PREVENTION OF PRESSURE ULCERS IN NASAL BRIDGE DURING NON-INVASIVE MECHANICAL VENTILATION. DISCUSSION OF RESULTS.

Editor,

We would like to discuss the results achieved in the study by Bishopp et al. recently published in Ulster Medical Journal in which strategies for skin care during non-invasive mechanical ventilation were suggested.1 The discussion of this study refers to a limited protective benefit of hyperoxygenated fatty acids in a study carried out by our team and also suggested that our sample was too limited to draw conclusions.2

We would like to refute the suggestion that our study, “Preventing facial pressure in patients under non-invasive mechanical ventilation: a randomized control trial” has a small sample size.2 Our study had a methodology with calculation of statistical sample size 3, declared in the article and in previous protocols, by a previous piloting with 40 patients (10 in each group). The piloting allowed a pre-analysis for the size calculation of the effect estimated in 15.8%.

In the case of our clinical trial, the result of the number of the sample calculated is 152 patients in total among the four study groups, making replacement of the losses as can be seen in Fig. 1 of our article. The sample has been calculated so that the results can be considered, assuming the size of the effect described, a statistical power of 80% (β = 0.20) and a confidence level of 95% (α = 0.05).

For all these reasons, we consider it important to emphasise our results and suggest care strategies based on the application of hyperoxygenated fatty acids and /or essential oils every 4-6 hours in the contact areas of the interface during non-invasive mechanical ventilation, following advice in recent results published on the same line. 2,4