Use of Digital Pupillometry to Measure Sedative Response to Propofol

Digital pupillometry (DP) accurately and precisely measures pupillary responses. Little is known about using DP to measure the sedative effect of isolated propofol administration. We conducted a cross-sectional study of 19 adults undergoing moderate sedation with propofol during which we measured pupillary changes using DP. Maximum and minimum pupillary diameters decreased significantly with propofol (mean change from baseline to procedural termination -1.24 mm, standard error [SE] 0.25 and -0.79 mm, SE 0.13, respectively; ≤0.001 for both). Mean constriction velocity decreased by 0.84 mm/s between baseline and procedural termination 0.001). Pupillary latency increased significantly between baseline and induction (mean change 0.016 seconds, SE 0.007; =0.04) but was not significantly different at other time points. We speculate that DP may be a useful tool to monitor propofol sedation.