Prophylactic tranexamic acid in patients with hematologic malignancy: a placebo-controlled, randomized clinical trial.

Evidence of the effectiveness of prophylactic use of tranexamic acid (TXA) in thrombocytopenia is lacking. To determine whether TXA safely reduces bleeding incidence in patients undergoing treatment for hematologic malignancies, a randomized, double-blind clinical trial was conducted from June 2016 through June 2020. Of 3120 screened adults, 356 patients were eligible and enrolled, and 337 patients (mean age, 53.9; 141 [41.8%] women), randomized to 1300 mg TXA orally or 1000 mg TXA through IV (n = 168) vs placebo (n = 169) thrice daily for maximum 30 days. Three hundred thirty patients were activated when their platelet counts fell below 30 000 per µL; 279 (83%) had complete outcome ascertainment. World Health Organization (WHO) grade ≥2 bleeding was observed in the 30 days following activation in 50.3% (73/145) and 54.2% (78/144) of patients in the TXA and placebo groups, with an adjusted odds ratio of 0.83 (95% confidence interval [CI], 0.50-1.34; P = .44). There was no statistically significant difference in the mean number of platelet transfusions (mean difference, 0.1; 95% CI, -1.9 to 2.0), mean days alive without grade ≥2 bleeding (mean difference, 0.8; 95% CI, -0.4 to 2.0), thrombotic events (6/163 [3.7%] TXA, 9/163 [5.5%] placebo), or deaths due to serious bleeding. Most common adverse events were: diarrhea (116/164 [70.7%] TXA and 114/163 [69.9%] placebo); febrile neutropenia (111/164 [67.7%] TXA, 105/163 [64.4%] placebo); fatigue (106/164 [64.6%] TXA, 109/163 [66.9%] placebo); and nausea (104/164 [63.4%] TXA, 97/163 [59.5%] placebo). Among patients with hematologic malignancy undergoing chemotherapy or hematopoietic stem cell transplantation, prophylactic treatment with TXA compared with placebo did not significantly reduce the risk of WHO grade ≥2 bleeding.

Amoxicillin for 3 or 5 Days for Chest-Indrawing Pneumonia in Malawian Children.

BACKGROUND: Evidence regarding the appropriate duration of treatment with antibiotic agents in children with pneumonia in low-resource settings in Africa is lacking. METHODS: We conducted a double-blind, randomized, controlled, noninferiority trial in Lilongwe, Malawi, to determine whether treatment with amoxicillin for 3 days is less effective than treatment for 5 days in children with chest-indrawing pneumonia (cough lasting <14 days or difficulty breathing, along with visible indrawing of the chest wall with or without fast breathing for age). Children not infected with human immunodeficiency virus (HIV) who were 2 to 59 months of age and had chest-indrawing pneumonia were randomly assigned to receive amoxicillin twice daily for either 3 days or 5 days. Children were followed for 14 days. The primary outcome was treatment failure by day 6; noninferiority of the 3-day regimen to the 5-day regimen would be shown if the percentage of children with treatment failure in the 3-day group was no more than 1.5 times that in the 5-day group. Prespecified secondary analyses included assessment of treatment failure or relapse by day 14. RESULTS: From March 29, 2016, to April 1, 2019, a total of 3000 children underwent randomization: 1497 children were assigned to the 3-day group, and 1503 to the 5-day group. Among children with day 6 data available, treatment failure had occurred in 5.9% in the 3-day group (85 of 1442 children) and in 5.2% (75 of 1456) in the 5-day group (adjusted difference, 0.7 percentage points; 95% confidence interval [CI], -0.9 to 2.4) - a result that satisfied the criterion for noninferiority of the 3-day regimen to the 5-day regimen. Among children with day 14 data available, 176 of 1411 children (12.5%) in the 3-day group and 154 of 1429 (10.8%) in the 5-day group had had treatment failure by day 6 or relapse by day 14 (between-group difference, 1.7 percentage points; 95% CI, -0.7 to 4.1). The percentage of children with serious adverse events was similar in the two groups (9.8% in the 3-day group and 8.8% in the 5-day group). CONCLUSIONS: In HIV-uninfected Malawian children, treatment with amoxicillin for chest-indrawing pneumonia for 3 days was noninferior to treatment for 5 days. (Funded by the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT02678195.).

Association of imbalance between job workload and functional ability with return to work in ARDS survivors.

