Abstract

BACKGROUND Tactical Combat Casualty Care (TCCC) is the standard of care for stabilization and treatment of military trauma patients. The DoD has mandated that all Service members receive role-based TCCC training and certification. Simulation education can increase procedural skills by providing opportunities for deliberate practice in safe, controlled environments. We developed and evaluated the effectiveness of a simulation-based TCCC training intervention to improve participants' skill performance and self-confidence in tourniquet placement. METHODS This study was a single-blinded, randomized trial with waitlist controls. Army ROTC cadets from a single training battalion comprised the study population. After randomization and baseline assessment of all participants, Group A alone received focused, simulation-based TCCC tourniquet application training. Three months later, all participants underwent repeat testing, and after crossover, the waitlist Group B received the same intervention. Two months later, all cadets underwent a third/final assessment. The primary outcome was tourniquet placement proficiency assessed by total score achieved on a standardized 8-item skill checklist. A secondary outcome was self-confidence in tourniquet application skill as judged by participants' Likert scale ratings. RESULTS Forty-three Army ROTC cadets completed the study protocol. Participants in both Group A (n = 25) and Group B (n = 18) demonstrated significantly higher performance from baseline to final assessment at five months and two months, respectively, following the intervention. Mean total checklist score of the entire study cohort increased significantly from 5.53 (SD = 2.00) at baseline to 7.56 (SD = 1.08) at Time 3, a gain of 36.7% (p < 0.001). Both groups rated their self-confidence in tourniquet placement significantly higher following the training. CONCLUSIONS A simulation-based TCCC curriculum resulted in significant, consistent, and sustained improvement in participants' skill proficiency and self-confidence in tourniquet placement. Participants maintained these gains two to five months after initial training. LEVEL OF EVIDENCE Level II - RCT with significant difference and only one negative criterion (<80% follow-up).

Abstract

IMPORTANCE Gamma irradiation of leukoreduced red blood cells (RBCs) prevents transfusion-associated graft-vs-host disease but also exacerbates storage lesion formation in RBCs. It is unknown whether freshly irradiated RBCs are more efficacious than irradiated and stored RBCs in preterm infants with high transfusion requirements. OBJECTIVE To examine whether transfusion of freshly irradiated vs irradiated and stored RBC components improves cerebral oxygen delivery in preterm infants with anemia. DESIGN, SETTING, AND PARTICIPANTS This single-center, double-blinded, proof-of-concept randomized clinical trial was conducted at the neonatal intensive care unit of Wellington Regional Hospital in Wellington, New Zealand, between December 1, 2017, and November 30, 2018. Participants were preterm infants (<34 weeks' gestation at birth) who were at least 14 days of age and had anemia. Participants underwent nonurgent transfusions, and these episodes were randomized to the intervention group (in which the infants received a transfusion of RBCs that were freshly irradiated on the day of transfusion) or control group (in which the infants received a transfusion of RBCs that were irradiated and stored for up to 14 days). Data were analyzed using the evaluable population approach. INTERVENTION Transfusion of freshly irradiated RBCs. MAIN OUTCOMES AND MEASURES The prespecified primary outcome was the change in cerebral regional oxygen saturation (crSO2) from baseline (immediately before) to immediately after the transfusion. The prespecified secondary outcomes were the change in cerebral fractional tissue oxygen extraction (cFTOE) at different time points (immediately after, 24 hours after, and 120 hours or 5 days after transfusion). Outcomes were measured by blinded clinicians using near-infrared spectroscopy. A covariate-adjusted linear mixed model was used to quantify mean treatment effects and account for multiple transfusions in some infants. RESULTS A total of 42 infants (mean [SD] gestational age, 26 [10] weeks and 3 days; 29 [69%] boys) were enrolled in the trial and underwent 64 transfusion episodes, which were randomized to the intervention (n = 31) or control (n = 33) group. Compared with infants in the control group, those in the intervention group showed a covariate-adjusted mean increase in crSO2 (2.0 percentage points; 95% CI, 1.2-2.8 percentage points) and a mean decrease in cFTOE (0.02; 95% CI, 0.01-0.04) immediately after transfusion. These differences were sustained up to 120 hours or 5 days after transfusion. There were negligible mean changes in crSO2 or cFTOE in infants in the control group at any of the follow-up time points. CONCLUSIONS AND RELEVANCE Results of this trial showed that transfusion of freshly irradiated RBCs conferred a small advantage in cerebral oxygenation for at least 5 days after transfusion compared with transfusion of irradiated and stored RBC components. On-demand irradiation of RBC components may be considered to optimize oxygen delivery in the recipient, but this physiological finding requires further research. TRIAL REGISTRATION ANZCTR Identifier: ACTRN12617001581358.

