Acute proximal superior mesenteric artery (SMA) occlusion is highly lethal, and adjuncts are needed to mitigate ischemic injury until definitive therapy. We hypothesized that raising mean arterial ...pressure (MAP) >90 mmHg with norepinephrine may delay irreversible bowel ischemia by increasing gastroduodenal artery (GDA) flow despite possible pressor-induced vasospasm.
12 anesthetized swine underwent laparotomy, GDA flow probe placement, and proximal SMA exposure and clamping. Animals were randomized between conventional therapy (CT) versus targeted MAP >90 mmHg (MAP push; MP) where norepinephrine was titrated after 45 min of SMA occlusion. Animals were followed until bowel death or 4 h. Kaplan-Meier bowel survival, mean normalized GDA flow, and histology were compared.
12 swine (mean 57.8 ± 7.6 kgs) were included, six per group. Baseline weight, HR, MAP and GDA flows were not different. Within 5 min following SMA clamping, all 12 animals had an increase in MAP without other intervention from 81.7 to 105.5 mmHg (29.1%, P < 0.01) with a concomitant 74.9% increase in GDA flow as compared to baseline (P < 0.01). Beyond 45 min postclamp, MAP was greater in the MP group as intended, as were GDA flows. Median time to irreversibly ischemic bowel was 31% longer for MAP push animals (CT: 178 versus MP: 233 min, P = 0.006), Hazard Ratio of CT 8.85 (95% CI: 1.86-42.06); 3/6 MP animals versus 0/6 CT animals with bowel survived to predetermined end point.
In this swine model of acute complete proximal SMA occlusion, increasing MAP >90 mmHg with norepinephrine was associated with an increase in macrovascular blood flow through the GDA and bowel survival. Norepinephrine was not associated with worse bowel survival and a MAP push may increase the time window where ischemic bowel can be salvaged.
Massive transfusion (MT) in pediatric patients remains poorly defined. Using the largest existing registry of transfused pediatric trauma patients, we sought a data-driven MT threshold.
The ...Department of Defense Trauma Registry was queried from 2001 to 2013 for pediatric trauma patients (<18 years). Burns, drowning, isolated head injury, and missing Injury Severity Score (ISS) were excluded. MT was evaluated as a weight-based volume of all blood products transfused in the first 24 hours. Mortality at 24 hours and in the hospital was calculated for increasing transfusion volumes. Sensitivity and specificity curves for predicting mortality were used to identify an optimal MT threshold. Patients above and below this threshold (MT+ and MT-, respectively) were compared.
The Department of Defense Trauma Registry yielded 4,990 combat-injured pediatric trauma patients, of whom 1,113 were transfused and constituted the study cohort. Sensitivity and specificity for 24-hour and in-hospital mortality were optimal at 40.1-mL/kg and 38.6-mL/kg total blood products in the first 24 hours, respectively. With the use of a pragmatic threshold of 40 mL/kg, patients were divided into MT+ (n = 443) and MT- (n = 670). MT+ patients were more often in shock (68.1% vs. 47.0%, p < 0.001), hypothermic (13.0% vs. 3.4%, p < 0.001), coagulopathic (45.0% vs. 29.6%, p < 0.001), and thrombocytopenic (10.6% vs. 5.0%, p = 0.002) on presentation. MT+ patients had a higher ISS, more mechanical ventilator days, and longer intensive care unit and hospital stay. MT+ was independently associated with an increased 24-hour mortality (odds ratio, 2.50; 95% confidence interval, 1.28-4.88; p = 0.007) and in-hospital mortality (odds ratio, 2.58; 95% confidence interval, 1.70-3.92; p < 0.001).
Based on this large cohort of transfused combat-injured pediatric patients, a threshold of 40 mL/kg of all blood products given at any time in the first 24 hours reliably identifies critically injured children at high risk for early and in-hospital death. This evidence-based definition will provide a consistent framework for future research and protocol development in pediatric resuscitation.
Diagnostic study, level II. Prognostic/epidemiologic study, level III.
Partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) is a potential method to mitigate the ischemia observed in full REBOA (fREBOA). However, the effect of pREBOA on cerebral ...perfusion in the setting of raised intracranial pressure (rICP) is unknown. The aim was to evaluate the effects of no REBOA (nREBOA) vs pREBOA vs fREBOA on cerebral perfusion in a swine model of rICP and hemorrhagic shock.
