Application for ESRA Abstract Prizes: I apply as an Anesthesiologist (Aged 35 years old or less)

Background and Aims Spinal anesthesia (SA) is considered contraindicated in patients with aortic stenosis (AS), due to the sympathetic block, decrease in peripheral vascular resistance, hypotension, decrease in coronary perfusion, and potential for acute myocardial ischemia. However, low-dose isobaric bupivacaine (ISOBUPI) is often used in clinical practice with little hemodynamic consequences. This study evaluates the use of SA with ISOBUPI in AS patients receiving lower limb surgery.

Methods Medical records of patients with moderate to severe AS having lower limb orthopedic surgery and receiving SA (≤ 10 mg ISOBUPI 0.5%) were screened for the occurrence of hypotension, intraoperative vasopressor therapy, and 24-hour and 30-day mortality. Hypotension was defined as a systolic blood pressure (SBP) < 80 mmHg or mean arterial pressure (MAP) < 65 mmHg.

Results Thirty-five patients with moderate (n=16) to severe AS (n=19) receiving SA for lower extremity surgery were included. No 24-hour or 30-day mortality was observed. Hypotension with SBP < 80 mmHg occurred in 20% of the patients, and 51% had a MAP < 65 mmHg. Hypotensive events were treated with norepinephrine 0.04 mcg/kg/min (IQR: 0.04 – 0.04) or ephedrine 10 mg (IQR: 10 – 20), phenylephrine 200 mcg (125 – 275). No severe hemodynamic instability or other vasoactive interventions were observed.

Conclusions Spinal anesthesia in patients with AS did not result in refractory hypotension or adverse outcomes. These data suggest that AS should not constitute an absolute contraindication and that studies are needed to formally evaluate the utility and safety of low-dose SA with ISOBUPI in patients with AS.