Mayur Narayan

Haemorrhage control in severely injured patients

Most surgeons have adopted damage control surgery for severely injured patients, in which the initial operation is abbreviated after control of bleeding and contamination to allow ongoing resuscitation in the intensive-care unit. Developments in early resuscitation that emphasise rapid control of bleeding, restrictive volume replacement, and prevention or early management of coagulopathy are making definitive surgery during the first operation possible for many patients. Improved topical haemostatic agents and interventional radiology are becoming increasingly useful adjuncts to surgical control of bleeding. Better understanding of trauma-induced coagulopathy is paving the way for the replacement of blind, unguided protocols for blood component therapy with systemic treatments targeting specific deficiencies in coagulation. Similarly, treatments targeting dysregulated inflammatory responses to severe injury are under investigation. As point-of-care diagnostics become more suited to emergency environments, timely targeted intervention for haemorrhage control will result in better patient outcomes and reduced demand for blood products. Our Series paper describes how our understanding of the roles of the microcirculation, inflammation, and coagulation has shaped new and emerging treatment strategies.

Health systems and services: the role of acute care

As populations continue to grow and age, there will be increasing demand for acute curative services responsive to life-threatening emergencies, acute exacerba -tion of chronic illnesses and many routine health problems that nevertheless require prompt action. Emergency interven-tions and services should be integrated with primary care and public health measures to complete and strengthen health systems. This paper focuses on acute care within that context. First, we draw on standard World Health Organi -zation (WHO) terminology to propose working terms to define “acute care”. Second, we highlight the fragmentation of service delivery that results from not adopting the proposed definition. Third, we show the potential contribution of acute care to integrated health systems designed to reduce all-cause morbidity and mortality. Finally, we propose key steps to further the development of acute care that leaders, researchers and health workers, who are the people responsible for maintaining strong national health systems, should consider taking.

Automated Prediction of Early Blood Transfusion and Mortality in Trauma Patients

BACKGROUND Prediction of blood transfusion needs and mortality for trauma patients in near real time is an unrealized goal. We hypothesized that analysis of pulse oximeter signals could predict blood transfusion and mortality as accurately as conventional vital signs (VSs). METHODS Continuous VS data were recorded for direct admission trauma patients with abnormal prehospital shock index (SI = heart rate [HR] / systolic blood pressure) greater than 0.62. Predictions of transfusion during the first 24 hours and in-hospital mortality using logistical regression models were compared with DeLong’s method for areas under receiver operating characteristic curves (AUROCs) to determine the optimal combinations of prehospital SI and HR, continuous photoplethysmographic (PPG), oxygen saturation (SpO2), and HR-related features. RESULTS We enrolled 556 patients; 37 received blood within 24 hours; 7 received more than 4 U of red blood cells in less than 4 hours or “massive transfusion” (MT); and 9 died. The first 15 minutes of VS signals, including prehospital HR plus continuous PPG, and SpO2 HR signal analysis best predicted transfusion at 1 hour to 3 hours, MT, and mortality (AUROC, 0.83; p < 0.03) and no differently (p = 0.32) from a model including blood pressure. Predictions of transfusion based on the first 15 minutes of data were no different using 30 minutes to 60 minutes of data collection. SI plus PPG and SpO2 signal analysis (AUROC, 0.82) predicted 1-hour to 3-hour transfusion, MT, and mortality no differently from pulse oximeter signals alone. CONCLUSION Pulse oximeter features collected in the first 15 minutes of our trauma patient resuscitation cohort, without user input, predicted early MT and mortality in the critical first hours of care better than the currently used VS such as combinations of HR and systolic blood pressure or prehospital SI alone. LEVEL OF EVIDENCE Therapeutic/prognostic study, level II.