Anesthetized swine (n = 18) underwent instrumentation. Controlled hemorrhage was performed over 30 minutes. rICP was achieved using an intracranial Fogarty catheter inflated to achieve an ICP of 20 mmHg. Animals underwent intervention for 30 minutes, followed by resuscitation. The primary outcome was cerebral perfusion measured by ICP (millimeters of mercury), cerebral perfusion pressure (CPP; millimeters of mercury), and cerebral blood flow (CBF; milliliters per minute per 100 g) derived from CT perfusion. The secondary outcomes included hemodynamics and lactate (millimoles per liter).
The peak ICP of pREBOA animals (22.7 ± 2.5) was significantly lower than nREBOA and fREBOA. pREBOA CPP was significantly higher compared with nREBOA and fREBOA during resuscitation. The pREBOA CBF was greater during intervention and resuscitation compared with nREBOA (p < 0.001). Systolic blood pressure was similar between pREBOA and fREBOA, and coronary perfusion was significantly greater in pREBOA. fREBOA had significantly higher lactate during the intervention (9.3 ± 1.3) and resuscitation (8.9 ± 3.5) compared with nREBOA and pREBOA.
pREBOA produced greater cerebral perfusion, as demonstrated by more favorable CPP, CBF, and ICP values. fREBOA was associated with metabolic derangement and diminished pressure during resuscitation. pREBOA is superior to fREBOA in a swine model and should be considered over fREBOA for aortic occlusion.
Incidence and treatment of blunt thoracic aortic injury (BTAI) has evolved, likely from improved imaging and emergence of endovascular techniques; however, multicenter data demonstrating this are ...lacking. We examined trends in incidence, management, and outcomes in BTAI.
The American College of Surgeons National Trauma Databank (2003 to 2013) was used to identify adults with BTAI. Management was categorized as nonoperative repair, open aortic repair (OAR), or thoracic endovascular repair (TEVAR). Outcomes included demographics, management, and outcomes.
There were 3,774 patients. Median age was 46.0 years (interquartile range IQR 29.3, 62.0 years), with 70.8% males, and median Injury Severity Score (ISS) of 34.0 (IQR 26.0, 45.0). The number of BTAIs diagnosed over the decade increased 196.8% (p < 0.001), median ISS decreased from 38 to 33 (p < 0.001), and significantly more patients were treated at a level I trauma center (p < 0.001). After FDA approval of TEVAR devices, there was a significant increase in endovascular repair overall (1.0% to 30.6%, p < 0.001) and in those treated operatively (0.0% to 94.9%, p < 0.001), with a marked decrease in OAR. Use of TEVAR was associated with significantly reduced median ICU LOS (9.0 vs 12.0 days, p = 0.048) and mortality (9.3% vs 16.6%; p = 0.015) compared with OAR. In modern BTAI care, TEVAR has nearly completely replaced OAR.
The diagnosis of BTAI has increased, likely due to more sensitive imaging. Nearly 70% of patients get nonoperative care. Treatment with TEVAR improves outcomes relative to OAR. Part of the proportional increase in TEVAR use may represent overtreatment of lower grade BTAI amenable to medical management, and warrants further investigation.
Tracheal trauma is uncommon but carries major morbidity and mortality. A 26-year-old man sustained a near-transection of the cervical trachea due to penetrating trauma. Venovenous extracorporeal ...membrane oxygenation support allowed a controlled primary repair with muscular buttress and facilitated airway management. Facial injuries prevented oral intubation, and retrograde intubation through the transection established an airway. On the 10th postoperative day a percutaneous tracheostomy was performed through the surgical site. This case discusses the management, technical details, and adjuncts to successfully repair complex tracheal injuries.
A theory is presented where the weakly nonlinear analysis of laminar globally unstable flows in the presence of external forcing is extended to the turbulent regime. The analysis is demonstrated and ...validated using experimental results of an axisymmetric bluff-body wake at high Reynolds numbers,
$Re_{D}\sim 1.88\times 10^{5}$
, where forcing is applied using a zero-net-mass-flux actuator located at the base of the blunt body. In this study we focus on the response of antisymmetric coherent structures with azimuthal wavenumbers
$m=\pm 1$
at a frequency
$St_{D}=0.2$
, responsible for global vortex shedding. We found experimentally that axisymmetric forcing (
$m=0$
) couples nonlinearly with the global shedding mode when the flow is forced at twice the shedding frequency, resulting in parametric subharmonic resonance through a triadic interaction between forcing and shedding. We derive simple weakly nonlinear models from the phase-averaged Navier–Stokes equations and show that they capture accurately the observed behaviour for this type of forcing. The unknown model coefficients are obtained experimentally by producing harmonic transients. This approach should be applicable in a variety of turbulent flows to describe the response of global modes to forcing.
