Management of Post-operative Respiratory Failure by Using NIV and High Velocity Nasal Insufflation (HVNI)

Noninvasive ventilation (NIV) and high-flow nasal cannula (HFNC) have both been shown to improve oxygen levels effectively and reduce the need for reintubation in various patient groups. However, head-to-head data in patients with obstructive or restrictive pulmonary function (PORF) are scarce.

This protocol employs a robust and scalable design to generate high-quality evidence, empower perioperative stakeholders, and optimize patient-centric respiratory strategies. We hypothesize that NIV will reduce 72-hour reintubation rates compared to HFNC, translating into shorter ICU stays and lower costs.

Methodology \& Operational Workflow

* Screening \& Consent Identify eligible patients in the post-anesthesia care unit (PACU) or ICU. Obtain informed consent from the patient or legal surrogate. * Baseline Assessment The baseline assessment includes demographics, comorbidities, and surgical data, as well as baseline arterial blood gases (ABG), vital signs, and comfort scores. * Randomization \& Initiation Allocate via a secure web-based randomization module. Initiate assigned respiratory support within 30 minutes of notification. * Monitoring \& Data Collection The patient is receiving continuous pulse oximetry and respiratory rate monitoring.

ABGs and fraction of inspired oxygen (FIO2) at 1 hour, 6 hours, and 24 hours. Comfort scores every six hours. Record interface-related adverse events.

\- Escalation Criteria The patient exhibits persistent partial arterial oxygen pressure/fraction of inspired oxygen ratio (PaO2/FiO2) levels of less than 100, even at maximal settings.

Hemodynamic instability occurs due to the use of new-onset vasopressors. Deterioration leading to invasive ventilation → classified as "reintubation."

* Weaning Protocol. Transition to standard oxygen therapy when the flow or pressure is minimal. * Follow-Up \& Discharge Track ICU length of stay (LOS), hospital LOS, and ventilation-free days (VFD). Keep a record of the 30-day survival rate and any readmissions. * Statistical Analysis Plan Primary Endpoint: Compare reintubation rates using a χ² test; report the risk difference and 95% confidence interval. * Missing Data: Multiple imputation for datasets with ≤ 5% missing data; sensitivity analysis for worst-case scenarios. * Interim Analysis: After 50% enrollment, the Data Safety and Monitoring Board (DSMB) reviews efficacy and futility, using O'Brien-Fleming boundaries.