Failure to Clear Elevated Lactate Predicts 24-Hour Mortality in Trauma Patients

BACKGROUND Lactate clearance is a standard resuscitation goal in patients in nontraumatic shock but has not been investigated adequately as a tool to identify trauma patients at risk of dying. Our objective was to determine if trauma patients with impaired lactate clearance have a higher 24-hour mortality rate than patients whose lactate concentration normalizes. METHODS A retrospective chart review identified patients who were admitted directly from the scene of injury to an urban trauma center between 2010 and 2013 and who had at least one lactate concentration measurement within 24 hours. Transfers, patients without lactate measurement, and those who were dead on arrival were excluded. Of the 26,545 screened patients, 18,304 constituted the initial lactate measurement population, and 3,887 were the lactate clearance cohorts. RESULTS Initial lactate had an area under the receiver operating characteristic curve of 0.86 and 0.73 for mortality at 24 hours and in the hospital, respectively. An initial concentration of 3 mmol/L or greater had a sensitivity of 0.86 and a specificity of 0.73 for mortality at 24 hours. The mortality rate among patients with elevated lactate concentrations (n = 2,381; 5.6 [2.8] mmol/L) that did not decline to less than 2.0 mmol/L in response to resuscitative efforts (mean [SD] second measurement, 3.7 [1.9] mmol/L) was nearly seven times higher (4.1% vs. 0.6%, p < 0.001) than among those with an elevated concentration (n = 1,506, 5.3 [2.7] mmol/L) that normalized (1.4 [0.4] mmol/L). Logistic regression analysis showed that failure to clear lactate was associated with death more than any other feature (odds ratio, 7.4; 95% confidence interval, 1.5–35.5), except having an Injury Severity Score (ISS) greater than 25 (odds ratio, 8.2; 95% confidence interval, 2.7–25.2). CONCLUSION Failure to clear lactate is a strong negative prognostic marker after injury. An initial lactate measurement combined with a second measurement for high-risk individuals might constitute a useful method of risk stratifying injured patients. LEVEL OF EVIDENCE Prognostic study, level III.

Angiographic embolization for hemorrhage following pelvic fracture: Is it "time" for a paradigm shift?

Introduction Major pelvic disruption with hemorrhage has a high rate of lethality. Angiographic embolization remains the mainstay of treatment. Delays to angiography have been shown to worsen outcomes in part because time spent awaiting mobilization of resources needed to perform angiography allows ongoing hemorrhage. Alternative techniques like pelvic preperitoneal packing and aortic balloon occlusion now exist. We hypothesized that time to angiographic embolization at our Level 1 trauma center would be longer than 90 minutes. Methods A retrospective review was performed of patients with pelvic fracture who underwent pelvic angiography at our trauma center over a 10-year period. The trauma registry was queried for age, sex, injury severity score, hemodynamic instability (HI) on presentation, and transfusion requirements within 24 hours. Charts were reviewed for time to angiography, embolization, and mortality. Results A total of 4712 patients were admitted with pelvic fractures during the study period, 344 (7.3%) underwent pelvic angiography. Median injury severity score was 29. Median 24-hour transfusion requirements were five units of red blood cells and six units of fresh frozen plasma. One hundred fifty-one patients (43.9%) presented with HI and 104 (30%) received massive transfusion (MT). Median time to angiography was 286 minutes (interquartile range, 210–378). Times were significantly shorter when stratified for HI (HI, 264 vs stable 309 minutes; p = 0.003), and MT (MT, 230 vs non-MT, 317 minutes; p < 0.001), but still took nearly 4 hours. Overall mortality was 18%. Hemorrhage (35.5%) and sepsis/multiple-organ failure (43.5%) accounted for most deaths. Conclusion Pelvic fracture hemorrhage remains a management challenge. In this series, the median time to embolization was more than 5 hours. Nearly 80% of deaths could be attributed to early uncontrolled hemorrhage and linked to delays in hemostasis. Earlier intervention by Acute Care Surgeons with techniques like preperitoneal packing, aortic balloon occlusion, and use of hybrid operative suites may improve outcomes. Level of Evidence Therapeutic study, level V.

