Effect of Antibiotic Duration in Emergency General Surgery Patients with Intra-Abdominal Infection Managed with Open vs Closed Abdomen.

BACKGROUND: Data on duration of antibiotics in patients managed with an open abdomen (OA) due to intra-abdominal infection (IAI) are scarce. We hypothesized that patients with IAI managed with OA rather than closed abdomen (CA) would have higher rates of secondary infections (SIs) independent of the duration of the antibiotic treatment. METHODS: This was an observational, prospective, multicenter, international study of patients with IAI requiring laparotomy for source control. Demographic and antibiotic duration values were collected. Primary outcomes were SI (surgical site, bloodstream, pneumonia, urinary tract) and mortality. Statistical analysis included ANOVA, chi-square/Fisher's exact test, and logistic regression. RESULTS: Twenty-one centers contributed 752 patients. The average age was 59.6 years, 43.6% were women, and 43.9% were managed with OA. Overall mortality was 16.1%, with higher rates among OA patients (31.6% vs 4.4%, p < 0.001). OA patients had higher Sequential Organ Failure Assessment (4.7 vs 1.8, p < 0.001), American Society of Anesthesiologists Physical Status (3.6 vs 2.7, p < 0.001), and APACHE II scores (16.1 vs 9.4, p < 0.001). The mean duration of antibiotics was 6.5 days (8.0 OA vs 5.4 CA, p < 0.001). A total of 179 (23.8%) patients developed SI (33.1% OA vs 16.8% CA, p < 0.001). Longer antibiotic duration was associated with increased rates of SI: 1 to 2 days, 15.8%; 3 to 5 days, 20.4%; 6 to 14 days, 26.6%; and more than 14 days, 46.8% (p < 0.001). CONCLUSIONS: Patients with IAI managed with OA had higher rates of SI and increased mortality compared with CA. A prolonged duration of antibiotics was associated with increased rates of SI. Increased antibiotic duration is not associated with improved outcomes in patients with IAI and OA.

Prehospital end-tidal carbon dioxide is predictive of death and massive transfusion in injured patients: An Eastern Association for Surgery of Trauma multicenter trial.

BACKGROUND: Prehospital identification of the injured patient likely to require emergent care remains a challenge. End-tidal carbon dioxide (ETCO2) has been used in the prehospital setting to monitor respiratory physiology and confirmation of endotracheal tube placement. Low levels of ETCO2 have been demonstrated to correlate with injury severity and mortality in a number of in-hospital studies. We hypothesized that prehospital ETCO2 values would be predictive of mortality and need for massive transfusion (MT) in intubated patients. METHODS: This was a retrospective multicenter trial with 24 participating centers. Prehospital, emergency department, and hospital values were collected. Receiver operating characteristic curves were created and compared. Massive transfusion defined as >10 U of blood in 6 hours or death in 6 hours with at least 1 U of blood transfused. RESULTS: A total of 1,324 patients were enrolled. ETCO2 (area under the receiver operating characteristic curve [AUROC], 0.67; confidence interval [CI], 0.63-0.71) was better in predicting mortality than shock index (SI) (AUROC, 0.55; CI, 0.50-0.60) and systolic blood pressure (SBP) (AUROC, 0.58; CI, 0.53-0.62) (p < 0.0005). Prehospital lowest ETCO2 (AUROC, 0.69; CI, 0.64-0.75), SBP (AUROC, 0.75; CI, 0.70-0.81), and SI (AUROC, 0.74; CI, 0.68-0.79) were all predictive of MT. Analysis of patients with normotension demonstrated lowest prehospital ETCO2 (AUROC, 0.66; CI, 0.61-0.71), which was more predictive of mortality than SBP (AUROC, 0.52; CI, 0.47-0.58) or SI (AUROC, 0.56; CI, 0.50-0.62) (p < 0.001). Lowest prehospital ETCO2 (AUROC, 0.75; CI, 0.65-0.84), SBP (AUROC, 0.63; CI, 0.54-0.74), and SI (AUROC, 0.64; CI, 0.54-0.75) were predictive of MT in normotensive patients. ETCO2 cutoff for MT was 26 mm Hg. The positive predictive value was 16.1%, and negative predictive value was high at 98.1%. CONCLUSION: Prehospital ETCO2 is predictive of mortality and MT. ETCO2 outperformed traditional measures such as SBP and SI in the prediction of mortality. ETCO2 may outperform traditional measures in predicting need for transfusion in occult shock. LEVEL OF EVIDENCE: Diagnostic test, level III.

