during the same time frame indicated that, despite a significantly higher percentage of severely injured patients, fewer fatalities occurred. This might reflect a greater risk for the pregnant trauma patient.This study of trauma in pregnancy cases revealed a high percentage with risk behaviors. There was a significant trend toward less intoxicant testing in recent years. Coagulation tests were the most predictive of outcomes. Lower gestational age correlated with fetal demise.

Insulin resistance after burn is associated with alterations in postreceptor insulin signaling and abnormal glucose homeostasis. The renin-angiotensin system (RAS) exerts a largely inhibitory role on insulin action and is activated after burn injury. We hypothesized that upregulation of RAS is involved in the development of insulin resistance in burned rats. We examined the possibility that an angiotensin II type 1 (AT1) receptor blocker, losartan, enhances insulin sensitivity and thereby increases glucose tolerance in thermally injured rats. A 30% body surface area burn was induced by immersion of the dorsum into water with a temperature level of 95 degrees C for 15 s. Sham-burned rats were immersed in water with a temperature level of 23 degrees C. Losartan (30 mg/kg per day) or placebo (water) was given by gavage immediately after the burn injury and daily for 3 days postburn injury, resulting in sham-burned, burn placebo, and burn losartan groups. Plasma angiotensin II levels between burn placebo and sham-burned groups were not different 3 days after burn injury. However, losartan significantly increased plasma angiotensin II levels (P0.05), suggesting blockade of the AT1 receptor. An oral glucose tolerance test was performed 3 days postburn injury. There was an increase in the area under the curve for insulin and the glucose insulin index in burn placebo group as compared with sham-burned group, indicating insulin resistance. Losartan treatment abolished the insulin resistance in burn as evidenced by an area under the curve for insulin and glucose insulin index lower than that in the burn placebo group and similar to that in the sham-burned group. This suggests that insulin resistance and glucose intolerance associated with burn injury is, in part, caused by RAS.

BACKGROUND There is a dearth of clinical data regarding the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on long-bone fracture (LBF) healing in the acute trauma setting. The orthopedic community believes that the use of NSAIDs in the postoperative period will result in poor healing and increased infectious complications. We hypothesized that, first, NSAID use would not increase nonunion/malunion and infection rates after LBF. Second, we hypothesized that tobacco use would cause higher rates of these complications. METHODS A retrospective study of all patients with femur, tibia, and/or humerus fractures between October 2009 and September 2011 at a Level 1 academic trauma center was performed . In addition to nonunion/malunion and infection rates, patient records were reviewed for demographic data, mechanism of fracture, type of fracture, tobacco use, Injury Severity Score (ISS), comorbidities, and medications given. RESULTS During the 24-month period, 1,901 patients experienced LBF; 231 (12.1%) received NSAIDs; and 351 (18.4%) were smokers. The overall complication rate including nonunion/malunion and infection was 3.2% (60 patients). Logistic regression analysis with adjusted odds ratios were calculated on the risk of complications given NSAID use and/or smoking, and we found that a patient is significantly more likely to have a complication if he or she received an NSAID (odds ratio, 2.17; 95% confidence interval, 1.15-4.10; p < 0.016) in the inpatient postoperative setting. Likewise, smokers are significantly more likely to have complications (odds ratio, 3.19; 95% confidence interval, 1.84-5.53; p < 0.001). CONCLUSION LBF patients who received NSAIDs in the postoperative period were twice as likely and smokers more than three times likely to suffer complications such as nonunion/malunion or infection. We recommend avoiding NSAID in traumatic LBF. LEVEL OF EVIDENCE Epidemiologic & therapeutic study; level II.