Increased ICU resource needs for an academic emergency general surgery service

Objective:ICU needs of nontrauma emergency general surgery patients are poorly described. This study was designed to compare ICU utilization of emergency general surgery patients admitted to an acute care emergency surgery service with other general surgery patients. Our hypothesis is that tertiary care emergency general surgery patients utilize more ICU resources than other general surgical patients. Design:Retrospective database review. Setting:Academic, tertiary care, nontrauma surgical ICU. Patients:All patients admitted to the surgical ICU over age 18 between March 2004 and June 2012. Interventions:None. Measurements and Main Results:Six thousand ninety-eight patients were evaluated: 1,053 acute care emergency surgery, 1,964 general surgery, 1,491 transplant surgery, 995 facial surgery/otolaryngology, and 595 neurosurgery. Acute care emergency surgery patients had statistically significantly longer ICU lengths of stay than other groups: acute care emergency surgery (13.5 ± 17.4 d) versus general surgery (8.7 ± 12.9), transplant (7.8 ± 11.6), oral-maxillofacial surgery (5.5 ± 4.2), and neurosurgery (4.47 ± 9.8) (all p< 0.01). Ventilator usage, defined by percentage of total ICU days patients required mechanical ventilation, was significantly higher for acute care emergency surgery patients: acute care emergency surgery 73.4% versus general surgery 64.9%, transplant 63.3%, oral-maxillofacial surgery 58.4%, and neurosurgery 53.1% (all p < 0.01). Continuous renal replacement therapy usage, defined as percent of patients requiring this service, was significantly higher in acute care emergency surgery patients: acute care emergency surgery 10.8% versus general surgery 4.3%, transplant 6.6%, oral-maxillofacial surgery 0%, and neurosurgery 0.5% (all p < 0.01). Acute care emergency surgery patients were more likely interhospital transfers for tertiary care services than general surgery or transplant (24.5% vs 15.5% and 8.3% respectively, p < 0.001 for each) and more likely required emergent surgery (13.7% vs 6.7% and 3.5%, all p < 0.001). Chronic comorbidities were similar between acute care emergency surgery and general surgery, whereas transplant had fewer. Conclusions:Emergency general surgery patients have increased ICU needs in terms of length of stay, ventilator usage, and continuous renal replacement therapy usage compared with other services, perhaps due to the higher percentage of transfers and emergent surgery required. These patients represent a distinct population. Understanding their resource needs will allow for better deployment of hospital resources.

Acute Care Surgery: Defining the Economic Burden of Emergency General Surgery

BACKGROUND Trauma centers (TCs) have been shown to provide lifesaving, but more expensive, care when compared with non-TCs (NTC). Limited data exist about the economic impact of emergency general surgery (EGS) patients on health care systems. We hypothesized that the economic burden would be higher for EGS patients managed at TCs vs NTCs. METHODS The Maryland Health Services Cost Review Commission database was queried from 2009 to 2013. The American Association for the Surgery of Trauma EGS ICD-9 codes were used to define the top 10 EGS diagnoses. Demographic characteristics, TC designation, severity of illness, and hospital charge data were collected. Differences in total charges between TCs and NTCs were analyzed by Wilcoxon test using SAS 9.3 software (SAS Institute). RESULTS A total of 435,623 patients were included. Median age was 61 years (interquartile range 47 to 76 years) and 55.9% were female. Median length of stay was 4 days; 90.3% were admitted via emergency department; and overall mortality was 5.1%. Overall median charges were

Acute Care Surgery: Defining Mortality in Emergency General Surgery in the State of Maryland

11,081 for TC vs

Management and outcomes of blunt common and external iliac arterial injuries

8,264 for NTC (p < 0.0001). Minor, moderate, major, and extreme severities of illness all had higher charges at TC vs NTC with no ICU admissions, respectfully (

Determination of efficacy of a novel alginate dressing in a lethal arterial injury model in swine

5,908 vs