Bleeding is the most common cause of preventable death after trauma.
To determine the effectiveness of resuscitative endovascular balloon occlusion of the aorta (REBOA) when used in the emergency ...department along with standard care vs standard care alone on mortality in trauma patients with exsanguinating hemorrhage.
Pragmatic, bayesian, randomized clinical trial conducted at 16 major trauma centers in the UK. Patients aged 16 years or older with exsanguinating hemorrhage were enrolled between October 2017 and March 2022 and followed up for 90 days.
Patients were randomly assigned (1:1 allocation) to a strategy that included REBOA and standard care (n = 46) or standard care alone (n = 44).
The primary outcome was all-cause mortality at 90 days. Ten secondary outcomes included mortality at 6 months, while in the hospital, and within 24 hours, 6 hours, or 3 hours; the need for definitive hemorrhage control procedures; time to commencement of definitive hemorrhage control procedures; complications; length of stay; blood product use; and cause of death.
Of the 90 patients (median age, 41 years IQR, 31-59 years; 62 69% were male; and the median Injury Severity Score was 41 IQR, 29-50) randomized, 89 were included in the primary outcome analysis because 1 patient in the standard care alone group declined to provide consent for continued participation and data collection 4 days after enrollment. At 90 days, 25 of 46 patients (54%) had experienced all-cause mortality in the REBOA and standard care group vs 18 of 43 patients (42%) in the standard care alone group (odds ratio OR, 1.58 95% credible interval, 0.72-3.52; posterior probability of an OR >1 indicating increased odds of death with REBOA, 86.9%). Among the 10 secondary outcomes, the ORs for mortality and the posterior probabilities of an OR greater than 1 for 6-month, in-hospital, and 24-, 6-, or 3-hour mortality were all increased in the REBOA and standard care group, and the ORs were increased with earlier mortality end points. There were more deaths due to bleeding in the REBOA and standard care group (8 of 25 patients 32%) than in standard care alone group (3 of 18 patients 17%), and most occurred within 24 hours.
In trauma patients with exsanguinating hemorrhage, a strategy of REBOA and standard care in the emergency department does not reduce, and may increase, mortality compared with standard care alone.
isrctn.org Identifier: ISRCTN16184981.
Abstract Background The objective of this study was to evaluate the efficacy of resuscitative endovascular aortic balloon occlusion (REBOA) of the distal aorta in a porcine model of pelvic ...hemorrhage. Methods Swine were entered into three phases of study: injury (iliac artery), hemorrhage (45 s), and intervention (180 min). Three groups were studied: no intervention (NI, n = 7), a kaolin-impregnated gauze (Combat Gauze) (CG, n = 7), or REBOA ( n = 7). The protocol was repeated with a dilutional coagulopathy (CG-C, n = 7, and REBOA-C, n = 7). Measures of physiology, rates of hemorrhage, and mortality were recorded. Results Rate of hemorrhage was greatest in the NI group, followed by the REBOA and CG groups (822 ± 415 mL/min versus 11 ± 13 and 0.2 ± 0.4 mL/min respectively; P < 0.001). MAP following intervention (at 15 min) was the same in the CG and REBOA groups and higher than in the NI group (70 ± 4 and 70 ± 11 mm Hg versus 5 ± 13 mm Hg respectively; P < 0.001). There was 100% mortality in the NI group, with no deaths in the CG or REBOA group. In the setting of coagulopathy, the rate of bleeding was higher in the CG-C versus the REBOA-C group (229 ± 295 mL/min versus 20 ± 7 mL/min, P = 0.085). MAP following intervention (15 min) was higher in the REBOA-C than the CG-C group (71 ± 12 mm Hg versus 28 ± 31 mm Hg; P = 0.005). There were 5 deaths (71.4%) in the CG-C group, but none in the REBOA-C group ( P = 0.010). Conclusion Balloon occlusion of the aorta is an effective method to control pelvic arterial hemorrhage. This technique should be further developed as an adjunct to manage noncompressible pelvic hemorrhage.
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