Overview
Postoperative respiratory failure (PORF) remains a critical driver of morbidity, mortality, and incremental care costs in surgical populations. Traditional escalation often involves invasive mechanical ventilation, which is associated with ventilator-associated pneumonia (VAP), prolonged intensive care unit (ICU) stays, and increased resource burden.
Description
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.
Eligibility
Inclusion criteria:
- Age above 18 years
- within 48 hours after major surgery
- PAO2/FIO2 less than 200
- Signs of respiratory distress and respiratory rate (RR) more than 25 cycles/minute
Exclusion Criteria:
- Age below 18 years
- Pregnant ladies
- Orofacial trauma or burns
- Active Gastrointestinal bleeding
