Ciprofol vs Propofol for Intraoperative Neurophysiological Monitoring in Elderly Patients Undergoing Spinal Surgery: A Randomized Controlled Trial.

Purpose: This study aimed to compare the effects of ciprofol and propofol on motor evoked potentials (MEPs) and somatosensory evoked potentials (SEPs) in elderly patients undergoing spinal surgery. Patients and Methods: This trial enrolled 60 elderly patients scheduled for elective spinal surgery with intraoperative neurophysiological monitoring (IONM) and assigned them to Group C (receiving ciprofol) or Group P (receiving propofol) using random allocation. Primary outcome measures focused on MEPs and SEPs amplitudes of lower extremities at T6. The secondary outcomes encompassed neurophysiological measures (MEPs and SEPs latencies at T6, as well as their amplitudes and latencies at T5), hemodynamic parameters of heart rate (HR), mean arterial pressure (MAP), and bispectral index (BIS) values at T1-T6, along with the incidence of hypotension, bradycardia, requirements for vasoactive medications. Results: Neurophysiological recordings at T6 showed significantly higher amplitudes in Group C across all measured parameters during inter-group comparison. For MEPs, Group C demonstrated greater amplitudes in lower extremities (1378 μV, IQR 1256-1605 vs 1121 μV, IQR 1077-1307; P<0.001). Similarly, SEPs were significantly elevated in Group C for lower extremities (1.34 μV, IQR 0.9-1.63 vs 1.11 μV, IQR 0.82-1.16; P=0.013). However, no inter-group differences existed in MEPs or SEPs latency. From T3 to T6, Group C exhibited higher MAP values than in Group P(all P<0.05); and no intergroup difference in BIS values was observed at T5-T6 (T5: 47.4 ± 4.0 vs 49.1 ± 4.7, P = 0.145; T6: 46.4 ± 3.5 vs 46.2 ± 4.0, P=0.892). Group C had a reduced need for vasoactive medications (13% vs 50%, P = 0.002), less hypotension incidence (17% vs 40%, P= 0.045). Conclusion: Ciprofol outperforms propofol in hemodynamic stability for the elderly undergoing spinal surgery, with less suppression of the amplitudes of MEPs and SEPs, and no prolongation of latency, thereby potentially improving the quality of IONM. Trial Registration Clinicaltrialsgov Identifier: ChiCTR2400091429.