Surgical Simulation: Markers of Proficiency.

OBJECTIVE: Surgical simulation has become an integral component of surgical training. Simulation proficiency determination has been traditionally based upon time to completion of various simulated tasks. We aimed to determine objective markers of proficiency in surgical simulation by comparing novel assessments with conventional evaluations of technical skill. DESIGN: Categorical general surgery residents completed 10 laparoscopic cholecystectomy modules using a high-fidelity simulator. We recorded and analyzed simulation task times, as well as number of hand movements, instrument path length, instrument acceleration, and participant affective engagement during each simulation. Comparisons were made to Objective Structured Assessment of Technical Skill (OSATS) and Accreditation Council for Graduate Medical Education Milestones, as well as previous laparoscopic experience, duration of laparoscopic cholecystectomies performed by participants, and postgraduate year. Comparisons were also made to Fundamentals of Laparoscopic Surgery task times. Spearman's rho was utilized for comparisons, significance set at >0.50. SETTING: University of Missouri, Columbia, Missouri, an academic tertiary care facility. PARTICIPANTS: Fourteen categorical general surgery residents (postgraduate year 1-5) were prospectively enrolled. RESULTS: One hundred forty simulations were included. The number of hand movements and instrument path lengths strongly correlated with simulation task times (ρ 0.62-0.87, p < 0.0001), FLS task completion times (ρ 0.50-0.53, p < 0.0001), and prior real-world laparoscopic cholecystectomy experience (ρ -0.51 to -0.53, p < 0.0001). No significant correlations were identified between any of the studied markers with Accreditation Council for Graduate Medical Education Milestones, Objective Structured Assessment of Technical Skill evaluations, total previous laparoscopic experience, or postgraduate year level. Neither instrument acceleration nor participant engagement showed significant correlation with any of the conventional markers of real-world or simulation skill proficiency. CONCLUSIONS: Simulation proficiency, measured by instrument and hand motion, is more representative of simulation skill than simulation task time, instrument acceleration, or participant engagement.

Case Difficulty, Postgraduate Year, and Resident Surgeon Stress: Effects on Operative Times.

OBJECTIVE: We aimed to evaluate resident operative times in relation to postgraduate year (PGY), case difficulty and resident stress while performing a single surgical procedure. DESIGN: We prospectively examined operative times for 268 laparoscopic cholecystectomies, and analyzed relationships between PGY, case difficulty, and resident surgeon stress utilizing electrodermal activity. Each case operative times were divided into 3 separate time periods. Case Start and End times were recorded, as well as the time between the start of the operation and the time until the cystic structures were divided (Division). Case difficulty was determined by multiple trained observers with a high inter-rater concordance. SETTING: University of Missouri, a tertiary academic medical institution. PARTICIPANTS: All categorical general surgery residents at our institution. RESULTS: For each operative time period examined during laparoscopic cholecystectomy, operative time increased, with each incremental increase in difficulty resulting in approximately 130% longer times. Minimal differences in operative times were seen between PGY levels, except during the easiest cases (Start-End times: 38.5 ± 10.4 minutes vs 34.2 ± 10.8 minutes vs 28.9 ± 10.9 minutes, p 0.002). Resident stress poorly correlated with operative times regardless of case difficulty (Pearson coefficient range 0.0-0.22). CONCLUSIONS: Operative times are longer with increasing case difficulty. PGY level and resident surgeon stress appear to have minimal to no correlation with operative times, regardless of case difficulty.

Clearing the cervical spine in patients with distracting injuries: An AAST multi-institutional trial.

