Chest Compression Depth Targets in Critically Ill Infants and Children Measured With a Laser Distance Meter: Single-Center Retrospective Study From Japan, 2019-2022

OBJECTIVES

Current resuscitation guidelines recommend target chest compression depth (CCd) of approximately 4cm for infants and 5cm for children. Previous reports based on chest CT suggest these recommended CCd targets might be too deep for younger children. Our aim was to examine measurements of anterior-posterior chest diameter (APd) with a laser distance meter and calculate CCd targets in critically ill infants and children.

DESIGN

A retrospective descriptive study.

SETTING

Single-center PICU, using data from May 2019 to May 2022.

PATIENTS

All critically ill children admitted to PICU and under 8 years old were eligible to be included in the retrospective cohort.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The chest APd measurements using a laser distance meter are part of our usual practice on the PICU. Target CCd and the over-compression threshold CCd for each age group was calculated as 1/3 and 1/2 of APd, respectively. In 555 patients, the median (interquartile range) of the calculated target CCd for each age group was: 2.7 cm (2.5-2.9 cm), 2.9 cm (2.7-3.2 cm), 3.2 cm (3-3.5 cm), 3.4 cm (3.2-3.6 cm), 3.4 cm (3.2-3.6 cm), 3.6 cm (3.4-3.8 cm), 3.6 cm (3.4-4 cm), and 4 cm (3.5-4.2 cm), for 0, 2, 3-5, 6-8, 9-11, 12-17, 18-23, 24 to less than 60, and 60 to less than 96 months, respectively. Using guideline-recommended absolute CCd targets, 4 cm for infants and 5 cm for children, 49% of infants between 0 and 2 months, and 45.5% of children between 12 and 17 months would be over-compressed during cardiopulmonary resuscitation.

CONCLUSIONS

In our cohort, the 1/3 CCd targets calculated from APd measured by laser meter were shallower than the guideline-recommended CCd. Further studies including evaluating hemodynamics during cardiopulmonary resuscitation with these shallower CCd targets are needed.

Association of blood pressure with neurologic outcome at hospital discharge after pediatric cardiac arrest resuscitation

BACKGROUND

Poor outcomes are associated with post cardiac arrest blood pressures <5th percentile for age. We aimed to study the relationship of mean arterial pressure (MAP) with favorable neurologic outcome following cardiac arrest and return of spontaneous circulation (ROSC).

METHODS

This retrospective, multi-center, observational study analyzed data from the Pediatric Resuscitation Quality Collaborative (pediRES-Q). Children (<18 years) who achieved ROSC following index in-hospital or out-of-hospital cardiac arrest and survived ≥6 hours were included. Lowest documented MAP within the first 6 hours of ROSC was percentile adjusted for age and categorized into six groups - Group I: <5th, II: 5-24th, III: 25-49th, IV: 50-74th, V: 75-94th; and VI: 95-100th percentile. Primary outcome was favorable neurologic status at hospital discharge, defined as PCPC score 1, 2, or no change from pre-arrest baseline. Multivariable logistic regression was performed to analyze the association of MAP group with favorable outcome, controlling for illness category (surgical-cardiac), initial rhythm (shockable), arrest time (weekend or overnight), age, CPR duration, and clustering by site.

RESULTS

787 patients were included: median [Q1,Q3] age 17.9 [4.8,90.6] months; male 58%; OHCA 21%; shockable rhythm 13%; CPR duration 7 [3,16] min; favorable neurologic outcome 54%. Median lowest documented MAP percentile for the favorable outcome group was 13 [3,43] versus 8 [1,37] for the unfavorable group. The distribution of blood pressures by MAP group was I: 37%, II: 28%, III: 13%, IV: 11%, V: 7%, and VI: 4%. Compared with patients in Group I (<5%ile), Groups II, III, and IV had higher odds of favorable outcome (aOR, 1.84 [95% CI, 1.24, 2.73]; 2.20 [95% CI, 1.32, 3.68]; 1.90 [95% CI, 1.12, 3.25]). There was no association between Groups V or VI and favorable outcome (aOR, 1.44 [95% CI, 0.75, 2.80]; 1.11 [95% CI, 0.47, 2.59]).

CONCLUSION

In the first 6-hours post-ROSC, a lowest documented MAP between the 5th-74th percentile for age was associated with favorable neurologic outcome compared to MAP <5th percentile for age.

Association of Chest Compression Pause Duration Prior to E-CPR Cannulation with Cardiac Arrest Survival Outcomes

OBJECTIVE

To characterize chest compression (CC) pause duration during the last 5 minutes of pediatric cardiopulmonary resuscitation (CPR) prior to extracorporeal-CPR (E-CPR) cannulation and the association with survival outcomes.

METHODS

Cohort study from a resuscitation quality collaborative including pediatric E-CPR cardiac arrest events ≥10 min with CPR quality data. We characterized CC interruptions during the last 5 min of defibrillator-electrode recorded CPR (prior to cannulation) and assessed the association between the longest CC pause duration and survival outcomes using multivariable logistic regression.

