Physical activity levels, pulmonary function, and MRI in children born extremely preterm: A comparison between children with and without bronchopulmonary dysplasia.

INTRODUCTION: Children with a history of bronchopulmonary dysplasia (BPD) may have lower physical activity levels, but evidence to date is mixed. This study compared physical activity levels between children born extremely preterm with and without history of BPD, and examined their associations with pulmonary magnetic resonance imaging (MRI) and pulmonary function test (PFT) indices. METHODS: This multicentre cross-sectional study included children aged 7-9 years born extremely preterm, with and without BPD. Children wore a pedometer for 1 week, then completed the Physical Activity Questionnaire (PAQ), pulmonary MRI, and PFT. Spearman correlations and multivariable linear regression modeling were performed. RESULTS: Of 45 children, 28 had a history of moderate-severe BPD. There were no differences in any physical activity outcomes by BPD status. Higher average daily step count and higher average daily moderate-to-vigorous physical activity (MVPA) were each correlated with greater forced vital capacity (r = 0.41 and 0.58), greater MRI lung proton density at full expiration (r = 0.42 and 0.49), and lower lung clearance index (r = -0.50 and -0.41). After adjusting for MRI total proton density and BPD status, a 5% increase in forced expiratory volume at 1 s was associated with 738 (95% CI: 208, 1268) more steps per day and 0.1 (0.0, 0.2) more hours of MVPA, respectively. CONCLUSION: School-aged children born extremely preterm have similar physical activity levels to their peers, regardless of history of BPD. MRI and PFT measures suggestive of gas trapping and/or airflow obstruction are associated with lower physical activity levels.

A randomized, cross-over trial comparing the effect of innovative robotic gait training and functional clinical therapy in children with cerebral palsy; a protocol to test feasibility.

PURPOSE: Robotic gait training is relatively new in the world of pediatric rehabilitation. Preliminary feasibility studies and case reports include stationary robot-assisted treadmill training. Mobile robotic gait trainers hold greater promise for intensive practice-based therapy within hospitals, schools, rehabilitation centers, and at-home therapy as they enable participation and social integration while practicing high-quality gait patterns. MATERIALS AND METHODS: This paper (clinical trials registry number: NCT05378243) provides a detailed description of a mixed-method cross-over trial design with a broad set of outcome measures. Ultimately the goal is to establish the feasibility of this design which includes the collection of qualitative data regarding patient, family, and therapist experience and quantitative data regarding gait efficiency and quality, impact on tone, individualized goal achievement and bone strength.

Sleep-disordered breathing symptoms and their association with structural and functional pulmonary changes in children born extremely preterm.

This study aimed to evaluate symptoms of sleep-disordered breathing (SDB) among children born extremely preterm, with and without a history of bronchopulmonary dysplasia (BPD), including associations between sleep and respiratory symptoms, physical activity, pulmonary function, and pulmonary magnetic resonance imaging (MRI). This multi-center cross-sectional study enrolled children aged 7-9 years born extremely preterm with and without BPD. Participants completed the Pediatric Sleep Questionnaire (PSQ), the modified Epworth sleepiness scale, a respiratory symptom questionnaire, pedometer measurements, pulmonary function testing, and pulmonary MRI. Spearman's correlations and univariate and multivariable linear regression modelling were performed. Twenty-eight of 45 children included had a history of moderate-to-severe BPD. The prevalence of sleep-related symptoms was low, with the exception of hyperactivity and inattention. There were no differences in mean (SD) scores on sleep questionnaires in children with and without BPD (PSQ: 0.21 (0.13) vs 0.16 (0.14), p = 0.3; modified Epworth: 2.4 (2.4) vs 1.8 (2.8), p = 0.4). Multiple regression analyses examining difference in sleep scores between groups, adjusting for gestational age and intraventricular hemorrhage, found no statistical difference (p > 0.05). Greater daytime sleepiness was moderately correlated with FEV1%-predicted (r = - 0.52); no other moderate-strong associations were identified.  Conclusions: There was no evidence of clinically important differences in sleep symptoms between children with and without BPD, suggesting that sleep symptoms may be related to prematurity-related factors other than a BPD diagnosis, including airflow limitation. Further research is necessary to explore the relationship between sleep symptoms, airway obstruction, and neurobehavioral symptoms among premature-born children.  Trial registration: NCT02921308. Date of registration: October 3, 2016. What is Known: • Presence of bronchopulmonary dysplasia (BPD) may further contribute to the development of SDB, though its impact is not well-studied. • Premature-born children have a greater risk of lung structural and functional differences, including sleep-disordered breathing (SDB). What is New: • There was no difference in sleep symptoms between children with and without BPD, suggesting that sleep symptoms are related to other prematurity-related factors, such as airflow limitation. • Greater daytime sleepiness was correlated with lower FEV1 in our population, which reflects greater airflow limitation.

