Biomedical subjects

Mauricio Lynn

Publications and source records attributed to Mauricio Lynn.

7 recordsLinked to original sources

PubMed2003

Tourniquets for hemorrhage control on the battlefield: a 4-year accumulated experience.

BACKGROUND: Tourniquet application is a known means for bleeding prevention in the military prehospital setting. METHODS: This study was a 4-year retrospective analysis of silicone and improvised tourniquet applications by Israeli Defense Force soldiers. RESULTS: Of 550 soldiers who were treated in the prehospital setting, tourniquets were applied to 91 (16%) patients and in less than 15 minutes in 88% of the cases with almost no complications. Penetrating trauma was the main mechanism of injury. The indication was situational and nonmedical in 58 (53%) of the cases. The patients' ischemic time was 83 +/- 52 minutes (range, 1-305 minutes). A total of 78% of applications were effective, with higher success rates for medical staff compared with fellow soldiers and for upper limbs (94%) compared with lower limbs (71%, p < 0.01). CONCLUSION: Tourniquet application is an effective and easily applied (by medical and nonmedical personnel) method for prevention of exsanguination in the military prehospital setting.

Hemorrhage↗

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↗

PubMed2002

Updates in the management of severe coagulopathy in trauma patients.

Coagulopathy is the major cause of bleeding-related mortality in patients who survive the operating room. Its association with hypothermia and metabolic acidosis is common and constitutes a vicious cycle. Usually, post-traumatic coagulopathy is an early event and may be present during surgery. The pathogenesis of severe post-traumatic coagulopathy is complex and multifactorial. Virtually every aspect of the normal coagulation cascade is affected in the cold, acidotic, exsanguinating trauma patient. In the last decade many surgeons have emphasized the role of prevention or early treatment of this vicious cycle. Damage control surgery with planned re-operations has demonstrated superiority over the traditional approach in cases where the patients' condition is deteriorating. Early control of surgical bleeding and significant contamination, together with vigorous correction of hypothermia and continuous resuscitation, has improved the survival of these patients. Recently, a new adjunct to the treatment of coagulopathy in trauma patients has been reported and is undergoing controlled animal trials. Recombinant activated factor VII (rFVIIa) was originally developed as a pro-hemostatic agent for the treatment of bleeding episodes in hemophilia patients. rFVIIa has been successfully used in moribund trauma patients in whom standard procedures had failed to correct bleeding. Preliminary preclinical and clinical studies are under way.

Blood Loss, Surgical↗

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

Does prehospital fluid administration impact core body temperature and coagulation functions in combat casualties?

BACKGROUND: Administration of large amounts of fluids to trauma patients, in the absence of surgical control, may increase bleeding, cause hypothermia and coagulopathy which may worsen the bleeding and increase morbidity and mortality. The purpose of our study is to examine the impact of prehospital fluid administration to military combat casualties on core body temperature and coagulation functions. METHODS: Prospective data were collected on all cases of moderately (9 < or = ISS < or = 14) and severely (ISS > or = 16) injured victims wounded in South Lebanon, treated by Israeli military physicians and evacuated to hospitals in Israel, over a two-year period. Data regarding prehospital phase of injury (timetables, amount of fluids) and upon hospital arrival (initial core body temperature, prothrombin time [PT], partial thromboplastin time [PTT]) were examined for monotonic relation using Spearman's non-parametric test. RESULTS: Fifty-three moderately injured and 31 severely injured patients were included in the study. The average evacuation time for the moderately injured group was 109.3 +/- 44.8 min, and for the severely injured 100.3 +/- 38.4 min (P value=NS). The mean volume of fluids administered was 2.39 +/- 1.52 and 2.49 +/- 1.47 l, respectively (P=NS). No statistical correlation was found between core body temperature, PT or PTT, measured upon hospital arrival, and prehospital fluid treatment. In addition, no correlation was found between core body temperature on hospital arrival and prehospital time, or between prehospital fluid volumes and prehospital time. The mean core body temperature of the moderately injured patients was 36.8 degrees C, and that of severely injured was 35.8 degrees C (P=0.026). CONCLUSIONS: With proper control of blood loss and avoidance of excessive fluid administration, moderately and severely injured combat casualties in 'low intensity conflict' in South Lebanon can be resuscitated with fluid volumes that do not result in a coagulation deficit or hypothermia. The core body temperature on arrival at the hospital is related to the severity of the injury.

Blood Coagulation↗

PubMed2002

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

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↗