Background: The differentiation of duodenal perforation from duodenal hematoma is not always possible with computed tomography (CT). Our diagnostic guideline has included duodenography to investigate CT findings of periduodenal fluid or wall thickening. However, the utility of duodenography as a diagnostic study in blunt abdominal trauma is not defined. We evaluated duodenography as a diagnostic test in patients with suspected blunt duodenal injuries (BDIs). Methods: During a 10-year period, 96 patients out of 25,608 trauma admissions had CT findings of possible BDI and underwent duodenography. Demographic and clinical data, diagnostic methods, and management were derived from prospectively collected data. CT and duodenography studies were reviewed and correlated with surgical findings and outcome. All CT scans were obtained with intravenous contrast; oral contrast was used in 32 patients. Duodenography was analyzed using the 2 x 2 method and Bayes theorem. Results: Indications for duodenography included periduodenal fluid without extravasation (76%), abnormal duodenal wall thickening (16%), and retroperitoneal extraluminal gas (5%). Eighty-six duodenography studies were reported as normal, six were consistent with hematoma, one was indeterminate, and only three revealed extravasation. Two of these three patients with duodenal perforation had retroperitoneal extraluminal air. Only one patient underwent exploration on the basis of duodenography. No blunt duodenal perforation was diagnosed by CT. Overall, duodenography had sensitivity of 54% and specificity of 98%. For BDIs requiring repair, duodenography sensitivity was only 25%; the false-negative rate was also 25%. Retroperitoneal extraluminal air was a useful sign of duodenal perforation, occurring in two of three patients with BDI and only in one without BDI (p < 0.001). Conclusion: Duodenography has a low sensitivity in patients with suspected BDI by CT findings and is of minimal utility in diagnostic evaluation. Retroperitoneal extraluminal air seen on CT is an important sign of BDI requiring surgical repair.

Background . Tracheobronchial injuries are encountered with increasing frequency because of improvements in prehospital care and early initiation of the Advanced Trauma Life Support protocol. We review our experience with these injuries with the hypothesis that the leading determinant of patient outcome is the time interval to diagnosis. Methods . Patients with tracheobronchial injury were identified from the registry of our level 1 trauma center during a 10-year period ending December 1997. Clinical presentation, diagnostic evaluation, surgical management, and outcome were reviewed. Results . Twenty patients with ten cervical tracheal injuries and ten intrathoracic tracheobronchial injuries were treated. The mechanism of injury involved blunt trauma in 11 and penetrating trauma in 9. All patients underwent surgical debridement and primary repair. Patients with isolated airway injuries were discharged home after a mean hospital stay of 6 days and had no early complications. Three patients had delayed diagnosis (> 24 hours), and all sustained complications including death (1 patient) and multiorgan system failure (2 patients). The overall mortality rate was 15%. Conclusions . Operative management of tracheobronchial injuries can be achieved with acceptable mortality. Independent of mechanism or anatomic location of injury, delay in diagnosis is the single most important factor influencing outcome. Early recognition of tracheobronchial injury and expedient institution of appropriate surgical intervention are essential in these potentially lethal injuries.

A previous report from the authors' institution reported the effectiveness of hepatic packing with absorbable fine mesh (AFMP) for the control of hemorrhage in an animal model with an otherwise lethal hepatic injury. The technique has subsequently been applied to 12 abdominal trauma patients with hemodynamic instability and actively hemorrhaging hepatic injuries. Two patients expired in the operating room owing to uncontrolled hemorrhage from hepatic and associated injuries for a mortality of 16.7%. AFMP was successful in controlling hemorrhage in the remaining 10 patients. Hepatic injuries ranged from grade II to grade V, and all were actively hemorrhaging at the time of exploration. None of the surviving 10 patients experienced early or late recurrent bleeding attributable to the hepatic injuries, and there were no intraabdominal abscesses or late deaths. Liver function studies returned to normal prior to discharge in all surviving patients. Follow-up included serial computed tomographic scans, which demonstrated fibrosis incorporating the mesh packing. Complete resolution of injury and mesh appears to proceed over approximately a 6-month period. AFMP is a safe, effective method for controlling hepatic hemorrhage. It is easy to perform in the operating room, offers an excellent matrix for hemostasis, provides tamponade of bleeding sites, and does not require reoperation for removal of packing material, as is necessary with conventional, nonabsorbable packing techniques.

