Newborn self-inflating manual resuscitators: precision robotic testing of safety and reliability

AimA controlled bench test was undertaken to determine the performance variability among a range of neonatal self-inflating bags (SIB) compliant with current International Standards Organisation (ISO).IntroductionUse of SIB to provide positive pressure ventilation during newborn resuscitation is a common emergency procedure. The United Nations programmes advocate increasing availability of SIB in low-income and middle-income nations and recommend devices compliant with ISO. No systematic study has evaluated variance in different models of neonatal SIB.Methods20 models of SIB were incrementally compressed by an automated robotic device simulating the geometry and force of a human hand across a range of precise distances in a newborn lung model. Significance was calculated using analysis of variance repeated measures to determine the relationship between distance of SIB compression and delivered ventilation. A pass/fail was derived from a composite score comprising: minimum tidal volume; coefficient of variation (across all compression distances); peak pressures generated and functional compression distance.ResultsTen out of the 20 models of SIB failed our testing methodology. Two models could not provide safe minimum tidal volumes (2.5–5 mL); six models exceeded safety inflation pressure limit >45 cm H2O, representing 6% of their inflations; five models had excessive coefficient of variation (>30% averaged across compression distances) and three models did not deliver inflation volumes >2.5 mL until approximately 50% of maximum bag compression distance was reached. The study also found significant intrabatch variability and forward leakage.ConclusionCompliance of SIBs with ISO standards may not guarantee acceptable or safe performance to resuscitate newborn infants.

Download Full-text

Basic principles of neonatal bubble CPAP: effects on CPAP delivery and imposed work of breathing when altering the original design

Archives of Disease in Childhood - Fetal and Neonatal Edition ◽

10.1136/archdischild-2019-318073 ◽

2020 ◽

Vol 105 (5) ◽

pp. 550-554

Author(s):

Sonja Baldursdottir ◽

Markus Falk ◽

Snorri Donaldsson ◽

Baldvin Jonsson ◽

Thomas Drevhammar

Keyword(s):

High Resistance ◽

Low Income ◽

Dead Space ◽

Airway Pressure ◽

Work Of Breathing ◽

Lung Model ◽

Original Design ◽

Middle Income ◽

Low Resistance ◽

Mechanical Lung

BackgroundThe original bubble continuous positive airway pressure (bCPAP) design has wide-bore tubing and a low-resistance interface. This creates a stable airway pressure that is reflected by the submersion depth of the expiratory tubing. Several systems with alterations to the original bCPAP design are now available. Most of these are aimed for use in low-income and middle-income countries and have not been compared with the original design.ObjectiveWe identified three major alterations to the original bCPAP design: (1) resistance of nasal interface, (2) volume of dead space and (3) diameter of expiratory tubing. Our aim was to study the effect of these alterations on CPAP delivery and work of breathing in a mechanical lung model. Dead space should always be avoided and was not further tested.MethodsThe effect of nasal interface resistance and expiratory tubing diameter was evaluated with simulated breathing in a mechanical lung model without interface leakage. The main outcome was delivered CPAP and imposed work of breathing.ResultsHigh-resistance interfaces and narrow expiratory tubing increased the work of breathing. Additionally, narrow expiratory tubing resulted in higher CPAP levels than indicated by the submersion depth.ConclusionOur study shows the significant effect on CPAP delivery and imposed work of breathing when using high-resistance interfaces and narrow expiratory tubing in bCPAP systems. New systems should include low-resistance interfaces and wide-bore tubing and be compared with the original bCPAP. Referring to all systems that bubble as bCPAP is misleading and potentially hazardous.

Download Full-text

Norrie disease gene polymorphism in Indonesian infants with retinopathy of prematurity

BMJ Open Ophthalmology ◽

10.1136/bmjophth-2018-000211 ◽

2019 ◽

Vol 4 (1) ◽

pp. e000211

Author(s):

J Edy Siswanto ◽

Sudarto Ronoatmodjo ◽

Rita S Sitorus ◽

Ag Soemantri ◽

Iswari Setijaningsih ◽

...

Keyword(s):

Low Income ◽

Retinopathy Of Prematurity ◽

Genetic Factors ◽

Population Sample ◽

Newborn Infants ◽

Control Group ◽

Preterm Newborn ◽

Middle Income ◽

Norrie Disease ◽

Middle Income Countries

ObjectiveRetinopathy of prematurity (ROP) is a major cause of blindness in newborn infants, which also occurs in low-income and middle-income countries. Why ROP progresses in some infants while it regresses in others is still presently unknown. Studies suggest that genetic factors might be involved. Mutations in the Norrie disease (ND) gene are suspected to be related to advanced ROP development. Indonesia is a country with relatively high incidence of ROP, yet the role of these genetic factors in the pathogenesis of ROP cases is still unknown. The study aimed to investigate the presence of mutations in ND on the X chromosome in infants with both non-advanced and advanced ROP in Indonesia.Methods and AnalysisThis is a case–control study of polymorphisms in six variants within the ND gene in exon 3, C597A, L108P, R121W, A105T, V60E and C110G, in preterm newborn infants in four major hospitals in Greater Jakarta, Indonesia.ResultsWe included 162 preterm newborn infants. ROP was diagnosed in 83 infants, and 79 infants served as controls. Among those with ROP, 57 infants had type 2, while others had type 1. We did not find any gene polymorphisms in any of the infants with ROP nor in the control group.ConclusionWe conclude that it is very unlikely that the six polymorphisms in exon 3 of the ND gene studied in this paper are involved in the development or progression of ROP in preterm infants in our population sample in Indonesia.

