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Stephen M Cohn

Publications and source records attributed to Stephen M Cohn.

17 recordsLinked to original sources
PubMed2003

Pro/con clinical debate: antibiotics are important in the management of patients with pancreatitis with evidence of pancreatic necrosis.

Pancreatitis is not an infrequent diagnosis in patients admitted to the intensive care unit. Prolonged stays, intense resource utilization and high morbidity/mortality are commonplace in such patients. Management for the most part is supportive, with the surgical team keeping close watch to intervene as the need arises. Over the past few decades there has been considerable debate regarding the usefulness of systemic antibiotics to prevent infectious complications in patients with evidence of pancreatic necrosis. In the present article of Critical Care, two expert groups debate the two sides of this contentious antibiotic issue.

Adult↗
PubMed2003

Oxygen therapeutics in trauma and surgery.

A number of oxygen therapeutics have completed safety trials and are now undergoing efficacy evaluation in multicenter phase III trials in North America and Europe. There are numerous potential advantages of these solutions when compared with packed red blood cells. They are readily available and have a long shelf life; do not require type and cross-matching; are virtually free of viral or bacterial contamination; have a much lower viscosity than blood; and may lack the immunosuppressive effects of blood. These products may also deliver more oxygen per unit mass than an equivalent amount of hemoglobin from red blood cells, providing the potential to sustain life in certain clinical situations. A few problems remain, including short biologic half-life, which may limit the application to times when the patient is most acutely anemic (i.e., in the intraoperative or immediate perioperative phase) or for emergent use. Nevertheless, a safe, effective alternative therapy providing oxygen delivery characteristics comparable to red blood cells may soon be available that could have significant impact on the way that we resuscitate trauma patients.

Blood Substitutes↗
PubMed2003

The risk of death for Jehovah's Witnesses after major trauma.

BACKGROUND: Trauma surgeons are faced with life-threatening blood loss in patients such as Jehovah's Witnesses. We assessed and compared the risks of death after major trauma for Jehovah's Witnesses and other religious groups. METHODS: A retrospective cohort study was conducted between August 1992 and September 1999 in a Level I academic trauma center. Statistical methods included Tukey's one-way analysis of variance, chi2 analysis, and bivariate and multivariate logistic regression analyses. RESULTS: The cohort consisted of 556 patients: 82 Jehovah's Witnesses (14.7%), 52 Baptists (9.4%), 101 Catholics (18.2%), and 321 patients belonging to other religious groups (57.7%). Mean Injury Severity Scores for 433 patients were 10.3 +/- 9, 8.9 +/- 10, 10.3 +/- 11, and 11.3 +/- 14, respectively. There were no significant differences in mean Injury Severity Scores between religious groups, and no statistically significant associations between religion and Injury Severity Scores were identified. Significant predictors of mortality were age, systolic blood pressure at admission, Glasgow Coma Scale score, and type of trauma. Jehovah's Witnesses were 6% more likely to die after major trauma than Baptists, 20% more likely than Catholics, and as likely as patients from any other religious groups. CONCLUSION: After controlling for age, race, systolic blood pressure, Glasgow Coma Scale score, and type of trauma, Jehovah's Witnesses have a nonsignificant increased risk of death after major trauma compared with other religious groups.

Adolescent↗
PubMed2003

Predicting the need for laparotomy in pediatric trauma patients on the basis of the ultrasound score.

