Continuous Positive Airway Pressure Strategies with Bubble Nasal Continuous Positive Airway Pressure: Not All Bubbling Is the Same: The Seattle Positive Airway Pressure System

Bubble devices versus other pressure sources for nasal continuous positive airway pressure in preterm infants

BACKGROUND

Several types of pressure sources, including underwater bubble devices, mechanical ventilators, and the Infant Flow Driver, are used for providing continuous positive airway pressure (CPAP) to preterm infants with respiratory distress. It is unclear whether the use of bubble CPAP versus other pressure sources is associated with lower rates of CPAP treatment failure, or mortality and other morbidity.  OBJECTIVES: To assess the benefits and harms of bubble CPAP versus other pressure sources (mechanical ventilators or Infant Flow Driver) for reducing treatment failure and associated morbidity and mortality in newborn preterm infants with or at risk of respiratory distress.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2023, Issue 1); MEDLINE (1946 to 6 January 2023), Embase (1974 to 6 January 2023), Maternity & Infant Care Database (1971 to 6 January 2023), and the Cumulative Index to Nursing and Allied Health Literature (1982 to 6 January 2023). We searched clinical trials databases and the reference lists of retrieved articles.

SELECTION CRITERIA

We included randomised controlled trials comparing bubble CPAP with other pressure sources (mechanical ventilators or Infant Flow Driver) for the delivery of nasal CPAP to preterm infants.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Two review authors separately evaluated trial quality, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference. We used the GRADE approach to assess the certainty of the evidence for effects on treatment failure, all-cause mortality, neurodevelopmental impairment, pneumothorax, moderate-severe nasal trauma, and bronchopulmonary dysplasia.

MAIN RESULTS

We included 15 trials involving a total of 1437 infants. All trials were small (median number of participants 88). The methods used to generate the randomisation sequence and ensure allocation concealment were unclear in about half of the trial reports. Lack of measures to blind caregivers or investigators was a potential source of bias in all of the included trials. The trials took place during the past 25 years in care facilities internationally, predominantly in India (five trials) and Iran (four trials). The studied pressure sources were commercially available bubble CPAP devices versus a variety of mechanical ventilator (11 trials) or Infant Flow Driver (4 trials) devices.  Meta-analyses suggest that the use of bubble CPAP compared with mechanical ventilator or Infant Flow Driver CPAP may reduce the rate of treatment failure (RR 0.76, 95% confidence interval (CI) 0.60 to 0.95; (I² = 31%); RD -0.05, 95% CI -0.10 to -0.01; number needed to treat for an additional beneficial outcome 20, 95% CI 10 to 100; 13 trials, 1230 infants; low certainty evidence). The type of pressure source may not affect mortality prior to hospital discharge (RR 0.93, 95% CI 0.64 to 1.36 (I² = 0%); RD -0.01, 95% CI -0.04 to 0.02; 10 trials, 1189 infants; low certainty evidence). No data were available on neurodevelopmental impairment. Meta-analysis suggests that the pressure source may not affect the risk of pneumothorax (RR 0.73, 95% CI 0.40 to 1.34 (I² = 0%); RD -0.01, 95% CI -0.03 to 0.01; 14 trials, 1340 infants; low certainty evidence). Bubble CPAP likely increases the risk of moderate-severe nasal injury (RR 2.29, 95% CI 1.37 to 3.82 (I² = 17%); RD 0.07, 95% CI 0.03 to 0.11; number needed to treat for an additional harmful outcome 14, 95% CI 9 to 33; 8 trials, 753 infants; moderate certainty evidence). The pressure source may not affect the risk of bronchopulmonary dysplasia (RR 0.76, 95% CI 0.53 to 1.10 (I² = 0%); RD -0.04, 95% CI -0.09 to 0.01; 7 trials, 603 infants; low certainty evidence).  AUTHORS' CONCLUSIONS: Given the low level of certainty about the effects of bubble CPAP versus other pressure sources on the risk of treatment failure and most associated morbidity and mortality for preterm infants, further large, high-quality trials are needed to provide evidence of sufficient validity and applicability to inform context- and setting-relevant policy and practice.

