Low-flow oxygen therapy in intensive care: an observational study.

Abstract

There is scant published evidence that explains how ICU nurses' manage low-flow oxygen therapy; and, hence little is known about how low-flow oxygen therapy is delivered on a daily basis.The aims of this study were first to observe how ICU nurses' manage low-flow oxygen therapy and then to compare observed nursing practice on the management of oxygen therapy with patients' documented measures of oxygen saturation (SpO2) and respiratory rate (RR).From May to July 2009, eight 2h observation periods were conducted in one ICU of a metropolitan hospital in Melbourne, Victoria. Data were collected at using a structured observation tool, field notes and chart review. Quantitative data were analysed using descriptive and frequency statistics, and textual data were reviewed using a content analysis procedure.Over the 16 h of observed nursing practice, there were 96 points of measurement involving 16 patients and 16 ICU nurses. The management of low-flow oxygen therapy varied between nurses and data revealed that nurses did not always promote effective oxygenation. Documented SpO2 was 98.0% (SD 2.8%) and observed SpO2 was 96.3% (SD 1.8%). Documented RR was 19.6 breaths/min (SD 3.5) and observed RR was 21.0 breaths/min (SD 16.8). Episodes of hypoxaemia and tachypnoea occurred while patients were receiving oxygen and nurses did not always respond appropriately.ICU nurses' management of low-flow oxygen therapy was suboptimal and documentation of oxygenation and respiratory rate was inaccurate. Further exploration of how ICU nurses manage low-flow oxygen therapy is a necessary prelude to the conduct of interventional studies and the development of better guidance to support low-flow oxygen therapy in the ICU.