Behavioral and emotional characteristics of Canadian children with obesity and moderate-severe sleep-disordered breathing treated with positive airway pressure: longitudinal changes and associations with adherence.

STUDY OBJECTIVES: Behavioral characteristics and outcomes of positive airway pressure (PAP) therapy in children with obesity and moderate-severe sleep-disordered breathing (SDB) have not been reported. Our aims were to 1) determine baseline behavioral/emotional symptoms of this population and characterize changes over time with PAP, and 2) examine associations between baseline behavioral/emotional symptoms and PAP adherence. METHODS: This multicenter prospective cohort study of children with obesity prescribed PAP for moderate-severe SDB assessed PAP adherence (≥ 4 h/night, >50% of nights, usage diaries, downloads) and compared behavioral/emotional characteristics with parent- and child-reported Conners Rating Scale (Conners) and the Child Behavior Checklist (CBCL) at baseline and 1 year after PAP prescription between adherent and nonadherent participants; scores at baseline were compared retrospectively between adherence groups. RESULTS: Twenty-four children were included (median 14.1 years [IQR:12.4,16.0]; 87.5% males). Baseline Conners and CBCL scores were elevated (parent- and child-reported Conners inattention and hyperactivity subscales and CBCL subscales [total, internalizing, externalizing]). Baseline parent-reported Conners scores were significantly more elevated in the nonadherent than adherent group (inattention: 73.3 ± 8.5 vs 60.5 ± 14.6, P = .01; hyperactivity: 70.9 ± 11.1 vs 59.1 ± 16.0, P = .05). This difference was present 1 year later for inattention (P = .01) but not for hyperactivity (P = .09). Parent-reported CBCL scores improved over 1 year in adherent but not nonadherent participants. CONCLUSIONS: We found that children with obesity and moderate-severe SDB have elevated symptoms of behavioral/emotional concerns on standardized testing. Parent-reported emotional characteristics improved in the adherent but not in the nonadherent group. Children with greater inattention/hyperactivity at baseline were less adherent to PAP, suggesting this may contribute to PAP nonadherence. CITATION: Constantin E, MacLean JE, Barrowman N, et al. Behavioral and emotional characteristics of Canadian children with obesity and moderate-severe sleep-disordered breathing treated with positive airway pressure: longitudinal changes and associations with adherence. J Clin Sleep Med. 2023;19(3):555-562.

Opioid dose and postoperative respiratory adverse events after adenotonsillectomy in medically complex children.

STUDY OBJECTIVES: Obstructive sleep-disordered breathing is commonly treated with adenotonsillectomy. Our study objective was to describe perioperative opioid dosing in children with a range of medical complexity evaluated for obstructive sleep-disordered breathing undergoing adenotonsillectomy and to investigate its association with postoperative respiratory adverse events (PRAEs). METHODS: A retrospective chart review of children who underwent adenotonsillectomy and had preoperative polysomnography performed was conducted. PRAEs included requiring oxygen, jaw thrust, positive airway pressure, or mechanical ventilation. Multivariable logistic regression was performed to examine for associations between covariates and PRAEs. RESULTS: The cohort included 374 children with obstructive sleep-disordered breathing, median (interquartile range) age 6.1 (3.9, 9.3) years; 344 (92%) had obstructive sleep apnea (apnea-hypopnea index > 1 events/h) while 30 (8%) had a normal polysomnogram (apnea-hypopnea index < 1 events/h). The median (interquartile range) postoperative morphine-equivalent dose administered was 0.17 (0.09, 0.25) mg/kg. Sixty-six (17.6%) experienced at least 1 PRAE. Multivariable modeling identified the following predictors of PRAE: younger age at surgery (odds ratio 0.90, 95% confidence interval 0.83, 0.98), presence of cardiac comorbidity (odds ratio 2.07, 95% confidence interval 1.09, 3.89), and presence of airway anomaly (odds ratio 3.48, 95% confidence interval 1.30, 8.94). Higher total apnea-hypopnea index and morphine-equivalent dose were associated with PRAE risk, and an interaction between these variables was detected (P = .01). CONCLUSIONS: This study identified opioid dose in morphine equivalents to be a strong predictor of PRAE. Additionally, severity of obstructive sleep apnea and postoperative morphine-equivalent dose contributed together and independently to the occurrence of PRAEs. Attention to opioid dosing, particularly among medically complex children with obstructive sleep-disordered breathing, is required to mitigate risk of PRAEs. CITATION: Tsampalieros A, Murto K, Barrowman N, et al. Opioid dose and postoperative respiratory adverse events after adenotonsillectomy in medically complex children. J Clin Sleep Med. 2022;18(10):2405-2413.

