Acute physiological effects of N95 respirator use on gastroenterologists performing simulated colonoscopy.

Khalid, Asif; Romutis, Stephanie; Ibinson, Jonathan; Thomas, Christopher; Myint, Alex; Dueker, Jeffrey; Johnston, Elyse; Kreiss, Christianna; Kingsley, Michael; Skef, Wasseem; Vipperla, Kishore; McGrath, Kevin; Phillips, Anna Evans; Das, Rohit; Fasanella, Kenneth; Ibinson, James

BACKGROUND AND AIMS During the SARS-CoV-2 pandemic, N95 filtering facepiece respirator (FFR) use is required while performing aerosol-generating procedures. We studied the physiological effects of N95 FFR use in a cohort of gastroenterologists performing simulated colonoscopies. METHODS Data collection and comparisons included (1) symptoms and change in vital signs in 12 gastroenterologists performing simulated colonoscopy for 60 minutes while wearing a surgical mask (SM) and face-shield (FS); N95 FFR, SM and FS; and powered air purifying respirator (PAPR), and (2) respiratory belt plethysmography and continuous EKG frequency-based heart rate variability indices including very low frequency power (measures intracardiac sympathetic tone) and low frequency to high frequency ratios (intracardiac sympathetic to vagal ratio) in 11 gastroenterologists performing simulated colonoscopy while wearing a SM (15 minutes), N95 FFR and SM (60 minutes), and SM (15 minutes) in rapid sequence. RESULTS Ten of 12 (83%) gastroenterologists reported symptoms with N95 FFR use, most commonly breathing difficulty, frustration, fatigue, and headache. Nine (75%) of these gastroenterologists had associated significant heart rate elevation. Respiratory peak to trough measurement showed a significant increase (F(2)=7.543, p=0.004) during the N95 FFR stage, which resolved after removal of N95 FFR. Although not statistically different, all gastroenterologists showed a decrease in sympathetic to vagal ratio and an increase in intracardiac sympathetic effect in the N95 FFR stage. PAPR use was better tolerated but associated with headache and elevated heart rate in 4 (33%) gastroenterologists. CONCLUSIONS N95 FFR use by gastroenterologists is associated with development of acute physiological changes and symptoms.