Validation of a miniaturized handheld arterial pressure monitor for guiding full and partial REBOA use during resuscitation.

PURPOSE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a well-validated method for the control of noncompressible truncal hemorrhage. In lower resource or battlefield settings, the need for arterial line setup and monitoring is problematic and potentially prohibitive. We sought to evaluate the accuracy and precision of a miniaturized portable device (Centurion COMPASS®) versus standard arterial pressure monitoring using standard ER-REBOA and partial REBOA (pREBOA) as a high-fidelity and space-/time-conserving alternative. METHODS: A total of 40 swine underwent a four-phase validation/precision study (each phase using five ER-REBOAs and five pREBOAs). Phases I/II evaluated accuracy with full and pREBOA in uninjured animals. Phases III/IV duplicated the previous phases but in a severe hemorrhagic shock model. Carotid and femoral pressures were monitored with both intra-arterial pressure systems and the COMPASS® device. The vascular flow was measured by aortic flow probes. Correlation and Bland-Altman analysis were performed. RESULTS: There was a strong correlation in accuracy testing of proximal and distal COMPASS® devices compared to standard intra-arterial pressure monitoring (r = 0.94, 0.8; p < 0.005) as well as during precision testing (r = 0.98, 0.89 p < 0.005) in the uninjured phases. Similar accuracy and reliability were demonstrated in hemorrhagic shock, with a strong correlation for the proximal and distal COMPASS® devices (r = 0.98, 0.97; p < 0.005), as well as during precision testing (r = 0.99, 0.95; p < 0.005) in both full and pREBOA scenarios. Bland-Altman analysis showed extremely low bias between the COMPASS® and arterial line for both proximal (bias = 1.9) and distal (bias = 0.8) pressure measurements. CONCLUSION: The COMPASS® provides accurate and precise pressure measurements during standard and partial REBOA in both uninjured and shock conditions. This device may help extend and enhance capability in any low-resource/battlefield settings, or even eliminate the need for standard intra-arterial invasive pressure monitoring and external setup.

Telementorship in Underway Naval Operations: Leveraging Operational Virtual Health for Tactical Combat Casualty Care.

BACKGROUND: Virtual health (VH) may enhance mentorship to remote first responders. We evaluated the feasibility of synchronous bidirectional VH to mentor life-saving procedures performed by deployed novice providers. METHODS: Video teleconferencing (VTC) was established between the USNS Mercy (T-AH 19) underway in the Pacific Ocean to Naval Medical Center San Diego using surgeon teleconsultation. The adult simulated clinical vignette included injuries following a shipboard explosion with subsequent fire. The pediatric simulated vignette included injuries that resulted from an improvised explosive device (IED) blast. Using VTC, augmented reality (AR) goggles, and airway simulation equipment, corpsmen (HMs) received visual cues to perform advanced life-saving procedures. RESULTS: In adult scenarios, 100% of novice hospital HMs performed tasks on first attempt (n = 12). Mean time for tourniquet placement was 46 seconds (standard deviation [SD], 19 seconds); needle thoracostomy, 70 seconds (SD, 67 seconds); tube thoracostomy, 313 seconds (SD, 152 seconds); and cricothyroidotomy, 274 seconds (SD, 82 seconds). In pediatric scenarios, 100% of novice HMs performed tasks on first attempt (n = 5). Mean time for tube thoracostomy completion was 532 seconds (SD, 109 seconds). CONCLUSION: VH can enhance the training and delivery of trauma care during prolonged field care in resource-limited settings.

A tale of two centers: Is low-molecular-weight heparin really superior for prevention of posttraumatic venous thromboembolism?