BACKGROUND: Single institution studies have shown that clinical examination of the cervical spine (c-spine) is sensitive for clearance of the c-spine in blunt trauma patients with distracting injuries. Despite an unclear definition, most trauma centers still adhere to the notion that distracting injuries adversely affect the sensitivity of c-spine clinical examination. A prospective AAST multi-institutional trial was performed to assess the sensitivity of clinical examination screening of the c-spine in awake and alert blunt trauma patients with distracting injuries. METHODS: During the 42-month study period, blunt trauma patients 18 years and older were prospectively evaluated with a standard c-spine examination protocol at 8 Level 1 trauma centers. Clinical examination was performed regardless of the presence of distracting injuries. Patients without complaints of neck pain, tenderness or pain on range of motion were considered to have a negative c-spine clinical examination. All patients with positive or negative c-spine clinical examination underwent computed tomography (CT) scan of the entire c-spine. Clinical examination findings were documented prior to the CT scan. RESULTS: During the study period, 2929 patients were entered. At least one distracting injury was diagnosed in 70% of the patients. A c-spine injury was found on CT scan in 7.6% of the patients. There was no difference in the rate of missed injury when comparing patients with a distracting injury to those without a distracting injury (10.4% vs. 12.6%, p = 0.601). Only one injury missed by clinical examination underwent surgical intervention and none had a neurological complication. CONCLUSIONS: Negative clinical examination may be sufficient to clear the cervical spine in awake and alert blunt trauma patients, even in the presence of a distracting injury. These findings suggest a potential source for improvement in resource utilization. LEVEL OF EVIDENCE: Therapeutic/care management, level IV.

Temporal expression of circulating miRNA after severe injury.

BACKGROUND: Severe injury can lead to immune dysfunction and predispose patients to infection and death. Micro-RNAs regulate gene expression and may act as biomarkers for susceptibility to infection. The aim of this study was to examine the temporal and differential expression of previously identified dysregulated micro-RNAs in patients with severe injury. METHODS: Fourteen severely injured patients requiring transfusion were enrolled prospectively in this study approved by our institutional review board. Inclusion criteria consisted of adult patients deemed clinically to be in hemorrhagic shock necessitating transfusion in the acute phase of their injury care. Peripheral blood samples were obtained after admission to the surgical intensive care unit and again at 6, 12, 24, and 48 hours after admission. The samples obtained at arrival to the intensive care unit and 24 and 48 hours later were analyzed in this data set. Fourteen healthy volunteers served as controls. The 10 dysregulated micro-RNAs identified in a prior study at the 12-hour time point and important genes in innate immunity were measured using quantitative reverse transcription-polymerase chain reaction. RESULTS: The participants were 21-77 years old (median, 42), 78% were male, and their Injury Severity Score ranged from 11 to 43 (median, 27); 11 had blunt and 3 had penetrating injuries. Three were intubated and 5 had received blood products before arrival at the hospital. Base deficit on hospital admission was 3-20 (median, 9). All patients required blood transfusion secondary to blood loss sustained during injury. Eleven of the 14 patients went directly to the operating room from the emergency department for control of the source of hemorrhage. Survival to discharge was 93%. Seven patients developed infection. Compared with healthy controls, miR-106a was downregulated at all time points compared with controls (P < .05). miR-618 was upregulated in initial blood draws (P < .05) and at 24 and 48 hours (P < .06). Tumor necrosis factor α and human leukocyte antigen-DR (HLA-DR) were downregulated, and interleukin-10 and PD-L1 were upregulated (P < .05). In patients who developed infection, miR-106a levels appeared more downregulated than those who did not develop infection. CONCLUSION: miR-106a was downregulated in trauma patients after major injury for up to 48 hours after intensive care unit admission. Tumor necrosis factor α and interleukin-10 are targeted by miR-106a, which are regulators of the immune response. Manipulation of micro-RNA expression may be a therapeutic target for immune dysfunction.

Perceptions of Simulator- and Live Tissue-Based Combat Casualty Care Training of Senior Special Operations Medics.

The relative effectiveness of live tissue (LT)- and inanimate simulation (SIM)-based training of combat medics is the subject of intense debate. A structured interview was utilized to determine the training modality preferences and the perceived value of LT- and SIM-based combat casualty care training of 25 senior special operations medics. Participant demographics and training experience, Likert scale-based assessment of training modality value, selection of preferred training modality for 11 combat casualty care procedures, and 12 open-ended questions probing opinions of the limitations and benefits of LT- and SIM-based training were collected from this convenience sample. All participants indicated significant combat medic experience and training. Of the 11 procedures questioned, LT was identified as superior for seven with mixed responses for the remaining four. LT was consistently identified as an essential training modality with tactile sensation and the physiologic responses of animal models to injury and therapy as primary benefits. Across procedures, 100% of participants felt that LT should be used in combat casualty care training and 96% felt that SIM should also be utilized. Repeatability and accuracy of size/weight were identified as key benefits of SIM training. Respondents reported that capability, self-confidence, success, and resilience of the combat medic all benefitted from LT training. The overriding theme was the general superiority of LT with recognition of the unique and complementary benefits of SIM.

