Comparison of general anesthesia and spinal anesthesia in patients with moderate to severe aortic stenosis undergoing surgery for hip fracture: a retrospective cohort study

Patients with moderate to severe aortic stenosis undergoing hip fracture surgery are at high risk for perioperative complications, but data comparing spinal anesthesia and general anesthesia are limited. Historically, spinal anesthesia has been considered relatively contraindicated in patients with aortic stenosis, but there is no clear evidence supporting this assumption. We conducted a single-center retrospective observational study of patients with moderate to severe aortic stenosis undergoing hip fracture surgery. Patients were classified by anesthetic technique (general anesthesia or spinal anesthesia). The primary outcome was intraoperative hypotension, quantified as the area under the threshold, representing the duration and magnitude of mean arterial pressure below 65 mmHg. Secondary outcomes included the ratio of hypotensive time to total anesthesia time, vasopressor requirements, 30-day mortality, postoperative complications, time to first analgesic request, and numeric rating scale pain scores postoperatively. Among 103 patients analyzed (general anesthesia = 76; spinal anesthesia = 27), baseline characteristics were comparable between groups. Spinal anesthesia was associated with lower area under the threshold for mean arterial pressure below 65 mmHg (β = -390 mmHg·min, 95% CI, -760 to -24; p = 0.04) and reduced phenylephrine use (β = -1.6 mg, 95% CI, -2.7 to -0.45; p < 0.01). There were no statistical differences between groups in mortality and postoperative complications (30-day mortality: OR 0.60, 95% CI, 0.03 to 11; p = 0.72; AKI: OR 0.81, 95% CI, 0.27 to 2.5; p = 0.71; delirium: OR 0.52, 95% CI, 0.19 to 1.4; p = 0.21; heart failure: OR 1.4, 95% CI, 0.41 to 5.1; p = 0.57). In patients with moderate to severe aortic stenosis undergoing hip fracture surgery, spinal anesthesia was associated with reduced intraoperative hypotension and vasopressor use compared with general anesthesia. These results suggest that spinal anesthesia may be a feasible alternative to general anesthesia in this patient population, though prospective confirmation is needed.