BACKGROUND: Low-molecular-weight heparin (LMWH) is widely used for venous thromboembolism chemoprophylaxis following injury. However, unfractionated heparin (UFH) is a less expensive option. We compared LMWH and UFH for prevention of posttraumatic deep venous thrombosis (DVT) and pulmonary embolism (PE). METHODS: Trauma patients 15 years or older with at least one administration of venous thromboembolism chemoprophylaxis at two level I trauma centers with similar DVT-screening protocols were identified. Center 1 administered UFH every 8 hours for chemoprophylaxis, and center 2 used twice-daily antifactor Xa-adjusted LMWH. Clinical characteristics and primary chemoprophylaxis agent were evaluated in a two-level logistic regression model. Primary outcome was incidence of DVT and PE. RESULTS: There were 3,654 patients: 1,155 at center 1 and 2,499 at center 2. The unadjusted DVT rate at center 1 was lower than at center 2 (3.5% vs. 5.0%; p = 0.04); PE rates did not significantly differ (0.4% vs. 0.6%; p = 0.64). Patients at center 2 were older (mean, 50.3 vs. 47.3 years; p < 0.001) and had higher Injury Severity Scores (median, 10 vs. 9; p < 0.001), longer stays in the hospital (mean, 9.4 vs. 7.0 days; p < 0.001) and intensive care unit (mean, 3.0 vs. 1.3 days; p < 0.001), and a higher mortality rate (1.6% vs. 0.6%, p = 0.02) than patients at center 1. Center 1's patients received their first dose of chemoprophylaxis earlier than patients at center 2 (median, 1.0 vs. 1.7 days; p < 0.001). After risk adjustment and accounting for center effects, primary chemoprophylaxis agent was not associated with risk of DVT (odds ratio, 1.01; 95% confidence interval, 0.69-1.48; p = 0.949). Cost calculations showed that UFH was less expensive than LMWH. CONCLUSION: Primary utilization of UFH is not inferior to LMWH for posttraumatic DVT chemoprophylaxis and rates of PE are similar. Given that UFH is lower in cost, the choice of this chemoprophylaxis agent may have major economic implications. LEVEL OF EVIDENCE: Prognostic and epidemiological, level II; Therapeutic, level III.

Is cerebral perfusion maintained during full and partial resuscitative endovascular balloon occlusion of the aorta in hemorrhagic shock conditions?

BACKGROUND: Partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) is a technology that occludes aortic flow and allows for controlled deflation and restoration of varying distal perfusion. Carotid flow rates (CFRs) during partial deflation are unknown. Our aim was to measure CFR with the different pREBOA balloon volumes and correlate those to the proximal mean arterial pressure (PMAP) and a handheld pressure monitoring device (COMPASS; Mirador Biomedical, Seattle, WA). METHODS: Ten swine underwent a hemorrhagic injury model with carotid and iliac arterial pressures monitored via arterial lines. Carotid and aortic flow rates were monitored with Doppler flow probes. A COMPASS was placed to monitor proximal pressure. The pREBOA was inflated for 15 minutes then partially deflated for an aortic flow rate of 0.7 L/min for 45 minutes. It was then completely deflated. Proximal mean arterial pressures and CFR were measured, and correlation was evaluated. Correlation between CRF and COMPASS measurements was evaluated. RESULTS: Carotid flow rate increased 240% with full inflation. Carotid flow rate was maintained at 100% to 150% of baseline across a wide range of partial deflation. After full deflation, CFR transiently decreased to 45% to 95% of baseline. There was strong positive correlation (r > 0.85) between CFR and PMAP after full inflation, and positive correlation with partial inflation (r > 0.7). Carotid flow rate had strong correlation with the COMPASS with full REBOA (r > 0.85) and positive correlation with pREBOA (r > 0.65). CONCLUSION: Carotid flow rate is increased in a hemorrhagic model during full and partial inflation of the pREBOA and correlates well with PMAP. Carotid perfusion appears maintained across a wide range of pREBOA deflation and could be readily monitored with a handheld portable COMPASS device instead of a standard arterial line setup.

Real-time bedside management and titration of partial resuscitative endovascular balloon occlusion of the aorta without an arterial line: Good for pressure, not for flow!