RESULTS

Of 49 E-CPR events, median age was 2.0 [Q1, Q3: 0.6, 6.6] years, 55% (27/49) survived to hospital discharge and 18/49 (37%) with favorable neurological outcome. Median duration of CPR was 51 [43, 69] min. During the last 5 min of recorded CPR prior to cannulation, median duration of the longest CC pause was 14.0 [6.3, 29.4] sec: 66% >10 sec, 25% >29 sec, 14% >60 sec, and longest pause 168 sec. Following planned adjustment for known confounders of age and CPR duration, each 5-sec increase in longest CC pause duration was associated with lower odds of survival to hospital discharge [adjusted OR 0.89, 95%CI: 0.79-0.99] and lower odds of survival with favorable neurological outcome [adjusted OR 0.77, 95%CI: 0.60-0.98].

CONCLUSIONS

Long CC pauses were common during the last 5 min of recorded CPR prior to E-CPR cannulation. Following adjustment for age and CPR duration, each 5-second incremental increase in longest CC pause duration was associated with significantly decreased rates of survival and favorable neurological outcome.

Longitudinal effect of high frequency training on CPR performance during simulated and actual pediatric cardiac arrest

Study aim

To determine the impact of high-frequency CPR training on performance during simulated and real pediatric CPR events in a pediatric emergency department (ED).

Methods

Prospective observational study. A high-frequency CPR training program (Resuscitation Quality Improvement (RQI)) was implemented among ED providers in a children's hospital. Data on CPR performance was collected longitundinally during quarterly retraining sessions; scores were analyzed between quarter 1 and quarter 4 by nonparametric methods. Data on CPR performance during actual patient events was collected by simultaneous combination of video review and compression monitor devices to allow measurement of CPR quality by individual providers; linear mixed effects models were used to analyze the association between RQI components and CPR quality.

Results

159 providers completed four consecutive RQI sessions. Scores for all CPR tasks during retraining sessions significantly improved during the study period. 28 actual CPR events were captured during the study period; 49 observations of RQI trained providers performing CPR on children were analyzed. A significant association was found between the number of prior RQI sessions and the percent of compressions meeting guidelines for rate (β coefficient -0.08; standard error 0.04; p = 0.03).

Conclusions

Over a 15 month period, RQI resulted in improved performance during training sessions for all skills. A significant association was found between number of sessions and adherence to compression rate guidelines during real patient events. Fewer than 30% of providers performed CPR on a patient during the study period. Multicenter studies over longer time periods should be undertaken to overcome the limitation of these rare events.

Factors affecting the course of resuscitation from cardiac arrest with pulseless electrical activity in children and adolescents

BACKGROUND

Although in-hospital pediatric cardiac arrests and cardiopulmonary resuscitation occur >15,000/year in the US, few studies have assessed which factors affect the course of resuscitation in these patients. We investigated transitions from Pulseless Electrical Activity (PEA) to Ventricular Fibrillation/pulseless Ventricular Tachycardia (VF/pVT), Return of Spontaneous Circulation (ROSC) and recurrences from ROSC to PEA in children and adolescents with in-hospital cardiac arrest.

METHODS

Episodes of cardiac arrest at the Children's Hospital of Philadelphia were prospectively registered. Defibrillators that recorded chest compression depth/rate and ventilation rate were applied. CPR variables, patient characteristics and etiology, and dynamic factors (e.g. the proportion of time spent in PEA or ROSC) were entered as time-varying covariates for the transition intensities under study.

RESULTS

In 67 episodes of CPR in 59 patients (median age 15 years) with cardiac arrest, there were 52 transitions from PEA to ROSC, 22 transitions from PEA to VF/pVT, and 23 recurrences of PEA from ROSC. Except for a nearly significant effect of mean compression depth beyond a threshold of 5.7 cm, only dynamic factors that evolved during CPR favored a transition from PEA to ROSC. The latter included a lower proportion of PEA over the last 5 min and a higher proportion of ROSC over the last 5 min. Factors associated with PEA to VF/pVT development were age, weight, the proportion spent in VF/pVT or PEA the last 5 min, and the general transition intensity, while PEA recurrence from ROSC only depended on the general transition intensity.

CONCLUSION

The clinical course during pediatric cardiac arrest was mainly influenced by dynamic factors associated with time in PEA and ROSC. Transitions from PEA to ROSC seemed to be favored by deeper compressions.

Performance of a Clinical Decision Support Tool to Identify PICU Patients at High Risk for Clinical Deterioration

OBJECTIVES

To evaluate the translation of a paper high-risk checklist for PICU patients at risk of clinical deterioration to an automated clinical decision support tool.

DESIGN

Retrospective, observational cohort study of an automated clinical decision support tool, the PICU Warning Tool, adapted from a paper checklist to predict clinical deterioration events in PICU patients within 24 hours.

SETTING

Two quaternary care medical-surgical PICUs-The Children's Hospital of Philadelphia and Cincinnati Children's Hospital Medical Center.

PATIENTS

The study included all patients admitted from July 1, 2014, to June 30, 2015, the year prior to the initiation of any focused situational awareness work at either institution.

INTERVENTIONS

We replicated the predictions of the real-time PICU Warning Tool by retrospectively querying the institutional data warehouse to identify all patients that would have flagged as high-risk by the PICU Warning Tool for their index deterioration.

