A feasibility study evaluating a reservoir storage system for continuous oxygen delivery for children with hypoxemia in Kenya.

BACKGROUND: Supplemental oxygen is an essential treatment for childhood pneumonia but is often unavailable in low-resource settings or unreliable due to frequent and long-lasting power outages. We present a novel medium pressure reservoir (MPR) which delivers continuous oxygen to pediatric patients through power outages. METHODS: An observational case series pilot study assessing the capacity, efficacy and user appraisal of a novel MPR device for use in low-resource pediatric wards. We designed and tested a MPR in a controlled preclinical setting, established feasibility of the device in two rural Kenyan hospitals, and sought user feedback and satisfaction using a standardized questionnaire. RESULTS: Preclinical data showed that the MPR was capable of bridging power outages and delivering a continuous flow of oxygen to a simulated patient. The MPR was then deployed for clinical testing in nine pediatric patients at Ahero and Suba Hospitals. Power was unavailable for 2% of the total time observed due to 11 power outages (median 4.6 min, IQR 3.6-13.0 min) that occurred during treatment with the MPR. Oxygen flowrates remained constant across all 11 power outages. Feedback on the MPR was uniformly positive; all respondents indicated that the MPR was easy to use and provided clinically significant help to their patients. CONCLUSION: We present a MPR oxygen delivery device that has the potential to mitigate power insecurity and improve the standard of care for hypoxemic pediatric patients in resource-limited settings.

Efficacy and safety of oxygen-sparing nasal reservoir cannula for treatment of pediatric hypoxemic pneumonia in Uganda: a pilot randomized clinical trial.

BACKGROUND: Oxygen is an essential therapy for hypoxemia but is scarce in low-income settings. Oxygen conserving devices optimize delivery, but to date have been designed for adults in high-income settings. Here we present the development and clinical pilot study of an oxygen-sparing nasal reservoir cannula (OSNRC) for pediatric use in low-income settings. METHODS: (1) Pre-clinical development of a novel OSNRC using a simulated respiratory circuit with metabolic simulator and anatomically accurate face-airway models. Simulated breathing waveforms were designed based on airway resistance, lung compliance, respiratory rate, and tidal volume of spontaneous breathing for three disease conditions. (2) Pilot, randomized, controlled, non-blinded, cross-over study of the OSNRC vs standard nasal cannula (SNC) among children hospitalized with hypoxemic pneumonia in Uganda. Eight children were randomized to OSNRC followed by SNC, and eight were randomized to SNC followed by OSNRC. RESULTS: The laboratory simulation showed that the OSNRC provided the same or higher fraction of inspired oxygen at approximately 2.5-times lower flow rate compared to SNC. The flow savings ratio exhibited a linear relationship with the OSNRC volume to tidal volume ratio with a slope that varied with breathing waveforms. The range of performance from different breathing waveforms defined a performance envelope of the OSNRC. Two mask sizes (30 mL and 50 mL) provided sufficient coverage for patients between the 3rd and 97th percentile in our targeted age range. In the clinical pilot study, the rise in capillary blood pCO2 was similar in the OSNRC and SNC groups, suggesting that the OSNRC was not associated with CO2 retention. There were no significant differences between OSNRC and SNC with respect to clinical adverse events, lactate levels, pH, and SpO2. The OSNRC group had a higher mean SpO2 than the SNC group (adjusted mean difference, 1.4, 95% confidence interval 1.1 to 1.8), showing oxygen delivery enhancement. CONCLUSION: The OSNRC enhances oxygen delivery without causing CO2 retention and appears to be well-tolerated by pediatric patients. If safety, efficacy and tolerability are confirmed in larger trials, this device has the potential to optimize oxygen delivery in children in low-resource settings, reducing the global burden of pediatric pneumonia. TRIAL REGISTRATION: The trial was retrospectively registered (International Standard Registered Clinical/Social Study Number (ISRCTN): 15216845 ; Date of registration: 15 July 2020).

Oxygen insecurity and mortality in resource-constrained healthcare facilities in rural Kenya.

INTRODUCTION: Pneumonia is the leading cause of death globally in children. Supplemental oxygen reduces mortality but is not available in many low-resource settings. Inadequate power supply to drive oxygen concentrators is a major contributor to this failure. The objectives of our study were to (a) assess the availability of therapeutic oxygen; (b) evaluate the reliability of the electrical supply; and (c) investigate the effects of suboptimal oxygen delivery on patient outcomes in selected healthcare facilities in rural Kenya. MATERIALS AND METHODS: A cross-sectional descriptive study on oxygen availability and descriptive case series of Kenyan children and youth hospitalized with hypoxemia. RESULTS: Two of 11 facilities had no oxygen equipment and nine facilities had at least one concentrator or cylinder. Facilities had a median of seven power interruptions per week (range: 2-147). The median duration of the power outage was 17 minutes and the longest was more than 6 days. The median proportion of time without power was out 7% (range: 1%-58%). Fifty-seven patients hospitalized with hypoxemia (median oxygen saturation 85% [interquartile range {IQR}: 82-87]) were included in our case series. Patients received supplemental oxygen for a median duration of 4.6 hours (IQR: 3.0-7.8). Eighteen patients (32%) faced an oxygen interruption of the median duration of 11 minutes (IQR: 9-20). A back-up cylinder was used in 5/18 (28%) cases. The case fatality rate was 11/57 (19%). CONCLUSION: Mortality due to hypoxemia remains unacceptably high in low-resource healthcare facilities and may be associated with oxygen insecurity, related to lack of equipment and/or reliable power.