We report a Rh-catalyzed, enantioselective silylation of arene C-H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C-H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the other. Enantioenriched benzoxasiloles from the silylation process undergo a range of transformations to form C-C, C-O, C-I, or C-Br bonds.

Importance:Out-of-hospital cardiac arrest (OHCA) occurs in more than 6000 children each year in the United States, with survival rates of less than 10% and severe neurologic morbidity in many survivors. Post-cardiac arrest hypotension can occur, but its frequency and association with survival have not been well described during targeted temperature management. Objective:To determine whether hypotension is associated with survival to discharge in children and adolescents after resuscitation from OHCA. Design, Setting, and Participants:This post hoc secondary analysis of the Therapeutic Hypothermia After Pediatric Cardiac Arrest (THAPCA) trial included 292 pediatric patients older than 48 hours and younger than 18 years treated in 36 pediatric intensive care units from September 1, 2009, through December 31, 2012. Participants underwent therapeutic hypothermia (33.0°C) vs therapeutic normothermia (36.8°C) for 48 hours. All participants had hourly systolic blood pressure measurements documented during the initial 6 hours of temperature intervention. Hourly blood pressures beginning at the time of temperature intervention (time 0) were normalized for age, sex, and height. Early hypotension was defined as a systolic blood pressure less than the fifth percentile during the first 6 hours after temperature intervention. With use of forward stepwise logistic regression, covariates of interest (age, sex, initial cardiac rhythm, any preexisting condition, estimated duration of cardiopulmonary resuscitation [CPR], primary cause of cardiac arrest, temperature intervention group, night or weekend cardiac arrest, witnessed status, and bystander CPR) were evaluated in the final model. Data were analyzed from February 5, 2016, through June 13, 2017. Exposures:Hypotension. Main Outcomes and Measure:Survival to hospital discharge. Results:Of 292 children (194 boys [66.4%] and 98 girls [33.6%]; median age, 23.0 months [interquartile range, 5.0-105.0 months]), 78 (26.7%) had at least 1 episode of early hypotension. No difference was observed between the therapeutic hypothermia and therapeutic normothermia groups in the prevalence of hypotension during induction and maintenance (73 of 153 [47.7%] vs 72 of 139 [51.8%]; P = .50) or rewarming (35 of 118 [29.7%] vs 19 of 95 [20.0%]; P = .10) during the first 72 hours. Participants who had early hypotension were less likely to survive to hospital discharge (20 of 78 [25.6%] vs 93 of 214 [43.5%]; adjusted odds ratio, 0.39; 95% CI, 0.20-0.74). Conclusions and Relevance:In this post hoc secondary analysis of the THAPCA trial, 26.7% of participants had hypotension within 6 hours after temperature intervention. Early post-cardiac arrest hypotension was associated with lower odds of discharge survival, even after adjusting for covariates of interest.

Objectives

ICU length of stay is an important measure of resource use and economic performance. Our primary aims were to characterize the utilization of PICU beds and to develop a new model for PICU length of stay.

Design

Prospective cohort. The main outcomes were factors associated with PICU length of stay and the performance of a regression model for length of stay.

Setting

Eight PICUs.

Patients

Randomly selected patients (newborn to 18 yr) from eight PICUs were enrolled from December 4, 2011, to April 7, 2013. Data consisted of descriptive, diagnostic, physiologic, and therapeutic information.

Interventions

None.

Measurements and main results

The mean length of stay for was 5.0 days (SD, 11.1), with a median of 2.0 days. The 50.6% of patients with length of stay less than 2 days consumed only 11.1% of the days of care, whereas the 19.6% of patients with length of stay 4.9-19 days and the 4.6% with length of stay greater than or equal to 19 days consumed 35.7% and 37.6% of the days of care, respectively. Longer length of stay was observed in younger children, those with cardiorespiratory disease, postintervention cardiac patients, and those who were sicker assessed by Pediatric Risk of Mortality scores receiving more intensive therapies. Patients in the cardiac ICU stayed longer than those in the medical ICU. The length of stay model using descriptive, diagnostic, severity, and therapeutic factors performed well (patient-level R-squared of 0.42 and institution-level R-squared of 0.76). Standardized (observed divided by expected) length of stay ratios at the individual sites ranged from 0.87 to 1.09.

