Persisting diaphragmatic dysfunction (DD) for more than 24 hours after thoracic surgery is associated with higher rates of pulmonary complications and prolonged intensive care unit stays. Despite advances in less invasive techniques, the incidence of DD remains significant, affecting ~55%–68% of patients after video-assisted thoracoscopic surgery (VATS). Non-intubated VATS (NIVATS) has gained popularity for its safety, but its impact on outcomes, particularly DD, remains unclear. We aim to determine the incidence of DD following NIVATS in adult patients.

The DYNASTY (Diaphragmatic dYsfunction after Non-intubated video ASsisted Thoracic surgerY) study is a prospective, single-centre, single-arm observational study including 100 adult patients undergoing NIVATS for minor elective thoracoscopic procedures. Diaphragmatic function is assessed using bedside ultrasound preoperatively (baseline) and at 2 and 24 hours postoperatively. The primary outcome is the incidence of DD at 24 hours (defined as diaphragmatic excursion ≤10 mm on quiet breathing). Secondary outcomes include the incidence of postoperative respiratory complications (eg, pneumonia, acute chronic obstructive pulmonary disease exacerbation) and their association with DD. Statistical analyses will estimate DD incidence with 95% CIs and employ multivariable logistic regression to identify predictors of DD, adjusting for potential confounders.

The study protocol was approved by an institutional ethics committee (ID 2024-A009121-45), and all participants will provide written informed consent. Results will be disseminated through peer-reviewed publications and conference presentations. De-identified data will be made available on reasonable request, and the trial registry will be updated with data availability in line with International Committee of Medical Journal Editors (ICMJE) recommendations.

NCT06486168.