A proposed clinical coagulation score for research in trauma-induced coagulopathy.

BACKGROUND: Trauma-induced coagulopathy (TIC) has been the subject of intense study for greater than a century, and it is associated with high morbidity and mortality. The Trans-Agency Consortium for Trauma-Induced Coagulopathy, funded by the National Health Heart, Lung and Blood Institute, was tasked with developing a clinical TIC score, distinguishing between injury-induced bleeding from persistent bleeding due to TIC. We hypothesized that the Trans-Agency Consortium for Trauma-Induced Coagulopathy clinical TIC score would correlate with laboratory measures of coagulation, transfusion requirements, and mortality. METHODS: Trauma activation patients requiring a surgical procedure for hemostasis were scored in the operating room (OR) and in the first ICU day by the attending trauma surgeon. Conventional and viscoelastic (thrombelastography) coagulation assays, transfusion requirements, and mortality were correlated to the coagulation scores using the Cochran-Armitage trend test or linear regression for numerical variables. RESULTS: Increased OR TIC scores were significantly associated with abnormal conventional and viscoelastic measurements, including hyperfibrinolysis incidence, as well as with higher mortality and more frequent requirement for massive transfusion ( p < 0.0001 for all trends). Patients with OR TIC score greater than 3 were more than 31 times more likely to have an ICU TIC score greater than 3 (relative risk, 31.6; 95% confidence interval, 12.7-78.3; p < 0.0001). CONCLUSION: A clinically defined TIC score obtained in the OR reflected the requirement for massive transfusion and mortality in severely injured trauma patients and also correlated with abnormal coagulation assays. The OR TIC score should be validated in multicenter studies. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Does Tranexamic Acid Improve Clot Strength in Severely Injured Patients Who Have Elevated Fibrin Degradation Products and Low Fibrinolytic Activity, Measured by Thrombelastography?

BACKGROUND: Elevated d-dimers in injured patients with paradoxically low fibrinolysis activity measured by viscoelastic assays have been speculated to be "occult" fibrinolysis. However, an alternative explanation is that these patients have previously activated their fibrinolytic system and have shut it down by the time of blood draw, and would gain no benefit in clot strength with tranexamic acid (TXA). We hypothesize that TXA will not increase clot strength in injured patients with low fibrinolytic activity measured by thrombelastography (TEG), despite biomarkers of fibrinolysis activation. STUDY DESIGN: Three TEG assays (rapid, tissue plasminogen activator, and functional fibrinogen) were run on trauma patients. The tissue plasminogen activator TEG served as a functional assay to quantify depletion of fibrinolysis inhibitors (DFI). Patients were stratified by DFI vs non-DFI and then by rapid TEG lysis at 30 minutes phenotype cutoffs. Response to TXA was evaluated with functional fibrinogen TEG by calculating percent change in clot strength with the addition of exogenous TXA in the TEG cup. RESULTS: Six hundred and thirty patients with a median new injury severity score of 20 were analyzed. Depletion of fibrinolysis inhibitors was present in 116 (18%). The DFI patients had significantly increased d-dimer (p < 0.001) and lower fibrinogen (p < 0.001). The DFI patients had increased rates of massive transfusion (33% vs 3.3%; p < 0.001) and mortality (40% vs 6.2%; p < 0.001). Among DFI patients, TXA significantly improved fibrin clot strength with hyperfibrinolysis (+19% clot strength; p < 0.001) but not with shutdown (+1.2%) or physiologic (-2.5%). CONCLUSIONS: Patients with DFI have multiple abnormalities of their coagulation system, but only DFI patients with hyperfibrinolysis have improved fibrin clot strength with TXA.

Is interval appendectomy indicated after non-operative management of acute appendicitis in patients with cancer? A retrospective review from a single institution.

Interval appendectomy (IA) is a controversial subject, with little consensus on its use in patients undergoing treatment for malignancy. We sought to determine the frequency of recurrent appendicitis in cancer patients managed nonoperatively (NOM) during index hospitalization (IHA) for acute appendicitis (AA). Clinical presentation, cancer treatment, and follow-up were collected from electronic medical records of patients with CT scan-confirmed AA treated at a single institution between August 1999 and August 2009. Seventy-two of 109 AA patients underwent appendectomy during IHA; 34 of these 109 were NOM during IHA. Median index length of NOM patients' stay was six days (0-55), median age was 59 (18-80) years. Indications for NOM were presence of abscess or phlegmon (14), mild symptoms (13), high surgical risk (3), end-stage cancer (3), and patient declining surgery (1). Eight NOM patients underwent percutaneous drainage of abdominal abscess (median total duration of intravenous + oral antibiotics = 12 days [0-55]). There were six deaths (1 IHA, 5 NOM): four sepsis and two cancer progression. At a median of 19-month follow-up (range 1-103), four NOM patients surviving IHA had recurrent AA (11.7%) at two (n = 2) and three months (n = 2) after the first episode. Overall, six had IA (17.6%) one to seven months post AA; 25 remained asymptomatic, without IA. In conclusion, among NOM patients at a cancer center at IHA for AA, recurrent AA was early (<4 months) but uncommon. IA should be offered to those with recurrent symptoms, but appears to have a very limited role after several months of asymptomatic follow-up.

Intra-abdominal injury following blunt trauma becomes clinically apparent within 9 hours.