MEASUREMENTS AND MAIN RESULTS

The primary exposure of interest was determination of high-risk status during PICU admission via the PICU Warning Tool. The primary outcome of interest was clinical deterioration event within 24 hours of a positive screen. The date and time of the deterioration event was used as the index time point. We evaluated the sensitivity, specificity, positive predictive value, and negative predictive value of the performance of the PICU Warning Tool. There were 6,233 patients evaluated with 233 clinical deterioration events experienced by 154 individual patients. The positive predictive value of the PICU Warning Tool was 7.1% with a number needed to screen of 14 patients for each index clinical deterioration event. The most predictive of the individual criteria were elevated lactic acidosis, high mean airway pressure, and profound acidosis.

CONCLUSIONS

Performance of a clinical decision support translation of a paper-based tool showed inferior test characteristics. Improved feasibility of identification of high-risk patients using automated tools must be balanced with performance.

Standardising communication to improve in-hospital cardiopulmonary resuscitation

AIM

Recommendations for standardised communication to reduce chest compression (CC) pauses are lacking. We aimed to achieve consensus and evaluate feasibility and efficacy using standardised communication during cardiopulmonary resuscitation (CPR) events.

METHODS

Modified Delphi consensus process to design standardised communication elements. Feasibility was pilot tested in 16 simulated CPR scenarios (8 scenarios with physician team leaders and 8 with chest compressors) randomized (1:1) to standardised [INTERVENTION] vs. closed-loop communication [CONTROL]. Adherence and efficacy (duration of CC pauses for defibrillation, intubation, rhythm check) was assessed by audiovisual recording. Mental demand and frustration were assessed by NASA task load index subscales.

RESULTS

Consensus elements for standardised communication included: 1) team preparation 15-30 s before CC interruption, 2) pre-interruption countdown synchronized with last 5 CCs, 3) specific action words for defibrillation, intubation, and interrupting/resuming CCs. Median (Q1,Q3) adherence to standardised phrases was 98% (80%,100%). Efficacy analysis showed a median [Q1,Q3] peri-shock pause of 5.1 s. [4.4; 5.8] vs. 7.5 s. [6.3; 8.8] seconds, p < 0.001, intubation pause of 3.8 s. [3.6; 5.0] vs. 6.9 s. [4.8; 10.1] seconds, p = 0.03, rhythm check pause of 4.2 [3.2,5.7] vs. 8.6 [5.0,10.5] seconds, p < 0.001, median frustration index of 10/100 [5,20] vs. 35/100 [25,50], p < 0.001, and median mental demand load of 55/100 [30,70] vs. 65/100 [50,85], p = 0.41 for standardised vs. closed loop communication.

CONCLUSION

This pilot study demonstrated feasibility of using consensus-based standardised communication that was associated with shorter CC pauses for defibrillation, intubation, and rhythm checks without increasing frustration index or mental demand compared to current best practice, closed loop communication.

First quantitative analysis of cardiopulmonary resuscitation quality during in-hospital cardiac arrests of young children

AIM

The objective of this study is to report, for the first time, quantitative data on CPR quality during the resuscitation of children under 8 years of age. We hypothesized that the CPR performed would often not achieve 2010 Pediatric Basic Life Support (BLS) Guidelines, but would improve with the addition of audiovisual feedback.

METHODS

Prospective observational cohort evaluating CPR quality during chest compression (CC) events in children between 1 and 8 years of age. CPR recording defibrillators collected CPR data (rate (CC/min), depth (mm), CC fraction (CCF), leaning (%>2.5 kg.)). Audiovisual feedback was according to 2010 Guidelines in a subset of patients. The primary outcome, "excellent CPR" was defined as a CC rate ≥ 100 and ≤ 120 CC/min, depth ≥ 50 mm, CCF >0.80, and <20% of CC with leaning.

RESULTS

8 CC events resulted in 285 thirty-second epochs of CPR (15,960 CCs). Percentage of epochs achieving targets was 54% (153/285) for rate, 19% (54/285) for depth, 88% (250/285) for CCF, 79% (226/285) for leaning, and 8% (24/285) for excellent CPR. The median percentage of epochs per event achieving targets increased with audiovisual feedback for rate [88 (IQR: 79, 94) vs. 39 (IQR 18, 62) %; p=0.043] and excellent CPR [28 (IQR: 7.2, 52) vs. 0 (IQR: 0, 1) %; p=0.018].

CONCLUSIONS

In-hospital pediatric CPR often does not meet 2010 Pediatric BLS Guidelines, but compliance is better when audiovisual feedback is provided to rescuers.

Pushing harder, pushing faster, minimizing interruptions… but falling short of 2010 cardiopulmonary resuscitation targets during in-hospital pediatric and adolescent resuscitation

AIM

The objective of this study was to evaluate the effect of instituting the 2010 Basic Life Support Guidelines on in-hospital pediatric and adolescent cardiopulmonary resuscitation (CPR) quality. We hypothesized that quality would improve, but that targets for chest compression (CC) depth would be difficult to achieve.