Abstract

BACKGROUND We aimed to develop and validate a new nomogram for predicting the risk of intracranial hemorrhage (ICH) in patients with acute ischemic stroke (AIS) after intravenous thrombolysis (IVT). METHODS A retrospective study enrolled 553 patients with AIS treated with IVT. The patients were randomly divided into two cohorts: the training set (70%, n = 387) and the testing set (30%, n = 166). The factors in the predictive nomogram were filtered using multivariable logistic regression analysis. The performance of the nomogram was assessed based on the area under the receiver operating characteristic curve (AUC-ROC), calibration plots, and decision curve analysis (DCA). RESULTS After multivariable logistic regression analysis, certain factors, such as smoking, National Institutes of Health of Stroke Scale (NIHSS) score, blood urea nitrogen-to-creatinine ratio (BUN/Cr), and neutrophil-to-lymphocyte ratio (NLR), were found to be independent predictors of ICH and were used to construct a nomogram. The AUC-ROC values of the nomogram were 0.887 (95% CI: 0.842-0.933) and 0.776 (95% CI: 0.681-0.872) in the training and testing sets, respectively. The AUC-ROC of the nomogram was higher than that of the Multicenter Stroke Survey (MSS), Glucose, Race, Age, Sex, Systolic blood Pressure, and Severity of stroke (GRASPS), and stroke prognostication using age and NIH Stroke Scale-100 positive index (SPAN-100) scores for predicting ICH in both the training and testing sets (p < 0.05). The calibration plot demonstrated good agreement in both the training and testing sets. DCA indicated that the nomogram was clinically useful. CONCLUSIONS The new nomogram, which included smoking, NIHSS, BUN/Cr, and NLR as variables, had the potential for predicting the risk of ICH in patients with AIS after IVT.

Abstract

Balanced crystalloids may improve outcomes compared to saline for some critically ill adults. Lower tonicity of balanced crystalloids could worsen cerebral edema in patients with intracranial pathology. The effect of balanced crystalloids versus saline on clinical outcomes in patients with traumatic brain injury (TBI) requires further study. We planned an a priori subgroup analysis of TBI patients enrolled in the pragmatic, cluster-randomized, multiple-crossover Isotonic Solutions and Major Adverse Renal Events Trial (SMART) (ClinicalTrials.gov: NCT02444988, NCT02547779). Primary outcome was 30-day in-hospital mortality. Secondary outcomes included hospital discharge disposition (home, facility, death). Regression models adjusted for pre-specified baseline covariates compared outcomes. TBI patients assigned to balanced crystalloids (n=588) and saline (n=569) had similar baseline characteristics including Injury Severity Score 19 (10); mean maximum head/neck Abbreviated Injury Score, 3.4 (1.0). Isotonic crystalloid volume administered between ICU admission and first of hospital discharge or 30 days was 2037 (3470) mL and 1723 (2923) mL in the balanced crystalloids and saline groups, respectively (P=0.18). During the study period, 94 (16%) and 82 (14%) patients (16%) died in the balanced crystalloid and saline groups, respectively (aOR, 1.03; 95% confidence interval [CI], 0.60 to 1.75; P=0.913). Patients in the balanced crystalloid group were more likely to die or be discharged to another medical facility (aOR 1.38 [1.02-1.86]; P=0.04). Overall, balanced crystalloids were associated with worse discharge disposition in critically injured patients with TBI compared to saline. The confidence intervals cannot exclude a clinically relevant increase in mortality when balanced crystalloids are used for patients with TBI.

