Anticoagulation practices associated with bleeding and thrombosis in pediatric extracorporeal membrane oxygenation; a multi-center secondary analysis

To determine associations between anticoagulation practices and bleeding and thrombosis during pediatric extracorporeal membrane oxygenation (ECMO), we performed a secondary analysis of prospectively collected data which included 481 children (<19 years), between January 2012 and September 2014. The primary outcome was bleeding or thrombotic events. Bleeding events included a blood product transfusion >80 ml/kg on any day, pulmonary hemorrhage, or intracranial bleeding, Thrombotic events included pulmonary emboli, intracranial clot, limb ischemia, cardiac clot, and arterial cannula or entire circuit change. Bleeding occurred in 42% of patients. Five percent of subjects thrombosed, of which 89% also bled. Daily bleeding odds were independently associated with day prior activated clotting time (ACT) (OR 1.03, 95% CI= 1.00, 1.05, p=0.047) and fibrinogen levels (OR 0.90, 95% CI 0.84, 0.96, p <0.001). Thrombosis odds decreased with increased day prior heparin dose (OR 0.88, 95% CI 0.81, 0.97, p=0.006). Lower ACT values and increased fibrinogen levels may be considered to decrease the odds of bleeding. Use of this single measure, however, may not be sufficient alone to guide optimal anticoagulation practice during ECMO.

A Bayesian Interpretation of a Pediatric Cardiac Arrest Trial (THAPCA-OH)

Bayesian Reanalysis of Pediatric Cardiac Arrest TrialOnly 7,000 children experience out-of-hospital cardiac arrest annually in the United States, and thus it is difficult to conduct large trials. This study presents a way to leverage all existing data by conducting a Bayesian reanalysis of the THAPCA-OH (Therapeutic Hypothermia after Pediatric Cardiac Arrest Out-of-Hospital) trial.

Methods Used to Maximize Follow-Up: Lessons Learned From the Therapeutic Hypothermia After Pediatric Cardiac Arrest Trials

OBJECTIVES

To describe telephone interview completion rates among 12-month cardiac arrest survivors enrolled in the Therapeutic Hypothermia after Pediatric Cardiac Arrest In-Hospital and Out-of-Hospital trials, identify key characteristics of the completed follow-up interviews at both 3- and 12-month postcardiac arrest, and describe strategies implemented to promote follow-up.

SETTING

Centralized telephone follow-up interviews.

DESIGN

Retrospective report of data collected for Therapeutic Hypothermia after Pediatric Cardiac Arrest trials, and summary of strategies used to maximize follow-up completion.

PATIENTS

Twelve-month survivors (n = 251) from 39 Therapeutic Hypothermia after Pediatric Cardiac Arrest PICU sites in the United States, Canada, and United Kingdom.

INTERVENTIONS

Not applicable.

MEASUREMENTS AND MAIN RESULTS

The 3- and 12-month telephone interviews included completion of the Vineland Adaptive Behavior Scales, Second Edition. Vineland Adaptive Behavior Scales, Second Edition data were available on 96% of 3-month survivors (242/251) and 95% of 12-month survivors (239/251) with no differences in demographics between those with and without completed Vineland Adaptive Behavior Scales, Second Edition. At 12 months, a substantial minority of interviews were completed with caregivers other than parents (10%), after calls attempts were made on 6 or more days (18%), and during evenings/weekends (17%). Strategies included emphasizing the relationship between study teams and participants, ongoing communication between study team members across sites, promoting site engagement during the study's final year, and withholding payment for work associated with the primary outcome until work had been completed.

CONCLUSIONS

It is feasible to use telephone follow-up interviews to successfully collect detailed neurobehavioral outcome about children following pediatric cardiac arrest. Future studies should consider availability of the telephone interviewer to conduct calls at times convenient for families, using a range of respondents, ongoing engagement with site teams, and site payment related to primary outcome completion.

Neuropsychological Outcomes of Children 1 Year After Pediatric Cardiac Arrest: Secondary Analysis of 2 Randomized Clinical Trials

Importance

Little is known about neuropsychological outcomes of children who survived pediatric cardiac arrest (CA).

Objective

To describe the neuropsychological outcomes of CA survivors enrolled in the Therapeutic Hypothermia After Pediatric Cardiac Arrest In-Hospital (THAPCA-IH) and Out-of-Hospital (THAPCA-OH) trials and compare the results with the primary outcome measure for these trials.

Design, Setting, and Participants

Secondary analysis of 222 CA survivors aged 1 to 18 years who received chest compressions for 2 minutes or more, remained comatose and required mechanical ventilation after return of circulation, and were enrolled in targeted temperature-management trials from 41 pediatric intensive care units. Data were collected from September 3, 2009, to February 3, 2016, and analyzed from March 10, 2017, to April 20, 2018.

Main Outcomes and Measures

The Vineland Adaptive Behavior Scales, Second Edition (VABS-II), a standardized measure of neurobehavioral functioning based on caregiver report (age-corrected mean [SD] scores = 100 [15]), was used to evaluate pre-CA functioning within 24 hours after enrollment; VABS-II<70 indicated significant developmental delays; VABS-II and neuropsychological testing were completed 1 year after CA. Neuropsychological testing included the Mullen Scales of Early Learning (Mullen) for children younger than 6 years and the Wechsler Abbreviated Scale of Intelligence (WASI) and neuropsychological measures of attention, memory, processing speed, and executive functioning for older children.

Results

Of 160 participants who completed neuropsychological testing, 96 (60.0%) were male; the median (interquartile range [IQR]) age was 2.5 years (1.3-6.1 years). Ninety-six (60.0%) were white, 41 (25.6%) were black, and 23 (14.4%) were of other/unknown race; 343 (21.2%) were Hispanic or Latino; 119 (74.4%) were non-Hispanic or Latino; and 7 (4.4%) were of unknown ethnicity. One hundred fourteen participants (71.2%) were classified as having favorable outcomes (VABS-II ≥70). Impairments (>2 SD below the mean for age) across neuropsychological measures ranged from 7% to 61%. Correlations between global cognitive and VABS-II scores were strong for younger children (Mullen, r = 0.69-0.87) but moderate for older children (r = 0.21-0.54 for the WASI). Of 111 children with favorable outcomes on VABS-II, 25.2% had global cognitive impairment and 30 of 35 older children (85.7%) had selective neuropsychological deficits.

Conclusions and Relevance

In this prospectively evaluated cohort of pediatric CA survivors who were initially comatose, although 71.2% were classified as having favorable outcomes, significant neuropsychological deficits were identified in pediatric CA survivors who were classified as having favorable outcomes. The findings provide clinicians with a greater understanding of the spectrum of neuropsychological outcomes of pediatric CA survivors and the complex relationship between standardized caregiver-reported functional outcome measures incorporated in clinical trials and performance-based neuropsychological assessments.

Functional outcomes among survivors of pediatric in-hospital cardiac arrest are associated with baseline neurologic and functional status, but not with diastolic blood pressure during CPR

AIM

Diastolic blood pressure (DBP) during cardiopulmonary resuscitation (CPR) is associated with survival following pediatric in-hospital cardiac arrest. The relationship between intra-arrest haemodynamics and neurological status among survivors of pediatric cardiac arrest is unknown.

METHODS

This study represents analysis of data from the prospective multicenter Pediatric Intensive Care Quality of cardiopulmonary resuscitation (PICqCPR) Study. Primary predictor variables were median DBP and median systolic blood pressure (SBP) over the first 10min of CPR. The primary outcome measure was "new substantive morbidity" determined by Functional Status Scale (FSS) and defined as an increase in the FSS of at least 3 points or increase of 2 in a single FSS domain. Univariable analyses were completed to investigate the relationship between new substantive morbidity and BPs during CPR.

RESULTS

244 index CPR events occurred during the study period, 77 (32%) CPR events met all inclusion criteria as well as having both DBP and FSS data available. Among 77 survivors, 32 (42%) had new substantive morbidity as measured by the FSS score. No significant differences were identified in DBP (median 30.5mmHg vs. 30.9mmHg, p=0.5) or SBP (median 76.3mmHg vs. 63.0mmHg, p=0.2) between patients with and without new substantive morbidity. Children who developed new substantive morbidity were more likely to have lower pre-arrest FSS than those that did not (median [IQR]: 7.5 [6.0-9.0] versus 9.0 [7.0-13.0], p=0.01).

CONCLUSION

New substantive morbidity determined by FSS after a pediatric IHCA was associated with baseline functional status, but not DBP during CPR.

The association of immediate post cardiac arrest diastolic hypertension and survival following pediatric cardiac arrest

AIM

In-hospital cardiac arrest occurs in >5000 children each year in the US and almost half will not survive to discharge. Animal data demonstrate that an immediate post-resuscitation burst of hypertension is associated with improved survival. We aimed to determine if systolic and diastolic invasive arterial blood pressures immediately (0-20 min) after return of spontaneous circulation (ROSC) are associated with survival and neurologic outcomes at hospital discharge.

METHODS

This is a secondary analysis of the Pediatric Intensive Care Quality of CPR (PICqCPR) study of invasively measured blood pressures during intensive care unit CPR. Patients were eligible if they achieved ROSC and had at least one invasively measured blood pressure within the first 20 min following ROSC. Post-ROSC blood pressures were normalized for age, sex and height. "Immediate hypertension" was defined as at least one systolic or diastolic blood pressure >90th percentile. The primary outcome was survival to hospital discharge.