METHODS

Prospective in-hospital observational study comparing CPR quality 24 months before and after release of the 2010 Guidelines. CPR recording/feedback-enabled defibrillators collected CPR data (rate (CC/min), depth (mm), CC fraction (CCF, %), leaning (%>2.5kg)). Audiovisual feedback for depth was: 2005, ≥38mm; 2010, ≥50mm; for rate: 2005, ≥90 and ≤120CC/min; 2010, ≥100 and ≤120CC/min. The primary outcome was average event depth compared with Student's t-test.

RESULTS

45 CPR events (25 before; 20 after) occurred, resulting in 1336 thirty-second epochs (909 before; 427 after). Compared to 2005, average event depth (50±13mm vs. 43±9mm; p=0.047), rate (113±11CC/min vs. 104±8CC/min; p<0.01), and CCF (0.94 [0.93, 0.96] vs. 0.9 [0.85, 0.94]; p=0.013) increased during 2010. CPR epochs during the 2010 period more likely to meet Guidelines for CCF (OR 1.7; CI95: 1.2-2.4; p<0.01), but less likely for rate (OR 0.23; CI95: 0.12-0.44; p<0.01), and depth (OR 0.31; CI95: 0.12-0.86; p=0.024).

CONCLUSIONS

Institution of the 2010 Guidelines was associated with increased CC depth, rate, and CC fraction; yet, achieving 2010 targets for rate and depth was difficult.

Chest compression quality over time in pediatric resuscitations

BACKGROUND

Chest compression (CC) quality deteriorates with time in adults, possibly because of rescuer fatigue. Little data exist on compression quality in children or on work done to perform compressions in general. We hypothesized that compression quality, work, and rescuer fatigue would differ in child versus adult manikin models.

METHODS

This was a prospective randomized crossover study of 45 in-hospital rescuers performing 10 minutes of single-rescuer continuous compressions on each manikin. An accelerometer recorded compression quality measures over 30-second epochs. Work and power were calculated from recorded force data. A modified visual analogue scale measured fatigue. Data were analyzed by using linear mixed-effects models and Cox regression analysis.

RESULTS

A total of 88 484 compression cycles were analyzed. Percent adequate CCs/epoch (rate ≥ 100/minute, depth ≥ 38 mm) fell over 10 minutes (child: from 85.1% to 24.6%, adult: from 86.3% to 35.3%; P = .15) and were <70% in both by 2 minutes. Peak work per compression cycle was 13.1 J in the child and 14.3 J in the adult (P = .06; difference, 1.2 J; 95% confidence interval, -0.05 to 2.5). Peak power output was 144.1 W in the child and 166.5 W in the adult (P < .001; difference, 22.4 W, 95% confidence interval, 9.8-35.0).

CONCLUSIONS

CC quality deteriorates similarly in child and adult manikin models. Peak work per compression cycle is comparable in both. Peak power output is analogous to that generated during intense exercise such as running. CC providers should switch every 2 minutes as recommended by current guidelines.

Provider Adherence to Neonatal Resuscitation Program Recommendations for Coordinated Neonatal Chest Compressions and Ventilations

AIM

Medical providers often do not perform chest compressions in accordance with recommended resuscitation guidelines for adults and children. Little is known regarding how well neonatal providers perform coordinated chest compressions and ventilations. The objective of this study was to characterize Neonatal Resuscitation Program (NRP) trained providers' adherence to NRP recommendations for coordinated chest compressions and ventilations in a simulated setting.

METHODS

Fifty NRP providers performed coordinated chest compressions for three minutes on a neonatal manikin. A compression sensor (accelerometer) was used to monitor and record compression data. Data analyzed included ratio of compressions to ventilation pauses, delivered chest compressions per minute (CC/min), and duration of ventilation pauses.

RESULTS

Delivered CC/min ranged from 61 to 136. The mean CC/min (99, SD 16) was significantly higher than the NRP-recommended value of 90 (p=0.002). Delivered CC/min did not differ from the first 30 seconds to the last 30 seconds of compressions (p=0.91). Duration of ventilation pauses was highly correlated with CC/min (Spearman's rho= -0.98, p<0.001), with a median duration of 0.92 seconds (IQ range (0.84, 1.02).

CONCLUSIONS

NRP trained providers often do not adhere to NRP recommendations for delivery of coordinated chest compressions during simulated cardiac depression. The mean CC/min performed is higher than recommended. Duration of ventilation pauses is highly correlated with delivered CC/min. Future studies should focus on methods to improve the timing of delivered chest compressions by NRP providers to conform to NRP recommendations.

Ability of code leaders to recall CPR quality errors during the resuscitation of older children and adolescents

AIM

Performance of high quality CPR is associated with improved resuscitation outcomes. This study investigates code leader ability to recall CPR error during post-event interviews when CPR recording/audiovisual feedback-enabled defibrillators are deployed.

PATIENTS AND METHODS

Physician code leaders were interviewed within 24h of 44 in-hospital pediatric cardiac arrests to assess their ability to recall if CPR error occurred during the event. Actual CPR quality was assessed using quantitative recording/feedback-enabled defibrillators. CPR error was defined as an overall average event chest compression (CC) rate <95/min, depth < 38 mm, ventilation rate >10/min, or any interruptions in CPR >10s. We hypothesized that code leaders would recall error when it actually occurred ≥ 75% of the time when assisted by audiovisual alerts from a CPR recording feedback-enabled defibrillators (analysis by χ(2)).

