Spinal Dexamethasone Effect on Cognitive Disorders After Hip Surgery

Proximal femoral fractures (PrFF) are one of the most common causes of emergency admission in the elderly population. The majority of patients have pre-existing conditions that get worsened by unplanned surgery.

Purpose of this article was to evaluate if a is single shot of dexamethasone with levobupivacaine administered intrathecally reduces postoperative pain and cognitive complications in patients with proximal femoral fractures.

The study was performed at a level II trauma center which is a part of a teaching hospital with a catchment population of around 300,000 patients, the first author's affiliation. Around 500 PrFF are performed yearly in the center. All participants gave oral and written informed consent before randomization.

In total, 60 patients with a PrFF, ASA status 2 or 3 were randomized into two groups for spinal anaesthesia as DLSA study group (received 8 mg of dexamethasone and 12.5 mg of 0.5 % levobupivacaine) or LSA control group (received 12.5 mg of 0,5 % levobupivacaine). Postoperative cognitive disturbance was evaluated using simplified Confusion Assessment Method (CAM) scale, pain intensity was measured using Visual Analogue Scale (VAS) and blood samples for defining cortisol concentrations were taken before and after the surgical procedure. The primary outcomes were effects of intrathecal dexamethasone on plasma cortisol affecting cognitive disturbances. Secondary outcomes included pain scores and length of hospital stay. The DLSA group demonstrated a reduced incidence of postoperative cognitive dysfunction (POCD), p=0.043, longer analgesia duration, p<0.001, decreased cortisol levels and shorter hospitalization p=0.045. Intrathecal dexamethasone was the only significant predictor of postoperative delirium, OR 7.76, p=0.019.

Single shot intrathecal administration of dexamethasone with levobupivacaine used in anaesthesia for proximal femoral fractures reduces the stress response by decreasing plasma cortisol concentrations prolonging analgesia. Complications such as delirium and POCD occurred with significantly lower frequency allowing better postoperative rehabilitation and shortening the hospitalization.