BACKGROUND: Partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) attempts to minimize ischemia/reperfusion injury while controlling hemorrhage. There are little data on optimal methods to evaluate and titrate partial flow, which typically requires invasive arterial line monitoring. We sought to examine the use of a miniaturized handheld digital pressure device (COMPASS; Mirador Biomedical, Seattle, WA) for pREBOA placement and titration of flow. METHODS: Ten swine underwent standardized hemorrhagic shock. Carotid and iliac pressures were monitored with both arterial line and COMPASS devices, and flow was monitored by aortic and superior mesenteric artery flow probes. Partial resuscitative endovascular balloon occlusion of the aorta was inflated to control hemorrhage for 15 minutes before being deflated to try targeting aortic flow of 0.7 L/min (using only the COMPASS device) by an operator blinded to the arterial line pressures and aortic flow. Correlations between COMPASS and proximal/distal arterial line were evaluated, as well as actual aortic flow. RESULTS: There was strong correlation between the distal mean arterial pressure (MAP) and the distal COMPASS MAP (r = 0.979, p < 0.01), as well as between the proximal arterial line and the proximal COMPASS on the pREBOA (r = 0.989, p < 0.01). There was a significant but weaker correlation between the distal compass MAP reading and aortic flow (r = 0.47, p < 0.0001), although it was not clinically significant and predicted flow was not achieved in a majority of the procedures. Of 10 pigs, survival times ranged from 10 to 120 minutes, with a mean survival of 50 minutes, and 1 pig surviving to 120 minutes. CONCLUSION: Highly reliable pressure monitoring is achieved proximally and distally without arterial lines using the COMPASS device on the pREBOA. Despite accurate readings, distal MAPs were a poor indicator of aortic flow, and titration based upon distal MAPs did not provide reliable results. Further investigation will be required to find a suitable proxy for targeting specific aortic flow levels using pREBOA.

Association of Operative Repair Type and Trauma Center Designation With Outcomes in Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: Open repair of ruptured abdominal aortic aneurysm (rAAA) has shown improved outcomes at trauma centers. Whether the benefit of trauma center designation extends to endovascular repair of rAAA is unknown. METHODS: Retrospective cohort study using the California Office of Statewide Health Planning and Development 2007 to 2014 discharge database to identify patients with rAAA. Data included demographic and admission factors, discharge disposition, International Classification of Diseases, Ninth Revision, Clinical Modification codes, and hospital characteristics. Hospitals were categorized by trauma center designation and teaching hospital status. The effect of repair type and trauma center designation (level I, level II, or other-other trauma centers and nondesignated hospitals) was evaluated to determine rates and risks of 9 postoperative complications, in-hospital mortality, and 30-day postdischarge mortality. RESULTS: Of 1941 rAAA repair patients, 61.2% had open and 37.8% had endovascular; 1.0% had both. Endovascular repair increased over the study interval. Hospitals were 12.0% level I, 25.0% level II, and 63.0% other. A total of 48.7% of hospitals were teaching hospitals (level I, 100%; level II, 42.2%; and other, 41.8%). Endovascular repair was significantly more common at teaching hospitals (41.5% vs 34.3%, P < .001) and was the primary repair method at level I trauma centers (P < .001). Compared with open repair, endovascular repair was protective for most complications and in-hospital mortality. The risk for in-hospital mortality was highest among endovascular patients at level II trauma centers (hazard ratio 1.67, 95% confidence interval [CI]: 0.95-2.92) and other hospitals (hazard ratio 1.66, 95% CI: 1.01-2.72). CONCLUSIONS: Endovascular repair overall was associated with a lower risk of adverse outcomes. Endovascular repair at level I trauma centers had a lower risk of in-hospital mortality which may be a result of their teaching hospital status, organizational structure, and other factors. The weight of the contributions of such factors warrants further study.

Quetiapine therapy in critically injured trauma patients is associated with an increased risk of pulmonary complications.

BACKGROUND: The aim of this study was to evaluate quetiapine-associated pulmonary complications (PC) in critically injured trauma patients. METHODS: Injured adults admitted during 2016 to the ICU at a Level I trauma center were analyzed. Outcomes were evaluated by competing risks survival analysis. RESULTS: Of 254 admissions, 40 (15.7%) had PC and 214 (84.3%) were non-events. PC patients were more severely injured, had longer hospital stays and were more likely to die. Patients administered quetiapine were more likely to develop PC and acquire PC earlier than those without quetiapine. Quetiapine was a positive risk factor for PC (sHR 2.24, p = 0.013). Stratification by ventilator use revealed non-ventilated patients administered quetiapine had the highest risk for PC (sHR 4.66, p = 0.099). CONCLUSIONS: Quetiapine exposure in critically injured trauma patients was associated with increased risk of PC. Guidelines for treatment of delirium with quetiapine in critically injured trauma patients should account for this risk.

