Effects of remimazolam vs. propofol on plasma neurofilament light chain and postoperative delirium in frail elderly patients undergoing major non-cardiac surgery: a prospective, randomized, assessor-blinded controlled trial.
In frail elderly patients undergoing major non-cardiac surgery, remimazolam does not show significant advantages over propofol in reducing plasma neurofilament levels or postoperative delirium incidence, though it may offer better hemodynamic stability.
Where it sits
this study against the rest of the zenagamtide corpusSummary and findings
This study measured plasma neurofilament light chain (NfL) concentrations and the incidence of postoperative delirium (POD) in frail elderly patients undergoing major non-cardiac surgery. Patients received either remimazolam or propofol for anesthesia. No significant differences were found between the two groups regarding NfL levels or POD incidence.
Abstract
<h4>Background</h4>The relationship between remimazolam administration and early neurological complications, particularly postoperative delirium (POD), in elderly patients undergoing major non-cardiac surgery remains unclear. Plasma neurofilament light chain (NfL) is a potential biomarker for central nervous injury. This study aims to compare the effects of remimazolam and propofol on postoperative plasma NfL concentrations and the incidence of POD in frail elderly patients undergoing major non-cardiac surgery.<h4>Methods</h4>This was a single-center randomized controlled trial on frail patients who underwent non-cardiac surgery. Participants were randomized to receive either Remimazolam (Group R) or Propofol (Group P) for induction and maintenance of general anesthesia, with all other anesthetic management standardized. The primary outcome was plasma NfL concentration on postoperative day 1, and the incidence of POD was assessed as a key clinical secondary endpoint. The secondary endpoint encompassed the incidence of hypotension during the anesthesia induction, as well as the time-weighted average of the area under the curve below the baseline for mean arterial pressure (AUB-MAP).<h4>Results</h4>A total of 123 patients were enrolled. No significant differences were observed in plasma NfL concentrations on postoperative day 1 between Group R and Group P (123.3[83.6-198.2] vs. 149.0[102.0-226.6], pg/ml, P = 0.186, respectively); and similarly, no differences in POD were found between Group R and Group P (6/62[9.7%] vs. 7/61[11.5%], unadjusted odds ratio 0.827, 95% CI 0.261-2.62, P = 0.746). In the secondary outcomes, the incidence of hypotension during the anesthesia induction in Group R was significantly decreased (3[4.8%] vs. 19[31.3%], P < 0.001). And the time-weighted average of AUB-MAP in Group R was higher than Group P (-21.3 ± 10.7 vs. -25.4 ± 9.6, mmHg, P = 0.03).<h4>Conclusions</h4>In frail elderly patients undergoing major non-cardiac surgery, remimazolam group shows no significant difference from propofol in plasma NfL levels or POD incidence on the first day. Due to its advantage in maintaining hemodynamic stability, remimazolam may be a safer anesthetic option for frail patients sensitive to hemodynamic changes.<h4>Trial registration</h4>Chinese Clinical Trials Registry, ChiCTR2400093862.
Background
The study investigates the effects of remimazolam compared to propofol on postoperative outcomes in frail elderly patients, specifically focusing on plasma neurofilament light chain (NfL) as a biomarker for neurological injury and the incidence of postoperative delirium (POD). Previous research has indicated potential neurological risks associated with anesthesia in this population, but the specific impact of remimazolam remains unclear. This study aims to clarify these effects, which could influence anesthetic choices in vulnerable patients.
Methods
This was a single-center randomized controlled trial involving frail patients undergoing major non-cardiac surgery. A total of 123 patients were randomized to receive either remimazolam (Group R) or propofol (Group P) for induction and maintenance of anesthesia. The primary outcome was plasma NfL concentration measured on postoperative day 1, while secondary outcomes included the incidence of POD and hypotension during anesthesia induction.
Results
No significant differences were observed in plasma NfL concentrations between the two groups on postoperative day 1, with values of 123.3[83.6-198.2] pg/ml for Group R and 149.0[102.0-226.6] pg/ml for Group P (P=0.186). The incidence of POD was also similar, with 6/62[9.7%] in Group R and 7/61[11.5%] in Group P (P=0.746). However, hypotension during anesthesia induction was significantly less frequent in Group R (3[4.8%]) compared to Group P (19[31.3%], P<0.001). Additionally, the time-weighted average of AUB-MAP was higher in Group R (-21.3 ± 10.7 mmHg) compared to Group P (-25.4 ± 9.6 mmHg, P=0.03).
Interpretation
The findings indicate that remimazolam does not significantly reduce plasma NfL levels or the incidence of POD compared to propofol in frail elderly patients. While the statistical significance of hypotension and AUB-MAP suggests potential hemodynamic benefits of remimazolam, the clinical relevance of these findings may be limited by the small effect sizes and the absence of significant differences in primary outcomes. The single-center design and the specific population studied may also restrict the applicability of these results to broader clinical practice.
Key findings
- Plasma NfL concentrations on postoperative day 1 were 123.3[83.6-198.2] pg/ml for Group R and 149.0[102.0-226.6] pg/ml for Group P, P=0.186.
- The incidence of POD was 6/62[9.7%] in Group R and 7/61[11.5%] in Group P, P=0.746.
- The incidence of hypotension during anesthesia induction was 3[4.8%] in Group R vs. 19[31.3%] in Group P, P<0.001.
- The time-weighted average of AUB-MAP was -21.3 ± 10.7 mmHg for Group R and -25.4 ± 9.6 mmHg for Group P, P=0.03.
Limitations
- Single-center study may limit generalizability.
- Sample size of 123 may not provide sufficient power for all outcomes.
- No long-term follow-up reported.