Paediatrics (RCH) - Theses
Permanent URI for this collection
Search Results
1 - 3 of 3
-
ItemImproving oxygen therapy for children and newborns in Nigerian hospitals( 2018)Oxygen is a long-established medical therapy that can be life-saving for severely ill children admitted to hospital. Effective provision of oxygen to patients requires a multifaceted system that involves technical, clinical, supply chain, financing, and other managerial and policy elements. However, this system is currently difficult to achieve in many low-resource settings resulting in poor access to, and use of, oxygen and subsequent excess mortality. Previous work has shown that improved hospital oxygen systems can improve patient access to oxygen therapy and reduce inpatient case fatality rates from childhood pneumonia. However, studies have shown variable impact in different settings due to contextual factors that are not well understood. In addition, the burden of hypoxaemia and impact of oxygen on conditions other than pneumonia is unclear – particularly in the large neonatal population. This study aimed to understand how to improve oxygen systems in particular contexts, and generate evidence to support the scale-up of effective oxygen systems in Nigeria and globally. My realist review of past oxygen projects developed a theoretical framework describing how improved oxygen systems could improve clinical outcomes in particular contexts – highlighting the interaction between efforts to improve oxygen access and the clinical use of oxygen. My oxygen needs assessment in 12 secondary-level Nigerian hospitals provided detailed data on existing oxygen systems – highlighting the impact of poor power supplies, weak maintenance systems, and lack of pulse oximetry. My prospective cohort study provided new data on the epidemiology of hypoxaemia in the Nigerian context. This study showed high prevalence of hypoxaemia among admitted children and neonates with a range of conditions, highlighted the strong association between hypoxaemia and death, and demonstrated poor accuracy of clinical signs to predict hypoxaemia (particularly for children with non-respiratory conditions). My mixed-methods realist evaluation identified how pulse oximetry could be most effectively adopted into routine paediatric and neonatal care – highlighting the role of key influencers to model behaviour, practical training and ongoing encouragement, personal experience of benefit, and the reasons why nurses valued pulse oximetry. My stepped wedge trial evaluated the effect of our intervention (improved oxygen system) on clinical outcomes and care practices. This study demonstrated mortality benefit for children admitted with pneumonia, and suggested that the introduction of pulse oximetry generated most of this benefit by stimulating better use of existing oxygen supplies. We found no mortality benefit for children with other conditions or neonates, and detected an unexpected trend towards higher mortality in the “full oxygen system” period compared to the “pulse oximetry period” for neonates. Post-hoc analysis tested some potential explanatory theories for these findings – highlighting the effects of pre-existing oxygen access and external factors. In conclusion, improving oxygen systems is complex. The studies contained in this thesis have helped fill evidence gaps that are hindering oxygen policy and planning decision-making in Nigeria and globally. They have directly informed national and global policies and program planning.
-
ItemThe burden of acute respiratory infections in Indonesian children and the association with vitamin D deficiency( 2018)INTRODUCTION: Vitamin D supplementation for pregnant women and young children is a controversial topic. It has been postulated that vitamin D is a potent immunomodulator against numerous infectious diseases including acute respiratory infections (ARI). However, evidence for the role of vitamin D supplementation for ARI prevention is inconclusive. While vitamin D deficiency (below 50 nmol/L) in children under five years old has been associated with a higher risk of ARI and linked with pneumonia hospitalisation, including treatment failure and admission to intensive care unit, findings have not been consistent across studies. Further, it is unknown whether vitamin D deficiency is likely to contribute to the burden of child pneumonia in Indonesia. Limited data are available on: 1) the current burden of ARI in infants < 12 months old; 2) the prevalence of vitamin D deficiency in infants and young children; 3) the association between vitamin D deficiency and subsequent development of ARI in infants; and 4) the association with severity of pneumonia in children under five years of age admitted to hospital. The primary aim of this doctoral work was to describe the burden of ARI in Indonesian children and to evaluate the association with vitamin D deficiency. METHODS: Two studies were conducted concurrently as part of the Indonesian Pneumonia and Vitamin D Study (IPAD study), in two regions of Yogyakarta province, Indonesia. The first study was the Community IPAD study, a prospective birth cohort study of healthy newborns born in nine selected Primary Health Care centres and five private practice clinics and followed for 12 months for episodes of ARI, including WHO-defined pneumonia. Vitamin D status was measured at birth and at six months of age. Parents were interviewed about risk factors associated