RESULTS

810 min from 44 cardiac arrest events yielded 40 complete data sets (actual and interview); ventilation data was available in 24. Actual CPR error was present in 3/40 events for rate, 4/40 for depth, 32/40 for interruptions >10s, and 17/24 for ventilation frequency. In post-event interviews, code leaders recalled these errors in 0/3 (0%) for rate, 0/4 (0%) for depth, and 19/32 (59%) for interruptions >10s. Code leaders recalled these CPR quality errors less than 75% of the time for rate (p=0.06), for depth (p<0.01), and for CPR interruption (p=0.04). Quantification of errors not recalled: missed rate error median=94 CC/min (IQR 93-95), missed depth error median=36 mm (IQR 35.5-36.5), missed CPR interruption >10s median=18s (IQR 14.4-28.9). Code leaders did recall the presence of excessive ventilation in 16/17 (94%) of events (p=0.07).

CONCLUSION

Despite assistance by CPR recording/feedback-enabled defibrillators, pediatric code leaders fail to recall important CPR quality errors for CC rate, depth, and interruptions during post-cardiac arrest interviews.

The prevalence of chest compression leaning during in-hospital cardiopulmonary resuscitation

OBJECTIVE

Successful resuscitation from cardiac arrest requires the delivery of high-quality chest compressions, encompassing parameters such as adequate rate, depth, and full recoil between compressions. The lack of compression recoil ("leaning" or "incomplete recoil") has been shown to adversely affect hemodynamics in experimental arrest models, but the prevalence of leaning during actual resuscitation is poorly understood. We hypothesized that leaning varies across resuscitation events, possibly due to rescuer and/or patient characteristics and may worsen over time from rescuer fatigue during continuous chest compressions.

METHODS

This was an observational clinical cohort study at one academic medical center. Data were collected from adult in-hospital and Emergency Department arrest events using monitor/defibrillators that record chest compression characteristics and provide real-time feedback.

RESULTS

We analyzed 112,569 chest compressions from 108 arrest episodes from 5/2007 to 2/2009. Leaning was present in 98/108 (91%) cases; 12% of all compressions exhibited leaning. Leaning varied widely across cases: 41/108 (38%) of arrest episodes exhibited <5% leaning yet 20/108 (19%) demonstrated >20% compression leaning. When evaluating blocks of continuous compressions (>120 s), only 4/33 (12%) had an increase in leaning over time and 29/33 (88%) showed a decrease (p<0.001).

CONCLUSIONS

Chest compression leaning was common during resuscitation care and exhibited a wide distribution, with most leaning within a subset of resuscitations. Leaning decreased over time during continuous chest compression blocks, suggesting that either leaning may not be a function of rescuer fatiguing, or that it may have been mitigated by automated feedback provided during resuscitation episodes.

Low-dose, high-frequency CPR training improves skill retention of in-hospital pediatric providers

OBJECTIVE

To investigate the effectiveness of brief bedside cardiopulmonary resuscitation (CPR) training to improve the skill retention of hospital-based pediatric providers. We hypothesized that a low-dose, high-frequency training program (booster training) would improve CPR skill retention.

PATIENTS AND METHODS

CPR recording/feedback defibrillators were used to evaluate CPR quality during simulated arrest. Basic life support-certified, hospital-based providers were randomly assigned to 1 of 4 study arms: (1) instructor-only training; (2) automated defibrillator feedback only; (3) instructor training combined with automated feedback; and (4) control (no structured training). Each session (time: 0, 1, 3, and 6 months after training) consisted of a pretraining evaluation (60 seconds), booster training (120 seconds), and a posttraining evaluation (60 seconds). Excellent CPR was defined as chest compression (CC) depth ≥ one-third anterior-posterior chest depth, rate ≥90 and ≤120 CC per minute, ≤20% of CCs with incomplete release (>2500 g), and no flow fraction ≤ 0.30.

MEASUREMENTS AND MAIN RESULTS

Eighty-nine providers were randomly assigned; 74 (83%) completed all sessions. Retention of CPR skills was 2.3 times (95% confidence interval [CI]: 1.1-4.5; P=.02) more likely after 2 trainings and 2.9 times (95% CI: 1.4-6.2; P=.005) more likely after 3 trainings. The automated defibrillator feedback only group had lower retention rates compared with the instructor-only training group (odds ratio: 0.41 [95% CI: 0.17-0.97]; P = .043).

CONCLUSIONS

Brief bedside booster CPR training improves CPR skill retention. Our data reveal that instructor-led training improves retention compared with automated feedback training alone. Future studies should investigate whether bedside training improves CPR quality during actual pediatric arrests.

The first quantitative report of ventilation rate during in-hospital resuscitation of older children and adolescents

AIM

During adult cardiac arrest, rescuers frequently provide ventilations at rates exceeding those recommended by the American Heart Association (AHA). Excessive ventilation is associated with worse clinical outcome after adult cardiac arrest. This study is the first to characterize ventilation rate adherence to AHA guidelines during in-hospital pediatric cardiac arrest resuscitation.