Risk factors for respiratory adverse events after adenoidectomy and tonsillectomy in children with down syndrome: a retrospective cohort study.

Obstructive sleep apnea syndrome is a major cause of morbidity in the Down syndrome population and is commonly treated with adenoidectomy and/or tonsillectomy (AT). However, these children are at increased risk for perioperative respiratory adverse events (PRAEs). The objective of this study was to examine risk factors for major PRAEs requiring intervention in children with Down syndrome undergoing AT and to describe their postoperative monitoring environment. This retrospective study included all children with Down syndrome aged 0-18 years who underwent a preoperative polysomnogram followed by AT at a tertiary pediatric institution. Descriptive statistics were used to summarize baseline demographic and clinical characteristics. A multivariable model for prediction of PRAEs was constructed. A priori, it was decided that minimum oxygen saturation, apnea-hypopnea index, and average oxygen saturation asleep would be included, along with medical comorbidities associated with PRAEs at p < 0.2 in univariable analyses. Fifty-eight children were included in this study; twelve had a PRAE. Cardiac disease was associated with PRAEs on univariable analysis (p = 0.03). In multivariable analysis, average oxygen saturation asleep was associated with PRAEs (OR 1.50; 95% confidence interval 1.00, 2.41; p = 0.05). For all of the remaining variables, p > 0.15. Fifty-six children were admitted for monitoring overnight; four were admitted to the intensive care unit and fifty-two were admitted to the ward. CONCLUSIONS: A multivariable model found evidence that lower average oxygen saturation while asleep was associated with PRAEs requiring intervention in children with Down syndrome. This study highlights the difficulty in predicting complications in this population. WHAT IS KNOWN: • Obstructive sleep apnea syndrome is a major cause of morbidity in the Down syndrome population and is commonly treated with adenoidectomy and/or tonsillectomy. • However, children with Down syndrome are at increased risk for perioperative respiratory adverse events (PRAEs) following adenoidectomy and/or tonsillectomy. WHAT IS NEW: • We found that a lower average oxygen saturation asleep is associated with increased odds of PRAEs, adjusting for age, total apnea-hypopnea index, cardiac comorbidity, and minimum oxygen saturation. • This study highlights the difficulty in predicting complications in this population.

Pulmonary Magnetic Resonance Imaging of Ex-Preterm Children with and without Bronchopulmonary Dysplasia.

Rationale: Children born prematurely, particularly those with bronchopulmonary dysplasia, have persisting lung abnormalities requiring longitudinal monitoring. Pulmonary ultrashort echo time magnetic resonance imaging (MRI) measurements may provide sensitive markers of persisting lung abnormalities and have not been evaluated in school-aged children born prematurely. Objectives: To compare pulmonary MRI and pulmonary function test measurements in preterm-born school-aged children with and without bronchopulmonary dysplasia. Methods: Children aged 7-9 years, born extremely preterm, with and without bronchopulmonary dysplasia, were recruited from three centers. Participants underwent pulmonary ultrashort echo time MRI and pulmonary function tests. Primary outcomes included total proton density and proton density at full expiration, measured using MRI. Multiple linear regression analysis was performed, adjusting for gestational age and bronchopulmonary dysplasia. Associations between MRI and pulmonary function were tested. Results: Thirty-five children were included in the primary analysis (24 with bronchopulmonary dysplasia, 11 without); 29 completed pulmonary function tests, of whom 11 (38%) had airflow limitation. Children with bronchopulmonary dysplasia had 44% (95% confidence interval [CI], 10-66%) lower mean total proton density (mean ± standard deviation, 3.6 ± 2.6) than those without (6.1 ± 4.0). Those with bronchopulmonary dysplasia had 25% (95% CI, 3-42%) lower proton density at full expiration than those without. Lower total proton density and proton density at full expiration were moderately correlated with greater residual volume, residual volume/total lung capacity, and lung clearance index (Spearman correlations for total proton density: -0.42, -0.57, and -0.53, respectively. Spearman correlations for proton density at full expiration: -0.28, -0.57, and -0.45, respectively). Conclusions: School-aged preterm-born children with bronchopulmonary dysplasia have parenchymal tissue abnormalities measured using ultrashort MRI proton density, compared with those without. MRI proton density correlated with pulmonary function measures indicative of gas trapping. Clinical trial registered with www.clinicaltrials.gov (NCT02921308).

Polysomnography parameters as predictors of respiratory adverse events following adenotonsillectomy in children.

