152 Using Near-Infrared Spectroscopy for Tissue Oxygenation Monitoring During Procedural Sedation: the Association of StO2 Changes With Supportive Airway Measures

Abstract

Study Objectives: To assess if changes in StO2 detect patients who required supportive airway measures during procedural sedation.Methods: This was observational study of adult patients undergoing procedural sedation in the emergency department (ED). Patients underwent procedural sedation with either propofol 1 mg/kg followed, ketamine 0.5 mg/kg combined with propfol 0.5 mg/kg (1:1), or propofol 0.8 mg/kg combined with ketamine 0.2 mg/kg (4:1) in an IV bolus, followed by ½ of the initial dose every 3 minutes as needed for deep procedural sedation. Doses, vital signs, end-tidal CO2 (EtCO2), pulse oximetry, and StO2 were recorded. Supportive airway measures used during the procedure (bag-valve mask use, airway repositioning, increased supplemental oxygen, or stimulation to induce respiration) were recorded. The percent change in StO2 between baseline and nadir was compared between patients who required a supportive airway measures and those who did not using Wilcoxon rank sum tests.Results: Fifty patients were enrolled, 17 sedated with propofol, 16 sedated with 1:1 propofol/ketamine and 17 sedated with 4:1 propofol/ketamine. No significant adverse events were noted. The median total dose of propofol was 0.15 mg/kg (range 0.09 to 2.5) for the propofol group, 0.05 mg/kg (range 0.04 to 0.15) for the 1:1 group, and 0.13 mg/kg (range 0.05 to 0.26) for 4:1 and of ketamine was 0.05 mg/kg (range 0.04 to 0.15) for the 1:1 group, and 0.03 mg/kg (range 0.01 to 0.07) for 4:1. The median time of the procedure was 15 minutes (range 10 to 27). supportive airway measures were noted in 25/50 (50%). The mean change in StO2 from baseline to nadir in patients that required a supportive airway measures was 27.8% (95% CI=10.7% to 44.8%) and in patients that did not require a supportive airway measures was 11.4% (95% CI=4.9% to 18.0%) (p=0.04).Conclusions: StO2 changes from baseline were larger in patients who required supportive airway maneuvers during procedural sedation. Tissue perfusion monitoring may be a useful detector of respiratory depression and the need for intervention in patients undergoing procedural sedation in the ED. Study Objectives: To assess if changes in StO2 detect patients who required supportive airway measures during procedural sedation. Methods: This was observational study of adult patients undergoing procedural sedation in the emergency department (ED). Patients underwent procedural sedation with either propofol 1 mg/kg followed, ketamine 0.5 mg/kg combined with propfol 0.5 mg/kg (1:1), or propofol 0.8 mg/kg combined with ketamine 0.2 mg/kg (4:1) in an IV bolus, followed by ½ of the initial dose every 3 minutes as needed for deep procedural sedation. Doses, vital signs, end-tidal CO2 (EtCO2), pulse oximetry, and StO2 were recorded. Supportive airway measures used during the procedure (bag-valve mask use, airway repositioning, increased supplemental oxygen, or stimulation to induce respiration) were recorded. The percent change in StO2 between baseline and nadir was compared between patients who required a supportive airway measures and those who did not using Wilcoxon rank sum tests. Results: Fifty patients were enrolled, 17 sedated with propofol, 16 sedated with 1:1 propofol/ketamine and 17 sedated with 4:1 propofol/ketamine. No significant adverse events were noted. The median total dose of propofol was 0.15 mg/kg (range 0.09 to 2.5) for the propofol group, 0.05 mg/kg (range 0.04 to 0.15) for the 1:1 group, and 0.13 mg/kg (range 0.05 to 0.26) for 4:1 and of ketamine was 0.05 mg/kg (range 0.04 to 0.15) for the 1:1 group, and 0.03 mg/kg (range 0.01 to 0.07) for 4:1. The median time of the procedure was 15 minutes (range 10 to 27). supportive airway measures were noted in 25/50 (50%). The mean change in StO2 from baseline to nadir in patients that required a supportive airway measures was 27.8% (95% CI=10.7% to 44.8%) and in patients that did not require a supportive airway measures was 11.4% (95% CI=4.9% to 18.0%) (p=0.04). Conclusions: StO2 changes from baseline were larger in patients who required supportive airway maneuvers during procedural sedation. Tissue perfusion monitoring may be a useful detector of respiratory depression and the need for intervention in patients undergoing procedural sedation in the ED.