Use of heart rate variability to assess functional capacity in multimodal rehabilitation programs in adult surgery: PreANI Study Protocol.

Abstract

Background and objectives: Despite the implementation of multimodal rehabilitation programs, postoperative complications are common in some surgeries, and patient recovery is not as rapid as expected. This study was designed to evaluate whether postoperative outcomes can be improved by assessing preoperative functional reserve and frailty on the basis of heart rate variability, specifically Energy (SDNN) and the ANIm (HFnu) value, in patients following prehabilitation programs.

Material and method: Prospective, observational cohort study that will include patients undergoing colorectal oncology surgery within a multimodal rehabilitation program. Patients will be monitored with the ANI device at 2 time points: initial (first pre-anaesthesia consultation, 4 weeks before surgery) and second consultation (1 week before surgery). Data will be collected on heart rate variability, energy, and ANIm values, cardiopulmonary exercise test scores, and other parameters.

Results: We will analyse the correlation between heart rate variability indices and current functional assessment parameters, physiological reserve, and frailty (ASA scale, 6-minute walk test, MUST scale, and Clinical Frailty Scale). Our hypothesis is that higher energy levels (SDNN) will correlate with better postoperative outcomes, fewer complications, and shorter hospital stays.

Conclusions: Statistical analysis will respect all principles of confidentiality and privacy. The results will be published in peer-reviewed journals. This study aims to provide a new tool for assessing frailty and functional reserve in surgical patients as a means of improving prehabilitation programs and postoperative outcomes.