The multiply injured trauma patient presents a diagnostic and therapeutic challenge: that of discovering all injuries while simultaneously proceeding with resuscitation and maintaining life. Many factors involved in the initial resuscitation of the multiply injured patient, such as altered level of consciousness, hemodynamic instability, or inexperience and diagnostic oversight, may lead to missed injuries. Injuries may be missed at any stage of the management of the trauma patient, including intraoperatively, and may involve all regions of the body. Established protocols in the initial management of the multiply injured patient, such as the primary and secondary surveys of the Advanced Trauma Life Support Course, will minimize the chance of missing immediately life-threatening injuries in the emergency department. A careful intraoperative approach must be used in all patients, but especially in those with hemodynamic instability, so that all areas are examined for possible injury, rather than concentrating simply on what is known to be injured. Use of the tertiary survey, a careful re-examination of the multiply injured trauma patient, especially when he or she awakes, will help detect injuries missed during the initial evaluation. Injuries will be missed. Rather than dismissing these as occurrences that happen only to the inexperienced or incompetent, one should approach the multiply injured trauma patient with both special alertness and the humility necessary to search for diagnostic oversights. This approach will lead to early discovery of missed injuries and will minimize the consequences.

We showed in burn-induced insulin resistance that blockade of angiotension II type I receptors with losartan enhanced whole body insulin sensitivity and increased phosphoserine AKT levels, a critic...

Background: The purpose of this study was to examine the contribution of age and gender to outcome after treatment of blunt splenic injury in adults. Methods: Through the Multi-Institutional Trials Committee of the Eastern Association for the Surgery of Trauma (EAST), 1488 adult patients from 27 trauma centers who suffered blunt splenic injury in 1997 were examined retrospectively. Results: Fifteen percent of patients were 55 years of age or older. A similar proportion of patients ≥ 55 went directly to the operating room compared with patients < 55 (41% vs. 38%) but the mortality for patients ≥ 55 was significantly greater than patients < 55 (43% vs. 23%). Patients ≥ 55 failed nonoperative management (NOM) more frequently than patients < 55 (19% vs. 10%) and had increased mortality for both successful NOM (8% vs. 4%, p < 0.05) and failed NOM (29% vs. 12%, p = 0.054). There were no differences in immediate operative treatment, successful NOM, and failed NOM between men and women. However, women ≥ 55 failed NOM more frequently than women < 55 (20% vs. 7%) and this was associated with increased mortality (36% vs. 5%) (both p < 0.05). Conclusion: Patients ≥ 55 had a greater mortality for all forms of treatment of their blunt splenic injury and failed NOM more frequently than patients < 55. Women ≥ 55 had significantly greater mortality and failure of NOM than women < 55.

The purpose of this study was to define the period of time after which delays in management incurred by investigations cause increased morbidity and mortality. The outcome study is intended to correlate time with death from esophageal causes, overall complications, esophageal related complications, and surgical intensive care unit length of stay.This was a retrospective multicenter study involving 34 trauma centers in the United States, under the auspices of the American Association for the Surgery of Trauma Multi-institutional Trials Committee over a span of 10.5 years. Patients surviving to reach the operating room (OR) were divided into two groups: those that underwent diagnostic studies to identify their injuries (preoperative evaluation group) and those that went immediately to the OR (no preoperative evaluation group). Statistical methods included Fisher's exact test, Student's T test, and logistic regression analysis.The study involved 405 patients: 355 male patients (86.5%) and 50 female patients (13.5%). The mean Revised Trauma Score was 6.3, the mean Injury Severity Score was 28, and the mean time interval to the OR was 6.5 hours. There were associated injuries in 356 patients (88%), and an overall complication rate of 53.5%. Overall mortality was 78 of 405 (19%). Three hundred forty-six patients survived to reach the OR: 171 in the preoperative evaluation group and 175 in the no preoperative evaluation group. No statistically significant differences were noted in the two groups in the following parameters: number of patients, age, Injury Severity Score, admission blood pressure, anatomic location of injury (cervical or thoracic), surgical management (primary repair, resection and anastomosis, resection and diversion, flaps), number of associated injuries, and mortality. Average length of time to the OR was 13 hours in the preoperative evaluation group versus 1 hour in the no preoperative evaluation group (p0.001). Overall complications occurred in 134 in the preoperative evaluation group versus 87 in the no preoperative evaluation group (p0.001), and 74 (41%) esophageal related complications occurred in the preoperative evaluation group versus 32 (19%) in the no preoperative evaluation group (p = 0.003). Mean surgical intensive care unit length of stay was 11 days in the preoperative evaluation group versus 7 days in the no preoperative evaluation group (p = 0.012). Logistic regression analysis identified as independent risk factors for the development of esophageal related complications included time delays in preoperative evaluation (odds ratio, 3.13), American Association for the Surgery of Trauma Organ Injury Scale grade2 (odds ratio, 2.62), and resection and diversion (odds ratio, 4.47).Esophageal injuries carry a high morbidity and mortality. Increased esophageal related morbidity occurs with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, rapid diagnosis and definitive repair should be made a high priority.

