Clinical impact of preoperative inspiratory muscle training: We need further studies!

The effectiveness of prehabilitation interventions on biopsychosocial and service outcomes pre and post upper gastrointestinal surgery: a systematic review

PURPOSE

This review synthesised the evidence for the effect of prehabilitation interventions on biopsychosocial and service outcomes.

MATERIALS AND METHODS

A systematic review was conducted. 10 databases were searched to December 2023. Prospective experimental studies exploring prehabilitation interventions in adults undergoing upper gastrointestinal surgery were included. Prehabilitation was any preoperative intervention to improve physical or psychological outcomes. Included studies required a comparator group or alternative preoperative intervention as well as baseline, presurgical and postoperative assessment points. Study quality was assessed using the Cochrane risk of bias tool (v.2). Data synthesis was narrative (SWiM guidance).

RESULTS

6028 studies were screened, with 25 studies included. Prehabilitation interventions were: inspiratory muscle training (five studies n = 450); exercise (nine studies n = 683); psychological (one study n = 400); and nutritional (ten studies n = 487). High quality studies showed preoperative improvements in impairments directly targeted by the interventions. Generally, these did not translate into functional or postoperative improvements, but multimodal interventions were more promising.

CONCLUSION

Current evidence supports prehabilitation as safe to preserve or improve preoperative function. Heterogeneity in outcomes and variable study quality means definitive conclusions regarding interventions are not yet possible, limiting implementation. Agreement of clinical outcomes and cost effectiveness evaluation is required.

Preoperative respiratory muscle training reduces the risk of pulmonary complications and the length of hospital stay after cardiac surgery: a systematic review

QUESTIONS

What is the effect of preoperative respiratory muscle training (RMT) on the incidence of postoperative pulmonary complications (PPCs) after open cardiac surgery? What is the effect of RMT on the duration of mechanical ventilation, postoperative length of stay and respiratory muscle strength?

DESIGN

Systematic review of randomised trials with meta-analysis.

PARTICIPANTS

Adults undergoing elective open cardiac surgery.

INTERVENTION

The experimental groups received preoperative RMT and the comparison groups received no intervention.

OUTCOME MEASURES

The primary outcomes were PPCs, length of hospital stay, respiratory muscle strength, oxygenation and duration of mechanical ventilation. The methodological quality of studies was assessed using the PEDro scale and the overall certainty of the evidence was assessed using the GRADE approach.

RESULTS

Eight trials involving 696 participants were included. Compared with the control group, the respiratory training group had fewer PPCs (RR 0.51, 95% CI 0.38 to 0.70), less pneumonia (RR 0.44, 95% CI 0.25 to 0.78), shorter hospital stay (MD -1.7 days, 95% CI -2.4 to -1.1) and higher maximal inspiratory pressure values at the end of the training protocol (MD 12 cmH2O, 95% CI 8 to 16). The mechanical ventilation time was similar in both groups. The quality of evidence was high for pneumonia, length of hospital stay and maximal inspiratory pressure.

CONCLUSION

Preoperative RMT reduced the risk of PPCs and pneumonia after cardiac surgery. The training also improved the maximal inspiratory pressure and reduced hospital stay. The effects on PPCs were large enough to warrant use of RMT in this population.

REGISTRATION

CRD42021227779.

INSPIRA: study protocol for a randomized-controlled trial about the effect of spirometry-assisted preoperative inspiratory muscle training on postoperative complications in abdominal surgery

Background

Rehabilitation strategies after abdominal surgery enhance recovery and improve outcome. A cornerstone of rehabilitation is respiratory physiotherapy with inspiratory muscle training to enhance pulmonary function.

Pre-habilitation is the process of enhancing functional capacity before surgery in order to compensate for the stress of surgery and postoperative recovery. There is growing interest in deploying pre-habilitation interventions prior to surgery.

The aim of this study is to assess the impact of preoperative inspiratory muscle training on postoperative overall morbidity. The question is, whether inspiratory muscle training prior to elective abdominal surgery reduces the number of postoperative complications and their severity grade.

Methods

We describe a prospective randomized-controlled single-centre trial in a tertiary referral centre. The primary outcome is the Comprehensive Complication Index (CCI) at 90 days after surgery. The CCI expresses morbidity on a continuous numeric scale from 0 (no complication) to 100 (death) by weighing all postoperative complications according to the Clavien-Dindo classification for their respective severity.

In the intervention group, patients will be instructed by physiotherapists to perform inspiratory muscle training containing of 30 breaths twice a day for at least 2 weeks before surgery using Power®Breathe KHP2. Depending on the surgical schedule, training can be extended up to 6 weeks. In the control group, no preoperative inspiratory muscle training will be performed. After the operation, both groups receive the same physiotherapeutic support.

Discussion

Existing data about preoperative inspiratory muscle training on postoperative complications are ambiguous and study protocols are often lacking a clear design and a clearly defined endpoint. Most studies consist of multi-stage concepts, comprehensively supervised and long-term interventions, whose implementation in clinical practice is hardly possible. There is a clear need for randomized-controlled studies with a simple protocol that can be easily transferred into clinical practice. This study examines the effortless adjustment of the common respiratory physiotherapy from currently postoperative to preoperative. The external measurement by the device eliminates the diary listing of patients’ performances and allows the exercise adherence and thus the effect to be objectively recorded.

Trial registration

ClinicalTrials.govNCT04558151. Registered on September 15, 2020.