STUDY OBJECTIVES: The first-line treatment of obstructive sleep apnea syndrome in children is adenotonsillectomy, but this may result in perioperative respiratory adverse events (PRAEs). The primary aim of this study is to examine whether the McGill oximetry score (MOS) and other polysomnography parameters can predict major PRAEs following adenotonsillectomy. We secondarily evaluated the MOS interrater reliability and correlation with other polysomnography parameters. METHODS: This retrospective study included all children aged 0-18 years who underwent preoperative polysomnography between June 2010 and January 2016 prior to adenotonsillectomy at a tertiary pediatric institution. Oximetries from polysomnograms were assigned an MOS. Univariable and multivariable models for prediction of major PRAEs were constructed. MOS was correlated with polysomnography parameters and interrater reliability was evaluated. RESULTS: This study included 106 children; 15 had a major PRAE. A multivariable prediction model that combined MOS and age showed evidence for the ability to predict major PRAEs with an area under the receiver operating characteristic curve of 0.68 (95% confidence interval: 0.52, 0.84), whereby increased MOS and younger age were associated with PRAEs, but apnea-hypopnea index was not. MOS had excellent interrater reliability (κ = 0.95) and was highly correlated with oxygen saturation nadir and cumulative time percentage with oxygen saturation less than 90%. CONCLUSIONS: A prediction model including MOS and age may predict PRAEs following adenotonsillectomy. This suggests that nocturnal oximetry provides the most essential information of polysomnography measures to direct postoperative monitoring following adenotonsillectomy. CITATION: Xiao L, Barrowman N, Momoli F, et al. Polysomnography parameters as predictors of respiratory adverse events following adenotonsillectomy in children. J Clin Sleep Med. 2021;17(11):2215-2223.

Effect of oxygen saturation targets on the incidence of bronchopulmonary dysplasia and duration of respiratory supports in extremely preterm infants.

BACKGROUND: Recent clinical practice changes in neonatal care resulted in higher, narrower oxygen saturation target ranges for preterm infants. The effect of targeting higher or lower oxygen saturations on respiratory outcomes of preterm infants and duration of hospitalization has not been extensively reviewed in the context of current care, but could have significant implications. METHODS: A multicentre retrospective cohort of 145 preterm infants was conducted; 105 had lower oxygen saturation targets (88 to 92%), 40 had higher targets (90 to 95%). The primary outcome was bronchopulmonary dysplasia (BPD). Secondary outcomes included duration of invasive/noninvasive respiratory support, oxygen therapy, and hospitalization. The primary outcome was compared using Fisher's exact test. Secondary outcomes were evaluated with survival analysis and Wilcoxon rank sum test. RESULTS: The difference in incidence of BPD in the lower (N=56, 53.3%) and higher saturation groups (N=14, 35.0%) was not statistically significant (relative risk [RR]=0.66 [0.41, 1.04], P=0.06). The difference in duration of mechanical ventilation in the lower (median 7.8 days, interquartile range [IQR] 3.7 to 15.9) and higher saturation groups (median 4.5, IQR 1.9 to 12.3) approached statistical significance (P=0.05). There were no statistically significant differences in the durations of other respiratory supports or hospital stay between the two groups. CONCLUSIONS: The results of this study approached statistical significance and suggest that higher, narrower oxygen saturation targets may result in a clinically important reduction in BPD incidence and duration of mechanical ventilation. These results require validation in a larger sample to refine optimal targets.

Predictors of postoperative respiratory complications in children undergoing adenotonsillectomy.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is commonly treated with adenotonsillectomy (AT), bringing risk of perioperative respiratory adverse events (PRAEs). We aimed to concurrently identify clinical and polysomnographic predictors of PRAEs in children undergoing AT. METHODS: Retrospective study of children undergoing AT at a tertiary-care pediatric hospital, with prior in-hospital polysomnography, January 2010 to December 2016. PRAEs included those requiring oxygen, jaw thrust, positive airway pressure, or mechanical ventilation. Relationships of PRAEs to preoperative comorbidities or polysomnography results were examined with univariable logistic regression. Variables with P < .1 and age were included in backward stepwise multivariable logistic regression. Predictive performance (area under the curve, AUC) was validated with bootstrap resampling. RESULTS: Analysis included 374 children, median age 6.1 years; 286 (76.5%) had ≥ 1 comorbidity. 344 (92.0%) had sleep-disordered breathing; 232 (62.0%) moderate-severe; 66 (17.6%) had ≥ 1 PRAE. PRAEs were more frequent in children with craniofacial, genetic, cardiac, airway anomaly, or neurological conditions, AHI ≥ 5 events/h and oxygen saturation nadir ≤ 80% on preoperative polysomnography. Prediction modeling identified cardiac comorbidity (odds ratio [OR] 2.09 [1.11, 3.89]), airway anomaly (OR 3.19 [1.33, 7.49]), and younger age (OR < 3 years: 4.10 (1.79, 9.26; 3 to 6 years: 2.21 [1.18, 4.15]) were associated with PRAEs (AUC 0.74; corrected AUC 0.68). CONCLUSIONS: Prediction modeling concurrently evaluating comorbidities and polysomnography metrics identified cardiac disease, airway anomaly, and young age as independent predictors of PRAEs. These findings suggest that medical comorbidity and age are more important factors in predicting PRAEs than PSG metrics in a medically complex population.