Background: Efficacy of chest radiograph protocol after tube thoracostomy tube (CT) removal. Methods: Retrospective review (July of 1995 to July of 1996) of 141 patients with CT followed throughout their hospitalization. Excluded patients died (23 patients) or had thoracotomy (13 patients) before CT removal. Results: A total of 105 patients had 113 CT removed (mean age, 36.9 years; Injury Severity Score = 23.4; CT duration, 5.0 days). Protocol chest radiographs were performed on average at 7.9 and 22.1 hours. Recurrent pneumothorax (RHPTX = new interpleural air) occurring in 12 patients (11%) and persistent pneumothorax (PHPTX = same volume of interpleural air) occurring in 13 patients (12%) caused no clinical problems and were treated without tube replacement. Three patients had symptoms after removal; none had RHPTX. Two patients had clinical signs; one reaccumulated a hemothorax requiring CT replacement, the other improved without replacement. Conclusions: Clinically significant RHPTX/PHPTX after CT removal is infrequent. Signs not symptoms detect CT removal complications. At our institution, chest radiographs are obtained in a delayed manner from protocol and offer no benefit over clinical assessment.

We measured D-dimer and plasminogen activator inhibitor-1 (PAI-1) activity in 45 trauma patients to assess their efficacy in predicting the post-traumatic hemostatic perturbations. We found the correlation between D-dimer measured by Simpli Red test and ELISA to be highly significant (p=0.0001). The D-dimer ELISA indicated that the serial changes of D-dimer after trauma were variable. However, the increases of D-dimer were associated with clinical conditions of the patient, such as trauma surgery, infections, or thrombotic complications. A significant correlation was found for D-dimer levels measured by ELISA versus the injury severity score (ISS) in all the trauma patients on day 1 (p=0.0153) and on day 2 (p=0.0495). The PAI-1 activity was increased at admission and showed a progessive decline from day 2 onward, and the correlation for the daily decline of PAI-1 was highly significant (p=0.0001). The PAI-1 activity and plasminogen activator activity showed a significant negative correlation on days 1, 2, and 3. PAI-1 activity correlated moderately with D-dimer level only on day 1 (p=0.0569). Three out of forty-five patients developed thrombotic complications: one patient who died from pulmonary embolism and two patients who developed adult respiratory distress syndrome (ARDS). In summary: 1) PAI-1 activity and D-dimer exhibited contrasting serial changes after trauma. 2) There was also a negative correlation between PAI-1 activity and PA activity. 3) A significant correlation of D-dimer with ISS confirms, as might be anticipated, that there is increased activation of the coagulation mechanism in severe injury, and suggests that D-dimer levels may prove useful to screen for patients at strong risks of thrombotic complications.