RESULTS

Of 102 children, 70 (68.6%) had at least one episode of immediate post-CPR diastolic hypertension. After controlling for pre-existing hypotension, duration of CPR, calcium administration, and first documented rhythm, patients with immediate post-CPR diastolic hypertension were more likely to survive to hospital discharge (79.3% vs. 54.5%; adjusted OR = 2.93; 95%CI, 1.16-7.69).

CONCLUSIONS

In this post hoc secondary analysis of the PICqCPR study, 68.6% of subjects had diastolic hypertension within 20 min of ROSC. Immediate post-ROSC hypertension was associated with increased odds of survival to discharge, even after adjusting for covariates of interest.

The association of early post-resuscitation hypotension with discharge survival following targeted temperature management for pediatric in-hospital cardiac arrest

AIM

Approximately 40% of children who have an in-hospital cardiac arrest (IHCA) in the US survive to discharge. We aimed to evaluate the impact of post-cardiac arrest hypotension during targeted temperature management following IHCA on survival to discharge.

METHODS

This is a secondary analysis of the therapeutic hypothermia after pediatric cardiac arrest in-hospital (THAPCA-IH) trial. "Early hypotension" was defined as a systolic blood pressure less than the fifth percentile for age and sex for patients not treated with extracorporeal membrane oxygenation (ECMO) or a mean arterial pressure less than fifth percentile for age and sex for patients treated with ECMO during the first 6 h of temperature intervention. The primary outcome was survival to hospital discharge.

RESULTS

Of 299 children, 142 (47%) patients did not receive ECMO and 157 (53%) received ECMO. Forty-two of 142 (29.6%) non-ECMO patients had systolic hypotension. Twenty-three of 157 (14.7%) ECMO patients had mean arterial hypotension. After controlling for confounders of interest, non-ECMO patients who had early systolic hypotension were less likely to survive to hospital discharge (40.5% vs. 72%; adjusted OR [aOR] 0.34; 95%CI, 0.12-0.93). There was no difference in survival to discharge by blood pressure groups for children treated with ECMO (30.4% vs. 49.3%; aOR = 0.60; 95%CI, 0.22-1.63).

CONCLUSIONS

In this secondary analysis of the THAPCA-IH trial, in patients not treated with ECMO, systolic hypotension within 6 h of temperature intervention was associated with lower odds of discharge survival. Blood pressure groups in patients treated with ECMO were not associated with survival to discharge.

Development of the Pediatric Extracorporeal Membrane Oxygenation Prediction Model for Risk-Adjusting Mortality

OBJECTIVES

To develop a prognostic model for predicting mortality at time of extracorporeal membrane oxygenation initiation for children which is important for determining center-specific risk-adjusted outcomes.

DESIGN

Multivariable logistic regression using a large national cohort of pediatric extracorporeal membrane oxygenation patients.

SETTING

The ICUs of the eight tertiary care children's hospitals of the Collaborative Pediatric Critical Care Research Network.

PATIENTS

Five-hundred fourteen children (< 19 yr old), enrolled with an initial extracorporeal membrane oxygenation run for any indication between January 2012 and September 2014.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 514 first extracorporeal membrane oxygenation runs were analyzed with an overall mortality of 45% (n = 232). Weighted logistic regression was used for model selection and internal validation was performed using cross validation. The variables included in the Pediatric Extracorporeal Membrane Oxygenation Prediction model were age (pre-term neonate, full-term neonate, infant, child, and adolescent), indication for extracorporeal membrane oxygenation (extracorporeal cardiopulmonary resuscitation, cardiac, or respiratory), meconium aspiration, congenital diaphragmatic hernia, documented blood stream infection, arterial blood pH, partial thromboplastin time, and international normalized ratio. The highest risk of mortality was associated with the presence of a documented blood stream infection (odds ratio, 5.26; CI, 1.90-14.57) followed by extracorporeal cardiopulmonary resuscitation (odds ratio, 4.36; CI, 2.23-8.51). The C-statistic was 0.75 (95% CI, 0.70-0.80).

CONCLUSIONS

The Pediatric Extracorporeal Membrane Oxygenation Prediction model represents a model for predicting in-hospital mortality among children receiving extracorporeal membrane oxygenation support for any indication. Consequently, it holds promise as the first comprehensive pediatric extracorporeal membrane oxygenation risk stratification model which is important for benchmarking extracorporeal membrane oxygenation outcomes across many centers.

One-year cognitive and neurologic outcomes in survivors of paediatric extracorporeal cardiopulmonary resuscitation

OBJECTIVE

To describe one-year cognitive and neurologic outcomes among extracorporeal cardiopulmonary resuscitation (ECPR) survivors enrolled in the Therapeutic Hypothermia after Paediatric Cardiac Arrest In-Hospital (THAPCA-IH) trial; and compare outcomes between survivors who received ECPR, later extracorporeal membrane oxygenation (ECMO), or no ECMO.

METHODS

All children recruited to THAPCA-IH were comatose post-arrest. Neurobehavioral function was assessed by caregivers using the Vineland Adaptive Behaviour Scales, 2nd edition (VABS-II) at pre-arrest baseline and 12 months post-arrest. Age-appropriate cognitive performance measures (Mullen Scales of Early Learning or Wechsler Abbreviated Scale of Intelligence) and neurologic examinations were obtained 12 months post-arrest. VABS-II and cognitive performance measures were transformed to standard scores (mean = 100, SD = 15) with higher scores representing better performance. Only children with broadly normal pre-arrest function (VABS-II ≥70) were included in this analysis.

RESULTS

One-year follow-up was attained for 127 survivors with pre-arrest VABS-II ≥70. Of these, 57 received ECPR, 14 received ECMO later in their course, and 56 did not receive ECMO. VABS-II assessments were completed at 12 months for 55 (96.5%) ECPR survivors, cognitive testing for 44 (77.2%) and neurologic examination for 47 (82.5%). At 12 months, 39 (70.9%) ECPR survivors had VABS-II scores ≥70. On cognitive testing, 24 (54.6%) had scores ≥70, and on neurologic examination, 28 (59.5%) had no/minimal to mild impairment. Cognitive and neurologic score distributions were similar between ECPR, later ECMO and no ECMO groups.

CONCLUSIONS

Many ECPR survivors had favourable outcomes although impairments were common. ECPR survivors had similar outcomes to other survivors who were initially comatose post-arrest.

Pediatric out-of-hospital cardiac arrest: Time to goal target temperature and outcomes

AIM

Although recent out-of-hospital cardiac arrest (CA) trials found no benefits of hypothermia versus normothermia targeted temperature management, preclinical models suggest earlier timing of hypothermia improves neuroprotective efficacy. This study investigated whether shorter time to goal temperature was associated with better one-year outcomes in the Therapeutic Hypothermia After Pediatric Cardiac Arrest Out-of-Hospital Trial.

METHODS

Patients were classified by tertiles of time to attain assigned goal temperature range (32-34°C or 36-37.5°C) following ROSC. Outcomes in the first tertile ("earlier") Group 1 were compared with second and third tertiles ("later") Group 2. Separate analyses were, additionally, completed for hypothermia and normothermia intervention groups. Three one-year outcomes were examined: survival; Vineland Adaptive Behavior Scale (VABS-II) score≥70; and decrease in VABS-II≤15 points from baseline.

RESULTS

In the entire cohort (n=281), median time from ROSC to goal temperature was 7.4 [IQR 6.2-9.7] hours: Group 1, 5.8 [IQR 5.2, 6.2] and Group 2, 8.8 [IQR 7.4, 10.4] h. Outcomes did not differ between these groups. For hypothermia subgroup, survival was lower in Group 1 than 2, [10/49(20%) versus 47/99(47%), p<0.002], with a trend toward fewer with VABS-II scores≥70 and change in VABS-II≤15 points (p=0.07-0.08). For normothermia subgroup, there was a trend toward higher survival in Group 1 than 2 [18/42(43%) versus 21/83(25%), p=0.065], but no differences in VABS-II-related measures. In multivariable logistic regression models, no difference in earlier and later groups or temperature intervention was observed.

CONCLUSION

We found no evidence that earlier time to goal temperature was associated with better outcomes.

One-Year Survival and Neurologic Outcomes After Pediatric Open-Chest Cardiopulmonary Resuscitation

BACKGROUND

Limited data exist about neurobehavioral outcomes of children treated with open-chest cardiopulmonary resuscitation (CPR). Our objective was to describe neurobehavioral outcomes 1 year after arrest among children who received open-chest CPR during in-hospital cardiac arrest and to explore factors associated with 1-year survival and survival with good neurobehavioral outcome.

METHODS

The study is a secondary analysis of the Therapeutic Hypothermia after Pediatric Cardiac Arrest In-Hospital Trial. Fifty-six children who received open-chest CPR for in-hospital cardiac arrest were included. Neurobehavioral status was assessed using the Vineland Adaptive Behavior Scales, Second Edition (VABS-II) at baseline before arrest and 12 months after arrest. Norms for VABS-II are 100 ± 15 points. Outcomes included 12-month survival, 12-month survival with VABS-II decreased by no more than 15 points from baseline, and 12-month survival with VABS-II of 70 or more points.

RESULTS

Of 56 children receiving open-chest CPR, 49 (88%) were after cardiac surgery and 43 (77%) were younger than 1 year. Forty-four children (79%) were cannulated for extracorporeal membrane oxygenation (ECMO) during CPR or within 6 hours of return of spontaneous circulation. Thirty-three children (59%) survived to 12 months, 22 (41%) survived to 12 months with VABS-II decreased by no more than 15 points from baseline, and of the children with baseline VABS-II of 70 or more points 23 (51%) survived to 12 months with VABS-II of 70 or more points. On multivariable analyses, use of ECMO, renal replacement therapy, and higher maximum international normalized ratio were independently associated with lower 12-month survival with VABS-II of 70 or more points.