BACKGROUND: Inability to return to work (RTW) is common after acute respiratory distress syndrome (ARDS). Mismatch in an individual's job workload and his or her functional ability, termed work ability imbalance, is negatively associated with RTW, but has not been evaluated in ARDS survivors. OBJECT: We examine associations between work ability imbalance at 6 months and RTW at 6 months and 12 months, as well as the ability to sustain employment in ARDS survivors. METHODS: Previously employed participants from the ARDS Network Long-Term Outcomes Study (N=341) were evaluated. Pre-ARDS workload was determined based on the US Occupational Information Network classification. Post-ARDS functional ability was assessed using self-reported 36-Item Short Form Health Survey (SF-36) physical functioning, social functioning and mental health subscales, and Mini-Mental State Examination. ARDS survivors were categorised into four work ability imbalance categories: none, psychosocial, physical, and both psychosocial and physical. RESULTS: Almost 90% of ARDS survivors had a physical and/or psychosocial work ability imbalance at both 6-month and 12-month follow-up. Compared with survivors with no imbalance at 6 months, those with both physical and psychosocial imbalance had lower odds of RTW (6 months: OR=0.33, 95% CI=0.13 to 0.82; 12 months: OR=0.22, 95% CI=0.07 to 0.65). Thirty-eight (19%) of those who ever RTW were subsequently jobless at 12 months. CONCLUSION: Interventions aimed at rebalancing ARDS survivors' work ability by addressing physical and psychosocial aspects of their functional ability and workload should be explored as part of efforts to improve RTW, maintain employment and reduce the financial impact of joblessness.

Paired serial limiting dilution assays.

Serial limiting dilution (SLD) assays are a widely used tool in many areas of public health research to measure the concentration of target entities. This concentration can be estimated via maximum likelihood. Asymptotic as well as exact inference methods have been proposed for hypothesis testing and confidence interval construction in this one-sample problem. However, in many scientific applications, it may be of interest to compare the concentration of target entities between a pair of samples and construct valid confidence intervals for the difference in concentrations. In this paper, an exact, computationally efficient inferential procedure is proposed for hypothesis testing and confidence interval construction in the two-sample SLD assay problem. The proposed exact method is compared to an approach based on asymptotic approximations in simulation studies. The methods are illustrated using data from the University of North Carolina HIV Cure Center.

Chest radiography in children aged 2-59 months enrolled in the Innovative Treatments in Pneumonia (ITIP) project in Lilongwe Malawi: a secondary analysis.

BACKGROUND: Pneumonia is the leading infectious cause of death in children aged under 5 years in low- and middle-income countries (LMICs). World Health Organization (WHO) pneumonia diagnosis guidelines rely on non-specific clinical features. We explore chest radiography (CXR) findings among select children in the Innovative Treatments in Pneumonia (ITIP) project in Malawi in relation to clinical outcomes. METHODS: When clinically indicated, CXRs were obtained from ITIP-enrolled children aged 2 to 59 months with community-acquired pneumonia hospitalized with treatment failure or relapse. ITIP1 (fast-breathing pneumonia) and ITIP2 (chest-indrawing pneumonia) trials enrolled children with non-severe pneumonia while ITIP3 enrolled children excluded from ITIP1 and ITIP2 with severe pneumonia and/or selected comorbidities. A panel of trained pediatricians classified the CXRs using the standardized WHO CXR research methodology. We analyzed the relationship between CXR classifications, enrollee characteristics, and outcomes. RESULTS: Between March 2016 and June 2018, of 114 CXRs obtained, 83 met analysis criteria with 62.7% (52/83) classified as having significant pathology per WHO standardized interpretation. ITIP3 (92.3%; 12/13) children had a higher proportion of CXRs with significant pathology compared to ITIP1 (57.1%, 12/21) and ITIP2 (57.1%, 28/49) (p-value = 0.008). The predominant pathological CXR reading was "other infiltrates only" in ITIP1 (83.3%, 10/12) and ITIP2 (71.4%, 20/28), while in ITIP3 it was "primary endpoint pneumonia"(66.7%, 8/12,; p-value = 0.008). The percent of CXRs with significant pathology among children clinically cured (60.6%, 40/66) vs those not clinically cured (70.6%, 12/17) at Day 14 was not significantly different (p-value = 0.58). CONCLUSIONS: In this secondary analysis we observed that ITIP3 children with severe pneumonia and/or selected comorbidities had a higher frequency of CXRs with significant pathology, although these radiographic findings had limited relationship to Day 14 outcomes. The proportion of CXRs with "primary endpoint pneumonia" was low. These findings add to existing data that additional diagnostics and prognostics are important for improving the care of children with pneumonia in LMICs. TRIAL REGISTRATION: ITIP1, ITIP2, and ITIP3 were registered with ClinicalTrials.gov ( NCT02760420 , NCT02678195 , and NCT02960919 , respectively).

Variation in Bystander Cardiopulmonary Resuscitation Delivery and Subsequent Survival From Out-of-Hospital Cardiac Arrest Based on Neighborhood-Level Ethnic Characteristics.

