The effects of sedation and/or sedation/analgesic drugs administered during central venous catheterization on the level of end-tidal carbon dioxide measured by nasal cannula in our PICU

Abstract

Aim: Sedatives and analgesics are commonly used in pediatric intensive care units during minor invasive procedures. Here, we aimed to measure the changes in end-tidal carbon dioxide (EtCO2) levels with different sedation/analgesic drug administrations (midazolam, ketamine, midazolam + ketamine/fentanyl) during central venous catheterization. Materials and methods: This prospective study included 44 patients who needed sedation/analgesia for central venous catheterization. Patients were sedated with midazolam, ketamine, or midazolam + fentanyl/ketamine. End-tidal carbon dioxide values were measured before and after sedation–analgesia with nasal cannula and recorded from the capnograph. Oxygen saturation (SO2) was monitored by pulse oximetry. Whether respiratory depression occurred during the process was recorded. Results: During the procedure, 15 (34%) patients were given 0.1 mg/kg dose of midazolam described as group I, 18 (41%) patients were given 1 mg/kg dose of ketamine only described as group II, and 11 (25%) patients who could not be effective sedated with a single sedative–analgesic agent were given either 1 mg/kg dose of ketamine or 2 μg/kg dose of fentanyl together with 0.1 mg/kg dose of midazolam described as group III. According to our findings, hypoxia (54.5%) and hypercarbia (45.5%) were detected higher in group III but it was not statistically significant (p = 0.255, p = 0.364). Hypercarbia was detected in 29.5% patients, in 62% of these patients hypercarbia was accompanied by hypoxia, and 38% had only hypercarbia. When presedation and postsedation EtCO2 values were compared, we detected a statistically significant difference in all groups. Conclusion: We detected hypercarbia unaccompanied by hypoxemia in 38% patients. And we think that we have identified these patients early due to measurement of EtCO2 by nasal cannula. This study demonstrated that EtCO2 monitoring via nasal cannula is a feasible and practical way to follow ventilation during sedation/analgesia.