CONCLUSIONS

Approximately one-half of children survived with good neurobehavioral outcome 1 year after open-chest CPR for in-hospital cardiac arrest. Use of ECMO and postarrest renal or hepatic dysfunction may be associated with worse neurobehavioral outcomes.

Therapeutic hypothermia after paediatric cardiac arrest: Pooled randomized controlled trials

BACKGROUND

Separate trials to evaluate therapeutic hypothermia after paediatric cardiac arrest for out-of-hospital and in-hospital settings reported no statistically significant differences in survival with favourable neurobehavioral outcome or safety compared to therapeutic normothermia. However, larger sample sizes might detect smaller clinical effects. Our aim was to pool data from identically conducted trials to approximately double the sample size of the individual trials yielding greater statistical power to compare outcomes.

METHODS

Combine individual patient data from two clinical trials set in forty-one paediatric intensive care units in USA, Canada and UK. Children aged at least 48 h up to 18 years old, who remained comatose after resuscitation, were randomized within 6 h of return of circulation to hypothermia or normothermia (target 33.0 °C or 36.8 °C). The primary outcome, survival 12 months post-arrest with Vineland Adaptive Behaviour Scales, Second Edition (VABS-II) score at least 70 (scored from 20 to 160, higher scores reflecting better function, population mean = 100, SD = 15), was evaluated among patients with pre-arrest scores ≥70.

RESULTS

624 patients were randomized. Among 517 with pre-arrest VABS-II scores ≥70, the primary outcome did not significantly differ between hypothermia and normothermia groups (28% [75/271] and 26% [63/246], respectively; relative risk, 1.08; 95% confidence interval [CI], 0.81 to 1.42; p = 0.61). Among 602 evaluable patients, the change in VABS-II score from baseline to 12 months did not differ significantly between groups (p = 0.20), nor did, proportion of cases with declines no more than 15 points or improvement from baseline [22% (hypothermia) and 21% (normothermia)]. One-year survival did not differ significantly between hypothermia and normothermia groups (44% [138/317] and 38% [113/ 297], respectively; relative risk, 1.15; 95% CI, 0.95 to 1.38; p = 0.15). Incidences of blood-product use, infection, and serious cardiac arrhythmia adverse events, and 28-day mortality, did not differ between groups.

CONCLUSIONS

Analysis of combined data from two paediatric cardiac arrest targeted temperature management trials including both in-hospital and out-of-hospital cases revealed that hypothermia, as compared with normothermia, did not confer a significant benefit in survival with favourable functional outcome at one year.

End-tidal carbon dioxide during pediatric in-hospital cardiopulmonary resuscitation

BACKGROUND

Based on laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data, the American Heart Association Consensus Statement on CPR Quality recommends titrating CPR performance to achieve end-tidal carbon dioxide (ETCO2) >20 mmHg.

AIMS

We prospectively evaluated whether ETCO2 > 20 mmHg during CPR was associated with survival to hospital discharge.

METHODS

Children ≥37 weeks gestation in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 min and ETCO2 monitoring prior to and during CPR between July 1, 2013 and June 31, 2016 were included. ETCO2 and Utstein-style cardiac arrest data were collected. Multivariable Poisson regression models with robust error estimates were used to estimate relative risk of outcomes.

RESULTS

Blinded investigators analyzed ETCO2 waveforms from 43 children. During CPR, the median ETCO2 was 23 mmHg [quartiles, 16 and 28 mmHg], median ventilation rate was 29 breaths/min [quartiles, 24 and 35 breaths/min], and median duration of CPR was 5 min [quartiles, 2 and 16 min]. Return of spontaneous circulation occurred after 71% of CPR events and 37% of patients survived to hospital discharge. For children with mean ETCO2 during CPR > 20 mmHg, the adjusted relative risk for survival was 0.92 (0.41, 2.08), p = 0.84. The median mean ETCO2 among children who survived to hospital discharge was 20 mmHg [quartiles; 15, 28 mmHg] versus 23 mmHg [16, 28 mmHg] among non-survivors.

CONCLUSION

Mean ETCO2 > 20 mmHg during pediatric in-hospital CPR was not associated with survival to hospital discharge, and ETCO2 was not different in survivors versus non-survivors.

Practice Patterns after the Therapeutic Hypothermia After Pediatric Cardiac Arrest Out-of-Hospital Trial: A Survey of Pediatric Critical Care Physicians

The Therapeutic Hypothermia After Pediatric Cardiac Arrest Out-of-Hospital (THAPCA-OH) Trial showed therapeutic hypothermia, versus normothermia, did not significantly improve 1-year survival with good neurobehavioral outcome. Our survey of pediatric critical care physicians, designed to assess the use of targeted temperature management (TTM) after publication of the main THAPCA-OH Trial results, found most respondents were aware of trial results, and over 90% agreed THAPCA-OH was well-designed with important clinical outcomes. While most respondents reported TTM usage consistent with THAPCA-OH results in different patient scenarios, 15% did not select TTM for fever management. Since trials prior to THAPCA-OH established that fever is harmful following brain injury, the continued incomplete adoption of TTM warrants further research on challenges and facilitators to the adoption of clinical trial findings.

Acute kidney injury after out of hospital pediatric cardiac arrest

IMPORTANCE

Many children with return of spontaneous circulation (ROSC) following cardiac arrest (CA) experience acute kidney injury (AKI). The impact of therapeutic hypothermia on the epidemiology of post-CA AKI in children has not been fully investigated.

OBJECTIVE

The study aims were to: 1) describe the prevalence of severe AKI in comatose children following out-of-hospital CA (OHCA), 2) identify risk factors for severe AKI, 3) evaluate the impact of therapeutic hypothermia on the prevalence of severe AKI, and 4) evaluate the association of severe AKI with survival and functional outcomes.

DESIGN

A post hoc secondary analysis of data from the Therapeutic Hypothermia after Pediatric Cardiac Arrest Out-of-Hospital (THAPCA-OH) trial.

SETTING

Thirty-six pediatric intensive care units in the United States and Canada.

PARTICIPANTS

Of 282 eligible subjects with an initial creatinine obtained within 24 h of randomization, 148 were randomized to therapeutic hypothermia and 134 were randomized to therapeutic normothermia.

MAIN OUTCOMES AND MEASURES

Primary outcome was prevalence of severe AKI, as defined by stage 2 and 3 Kidney Disease Improving Global Outcomes (KDIGO) consensus definition; secondary outcome was survival with a favorable neurobehavioral outcome. For this study, risk factors and outcomes were compared between those with/without severe AKI.

RESULTS

Of the 282 subjects enrolled, 180 (64%) developed AKI of which 117 (41% of all enrolled) developed severe AKI. Multivariable modeling found younger age, longer duration of chest compressions, higher lactate level at time of temperature intervention and higher number of vasoactive agents through day 1 of intervention associated with severe AKI. There was no difference in severe AKI between therapeutic hypothermia (39.9%) and therapeutic normothermia (43.3%) groups (p = 0.629). Survival was lower in those with severe AKI at 28 days (21% vs no severe AKI 49%, p < 0.001) and 12 months (21% vs no severe AKI 42%, p < 0.001). One year survival with favorable functional outcome was lower in those with severe AKI.

CONCLUSIONS AND RELEVANCE

Severe AKI occurs frequently in children with ROSC after OHCA, especially in younger children and those with higher initial lactates and hemodynamic support. Severe AKI was associated with worse survival and functional outcome. Therapeutic hypothermia did not reduce the incidence of severe AKI.

Neurologic outcomes in pediatric cardiac arrest survivors enrolled in the THAPCA trials

OBJECTIVE

To implement a standardized approach to characterize neurologic outcomes among 12-month survivors in the Therapeutic Hypothermia after Pediatric Cardiac Arrest (THAPCA) trials.

METHODS

Two multicenter trials enrolled children age 48 hours to 18 years who remained comatose after cardiac arrest (CA) occurring out-of-hospital (THAPCA-OH, NCT00878644) or in-hospital (THAPCA-IH, NCT00880087); patients were randomized to therapeutic hypothermia or therapeutic normothermia. The primary outcome, survival with favorable 12-month neurobehavioral outcome (Vineland Adaptive Behavior Scales [VABS-II]), did not differ between treatment groups in either trial. Neurologists examined 181 12-month survivors, described findings using the novel semi-quantitative Pediatric Resuscitation after Cardiac Arrest (PRCA) form, and rated findings in 6 domains; scores ranged from 0 (no deficits) to 21 (maximal deficits). PRCA scores were compared with 12-month VABS-II scores and cognitive scores.

RESULTS

Neurologic outcome PRCA scores were classified as no/minimal impairment, PRCA 0-3, 81/179 (45%); mild impairment, PRCA 4-7, 24/179 (13%); moderate impairment, PRCA 8-11, 15/179 (8%); severe impairment, PRCA 12-16, 20/179 (11%); profound impairment, PRCA 17-21, 39/179 (21%) (2/181 incomplete). VABS-II scores correlated strongly with PRCA category (r = -0.88, p < 0.0001, Pearson correlation coefficient) and cognitive scores (r = -0.72, p < 0.0001). Factors associated with poor outcomes included out-of-hospital CA, seizure recognition in the early postarrest period, and poor neurologic status at hospital discharge.