Treatment and persistence/recurrence of sleep-disordered breathing in children with Down syndrome.

OBJECTIVE: Sleep-disordered breathing (SDB) is common in children with Down syndrome, but the trajectory and long-term outcomes are not well-described. In a retrospective longitudinal cohort of children with Down syndrome, study objectives were to (1) characterize polysomnography (PSG), treatments received, and persistence/recurrence of SDB and (2) explore predictors of SDB persistence/recurrence. METHODS: A retrospective cohort study was conducted of children who underwent PSGs between 2004 and 2014. SDB was defined as obstructive sleep apnea (OSA)-mixed (apnea-hypopnea index [AHI] >5 events/hour), central sleep apnea or hypoventilation. PSGs, interventions, and trajectory of SDB were described. Age, body mass index (BMI) Z-score and AHI at first SDB diagnosis were evaluated as predictors of persistent/recurrent SDB. RESULTS: Of 506 children, 120 had ≥1 PSG; 54 had subsequent PSGs. Children with ≥2 PSGs were more likely to have higher total AHI (P = .02) and obstructive-mixed AHI (P = .01). Thirty-five of fifty-four (65%) were initially diagnosed with OSA-mixed SDB. After first PSG, 67 of 120 had OSA-mixed SDB, of whom 25 (37.3%) underwent adenotonsillectomy (T&A), 13 (19.4%) received positive airway pressure (PAP). Those who underwent T&A after PSG were significantly younger than those who received PAP (median age 6.2 vs 12.5 years; P = .005). OSA-mixed SDB persisted/recurred in 33 of 54 (73.3%) with ≥2 PSGs. Persistence/recurrence was not associated with age, AHI or BMI Z-score at first SDB. CONCLUSION: Children with Down syndrome undergoing T&A for SDB were significantly younger than those treated with PAP. SDB persisted/recurred in three of four and was not predicted by age, SDB severity or BMI Z-score. Longitudinal PSG assessment for persistence/recurrence of SDB is required in this population.

Crowdsourcing the Citation Screening Process for Systematic Reviews: Validation Study.

BACKGROUND: Systematic reviews (SRs) are often cited as the highest level of evidence available as they involve the identification and synthesis of published studies on a topic. Unfortunately, it is increasingly challenging for small teams to complete SR procedures in a reasonable time period, given the exponential rise in the volume of primary literature. Crowdsourcing has been postulated as a potential solution. OBJECTIVE: The feasibility objective of this study was to determine whether a crowd would be willing to perform and complete abstract and full text screening. The validation objective was to assess the quality of the crowd's work, including retention of eligible citations (sensitivity) and work performed for the investigative team, defined as the percentage of citations excluded by the crowd. METHODS: We performed a prospective study evaluating crowdsourcing essential components of an SR, including abstract screening, document retrieval, and full text assessment. Using CrowdScreenSR citation screening software, 2323 articles from 6 SRs were available to an online crowd. Citations excluded by less than or equal to 75% of the crowd were moved forward for full text assessment. For the validation component, performance of the crowd was compared with citation review through the accepted, gold standard, trained expert approach. RESULTS: Of 312 potential crowd members, 117 (37.5%) commenced abstract screening and 71 (22.8%) completed the minimum requirement of 50 citation assessments. The majority of participants were undergraduate or medical students (192/312, 61.5%). The crowd screened 16,988 abstracts (median: 8 per citation; interquartile range [IQR] 7-8), and all citations achieved the minimum of 4 assessments after a median of 42 days (IQR 26-67). Crowd members retrieved 83.5% (774/927) of the articles that progressed to the full text phase. A total of 7604 full text assessments were completed (median: 7 per citation; IQR 3-11). Citations from all but 1 review achieved the minimum of 4 assessments after a median of 36 days (IQR 24-70), with 1 review remaining incomplete after 3 months. When complete crowd member agreement at both levels was required for exclusion, sensitivity was 100% (95% CI 97.9-100) and work performed was calculated at 68.3% (95% CI 66.4-70.1). Using the predefined alternative 75% exclusion threshold, sensitivity remained 100% and work performed increased to 72.9% (95% CI 71.0-74.6; P<.001). Finally, when a simple majority threshold was considered, sensitivity decreased marginally to 98.9% (95% CI 96.0-99.7; P=.25) and work performed increased substantially to 80.4% (95% CI 78.7-82.0; P<.001). CONCLUSIONS: Crowdsourcing of citation screening for SRs is feasible and has reasonable sensitivity and specificity. By expediting the screening process, crowdsourcing could permit the investigative team to focus on more complex SR tasks. Future directions should focus on developing a user-friendly online platform that allows research teams to crowdsource their reviews.