BACKGROUND: Bystander cardiopulmonary resuscitation (B-CPR) delivery and survival after out-of-hospital cardiac arrest vary at the neighborhood level, with lower survival seen in predominantly black neighborhoods. Although the Hispanic population is the fastest-growing minority population in the United States, few studies have assessed whether the proportion of Hispanic residents in a neighborhood is associated with B-CPR delivery and survival from out-of-hospital cardiac arrest. We assessed whether B-CPR rates and survival vary by neighborhood-level ethnicity. We hypothesized that neighborhoods with a higher proportion of Hispanic residents have lower B-CPR rates and lower survival. METHODS: We conducted a retrospective cohort study using data from the Resuscitation Outcomes Consortium Epistry at US sites. Neighborhoods were classified by census tract based on percentage of Hispanic residents: <25%, 25% to 50%, 51% to 75%, or >75%. We independently modeled the likelihood of receipt of B-CPR and survival by neighborhood-level ethnicity controlling for site and patient-level confounding characteristics. RESULTS: From 2011 to 2015, the Resuscitation Outcomes Consortium collected 27 481 US arrest events; after excluding pediatric arrests, emergency medical services-witnessed arrests, or arrests occurring in a healthcare or institutional facility, 18 927 were included. B-CPR was administered in 37% of events. In neighborhoods with <25% Hispanic residents, B-CPR was administered in 39% of events, whereas it was administered in 27% of events in neighborhoods with >75% Hispanic residents. Compared with <25% Hispanic neighborhoods in a multivariable analysis, out-of-hospital cardiac arrest in predominantly Hispanic neighborhoods had lower B-CPR rates (51% to 75% Hispanic: odds ratio, 0.79 [CI, 0.65-0.95], P=0.014; >75% Hispanic: odds ratio, 0.72 [CI, 0.55-0.96], P=0.025) and lower survival rates (global P value 0.029; >75% Hispanic: odds ratio, 0.56 [CI, 0.34-0.93], P=0.023). CONCLUSIONS: Individuals with out-of-hospital cardiac arrest in predominantly Hispanic neighborhoods were less likely to receive B-CPR and had lower likelihood of survival. These findings suggest a need to understand the underlying disparities in cardiopulmonary resuscitationdelivery and an unmet cardiopulmonary resuscitationtraining need in Hispanic communities.

Prediction-driven pooled testing methods: Application to HIV treatment monitoring in Rakai, Uganda.

Chronic medical conditions often necessitate regular testing for proper treatment. Regular testing of all afflicted individuals may not be feasible due to limited resources, as is true with HIV monitoring in resource-limited settings. Pooled testing methods have been developed in order to allow regular testing for all while reducing resource burden. However, the most commonly used methods do not make use of covariate information predictive of treatment failure, which could improve performance. We propose and evaluate four prediction-driven pooled testing methods that incorporate covariate information to improve pooled testing performance. We then compare these methods in the HIV treatment management setting to current methods with respect to testing efficiency, sensitivity, and number of testing rounds using simulated data and data collected in Rakai, Uganda. Results show that the prediction-driven methods increase efficiency by up to 20% compared with current methods while maintaining equivalent sensitivity and reducing number of testing rounds by up to 70%. When predictions were incorrect, the performance of prediction-based matrix methods remained robust. The best performing method using our motivating data from Rakai was a prediction-driven hybrid method, maintaining sensitivity over 96% and efficiency over 75% in likely scenarios. If these methods perform similarly in the field, they may contribute to improving mortality and reducing transmission in resource-limited settings. Although we evaluate our proposed pooling methods in the HIV treatment setting, they can be applied to any setting that necessitates testing of a quantitative biomarker for a threshold-based decision.

Stratified randomization for platform trials with differing experimental arm eligibility.

BACKGROUND: Platform trials facilitate efficient use of resources by comparing multiple experimental agents to a common standard of care arm. They can accommodate a changing scientific paradigm within a single trial protocol by adding or dropping experimental arms-critical features for trials in rapidly developing disease areas such as COVID-19 or cancer therapeutics. However, in these trials, efficacy and safety issues may render certain participant subgroups ineligible to some experimental arms, and methods for stratified randomization do not readily apply to this setting. METHODS: We propose extensions for conventional methods of stratified randomization for platform trials whose experimental arms may differ in eligibility criteria. These methods balance on a prespecified set of stratification variables observable prior to arm assignment that remains the same across experimental arms. To do so, we suggest modifying block randomization by including experimental arm eligibility as a stratifying variable, and we suggest modifying the imbalance score calculation in dynamic balancing by performing pairwise comparisons between each eligible experimental arm and standard of care arm participants eligible to that experimental arm. RESULTS: We provide worked examples to illustrate the proposed extensions. In addition, we also provide a formula to quantify the relative efficiency loss of platform trials with varying eligibility compared with trials with non-varying eligibility as measured by the size of the common standard of care arm. CONCLUSIONS: This article presents important extensions to conventional methods for stratified randomization in order to facilitate the implementation of platform trials with differing experimental arm eligibility.

