Spinal anesthesia with bupivacaine and fentanyl in geriatric patients

We assessed the risks and benefits of the administration of fentanyl during spinal anesthesia in the elderly. Forty patients (70-83 yr) undergoing knee or hip replacement were studied. Preoperatively, cognitive function (minimental state examination [MMSE]), associated pathology, medications, and treatment were evaluated. Patients had spinal anesthesia with 12.5 mg bupivacaine plus saline (SS; n = 21) or 25 micrograms fentanyl (FN; n = 19). The number of ailments and drugs per patient were 2.5 and 2.3, respectively; 35%-44% of disorders were untreated, 16%-26% were symptomatic, and 33% were adequately treated. Groups were comparable regarding demographic data and characteristics of the spinal block. Group FN had more pruritus (P < 0.02) and lower SaO2 (P < 0.007), but prevalence of side effects was similar. Pain intensity (visual analog scale [VAS], facial expression test [FET] at the time of analgesia request (TAR) was lower in Group FN (P < 0.01). A poor correlation between VAS and FET (range 0.42-0.58) was obtained. MMSE at hospital discharge was no different from preoperative values. Our results show that 25 micrograms of spinal fentanyl do not modify spinal anesthesia in the elderly, but induces pruritus and O2 desaturation. The decrease in postoperative pain intensity and the preservation of cognitive function would justify the use of spinal fentanyl in the elderly.