BACKGROUND: It is possible to quantify the amount of hemoperitoneum seen on focused assessment with sonography for trauma (FAST) using a simple scoring system that had previously been shown to correlate with the need for subsequent laparotomy in adults. A score of 3 or greater was shown to be highly accurate in predicting the need for laparotomy. We hypothesized that this scoring system might also predict the need for laparotomy in pediatric trauma patients. METHODS: We retrospectively reviewed all records for patients 15 years and younger who underwent FAST after blunt trauma. A "positive" ultrasound examination was defined as one containing free intraperitoneal fluid with or without solid organ injury. The ultrasound score (USS) was defined as the depth of the deepest pocket of fluid collection measured in centimeters plus the number of additional spaces where fluid was seen. RESULTS: Thirty-eight (19.6%) of 193 patients who had FAST performed had positive ultrasound examinations. Thirty-seven patients with complete records were analyzed. There were no differences between patients with a USS < or = 3.0 and those with a USS > 3.0 in terms of admission pulse, Glasgow Coma Scale score, Injury Severity Score, or the proportion of patients who were initially hypotensive. One of 22 patients with a USS < or = 3.0 required therapeutic laparotomy versus 8 of 15 patients with a USS > 3.0 ( = 0.002). For a USS > 3.0, sensitivity, specificity, and accuracy in predicting therapeutic laparotomy were 89%, 75%, and 78%, respectively. CONCLUSION: Ultrasound quantification of hemoperitoneum by a simple scoring system may serve as a useful adjunct to traditional clinical parameters in predicting the need for subsequent laparotomy in pediatric patients. Prospective validation with a larger study is required.

Adolescent↗
PubMed2003

Early coagulopathy predicts mortality in trauma.

BACKGROUND: Coagulopathy and hemorrhage are known contributors to trauma mortality; however, the actual relationship of prothrombin time (PT) and partial thromboplastin time (PTT) to mortality is unknown. Our objective was to measure the predictive value of the initial coagulopathy profile for trauma-related mortality. METHODS: We reviewed prospectively collected data on trauma patients presenting to a Level I trauma center. A logistic regression analysis was performed of PT, PTT, platelet count, and confounders to determine whether coagulopathy is a predictor of all-cause mortality. RESULTS: From a trauma registry cohort of 20103 patients, 14397 had complete disposition data for initial analysis and 7638 had complete data for all variables in the final analysis. The total cohort was 76.2% male, the mean age was 38 years (range, 1-108 years), and the median Injury Severity Score was 9. There were 1276 deaths (all-cause mortality, 8.9%). The prevalence of coagulopathy early in the postinjury period was substantial, with 28% of patients having an abnormal PT (2994 of 10790) and 8% of patients having an abnormal PTT (826 of 10453) on arrival at the trauma bay. In patients with disposition data and a normal PT, 489 of 7796 died, as compared with 579 of 2994 with an abnormal PT (6.3% vs. 19.3%; chi2 = 414.1, p < 0.001). Univariate analysis generated an odds ratio of 3.6 (95% confidence interval [CI], 3.15-4.08; p < 0.0001) for death with abnormal PT and 7.81 (95% CI, 6.65-9.17; p < 0.001) for deaths with an abnormal PTT. The PT and PTT remained independent predictors of mortality in a multiple regression model, whereas platelet count did not. The model also included the independent risk factors age, Injury Severity Score, scene and trauma-bay blood pressure, hematocrit, base deficit, and head injury. The model generated an adjusted odds ratio of 1.35 for PT (95% CI, 1.11-1.68; p < 0.001) and 4.26 for PTT (95% CI, 3.23-5.63; p < 0.001). CONCLUSION: The incidence of coagulation abnormalities, early after trauma, is high and they are independent predictors of mortality even in the presence of other risk factors. An initial abnormal PT increases the adjusted odds of dying by 35% and an initial abnormal PTT increases the adjusted odds of dying by 326%.

Adult↗
PubMed2003

Modified rapid deployment hemostat bandage reduces blood loss and mortality in coagulopathic pigs with severe liver injury.