Effect of Out-of-Hospital Sodium Nitrite on Survival to Hospital Admission After Cardiac Arrest: A Randomized Clinical Trial.

Importance: Therapeutic delivery of sodium nitrite during resuscitation improved survival in animal models of cardiac arrest, but efficacy has not been evaluated in clinical trials in humans. Objective: To determine whether parenteral administration of sodium nitrite given by paramedics during resuscitation for out-of-hospital cardiac arrest improved survival to hospital admission. Design, Setting, and Participants: Double-blind, placebo-controlled, phase 2 randomized clinical trial including 1502 adults in King County, Washington, with out-of-hospital cardiac arrest from ventricular fibrillation or nonventricular fibrillation. Patients underwent resuscitation by paramedics and were enrolled between February 8, 2018, and August 19, 2019; follow-up and data abstraction were completed by December 31, 2019. Interventions: Eligible patients with out-of-hospital cardiac arrest were randomized (1:1:1) to receive 45 mg of sodium nitrite (n = 500), 60 mg of sodium nitrite (n = 498), or placebo (n = 499), which was given via bolus injection by the paramedics as soon as possible during active resuscitation. Main Outcomes and Measures: The primary outcome was survival to hospital admission and was evaluated with 1-sided hypothesis testing. The secondary outcomes included out-of-hospital variables (rate of return of spontaneous circulation, rate of rearrest, and use of norepinephrine to support blood pressure) and in-hospital variables (survival to hospital discharge; neurological outcomes at hospital discharge; cumulative survival to 24 hours, 48 hours, and 72 hours; and number of days in the intensive care unit). Results: Among 1502 patients with out-of-hospital cardiac arrest who were randomized (mean age, 64 years [SD, 17 years]; 34% were women), 99% completed the trial. Overall, 205 patients (41%) in the 45 mg of sodium nitrite group and 212 patients (43%) in the 60 mg of sodium nitrite group compared with 218 patients (44%) in the placebo group survived to hospital admission; the mean difference for the 45-mg dose vs placebo was -2.9% (1-sided 95% CI, -8.0% to ∞; P = .82) and the mean difference for the 60-mg dose vs placebo was -1.3% (1-sided 95% CI, -6.5% to ∞; P = .66). None of the 7 prespecified secondary outcomes were significantly different, including survival to hospital discharge for 66 patients (13.2%) in the 45 mg of sodium nitrite group and 72 patients (14.5%) in the 60 mg of sodium nitrite group compared with 74 patients (14.9%) in the placebo group; the mean difference for the 45-mg dose vs placebo was -1.7% (2-sided 95% CI, -6.0% to 2.6%; P = .44) and the mean difference for the 60-mg dose vs placebo was -0.4% (2-sided 95% CI, -4.9% to 4.0%; P = .85). Conclusions and Relevance: Among patients with out-of-hospital cardiac arrest, administration of sodium nitrite, compared with placebo, did not significantly improve survival to hospital admission. These findings do not support the use of sodium nitrite during resuscitation from out-of-hospital cardiac arrest. Trial Registration: ClinicalTrials.gov Identifier: NCT03452917.

Comparative multi-assay evaluation of Determine™ HIV-1/2 Ag/Ab Combo rapid diagnostic tests in acute and chronic HIV infection.

In resource-limited or point-of-care settings, rapid diagnostic tests (RDTs), that aim to simultaneously detect HIV antibodies and p24 capsid (p24CA) antigen with high sensitivity, can pose important alternatives to screen for early infections. We evaluated the performance of the antibody and antigen components of the old and novel version of the Determine™ HIV-1/2 Ag/Ab Combo RDTs in parallel to quantifications in a fourth-generation antigen/antibody immunoassay (4G-EIA), p24CA antigen immunoassay (p24CA-EIA), immunoblots, and nucleic acid quantification. We included plasma samples of acute, treatment-naïve HIV-1 infections (Fiebig stages I-VI, subtypes A1, B, C, F, CRF02_AG, CRF02_AE, URF) or chronic HIV-1 and HIV-2 infections. The tests' antigen component was evaluated also for a panel of subtype B HIV-1 transmitted/founder (T/F) viruses, HIV-2 strains and HIV-2 primary isolates. Furthermore, we assessed the analytical sensitivity of the RDTs to detect p24CA using a highly purified HIV-1NL4-3 p24CA standard. We found that 77% of plasma samples from acutely infected, immunoblot-negative HIV-1 patients in Fiebig stages II-III were identified by the new RDT, while only 25% scored positive in the old RDT. Both RDTs reacted to all samples from chronically HIV-1-infected and acutely HIV-1-infected patients with positive immunoblots. All specimens from chronically infected HIV-2 patients scored positive in the new RDT. Of note, the sensitivity of the RDTs to detect recombinant p24CA from a subtype B virus ranged between 50 and 200 pg/mL, mirrored also by the detection of HIV-1 T/F viruses only at antigen concentrations tenfold higher than suggested by the manufacturer. The RTD failed to recognize any of the HIV-2 viruses tested. Our results indicate that the new version of the Determine™ HIV-1/2 Ag/Ab Combo displays an increased sensitivity to detect HIV-1 p24CA-positive, immunoblot-negative plasma samples compared to the precursor version. The sensitivity of 4G-EIA and p24CA-EIA to detect the major structural HIV antigen, and thus to diagnose acute infections prior to seroconversion, is still superior.