Background: Blunt aortic injury is a major cause of death from blunt trauma. Evolution of diagnostic techniques and methods of operative repair have altered the management and posed new questions in recent years. Methods: This study was a prospectively conducted multicenter trial involving 50 trauma centers in North America under the direction of the Multi-institutional Trial Committee of the American Association for the Surgery of Trauma. Results: There were 274 blunt aortic injury cases studied over 2.5 years, of which 81% were caused by automobile crashes. Chest computed tomography and transesophageal echocardiography were applied in 88 and 30 cases, respectively, and were 75 and 80% diagnostic, respectively. Two hundred seven stable patients underwent planned thoracotomy and repair. Clamp and sew technique was used in 73 (35%) and bypass techniques in 134 (65%). Overall mortality was 31%, with 63% of deaths being attributable to aortic rupture; mortality was not affected by method of repair. Paraplegia occurred postoperatively in 8.7%. Logistic regression analysis demonstrated clamp and sew (p = 0.002) and aortic cross clamp time of 30 minutes (p = 0.01) to be associated with development of postoperative paraplegia. Conclusions: Rupture after hospital admission remains a major problem. Although newer diagnostic techniques are being applied, at this time aortography remains the diagnostic standard. Aortic cross clamp time beyond 30 minutes was associated with paraplegia; bypass techniques, which provide distal aortic perfusion, produced significantly lower paraplegia rates than the clamp and sew approach.

Objective: To determine if cytokine responses and lung injury induced by intravenous (iv) lipopolysaccharide (LPS) at 4 hr were enhanced in rats that had been previously subjected to 30 min of total liver ischemia (Pringle's maneuver) followed by 24 hr or 3 days of reperfusion. Background: Many patients with liver trauma require occlusion of hepatic blood flow to control hemorrhage and facilitate repair. A significant number of these patients subsequently develop the systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction (MOD) characterized by the release of cytokines and tissue neutrophil influx. Macrophages, including Kupffer cells, may be activated by ischemic injury and dysregulation of their response to LPS may contribute to the development of SIRS and acute respiratory distress syndrome. Methods: Adult male Sprague–Dawley rats were randomly divided into six groups: three groups received total hepatic ischemia for 30 min and three groups had a sham procedure. Twenty-four hours or 3 days after hepatic ischemia/reperfusion injury, rats were treated with LPS (5 mg/kg) or saline and monitored for 4 hr. We collected serum, bronchoalveolar lavage (BAL) fluid, and lung tissue. Results: Serum and BAL cytokine concentrations were significantly increased by iv LPS; however, hepatic ischemia/reperfusion injury 24 hr or 3 days before iv LPS ameliorated this cytokine response. The LPS-induced pulmonary neutrophil influx and histopathological changes were similar in sham and hepatic ischemia/reperfusion-injured groups. Conclusions: Hepatic ischemia/reperfusion injury significantly attenuated the serum and BAL cytokine concentrations, but did not change pulmonary neutrophil influx or histopathological alterations in response to iv LPS.

Pathologic thrombosis, in the form of pulmonary embolism (PE) and deep venous thrombosis (DVT), causes significant morbidity and mortality in trauma patients and presents a diagnostic and therapeutic challenge because of associated conditions in these patients. This study examines the measurement of D-dimer crosslinked fibrin degradation products (D-dimer XDPs) as an indicator of hypercoagulability that places a trauma patient at risk of developing pathologic thrombosis. The time course of changes in D-dimer values after trauma normally involves an initial increase with a rapid decrease of D-dimer XDP levels to normal. Patients who then demonstrate a second rise in D-dimer values are at risk for pathologic thrombosis. Forty-one trauma patients were studied, in two groups, to evaluate the potential use of D-dimer XDP levels in evaluating the risk of pathologic thrombosis. A secondary increase in D-dimer XDP levels was found to occur in patients with PE, although sepsis and adult respiratory distress syndrome can also cause a late increase. However, D-dimer determinations appear to provide an easy, relatively inexpensive means of evaluating trauma patients for the risk of pathologic thrombosis.