BACKGROUND: Hemostasis can be difficult to achieve after blunt abdominal trauma, especially if the patient is coagulopathic. The U.S. Food and Drug Administration has recently approved a hemostatic dressing for treating bleeding after extremity trauma (RDH bandage; Marine Polymer Technologies, Cambridge, MA). It has not been evaluated for internal bleeding after trauma. We redesigned this dressing for internal use, and then tested whether this modified bandage (Miami-modified Rapid Deployment Hemostat) could achieve hemostasis when used as an adjunct to standard laparotomy pad packing in a pig model of severe liver injury with coagulopathy. METHODS: Anesthetized swine (35-45 kg) received an isovolemic 45% blood volume replacement with refrigerated Hextend (6% hetastarch). Core body temperature was maintained at 33-34 degrees C with intra-abdominal ice packs. A coagulopathic condition was documented by thromboelastography. At this point a severe liver injury was induced by the avulsion of the left lateral hepatic lobe, then the pigs were randomized to treatment with either standard abdominal packing (control) or packing plus Miami-modified Rapid Deployment Hemostat. Two series of experiments were conducted. In series one (n = 14), the abdomen was closed and the animals were observed with no resuscitation. After one hour, the abdomen was opened, the packing was removed and the presence of bleeding was noted. In series two (n = 10), the abdomen was closed and the animal resuscitated with one unit of blood plus as much lactated Ringers intravenous fluid (IVF) as required to maintain a mean arterial pressure (MAP) > 70 mm Hg. After one hour, the packing was removed, the abdomen closed, and data were collected for an additional two hours. RESULTS: Series one: 6/7 animals in the control group had continued bleeding at one hour; 1/7 animals in the treatment group had active bleeding (p = 0.0291). Series two: With control vs. Miami-modified Rapid Deployment Hemostat, the three-hour survival was zero vs. 80% (p = 0.0476). The total blood loss was 1.2 +/- 0.1 vs. 0.3 +/- 0.1 mL/kg/min (p = 0.001) and the IVF requirement was 1.6 +/- 0.3 vs. 0.6 +/- 0.3 mL/kg/min (p = 0.026). CONCLUSIONS: The Miami-modified Rapid Deployment Hemostat bandage significantly reduced mortality, blood loss, and fluid requirements when used as an adjunct to standard abdominal packing following severe liver injury in coagulopathic pigs [corrected].

Animals↗
PubMed2003

Gastric tonometry: the role of mucosal pH measurement in the management of trauma.

Effective management of hemorrhagic shock depends on titration of therapies against reliable resuscitation end points. Conventional clinical and laboratory indexes of shock are often slow to respond to progressive circulatory compromise. GI mucosal ischemia resulting from redistribution of blood flow may, however, precede uncompensated shock and may compound the initial hemorrhagic insult by touching off cascades of inflammatory responses. Trauma patients with evidence of subclinical GI ischemia have been shown to have poor outcomes. Gastric tonometry, by detecting the presence of gastric intramucosal acidosis as a proxy of splanchnic hypoperfusion, may facilitate more timely and rational shock resuscitation. This article reviews the development and validation of gastric tonometry and summarizes the clinical studies that have used this modality to guide the management of shock in trauma patients.

Carbon Dioxide↗
PubMed2002

The incision of choice for pregnant women with appendicitis is through McBurney's point.

BACKGROUND: There is uncertainty over the optimal incision for gravid patients with appendicitis. METHODS: Data were collected retrospectively from January 1, 1995, through December 31, 2000, on 374 women of childbearing age who underwent appendectomies. Of these, 23 gravid patients were evaluated. RESULTS: Eighteen incisions were made over McBurney's point and five were created superior to McBurney's point. Patients in the third trimester of pregnancy all received incisions over McBurney's point. The appendix was located without difficulty in all 4 of the third trimester patients. The appendix was easily located in 94% of the incisions made through McBurney's point and 80% of the incisions made above McBurney's point. CONCLUSIONS: Our clinical experience indicates that the incision for the removal of the appendix in pregnant patients in all trimesters can be successfully made over McBurney's point.

Abdomen↗
PubMed2002

Unexpected findings in trauma patients dying in the intensive care unit: results of 153 consecutive autopsies.

