Isobaric Spinal Ropivacaine Versus Hyperbaric Spinal Bupivacaine in Total Knee Arthroplasty in Geriatric Patients

Isobaric Ropivacaine 15 mg Versus Hyperbaric Bupivacaine 12.5 mg for Spinal Anesthesia in Geriatric Patients Undergoing Total Knee Arthroplasty

The purpose of this study is to evaluate the efficacy and safety of spinal anesthesia with isobaric ropivacaine, compared with hyperbaric bupivacaine in geriatric patients undergoing lower limb orthopedic surgery.

52 patients physical status II-III according to the American Society of Anesthesiologists classification aged 65 years and above of average height, and scheduled for total knee replacement under spinal anesthesia.

Patients were randomly assigned into two equal groups of 26 patients each according to the type of local anesthetic injected in the subarachnoid space , Group I : patients who received an intrathecal injection of 12.5 mg of 0.5% hyperbaric bupivacaine , Group II: patients who received an intrathecal injection of 15 mg of 0.5% ropivacaine.

The investigators compared both groups as regards the extent and duration of sensory and motor block and hemodynamics including heart rate (HR) , non invasive mean arterial blood pressure (MAP) and respiratory depression.

Inclusion Criteria:

• American Society of Anesthesiologists physical status II-III aged 65 years and above of average height, and scheduled for total knee replacement under spinal anesthesia.

Exclusion Criteria:

• Known hypersensitivity to amide local anesthetics and contraindications to spinal anesthesia.