Amit Mukerji

Nasal High-Frequency Oscillation for Lung Carbon Dioxide Clearance in the Newborn

Background: Noninvasive ventilation has been used increasingly in recent years to minimize the duration of endotracheal mechanical ventilation in neonates due to its association with lung injury. Nasal high-frequency oscillation (nHFO) is a relatively new noninvasive modality but evidence for its use is limited. Objective: The goal of this study was to compare the CO2 clearance efficacy of nHFO and noninvasive positive pressure ventilation (NIPPV) in a neonatal lung model. Design/Methods: A newborn mannequin with dimensions and anatomy similar to a term infant was utilized. It was connected to a commercially available neonatal mechanical ventilator using a manufacturer-provided nasal adaptor. Various modes of noninvasive ventilation were compared as CO2 clearance was measured at the oropharynx by an end-tidal CO2 analyzer following the addition of a known amount of CO2 into the lung. Measurements were obtained at two different lung compliances using nHFO and compared with nCMV and nasal continuous positive airway pressure (nCPAP) as a control. Pressures near the nasal adaptor and the larynx were simultaneously measured with in-line pressure transducers. Results: Whereas no CO2 elimination was observed under nCPAP, its clearance with nHFO was 3-fold greater as compared to NIPPV. On nHFO, CO2 clearance was inversely proportional to frequency and maximal at 6 and 8 Hz. At a lower lung compliance, CO2 clearance was significantly higher at 6 Hz as compared to 10 Hz. During nHFO set to deliver a MAP of 10.0, we documented pressures of 7.2 ± 0.3 at the nasal adaptor and only 2.3 ± 0.3 cm H2O at the larynx. Conclusions: Nasal HFO is effective and superior to NIPPV at lung CO2 elimination in a newborn mannequin model. The use of nHFO as the preferred mode of noninvasive ventilation warrants further clinical studies.

Use of Noninvasive High-Frequency Ventilation in the Neonatal Intensive Care Unit: A Retrospective Review

OBJECTIVE The aim of the article is to review the effectiveness of neonatal noninvasive high-frequency ventilation (NIHFV) in preventing endotracheal mechanical ventilation. STUDY DESIGN Retrospective case series including all 79 instances of NIHFV use at four participating centers between July 2010 and September 2012. RESULTS In 73% of cases, NIHFV was used as rescue after another noninvasive mode, and prophylactically (postextubation) in the remainder. In 58% of cases, infants transitioned to another noninvasive mode, without requiring intubation. There were significant reductions in the mean (SD) number of apneas, bradycardias, or desaturations (over 6 hours) (3.2 [0.4] vs. 1.2 [0.3]; p < 0.001), FiO2 (48 [3] vs. 40 [2]%; p < 0.001) and CO2 levels (74 [6] vs. 62 [4] mm Hg; p = 0.025] with NIHFV. No NIHFV-related complications were noted. CONCLUSIONS NIHFV is a promising NIV mode that may help prevent or delay intubation and deserves further clinical research.

Survey of noninvasive respiratory support practices in Canadian neonatal intensive care units

To evaluate practice variation with respect to noninvasive respiratory support (NRS) use across Canadian neonatal intensive care units (NICUs).

Head Growth Trajectory and Neurodevelopmental Outcomes in Preterm Neonates.

A retrospective analysis revealed that poor HG during the neonatal and postdischarge periods was associated with motor and cognitive delays at 16 to 36 months. OBJECTIVES: To evaluate the association between head growth (HG) during neonatal and postdischarge periods and neurodevelopmental outcomes of preterm neonates of <29 weeks gestational age. METHODS: We conducted a retrospective cohort study of infants <29 weeks gestational
age admitted between 2009 and 2011 to participating Canadian Neonatal Network
units and followed by Canadian Neonatal Follow-Up Network clinics. Differences in head circumference (ΔHC) z score were calculated for 3 time periods, which include admission to discharge, discharge to follow-up at 16-36 months, and admission to follow-up. These were categorized in 1 reference group (ΔHC z score between −1 and +1) and 4 study groups (ΔHC z score of <−2, between −2 to −1, +1 to +2, and >+2). Neurodevelopmental outcomes were compared with the reference group. RESULTS: 1973 infants met the inclusion criteria. Poor HG occurred frequently during the NICU admission (ΔHC z score <−2 in 24% infants versus 2% infants post-discharge) with a period of “catch-up” growth postdischarge. Significant neurodevelopmental impairment was higher in infants with the poorest HG from admission to follow-up (adjusted odds ratio 2.18, 95% confidence interval 1.50–3.15), specifically cognitive and motor delays. Infants with poor initial HG and catch-up postdischarge have a lower adjusted odds ratio of significant neurodevelopmental impairment (0.35, 95% CI 0.16–0.74). Infants with poor HG received a longer duration of parenteral nutrition and mechanical ventilation and had poor weight gain. CONCLUSIONS: Poor HG during the neonatal and postdischarge periods was associated with motor and cognitive delays at 16 to 36 months.