Abstract

IMPORTANCE Hyperintense foci on diffusion-weighted imaging (DWI) that are spatially remote from the acute hematoma occur in 20% of people with acute spontaneous intracerebral hemorrhage (ICH). Tranexamic acid, a hemostatic agent that is under investigation for treating acute ICH, might increase DWI hyperintense lesions (DWIHLs). OBJECTIVE To establish whether tranexamic acid compared with placebo increased the prevalence or number of remote cerebral DWIHLs within 2 weeks of ICH onset. DESIGN, SETTING, AND PARTICIPANTS This prospective nested magnetic resonance imaging (MRI) substudy of a randomized clinical trial (RCT) recruited participants from the multicenter, double-blind, placebo-controlled, phase 3 RCT (Tranexamic Acid for Hyperacute Primary Intracerebral Hemorrhage [TICH-2]) from July 1, 2015, to September 30, 2017, and conducted follow-up to 90 days after participants were randomized to either the tranexamic acid or placebo group. Participants had acute spontaneous ICH and included TICH-2 participants who provided consent to undergo additional MRI scans for the MRI substudy and those who had clinical MRI data that were compatible with the brain MRI protocol of the substudy. Data analyses were performed on an intention-to-treat basis on January 20, 2020. INTERVENTIONS The tranexamic acid group received 1 g in 100-mL intravenous bolus loading dose, followed by 1 g in 250-mL infusion within 8 hours of ICH onset. The placebo group received 0.9% saline within 8 hours of ICH onset. Brain MRI scans, including DWI, were performed within 2 weeks. MAIN OUTCOMES AND MEASURES Prevalence and number of remote DWIHLs were compared between the treatment groups using binary logistic regression adjusted for baseline covariates. RESULTS A total of 219 participants (mean [SD] age, 65.1 [13.8] years; 126 men [57.5%]) who had brain MRI data were included. Of these participants, 96 (43.8%) were randomized to receive tranexamic acid and 123 (56.2%) were randomized to receive placebo. No baseline differences in demographic characteristics and clinical or imaging features were found between the groups. There was no increase for the tranexamic acid group compared with the placebo group in DWIHL prevalence (20 of 96 [20.8%] vs 28 of 123 [22.8%]; odds ratio [OR], 0.71; 95% CI, 0.33-1.53; P = .39) or mean (SD) number of DWIHLs (1.75 [1.45] vs 1.81 [1.71]; mean difference [MD], -0.08; 95% CI, -0.36 to 0.20; P = .59). In an exploratory analysis, participants who were randomized within 3 hours of ICH onset or those with chronic infarcts appeared less likely to have DWIHLs if they received tranexamic acid. Participants with probable cerebral amyloid angiopathy appeared more likely to have DWIHLs if they received tranexamic acid. CONCLUSIONS AND RELEVANCE This substudy of an RCT found no evidence of increased prevalence or number of remote DWIHLs after tranexamic acid treatment in acute ICH. These findings provide reassurance for ongoing and future trials that tranexamic acid for acute ICH is unlikely to induce cerebral ischemic events. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN93732214.