Download Full-text

Challenges of clinical trials in low- and middle-income countries

International Psychiatry ◽

10.1192/s1749367600003039 ◽

2012 ◽

Vol 9 (2) ◽

pp. 30-31

Author(s):

Akwasi Osei

Keyword(s):

Clinical Trials ◽

Low Income ◽

High Income ◽

International Standards ◽

Low Income Countries ◽

Profit Motive ◽

High Quality ◽

Middle Income ◽

Middle Income Countries ◽

Low And Middle Income

Clinical trials have been conducted almost wholly in high-income countries until recently, yet their results may not always be valid or applicable in middle- and low-income countries. Clinical trials are now, though, increasingly being done in less wealthy countries. While this is welcome, there is a need to ensure the profit motive does not override the benefits. Partnership with local counterparts while adhering to international standards should help to maintain high-quality output from clinical trials.

Download Full-text

T-piece resuscitators: can they provide safe ventilation in a low compliant newborn lung?

Archives of Disease in Childhood - Fetal and Neonatal Edition ◽

10.1136/archdischild-2019-318673 ◽

2020 ◽

Vol 106 (1) ◽

pp. 25-30 ◽

Cited By ~ 2

Author(s):

Murray Kenneth Hinder ◽

Thomas Drevhammar ◽

Snorri Donaldsson ◽

Matthew Boustred ◽

Matthew Crott ◽

...

Keyword(s):

Gas Flow ◽

Lung Compliance ◽

Lung Model ◽

Bench Test ◽

Positive Pressure ◽

Test Model ◽

Inflation Pressure ◽

Emergency Rooms ◽

Test Lung ◽

Single Operator

BackgroundT-piece resuscitators (TPRs) are used for primary newborn resuscitation in birthing and emergency rooms worldwide. A recent study has shown spikes in peak inflation pressure (PIP) over set values with two brands of TPRs inbuilt into infant warmer/resuscitation platforms. We aimed to compare delivered ventilation between two TPR drivers with inflation pressure spikes to a standard handheld TPR in a low test lung compliance (Crs), leak-free bench test model.MethodsA single operator provided positive pressure ventilation to a low compliance test lung model (Crs 0.2–1 mL/cmH2O) at set PIP of 15, 25, 35 and 40 cmH2O. Two TPR devices with known spikes (Draeger Resuscitaire, GE Panda) were compared with handheld Neopuff (NP). Recommended settings for positive end-expiratory pressure (5 cmH2O), inflation rate of 60/min and gas flow rate 10 L/min were used.Results2293 inflations were analysed. Draeger and GE TPR drivers delivered higher mean PIP (Panda 18.9–49.5 cmH2O; Draeger 21.2–49.2 cmH2O and NP 14.8–39.9 cmH2O) compared with set PIP and tidal volumes (TVs) compared with the NP (Panda 2.9–7.8 mL; Draeger 3.8–8.1 mL; compared with NP 2.2–6.0 mL), outside the prespecified acceptable range (±10% of set PIP and ±10% TV compared with NP).ConclusionThe observed spike in PIP over set values with Draeger and GE Panda systems resulted in significantly higher delivered volumes compared with the NP with identical settings. Manufacturers need to address these differences. The effect on patient outcomes is unknown.

Download Full-text

Conducting clinical research in a resource-constrained setting: lessons from a longitudinal cohort study in The Gambia

BMJ Global Health ◽

10.1136/bmjgh-2021-006419 ◽

2021 ◽

Vol 6 (8) ◽

pp. e006419

Author(s):

Abdulazeez Imam ◽

Oghenebrume Wariri ◽

Tida Dibbasey ◽

Abdoulie Camara ◽

Anthony Mendy ◽

...

Keyword(s):

Clinical Research ◽

Low Income ◽

Newborn Infants ◽

Good Clinical Practice ◽

The Gambia ◽

London School ◽

Resource Constrained ◽

Middle Income ◽

The Usa ◽

Expanded Program On Immunization

Clinical research conducted to Good Clinical Practice (GCP) standards is increasingly being undertaken in resource-constrained low-income and middle-income countries (LMICs) settings. This presents unique challenges that differ from those faced in high-income country (HIC) contexts, due to a dearth of infrastructure and unique socio-cultural contexts. Field experiences by research teams working in these LMIC contexts are thus critical to advancing knowledge on successful research conduct in these settings. The Medical Research Council Unit The Gambia at London School of Hygiene and Tropical Medicine has operated in The Gambia, a resource-constrained LMIC for over 70 years and has developed numerous research support platforms and systems. The unit was the lead clinical collaborator in a recently completed Expanded Program on Immunization Consortium (EPIC) study, involving a multicountry collaboration across five countries including the USA, Canada, Belgium, Papua New Guinea and The Gambia. The EPIC study recruited and completed follow-up of 720 newborn infants over 2 years. In this paper, we provide in-depth field experience covering challenges faced by the Gambian EPIC team in the conduct of this study. We also detail some reflections on these challenges. Our findings are relevant to the international research community as they highlight practical day-to-day challenges in conducting GCP standard clinical research in resource-constrained LMIC contexts. They also provide insights on how study processes can be adapted early during research planning to mitigate challenges.

Download Full-text