Adjusting ventilator settings to avoid air trapping in extremely premature infants reduces the need for tracheostomy and length of stay

Despite the improving understanding of how lung mechanics and tidal volume requirements evolve during the evolution of bronchopulmonary dysplasia (BPD), clinical management continues to be heterogeneous and inconsistent at many institutions. Recent reports have examined the use of high tidal-volume low respiratory rate strategies in these patients once disease has been well established to help facilitate their eventual extubation and improve their long-term neurodevelopmental outcomes. In this retrospective observational research study, we describe how intentional adjustment of ventilator settings based on patient lung mechanics by an interdisciplinary BPD team improved the care of the at-risk population of infants, reduced the need for tracheostomies, as well as length of stay over a period of over 3 years. The team aimed to establish consistency in the management of these children using a high tidal volume, low-rate approach, and titrating PEEP to address the autoPEEP and bronchomalacia that is frequently observed in this patient population.

Preserved pressure delivery during high-frequency oscillation of bubble CPAP in a premature infant lung model with both normal and abnormal lung mechanics

BACKGROUND

Bubble continuous positive airway pressure (BCPAP) generates pressure oscillations which are suggested to improve gas exchange through mechanisms similar to high frequency (HF) ventilation. In a previous in-vitro lung model with normal lung mechanics, significantly improved CO₂ washout was demonstrated using an HF interrupter in the supply flow of a BCPAP system. The effect of HF with BCPAP on delivered airway pressure (Paw) has not been fully investigated in a lung model having abnormal pulmonary mechanics.

OBJECTIVE

To measure Paw in an infant lung model simulating normal and abnormal pulmonary compliance and resistance while connected to a BCPAP system with superimposed HF oscillations created using an in-line flow interrupter.

DESIGN/METHODS

A premature infant lung model with either: normal lung mechanics, compliance 1.0 ml/cm H₂ O, airway resistance 56 cm H₂ O/(L/s); or abnormal mechanics, compliance 0.5 ml/cm H₂ O, airway resistance 136 cm H₂ O/(L/s), was connected to BCPAP with HF at either 4, 6, 8, 10, or 12 Hz. Paw was measured at BCPAPs of 4, 6, and 8 cm H₂ O and respiratory rates (RR) of 40, 60, and 80 breaths/min and 6.0 ml tidal volume.

RESULTS

Mean Paw averaged over all five frequencies showed no significant change from non-oscillated levels at all BCPAPs and RRs for both lung models. Paw amplitudes (peak-to-trough) during oscillation were significantly greater than the non-oscillated levels by an average of 1.7 ± 0.5 SD and 2.6 ± 0.5 SD cm H₂ O (p < .001) for the normal and abnormal models, respectively.

CONCLUSIONS

HF oscillation of BCPAP using a flow interrupter did not alter mean delivered Paw compared to non-oscillated BCPAP for both normal and abnormal lung mechanics models. This simple modification to BCPAP may be a useful enhancement to this mode of non-invasive respiratory support.

The safety and effectiveness of heated humidified high-flow nasal cannula as an initial ventilation method in the treatment of neonatal respiratory distress syndrome: A protocol for systematic review and meta-analysis

BACKGROUND

This study uses a method of systematic evaluation to evaluate the safety and effectiveness of heated humidified high-flow nasal cannula (HHHFNC) as an initial ventilation method in the treatment of neonatal respiratory distress syndrome (NRDS) scientifically. In the field of evidence-based medicine, this study provides a theoretical reference and basis for choosing appropriate initial non-invasive ventilation methods in the treatment of NRDS, thereby providing assistance for clinical treatment.

METHODS

The main electronic network databases were searched by computer, including 4 Chinese databases: CNKI, WangFang Data, CQVIP, SinoMed and 3 English databases: PubMed, The Cochrane Library and EMBASE, the time range of retrieval from the beginning of each database to September 1, 2020. The content involves all the published randomized controlled trials on the effectiveness of HHHFNC compared with NCPAP as an initial ventilation method in the treatment of NRDS. Using a search method that combines medical subject words and free words. Based on the Cochrane risk bias assessment tool, 2 researchers independently screen the literature, and then extract the data we needed in the literature, and cross-check. If it is difficult to decide whether to include literature, then turning to a third researcher for help and making a final decision after discussion, and using RevMan 5.3 and STATA 13.0 to analyze the relative data.

