Are Patient-reported Drug Allergies Associated with Perioperative Complications Following Correction of Cervical Deformity?

Introduction: Prior studies have demonstrated a correlation between drug allergies and postoperative complications in joint arthroplasty. This has not been studied in the context of cervical deformity (CD).

Methods: Patients >18 years were included. Drug allergies were recorded if patients reported allergic symptoms (e.g., rash, anaphylaxis, etc) upon administration of the medication. Outcomes: perioperative complications, including pulmonary embolism, deep vein thrombosis, urinary tract infection, urinary retention, pneumonia, compromising neurological deficit (paralysis, immobility), dysphagia, dysphonia, surgical site infection (superficial or deep), and readmission. Student’s t-tests, binary and multivariable logistic regression analyses were used to evaluate the effect of type of drug allergy and incidence of various complications.

Results: 219 patients included. Mean age was 55.7 ± 8.9 years, 46% were female, mean BMI was 29.8 ± 6.4 kg/m2, mean levels fused was 4.6 ± 2.1, mean EBL was 583 ± 686 mL, mean operative time was 338 ± 144 min, and mean LOS was 5.1 ± 6.8 days. 26.3% of patients underwent an anterior approach, 35.4% underwent a posterior approach, and 36.4% underwent a combined (i.e., anterior and posterior) approach. 38% of patients reported at least one drug allergy (mean 0.9±1.3). Patients who reported any drug allergy were more likely to be female (69% vs. 32%, p<.001). Within 90 days of surgery, 17.7% of patients suffered at least one complication. Patients with any reported drug allergies had higher rates of perioperative complications (24.4% vs. 13.5%, p=.043), particularly with respect to rates of SSI (7.9% vs. 1.5%, p=.022). Increasing number of drug allergies did not increase the likelihood of developing complications (p>.5). Controlling for age, BMI, surgical approach, and number of levels fused, adjusted analysis revealed patients with any reported allergies were more likely to suffer any type of complication (OR: 3.0, [1.4-6.8]; p=.007), specifically SSI (OR: 10.9, [1.2-97.6]; p=.032).

Conclusion : Cervical deformity patients who report drug allergies may be at increased risk for perioperative complications, especially surgical site infections. To our knowledge, this is a novel concept with respect to cervical spine surgery.