Protecting Respiration During Conscious Sedation Using Inspired Carbon Dioxide: A Simulation Study

Salt Lake Community College

Conscious sedation procedures require sedation and analgesia sufficient for the particular procedure but not so deep as to cause apnea. Fast acting sedatives such as Propofol are increasingly used in these procedures although they cause more severe respiratory depression than more traditional sedatives such as Midazolam. A method was devised to maintain respiration during conscious sedation by administering inspired CO₂ as a respiratory stimulant to offset the reduced respiratory drive caused by Propofol. A computer model was implemented which predicts respiratory depression caused by Propofol administration. Simulations of common dosing regimens were performed with and without inspired CO₂. For all dosing regimens, adding inspired CO₂ prevented the respiration from falling as much as the control and respiration returned to baseline within 4 to 6 minutes. Administering inspired CO₂ during conscious sedation seems to be an effective way to prevent respiratory depression according to the best available numerical model.