RESULTS

Based on the method of meta-analysis, this study analyzes the pre-determined outcome indicators through scientific statistical analysis, and compares the effectiveness and safety of HHHFNC compared with NCPAP as an initial ventilation method in the treatment of NRDS. All results will be published in peer-reviewed high-quality professional academic journals.

CONCLUSION

Based on evidence-based medicine, this study will obtain the establishing evidence of comparison that the clinical effectiveness and safety of HHHFNC compared with NCPAP as an initial ventilation method in the treatment of NRDS through the existing data and data, which provides the evidence support of evidence-based medicine in the treatment of NRDS.

OSF REGISTRATION NUMBER

September 17, 2020. osf.io/f6at4 (https://osf.io/f6at4).

Decreasing Chronic Lung Disease Associated with Bubble CPAP Technology: Experience at Five Years

Introduction:

Bubble continuous positive airway pressure (bCPAP) is associated with a decreased risk for chronic lung disease (CLD) in preterm neonates. This report examined the effectiveness of adopting bCPAP to reduce respiratory complications and medication usage in a community hospital NICU.

Methods:

The efficacy of bCPAP was assessed by retrospective examination and comparison of 45 neonates who received bCPAP and 87 neonates who received conventional ventilation only. Data on medication usage were also collected and analyzed.

Results:

After introduction of the bCPAP protocol, the median number of days on oxygen decreased in the bCPAP group compared with the conventional ventilation only group (median = 33 days, IQR = 7.5–66 vs median = 0, IQR = 0–0; P < 0.001). The exposure to conventional ventilation decreased in the bCPAP group compared with the conventional ventilation only group (median = 18 days, IQR = 5–42.5 vs median = 0, IQR = 0–7; P < 0.001). Postimplementation of bCPAP revealed decreases in CLD from 26 (30%) in the conventional ventilation only group to 2 (4%) in the bCPAP group (P = 0.002); there was also a significant decrease in the use of sedative medications in the bCPAP group compared with the conventional ventilation only group (mean = 5.20 doses, SD = 31.97 vs mean = 1.43, SD = 9.98; P < 0.001).

Conclusion:

The use of bCPAP results in significant decreases in the use of conventional ventilation, the risk for CLD, and the need for sedative medication.

Action research on neonatal nursing staff: Experiences caring for bubble continuous positive airway pressure patients

The objective of this study was to understand the experiences of special care nursery (SCN) nurses tending patients on bubble continuous positive airway pressure (bCPAP). The action research (AR) method with focus group interview was used, and five focus-group interviews were conducted between November 2015 and January 2016. Twenty SCN nurses who had cared neonates on bCPAP for at least one shift were recruited and interviewed. Six themes were revealed in two stages. The first stage was "experience of change," three themes evolved: "resistance to change," "lack of confidence on new care model," and "request administrative supports and resources from the hospital level." The second stage was "willing to take challenge," three themes evolved: "pursuit of proficiency in bCPAP care," "mastering bPCAP: acquiring self-efficacy, becoming competent, and collaborating as a team," and "the development of creative care methods." In the future when confronted with nurses resisting to new policies or changes, administrators should embrace their emotions, address their insecurity and fear, and provide adequate training to improve confidence through familiarity. Application of this model can help with policy implementation, thereby improving the overall caring quality.

A trial comparing continuous positive airway pressure (CPAP) devices in preterm infants

OBJECTIVE

To test the hypothesis that infants born <30 weeks' gestation supported by Seattle-PAP will have lower rates of continuous positive airway pressure (CPAP) failure than infants supported with conventional, Fisher&Paykel-CPAP (FP-CPAP).

STUDY DESIGN

Randomized trial (3/2017-01/2019) at 5 NICUs. The primary outcome was CPAP failure; subgroup analyses (gestational age, receipt antenatal corticosteroids) were performed.

RESULTS

A total of 232 infants were randomized. Infants in the Seattle-PAP and FP-CPAP groups had mean gestational ages of 27.0 and 27.2 weeks, respectively. We observed no differences in rates of treatment failure between Seattle-PAP (40/112, 35.7%) and FP-CPAP (38/120, 31.7%; risk difference, 4.1%; 95% CI, -8.1-16.2; P = 0.51). Subgroup analysis indicated no differences in rates of CPAP failure. We observed no differences between the two groups in frequencies of adverse events or duration of respiratory support.