Pregnancy-induced hypertension and neonatal outcomes: a systematic review and meta-analysis

Objective:Pregnancy-induced hypertension (PIH) is associated with preterm delivery but its independent impact on neonatal outcomes remains unclear. We sought to systematically review and meta-analyze clinical outcomes of preterm infants <37 weeks’ gestation born to mothers with and without PIH.Study Design:Medline, Embase, PsychINFO and CINAHL were searched from January 2000 to October 2016. Studies with low-moderate risk of bias reporting neonatal outcomes based on PIH as primary exposure variable were included. Data were extracted independently by two co-authors.Results:PIH was associated with lower mortality (3 studies; adjusted odds ratio (aOR) 0.65; 95% confidence interval (CI) 0.54 to 0.79), lower severe retinopathy of prematurity (ROP) (2 studies; aOR 0.83; 0.72 to 0.96) and lower severe brain injury (2 studies; unadjusted OR (uOR) 0.57; 0.49 to 0.66). No association between PIH and short-term respiratory outcomes, bronchopulmonary dysplasia (BPD) or necrotizing enterocolitis (NEC) was identified. In subgroup analysis among infants <29 weeks’ gestation, BPD odds were higher (3 studies; aOR 1.15; 1.06 to 1.26), whereas mortality lower (2 studies; aOR 0.73; 0.69 to 0.77). In subgroup analysis limited to severe PIH, odds of mortality (3 studies; uOR 2.36; 1.07 to 5.22) and invasive ventilation (3 studies; uOR 3.26; 1.11 to 9.61) were higher. In subgroup analysis limited to preeclampsia, odds of BPD (3 studies; uOR 1.21; 95% CI:1.03 to 1.43) and NEC were higher (3 studies; uOR 2.79; 95% CI:1.57 to 4.96).Conclusion:PIH was associated with reduced odds of mortality and ROP (all infants), but higher odds for BPD (<29 weeks’ gestation). The paradoxical reduction in mortality may be due to survival bias and deserves further exploration in future studies.

Introduction of microsystems in a level 3 neonatal intensive care unit—an interprofessional approach

BackgroundGrowth of neonatal intensive care units in number and size has raised questions towards ability to maintain continuity and quality of care. Structural organization of intensive care units is known as a key element for maintaining the quality of care of these fragile patients. The reconstruction of megaunits of intensive care to smaller care units within a single operational service might help with provision of safe and effective care.Methods/DesignThe clinical team and patient distribution lay out, admission and discharge criteria and interdisciplinary round model was reorganized to follow the microstructure philosophy. A working group met weekly to formulate the implementation planning, to review the adaptation and adjustment process and to ascertain the quality of implementation following the initiation of the microsystem model.DiscussionIn depth examination of microsystem model of care in this study, provides systematic evaluation of this model on variable aspects of health care. The individual projects of this trial can be source of solid evidence for guidance of future decisions on optimized model of care for the critically ill newborns.Trial registrationClinicalTrial.gov, NCT02912780. Retrospectively registered on 22 September 2016.

Neonatal respiratory outcomes in pregnancy induced hypertension: introducing a novel index

Abstract Objective: To evaluate short-term respiratory outcomes, mortality and bronchopulmonary dysplasia (BPD) in preterm infants born to mothers with and without pregnancy induced hypertension (PIH). Methods: Exposed infants <33 weeks’ gestation were matched to controls in a 1:2 ratio, based on gestation, sex and antenatal steroid exposure in this retrospective cohort study. Primary outcomes were a novel cumulative respiratory index (cRI) (product of mean airway pressure-hours and FiO2-hours while on invasive ventilation during first 72 hours), mortality and BPD. Results: Seventy-nine exposed infants were matched with 158 controls. cRI was higher in exposed infants (median 1854; IQR 186–13,901) versus controls (median 1359; IQR 210–11,302) but not statistically significant (p = .63). On conditional regression analysis, PIH did not predict cRI (adjusted β = 0.96; 95% CI = 0.79–1.17; p = .712). No association between PIH and mortality (unadjusted odds ratio [OR] = 3.14; 95% CI = 0.76–13.0; p=.11) was identified. PIH was significantly associated with BPD on univariate analysis (OR = 2.29; 95% CI = 1.02–5.17; p=.046), but not after adjustment (aOR = 1.26; 95% CI = 0.38–4.19; p=.7). Conclusions: PIH was not associated with cRI, mortality or BPD in this study. Further validation of cRI and exploration of its relationship with PIH as well as neonatal outcomes is warranted.

Sustained Quality Improvement in Outcomes of Preterm Neonates of <29 Weeks’ Gestational Age: Results from the Evidence-based Practice for Improving Quality Phase 3 (EPIQ-3)

Quality improvement initiatives in neonatology have yielded positive results; however, few programs have demonstrated sustainability. We evaluated an ongoing, national quality improvement initiative (Evidence-based Practice for Improving Quality Phase 3 (EPIQ-3)) on outcomes of preterm neonates with a gestational age (GA) of 220-286 weeks (i.e., from 22 weeks and 0 days of gestation to 28 weeks and 6 days of gestation). Data from 7459 neonates admitted to 25 Canadian centers between 2013 and 2017 were studied. Trends in mortality and major morbidities were evaluated. The number of neonates with a GA of 220-236 weeks increased from 90 in 2013 to 139 in 2017 without a significant change in any other GA categories. In the entire cohort, the odds of composite outcome of mortality or any major morbidity (adjusted odds ratio (AOR) 0.72, 95% confidence interval (CI) 0.61-0.84) and of necrotizing enterocolitis (AOR 0.66, 95% CI 0.49-0.89) were lower in 2017 than in 2013. When calculated per year, the odds of composite outcome (AOR 0.93, 95% CI 0.89-0.97) and odds of necrotizing enterocolitis (AOR 0.89, 95% CI 0.82-0.96) decreased significantly. Among the subgroup of neonates with a GA of 260-286 weeks, the odds of composite outcome (AOR 0.63, 95% CI 0.51-0.79), necrotizing enterocolitis (AOR 0.44, 95% CI 0.26-0.73), and nosocomial infection (AOR 0.64, 95% CI 0.49-0.84) were reduced. The collaborative, multidisciplinary, nationwide EPIQ-3 program improved outcomes of preterm neonates, and the improvement was sustainable over 5 years.