BACKGROUND: The true incidence of missed injuries in trauma-related deaths is unknown, because in only about 60% of injury-related deaths nationwide is an autopsy performed. Few studies have documented the frequency of missed diagnoses leading to deaths specifically in the trauma ICU population. We attempted to evaluate the incidence and nature of missed injuries and complications in trauma- and burn-related deaths in our ICU given an autopsy rate of close to 100%. STUDY DESIGN: The medical records of all trauma- and burn-related deaths in the ICU over a 2-year period were reviewed retrospectively. Missed diagnoses were classified as class 1: major diagnosis that if recognized and treated appropriately might have changed outcomes; class II: major diagnosis that if recognized and treated appropriately would not have changed outcomes; and class III: minor diagnosis. RESULTS: Complete antemortem records were available for 158 patients, of which 153 (97%) underwent autopsy. Mean age was 50 years, and 72% were males. Mean ICU stay was 10 15 days. Four (3%) patients had class I missed diagnoses: bowel infarction, meningitis, retroperitoneal abscess, and bleeding gastric ulcer. Twenty-five (16%) patients had class II diagnoses, and 12 (8%) patients had class III diagnoses. Overall, 81% of 153 patients had either class III diagnoses or no missed injuries or complications. Pneumonia was the most common missed diagnosis. CONCLUSIONS: With an autopsy rate of 97%, 3% of deaths bad missed major diagnoses that might have affected outcomes if recognized antemortem. Autopsy findings can still provide valuable feedback in Improving the quality of care of critically ill trauma patients.

Autopsy↗
PubMed2002

Low-pressure laparoscopy may ameliorate intracranial hypertension and renal hypoperfusion.

BACKGROUND: Increased abdominal pressure is associated with elevations in the intracranial pressure (ICP) and impaired renal function. These adverse effects are potentially important in clinical situations such as severe abdominal trauma and laparoscopic donor nephrectomy. It was hypothesized that the secondary elevation of ICP leads to release of vasoconstrictors, which may affect renal function by decreasing the renal blood flow (RBF). We investigated the effect of laparoscopy on ICP and renal blood flow in a porcine model. MATERIALS AND METHODS: The abdominal pressure of swine (N = 5; 20-25 kg) was gradually increased from baseline to 5, 15, and 25 mm Hg by insufflation of nitrogen into the abdominal cavity. The ICP was measured using a Camino monitor, and RBF was simultaneously measured using a Transonic Doppler probe placed on the renal artery. Results were analyzed using repeated measures ANOVA and the paired t-test. RESULTS: No significant change from baseline was observed in ICP and RBF when the abdominal pressure was 5 mm Hg. However, both ICP and RBF were affected by increasing the abdominal pressure to 15 and 25 mm Hg (P = 0.035 and 0.04 for ICP and P = 0.074 and 0.034 for RBF, respectively). CONCLUSIONS: Low-pressure laparoscopy may reduce the adverse effects of pneumoperitoneum on ICP and RBF. It may be advisable to use low pressures in laparoscopic surgery, especially when changes in ICP or renal perfusion may have significant clinical implications.

Analysis of Variance↗
PubMed2002

The impact of a repealed motorcycle helmet law in Miami-Dade County.

OBJECTIVE: To study the impact of helmet nonuse in motorcycle crashes after the repeal of a mandatory helmet law in the state of Florida. METHODS: We prospectively studied all patients evaluated at the University of Miami/Jackson Memorial Medical Center from July 1, 2000, through December 31, 2000, involved in motorcycle crashes, and compared them with those seen during the same time period the year before the helmet law change. RESULTS: In 1999, before the repeal of the helmet law, there were 52 cases evaluated at our center compared with 94 after the law change. Helmet usage decreased from 1999 (83%) to 2000 (56%). The number of brain injuries (Abbreviated Injury Scale score > or = 2) during this same time period increased from 18 to 35, and the number of fatalities from 2 to 8. CONCLUSION: The repeal of a motorcycle helmet law significantly increased the number and severity of brain injuries admitted to our trauma center.

Accidents, Traffic↗
PubMed2002

Early use of recombinant factor VIIa improves mean arterial pressure and may potentially decrease mortality in experimental hemorrhagic shock: a pilot study.

