Does capnography improve safety in moderate-deep sedation for gastrointestinal endoscopic procedures provided by anaesthesiologists? A prospective cohort study

Abstract

This study aimed to determine whether the use of capnography reduces the incidence of respiratory and cardiovascular adverse events during procedural sedation and analgesia (PSA) for gastrointestinal endoscopic procedures (GEP) provided by experienced anaesthesiologists. A prospective cohort study was conducted, including patients undergoing GEP under PSA. Patients were divided in two groups: Group A (pulse oximetry) and Group B (capnography with Capnostream^™ monitor plus pulse oximetry). Interventions undertaken to resolve hypoxaemia, airway obstruction, or apnoea were recorded. Age, comorbidities, ASA Classification, sedative drugs, respiratory and cardiovascular adverse events, recovery Aldrete Scale value, and patient satisfaction were also recorded. Both parametric and non-parametric tests were applied. A total of 1,146 patients were included: Group A, n = 538, and Group B, n = 608. Diagnostic colonoscopy was the most frecuent procedure (49.7%), followed by diagnostic gastroscopy (22.5%) and therapeutic colonoscopy (22.2%). Apnoea < 60 s was detected only in patients monitored with capnography (35.4% vs. 0%, p < 0.000). The use of capnography significantly reduced the incidence of moderate hypoxaemia (3% vs. 6.5%, p = 0.004). Severe hypoxaemia was significantly reduced with capnography only in patients with cardio-respiratory comorbidities (2.2% vs. 4.4%, p = 0.032). The capnography group showed a lower incidence of cardiovascular events. Respiratory adverse events, such as desaturation and airway obstruction, increased with age and ASA classification, as did the need for airway maneuvers. Prolonged apnoea and intubation were rare in both groups. Mandibular traction manoeuvres were significantly more frequent in Group B (9.9% vs. 3%, p < 0.000), reducing the need for other interventions. Patient satisfaction at discharge was higher when capnography was used (p < 0,000). Moderate-deep sedation for GEP performed by experienced anaesthesiologists, combined with capnography, enhances safety, with extremely rare major complications. Capnography monitoring allowed the timely identification and resolution of apnoea and airway obstruction, avoiding severe desaturation and cardiovascular adverse events.

Keywords: Airway obstruction; Apnoea; Capnography; Gastrointestinal endoscopic procedures; Hypoxaemia; Procedural sedation; Respiratory adverse events; Safety.