# A novel nomogram for predicting prolonged mechanical ventilation after acute type A aortic dissection surgery: a retrospective study investigating the impact of ventilation duration on postoperative outcomes

## TL;DR

This study developed a new tool to predict prolonged mechanical ventilation after aortic dissection surgery, which can help improve patient outcomes.

## Contribution

A novel and validated nomogram was created to predict prolonged mechanical ventilation after ATAAD surgery.

## Key findings

- Prolonged mechanical ventilation for 72 hours or more was significantly associated with higher short-term mortality.
- The nomogram effectively predicted PMV using risk factors like age, preoperative cerebral ischemia, and intraoperative transfusion.
- Early extubation within 72 hours is crucial for better postoperative outcomes in ATAAD patients.

## Abstract

Acute type A aortic dissection (ATAAD) is a devastating cardiovascular disease with extraordinary morbidity and mortality. Prolonged mechanical ventilation (PMV) is a common complication following ATAAD surgery, leading to adverse outcomes. This study aimed to investigate the correlation between mechanical ventilation time (MVT) and prognosis and to devise a nomogram for predicting PMV after ATAAD surgery.

This retrospective study enrolled 1049 ATAAD patients from 2011 to 2019. Subgroups were divided into < 12 h, 12 h to < 24 h, 24 h to < 48 h, 48 h to < 72 h, and ≥ 72 h according to MVT. Clinical characteristics and outcomes were compared among the groups. Using multivariable logistic regression analyses, we investigated the relationship between each stratification of MVT and mortality. A nomogram was constructed based on the refined multivariable logistic regression model for predicting PMV.

The total mortality was 11.8% (124/1049). The results showed that the groups with MVT 48 h to < 72 h and ≥ 72 h had significantly higher operative mortality compared to other MVT categories. Multivariate logistic regression analysis showed that MVT ≥72 h was significantly associated with higher short-term mortality. Thus, a nomogram was presented to elucidate the association between PMV (MVT ≥72 h) and risk factors including advanced age, preoperative cerebral ischemia, ascending aorta replacement, concomitant coronary artery bypass grafting (CABG), longer cardiopulmonary bypass (CPB), and large-volume intraoperative fresh frozen plasma (FFP) transfusion. The nomogram exhibited strong predictive performance upon validation.

Safely extubating patients within 72 h after ATAAD surgery is crucial for achieving favorable outcomes. The developed and validated nomogram provides a valuable tool for predicting PMV and optimizing postoperative care to improve patient prognosis. This novel nomogram has the potential to guide clinical decision-making and resource allocation in the management of ATAAD patients.

Prolonged mechanical ventilation (PMV) is a common complication following ATAAD surgery, leading to adverse outcomes.

Safely extubating patients within 72 hours after ATAAD surgery is crucial for achieving favourable outcomes.

A novel, validated nomogram incorporating risk factors such as age, comorbidities and intraoperative factors predicts PMV after ATAAD surgery, aiding clinical decision-making and optimizing postoperative care.