Association of complicated gallstone disease in pregnancy and adverse birth outcomes.

BACKGROUND: Complicated gallstone disease (CGD) is a common condition requiring intervention during pregnancy to avert adverse birth outcomes (ABO). METHODS: Cohort study using the California OSHPD 2007-2014 database. Records of pregnant patients were analyzed for gallbladder calculus within four months of delivery. Biliary system interventions were evaluated as the primary exposure. RESULTS: Of 7,597 patients, those with CGD had a greater likelihood of biliary system procedures than those with uncomplicated gallstone disease (36.6% vs. 2.5%, p < 0.001). Patients with CGD also had increased odds of ABO (OR 2.02, 95% CI, 1.48-2.76). Compared to patients without biliary system procedures, those with interventions for gallstones had an OR of 3.46 (95% CI, 2.48-4.82) for ABO. After adjustment, biliary system intervention for CGD had an even greater risk of ABO (OR 4.26, 95% CI, 2.86-6.35). CONCLUSIONS: The risk of ABO is significantly increased in women with CGD and intervention for gallstones.

Pediatric extremity vascular trauma: It matters where it is treated.

BACKGROUND: Extremity vascular injuries in children are rare events that present unique therapeutic challenges. The absence of a pediatric-specific protocol for definitive care of these injuries risks variability in treatment practices and outcomes. Using a nationwide data set, we investigated variations in the management and outcomes of pediatric patients with peripheral vascular trauma and characterized differences based on hospital category. METHODS: Retrospective cohort study using the American College of Surgeons (ACS) National Trauma Data Bank to identify patients 16 years or younger with extremity vascular trauma admitted in calendar year 2016. Hospitals were categorized as ACS-verified pediatric trauma centers (Level I or II), ACS-verified adult trauma centers (Level I or II), or other hospitals (all other trauma centers and nondesignated hospitals). Patient data were evaluated by hospital category. RESULTS: Among 164,882 pediatric admissions, 702 patients were identified for analysis. There were 430 (61.3%) patients with upper-extremity injuries, 270 (38.5%) with lower-extremity injuries, and 2 (0.2%) had both. Mean age was 11.5 years, and 51.6% were blunt-injured. Overall, 40.2% were admitted to pediatric trauma centers, 28.9% to adult trauma centers, and 30.9% to other hospitals. Hospitals without ACS trauma center verification had a significantly higher amputation rate than any ACS-verified adult or pediatric center (p = 0.013). CONCLUSION: The incidence of pediatric extremity vascular injury is low. Hospitals with ACS trauma center verification have greater pediatric limb salvage rates than those without verification. Future study should seek to identify specific regional or resource-related factors that contribute to this disparity. LEVEL OF EVIDENCE: Epidemiological, level III.

Evaluating surgical outcomes in pediatric extremity vascular trauma.

BACKGROUND: The purpose of this study was to evaluate the epidemiology and management of pediatric vascular extremity trauma to assess injury patterns and other factors that may contribute to poor outcomes. METHODS: Using the California Office of Statewide Health Planning and Development discharge database, we identified pediatric patients with extremity arterial trauma admitted to acute-care hospitals from 2007 to 2014. Demographics, management patterns, and outcomes were collected and analyzed. RESULTS: A total of 775 patients were treated for an extremity arterial injury. Overall, 40% were admitted to pediatric trauma centers and 39% to adult trauma centers. Management was predominantly by open surgical repair. Injury to the common femoral artery was associated with mortality (Hazard Ratio 3.9; 95% CI 1.1-14.5; p < 0.05). Popliteal artery injuries (Odds Ratio [OR] 4.8; 95% CI 1.2-19.9; p < 0.05) and anterior tibial artery injuries (OR 7.1; 95% CI 1.4-37.3; p < 0.05) had an increased risk of amputation. There was no difference in amputation or mortality rates by hospital category. CONCLUSIONS: Pediatric extremity arterial injuries are rare. In California, outcomes are similar by hospital type. Common femoral artery injuries are associated with an increased risk of mortality, while popliteal and anterior tibial artery injuries are associated with an increased risk of amputation. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: Level III.