Non-inferiority designs comparing placebo to a proven therapy for childhood pneumonia in low-resource settings.

BACKGROUND/AIMS: After a new treatment is recommended to be first-line treatment for a specific indication, outcome and population, it may be unethical to use placebo as a comparator in trials for that setting. Nevertheless, in specific circumstances, use of a placebo group might be warranted, for example, when it is believed that an active treatment may not be efficacious or cost-effective for a specific subpopulation. An example is antibiotic treatment for pneumonia, which may not be effective for many patients taking it due to the emergence of antibiotic-resistant strains or the high prevalence of viral and low prevalence of bacterial pneumonia. METHODS: We explore the applicability of different design options in cases where the benefit of an established treatment is questioned, with particular emphasis on issues that arise in a low-resource setting. Using the example of a clinical trial comparing the effectiveness of placebo versus amoxicillin in treating children 2-59 months of age with fast breathing pneumonia in Lilongwe, Malawi, we discuss the pros and cons of superiority versus non-inferiority designs, an intent-to-treat versus as-treated analysis and the use and interpretation of one- versus two-sided confidence intervals. RESULTS: We find that a non-inferiority design using an intent-to-treat analysis is the most appropriate design and analysis option. In addition, the presentation of one- versus two-sided confidence intervals can depend on the results but can maintain type I error. CONCLUSION: In the setting where the benefit of a previously established beneficial treatment is questioned, a non-inferiority design that includes placebo as the tested treatment option can be the most appropriate design option.

Effect of Out-of-Hospital Tranexamic Acid vs Placebo on 6-Month Functional Neurologic Outcomes in Patients With Moderate or Severe Traumatic Brain Injury.

Importance: Traumatic brain injury (TBI) is the leading cause of death and disability due to trauma. Early administration of tranexamic acid may benefit patients with TBI. Objective: To determine whether tranexamic acid treatment initiated in the out-of-hospital setting within 2 hours of injury improves neurologic outcome in patients with moderate or severe TBI. Design, Setting, and Participants: Multicenter, double-blinded, randomized clinical trial at 20 trauma centers and 39 emergency medical services agencies in the US and Canada from May 2015 to November 2017. Eligible participants (N = 1280) included out-of-hospital patients with TBI aged 15 years or older with Glasgow Coma Scale score of 12 or less and systolic blood pressure of 90 mm Hg or higher. Interventions: Three interventions were evaluated, with treatment initiated within 2 hours of TBI: out-of-hospital tranexamic acid (1 g) bolus and in-hospital tranexamic acid (1 g) 8-hour infusion (bolus maintenance group; n = 312), out-of-hospital tranexamic acid (2 g) bolus and in-hospital placebo 8-hour infusion (bolus only group; n = 345), and out-of-hospital placebo bolus and in-hospital placebo 8-hour infusion (placebo group; n = 309). Main Outcomes and Measures: The primary outcome was favorable neurologic function at 6 months (Glasgow Outcome Scale-Extended score >4 [moderate disability or good recovery]) in the combined tranexamic acid group vs the placebo group. Asymmetric significance thresholds were set at 0.1 for benefit and 0.025 for harm. There were 18 secondary end points, of which 5 are reported in this article: 28-day mortality, 6-month Disability Rating Scale score (range, 0 [no disability] to 30 [death]), progression of intracranial hemorrhage, incidence of seizures, and incidence of thromboembolic events. Results: Among 1063 participants, a study drug was not administered to 96 randomized participants and 1 participant was excluded, resulting in 966 participants in the analysis population (mean age, 42 years; 255 [74%] male participants; mean Glasgow Coma Scale score, 8). Of these participants, 819 (84.8%) were available for primary outcome analysis at 6-month follow-up. The primary outcome occurred in 65% of patients in the tranexamic acid groups vs 62% in the placebo group (difference, 3.5%; [90% 1-sided confidence limit for benefit, -0.9%]; P = .16; [97.5% 1-sided confidence limit for harm, 10.2%]; P = .84). There was no statistically significant difference in 28-day mortality between the tranexamic acid groups vs the placebo group (14% vs 17%; difference, -2.9% [95% CI, -7.9% to 2.1%]; P = .26), 6-month Disability Rating Scale score (6.8 vs 7.6; difference, -0.9 [95% CI, -2.5 to 0.7]; P = .29), or progression of intracranial hemorrhage (16% vs 20%; difference, -5.4% [95% CI, -12.8% to 2.1%]; P = .16). Conclusions and Relevance: Among patients with moderate to severe TBI, out-of-hospital tranexamic acid administration within 2 hours of injury compared with placebo did not significantly improve 6-month neurologic outcome as measured by the Glasgow Outcome Scale-Extended. Trial Registration: ClinicalTrials.gov Identifier: NCT01990768.

Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests.

BACKGROUND: Survival following out-of-hospital cardiac arrest (OHCA) with shockable rhythms can be improved with early defibrillation. Although shockable OHCA accounts for only ≈25% of overall arrests, ≈60% of public OHCAs are shockable, offering the possibility of restoring thousands of individuals to full recovery with early defibrillation by bystanders. We sought to determine the association of bystander automated external defibrillator use with survival and functional outcomes in shockable observed public OHCA. METHODS: From 2011 to 2015, the Resuscitation Outcomes Consortium prospectively collected detailed information on all cardiac arrests at 9 regional centers. The exposures were shock administration by a bystander-applied automated external defibrillator in comparison with initial defibrillation by emergency medical services. The primary outcome measure was discharge with normal or near-normal (favorable) functional status defined as a modified Rankin Score ≤2. Survival to hospital discharge was the secondary outcome measure. RESULTS: Among 49 555 OHCAs, 4115 (8.3%) observed public OHCAs were analyzed, of which 2500 (60.8%) were shockable. A bystander shock was applied in 18.8% of the shockable arrests. Patients shocked by a bystander were significantly more likely to survive to discharge (66.5% versus 43.0%) and be discharged with favorable functional outcome (57.1% versus 32.7%) than patients initially shocked by emergency medical services. After adjusting for known predictors of outcome, the odds ratio associated with a bystander shock was 2.62 (95% confidence interval, 2.07-3.31) for survival to hospital discharge and 2.73 (95% confidence interval, 2.17-3.44) for discharge with favorable functional outcome. The benefit of bystander shock increased progressively as emergency medical services response time became longer. CONCLUSIONS: Bystander automated external defibrillator use before emergency medical services arrival in shockable observed public OHCA was associated with better survival and functional outcomes. Continued emphasis on public automated external defibrillator utilization programs may further improve outcomes of OHCA.

Trial of Continuous or Interrupted Chest Compressions during CPR.

BACKGROUND: During cardiopulmonary resuscitation (CPR) in patients with out-of-hospital cardiac arrest, the interruption of manual chest compressions for rescue breathing reduces blood flow and possibly survival. We assessed whether outcomes after continuous compressions with positive-pressure ventilation differed from those after compressions that were interrupted for ventilations at a ratio of 30 compressions to two ventilations. METHODS: This cluster-randomized trial with crossover included 114 emergency medical service (EMS) agencies. Adults with non-trauma-related cardiac arrest who were treated by EMS providers received continuous chest compressions (intervention group) or interrupted chest compressions (control group). The primary outcome was the rate of survival to hospital discharge. Secondary outcomes included the modified Rankin scale score (on a scale from 0 to 6, with a score of ≤3 indicating favorable neurologic function). CPR process was measured to assess compliance. RESULTS: Of 23,711 patients included in the primary analysis, 12,653 were assigned to the intervention group and 11,058 to the control group. A total of 1129 of 12,613 patients with available data (9.0%) in the intervention group and 1072 of 11,035 with available data (9.7%) in the control group survived until discharge (difference, -0.7 percentage points; 95% confidence interval [CI], -1.5 to 0.1; P=0.07); 7.0% of the patients in the intervention group and 7.7% of those in the control group survived with favorable neurologic function at discharge (difference, -0.6 percentage points; 95% CI, -1.4 to 0.1, P=0.09). Hospital-free survival was significantly shorter in the intervention group than in the control group (mean difference, -0.2 days; 95% CI, -0.3 to -0.1; P=0.004). CONCLUSIONS: In patients with out-of-hospital cardiac arrest, continuous chest compressions during CPR performed by EMS providers did not result in significantly higher rates of survival or favorable neurologic function than did interrupted chest compressions. (Funded by the National Heart, Lung, and Blood Institute and others; ROC CCC ClinicalTrials.gov number, NCT01372748.).