Abstract

BACKGROUND Discordance with well-known sepsis resuscitation guidelines is often attributed to rational assessments of patients at the point of care. Conversely, we sought to explore the impact of choice architecture (i.e., the environment, manner, and behavioral psychology within which options are presented and decisions are made) on decisions to prescribe guideline-discordant fluid volumes. DESIGN We conducted an electronic, survey-based study using a septic shock clinical vignette. Physicians from multiple specialties and training levels at an academic tertiary-care hospital and academic safety-net hospital were randomized to distinct answer sets: control (6 fluid options), time constraint (6 fluid options with a 10-s limit to answer), or choice overload (25 fluid options). The primary outcome was discordance with Surviving Sepsis Campaign fluid resuscitation guidelines. We also measured response times and examined the relationship between each choice architecture intervention group, response time, and guideline discordance. RESULTS A total of 189 of 624 (30.3%) physicians completed the survey. Time spent answering the vignette was reduced in time constraint (9.5 s, interquartile range [IQR] 7.3 s to 10.0 s, P < 0.001) and increased in choice overload (56.8 s, IQR 35.9 s to 86.7 s, P < 0.001) groups compared with control (28.3 s, IQR 20.0 s to 44.6 s). In contrast, the relative risk of guideline discordance was higher in time constraint (2.07, 1.33 to 3.23, P = 0.001) and lower in choice overload (0.75, 0.60, to 0.95, P =0.02) groups. After controlling for time spent reading the vignette, the overall odds of choosing guideline-discordant fluid volumes were reduced for every additional second spent answering the vignette (OR 0.98, 0.97, to 0.99, P < 0.001). CONCLUSIONS Choice architecture may affect fluid resuscitation decisions in sepsis regardless of patient conditions, warranting further investigation in real-world contexts. These effects should be considered when implementing practice guidelines. HIGHLIGHTS Time constrained clinical decision making was associated with increased proportion of guideline-discordant responses and relative risk of failure to prescribe guideline-recommended intravenous fluids using a sepsis clinical vignette.Choice overload increased response times and was associated with decreased proportion of guideline-discordant responses and relative risk of guideline discordance.Physician odds of choosing to prescribe guideline-discordant fluid volumes were reduced with increased deliberation as measured by response times.Clinicians, researchers, policy makers, and administrators should consider the effect of choice architecture on clinical decision making and guideline discordance when implementing guidelines for sepsis and other acute care conditions.

Abstract

BACKGROUND To highlight the heterogeneity of acute temporal blood pressure (BP) changes in the ATACH-2 trial (Antihypertensive Treatment of Acute Cerebral Hemorrhage-2) and associations with the outcomes of intracerebral hemorrhage. METHODS One thousand patients with acute intracerebral hemorrhage, who had been randomized to intensive (110-139 mm Hg) or standard (140-179 mm Hg) systolic BP (SBP) lowering with intravenous nicardipine in ATACH-2 from 2011 to 2015, were analyzed about temporal changes in hourly maximum SBP up to 24 hours after randomization using group-based trajectory modeling. Outcomes included death or disability (modified Rankin Scale score 4-6) at 3 months, neurological deterioration within 24 hours (≥2-point decrease in Glasgow Coma Scale score or ≥4-point increase in National Institutes of Health Stroke Scale score), and acute kidney injury (≥0.3 mg/dL within 48 hours or ≥1.5-fold increase in serum creatinine) within 7 days after onset. RESULTS Group-based trajectory modeling revealed 4 SBP trajectory groups: moderate SBP (from ≈190 mm Hg at hospital arrival to 150-160 mm Hg after randomization; n=298), moderate-to-low SBP (from ≈190 mm Hg to <140 mm Hg; n=395), high-to-low SBP (from >210 mm Hg to <140 mm Hg; n=134), and high SBP (from >210 mm Hg to 160-170 mm Hg; n=173). Patients with intensive treatment accounted for 11.1%, 88.6%, 85.1%, and 1.7% of each group, respectively. Compared with the moderate-to-low SBP group, the high-to-low SBP group showed increased risks of death or disability at 3 months (adjusted odds ratio, 2.29 [95% CI, 1.24-4.26]) and acute kidney injury (adjusted odds ratio, 3.50 [95% CI, 1.83-6.69]), while no increase in neurological deterioration was seen in this group (adjusted odds ratio, 0.48 [95% CI, 0.20-1.13]). The moderate SBP and high SBP groups showed no significant risk differences for such outcomes. CONCLUSIONS Data-driven observation using a group-based trajectory modeling approach may be useful to clarify the relationship between antihypertensive treatment, temporal SBP changes, and outcomes in acute intracerebral hemorrhage. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT01176565.