Outcomes in adhesive small bowel obstruction from a large statewide database: What to expect after nonoperative management.

BACKGROUND: Although adhesive small-bowel obstruction (ASBO) is frequently managed nonoperatively, little is known regarding outcomes on readmission following this approach. Using a large population-based dataset, we evaluated risk factors for operative intervention and mortality at readmission in patients with ASBO who were initially managed nonoperatively. METHODS: The ASBO patients were identified in the California Office of Statewide Health Planning and Development 2007 to 2014 patient discharge database. Patients who were managed operatively at index admission or had an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code for nonadhesive obstructive small bowel disease were excluded. Associations between risk factors and both operative intervention and death following readmission were evaluated using survival analysis. RESULTS: Among 15,963 ASBO patients, 3,103 (19.4%) had at least one readmission. The 1,069 (34.5%) who received an operation during their first readmission presented sooner (175 days vs. 316 days, p < 0.001) and were more likely to die during that readmission (5.2% vs. 0.7%, p < 0.001). Operative management at first readmission was associated with younger age, fewer comorbidities, and shorter times to readmission. Patients operatively managed at first readmission had longer times to second readmission compared with nonoperative patients. Stratified analyses using nonoperative patients as the reference over the study period revealed that patients who underwent lysis of adhesions and bowel resection were 5.04 times (95% confidence interval [CI], 2.82-9.00) as likely to die while those who underwent lysis only were 2.09 times (95% CI, 1.14-3.85) as likely to die. Patients with bowel resection only were at an increased risk for subsequent interventions beyond the first readmission (hazard ratio, 1.79; 95% CI, 1.11-2.87). CONCLUSION: In a large cohort readmitted for ASBO and initially managed nonoperatively, subsequent operative intervention conferred a greater risk of death and a longer time to readmission among survivors. Prospective research is needed to further delineate outcomes associated with initial nonoperative management of ASBO. LEVEL OF EVIDENCE: Prognostic and epidemiological, level III.

Radiofrequency Identification of the ER-REBOA: Confirmation of Placement Without Fluoroscopy.

INTRODUCTION: Non-compressible torso hemorrhage accounts for 70% of battlefield deaths. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technology used to mitigate massive truncal hemorrhage. Use of REBOA on the battlefield is limited by the need for radiographic guided balloon placement. Radiofrequency identification (RFID) is a simple, portable, real-time technology utilized to detect retained sponges during surgery. We investigated the feasibility of RFID to confirm the placement of ER-REBOA. MATERIALS AND METHODS: This was a single-arm prospective proof-of-concept experimental study approved by the institutional review board at Naval Medical Center San Diego. The ER-REBOA (Prytime Medical Devices, Inc, Boerne, TX, USA) was modified by placement of a RFID tag. The tagged ER-REBOA was placed in zone I or zone III of the aorta in a previously perfused cadaver. Exact location was documented with X-ray. Five blinded individuals used the RF Assure Detection System (Medtronic, Minneapolis, MN, USA) handheld detection wand to predict catheter tip location from the xiphoid process (zone I) or pubic tubercle (zone III). RESULTS: In zone I, actual distance (Da) of the catheter tip was 11 cm from the xiphoid process. Mean predicted distance (Dp) from Da was 1.52 cm (95% CI 1.19-1.85). In zone III, Da was 14 cm from the pubic tubercle. Mean Dp from Da was 4.11 cm (95% CI 3.68-4.54). Sensitivity of detection was 100% in both zones. Specificity (Defined as Dp within 2 cm of Da) was 86% in zone I and 16% in zone III. CONCLUSIONS: Using RFID to confirm the placement of ER-REBOA is feasible with specificity highest in zone I. Future work should focus on refining this technology for the forward-deployed setting.

