Cardiopulmonary bypass and internal thoracic artery: Can roller or centrifugal pumps change vascular reactivity of the graft? The IPITA study: A randomized controlled clinical trial

Inspiratory muscle training and functional capacity following coronary artery bypass grafting in high-risk patients: A pilot randomized and controlled trial

Background

Coronary artery bypass graft (CABG) surgery is associated with worsened functional capacity, pulmonary complications, and increased length of hospital stay. These negative effects are exacerbated in patients who are at high risk of post-operative (PO) pulmonary complications before CABG. Inspiratory muscle training (IMT) has been shown to benefit CABG patients in their recovery process. However, in high-risk patients, there is little evidence to support the post-operative implementation of IMT for purposes of faster recovery.

Aim

The aim of the study was to test the hypothesis that IMT improves the functional capacity, pulmonary complications, and length of hospital stay in patients prone to pulmonary complications who had undergone CABG.

Methods

This is a pilot clinical trial carried out with patients at high risk for pulmonary complications in the PO phase. In the pre-operative period, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and 6-min walk test (6MWT) were determined and administered. On the first PO day, patients were divided into two groups: A control group (CG) that received routine intervention and an IMT group that, in addition to routine care, was subjected to an IMT protocol until hospital discharge. On the day of discharge, the patients were reassessed with respect to ventilatory muscle strength, functional capacity, PO complications, and length of stay.

Results

Twenty-nine patients were evaluated, 15 in the CG and 14 in the IMT group. No significant differences were observed in relation to MIP (difference between the mean of -7 cmH₂O; 95% CI = -16.52-2.52), MEP (difference between the mean of -7cm H₂O; 95% CI = -15.39-1.39), and in the 6MWT (difference between the mean of -9 m; 95% CI = -43.71-25.71). There was a decrease in the length of stay in the IMT group compared to the CG (9 ± 3 vs. 12 ± 4 days; P = 0.04). The IMT group had a lower rate of atelectasis and pneumonia.

Conclusion

IMT does not minimize the loss of functional capacity, but it reduces pulmonary complications and the length of stay of patients undergoing CABG who are preoperatively at a high risk of pulmonary complications.

Relevance for Patients

The increase in ventilatory muscle strength, associated with IMT, can reduce PO pulmonary complications, resulting in shorter hospital stays, and improved quality of life.

The use of a vascular occlusion test combined with near-infrared spectroscopy in perioperative care: a systematic review

In the perioperative phase oxygen delivery and consumption can be influenced by different factors, i.e. type of surgery, anesthetic and cardiovascular drugs, or fluids. By combining near-infrared spectroscopy (NIRS) monitoring of regional tissue oxygen saturation (StO₂) with an ischemic provocation test, the vascular occlusion test (VOT), local tissue oxygen consumption and vascular reactivity at the microcirculatory level can be assessed. This systematic review aims to give an overview of the clinical information that VOT-derived NIRS values can provide in the perioperative period. After performing a systematic literature search, we included 29 articles. It was not possible to perform a meta-analysis because of the lack of comparable data and the observational nature of the majority of the included articles. We have clustered the found articles in two groups: non-cardiac surgery and cardiac surgery. We found that VOT-derived NIRS values show a wide variability and are influenced by the effects of anesthetics, cardiovascular drugs, fluids, and by the type of surgery. Additionally, deviations in VOT-derived NIRS values are also associated with adverse patients' outcomes, such as postoperative complications, prolonged mechanical ventilation and prolonged hospital length of stay. However, given the variability in VOT-derived NIRS values, clinical applicability remains elusive. Future clinical interventional trials might provide additional insight into the potential of VOT associated with NIRS to optimize perioperative care by targeting specific interventions to optimize the function of the microvasculature.