PATIENTS AND METHODS

We prospectively enrolled children and adolescents (≥8 years of age) who suffered a cardiac arrest in a pediatric intensive care unit (PICU) or emergency department (ED) of a tertiary-care pediatric hospital. Ventilation rate (breaths per minute [bpm]) was monitored via changes in chest wall impedance (CWI) recorded by defibrillator electrode pads during cardiopulmonary resuscitation (CPR).

RESULTS

Twenty-four CPR events were enrolled yielding 588 thirty-second CPR epochs. The proportion of CPR epochs with ventilation rates exceeding AHA guidelines (>10 bpm) was 63% (CI(95) 59-67%), significantly higher than our a priori hypothesis of 30% (p<0.01). The proportion of CPR epochs with ventilation rates exceeding 20 bpm was 20% (CI(95) 17-23). After controlling for location of arrest and initial event rhythm, resuscitations that occurred on nights/weekends were 3.6 times (CI(95): 1.6-7.9, p<0.01) more likely to have a ventilation rate exceeding AHA guidelines.

CONCLUSIONS

During in-hospital pediatric cardiac arrest, rescuers frequently provide artificial ventilations at rates in excess of AHA guidelines, with twenty percent of CPR time having ventilation rates double that recommended. Excessive ventilation was particularly common during CPR events that occurred on nights/weekends.

Effect of residual leaning force on intrathoracic pressure during mechanical ventilation in children

AIM

Determine the effect of residual leaning force on intrathoracic pressure (ITP) in healthy children receiving mechanical ventilation. We hypothesized that application of significant residual leaning force (2.5kg or 20% of subject body weight) would be associated with a clinically important change in ITP.

METHODS

IRB-approved pilot study of healthy, anesthetized, paralyzed mechanically ventilated children (6 months to 7 years). Peak endotracheal pressure (ETP), a surrogate of ITP, was continuously measured before and during serial incremental increases in sternal force from 10% to 25% of the subject's body weight. A delta ETP of >or=2.0cmH(2)O was considered clinically significant.

RESULTS

13 healthy, anesthetized, paralyzed mechanically ventilated children (age: 26+/-24m, range: 6.5-87m; weight: 13+/-5kg, range: 7.4-24.8kg) were enrolled. Peak ETP increased from baseline for all force applications (10% body weight: mean difference of 0.8cmH(2)O, p<0.01; 15% body weight: mean difference of 1.1cmH(2)O, p<0.01; 20% body weight: mean difference of 1.5cmH(2)O, p<0.01; 25% body weight: mean difference of 1.89cmH(2)O, p<0.01). Residual leaning force of >or=2.5kg was associated with a 2.0cmH(2)O change in peak ETP (odds ratio 7.5; CI(95) 1.5-37.7; p=0.014) while sternal force >or=20% body weight was not (odds ratio 2.4; CI(95) 0.6-9.2; p=0.2).

CONCLUSION

In healthy anesthetized children, changes in ETP were detectable at residual leaning forces as low as 10% of subject body weight. Residual leaning force of 2.5kg was associated with increases in ETP >or=2.0cmH(2)O.

Expert clinical assessment of thorax stiffness of infants and children during chest compressions

BACKGROUND

High-fidelity manikins have been shown to be useful in teaching appropriate cardiopulmonary resuscitation (CPR) techniques. Similarity of manikin chest compression characteristics to real children is desirable. Little data exists on thorax stiffness in infants and children to guide manikin construction.

OBJECTIVE

To determine a 'consensus clinical-expert assessment' of the pediatric chest stiffness for two specific age groups-infants and 5-year-olds.

METHODS

Four manikins in each of two sizes (5-year child, 6-month infant) were identically constructed, except for thorax downstroke spring stiffness. Health care providers with pediatric CPR experience provided chest compressions to each manikin in random order, masked to thoracic stiffness. Each health care provider was instructed to identify the manikin with downstroke thoracic stiffness most similar to children on whom they have performed chest compressions. Duplicate assessment of a randomly selected, previously assessed manikin was performed to assess health care provider consistency using the kappa statistic. Subject inter-rater agreement on which manikin best approximated a child of that age was assessed by calculating the percentage of subjects who identified that manikin as the best approximation of an actual child.

RESULTS

A convenience sample of 63 international experts was obtained: 52 from Critical Care, 3 from Emergency Medicine, 4 from Pediatrics, and 4 from other specialties. There were 6 and 8 experts whose assessments were inconsistent for the infant manikins and child manikins, respectively. Approximately half of the subjects agreed on a single manikin as the best approximation of the human for both the infant (46%) and child manikins (43%). Excluding assessments of stiffness "out of range", the percentage of experts who agreed on a single manikin as the best approximation for the human increased to approximately 90% for each manikin size.

CONCLUSION

Experienced health care providers consistently identified and agreed on the manikin thorax stiffness which they felt best approximated downstroke chest compression stiffness of children and infants. Expert opinion can be used to create manikins with realistic spring stiffness for CPR training. Further study is needed to evaluate whether enhanced manikin biofidelity will improve CPR performance.