with ARI and vitamin D status. The association between vitamin D status at birth and at six months of age, and with episodes of ARI (pneumonia and non-pneumonia) in the subsequent 12 months and six months, respectively, was evaluated. The second study was the Hospital IPAD study, a cross-sectional study of children aged 2 – 59 months old who were hospitalised with pneumonia. Vitamin D status was measured on admission and was evaluated for its association with pneumonia severity indicators including danger signs, hypoxaemia (SpO2 <90%), duration of hospital stay, intensive care unit admission and mortality. Parents were interviewed for risk factors associated with severe pneumonia and vitamin D status. Serum 25-hydroxycholecalciferol was analysed with liquid chromatography tandem mass spectroscopy assay for both studies. Vitamin D deficiency was defined as vitamin D level below 50 nmol/L. Univariate and multivariate Cox proportional hazard regression, linear regression and logistic regression were performed in STATA version 12, as appropriate. RESULTS: From December 2015 to December 2017, 422 newborns were recruited to the Community IPAD study with 22 participants (5%) lost to follow-up by the end of study period. The incidence of all ARI in infants <12 months old in the community was 3.89 (95% CI 3.70 – 4.08) episodes per child year observation (CYO), and there was a high incidence of pneumonia of 0.25 (95% CI 0.21 – 0.30) episodes per CYO. The incidence of pneumonia was highest between 9 to 12 months of age with an incidence rate of 0.39 (95% CI 0.29 – 0.53) episodes per CYO. In multivariate analyses, male gender (HR 2.17, 95% CI: 1.38 – 3.45) and exposure to paternal smoking (HR 1.70, 95% CI 1.09 – 2.64) were independently associated with an increased risk for pneumonia in infancy whereas household crowding (HR 2.59, 95% CI: 1.16 – 5.76) and an older sibling aged younger than two years (HR 3.53, 95% CI: 1.36 – 9.17) were independently associated with a pneumonia episode before six months of age. There was a very high prevalence of vitamin D deficiency at birth, with 90% of 344 participants deficient, compared to 13% of 255 at six months of age. Infants who were exclusively breast fed for six months were at increased risk of vitamin D deficiency at six months (Adjusted OR 2.64, 95%: 1.07 – 6.49). A higher exposure to sunlight was significantly associated with a lower prevalence of vitamin D deficiency. Participants with vitamin D deficiency at birth were more likely to have six or more episodes of ARI non-pneumonia (Adjusted OR 4.48, 95% CI :1.04 – 19.34). However, we did not observe a significant association between vitamin D status at birth and at 6 months of age with the subsequent incidence of pneumonia episodes. From February 2016 to July 2017, 133 participants were recruited to the Hospital IPAD study. One in every five participants was vitamin D deficient, but vitamin D deficiency was not associated with severity of pneumonia, as indicated by hypoxaemia on admission (OR 1.19, 95% CI: 0.35– 4.02), cyanosis (OR 4.50, 95% CI: 0.85 – 23.80) or prolonged hospitalisation (OR 1.12, 95% CI: 0.46 – 2.75). CONCLUSION: This study found a high incidence of pneumonia in Indonesian infants consistent with previous global estimates, with established risk factors associated with pneumonia such as male sex, household crowding and exposure to cigarette smoking. The high prevalence of vitamin D deficiency in newborns in this study would suggest that interventions – antenatal and postnatal – could be considered that would improve vitamin D status in infants, such as safe sun exposure in pregnant women and infants. The association between vitamin D deficiency and more frequent ARI non-pneumonia was evident in this study. Our findings of no association between vitamin D deficiency and the subsequent development of pneumonia or with severity of hospitalised pneumonia have added to the ongoing uncertainty that has arisen from RCTs and meta-analyses. Therefore, further studies of the association between vitamin D deficiency and pneumonia, and stronger evidence of benefit, such as from randomised trials of vitamin D supplementation, are required before justification of vitamin D supplementation of infants or their mothers to prevent pneumonia can be considered and recommended as public health policy. These studies need to have a rigorous case-ascertainment method, standardised ARI outcomes and an adequate sample size including episodes of severe disease in alignment with clear public health and clinical goals. There was a lack of statistical power to determine an association between vitamin D deficiency and severe disease in the hospital study, and so larger studies of children with severe disease are required to provide conclusive evidence.
-
ItemChildhood pneumonia and hypoxaemia in an urban diarrhoeal hospital, Dhaka, Bangladesh( 2010)The aim of this prospective cohort study was to evaluate clinical and socio-demographic predictors of pneumonia, deaths from pneumonia, and hypoxaemia in children. All under-five children who were admitted to the special care ward of ICDDR,B during September 2007-December 2007 were enrolled. Children sleeping in a bare bed and those having parents/caregivers with poor knowledge were at risk of pneumonia. Children with severe malnutrition, hypoxaemia, or severe sepsis were at higher risk of death. Chest wall-indrawing was the best predictor of hypoxaemia.