Background: Diagnostic and interventional flexible bronchoscopy (FB) is increasingly utilized in complex and high-risk patients. Patients are often sedated for comfort and procedure facilitation and hypoxia is commonly observed in this setting. We hypothesized that high-flow nasal oxygen (HFNO) would reduce the incidence of patients experiencing oxygen desaturation. Methods: In this randomized controlled trial, postlung transplant patients booked for FB with transbronchial lung biopsy were assigned to either HFNO or low-flow nasal oxygen (LFNO). The patient and bronchoscopist were blinded to group allocation. The primary endpoint was the proportion of patients experiencing mild desaturation [peripheral oxygen saturation (SpO2)<94%]. Secondary endpoints included desaturation (SpO2<90%), the number of airway interventions required and procedure interruptions, the duration of oxygen desaturation and patient, bronchoscopist and anesthesiologist satisfaction scores. Results: The trial analyzed data from 76 patients (LFNO, n=39; HFNO, n=37). HFNO reduced the proportion of patients experiencing SpO2<94% (43.2% vs. 89.7%, P<0.001) and SpO2<90% (16.2% vs. 69.2%, P<0.001). The FB was interrupted 11 times in 9 patients in the LFNO group, whereas there were no interruptions in the HFNO group. There were no differences in patient and bronchoscopist satisfaction scores between groups, anesthesiologists had higher satisfaction scores when using HFNO (P<0.001). Conclusion: Hypoxia occurred less commonly in postlung transplant patients receiving HFNO during FB. Further studies are warranted in other high-risk populations undergoing longer duration FB.

Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine.

Significant hypotension after induction of general anesthesia is common and has the potential for serious complications. This study aimed to determine if pre-operative heart rate variability (HRV) was associated with post-induction hypotension in patients undergoing major abdominal surgery. Patients undergoing semi-elective major abdominal surgery were consecutively recruited during pre-admission clinic assessment. Exclusion criteria included cardiac conduction disease, arrhythmias or severe liver or renal disease. Ten minutes of electrocardiogram at 1024 Hz were recorded a median of 3 days pre-operatively. Pre-operative HRV parameters were compared in patients who experienced significant hypotension (fall in systolic and mean arterial pressure (MAP) >30% baseline and MAP ≤60 mmHg) versus those who remained haemodynamically stable after induction of general anesthesia with propofol and fentanyl. Patients who experienced hypotension after general anesthesia induction had significantly lower pre-operative HRV (SDNN 16 vs. 37 ms, p < 0.001), reduced spectral power (total power 262 vs. 1236 ms, p = 0.002) and reduced correlation dimension, a measure of signal complexity (0.11 vs. 2.13, p < 0.001). Hypotension occurred relatively frequently in our cohort and was associated with a higher ASA grade (36 vs. 6% ASA 3, p = 0.036), hence post-induction hypotension and lower HRV may be associated with severity of illness or poor physiological reserve. Pre-operative HRV was a useful screening tool in identifying patients undergoing major abdominal surgery who were at risk of haemodynamic instability after anesthesia induction.