This was a prospective, randomised, open-label, blinded-endpoint trial conducted in a single academic centre in the Netherlands.
Whilst physician-led inter-hospital transfers of level-3 patients are the norm in Europe, it is not borne out in the evidence that this confers a benefit. The authors proposed that a transfer-trained critical care nurse-led escort would be non-inferior, as measured by the primary outcome of the number of patients experiencing critical events (either clinical or technical). Estimating the incidence of such events at 0-1%, and accepting an upper limit of two-sided 90% confidence interval below a non-inferiority margin of 3%, around 150 patients were included in each arm.
The majority of transfers were performed owing to lack of availability of beds. Baseline characteristics were similar.
Clinical critical events (in particular, desaturations of 10% for 10 minutes, alterations in blood pressure of 20 mmHg for 10 minutes, and hypothermia <36oC), as measured electronically, were significantly higher than expected in both groups, with an incidence of around 16%. For this reason, the authors were unable to establish non-inferiority. They propose that the high incidence of clinical critical events may be due to their electronic measurement, in contrast to the self-reporting utilised in previous studies.
The study may not be immediately relevant to ourselves, as it was performed by a specialist retrieval team conducting 350 transfers per year; the study was arguably flawed by its selection of primary outcome and calculation of expected events; and, despite being published this year, relates to a study period between 2006-8.
Summary by Dr Steve Cole
A Second Opinion
Here’s what they thought of this paper over at The Bottom Line