Target oxygen saturation and development of pulmonary hypertension and increased pulmonary vascular resistance in preterm infants.

OBJECTIVE: Determine whether higher targeted oxygen levels are associated with reduced incidence of pulmonary hypertension (PH) and elevated pulmonary vascular resistance (PVR) in extremely premature infants. STUDY DESIGN: Retrospective chart review of 252 extremely preterm infants (<29 weeks), who underwent echocardiogram prior to discharge. PH rates were compared during periods (June 2012-May 2015 and June 2015-April 2016) when lower (88-92%) or higher (90-95%) oxygen saturation targets were used. PH was determined on echocardiography. The ratio of pulmonary artery acceleration time to right ventricular ejection time was computed, with values <0.31 indicative of elevated PVR. Survival analysis compared the effects of oxygen saturation group on development/resolution of PH and elevated PVR. RESULTS: The higher saturation group had significantly lower risk of developing PH (hazard ratio (HR) = 0.50, 95%CI 0.26-0.95; P = 0.03) or elevated PVR (HR = 0.55, 95%CI 0.38-0.81; P = 0.002), compared to the lower oxygen saturation group. Median time to PH development was significantly shorter in the lower saturation group than in the higher saturation group (5 days vs 12 days; P = 0.02), as was time to development of elevated PVR (4 days vs 6 days; P < 0.001). Duration of PH (P = 0.12) and elevated PVR (P = 0.86) did not differ significantly between groups. Cumulative incidence of PH (P = 0.04) and elevated PVR (P = 0.01) at 36 weeks post-menstrual age was significantly lower in the high saturation group compared to the lower saturation group. CONCLUSION: Higher targeted oxygen saturation was associated with reduced risk of PH or elevated PVR in extremely preterm infants compared to lower oxygen saturation target.

Efficacy of Malignant Hyperthermia Association of the United States-Recommended Methods of Preparation for Malignant Hyperthermia-Susceptible Patients Using Dräger Zeus Anesthesia Workstations and Associated Costs.

BACKGROUND: The objective of this study was to assess the efficacy and cost of Malignant Hyperthermia Association of the United States-recommended methods for preparing Dräger Zeus anesthesia workstations (AWSs) for the malignant hyperthermia-susceptible patient. METHODS: We studied washout profiles of sevoflurane, isoflurane, and desflurane in 3 Zeus AWS following 3 preparation methods. AWS was primed with 1.2 minimum alveolar concentration anesthetic for 2 hours using 2 L/min fresh gas flow, 500 mL tidal volume, and 12/min respiratory rate. Two phases of washout were performed: high flow (10 L/min) until anesthetic concentration was <5 parts per million (ppm) for 20 minutes and then low flow (3 L/min) for 20 minutes to identify the rebound effect. Preparation methods are as follows: method 1 (M1), changing disposables (breathing circuit, soda lime, CO2 line, and water traps); method 2 (M2), M1 plus replacing the breathing system with an autoclaved one; and method 3 (M3), M1 plus mounting 2 activated charcoal filters on respiratory limbs. Primary outcomes are as follows: time to obtain anesthetic concentration <5 ppm in the high-flow phase, peak anesthetic concentrations in the low-flow phase, and for M3 only, peak anesthetic concentration after 70 minutes of low-flow phase, when activated charcoal filters are removed. Secondary outcomes are as follows: cost analysis of time and resources to obtain anesthetic concentration <5 ppm in each method and a vapor-free Zeus AWS. Sensitivity analyses were performed using alternative assumptions regarding the costs and the malignant hyperthermia-susceptible caseload per year. RESULTS: Primary outcomes were as follows: M3 instantaneously decreased anesthetic concentration to <1 ppm with minimal impact of low-flow phase. M1 (median, 88 minutes; 95% confidence interval [CI], 69-112 minutes) was greater than M2 (median, 11 minutes; 95% CI, 9-15 minutes). Means of peak rebound anesthetic concentrations in M1, M2, and M3 were 15, 6, and 1 ppm, respectively (P < .001). Anesthetic concentration increased 33-fold (95% CI, 21-50) after removing charcoal filters (from 0.7 to 20 ppm). The choice of anesthetic agents did not impact the results. Secondary outcomes were as follows: M3 was the lowest cost when the cost of lost operating room (OR) time due to washout was included, and M1 was the lowest cost when it was not included. When the cost of lost OR time due to washout was considered the estimated cost/case of M3 was US $360 (M1, US $2670; M2, US $969; and a "vapor-free" Zeus AWS was US $930). The OR time and equipment costs represent the largest differentiators among the methods. CONCLUSIONS: Institutions in which demand for OR time has exceeded capacity should consider M3, and institutions with surplus OR capacity should consider M1.

