| Dissertation |
Thesis (M.D. Research) --NUI, 2013 at Department of Anaesthesis, UCC. |
| Summary |
Assessing intravascular volume status in children is challenging and guided by little evidence. The ability to accurately predict a significant cardiac output response to fluid administration, volume responsiveness (VR), would be clinically valuable. Our aim was to investigate, in children, non-invasive indices of VR derived from the variations induced by mechanical ventilation in the pulse oximeter plethysmograph (POP) and the arterial pulse pressure (PP) waveforms. These so-called dynamic indicators have formerly been demonstrated in adults to accurately predict VR. Our first study examined the relationship between respiratory variations in the POP and PP waveforms and to assess the feasibility of analysis of the POP waveform in small children. We undertook this study in both the intensive care and operating theatre environments. Our results demonstrated that even in very sick children that the POP waveform can accurately be extracted and that the PP and POP variations correlate closely. Our second study assessed the ability of the dynamic indices derived from the PP and POP waveforms to predict VR and compared these to cardiac filling pressures, indices traditionally held to predict VR in children. We examined these markers in a population of children in the cardiac catheterization laboratory. Our results demonstrated, that dynamic indicators did not predict VR. In addition, neither cardiac filling pressures nor their trends were useful to predict VR. The results of this body of work contrast with adult studies, which have demonstrated that dynamic indicators are the gold standard for prediction of VR. The reason for this disconnect is probably due to differences in paediatric cardio-respiratory interactions. The continuing recommendation for using cardiac filling pressures to assess volume status in children should, in the light of our results, be reconsidered. |
| Subject |
Pediatric anesthesia.
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| Collection |
Theses Masters (Research)
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Theses Anaesthesia and Intensive Care Medicine Department
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| Description |
234 p. ; 30 cm. |
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