CONCLUSION

The PRCA provides a robust method for depicting neurologic outcomes after acute encephalopathy caused by CA in children. It provides a global semiquantitative rating of neurologic impairment and domain-specific impairment. The strong correlation with well-established neurobehavioral outcome measures supports its validity over a broad age range and wide spectrum of outcomes.

Association Between Diastolic Blood Pressure During Pediatric In-Hospital Cardiopulmonary Resuscitation and Survival

BACKGROUND

On the basis of laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data demonstrating that survival depends on attaining adequate arterial diastolic blood pressure (DBP) during CPR, the American Heart Association recommends using blood pressure to guide pediatric CPR. However, evidence-based blood pressure targets during pediatric CPR remain an important knowledge gap for CPR guidelines.

METHODS

All children ≥37 weeks' gestation and <19 years old in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 minute and invasive arterial blood pressure monitoring before and during CPR between July 1, 2013, and June 31, 2016, were included. Mean DBP during CPR and Utstein-style standardized cardiac arrest data were collected. The hypothesis was that DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old would be associated with survival. Primary outcome was survival to hospital discharge. Secondary outcome was survival to hospital discharge with favorable neurological outcome, defined as Pediatric Cerebral Performance Categories 1 to 3 or no worse than prearrest baseline. Multivariable Poisson regression models with robust error estimates were used to estimate the relative risk of outcomes.

RESULTS

Blinded investigators analyzed blood pressure waveforms during CPR from 164 children, including 60% <1 year old, 60% with congenital heart disease, and 54% after cardiac surgery. The immediate cause of arrest was hypotension in 67%, respiratory decompensation in 44%, and arrhythmia in 19%. Median duration of CPR was 8 minutes (quartiles, 3 and 27 minutes). Ninety percent survived the event, 68% with return of spontaneous circulation and 22% by extracorporeal life support. Forty-seven percent survived to hospital discharge, and 43% survived to discharge with favorable neurological outcome. Maintaining mean DBP ≥25 mm Hg in infants and ≥30 mm Hg in children ≥1 year old occurred in 101 of 164 children (62%) and was associated with survival (adjusted relative risk, 1.7; 95% confidence interval, 1.2-2.6; P=0.007) and survival with favorable neurological outcome (adjusted relative risk, 1.6; 95% confidence interval, 1.1-2.5; P=0.02).

CONCLUSIONS

These data demonstrate that mean DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old was associated with greater likelihood of survival to hospital discharge and survival with favorable neurological outcome.

Burden of caregiving after a child's in-hospital cardiac arrest

OBJECTIVE

To describe caregiver burden among those whose children survive in-hospital cardiac arrest and have high risk of neurologic disability, and explore factors associated with burden during the first year post-arrest.

METHODS

The study is a secondary analysis of the Therapeutic Hypothermia after Paediatric Cardiac Arrest In-Hospital (THAPCA-IH) trial. 329 children who had an in-hospital cardiac arrest, chest compressions for >2 min, and mechanical ventilation after return of circulation were recruited to THAPCA-IH. Of these, 155 survived to one year, and caregivers of 138 were assessed for burden. Caregiver burden was assessed at baseline, and 3 and 12 months post-arrest using the Infant Toddler Quality of Life Questionnaire for children <5 years old and the Child Health Questionnaire for children >5 years. Child functioning was assessed using the Vineland Adaptive Behaviour Scales Second Edition (VABS-II), the Paediatric Overall Performance Category (POPC) and Paediatric Cerebral Performance Category (PCPC) scales, and caregiver perception of global functioning.

RESULTS

Of 138 children, 77 (55.8%) were male, 77 (55.8%) were white, and 109 (79.0%) were <5 years old at the time of arrest. Caregiver burden was greater than reference norms at all time points. Worse POPC, PCPC and VABS-II scores at 3 months post-arrest were associated with greater caregiver burden at 12 months. Worse global functioning at 3 months was associated with greater burden at 12 months for children <5 years.

CONCLUSIONS

Caregiver burden is substantial during the first year after paediatric in-hospital cardiac arrest, and associated with the extent of the child's neurobehavioural dysfunction.

Association of Early Postresuscitation Hypotension With Survival to Discharge After Targeted Temperature Management for Pediatric Out-of-Hospital Cardiac Arrest: Secondary Analysis of a Randomized Clinical Trial

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.

Neurobehavioural outcomes in children after In-Hospital cardiac arrest

AIM

Children who remain comatose after in-hospital cardiac arrest (IH-CA) resuscitation are at risk for poor neurological outcome. We report results of detailed neurobehavioural testing in paediatric IH-CA survivors, initially comatose after return of circulation, and enrolled in THAPCA-IH, a clinical trial that evaluated two targeted temperature management interventions (hypothermia, 33.0 °C or normothermia, 36.8 °C; NCT00880087).

METHODS

Children, aged 2 days to <18 years, were enrolled in THAPCA-IH from 2009 to 2015; primary trial outcome (survival with favorable neurobehavioural outcome) did not differ between groups. Pre-IH-CA neurobehavioural functioning, measured with the Vineland Adaptive Behavior Scales, Second Edition (VABS-II) was evaluated soon after enrollment; this report includes only children with broadly normal pre-IH-CA scores (VABS-II composite scores ≥70; 269 enrolled). VABS-II was re-administered 3 and 12 months later. Cognitive testing was completed at 12 months.

RESULTS

Follow-ups were obtained on 125 of 135 eligible one-year survivors. Seventy-seven percent (96/125) had VABS-II scores ≥70 at 12 months; cognitive composites were ≥2SD of mean in 59%. VABS-II composite, domain, and most subdomain scores declined between pre-IH-CA and 3-month, and pre-IH-CA and 12-month assessments (composite means declined about 1 SD at 3 and 12 months, p < 0.005); 3 and 12-month scores were strongly correlated (r = 0.72, p < 0.001).

CONCLUSIONS

In paediatric IH-CA survivors at high risk for unfavorable outcomes, the majority demonstrated significant declines in neurobehavioural functioning, across multiple functional domains, with similar functioning at 3 and 12 months. About three-quarters attained VABS-II functional performance composite scores within the broadly normal range.

Factors Associated with Bleeding and Thrombosis in Children Receiving Extracorporeal Membrane Oxygenation

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.

Hospital-level variation in inpatient cost among children receiving extracorporeal membrane oxygenation

OBJECTIVE

Pediatric extracorporeal membrane oxygenation (ECMO) varies in the way care is provided from hospital to hospital. This variability in hospital ECMO care can be represented by the variation in ECMO costs. We hypothesized that hospitals will demonstrate large variations in case-mix-adjusted ECMO inpatient costs for children requiring ECMO and higher volume hospitals will have lower associated costs.

METHODS

We retrospectively analyzed the inpatient cost of children receiving ECMO in 2006, 2009 and 2012, using the Healthcare Cost and Utilization Project Kids' Inpatient Database. We used a hierarchical linear regression model and the intraclass correlation coefficient to quantify how much of the difference in ECMO inpatient costs was associated with the hospital where a child received care. To do this, we adjusted for patient factors, hospital factors and potentially modifiable factors such as complications, procedures and length of stay.

RESULTS

The median inflation-adjusted inpatient costs for children requiring ECMO were $183,000, $240,000 and $241,000 in years 2006, 2009 and 2012, respectively. The largest median cost for ECMO cases in a given hospital in a given year ($690,000) was more than 11 times that of the smallest median cost ($60,000). After case-mix adjustment, 27% of the variation in inpatient costs was associated with the hospital where ECMO care was provided. Average hospital costs were not associated with hospital ECMO volume.

CONCLUSIONS

The large variation in ECMO inpatient costs between hospitals suggests great variation in care between hospitals, which is important because hospitals have a co-existing variation in ECMO survival rates.

Pediatric cardiac arrest due to drowning and other respiratory etiologies: Neurobehavioral outcomes in initially comatose children

AIM

To describe the 1-year neurobehavioral outcome of survivors of cardiac arrest secondary to drowning, compared with other respiratory etiologies, in children enrolled in the Therapeutic Hypothermia after Pediatric Cardiac Arrest Out-of-Hospital (THAPCA-OH) trial.

METHODS

Exploratory analysis of survivors (ages 1-18 years) who received chest compressions for ≥2min, were comatose, and required mechanical ventilation after return of circulation (ROC). Participants recruited from 27 pediatric intensive care units in North America received targeted temperature management [therapeutic hypothermia (33°C) or therapeutic normothermia (36.8°C)] within 6h of ROC. Neurobehavioral outcomes included 1-year Vineland Adaptive Behavior Scales, Second Edition (VABS-II) total and domain scores and age-appropriate cognitive performance measures (Mullen Scales of Early Learning or Wechsler Abbreviated Scale of Intelligence).

RESULTS

Sixty-six children with a respiratory etiology of cardiac arrest survived for 1-year; 60/66 had broadly normal premorbid functioning (VABS-II≥70). Follow up was obtained on 59/60 (30 with drowning etiology). VABS-II composite and domain scores declined significantly from premorbid scores in drowning and non-drowning groups (p<0.001), although declines were less pronounced for the drowning group. Seventy-two percent of children had well below average cognitive functioning at 1-year. Younger age, fewer doses of epinephrine, and drowning etiology were associated with better VABS-II composite scores. Demographic variables and treatment with hypothermia did not influence neurobehavioral outcomes.