Methods for conducting a double-blind randomized controlled clinical trial of three days versus five days of amoxicillin dispersible tablets for chest indrawing childhood pneumonia among children two to 59 months of age in Lilongwe, Malawi: a study protocol.

BACKGROUND: Pneumonia is the leading infectious cause of death in children under 5 years of age around the globe. In addition to preventing pneumonia, there is a critical need to provide greater access to appropriate and effective treatment. Studies in Asia have evaluated the effectiveness of 3 days of oral amoxicillin for the treatment of fast-breathing pneumonia; however, further evidence is needed to determine if 3 days of oral amoxicillin is also effective for the treatment of chest indrawing pneumonia. METHODS: This is a double-blind, randomized, non-inferiority trial with the objective to assess the effectiveness of shorter duration amoxicillin dispersible tablet (DT) treatment of chest indrawing childhood pneumonia in a malaria-endemic region of Malawi. The primary objective of this study is to determine whether 3 days of treatment with oral amoxicillin DT in HIV-uninfected Malawian children two to 59 months of age with chest indrawing pneumonia is as effective as 5 days of treatment. The study will enroll 2000 children presenting to Kamuzu Central or Bwaila District Hospitals in Lilongwe, Malawi. Each child will be randomized to either 3 days of amoxicillin DT followed by 2 days of placebo DT or 5 days of amoxicillin DT. Children in the study will be hospitalized for 48 h after enrollment and will have scheduled study visits at Days 2, 4, 6 and 14. Treatment failure by Day 6 is the primary outcome. We hypothesize that the rates of treatment failure will be similar in both arms and that 3 days of treatment will be non-inferior to 5 days of amoxicillin DT for chest indrawing pneumonia using a relative non-inferiority margin of 1.5. This trial was approved by the Western Institutional Review Board and Malawi College of Medicine Research and Ethics Committee. DISCUSSION: Given the paucity of data from Africa, African-based research is necessary to establish appropriate duration of treatment with amoxicillin DT for chest indrawing childhood pneumonia in malaria-endemic settings in the region. An expanded evidence base will contribute to future iterations of World Health Organization Integrated Management of Childhood Illness guidelines. TRIAL REGISTRATION: NCT02678195 : Pre-results. Date registered February 9, 2016.

Effect of a Strategy of Initial Laryngeal Tube Insertion vs Endotracheal Intubation on 72-Hour Survival in Adults With Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial.

Importance: Emergency medical services (EMS) commonly perform endotracheal intubation (ETI) or insertion of supraglottic airways, such as the laryngeal tube (LT), on patients with out-of-hospital cardiac arrest (OHCA). The optimal method for OHCA advanced airway management is unknown. Objective: To compare the effectiveness of a strategy of initial LT insertion vs initial ETI in adults with OHCA. Design, Setting, and Participants: Multicenter pragmatic cluster-crossover clinical trial involving EMS agencies from the Resuscitation Outcomes Consortium. The trial included 3004 adults with OHCA and anticipated need for advanced airway management who were enrolled from December 1, 2015, to November 4, 2017. The final date of follow-up was November 10, 2017. Interventions: Twenty-seven EMS agencies were randomized in 13 clusters to initial airway management strategy with LT (n = 1505 patients) or ETI (n = 1499 patients), with crossover to the alternate strategy at 3- to 5-month intervals. Main Outcomes and Measures: The primary outcome was 72-hour survival. Secondary outcomes included return of spontaneous circulation, survival to hospital discharge, favorable neurological status at hospital discharge (Modified Rankin Scale score ≤3), and key adverse events. Results: Among 3004 enrolled patients (median [interquartile range] age, 64 [53-76] years, 1829 [60.9%] men), 3000 were included in the primary analysis. Rates of initial airway success were 90.3% with LT and 51.6% with ETI. Seventy-two hour survival was 18.3% in the LT group vs 15.4% in the ETI group (adjusted difference, 2.9% [95% CI, 0.2%-5.6%]; P = .04). Secondary outcomes in the LT group vs ETI group were return of spontaneous circulation (27.9% vs 24.3%; adjusted difference, 3.6% [95% CI, 0.3%-6.8%]; P = .03); hospital survival (10.8% vs 8.1%; adjusted difference, 2.7% [95% CI, 0.6%-4.8%]; P = .01); and favorable neurological status at discharge (7.1% vs 5.0%; adjusted difference, 2.1% [95% CI, 0.3%-3.8%]; P = .02). There were no significant differences in oropharyngeal or hypopharyngeal injury (0.2% vs 0.3%), airway swelling (1.1% vs 1.0%), or pneumonia or pneumonitis (26.1% vs 22.3%). Conclusions and Relevance: Among adults with OHCA, a strategy of initial LT insertion was associated with significantly greater 72-hour survival compared with a strategy of initial ETI. These findings suggest that LT insertion may be considered as an initial airway management strategy in patients with OHCA, but limitations of the pragmatic design, practice setting, and ETI performance characteristics suggest that further research is warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT02419573.