BACKGROUND: Recombinant factor VIIa (rFVIIa) is used for treatment of bleeding episodes in hemophilia patients who develop inhibitors to factors VIII and IX. We tested the hypothesis that administration of rFVIIa early after injury would decrease bleeding and improve survival after experimental hepatic trauma. METHODS: Anesthetized swine were cannulated for blood sampling and hemodynamic monitoring. Avulsion of left median lobe of the liver induced uncontrolled hemorrhage. After a 10% reduction of mean arterial pressure, animals were blindly randomized to receive intravenous rFVIIa (180 microg/kg) (n = 6) or placebo (n = 7). RESULTS: Mortality was 43% (three of seven) in controls versus 0% with rFVIIa (p = 0.08, chi2). Significantly shorter prothrombin time and higher mean arterial pressures were observed in the rFVIIa group. CONCLUSION: Intravenous administration of rFVIIa early after induction of hemorrhage shortens prothrombin time and improves mean arterial pressure. A trend toward improved survival was observed.

Animals↗
PubMed2002

Early injection of high-dose recombinant factor VIIa decreases blood loss and prolongs time from injury to death in experimental liver injury.

BACKGROUND: Recombinant factor VIIa (rFVIIa) is used for treatment of bleeding episodes in hemophilia patients who develop inhibitors to factors VIII and IX. We tested the hypothesis that administration of rFVIIa early after injury would decrease bleeding and prolong the time from injury to death after experimental hepatic trauma. METHODS: Anesthetized swine were cannulated for blood sampling and hemodynamic monitoring. Avulsion of the left median lobe of the liver induced uncontrolled hemorrhage. After a 10% reduction in mean arterial pressure, animals (n = 8 per group) were blindly randomized to receive intravenous rFVIIa 180 microg/kg, rFVIIa 720 microg/kg, or placebo. Pathologic examination of brain, lung, kidney, heart, and small bowel was performed to assess intravascular thrombosis. RESULTS Mortality during the first hour was 50% (four of eight) in controls versus 0% with rFVIIa 720 microg/kg (p = 0.02, chi2). Blood loss was decreased in the rFVIIa 720 microg/kg group versus the placebo group (13.2 +/- 5.5 mL/kg vs. 21.9 +/- 7.7 mL/kg;p = 0.0223). Time from injury to death was significantly prolonged in the rFVIIa 720 microg/kg group compared with placebo (116 minutes vs. 8.5 +/- 3.5 minutes; p= 0.02). No macro- or microthrombi in vital organs were identified on pathologic examination. CONCLUSION: Intravenous administration of high-dose rFVIIa early after induction of hemorrhage decreased bleeding and prolonged survival. No evidence of thrombosis in vital organs was observed.

Analysis of Variance↗
PubMed2002

When should a chest radiograph be obtained after chest tube removal in mechanically ventilated patients? A prospective study.

BACKGROUND: The purpose of this study was to determine the appropriate time interval between the removal of a chest tube and the chest radiograph (CXR). We hypothesized that a CXR obtained 1 hour after chest tube removal would exclude the presence of a recurrent pneumothorax. METHODS: Of 214 trauma intensive care unit patients with a chest tube during a 1-year period, 75 met entry criteria and underwent chest tube removal according to an institutional review board-approved prospective study protocol. Patients were undergoing positive-pressure ventilation, with an existing solitary chest tube, and had less than 150 mL of drainage on water seal over the previous day. After chest tube removal, serial CXRs were obtained at approximately 1, 10, and 36 hours. Demographic, chest tube, and ventilator data were collected. RESULTS: None of the patients experienced hemodynamic or respiratory deterioration after chest tube removal. There were nine pneumothoraces (12%). All pneumothoraces were present on the initial CXR after chest tube removal. Two patients (3%) required intervention for pneumothorax. Of the remaining seven small pneumothoraces, three resolved and four were unchanged on the third CXR. CONCLUSION: A CXR obtained within 1 to 3 hours after chest tube removal effectively identifies pneumothorax in mechanically ventilated patients.

Adolescent↗