[Influence of the fascia iliaca compartment block on postoperative cognitive status in the elderly]

Abstract

Objective: The aim of this study was to assess the influence of a regional analgesia technique on the incidence of postoperative cognitive dysfunction (POCD) after hip surgery, in elderly patients.

Patients and methods: Patients, aged over 65 years, were assigned in two groups according to the anaesthesia technique: group NKT (general anaesthesia with target concentration infusion of propofol and remifentanil, with a 0.1 mg/kg-bolus of morphine at the end of surgery), group KT (preoperative iliaca compartment block with catheter and then general anaesthesia without bolus of morphine). Postoperative analgesia was similar in both groups: paracetamol, tramadol, and subcutaneous morphine if verbal pain scale equal or greater than 2 (0.1 mg/kg). POCD was defined as a decrease in Mini Mental Status (MMSE) equal or greater than 2 points and was monitored during 2 days. Consumption of opioids, pain scores and side effects were recorded.

Results: Sixty-five patients were included: 34 in NKT group and 31 in KT group. MMSE scores were higher in the KT group at day 1 and day 2 (p=0.01 and 0.0004, respectively). POCD was less frequent in group KT at day 2 (6 % vs 41 % ; p=0.001) and pain scores were lower during the first 48 hours (p=0.03). Remifentanil consumption was lower in KT group (0.43+/-0.18 mg vs 0.61+/-0.25 mg, p=0.002). Total amount of morphine, including the bolus in NKT group, was significantly lower in KT group (7 [5-17] mg vs 0 [0-5] mg, p<10(-6)).

Conclusion: Postoperative analgesia by iliaca compartment block with catheter seems to provide a decrease in the incidence of POCD after hip surgery in elderly patients.

Study design: Prospective, observational study.