Conclusions

PICU bed utilization was dominated by a minority of patients. The 5% of patients staying the longest used almost 40% of the bed days. The multivariate length of stay model used descriptive, diagnostic, therapeutic, and severity factors and has potential applicability for internal and external benchmarking.

Objectives

Limited data exist on the effects of extracorporeal membrane oxygenation on pharmacokinetics of cefepime in critically ill pediatric patients. The objective was to describe cefepime disposition in children treated with extracorporeal membrane oxygenation using population pharmacokinetic modeling.

Design

Multicenter, prospective observational study.

Setting

The pediatric and cardiac ICUs of six sites of the Collaborative Pediatric Critical Care Research Network.

Patients

Seventeen critically ill children (30 d to < 2 yr old) on extracorporeal membrane oxygenation who received cefepime as standard of care between January 4, 2014, and August 24, 2015, were enrolled.

Interventions

None.

Measurements and main results

A pharmacokinetic model was developed to evaluate cefepime disposition differences due to extracorporeal membrane oxygenation. A two-compartment model with linear elimination, weight effects on clearance, intercompartmental clearance (Q), central volume of distribution (V1), and peripheral volume of distribution (V2) adequately described the data. The typical value of clearance in this study was 7.1 mL/min (1.9 mL/min/kg) for a patient weighing 5.8 kg. This value decreased by approximately 40% with the addition of renal replacement therapy. The typical value for V1 was 1,170 mL. In the setting of blood transfusions, V1 increased by over two-fold but was reduced with increasing age of the extracorporeal membrane oxygenation circuit oxygenator.

Conclusions

Cefepime clearance was reduced in pediatric patients treated with extracorporeal membrane oxygenation compared with previously reported values in children not receiving extracorporeal membrane oxygenation. The model demonstrated that the age of the extracorporeal membrane oxygenation circuit oxygenator is inversely correlated to V1. For free cefepime, only 14 of the 19 doses (74%) demonstrated a fT_minimum inhibitory concentration of 16 mg/L, an appropriate target for the treatment of pseudomonal infections, for greater than 70% of the dosing interval. Pediatric patients on extracorporeal membrane oxygenation might benefit from the addition of therapeutic drug monitoring of cefepime to assure appropriate dosing.

Objectives

The objective of this study was to associate ventilation rates during in-hospital cardiopulmonary resuscitation with 1) arterial blood pressure during cardiopulmonary resuscitation and 2) survival outcomes.

Design

Prospective, multicenter observational study.

Setting

Pediatric and pediatric cardiac ICUs of the Collaborative Pediatric Critical Care Research Network.

Patients

Intubated children (≥ 37 wk gestation and < 19 yr old) who received at least 1 minute of cardiopulmonary resuscitation.

Interventions

None.

Measurements and main results

Arterial blood pressure and ventilation rate (breaths/min) were manually extracted from arterial line and capnogram waveforms. Guideline rate was defined as 10 ± 2 breaths/min; high ventilation rate as greater than or equal to 30 breaths/min in children less than 1 year old, and greater than or equal to 25 breaths/min in older children. The primary outcome was survival to hospital discharge. Regression models using Firth penalized likelihood assessed the association between ventilation rates and outcomes. Ventilation rates were available for 52 events (47 patients). More than half of patients (30/47; 64%) were less than 1 year old. Eighteen patients (38%) survived to discharge. Median event-level average ventilation rate was 29.8 breaths/min (interquartile range, 23.8-35.7). No event-level average ventilation rate was within guidelines; 30 events (58%) had high ventilation rates. The only significant association between ventilation rate and arterial blood pressure occurred in children 1 year old or older and was present for systolic blood pressure only (-17.8 mm Hg/10 breaths/min; 95% CI, -27.6 to -8.1; p < 0.01). High ventilation rates were associated with a higher odds of survival to discharge (odds ratio, 4.73; p = 0.029). This association was stable after individually controlling for location (adjusted odds ratio, 5.97; p = 0.022), initial rhythm (adjusted odds ratio, 3.87; p = 0.066), and time of day (adjusted odds ratio, 4.12; p = 0.049).

