Transcutaneous carbon dioxide monitoring in children undergoing rigid bronchoscopy: a prospective blinded observational study.

Purpose: Anesthetic management during rigid bronchoscopy in children can be challenging, and continuous end-tidal carbon dioxide (EtCO₂) monitoring is often unachievable. Transcutaneous carbon dioxide (TcCO₂) monitoring is strongly correlated with the partial pressure of carbon dioxide (PaCO₂) and EtCO₂. We aimed to investigate the incidence of hypercapnia in children undergoing rigid bronchoscopy.

Methods: We enrolled patients aged < 18 yr scheduled for rigid bronchoscopy in a prospective observational study. We recorded TcCO₂ values from anesthesia induction to the postanesthesia care unit (PACU) stay. We ended monitoring when TcCO₂ reached values ≤ 50 mm Hg. The operating room (OR) team was blinded to the TcCO₂. The outcome of primary interest was the incidence of hypercapnia (TcCO₂ > 50 mm Hg) in the OR. Other outcomes were the incidences of hypercapnia in the PACU and severe hypercapnia (TcCO₂ > 90 mm Hg), factors possibly related to hypercapnia (patient, surgery, or anesthesia factors), and the incidence of perioperative adverse events.

Results: A total of 30 patients were enrolled. The median [interquartile range (IQR)] age was 3.5 [1.5-8.0] yr. The incidence of hypercapnia was 100% in the OR and 60% in the PACU. Five cases (17%) presented with severe hypercapnia in the OR. The highest median [IQR] TcCO₂ was 69 [61-79] mm Hg. The most common adverse event was oxygen desaturation (57%, 17/30). Patients with severe hypercapnia had long stays in the PACU.

Conclusion: Hypercapnia was a frequent event in children undergoing rigid bronchoscopy and severe hypercapnia was associated with a long PACU stay. Further studies are needed to assess the utility of TcCO₂ monitoring in guiding ventilatory interventions during these cases.