In severe cases after craniotomy, tracheal intubation is often required, and the removal of tracheal intubation presents certain risks and challenges. Premature removal of the tracheal intubation can lead to failure of extubation and increased proportion of re-intubation, resulting in increased risk of airway injury and hospital-acquired pneumonia, resulting in prolonged hospital stay and even adverse effects on neurological outcomes and mortality. However, delayed extubation can also lead to an increased risk of hospital acquired pneumonia, affecting early recovery and neurological recovery. It can be seen that the accurate evaluation of the possibility of tracheal intubation and the appropriate timing can have a greater impact on the prognosis of patients after craniotomy. However, there are currently no relevant standards or guidelines to guide clinical work. Previous studies have shown that for general critically ill patients, Peak cough flow (PCF) can play a certain role in predicting tracheal intubation, but the results of each study are not consistent. The predictive value of PCF for tracheal intubation and extubation in patients after craniotomy is less relevant. This study intends to use Pneumotachograph to measure the active and passive PCF of patients with extubation, to explore the predictive value of PCF for tracheal intubation after craniotomy, and to provide guidance for the development of clinical extubation decisions.

The objection of this study is to evaluate the preditive value of PCF for endotracheal extubation in patients undergoing craniotomy. For patients who met the inclusion criteria, the PCF value will be measured before the removal of entracheal tubes, and the predictive value of PCF will be evaluated by ROC curves, as will as the cut-off value of PCF.

According to state of consciousness, patients will be grouped as consciousness and unconsciousness group, and the predictive value of PCF for endotracheal extubation will be evaluated seprately in both groups. For patients with disturbance of consciousness, only passive PCF value will be measured. For lucid patients, inaddition to passive PCF value, the voluntary PCF value will also be measured.

Inclusion Criteria:

• Age ≥ 18 years
• Post- craniotomy
• ICU LOS ≥ 24h

Exclusion Criteria:

• no extubation attempt during the ICU stay;
• underwent tracheostomy without extubation attempt;
• pregnant or lactating women;
• enrolled in other clinical trials;
• declined to participate in the study.

Patients admitted into ICU ward after craniotomy will be screened. Those ones meeting the including criteria will be included. patients would be grouped by their extubation outcomes.

Data sets generated during the current study are available from the first author on reasonable request.

June to December 2025

It is necessary to provide materials related to the purpose of the data and the usage plan, and sign a data sharing agreement. In addition, the use of the data is subject to the approval of the Ethics Committee of our hospital. The first author can be contacted by email.