Quantitative analysis of CPR quality during in-hospital resuscitation of older children and adolescents

OBJECTIVE

Few data exist on pediatric cardiopulmonary resuscitation (CPR) quality. This study is the first to evaluate actual in-hospital pediatric CPR. We hypothesized that with bedside CPR training and corrective feedback, CPR quality can approach American Heart Association (AHA) targets.

PATIENTS AND METHODS

Using CPR recording/feedback defibrillators, quality of CPR was assessed for patients >or=8 years of age who suffered a cardiac arrest in the PICU or emergency department (ED). Before and during the study, a bedside CPR training program was initiated.

RESULTS

Between October 2006 and February 2008, twenty events in 18 patients met inclusion criteria and resulted in 36749 evaluable chest compressions (CCs) during 392.3 minutes of arrest. CCs were shallow (<38 mm or <1.5 in) in 27.2% (9998 of 36749), with excessive residual leaning force (>or=2500 g) in 23.4% (8611 of 36749). Segmental analysis of the first 5 minutes of the events demonstrated that shallow CCs and excessive residual leaning force were less prevalent during the first 5 minutes. AHA targets were not achieved for CC rate in 62 (43.1%) of 144 segments, CC depth in 52 (36.1%) of 144 segments, and residual leaning force in 53 (36.8%) of 144 segments.

CONCLUSIONS

This prospective, observational study demonstrates feasibility of monitoring in-hospital pediatric CPR. Even with bedside CPR retraining and corrective audiovisual feedback, CPR quality frequently did not meet AHA targets. Importantly, no flow fraction target of 10% was achieved. Future studies should investigate novel educational methods and targeted feedback technologies.

Pediatric CPR quality monitoring: analysis of thoracic anthropometric data

INTRODUCTION

Quantitative CPR quality feedback systems improve adult CPR performance. Extension to pediatric patients is desirable; however, the anthropometric measurements of the pediatric chest pertinent to guide the development of pediatric-specific CPR monitoring systems are largely unknown.

HYPOTHESIS

Adult-based CPR quality monitoring and feedback systems will require pediatric-specific tailoring and adaptation.

METHODS

Anthropometric measurements pertinent to the development of pediatric-specific CPR quality monitoring systems were obtained in 150 children ages 6 months to 8 years. Standard descriptive statistics were calculated. Absolute depth point estimates and 95% confidence intervals were calculated for the American Heart Association (AHA) chest compression depth recommendations (1/3 and 1/2 Anterior-Posterior chest depth). Percentage of subjects for which the adult minimal feedback depth of 38mm would coach to achieve pediatric AHA target depths was determined.

RESULTS

Point estimate averages for measurements pertinent to pediatric adaptation of CPR monitoring technology were: sternal width: 25.1mm [22.0-29.2]; sternal length: 98.7mm [95.3-102.1]; internipple distance: 120.0mm [117.2-122.8]; chin to sternal notch: 35.3mm [31.2-39.4]; 1/3 AP chest depth: 37.0mm [36.1-37.8]; and 1/2 AP chest depth: 55.4mm [54.2-56.7]. A minimal feedback depth of 38mm would meet the minimum pediatric AHA target for depth in 55% (82/148) of subjects, and coach too deep in only 2% (3/148).

CONCLUSION

Extension of adult-based CPR quality monitoring and feedback systems will require pediatric-specific tailoring and adaptation. Future studies should examine chest compression depths in clinical settings with correlation to physiologic parameters to determine the best targets for pediatric CPR guidelines.

Estimation of optimal CPR chest compression depth in children by using computer tomography

OBJECTIVE

Pediatric consensus-driven cardiopulmonary resuscitation guidelines target chest compression (CC) depths of one third to one half anterior-posterior (AP) chest depth. Estimates for this target as assessed by computed tomography (CT) measurements of internal and external AP chest dimensions could direct future pediatric cardiopulmonary resuscitation guidelines.

METHODS

A total of 280 consecutive chest CT scans in permuted blocks of 20 for each of 14 age divisions between 0 and 8 years were reconstructed and analyzed. External and internal AP depths were measured at midsternum, and residual chest depth was calculated at simulated one-third and one-half AP compressions.

RESULTS

After a simulated compression calculation, one-half external AP depth CC would result in residual internal depth of <10 mm for 94% (263 of 280) of children 3 months to 8 years. For a one-third external AP CC, only 0.4% (1 of 280) of children 3 months to 8 years had a calculated residual internal chest depth <10 mm.

CONCLUSIONS

By using CT reconstruction estimates of chest dimensions across the developmental spectrum from 0 to 8 years of age, we demonstrated that a simulated CC targeting approximately one-third external AP chest depth seems radiographically appropriate for children aged 3 months to 8 years, whereas simulated CC targeting approximately one-half external AP chest depth seems radiographically to be too deep, resulting in residual internal chest depth of <10 mm for most patients of this age.

"Rolling Refreshers": a novel approach to maintain CPR psychomotor skill competence

OBJECTIVES

High quality CPR skill retention is poor. We hypothesized that "just-in-time" and "just-in-place" training programs would be effective and well-accepted to maintain CPR skills among PICU staff.