BACKGROUND: The diagnosis of blunt abdominal trauma can be challenging and resource intensive. Observation with serial clinical assessments plays a major role in the evaluation of these patients, but the time required for intra-abdominal injury to become clinically apparent is unknown. The purpose of this study was to determine the amount of time required for an intra-abdominal injury to become clinically apparent after blunt abdominal trauma via physical examination or commonly followed clinical values. METHODS: A retrospective review of patients who sustained blunt trauma resulting in intra-abdominal injury between June 2010 and June 2012 at a Level 1 academic trauma center was performed. Patient demographics, injuries, and the amount of time from emergency department admission to sign or symptom development and subsequent diagnosis were recorded. All diagnoses were made by computed tomography or at the time of surgery. Patient transfers from other hospitals were excluded. RESULTS: Of 3,574 blunt trauma patients admitted to the hospital, 285 (8%) experienced intra-abdominal injuries. The mean (SD) age was 36 (17) years, the majority were male (194 patients, 68%) and the mean (SD) Injury Severity Score (ISS) was 21 (14). The mean (SD) time from admission to diagnosis via computed tomography or surgery was 74 (55) minutes. Eighty patients (28%) required either surgery (78 patients, 17%) or radiographic embolization (2 patients, 0.7%) for their injury. All patients who required intervention demonstrated a sign or symptom of their intra-abdominal injury within 60 minutes of arrival, although two patients were intervened upon in a delayed fashion. All patients with a blunt intra-abdominal injury manifested a clinical sign or symptom of their intra-abdominal injury, resulting in their diagnosis within 8 hours 25 minutes of arrival to the hospital. CONCLUSION: All diagnosed intra-abdominal injuries from blunt trauma manifested clinical signs or symptoms that could prompt imaging or intervention, leading to their diagnosis within 8 hours 25 minutes of arrival to the hospital. All patients who required an intervention for their injury manifested a sign or symptom of their injury within 60 minutes of arrival. LEVEL OF EVIDENCE: Therapeutic study, level IV. Epidemiologic study, level III.

Contemporary predictors of conversion from laparoscopic to open appendectomy.

BACKGROUND: We defined the contemporary conversion rate from laparoscopic appendectomy (LA) to open appendectomy and identified pre-operative factors associated with conversion. METHODS: Retrospective review of 941 consecutive LAs performed for suspected acute appendicitis in a single urban university hospital between 2000 and 2007. Patient characteristics, clinical features, physical examination findings, laboratory values, computed tomography (CT) findings, surgeon identity, operative findings, and pathologic results were assessed. Categorical variables were compared in patients undergoing LA and those in whom conversion was necessary using the Fisher exact test; the Student t-test was used to compare continuous variables. Multivariable analysis was performed with binomial logistic regression. Statistical significance was established at α = 0.05. RESULTS: The overall conversion rate was 4.1% and did not change significantly over the course of the study. By univariable analysis, conversion was significantly associated with older age, male gender, American Society of Anesthesiologists (ASA) score >2 points, longer duration of symptoms, rigidity on physical examination, increased percentage of neutrophils on admission white blood cell differential count, extraluminal air on CT, inexperience of the attending surgeon with LA, retrocecal location of the appendix, gross necrosis or perforation, murky or purulent ascites, and microscopic evidence of perforation. By multivariable analysis, advanced age (hazard ratio [HR] 1.02 per year; 95% confidence interval [CI] 1.01-1.04, p = 0.02), ASA score >2 points (HR 11.2; 95% CI 5.6-24.4; p < 0.001), CT inflammation grade ≥ 4 (HR 4.8; 95% CI 1.9-12.3; p = 0.001), and attending surgeon inexperience (HR 7.4; 95% CI 2.6-20.8; p < 0.001) were independent predictors of conversion. CONCLUSION: The conversion rate during laparoscopic appendectomy has not changed significantly over the past seven years and remains ~4%. Independent pre-operative predictors of conversion are advanced age, ASA score >2 points, attending surgeon inexperience, and extensive inflammation observed on pre-operative CT scan. Proceeding directly with open appendectomy under these circumstances may reduce operative time, expense, and morbidity.

Defining the current negative appendectomy rate: for whom is preoperative computed tomography making an impact?

BACKGROUND: Historically, the negative appendectomy rate (NAR) for patients operated on for acute appendicitis (AA) has exceeded 20%. We sought to define the current NAR with increased use of computed tomography (CT) and laparoscopy. METHODS: Records of 1425 consecutive patients undergoing appendectomy for suspicion of AA during the past 7 years at a single institution were reviewed. The NAR was calculated and compared with earlier data from this institution (1995-1999). Statistical methods included the Fisher exact test and the Student t test; differences of P < .05 were considered statistically significant. RESULTS: The overall NAR was 7.65% compared to 16.3% over the period 1995-1999 (P = .0001), without a change in the perforation rate. Concurrently, the rate of preoperative CT increased from 32% to 95%. CT was associated with a lesser NAR only among adult females (7.6% vs 20.8%, P = .005) but not among adult males or children. No difference in NAR was noted in comparing laparoscopic and open appendectomy. Patients without AA had a greater mean duration of symptoms and lower white blood cell count at presentation than those with AA. Most patients undergoing negative appendectomy had a CT, and more than 50% had CT interpretations that were positive for, or could not exclude, AA. CONCLUSIONS: The NAR in our hospital has decreased progressively to approximately 5%. Although preoperative CT is used in almost all patients, it is only associated with a lesser NAR among adult females. False-positive CTs may contribute to the residual NAR, and further data are needed to determine whether subgroups of male or pediatric patients benefit from preoperative CT.