Pulmonary Contusion in Mechanically Ventilated Subjects After Severe Trauma.

BACKGROUND: Pulmonary contusions are thought to worsen outcomes. We aimed to evaluate the effects of pulmonary contusion on mechanically ventilated trauma subjects with severe thoracic injuries and hypothesized that contusion would not increase morbidity. METHODS: We conducted a single-center, retrospective review of 163 severely injured trauma subjects (injury severity score ≥ 15) with severe thoracic injury (chest abbreviated injury score ≥ 3), who required mechanical ventilation for >24 h at a verified Level 1 trauma center. Subject data were analyzed for those with radiographic documentation of pulmonary contusion and those without. Statistical analysis was performed to determine the effects of coexisting pulmonary contusion in severe thoracic trauma. RESULTS: Pulmonary contusion was present in 91 subjects (55.8%), whereas 72 (44.2%) did not have pulmonary contusions. Mean chest abbreviated injury score (3.54 vs 3.47, P = .53) and mean injury severity score (32.6 vs 30.2, P = .12) were similar. There was no difference in mortality (11 [12.1%] vs 9 [12.5%], P > .99) or length of stay (16.29 d vs 17.29 d, P = .60). Frequency of ventilator-associated pneumonia was comparable (43 [47.3%] vs 32 [44.4%], P = .75). Subjects with contusions were more likely to grow methicillin-sensitive Staphylococcus aureus in culture (33 vs 10, P = .004) as opposed to Pseudomonas aeruginosa in culture (6 vs 13, P = .003). CONCLUSIONS: Overall, no significant differences were noted in mortality, length of stay, or pneumonia rates between severely injured trauma subjects with and without pulmonary contusions.

Inadequacy of Algorithmic Ventilator-Associated Pneumonia Diagnosis in Acute Care Surgery.

Clinical utility of algorithms to diagnose ventilator-associated pneumonia (VAP) in surgical patients has not been established. We aimed to test the diagnostic accuracy of two established methods to reliably diagnose VAP in acutely ill and injured surgical patients. After institutional review board approval, we prospectively collected data on 508 mechanically ventilated acute care surgery patients. Microbiologic samples were taken daily from all patients. Demographics, clinical, laboratory, and radiographic data were collected. The Johanson Criteria (JC) and Clinical Pulmonary Infection Score (CPIS) were calculated and analyzed. Sensitivity, specificity, and positive predictive values (PPV) and negative predictive value (NPV) were calculated in comparison to positive respiratory cultures. Of the 508 patients, 312 (61.4%) were acutely injured; emergent general surgery was performed in 141 (27.8%) patients, and 54 (10.6%) underwent elective operation. Positive respiratory cultures were identified in 198 (39%) of the 508 patients. JC diagnosed VAP in 291 (57.3%) patients (sensitivity 82.8%, specificity 59%, PPV 56.4%, NPV 84.3%, accuracy 68.3%). The CPIS resulted in 189 (37.2%) VAP diagnoses (sensitivity 61.1%, specificity 78.1%, PPV 64%, NPV 75.9%, and accuracy 71.5%). To address the inaccuracy of the algorithms, concordance testing was performed on the data to evaluate correlation between the algorithmic VAP diagnosis criteria and respiratory culture data. Nonconcordance with culture data diagnosis was identified with both JC (rho 0.41) and CPIS (rho 0.41). Sensitivity, specificity, PPV and NPV, and accuracy of both established clinical formulas was unacceptably low in acute care surgery patients.

Surgical resident technical skill self-evaluation: increased precision with training progression.