Abstract

BACKGROUND Resistance breathing amplifies the respiratory pump during inspiration, so may be an effective intervention for treatment of hemorrhagic injuries. In animal studies of actual hemorrhage, and human studies of simulated hemorrhage, resistance breathing protects arterial pressure, and improves tolerance to this stress. Anecdotally, resistance breathing also increases the coupling between sympathetic nerve activity and arterial pressure. The impact of resistance breathing on overall sympathetic nerve activity, however, has not been examined. We tested the hypothesis that resistance breathing increases sympathetic nerve activity during simulated hemorrhage in healthy humans. METHODS Lower body negative pressure (LBNP) was used to simulate hemorrhage in five human subjects (3M, 2F; 29.2 ± 6.8 y). Two experiments were conducted (randomized order): 1) a control condition in which LBNP was applied at 3 mmHg/min until the onset of presyncope, and 2) a resistance breathing condition in which the same LBNP protocol was used, but subjects breathed through a resistance device (set at -7 cm.H2O) during the final stages of the protocol. Arterial pressure and muscle sympathetic nerve activity (MSNA) of the radial nerve were monitored continuously. Bursts frequency (bursts/min) and burst incidence (burst/ 100 heart beats) were used to quantify MSNA. Coupling between diastolic arterial pressure (DAP) and MSNA was assessed by transfer function analysis coherence within the low frequency range (0.04-0.15 Hz). Two-way repeated measures ANOVAs were conducted for assessment of responses in the control and resistance breathing conditions, between baseline and at matched time points late in the LBNP protocol. RESULTS While LBNP induced increases in both MSNA burst frequency (P=0.003) and burst incidence (P=0.06), there was no effect of resistance breathing on MSNA for either index during LBNP (control, 57.9 ± 25.9 bursts/min vs. resistance breathing, 50.6 ± 21.7 bursts/min, P=0.99; control, 55.6 ± 25.6 b/100 heart beats vs. resistance breathing, 42.3 ± 18.3 b/100 heart beats, P=0.42). Additionally, there was no effect of resistance breathing on DAP (control, 73.2 ± 9.9 mmHg vs. resistance breathing, 72.8 ± 4.4 mmHg; P=0.99), or coherence between MSNA and DAP during LBNP (control, 0.53 ± 0.21 vs. resistance breathing, 0.69 ± 0.17; P=0.46). CONCLUSION Contrary to our hypothesis, resistance breathing had no effect on sympathetic nerve activity during LBNP. A limitation of this study is the low sample size (N=5), and high variability of MSNA. Future investigations with a larger sample size are needed to determine if respiratory dynamics can influence the coupling between MSNA and arterial pressure.

Abstract

BACKGROUND Recently, a randomized controlled trial (RCT) demonstrated rapid but individually variable hemodynamic improvement with therapeutic plasma exchange (TPE) in patients with septic shock. Prediction of clinical efficacy in specific sepsis treatments is fundamental for individualized sepsis therapy. METHODS In the original RCT, patients with septic shock of < 24 h duration and norepinephrine (NE) requirement ≥ 0.4 μg/kg/min received standard of care (SOC) or SOC + one single TPE. Here, we report all clinical and biological endpoints of this study. Multivariate mixed-effects modeling of NE reduction was performed to investigate characteristics that could be associated with clinical response to TPE. RESULTS A continuous effect of TPE on the reduction in NE doses over the initial 24 h was observed (SOC group: estimated NE dose reduction of 0.005 µg/kg/min per hour; TPE group: 0.018 µg/kg/min per hour, p = 0.004). Similarly, under TPE, serum lactate levels, continuously decreased over the initial 24 h in the TPE group, whereas lactate levels increased under SOC (p = 0.001). A reduction in biomarkers and disease mediators (such as PCT (p = 0.037), vWF:Ag (p < 0.001), Angpt-2 (p = 0.009), sTie-2 (p = 0.005)) along with a repletion of exhausted protective factors (such as AT-III (p = 0.026), Protein C (p = 0.012), ADAMTS-13 (p = 0.008)) could be observed in the TPE but not in the SOC group. In a multivariate mixed effects model, increasing baseline lactate levels led to greater NE dose reduction effects with TPE as opposed to SOC (p = 0.004). CONCLUSIONS Adjunctive TPE is associated with the removal of injurious mediators and repletion of consumed protective factors altogether leading to preserved hemodynamic stabilization in refractory septic shock. We identified that baseline lactate concentration as a potential response predictor might guide future designing of large RCTs that will further evaluate TPE with regard to hard endpoints. Trial registration Retrospectively registered 18th January 2020 at clinicaltrials.gov (Identifier: NCT04231994 ).