METHODS

"Rolling Refreshers", a portable manikin/defibrillator system with chest compression sensor providing automated corrective feedback to optimize CPR skills, were conducted daily in the PICU with multidisciplinary healthcare providers. Providers practiced CPR until skill success was attained, prospectively defined as <3 corrective prompts within 30s targeting chest compression (CC) rate 90-120/min, CC depth > 38 mm during continuous CPR. Providers completing > or =2 refreshers/month (Frequent Refreshers [FR]) were compared to providers completing < 2 refreshers/month (Infrequent Refreshers [IR]) for time to achieve CPR skill success. Univariate analysis performed using non-parametric methods. Following actual cardiac arrests, CPR providers were surveyed for subjective feedback on training approach efficacy (5-point Likert scale; 1=poor to 5=excellent).

RESULTS

Over 15 weeks, 420 PICU staff were "refreshed": 340 nurses, 34 physicians, 46 respiratory therapists. A consecutive sample of 20 PICU staff was assessed before subsequent refresher sessions (FREQ n=10, INFREQ n=10). Time to achieve CPR skill success was significantly less in FREQ (median 21s, IQR: 15.75-30s) than in INFREQ (median 67s, IQR: 41.5-84s; p<0.001). Following actual resuscitations, CPR providers (n=9) rated "Rolling Refresher" training as effective (mean=4.2; Likert scale 1-5; standard deviation 0.67).

CONCLUSIONS

A novel "Rolling Refresher" CPR skill training approach using "just-in-time" and "just-in-place" simulation is effective and well received by PICU staff. More frequent refreshers resulted in significantly shorter times to achieve proficient CPR skills.

Methods for determining pediatric thoracic force-deflection characteristics from cardiopulmonary resuscitation

Accurate pediatric thoracic force and deflection data are critical to develop biofidelic pediatric anthropomorphic test devices (ATDs) used in designing motor vehicle safety systems for child occupants. Typically, post-mortem human subject (PMHS) experiments are conducted to gather such data. However, there are few pediatric PMHS available for impact research, therefore novel methods are required to determine pediatric biomechanical data from children. In this study, we have leveraged the application of chest compressions provided in the clinical environment during pediatric cardiopulmonary resuscitation (CPR) to collect this fundamental data. The maximum deflection of the chest during CPR is in the range of chest deflections in PMHS impact experiments and therefore CPR exercises the chest in ways that are meaningful for biofidelity assessment. Thus, the goal of this study was to measure the force-deflection characteristics of the thorax of children and young adults during CPR. To do so, a force and deflection sensor was integrated into a patient monitor-defibrillator used during CPR in the Pediatric Intensive Care Unit and Emergency Department of a children's hospital. The sensor was interposed between the chest of the patient and hands of the rescuer during CPR compressions. Following a CPR event, thoracic force and deflection data were downloaded from the monitor-defibrillator for analysis. Each compression cycle was fit to a parallel spring-damper model, wherein stiffness and damping were linearly dependent on chest deflection. Average maximum chest deflection, force at maximum deflection, linear stiffness, and elastic and viscous model forces are reported for each subject and correlated with age. Eighteen subjects (11 females) ages 8 to 22 years were enrolled in the study and each received a mean of 2000 (Standard Deviation 2339) chest compressions during CPR. Average maximum chest deflection and corresponding force were 39 +/- 5 mm and 309 +/- 55 N respectively. When combined with our previous study of adult CPR data, and other data from the literature, our findings suggest that the stiffness of the thorax increases from youth to middle age, and then decreases in the elderly. CPR has the potential to provide data from a wide range of human subjects with which to study the effect of age on mechanics of thoracic deformation. Future studies will expand the sample size and age range of data collected to further explore the age-related changes in thoracic mechanics.

Bilateral coordination in human infants: stepping on a split-belt treadmill

A motorized treadmill often elicits locomotor-like alternate stepping in 7-month-old infants who normally perform few, if any, stepping movements. The step cycle duration is a function of the speed of the treadmill. When infants were held so that each leg was on a separate treadmill belt, each of which was driven at a different speed, the overall cycle duration was intermediate between the cycle durations at the fast or slow speeds alone. Infants shortened the stance on the slow belt and increased the stance on the fast belt to maintain regularly alternating steps. Even before voluntary locomotion, both legs acted in a cooperative manner, with the dynamic status of one limb affecting the timespace behavior of the opposite limb.

Bilateral coordination in human infants: Stepping on a split-belt treadmill

A motorized treadmill often elicits locomotor-like alternate stepping in 7-month-old infants who normally perform few, if any, stepping movements. The step cycle duration is a function of the speed of the treadmill. When infants were held so that each leg was on a separate treadmill belt, each of which was driven at a different speed, the overall cycle duration was intermediate between the cycle durations at the fast or slow speeds alone. Infants shortened the stance on the slow belt and increased the stance on the fast belt to maintain regularly alternating steps. Even before voluntary locomotion, both legs acted in a cooperative manner, with the dynamic status of one limb affecting the timespace behavior of the opposite limb.