We measured D-dimer and plasminogen activator inhibitor-1 (PAI-1) activity in 45 trauma patients to assess their efficacy in predicting the post-traumatic hemostatic perturbations. We found the correlation between D-dimer measured by Simpli Red test and ELISA to be highly significant (p=0.0001). The D-dimer ELISA indicated that the serial changes of D-dimer after trauma were variable. However, the increases of D-dimer were associated with clinical conditions of the patient, such as trauma surgery, infections, or thrombotic complications. A significant correlation was found for D-dimer levels measured by ELISA versus the injury severity score (ISS) in all the trauma patients on day 1 (p=0.0153) and on day 2 (p=0.0495). The PAI-1 activity was increased at admission and showed a progessive decline from day 2 onward, and the correlation for the daily decline of PAI-1 was highly significant (p=0.0001). The PAI-1 activity and plasminogen activator activity showed a significant negative correlation on days 1, 2, and 3. PAI-1 activity correlated moderately with D-dimer level only on day 1 (p=0.0569). Three out of forty-five patients developed thrombotic complications: one patient who died from pulmonary embolism and two patients who developed adult respiratory distress syndrome (ARDS). In summary: 1) PAI-1 activity and D-dimer exhibited contrasting serial changes after trauma. 2) There was also a negative correlation between PAI-1 activity and PA activity. 3) A significant correlation of D-dimer with ISS confirms, as might be anticipated, that there is increased activation of the coagulation mechanism in severe injury, and suggests that D-dimer levels may prove useful to screen for patients at strong risks of thrombotic complications.

Occult pneumothorax is defined as a pneumothorax that is detected by abdominal computed tomographic (CT) scanning, but not routine supine screening chest roentgenograms. Forty trauma patients with occult pneumothorax were prospectively randomized to management with tube thoracostomy (n = 19) or observation (n = 21) without regard to the possible need for positive pressure ventilation, to test the hypothesis that tube thoracostomy is unnecessary in this entity. Eight of the 21 patients observed had progression of their pneumothoraces on positive pressure ventilation, with three developing tension pneumothorax. None of the patients with tube thoracostomy suffered major complications as a result of the procedure. Hospital and ICU lengths of stay were not increased by tube thoracostomy. Patients with occult pneumothorax who require positive pressure ventilation should undergo tube thoracostomy.

This study examined a mesh wrap technique that provides effective hepatic tamponade and clinical experience with the technique in 6 patients is reported. Technical feasibility and effectiveness were investigated in 8 miniature swine. The animals were divided into two groups: group A (n = 4), control animals; stellate liver lacerations without mesh wrap or other measures for hemostasis, and group B (n = 4); stellate liver laceration with synthetic absorbable mesh wrap applied for hepatic hemostasis. Except for mesh application, all variables were held constant for both groups. All animals in the control group died within 20 to 120 minutes (mean: 65 minutes). All animals in group B survived (p = 0.029). The livers were harvested for gross and microscopic examinations. No abscess, bile leak, or hematoma was noted. Clinically, total mesh wrapping was attempted in 6 patients with blunt exsanguinating liver injuries. The technique failed intraoperatively in two patients with juxtacaval lacerations and hepatic vein avulsion injuries. One patient with a bilobar gunshot wound died later of sepsis. In three patients with bursting injuries, the technique successfully controlled bleeding and resulted in long-term survival. In conclusion, the total hepatic mesh wrap (1) is geometrically, technically, and mechanically feasible, (2) was not associated with complications in this series, and (3) can effectively secure hemostasis following parenchymal liver injury.

