Does preoperative American Society of Anesthesiologists score relate to complications after total shoulder arthroplasty?

BACKGROUND

For hip and knee arthroplasties, an American Society of Anesthesiologists (ASA) score greater than 2 is associated with an increased risk of medical and surgical complications. No study, to our knowledge, has evaluated this relationship for total shoulder arthroplasty (TSA) or reverse total shoulder arthroplasty (reverse TSA).

QUESTIONS/PURPOSES: We aimed to assess the relationship between the ASA score and (1) surgical complications, (2) medical complications, and (3) hospitalization length after TSA, reverse TSA, and revision arthroplasty.

METHODS

We retrospectively analyzed all patients who had undergone TSAs, reverse TSAs, or revision arthroplasties by the senior author (EGM) from November 1999 through July 2011 who had at least 6 months' followup. Of the 485 procedures, 452 (93.2%) met the inclusion criteria. Data were collected on patient demographics, comorbidities, hospitalization length, and short-term (≤ 6 months) medical and surgical complications. Logistic regression analysis modeled the risk of having postoperative complications develop as a function of the ASA score.

RESULTS

Patients with an ASA score greater than 2 had a greater risk of having a surgical complication develop (p < 0.001; OR, 2.27; 95% CI, 1.36-3.70) and three times the risk of prosthesis failure (ie, component dislocation, component loosening, and hardware failure) (p < 0.001; OR, 3.23; 95% CI, 1.54-6.67). Higher ASA scores were associated with prolonged length of hospitalization (effect size 0.46, p < 0.001), but not medical complications.

CONCLUSIONS

ASA score is associated with surgical, but not medical, complications after TSA and reverse TSA. The ASA score could be used for risk assessment and preoperative counseling.

LEVEL OF EVIDENCE

Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.