BACKGROUND: Surgical resident ability to accurately evaluate one's own skill level is an important part of educational growth. We aimed to determine if differences exist between self and observer technical skill evaluation of surgical residents performing a single procedure. MATERIALS AND METHODS: We prospectively enrolled 14 categorical general surgery residents (six post-graduate year [PGY] 1-2, three PGY 3, and five PGY 4-5). Over a 6-month period, following each laparoscopic cholecystectomy, residents and seven faculty each completed the Objective Structured Assessment of Technical Skills (OSATS). Spearman's coefficient was calculated for three groups: senior (PGY 4-5), PGY3, and junior (PGY 1-2). Rho (ρ) values greater than 0.8 were considered well correlated. RESULTS: Of the 125 paired assessments (resident-faculty each evaluating the same case), 58 were completed for senior residents, 54 for PGY3 residents, and 13 for junior residents. Using the mean from all OSATS categories, trainee self-evaluations correlated well to faculty (senior ρ 0.97, PGY3 ρ 0.9, junior ρ 0.9). When specific OSATS categories were analyzed, junior residents exhibited poor correlation in categories of respect for tissue (ρ -0.5), instrument handling (ρ 0.71), operative flow (ρ 0.41), use of assistants (ρ 0.05), procedural knowledge (ρ 0.32), and overall comfort with the procedure (ρ 0.73). PGY3 residents lacked correlation in two OSATS categories, operative flow (ρ 0.7) and procedural knowledge (ρ 0.2). Senior resident self-evaluations exhibited strong correlations to observers in all areas. CONCLUSIONS: Surgical residents improve technical skill self-awareness with progressive training. Less-experienced trainees have a tendency to over-or-underestimate technical skill.

Objective Measurement of Clinical Competency in Surgical Education Using Electrodermal Activity.

OBJECTIVE: Within the realm of surgical education, there is a need for objective means to determine surgical competence and resident readiness to operate independently. We propose a novel, objective method of assessing resident confidence and clinical competence based on measurement of electrodermal activity (EDA) during live surgical procedures. We hypothesized that with progressive training, EDA responses to the stress of performing surgery would exhibit decline, elucidating an objective correlate of clinical competence. DESIGN: EDA was measured using galvanic skin response sensors worn by residents performing laparoscopic cholecystectomy on sequential live human patients over an 8-month period. Baseline, phasic (peak) and tonic EDA responses were measured as a fractional change from baseline. SETTING: University of Missouri, Columbia, Missouri, an academic tertiary care facility. PARTICIPANTS: Fourteen categorical general surgery residents and 5 faculty surgeons were voluntarily enrolled and participated through completion. RESULTS: Tonic fractional change (FCTONIC) was highest in PGY3 residents compared with postgraduate year (PGY) 1 and 2 residents (7.199 vs. 2.100, p = 0.004, 95% CI: 8.58-1.61 and PGY4 and 5 residents (7.199 vs. 2.079, p = 0.002, 95% CI: 8.38-0.29). Phasic fractional change in EDA (FCPHASIC) exhibited a progressive decline across resident training levels, with PGY1 and 2 residents having the highest response, and faculty displaying the lowest FCPHASIC responses. Statistical differences were seen between FCPHASIC faculty and PGY4 and 5 (3.596 vs. 6.180, p = 0.004, 95% CI: 0.80-4.36), PGY4 and 5, and PGY3 (6.180 vs. 15.998, p = 0.003, 95% CI: 3.33-16.3), as well as among all residents and faculty (13.057 vs. 3.596, p = 0.004, 95% CI: 15.8-3.1). CONCLUSION: Phasic EDA changes decrease with increasing clinical competence. For those participants with the lowest and highest levels of competence, tonic EDA changes are minimal. Tonic EDA changes follow an inverse-U shape with differing levels of clinical competence.

Platelet adenosine diphosphate inhibition in trauma patients by thromboelastography correlates with paradoxical increase in platelet dense granule content by flow cytometry.

BACKGROUND: The mechanism of platelet dysfunction in acute traumatic coagulopathy is unknown. Traumatic brain injury is hypothesized as a cause, while some investigators presume platelets become "exhausted." We hypothesized that platelet hyperstimulation and consumption resulting from trauma leads to decreased platelet function secondary to depletion of platelet granules. METHODS: Twenty-five trauma patients were divided into traumatic brain injury and no traumatic brain injury groups. Healthy volunteers served as controls. All had thromboelastography with platelet mapping and flow cytometric assays of mepacrine performed. Mepacrine uptake in unstimulated platelets was used for quantification of platelet content of dense granules. RESULTS: Twelve patients with traumatic brain injury and 13 patients without traumatic brain injury were enrolled. Twenty-one trauma patients showed adenosine diphosphate inhibition (>30%) on thromboelastography with platelet mapping compared with the healthy volunteers who served as controls (P < .01). Mepacrine assay showed a difference in mean fluorescent intensity for all trauma patients of 4,259 ± 1,341 compared with controls of 3,143 ± 709 (P = .044), correlating with greater quantities of dense granules. Neither adenosine diphosphate inhibition nor average difference in mean fluorescent intensity between traumatic brain injury and no traumatic brain injury groups were significant (P = .2). CONCLUSION: Trauma patients maintain their dense granule, contradicting the theory of platelet granule exhaustion as the etiology for platelet dysfunction in traumatic brain injury.

