Postoperative delirium after major orthopedic surgery

Area of Science:

• Geriatric Anesthesiology
• Surgical Outcomes Research
• Postoperative Complication Surveillance

Background:

• Postoperative delirium (POD) is a frequent complication in elderly patients after elective surgery.
• Limited institutional data exists comparing surgical types, anesthesia, and analgesia in relation to POD incidence.

Purpose of the Study:

• To determine the incidence of POD after non-ambulatory orthopedic surgery.
• To assess if surgical procedure type influences POD incidence.
• To identify modifiable risk factors for POD in this patient population.

Main Methods:

• Retrospective cohort study of 78,492 non-ambulatory orthopedic surgeries (2009-2014).
• Exclusion of patients under 18; data extracted from electronic medical records.
• POD identification using ICD-9 codes not present on admission; analysis by surgical procedure type.

Main Results:

• Overall POD incidence was 1.2%; higher in spine fusions (3.3%) and fracture repairs (7.2%) compared to total hip arthroplasty (0.8%).
• Advanced age, ASA score ≥3, comorbidities, hyponatremia, parenteral diazepam, and alcohol dependence were significant risk factors.
• Intravenous patient-controlled analgesia was a risk factor for THA; general anesthesia was not a significant factor.

Conclusions:

• The observed POD incidence of 1.2% is lower than previously reported, potentially due to multimodal regional anesthesia and early ambulation.
• Both non-modifiable (e.g., age) and modifiable (e.g., medication, alcohol use) factors contribute to POD risk.