Relations between Household Livestock Ownership, Livestock Disease, and Young Child Growth.

BACKGROUND: In resource-limited settings in which child malnutrition is prevalent, humans live in close proximity to household livestock. However, the relation between household livestock and child nutrition represents a considerable knowledge gap. OBJECTIVE: We assessed whether household livestock ownership or livestock disease episodes were associated with growth in young children in western Kenya. METHODS: We incorporated monthly anthropometric measurements for children <5 y of age into an ongoing linked human and animal surveillance cohort in rural western Kenya. Using linear mixed models adjusted for age, sex, and household wealth, we tested whether baseline household livestock ownership was related to baseline child height for age or prospective growth rate. We also evaluated whether livestock disease episodes were associated with child growth rate over 11 mo of follow-up. RESULTS: We collected data on 925 children over the course of follow-up. Greater household livestock ownership at baseline was not related to baseline child height-for-age z score (adjusted ß: 0.01 SD; 95% CI: -0.02, 0.04 SD) or child growth rate (adjusted ß: 0.02 cm/y; 95% CI: -0.03, 0.07 cm/y). Livestock disease episodes were not significantly associated with child growth across the entire cohort (adjusted ß: -0.007 cm/mo; 95% CI: -0.02, 0.006 cm/mo). However, children in households with livestock digestive disease between June and November gained less height than did children in households that did not report livestock disease (ß: -0.063 cm/mo; 95% CI: -0.112, -0.016 cm/mo). Children <2 y of age in households with livestock digestive disease gained less weight than did those who did not report disease (ß: -0.033 kg/mo; 95% CI: -0.063, -0.003 kg/mo). CONCLUSION: In this cohort of young children in western Kenya, we did not find an association between ownership of livestock and child growth status. However, disease episodes in household livestock may be related to a lower child growth rate in some groups.

On estimation of covariate-specific residual time quantiles under the proportional hazards model.

Estimation and inference in time-to-event analysis typically focus on hazard functions and their ratios under the Cox proportional hazards model. These hazard functions, while popular in the statistical literature, are not always easily or intuitively communicated in clinical practice, such as in the settings of patient counseling or resource planning. Expressing and comparing quantiles of event times may allow for easier understanding. In this article we focus on residual time, i.e., the remaining time-to-event at an arbitrary time t given that the event has yet to occur by t. In particular, we develop estimation and inference procedures for covariate-specific quantiles of the residual time under the Cox model. Our methods and theory are assessed by simulations, and demonstrated in analysis of two real data sets.

A Comparison of Invasive Airway Management and Rates of Pneumonia in Prehospital and Hospital Settings.

INTRODUCTION: Infection is a major cause of morbidity and mortality in trauma. Infection in trauma is poorly understood. The impact of prehospital invasive airway management (IAM) on the incidence of pneumonia and health services utilization is unknown. We hypothesized that trauma patients exposed to prehospital IAM will suffer higher rates of pneumonia compared to no IAM or exposure to IAM performed in the hospital. We hypothesized that patients who develop pneumonia subsequent to prehospital IAM will have longer intensive care unit (ICU) and hospital length of stay (LOS) compared to patients who acquired pneumonia after IAM performed in the hospital. METHODS: This is an observational cohort study of data previously collected for the Resuscitation Outcomes Consortium hypertonic resuscitation randomized trial. Patients were included if traumatic injury resulted in shock, traumatic brain injury, or both. Patients were excluded if they died 24 hours after injury, or pneumonia data were missing. Adjusted and unadjusted logistic regression was used to calculate the odds ratio of pneumonia if exposed in the prehospital setting compared to no exposure or exposure in the hospital. RESULTS: Of 2,222 patients enrolled in the hypertonic resuscitation trial, 1,676 patients met enrollment criteria for this study. Four and a half percent of patients suffered pneumonia. IAM in the prehospital setting resulted in 6.8-fold increase (C.I. 2.0, 23.0, p = 0.003) in the adjusted odds of developing pneumonia compared to not being intubated, while in-hospital intubation resulted in 4.8-fold increase (C.I. 1.4, 16.6, p = 0.01), which was not statistically significantly different to the odds ratio of prehospital IAM. There were no statistically significant increases in health services utilization resulting from pneumonia incurred after IAM. CONCLUSION: Exposure to IAM in prehospital and hospital settings results in an increase in pneumonia, but there does not appear to be a link between the source of pneumonia and an increase in ICU or hospital LOS.