Conclusions

In this multicenter cohort, ventilation rates exceeding guidelines were common. Among the range of rates delivered, higher rates were associated with improved survival to hospital discharge.

Rationale

Extracorporeal membrane oxygenation (ECMO) is used for respiratory and cardiac failure in children but is complicated by bleeding and thrombosis.

Objectives

(1) To measure the incidence of bleeding (blood loss requiring transfusion or intracranial hemorrhage) and thrombosis during ECMO support; (2) to identify factors associated with these complications; and (3) to determine the impact of these complications on patient outcome.

Methods

This was a prospective, observational cohort study in pediatric, cardiac, and neonatal intensive care units in eight hospitals, carried out from December 2012 to September 2014.

Measurements and main results

ECMO was used on 514 consecutive patients under age 19 years. Demographics, anticoagulation practices, severity of illness, circuitry components, bleeding, thrombotic events, and outcome were recorded. Survival was 54.9%. Bleeding occurred in 70.2%, including intracranial hemorrhage in 16%, and was independently associated with higher daily risk of mortality. Circuit component changes were required in 31.1%, and patient-related clots occurred in 12.8%. Laboratory sampling contributed to transfusion requirement in 56.6%, and was the sole reason for at least one transfusion in 42.2% of patients. Pump type was not associated with bleeding, thrombosis, hemolysis, or mortality. Hemolysis was predictive of subsequent thrombotic events. Neither hemolysis nor thrombotic events increased the risk of mortality.

Conclusions

The incidences of bleeding and thrombosis are high during ECMO support. Laboratory sampling is a major contributor to transfusion during ECMO. Strategies to reduce the daily risk of bleeding and thrombosis, and different thresholds for transfusion, may be appropriate subjects of future trials to improve outcomes of children requiring this supportive therapy.

OBJECTIVES: To evaluate associations between sodium bicarbonate use and outcomes during pediatric in-hospital cardiac arrest (p-IHCA). DESIGN: Prespecified secondary analysis of a prospective, multicenter cluster randomized interventional trial. SETTING: Eighteen participating ICUs of the ICU-RESUScitation Project (NCT02837497). PATIENTS: Children less than or equal to 18 years old and greater than or equal to 37 weeks post conceptual age who received chest compressions of any duration from October 2016 to March 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Child and event characteristics, prearrest laboratory values (2-6 hr prior to p-IHCA), pre- and intraarrest hemodynamics, and outcomes were collected. In a propensity score weighted cohort, the relationships between sodium bicarbonate use and outcomes were assessed. The primary outcome was survival to hospital discharge. Secondary outcomes included return of spontaneous circulation (ROSC) and survival to hospital discharge with favorable neurologic outcome. Of 1,100 index cardiopulmonary resuscitation events, median age was 0.63 years (interquartile range, 0.19-3.81 yr); 528 (48.0%) received sodium bicarbonate; 773 (70.3%) achieved ROSC; 642 (58.4%) survived to hospital discharge; and 596 (54.2%) survived to hospital discharge with favorable neurologic outcome. Among the weighted cohort, sodium bicarbonate use was associated with lower survival to hospital discharge rate (adjusted odds ratio [aOR], 0.7; 95% CI, 0.54-0.92; p = 0.01) and lower survival to hospital discharge with favorable neurologic outcome rate (aOR, 0.69; 95% CI, 0.53-0.91; p = 0.007). Sodium bicarbonate use was not associated with ROSC (aOR, 0.91; 95% CI, 0.62-1.34; p = 0.621). CONCLUSIONS: In this propensity weighted multicenter cohort study of p-IHCA, sodium bicarbonate use was common and associated with lower rates of survival to hospital discharge.