Low dose hyperbaric bupivicaine injected at T12–L1 provides adequate anesthesia with stable hemodynamics for elderly patients undergoing TURP

摘要

Background Elderly patients undergoing transurethral resection of the prostate (TURP) may have preexisting cardiac or cerebral dysfunction. Maintaining hemodynamic stability is essential. The objective of this study was to compare the anesthetic efficacy and cardiovascular stability of a subarachnoid injection of 7.5 mg hyperbaric bupivacaine at the level of T12–L1 to 15 mg hyperbaric bupivacaine injected at the level of L3–4 for elderly patients undergoing TURP. Methods Fifty patients undergoing TURP were enrolled. Patients were randomized to either of two groups: Group I: Dural puncture was performed in the midline at the T12–L1 interspace. 7.5 mg of hyperbaric bupivacaine (1.5 ml of 0.5% solution) was then injected through a 16 gauge/26 gauge combined spinal–epidural by “needle through needle” technique. Group II: Dural puncture was performed in the midline at the L3–4 interspace. Fifteen milligrams of hyperbaric bupivacaine (3 ml of 0.5% solution) was then injected through a 25-gauge spinal needle. Demographic data, prostate size, volume of irrigation fluids, hemodynamic parameters, block characteristics, and complications were recorded. Results Demographic data, prostate size, volume of irrigating fluids, complications and duration of surgery were comparable in both groups. Patients in Group I exhibited a more stable blood pressure and heart rate during the study time period ( P 0.05). The duration of sensory and motor blockade were shorter in Group I ( P 0.05). Patients in Group II demonstrated a significantly higher peak sensory block (T4, P 0.05), shorter mean time to peak sensory block (4.8 ± 1.1 min, P 0.05), and earlier onset of sensory block at T10 (2.6 ± 0.5 min, P 0.05). Conclusion Injection of 7.5 mg hyperbaric bupivacaine at the level of T12–L1 is sufficient to provide adequate sensory block while maintaining hemodynamic stability for TURP. This dose and injection location may offer an additional advantage of decreased duration of motor block in patients undergoing TURP.