Live tissue versus simulation training for emergency procedures: Is simulation ready to replace live tissue?

BACKGROUND: Training of emergency procedures is challenging and application is not routine in all health care settings. The debate over simulation as an alternative to live tissue training continues with legislation before Congress to banish live tissue training in the Department of Defense. Little evidence exists to objectify best practice. We sought to evaluate live tissue and simulation-based training practices in 12 life-saving emergency procedures. METHODS: In the study, 742 subjects were randomized to live tissue or simulation-training. Assessments of self-efficacy, cognitive knowledge, and psychomotor performance were completed pre- and post-training. Affective response to training was assessed through electrodermal activity. Subject matter experts gap analysis of live tissue versus simulation completed the data set. RESULTS: Subjects demonstrated pre- to post-training gains in self-efficacy, cognitive knowledge, psychomotor performance, and affective response regardless of training modality (P < .01 each). With the exception of fluid resuscitation in the psychomotor performance domain, no statistically significant differences were observed based on training modality in the overall group. Risk estimates on the least pretest performance subgroup favored simulation in 7 procedures. Affective response was greatest in live tissue training (P < .01) and varied by species and model. Subject matter experts noted significant value in live tissue in 7 procedures. Gap analysis noted shortcomings in all models and synergy between models. CONCLUSION: Although simulation has made significant gains, no single modality can be identified definitively as superior. Wholesale abandonment of live tissue training is not warranted. We maintain that combined live tissue and simulation-based training add value and should be continued. Congressional mandates may accelerate simulation development and improve performance.

The Negative Impact of Anemia in Outcome from Traumatic Brain Injury.

BACKGROUND: Whether anemia complicating traumatic brain injury (TBI) has an impact on patient outcomes is controversial; therefore, recommendations for blood transfusions for such patients are inconsistent. We hypothesized that patient outcome after TBI would be worse in patients with lower hemoglobin levels. METHODS: We retrospectively reviewed records of patients with TBI and head Abbreviated Injury Scale >3 with abnormal head computed tomography findings and neurologic injury. The relationships between initial hemoglobin and lowest hemoglobin during hospitalization at threshold values of ≤7, ≤8, ≤9, and ≤10 g/dL were investigated relative to Glasgow Outcome Score at last follow-up not exceeding 1 year. RESULTS: Of 939 patients meeting inclusion criteria, initial and lowest hemoglobin concentrations were significant predictors of poor outcome (P < 0.0001). For each 1 g/dL higher hemoglobin value, the likelihood of a good outcome increased by 33%. More severe levels of initial anemia were associated with lower Glasgow Coma Scale, greater head Abbreviated Injury Scale, and greater Injury Severity Score (P < 0.0001). Female patients had worse outcome than male patients only for initial hemoglobin between 7 and 8 g/dL (P < 0.05). Blood transfusion was associated with poorer outcome at hemoglobin levels ≤9 and ≤10 g/dL (P < 0.05), but not at lower hemoglobin thresholds. CONCLUSIONS: Patient outcome after TBI is worse in patients with lower hemoglobin. Initial hemoglobin and lowest hemoglobin after admission are independently associated with poor outcome. Our data support consideration of blood transfusion when hemoglobin is ≤8 g/dl.

In-flight ultrasound identification of pneumothorax.

