Rationalising arterial blood gas sampling analysis in the intensive care unit: A before-and-after study

Arterial blood gas (ABG) sampling is a frequent intensive care unit investigation with associated costs and labour burden. However, frequency of ABG sampling is not evidence based, and its use could be rationalised. Education strategies and other quality improvement methods can likely reduce ABG sampling, reducing cost, saving clinical time, and limiting the volume of blood drawn.

The aim of this study was to determine whether a multimodal intervention would reduce unnecessary ABG sampling.

A single-centre before-and-after study was conducted from August 2021 to July 2022 in a 48-bed quaternary Australian intensive care unit. A multimodal intervention, including a visual cue, education sessions, and a clinical decision support tool, was introduced over 6 months. Data were compared between a 3-month preintervention and a 3-month postintervention period. Data were collected on baseline patient demographics, illness severity, admission diagnosis, length of stay, mortality, and the number of ABG samples collected. Analysis of changes in the blood volume drawn, clinical time required, and total cost were derived from simple calculations using the numbers of ABG samples analysed.

The study included 1130 patients. Baseline variables in the preintervention and postintervention cohorts were comparable. The intervention was associated with nearly a 40% reduction in the rate of sampling (incident rate reduction: 0.61, 95% confidence interval: 0.54-0.70). This would yield an aggregate saving approximating 86 L of blood, 2400 h of clinical workload, and an estimated cost of $AUD 39 per patient/day.

A multimodal intervention to rationalise investigations reduced ABG sampling rates. The magnitude of this reduction confers notable reductions in the volume of blood drawn, repurposed clinical time, and financial savings.