CONCLUSIONS

Risks for poor neurobehavioral outcomes were high for children who were comatose after out-of-hospital cardiac arrest due to respiratory etiologies; survivors of drowning had better outcomes than those with other respiratory etiologies.

Therapeutic Hypothermia after In-Hospital Cardiac Arrest in Children

BACKGROUND

Targeted temperature management is recommended for comatose adults and children after out-of-hospital cardiac arrest; however, data on temperature management after in-hospital cardiac arrest are limited.

METHODS

In a trial conducted at 37 children's hospitals, we compared two temperature interventions in children who had had in-hospital cardiac arrest. Within 6 hours after the return of circulation, comatose children older than 48 hours and younger than 18 years of age were randomly assigned to therapeutic hypothermia (target temperature, 33.0°C) or therapeutic normothermia (target temperature, 36.8°C). The primary efficacy outcome, survival at 12 months after cardiac arrest with a score of 70 or higher on the Vineland Adaptive Behavior Scales, second edition (VABS-II, on which scores range from 20 to 160, with higher scores indicating better function), was evaluated among patients who had had a VABS-II score of at least 70 before the cardiac arrest.

RESULTS

The trial was terminated because of futility after 329 patients had undergone randomization. Among the 257 patients who had a VABS-II score of at least 70 before cardiac arrest and who could be evaluated, the rate of the primary efficacy outcome did not differ significantly between the hypothermia group and the normothermia group (36% [48 of 133 patients] and 39% [48 of 124 patients], respectively; relative risk, 0.92; 95% confidence interval [CI], 0.67 to 1.27; P=0.63). Among 317 patients who could be evaluated for change in neurobehavioral function, the change in VABS-II score from baseline to 12 months did not differ significantly between the groups (P=0.70). Among 327 patients who could be evaluated for 1-year survival, the rate of 1-year survival did not differ significantly between the hypothermia group and the normothermia group (49% [81 of 166 patients] and 46% [74 of 161 patients], respectively; relative risk, 1.07; 95% CI, 0.85 to 1.34; P=0.56). The incidences of blood-product use, infection, and serious adverse events, as well as 28-day mortality, did not differ significantly between groups.

CONCLUSIONS

Among comatose children who survived in-hospital cardiac arrest, therapeutic hypothermia, as compared with therapeutic normothermia, did not confer a significant benefit in survival with a favorable functional outcome at 1 year. (Funded by the National Heart, Lung, and Blood Institute; THAPCA-IH ClinicalTrials.gov number, NCT00880087 .).

Neurobehavioral Outcomes in Children After Out-of-Hospital Cardiac Arrest

OBJECTIVE

This study examined 12-month neurobehavioral outcomes in children who survived out-of-hospital cardiac arrest (OH-CA), were comatose after resuscitation, and were enrolled in a clinical trial to evaluate targeted temperature management to hypothermia (33.0°C) or normothermia (36.8°C) (Therapeutic Hypothermia after Pediatric Cardiac Arrest, Out-of-Hopsital [THAPCA-OH]; NCT00878644).

METHODS

Baseline functioning was assessed by caregiver responses on the Vineland Adaptive Behavior Scales-Second Edition (VABS-II) soon after OH-CA (based on functioning before OH-CA); children with broadly normal baseline functioning (VABS-II ≥70) were included in the THAPCA-OH primary outcome. VABS-II was completed again 12 months later. Then, face-to-face cognitive evaluations were completed. Analyses evaluated changes in VABS-II composite, domain, and subdomain scores and cognitive functioning at follow-up.

RESULTS

Ninety-six of 295 enrolled children were alive at 12 months; 87 of 96 had broadly normal baseline functioning (VABS-II ≥70). Follow-up was obtained on 85/87. Forty-two of 85 had VABS-II ≥70 at 12 months. VABS-II composite, domain, and subdomain scores declined significantly between baseline and 12-month follow-up (P < .001). Declines were greatest in older children. Most children displayed well below average cognitive functioning. Older age at cardiac arrest and higher baseline VABS-II scores were predictive of greater decline in neurobehavioral function. Treatment with hypothermia did not influence neurobehavioral outcomes.

CONCLUSIONS

This is the largest study exploring long-term neurobehavioral outcomes in children surviving OH-CA who were comatose after resuscitation. Results revealed significant neurobehavioral morbidity across multiple functional domains, based both on caregiver reports and performance on objective cognitive measures, in survivors 1 year later.

Development and validation of the pediatric risk estimate score for children using extracorporeal respiratory support (Ped-RESCUERS)

PURPOSE

To develop and validate the Pediatric Risk Estimation Score for Children Using Extracorporeal Respiratory Support (Ped-RESCUERS). Ped-RESCUERS is designed to estimate the in-hospital mortality risk for children prior to receiving respiratory extracorporeal membrane oxygenation (ECMO) support.

METHODS

This study used data from an international registry of patients aged 29 days to less than 18 years who received ECMO support from 2009 to 2014. We divided the registry into development and validation datasets by calendar date. Candidate variables were selected for model inclusion if the variable independently changed the mortality risk by at least 2 % in a Bayesian logistic regression model with in-hospital mortality as the outcome. We characterized the model's ability to discriminate mortality with the area under curve (AUC) of the receiver operating characteristic.

RESULTS

From 2009 to 2014, 2458 non-neonatal children received ECMO for respiratory support, with a mortality rate of 39.8 %. The development dataset contained 1611 children receiving ECMO support from 2009 to 2012. The model included the following variables: pre-ECMO pH, pre-ECMO arterial partial pressure of carbon dioxide, hours of intubation prior to ECMO support, hours of admission at ECMO center prior to ECMO support, ventilator type, mean airway pressure, pre-ECMO use of milrinone, and a diagnosis of pertussis, asthma, bronchiolitis, or malignancy. The validation dataset included 438 children receiving ECMO support from 2013 to 2014. The Ped-RESCUERS model from the development dataset had an AUC of 0.690, and the validation dataset had an AUC of 0.634.

CONCLUSIONS

Ped-RESCUERS provides a novel measure of pre-ECMO mortality risk. Future studies should seek external validation and improved discrimination of this mortality prediction tool.

Therapeutic hypothermia after out-of-hospital cardiac arrest in children

BACKGROUND

Therapeutic hypothermia is recommended for comatose adults after witnessed out-of-hospital cardiac arrest, but data about this intervention in children are limited.

METHODS

We conducted this trial of two targeted temperature interventions at 38 children's hospitals involving children who remained unconscious after out-of-hospital cardiac arrest. Within 6 hours after the return of circulation, comatose patients who were older than 2 days and younger than 18 years of age were randomly assigned to therapeutic hypothermia (target temperature, 33.0°C) or therapeutic normothermia (target temperature, 36.8°C). The primary efficacy outcome, survival at 12 months after cardiac arrest with a Vineland Adaptive Behavior Scales, second edition (VABS-II), score of 70 or higher (on a scale from 20 to 160, with higher scores indicating better function), was evaluated among patients with a VABS-II score of at least 70 before cardiac arrest.

RESULTS

A total of 295 patients underwent randomization. Among the 260 patients with data that could be evaluated and who had a VABS-II score of at least 70 before cardiac arrest, there was no significant difference in the primary outcome between the hypothermia group and the normothermia group (20% vs. 12%; relative likelihood, 1.54; 95% confidence interval [CI], 0.86 to 2.76; P=0.14). Among all the patients with data that could be evaluated, the change in the VABS-II score from baseline to 12 months was not significantly different (P=0.13) and 1-year survival was similar (38% in the hypothermia group vs. 29% in the normothermia group; relative likelihood, 1.29; 95% CI, 0.93 to 1.79; P=0.13). The groups had similar incidences of infection and serious arrhythmias, as well as similar use of blood products and 28-day mortality.

CONCLUSIONS

In comatose children who survived out-of-hospital cardiac arrest, therapeutic hypothermia, as compared with therapeutic normothermia, did not confer a significant benefit in survival with a good functional outcome at 1 year. (Funded by the National Heart, Lung, and Blood Institute and others; THAPCA-OH ClinicalTrials.gov number, NCT00878644.).

Rationale, timeline, study design, and protocol overview of the therapeutic hypothermia after pediatric cardiac arrest trials

OBJECTIVE

To describe the rationale, timeline, study design, and protocol overview of the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials.

DESIGN

Multicenter randomized controlled trials.

SETTING

Pediatric intensive care and cardiac ICUs in the United States and Canada.

PATIENTS

Children from 48 hours to 18 years old, who have return of circulation after cardiac arrest, who meet trial eligibility criteria, and whose guardians provide written consent.

INTERVENTIONS

Therapeutic hypothermia or therapeutic normothermia.

MEASUREMENTS AND MAIN RESULTS

From concept inception in 2002 until trial initiation in 2009, 7 years were required to plan and operationalize the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Two National Institute of Child Health and Human Development clinical trial planning grants (R21 and R34) supported feasibility assessment and protocol development. Two clinical research networks, Pediatric Emergency Care Applied Research Network and Collaborative Pediatric Critical Care Research Network, provided infrastructure resources. Two National Heart Lung Blood Institute U01 awards provided funding to conduct separate trials of in-hospital and out-of-hospital cardiac arrest. A pilot vanguard phase that included half the clinical sites began on March 9, 2009, and this was followed by full trial funding through 2015.

CONCLUSIONS

Over a decade will have been required to plan, design, operationalize, and conduct the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Details described in this report, such as participation of clinical research networks and clinical trial planning grants utilization, may be of utility for individuals who are planning investigator-initiated, federally supported clinical trials.