CONCLUSIONS

Among infants born <30 weeks' gestation, rates of CPAP failure did not differ between Seattle-PAP and FP-CPAP.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome - 2019 Update

As management of respiratory distress syndrome (RDS) advances, clinicians must continually revise their current practice. We report the fourth update of "European Guidelines for the Management of RDS" by a European panel of experienced neonatologists and an expert perinatal obstetrician based on available literature up to the end of 2018. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, need for appropriate maternal transfer to a perinatal centre and timely use of antenatal steroids. Delivery room management has become more evidence-based, and protocols for lung protection including initiation of CPAP and titration of oxygen should be implemented immediately after birth. Surfactant replacement therapy is a crucial part of management of RDS, and newer protocols for its use recommend early administration and avoidance of mechanical ventilation. Methods of maintaining babies on non-invasive respiratory support have been further developed and may cause less distress and reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation using caffeine and, if necessary, postnatal steroids are also important considerations. Protocols for optimising general care of infants with RDS are also essential with good temperature control, careful fluid and nutritional management, maintenance of perfusion and judicious use of antibiotics all being important determinants of best outcome.

Evaluating the efficacy of Seattle-PAP for the respiratory support of premature neonates: study protocol for a randomized controlled trial

BACKGROUND

At birth, the majority of neonates born at <30 weeks of gestation require respiratory support to facilitate transition and ensure adequate gas exchange. Although the optimal approach to the initial respiratory management is uncertain, the American Academy of Pediatrics endorses noninvasive respiratory support with nasal continuous positive airway pressure (nCPAP) for premature neonates with respiratory insufficiency. Despite evidence for its use, nCPAP failure, requiring intubation and mechanical ventilation, is common. Recently, investigators have described a novel method to deliver bubble nCPAP, termed Seattle-PAP. While preclinical and pilot studies are encouraging regarding the potential value of Seattle-PAP, a large trial is needed to compare Seattle-PAP directly with the current standard of care for bubble nCPAP (Fisher & Paykel CPAP or FP-CPAP).

METHODS/DESIGN

We designed a multicenter, non-blinded, randomized controlled trial that will enroll 230 premature infants (22^0/7 to 29^6/7 weeks of gestation). Infants will be randomized to receive Seattle-PAP or FP-CPAP. The primary outcome is respiratory failure requiring intubation and mechanical ventilation. Secondary outcomes include measures of short- and long-term respiratory morbidity and cost-effectiveness.

DISCUSSION

This trial will assess whether Seattle-PAP is more efficacious and cost-effective than FP-CPAP in real-world practice among premature neonates.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03085329 . Registered on 21 March 2017.

Short term evaluation of respiratory effort by premature infants supported with bubble nasal continuous airway pressure using Seattle-PAP and a standard bubble device

Background

Almost one million prematurely born infants die annually from respiratory insufficiency, predominantly in countries with limited access to respiratory support for neonates. The primary hypothesis tested in the present study was that a modified device for bubble nasal continuous positive airway pressure (Bn-CPAP) would provide lower work of spontaneous breathing, estimated by esophageal pressure-rate products.

Methods

Infants born <32 weeks gestation and stable on Bn-CPAP with FiO₂ <0.30 were studied within 72 h following delivery. Esophageal pressures during spontaneous breathing were measured during 2 h on standard Bn-CPAP, then 2 h with Bn-CPAP using a modified bubble device presently termed Seattle-PAP, which produces a different pattern of pressure fluctuations and which provided greater respiratory support in preclinical studies, then 2 h on standard Bn-CPAP.

Results

All 40 infants enrolled completed the study and follow-up through 36 wks post menstrual age or hospital discharge, whichever came first. No infants were on supplemental oxygen at completion of follow-up. No infants developed pneumothoraces or nasal trauma, and no adverse events attributed to the study were observed. Pressure-rate products on the two devices were not different, but effort of breathing, assessed by areas under esophageal pressure-time curves, was lower with Seattle-PAP than with standard Bn-CPAP.

Conclusion

Use of Seattle-PAP to implement Bn-CPAP lowers the effort of breathing exerted even by relatively healthy spontaneously breathing premature neonates. Whether the lower effort of breathing observed with Seattle-PAP translates to improvements in neonatal mortality or morbidity will need to be determined by studies in appropriate patient populations.