Ultrasound is a standard adjunct to the initial evaluation of injured patients in the emergency department. We sought to evaluate the ability of prehospital, in-flight thoracic ultrasound to identify pneumothorax. Non-physician aeromedical providers were trained to perform and interpret thoracic ultrasound. All adult trauma patients and adult medical patients requiring endotracheal intubation underwent both in-flight and emergency department ultrasound evaluations. Findings were documented independently and reviewed to ensure quality and accuracy. Results were compared to chest X-ray and computed tomography (CT). One hundred forty-nine patients (136 trauma/13 medical) met inclusion criteria. Mean age was 44.4 (18-94) years; 69 % were male. Mean injury severity score was 17.68 (1-75), and mean chest injury score was 2.93 (0-6) in the injured group. Twenty pneumothoraces and one mainstem intubation were identified. Sixteen pneumothoraces were correctly identified in the field. A mainstem intubation was misinterpreted. When compared to chest CT (n = 116), prehospital ultrasound had a sensitivity of 68 % (95 % confidence interval (CI) 46-85 %), a specificity of 96 % (95 % CI 90-98 %), and an overall accuracy of 91 % (95 % CI 85-95 %). In comparison, emergency department (ED) ultrasound had a sensitivity of 84 % (95 % CI 62-94 %), specificity of 98 % (95 % CI 93-99 %), and an accuracy of 96 % (95 % CI 90-98 %). The unique characteristics of the aeromedical environment render the auditory element of a reliable physical exam impractical. Thoracic ultrasonography should be utilized to augment the diagnostic capabilities of prehospital aeromedical providers.

Failure of the Platelet Function Assay (PFA)-100 to detect antiplatelet agents.

BACKGROUND: Antiplatelet therapy is a complicating factor in patients with traumatic brain injuries (TBI), as well as those with hemorrhagic cerebrovascular accidents (CVAs). Platelet Function Assay (PFA)-100 is a coagulation device that can detect platelet dysfunction caused by aspirin and adenosine diphosphate inhibition. Our retrospective study reviewed the effectiveness of PFA-100 in detecting platelet dysfunction caused by aspirin and clopidogrel and determined its clinical importance. METHODS: All patients with PFA-100 tests from January 2013 to February 2014 were collected. Diagnoses indicative of a TBI or CVA were chosen for analysis. Patients with a normal PFA-100 indicating no platelet dysfunction but with documented aspirin and/or clopidogrel use were selected. An extensive chart review was performed to determine the relevance to their clinical care. RESULTS: A total of 475 patients were evaluated with a PFA-100 from January 2013 to February 2014. PFA-100 detected platelet dysfunction as the result of pre-injury use of antiplatelet agents in TBI and CVA patients with a sensitivity of only 48.6% and a specificity of 74.8%. Had these antiplatelet medications been known during initial workup, these patients would have had a change in management that may have impacted their outcomes. CONCLUSION: Despite its common usage, the PFA-100 is an unreliable tool to assist in the management of TBI and CVA patients. Additional investigation into alternative methods for detecting platelet dysfunction is warranted.

Less Is More: Low-dose Prothrombin Complex Concentrate Effective in Acute Care Surgery Patients.

Optimal dosing of prothrombin complex concentrate (PCC) has yet to be defined and varies widely due to concerns of efficacy and thrombosis. We hypothesized a dose of 15 IU/kg actual body weight of a three-factor PCC would effectively correct coagulopathy in acute care surgery patients. Retrospective review of 41 acute care surgery patients who received 15 IU/kg (± 10%) actual body weight PCC for correction of coagulopathy. Demographics, laboratory results, PCC dose, blood and plasma transfusions, and thrombotic complications were analyzed. We performed subset analyses of trauma patients and those taking warfarin. Mean age was 69 years (18-94 years). Thirty (73%) trauma patients, 8 (20%) emergency surgery patients, 2 (5%) burns, and 1 (2%) nontrauma neurosurgical patient were included. Mean PCC dose was 1305.4 IU (14.2 IU/kg actual body weight). Mean change in INR was 2.52 to 1.42 (p 0.00004). Successful correction (INR <1.5) was seen in 78 per cent. Treatment failures had a higher initial INR (4.3 vs 2.03, p 0.01). Mean plasma transfusion was 1.46 units. Mean blood transfusion was 1.61 units. Patients taking prehospital warfarin (n = 29, 71%) had higher initial INR (2.78 vs 1.92, p 0.05) and received more units of plasma (1.93 vs 0.33, p 0.01) than those not taking warfarin. No statistical differences were seen between trauma and nontrauma patients. One thrombotic event occurred. Administration of low-dose PCC, 15 IU/kg actual body weight, effectively corrects coagulopathy in acute care surgery patients regardless of warfarin use, diagnosis or plasma transfusion.