Early oxygenation and ventilation measurements after pediatric cardiac arrest: lack of association with outcome

OBJECTIVES

To explore oxygenation and ventilation status early after cardiac arrest in infants and children. We hypothesize that hyperoxia is common and associated with worse outcome after pediatric cardiac arrest.

DESIGN

Retrospective cohort study.

SETTING

Fifteen hospitals within the Pediatric Emergency Care Applied Research Network.

PATIENTS

Children who suffered a cardiac arrest event and survived for at least 6 hours after return of circulation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Analysis of 195 events revealed that abnormalities in oxygenation and ventilation are common during the initial 6 hours after pediatric cardiac arrest. Hyperoxia was frequent, affecting 54% of patients. Normoxia was documented in 34% and hypoxia in 22% of patients. These percentages account for a 10% overlap of patients who had both hyperoxia and hypoxia. Ventilation status was more evenly distributed with hyperventilation observed in 38%, normoventilation in 29%, and hypoventilation in 46%, with a 13% overlap of patients who had both hyperventilation and hypoventilation. Derangements in both oxygenation and ventilation were common early after cardiac arrest such that both normoxia and normocarbia were documented in only 25 patients (13%). Neither oxygenation nor ventilation status was associated with outcome. After controlling for potential confounders, arrest location and rhythm were significantly associated with worse outcome; however, hyperoxia was not (odds ratio for good outcome, 1.02 [0.46, 2.84]; p = 0.96).

CONCLUSIONS

Despite recent resuscitation guidelines that advocate maintenance of normoxia and normoventilation after pediatric cardiac arrest, this is uncommonly achieved in practice. Although we did not demonstrate an association between hyperoxia and worse outcome, the small proportion of patients kept within normal ranges limited our power. Preclinical data suggesting potential harm with hyperoxia remain compelling, and further investigation, including prospective, large studies involving robust recording of physiological derangements, is necessary to further advance our understanding of this important topic.

Fatal and near-fatal asthma in children: the critical care perspective

OBJECTIVE

To characterize the clinical course, therapies, and outcomes of children with fatal and near-fatal asthma admitted to pediatric intensive care units (PICUs).

STUDY DESIGN

This was a retrospective chart abstraction across the 8 tertiary care PICUs of the Collaborative Pediatric Critical Care Research Network (CPCCRN). Inclusion criteria were children (aged 1-18 years) admitted between 2005 and 2009 (inclusive) for asthma who received ventilation (near-fatal) or died (fatal). Data collected included medications, ventilator strategies, concomitant therapies, demographic information, and risk variables.

RESULTS

Of the 261 eligible children, 33 (13%) had no previous history of asthma, 218 (84%) survived with no known complications, and 32 (12%) had complications. Eleven (4%) died, 10 of whom had experienced cardiac arrest before admission. Patients intubated outside the PICU had a shorter duration of ventilation (median, 25 hours vs 84 hours; P < .001). African-Americans were disproportionately represented among the intubated children and had a shorter duration of intubation. Barotrauma occurred in 15 children (6%) before admission. Pharmacologic therapy was highly variable, with similar outcomes.

CONCLUSION

Of the children ventilated in the CPCCRN PICUs, 96% survived to hospital discharge. Most of the children who died experienced cardiac arrest before admission. Intubation outside the PICU was correlated with shorter duration of ventilation. Complications of barotrauma and neuromyopathy were uncommon. Practice patterns varied widely among the CPCCRN sites.

Critical care for pediatric asthma: wide care variability and challenges for study

OBJECTIVES

To describe pediatric severe asthma care, complications, and outcomes to plan for future prospective studies by the Collaborative Pediatric Critical Care Research Network.

DESIGN

Retrospective cohort study.

SETTING

: Pediatric intensive care units in the United States that submit administrative data to the Pediatric Health Information System.

PATIENTS

Children 1-18 yrs old treated in a Pediatric Health Information System pediatric intensive care unit for asthma during 2004-2008.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirteen-thousand five-hundred fifty-two children were studied; 2,812 (21%) were treated in a Collaborative Pediatric Critical Care Research Network and 10,740 (79%) were treated in a non-Collaborative Pediatric Critical Care Research Network pediatric intensive care unit. Medication use in individual Collaborative Pediatric Critical Care Research Network centers differed widely: ipratropium bromide (41%-84%), terbutaline (11%-74%), magnesium sulfate (23%-64%), and methylxanthines (0%-46%). Complications including pneumothorax (0%-0.6%), cardiac arrest (0.2%-2%), and aspiration (0.2%-2%) were rare. Overall use of medical therapies and complications at Collaborative Pediatric Critical Care Research Network centers were representative of pediatric asthma care at non-Collaborative Pediatric Critical Care Research Network pediatric intensive care units. Median length of pediatric intensive care unit stay at Collaborative Pediatric Critical Care Research Network centers was 1 to 2 days and death was rare (0.1%-3%). Ten percent of children treated at Collaborative Pediatric Critical Care Research Network centers received invasive mechanical ventilation compared to 12% at non-Collaborative Pediatric Critical Care Research Network centers. Overall 44% of patients who received invasive mechanical ventilation were intubated in the pediatric intensive care unit. Children intubated outside the pediatric intensive care unit had significantly shorter median ventilation days (1 vs. 3), pediatric intensive care unit days (2 vs. 4), and hospital days (4 vs. 7) compared to those intubated in the pediatric intensive care unit. Among children who received mechanical respiratory support, significantly more (41% vs. 25%) were treated with noninvasive ventilation and significantly fewer (41% vs. 58%) were intubated before pediatric intensive care unit care when treated in a Pediatric Health Information System hospital emergency department.

CONCLUSIONS

Marked variations in medication therapies and mechanical support exist. Death and other complications were rare. More than half of patients treated with mechanical ventilation were intubated before pediatric intensive care unit care. Site of respiratory mechanical support initiation was associated with length of stay.

Multicenter cohort study of out-of-hospital pediatric cardiac arrest

OBJECTIVES

To describe a large cohort of children with out-of-hospital cardiac arrest with return of circulation and to identify factors in the early postarrest period associated with survival. These objectives were for planning an interventional trial of therapeutic hypothermia after pediatric cardiac arrest.

METHODS

A retrospective cohort study was conducted at 15 Pediatric Emergency Care Applied Research Network clinical sites over an 18-month study period. All children from 1 day (24 hrs) to 18 yrs of age with out-of-hospital cardiac arrest and a history of at least 1 min of chest compressions with return of circulation for at least 20 mins were eligible.

MEASUREMENTS AND MAIN RESULTS

One hundred thirty-eight cases met study entry criteria; the overall mortality was 62% (85 of 138 cases). The event characteristics associated with increased survival were as follows: weekend arrests, cardiopulmonary resuscitation not ongoing at hospital arrival, arrest rhythm not asystole, no atropine or NaHCO3, fewer epinephrine doses, shorter duration of cardiopulmonary resuscitation, and drowning or asphyxial arrest event. For the 0- to 12-hr postarrest return-of-circulation period, absence of any vasopressor or inotropic agent (dopamine, epinephrine) use, higher lowest temperature recorded, greater lowest pH, lower lactate, lower maximum glucose, and normal pupillary responses were all associated with survival. A multivariate logistic model of variables available at the time of arrest, which controlled for gender, age, race, and asystole or ventricular fibrillation/ventricular tachycardia anytime during the arrest, found the administration of atropine and epinephrine to be associated with mortality. A second model using additional information available up to 12 hrs after return of circulation found 1) preexisting lung or airway disease; 2) an etiology of arrest drowning or asphyxia; 3) higher pH, and 4) bilateral reactive pupils to be associated with lower mortality. Receiving more than three doses of epinephrine was associated with poor outcome in 96% (44 of 46) of cases.

CONCLUSIONS

Multiple factors were identified as associated with survival after out-of-hospital pediatric cardiac arrest with the return of circulation. Additional information available within a few hours after the return of circulation may diminish outcome associations of factors available at earlier times in regression models. These factors should be considered in the design of future interventional trials aimed to improve outcome after pediatric cardiac arrest.

Multicenter cohort study of in-hospital pediatric cardiac arrest

OBJECTIVES

1) To describe clinical characteristics, hospital courses, and outcomes of a cohort of children cared for within the Pediatric Emergency Care Applied Research Network who experienced in-hospital cardiac arrest with sustained return of circulation between July 1, 2003 and December 31, 2004, and 2) to identify factors associated with hospital mortality in this population. These data are required to prepare a randomized trial of therapeutic hypothermia on neurobehavioral outcomes in children after in-hospital cardiac arrest.

DESIGN

Retrospective cohort study.

SETTING

Fifteen children's hospitals associated with Pediatric Emergency Care Applied Research Network.

PATIENTS

Patients between 1 day and 18 years of age who had cardiopulmonary resuscitation and received chest compressions for >1 min, and had a return of circulation for >20 mins.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 353 patients met entry criteria; 172 (48.7%) survived to hospital discharge. Among survivors, 132 (76.7%) had good neurologic outcome documented by Pediatric Cerebral Performance Category scores. After adjustment for age, gender, and first documented cardiac arrest rhythm, variables available before and during the arrest that were independently associated with increased mortality included pre-existing hematologic, oncologic, or immunologic disorders, genetic or metabolic disorders, presence of an endotracheal tube before the arrest, and use of sodium bicarbonate during the arrest. Variables associated with decreased mortality included postoperative cardiopulmonary resuscitation. Extending the time frame to include variables available before, during, and within 12 hours following arrest, variables independently associated with increased mortality included the use of calcium during the arrest. Variables associated with decreased mortality included higher minimum blood pH and pupillary responsiveness.