Abstract

BACKGROUND The TRACT trial established the timing of transfusion in children with uncomplicated anaemia (haemoglobin 4-6 g/dL) and the optimal volume (20 vs 30 mL/kg whole blood or 10 vs 15 mL/kg red cell concentrates) for transfusion in children admitted to hospital with severe anaemia (haemoglobin <6 g/dL) on day 28 mortality (primary endpoint). Because data on the safety of blood components are scarce, we conducted a secondary analysis to examine the safety and efficacy of different pack types (whole blood vs red cell concentrates) on clinical outcomes. METHODS This study is a secondary analysis of the TRACT trial data restricted to those who received an immediate transfusion (using whole blood or red cell concentrates). TRACT was an open-label, multicentre, factorial, randomised trial conducted in three hospitals in Uganda (Soroti, Mbale, and Mulago) and one hospital in Malawi (Blantyre). The trial enrolled children aged between 2 months and 12 years admitted to hospital with severe anaemia (haemoglobin <6 g/dL). The pack type used (supplied by blood banks) was based only on availability at the time. The outcomes were haemoglobin recovery at 8 h and 180 days, requirement for retransfusion, length of hospital stay, changes in heart and respiratory rates until day 180, and the main clinical endpoints (mortality until day 28 and day 180, and readmission until day 180), measured using multivariate regression models. FINDINGS Between Sept 17, 2014, and May 15, 2017, 3199 children with severe anaemia were enrolled into the TRACT trial. 3188 children were considered in our secondary analysis. The median age was 37 months (IQR 18-64). Whole blood was the first pack provided for 1632 (41%) of 3992 transfusions. Haemoglobin recovery at 8 h was significantly lower in those who received packed cells or settled cells than those who received whole blood, with a mean of 1·4 g/dL (95% CI -1·6 to -1·1) in children who received 30 mL/kg and -1·3 g/dL (-1·5 to -1·0) in those who received 20 mL/kg packed cells versus whole blood, and -1·5 g/dL (-1·7 to -1·3) in those who received 30 mL/kg and -1·0 g/dL (-1·2 to -0·9) in those who received 20 mL/kg settled cells versus whole blood (overall p<0·0001). Compared to whole blood, children who received blood as packed or settled cells in their first transfusion had higher odds of receiving a second transfusion (odds ratio 2·32 [95% CI 1·30 to 4·12] for packed cells and 2·97 [2·18 to 4·05] for settled cells; p<0·001) and longer hospital stays (hazard ratio 0·94 [95% CI 0·81 to 1·10] for packed cells and 0·86 [0·79 to 0·94] for settled cells; p=0·0024). There was no association between the type of blood supplied for the first transfusion and mortality at 28 days or 180 days, or readmission to hospital for any cause. 823 (26%) of 3188 children presented with severe tachycardia and 2077 (65%) with tachypnoea, but these complications resolved over time. No child developed features of confirmed cardiopulmonary overload. INTERPRETATION Our study suggests that the use of packed or settled cells rather than whole blood leads to additional transfusions, increasing the use of a scarce resource in most of sub-Saharan Africa. These findings have substantial cost implications for blood transfusion and health services. Nevertheless, a clinical trial comparing whole blood transfusion with red cell concentrates might be needed to inform policy makers. FUNDING UK Medical Research Council (MRC) and the Department for International Development. TRANSLATION For the French translation of the abstract see Supplementary Materials section.