Trainees success rates with intubation to suction meconium at birth.

OBJECTIVES: To assess the success rate and main reasons for failure of intubation performed by medical trainees to suction meconium below the vocal cords in non-vigorous infants delivered at ≥36 week gestation. DESIGN: We conducted a prospective cohort study involving 54 residents and nine neonatology fellows in a Canadian level 3 neonatal intensive care unit. Endotracheal intubation to suction meconium was performed using a videolaryngoscope, the video screen being covered during the procedure. All videos were reviewed by two experts blinded to the procedure and to the identity of the trainee. RESULTS: Sixteen videos were available to review between July 2014 and March 2016. Intubation success rate assessed by the reviewers was 6%, compared with 21% as assessed by the trainees. The most common reasons for intubation failure were an improper view of the glottis (87%) and meconium or secretions obscuring the view (67%). 36 % of the time, the trainees identified different reasons for intubation failure than the reviewers. CONCLUSION: Success rate of neonatal intubation to suction meconium was much lower than the success rate reported on infants without meconium. Teaching should be geared towards the most common reasons for intubation failure, possibly using video-based teaching.

Insulin Resistance and Hypertension in Obese Youth With Sleep-Disordered Breathing Treated With Positive Airway Pressure: A Prospective Multicenter Study.

STUDY OBJECTIVES: There is evidence that cardiometabolic disease associated with obesity and sleep-disordered breathing (SDB) in adults is present in youth. SDB is often treated with positive airway pressure (PAP) in youth with obesity. Our aims were to determine: (1) the prevalence of cardiometabolic disease and (2) whether PAP improves markers of cardiometabolic disease, in youth with obesity and newly diagnosed moderate-severe SDB. METHODS: A prospective multicenter cohort study was conducted in youth (8 to 16 years old) with obesity, prescribed PAP therapy for newly diagnosed moderate-severe SDB. Assessments occurred at baseline and at 6 and 12 months. Outcomes included markers of insulin resistance (change in homeostasis model assessment of insulin resistance (HOMA-IR) at 6 months = primary outcome), hypertension (24-hour ambulatory/blood pressure) and inflammation (high-sensitivity C-reactive protein: hs-CRP). RESULTS: Twenty-seven participants were enrolled. Of those with baseline testing available, 10/25 (40%) had HOMA-IR above the 97th percentile, 10/23 (44%) were hypertensive, 16/23 (70%) had loss of nocturnal blood pressure dip and hs-CRP was elevated in 16/27 (64%). There were no significant changes over time in markers of metabolic dysfunction or blood pressure, nor between PAP-adherent and non-adherent subgroups. CONCLUSIONS: In youth with obesity and SDB, metabolic dysfunction and hypertension were highly prevalent. There were no statistically significant improvements in cardiometabolic markers 1 year after the prescription of PAP therapy, although clinically relevant improvements were seen in insulin resistance and systolic blood pressure load, important predictors of future risk of cardiovascular disease. Larger, longer-term studies are needed to determine whether PAP improves cardiometabolic outcomes in obese youth. COMMENTARY: A commentary on this article appears in this issue on page 1025.

Poractant alfa versus bovine lipid extract surfactant for infants 24+0 to 31+6 weeks gestational age: A randomized controlled trial.

OBJECTIVES: To compare the efficacy and safety of poractant alfa and bovine lipid extract surfactant in preterm infants. STUDY DESIGN: Randomized, partially-blinded, multicenter trial. Infants <32 weeks needing surfactant before 48 hours were randomly assigned to receive poractant alfa or bovine lipid extract surfactant. The primary outcome was being alive and extubated at 48 hours post-randomization. Secondary outcomes included need for re-dosing, duration of respiratory support and oxygen, bronchopulmonary dysplasia, mortality and complications during administration. RESULTS: Three centers recruited 87 infants (mean 26.7 weeks and 906 grams) at a mean age of 5.9 hours, between March 2013 and December 2015. 21/42 (50%) were alive and extubated at 48 hours in the poractant alfa group vs 26/45 (57.8%) in the bovine lipid extract surfactant group; adjusted OR 0.76 (95% CI 0.30-1.93) (p = 0.56). No differences were observed in the need to re-dose. Duration of oxygen support (41.5 vs 62 days; adjusted OR 1.69 95% CI 1.02-2.80; p = 0.04) was reduced in infants who received poractant alfa. We observed a trend in bronchopulmonary dysplasia among survivors (51.5% vs 72.1%; adjusted OR 0.35 95%CI 0.12-1.04; p = 0.06) favoring poractant alfa. Twelve infants died before discharge, 9 in the poractant alfa group and 3 in the bovine lung extract group. Severe airway obstruction following administration was observed in 0 (poractant alfa) and 5 (bovine lipid extract surfactant) infants (adjusted OR 0.09 95%CI <0.01-1.27; p = 0.07). CONCLUSION: No statistically significant difference was observed in the proportion of infants alive and extubated within 48h between the two study groups. Poractant alfa may be more beneficial and associated with fewer complications than bovine lipid extract surfactant. However, we observed a trend towards higher mortality in the poractant alfa group. Larger studies are needed to determine whether observed possible benefits translate in shorter hospital admissions, or other long term benefits and determine whether there is a difference in mortality.