INTRODUCTION Pulmonary edema, or increased lung water, adversely affects gas exchange and pulmonary compliance. Numerous safety factors exist to protect against pulmonary edema and alveolar flooding. The most important of these safety factors is thought to be the lymphatic system, which removes water and protein that filters out of the pulmonary capillaries into the interstitium of the lung [ 131. Controversy has existed with regard to how lymph is propelled through the lymphatic system and cleared from the lungs. Essentially, the question centers on whether extrinsic forces caused by movement of surrounding structures (such as muscles, arteries, heart, or lungs) propels the lymph or whether intrinsic forces (rhythmic contractions of smooth muscle in the lymph vessels) were involved. Hall et al. cannulated lymph vessels throughout the body and discovered that extrinsic forces were minor and superimposed on the major intrinsic pressure waves. This applied everywhere except in the central lymphatic system, where the pressures generated by lung expansion and contraction seemed to be the major force [4]. Respiratory movement has been felt by many to be of primary importance for pulmonary or central lymph flow [7, 11, 12, 151. However, Staub and others have felt that intrinsic forces are the most important [ 12, 141. A relatively recent ventilatory technique, high frequency ventilation (HFV), offers an opportunity to examine the importance of extrinsic respiratory tidal motion on the propulsion of lymph in the pulmonary system [2,3]. High frequency ventilation differs from conventional ventilation by using a much smaller tidal volume (often less than dead space) and higher frequencies. This technique involves minimal bulk flow of air and almost no chest wall motion. High frequency ventilation provides a way to maintain normal blood gases for extended periods of time, while maintaining a decreased or absent tidal movement. We asked the question, does marked reduction of tidal expansion and contraction of the lungs have an effect on the accumulation of EVLW in normal dogs over 48 hr?

High-frequency ventilators (HFV) use increased respiratory rates and decreased tidal volumes to achieve gas exchange similar to conventional mechanical ventilators (CMV). This reverses the relative importance of convection and diffusion to gas exchange. There are currently 3 major types of HFV. They differ from each other in how gas is delivered, how they work, and what physiological effects they have. Conclusions drawn using one type of HFV cannot necessarily be applied to the others. This review examines the different types of HFV as well as the studies that have been conducted using HFV. It stresses the role that HFV may play in the surgical intensive care unit. The one certain indication presently for HFV is in patients with a bronchopleural fistula. It may also be useful as an adjunct to endoscopy and in adult respiratory distress syndrome (ARDS). If the underlying lung disease cannot be reversed (i.e., end-stage fibrotic ARDS), HFV has little to offer.

Nonoperative management of blunt injury to the spleen in adults has been applied with increasing frequency. However, the criteria for nonoperative management are controversial. The purpose of this multi-institutional study was to determine which factors predict successful observation of blunt splenic injury in adults.A total of 1,488 adults (15 years of age) with blunt splenic injury from 27 trauma centers in 1997 were studied through the Multi-institutional Trials Committee of the Eastern Association for the Surgery of Trauma. Statistical analysis was performed with analysis of variance and extended chi2 test. Data are expressed as mean +/- SD; a value of p0.05 was considered significant.A total of 38.5 % of patients went directly to the operating room (group I); 61.5% of patients were admitted with planned nonoperative management. Of the patients admitted with planned observation, 10.8% failed and required laparotomy; 82.1% of patients with an Injury Severity Score (ISS)15 and 46.6% of patients with ISS15 were successfully observed. Frequency of immediate operation correlated with American Association for the Surgery of Trauma (AAST) grades of splenic injury: I (23.9%), II (22.4%), III (38.1%), IV (73.7%), and V (94.9%) (p0.05). Of patients initially managed nonoperatively, the failure rate increased significantly by AAST grade of splenic injury: I (4.8%), II (9.5%), III (19.6%), IV (33.3%), and V (75.0%) (p0.05). A total of 60.9% of the patients failed nonoperative management within 24 hours of admission; 8% failed 9 days or later after injury. Laparotomy was ultimately performed in 19.9% of patients with small hemoperitoneum, 49.4% of patients with moderate hemoperitoneum, and 72.6% of patients with large hemoperitoneum.In this multicenter study, 38.5% of adults with blunt splenic injury went directly to laparotomy. Ultimately, 54.8% of patients were successfully managed nonoperatively; the failure rate of planned observation was 10.8%, with 60.9% of failures occurring in the first 24 hours. Successful nonoperative management was associated with higher blood pressure and hematocrit, and less severe injury based on ISS, Glasgow Coma Scale, grade of splenic injury, and quantity of hemoperitoneum.