Outcomes for popliteal artery injury repair after discharge: A large-scale population-based analysis.

BACKGROUND: Although short-term outcomes for popliteal artery injury after endovascular versus open repair appear similar, studies on outcomes after discharge are limited. We evaluated popliteal artery injury repair in a population-based data set. We hypothesized that postdischarge outcomes for open repair are superior to endovascular repair. METHODS: Patients with popliteal artery injury were identified in the California Office of Statewide Health Planning and Development 2007-2014 discharge database. Popliteal artery injury and other lower-extremity injuries were identified using International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. Procedure codes were evaluated to identify open repair, endovascular repair, fasciotomy, and amputation. Primary outcomes were mortality or amputation. The association between repair method and each outcome was evaluated with logistic regression. Postdischarge amputation and all-cause mortality were evaluated using survival analysis. RESULTS: Among 769 patients with popliteal artery injury, open repair occurred in 456 (59.3%), endovascular repair in 37 (4.3%), combined endovascular and open in 18 (2.3%), and nonoperative management in 258 (33.6%). Fasciotomy was performed more frequently in open than endovascular repair (p = 0.001) during index admission. Amputation rate was also increased in open repair, but this was not significant (p = 0.196). Arterial thromboembolus during index admission was more likely after endovascular or combined endovascular and open compared with open (24.3%, 55.6%, 16.7%, respectively, p < 0.001). Patients requiring both endovascular and open were more likely to undergo amputation postdischarge (hazard ratio, 4.11; 95% confidence interval, 1.16-14.53). Patients undergoing endovascular repair were more likely to die postdischarge (hazard ratio, 4.43; 95% confidence interval, 1.06-18.56) compared with patients who had open repair (median, 98.5 days postdischarge). CONCLUSIONS: In a large cohort with popliteal artery injury, open repair was associated with lower rates of index admission arterial thromboembolus as well as postdischarge amputation and all-cause mortality. We recommend conducting a prospective multicenter study to examine the appropriate use of endovascular repair for this injury. LEVEL OF EVIDENCE: Therapeutic, level IV.

Outcomes after single-look trauma laparotomy: A large population-based study.

BACKGROUND: Outcomes following damage control laparotomy for trauma have been studied in detail. However, outcomes following a single operation, or "single-look trauma laparotomy" (SLTL), have not. We evaluated the association between SLTL and both short-term and long-term outcomes in a large population-based data set. METHODS: The California Office of Statewide Health Planning and Development patient discharge database was evaluated for calendar years 2007 through 2014. Injured patients with SLTL during their index admission were identified using International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes. Diagnosis and procedure codes were used to identify specific abdominal organ injuries, surgical interventions, and perioperative complications. Subsequent acute care admissions were examined for postoperative complications and related surgical interventions. Clinical characteristics, injuries, surgical interventions, and outcomes were analyzed by mechanism of injury. RESULTS: There were 2113 patients with SLTL during their index admission; 712 (33.7%) had at least one readmission to an acute care facility. Median time to first readmission was 110 days. Penetrating mechanism was more common than blunt (60.6% vs. 39.4%). Compared to patients with penetrating injury, blunt-injured patients had a significantly higher median Injury Severity Score (9 vs. 18, p < 0.0001) and a significantly higher mortality rate during the index admission (4.1% vs. 27.0%, p < 0.0001). More than 30% of SLTL patients requiring readmission had a surgery-related complication. The most common primary reasons for readmission were bowel obstruction (17.7%), incisional hernia (11.8%), and infection (9.1%). There was no significant association between mechanism of injury and development of surgery-related complications requiring readmission. CONCLUSIONS: Patients with SLTL had postinjury morbidity and mortality, and more than 30% required readmission. Complication rates for SLTL were comparable to those reported for emergency general surgery procedures. Patients should be educated on signs and symptoms of the most common complications before discharge following SLTL. Further investigation should focus on the factors associated with the development of these complications. LEVEL OF EVIDENCE: Prognostic and epidemiologic study, level III.