Diagnostic Accuracy of Neuromonitoring for Identification of New Neurologic Deficits in Pediatric Spinal Fusion Surgery.

BACKGROUND: Intraoperative neuromonitoring (IONM) modalities, transcranial motor-evoked potentials (TcMEPs), and somatosensory-evoked potentials (SSEPs) are accepted methods to identify impending spinal cord injury during spinal fusion surgery. Debate exists over sensitivity and specificity of these modalities. Our purpose was to measure the incidence of new neurologic deficits (NNDs) and estimate sensitivity and specificity of IONM modalities. METHODS: Institutional Ethics Board approval was obtained to review charts of patients younger than 22 years undergoing scoliosis surgery from 2007 to 2014 retrospectively. The definition of true-positive patients included two subgroups: (1) patients with an IONM alert, which did not resolve despite the interventions and had a NND postoperatively; or (2) patients with an IONM alert triggering interventions and the alert resolved with no NND postoperatively. Subgroup 2 of the definition is debatable; thus, we performed a multiple sensitivity analysis with three assumptions. Assumption 1: without interventions, all such patients would have experienced NNDs (assumption used in previous studies); Assumption 2: without intervention, half of these patients would have experienced NNDs; Assumption 3: without intervention, none of these of patients would have experienced NNDs. RESULTS: We included 296 patients. Patients with incomplete charts (n = 3), no IONM monitoring (n = 11), and inadequate baseline IONM (n = 7) were excluded. The incidence of NND was 3.7% (95% confidence interval, 2.1%-6.5%). Successful IONM in at least one modality was obtained in 275 patients (92.9%), of whom 268 (97.5%) and 259 (94.2%) had successful baseline TcMEP or SSEP signals, respectively. Fifty-one (17%) patients had IONM alerts, 41 were only TcMEP, 5 were only SSEP, and 5 were in both modalities. After interventions, 42 (82%) patients recovered, 41 had no NND (true-positive under Assumption (1), but one developed a NND (false-negative). Of the 9 patients with no alert recovery, 6 had a NND (true-positive) and 3 did not (false-positives). Of the remaining 224 patients with no alerts, 221 had no NND (true-negatives) and 3 did (false-negatives). Sensitivity was estimated to be 93.5%, 92.2%, and 46.7% for TcMEPs, combination (either TcMEPs or SSEPs), and SSEPs, respectively. Multiple sensitivity analysis demonstrated that sensitivity and specificity vary markedly with different assumptions. CONCLUSION: TcMEPs are more sensitive than SSEP at detecting an impending NND. IONM modalities are highly specific. Both sensitivity and specificity are impacted substantially by assumptions of the impact of interventions on alerts and NND. Properly designed, controlled, multicenter studies are required to establish diagnostic accuracy of IONM in scoliosis surgery.

Mobile Endoscopy vs Video Tower: A Prospective Comparison of Video Quality and Diagnostic Accuracy.

OBJECTIVE: To determine if any significant difference exists between endoscopic videos captured with a mobile adaptor and videos captured with a traditional tower. STUDY DESIGN: Prospective controlled blinded comparison of mobile endoscopic videos captured through 2 methods. METHODS: Thirty randomly selected patients underwent video endoscopy with both mobile and video tower recording methods. Sixty videos were edited into a series of 10-second clips. Thirteen otolaryngology staff and residents rated the video quality and provided a diagnosis for each video. RESULTS: We found no significant difference in the video quality ratings between mobile and tower videos (mean difference, -0.07; P < .37). Similarly, we found no significant difference in the observers' diagnostic accuracy (mean difference, 1.54%; P < .686). CONCLUSION: With adequate power, our study was unable to demonstrate a difference between mobile adapter videos and tower videos. Our findings suggest that mobile adapter videos may reasonably be used in lieu of tower videos in clinical practice.