CONCLUSIONS

Many factors are associated with hospital mortality among children after in-hospital cardiac arrest and return of circulation. Such factors must be considered when designing a trial of therapeutic hypothermia after cardiac arrest in pediatric patients.

In-hospital versus out-of-hospital pediatric cardiac arrest: a multicenter cohort study

OBJECTIVES

: To describe a large multicenter cohort of pediatric cardiac arrest (CA) with return of circulation (ROC) from either the in-hospital (IH) or the out-of-hospital (OH) setting and to determine whether significant differences related to pre-event, arrest event, early postarrest event characteristics, and outcomes exist that would be critical in planning a clinical trial of therapeutic hypothermia (TH).

DESIGN

: Retrospective cohort study.

SETTING

: Fifteen Pediatric Emergency Care Applied Research Network sites.

PATIENTS

: Patients aged 24 hours to 18 years with either IH or OH CA who had a history of at least 1 minute of chest compressions and ROC for at least 20 minutes were eligible.

INTERVENTIONS

: None.

MEASUREMENTS AND MAIN RESULTS

: A total of 491 patients met study entry criteria with 353 IH cases and 138 OH cases. Major differences between the IH and OH cohorts were observed for patient prearrest characteristics, arrest event initial rhythm described, and arrest medication use. Several postarrest interventions were used differently, however, the use of TH was similar (<5%) in both cohorts. During the 0-12-hour interval following ROC, OH cases had lower minimum temperature and pH, and higher maximum serum glucose recorded. Mortality was greater in the OH cohort (62% vs. 51%, p = 0.04) with the cause attributed to a neurologic indication much more frequent in the OH than in the IH cohort (69% vs. 20%; p < 0.01).

CONCLUSIONS

: For pediatric CA with ROC, several major differences exist between IH and OH cohorts. The finding that the etiology of death was attributed to neurologic indications much more frequently in OH arrests has important implications for future research. Investigators planning to evaluate the efficacy of new interventions, such as TH, should be aware that the IH and OH populations differ greatly and require independent clinical trials.

Continuous quality improvement: reducing unplanned extubations in a pediatric intensive care unit

OBJECTIVE

Unplanned extubation (UEX) is a potentially serious complication of mechanical ventilation. Limited information is available regarding factors that contribute to UEXs and subsequent reintubation of children. We monitored UEXs in our pediatric intensive care unit (PICU) for a 5-year period to assess the incidence and patient conditions associated with UEX and to evaluate whether targeted interventions were associated with a reduced rate of UEXs.

METHODS

Over a 5-year period, demographic and clinical information was collected prospectively on all patients who required an artificial airway while admitted to the PICU. Additional information was collected for patients who experienced an UEX. Educational sessions and care management protocols were developed, implemented, and modified according to issues identified via the monitoring program.

RESULTS

From a total of 2192 patients who required 13 630 airway days (AWD), 141 (6%) patients experienced 164 UEXs. The overall rate of UEX for the study period was 1.2 UEXs per 100 AWD, and this rate decreased from 1.5 in the first year to 0.8 in the last year. UEXs were more common in children who were younger than 5 years (1.6 vs 0.6 UEX per 100 AWD) compared with older children. The UEX children experienced significantly longer length of mechanical ventilation (6 vs 3 days) and longer length of PICU stay (8 vs 4 days) compared with non-UEX children. Forty-six percent of the UEXs occurred in patients who were weaning from mechanical ventilation, and 22% of those patients required reintubation.

CONCLUSIONS

We conclude that UEX in pediatric patients is associated with longer length of mechanical ventilation and length of stay in the PICU. A continuous quality improvement monitoring and educational program that identified high-risk patients for UEX (younger patients) and patients who were at low risk for subsequent reintubation (weaning patients) contributed to a reduction of these potentially adverse events.

Outcome of pediatric patients treated with extracorporeal life support after cardiac surgery

BACKGROUND

Extracorporeal life support (ECLS) has been used for over two decades in select patients after cardiac surgery. We previously described factors associated with death in this population. We now review our recent experience to reassess factors related to mortality.

METHODS

All pediatric patients who received ECLS support within 7 days after surgery between July 1995 and June 2001 were examined to describe clinical features associated with survival. We compared the results with our prior report to assess changes in practice and outcome.

RESULTS

Seventy-four patients were followed. Fifty percent survived to discharge. Hospital survival was not significantly related to patient age, cannulation site, or indication. Thirty-five percent of patients required hemofiltration while on ECLS and were significantly less likely to survive (23% vs 65%). A multivariate analysis combining all children from our prior report with the present cohort revealed that patients who received hemofiltration were five times more likely to die (odds ratio 5.01, 95% confidence interval 2.11-11.88). Children with an adequate two-ventricular repair had lower risk of death (odds ratio 0.42, 95% confidence interval 0.19-0.91) after adjusting for patient age, study period, and hours elapsed before initiation of ECLS after surgery.

CONCLUSIONS

Patients with an adequate two-ventricle repair have significantly higher hospital survival, whereas those with single ventricle physiology or need for dialysis have decreased survival.

Nosocomial catheter-related bloodstream infections in a pediatric intensive care unit: risk and rates associated with various intravascular technologies

OBJECTIVE

Nosocomial bloodstream infections are associated with increased patient morbidity, mortality, and hospital costs. More than 90% of these infections are related to the use of intravascular catheter devices. This study was done to assess the risk and rates of catheter related-bloodstream infections (CR-BSI) associated with different intravascular technologies in a pediatric intensive care unit population.

DESIGN

Retrospective cohort study.

SETTING

A 16-bed pediatric intensive care unit in a tertiary children's hospital.

STUDY POPULATION

All admissions between July 1997 and December 1999 requiring placement of an intravascular access device for care were examined. Patients with CR-BSI were identified through ongoing surveillance using Centers for Disease Control/National Nosocomial Infections Surveillance System definitions for bloodstream infection.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 2,728 admissions during the review period, 1,043 (38.3%) required placement of an intravascular access device. Bivariate analysis revealed that patients who required intravascular cannulae for extracorporeal life support had a 10-fold increased risk of developing a CR-BSI, and patients requiring vascular access for renal replacement therapy demonstrated a 4-fold increase in the risk of developing CR-BSI compared with the referent group. There was a significant increase in the CR-BSI rate associated with the use of more intravascular access devices per patient admission. Multivariate logistic regression identified the use of extracorporeal life support therapy and the total duration of use of intravascular access devices as significant independent predictors of CR-BSI when controlling for other predictors.

CONCLUSION

The use of extracorporeal life support therapy, the presence of multiple intravascular access devices, and the total duration of intravascular access device use were associated with an increase in the rate and risk of developing CR-BSI in our pediatric intensive care unit population. Larger, prospective studies may help elucidate additional factors responsible for these observations.

Use of extracorporeal life support as a bridge to pediatric cardiac transplantation

BACKGROUND

Extracorporeal life support (ECLS) has been used for post-cardiotomy rescue, but its use as a bridge to heart transplantation (OHT) in patients with post-surgical or end-stage ventricular failure remains controversial.

METHODS

Records were reviewed for patients receiving ECLS for ventricular failure from January 1991 to August 2001. Patients listed for OHT were analyzed separately. Listing for OHT requirements were improbable myocardial recovery, absence of contraindications (central nervous system damage, high pulmonary resistance, ongoing infection, etc.), and parental consent. Outcome variables included patient demographics, diagnosis, days from ECLS initiation to United Network for Organ Sharing (UNOS) listing (latency), list time, renal function, and survival to discharge.

RESULTS

Of 145 patients with ventricular failure who received ECLS, 21 pediatric patients were UNOS listed. Of 124 non-listed patients, 57 (46%) survived to discharge. All but 3 survivors were separated from ECLS in </=7 days. Twelve underwent OHT and 10 survived to discharge (list time, 6 days; median ECLS time, 14 days). Five had ECLS discontinued without undergoing OHT (1 later underwent OHT, 2 survived to discharge). Five experienced complications while receiving ECLS and died without undergoing OHT. Six of 9 patients who required dialysis for renal failure died. Of 11 infants listed, 4 were weaned from ECLS without undergoing OHT (2 survived to discharge), 5 had OHT (ECLS support, 4 days; 4 survived to discharge) and 2 died (ECLS support, 16 and 47 days).

CONCLUSIONS

(1) Extracorporeal life support can be used as a bridge to OHT (even among the infant population) for at least 2 weeks with acceptable survival and hospital discharge rates, and (2) renal insufficiency with the concomitant requirement for dialysis decreases the likelihood of survival before and after OHT.

Pediatric Extracorporeal Life Support After High Frequency Ventilation: Predictors of Survival

Previous studies of extracorporeal life support in pediatric patients have identified variables associated with survival. However, none of these studies focused on extracorporeal life support after failure of high frequency ventilation (HFV). In the present study, we determined variables associated with survival for pediatric respiratory failure patients who received HFV prior to extracorporeal life support, using data reported to the Extracorporeal Life Support Organization Registry from 1992 to 1998. Patients with neonatal diagnoses, immune compromising conditions, or congenital cardiac defects were excluded. The 243 patients who met inclusion criteria had a 58% survival rate (95% CI 48-66%). The mean age was 22 +/- 39 months. Mean duration of mechanical ventilation prior to extracorporeal life support was 6.6 +/- 5.8 days. Venoarterial extracorporeal life support was used in 72% of the patients; venovenous in 28%. The survival rate for the subset of patients with an oxygenation index greater than 42 cm H2O/torr on HFV (n = 122) was not significantly different from the overall sample. We determined that lower mean airway pressure, lower pressure amplitude, decreased oxygenation index, increased PaO2, and increased oxygen saturation on HFV were associated with increased survival in patients who were subsequently treated with extracorporeal life support.

