Factors of presenting an acute confusional syndrome after a hip fracture.

Introduction: Acute confusional syndrome (ACS) is a geriatric syndrome that manifests itself with changes in cognition, attention, underactive or hyperactive motor response, and fluctuation in the level of consciousness after trauma, hospitalisation or surgery. The objective is to know the risk factors and prevention of acute confusional syndrome in the elderly with hip fractures (HF) .

Methods: Prospective observational cohort study. The inclusion criteria was to be age ≥ 65 and HF operated under selective spinal anesthetic (bupivacaine ≤ 7 mg + fentanyl 10-15 .mu.g) without benzodiazepine, ketamine or propofol. The potential risk factors of ACS were recorded: demographic variables, fracture type, Charlson index, ASA risk, performance of a peripheral nerve block (PNB), and scale scores: Barthel, Fried, Pfeifer, RCMS, MNA and VAS. ACS was diagnosed by the CAM questionnaire. The risk factors were estimated by binary logistic regression.

Results: Of the 133 patients included, 60 (45.11%) developed preoperative ACS, and 25 developed (18.8%) postoperative ACS. Having identified cognitive impairment with ≥ 3 points on the RCMS (OR 11.04 [ 95% ic: 1.3 - 89.1], p <0.001) or Pfeiffer (OR 6.94 [95% ic: 1.07 - 44.69], p <0.0 41) was a risk factor of ACS. Among patients with cognitive impairment or dementia, the increase of surgical delay (OR 1.95 [ 95% CI: 1.2 -2.91], p <0.001) was associated with the increased likelihood of presenting perioperative ACS, while performing a perioperative PNB decreased the likelihood of presenting perioperative ACS (without PNB: 43.8%, with PNB: 4.7%, OR 0.3 [0.2 to 0.43], p <0.001).

Conclusion: Identifying patients with HF and cognitive impairment using RCMS or the Pfeiffer test and performing HF surgery within 36 h administering perioperative PNB could reduce the incidence of ACS.