Cisatracurium infusion for neuromuscular blockade in the pediatric intensive care unit: A dose-finding study

OBJECTIVE: To evaluate the safety and efficacy of cisatracurium besylate, a neuromuscular blocking agent in infants zero to 2 yrs of age. DESIGN: An open-label study to evaluate efficacy and safety of cisatracurium as a continuous infusion in infants. SETTING: A tertiary pediatric intensive care unit. PATIENTS: Eleven children, 0-2 yrs of age, requiring prolonged neuromuscular blockade. INTERVENTIONS: Cisatracurium besylate, 0.1 mg/kg, was administered as an intravenous bolus dose and repeated if necessary until a >90% neuromuscular blockade, as determined by train-of-four response, was achieved. Patients were allowed to recover to 90% blockade (I/IV twitch) after the initial bolus and were administered continuous infusion at 2 &mgr;g/kg/min. The continuous infusion rate was adjusted to maintain a train-of-four response of 0-I/IV, with an increase in the rate preceded by a bolus dose of cisatracurium besylate. An electromyographic monitor was used to measure recovery at the end of infusion, when possible. Heart rate and blood pressure were recorded after the initial bolus dose and after changes in infusion rates. Blood samples were drawn at steady-state during cisatracurium infusion at several different times during the study and at the end of infusion for measurement of plasma cisatracurium and laudanosine concentrations. MEASUREMENTS AND MAIN RESULTS: The mean infusion rate of cisatracurium besylate required to maintain train-of-four response of 0-I/iv was 5.4 +/- 3.0 &mgr;g/kg/min. The mean total duration of infusion was 64.5 +/- 36 hrs. Ten percent and complete neuromuscular recovery occurred at 26.6 +/- 10.4 and 74.8 +/- 32 mins, respectively, after discontinuation of infusion. Mean cisatracurium and laudanosine concentrations were 342.5 +/- 169 and 163.3 +/- 116 ng/mL, respectively. Four (37%) patients had undetectable (<5 ng/mL) cisatracurium concentrations at the time of 100% neuromuscular recovery (train-of-four response of IV/IV or no fade at 50 mA on the electromyogram). No significant hemodynamic changes were observed during treatment with cisatracurium besylate (p <.05). CONCLUSIONS: A longer period of recovery from neuromuscular blockade was observed compared with reports of older children. Recovery from neuromuscular blockade after long-term use was not associated with any adverse events in the immediate postinfusion period. Cisatracurium besylate is a safe and effective neuromuscular blocking agent for children 0-2 yrs of age.

Extracorporal life support for pulmonary hemorrhage in children: a case series

OBJECTIVE

To examine the use and outcome of extracorporeal life support in children with severe respiratory failure caused by pulmonary hemorrhage.

DESIGN

Retrospective case series report.

SETTING

Pediatric intensive care unit in a university children's hospital.

PATIENTS

Eight patients <19 yrs of age who required extracorporeal life support for severe respiratory failure associated with pulmonary hemorrhage.

INTERVENTIONS

Venoarterial or venovenous extracorporeal life support.

MEASUREMENTS

Ventilatory support parameters and systemic PaO2/FiO2 ratio before extracorporeal life support, time on extracorporeal life support, number of ventilator days, number of intensive care unit days, number of hospital days, continued bleeding on extracorporeal life support, and survival.

MAIN RESULTS

All patients had resolution of their pulmonary hemorrhage within 24 hrs. All patients survived to decannulation, extubation, and hospital discharge. All patients are alive, with follow-up times ranging from 1 to 10 yrs.

CONCLUSIONS

Extracorporeal life support is not contraindicated in patients with severe respiratory failure with associated pulmonary hemorrhage and may be a life-sustaining supportive therapy.

Efficacy of recombinant human deoxyribonuclease I in the hospital management of respiratory syncytial virus bronchiolitis

OBJECTIVE

To evaluate the effect of recombinant human deoxyribonuclease I (rhDNase) in shortening the length of the hospitalization and improving the chest radiographs (CXRs) in hospitalized infants with respiratory syncytial virus (RSV) infection as a result of its mucolytic properties.

METHODS

Randomized, double-blind, placebo-controlled investigation of 75 patients with RSV bronchiolitis. The study was conducted at the University of Michigan Medical Center and St. Joseph Mercy Hospital, both in Ann Arbor, MI.

RESULTS

The respiratory rate, wheezing, and retraction difference scores, obtained by subtracting the hospital discharge score from the corresponding hospital admission score, show no difference between the two groups, but the CXR difference scores show that the rhDNase group improved by 0.46 while the placebo group worsened by 0.60 (p < 0.001). Analysis of covariance for the hospital discharge CXR score after adjusting for the hospital admission score for both groups was done. There was a difference in scores between the two groups, with adjusted mean for the study group of 2.03, and 2.76 for the placebo group (p < 0.001). Paired t test statistics in each of the two groups were computed. For the placebo group, the mean increase of 0.60 was significant (p = 0.02), and the mean decrease of 0.46 for the rhDNase group was also significant (p = 0.02). A one-way analysis of covariance with the hospital discharge CXR scores as the dependent variable and the hospital admission score as the covariate showed that there was a significant difference between the groups (p = 0.01).

CONCLUSION

In patients with RSV bronchiolitis, there was significant improvement in the CXRs with the use of rhDNase compared to significant worsening in the placebo group. To our knowledge, this is the first report of the use of rhDNase to treat RSV bronchiolitis.

Venovenous versus venoarterial extracorporeal life support for pediatric respiratory failure: are there differences in survival and acute complications?

OBJECTIVES

To examine the Extracorporeal Life Support Organization (ELSO) registry database of infants and children with acute respiratory failure to compare outcome and complications of venovenous (VV) vs. venoarterial (VA) Extracorporeal Life Support (ECLS).

DESIGN

Retrospective cohort study.

SETTING

ELSO registry for pediatric pulmonary support.

PATIENTS

All nonneonatal pediatric pulmonary support ECLS cases treated at U.S. centers and reported to the ELSO registry as of July 1997. Patients were excluded if they had one or more of the following diagnoses: hematologic-oncologic, cardiac, abdominal surgical, burn, metabolic, airway, or immunodeficiency disorder.

INTERVENTIONS

Venoarterial or venovenous extracorporeal life support for severe pulmonary failure.

MEASUREMENTS AND MAIN RESULTS

From 1986 to June of 1997, 763 pediatric patients met the inclusion criteria. Overall, 595 were initially managed with VA bypass, and 168 with VV bypass. The VA group was younger (mean +/- SD, 26.1+/-42.2 months for VA vs. 63.5+/-68.7 months for VV) and smaller (11.8+/-15.1 kg vs. 22.9+/-23.8 kg) (p<.001). There were no differences between groups in number of days on mechanical ventilation before ECLS, number of hours on ECLS, or number of hours on mechanical ventilation post-ECLS in survivors. Mean pH and Paco2 values, positive end-expiratory pressure, and mean airway pressure just before placing the patient on ECLS were also similar. VA-treated patients had higher Fio2 requirements (p = .034), lower Pao2 (p = .047), and lower Pao2/Fio2 ratio (p = .014) just before cannulation. There was a trend of higher peak inspiratory pressure in VA-treated patients (p = .053). Overall, survival rate was not different for the two groups (55.8% for VA vs. 60.1% for VV; p = .33). Central nervous system complications were not different between the two groups. Examination of the same variables was then conducted after dividing the patients into four subgroups. There were no significant differences in survival or complications during bypass between VV and VA modes of ECLS in any subgroup. Stepwise logistic regression modeling was performed to control for variables associated with the outcome survival for VV and VA-treated groups, and variables measured before bypass were identified as being associated with improved survival. There was a trend of improved survival in the VV-treated patients (p = .12).

CONCLUSIONS

Overall survival of pediatric patients with acute respiratory failure supported by VA or VV ECLS was comparable. A randomized clinical trial may be useful in clarifying these observations.

Severity of illness models for respiratory syncytial virus-associated hospitalization

The objective of this investigation was to examine the feasibility of multivariate severity of illness models for pediatric patients hospitalized with respiratory syncytial virus (RSV) infection. From a preexisting retrospective cohort study database, all infants and children 2 yr of age or younger with community-acquired RSV infection admitted to the University of Michigan's C. S. Mott Children's Hospital during nine epidemics were examined. The study group consisted of 802 hospitalized patients younger than 2 yr of age with community-acquired RSV infection; 182 (23%) patients had prolonged hospital length of stay defined as 7 d or greater. Multivariate logistic regression modeling of nine variables measurable during the first hospital day was strongly associated with prolonged hospitalization (p < 0.0001). Receiver operator characteristic curve analysis resulted in an area under the curve of 0.894, indicating excellent model discrimination. Goodness-of-fit testing indicated excellent model calibration for observed versus predicted outcomes (p = 0.216). We conclude that severity of illness models for RSV-associated hospitalization with excellent predictive properties in terms of classification, discrimination, and calibration are possible. Further study is required to determine if such models are generalizable across multiple centers and epidemics.