Comparison of unilateral spinal and continous spinal anesthesia for hip surgery in elderly patients.

BACKGROUND: Continous spinal anesthesia (CSA) and frequently unilateral spinal anesthesia (USpA) are usually preferred for lower extremity surgeries. In this study, we aimed to compare the effects of these anesthetic techniques, on hemodynamic parameters, quality of anesthesia and complications in elderly patients undergoing hip surgeries. METHODS: Forty patients aged 65 years and older, assigned to receive either CSA or USpA with 7.5 mg (1.5 cc) 0.5% hyperbaric bupivacaine initially. In CSA group, additional doses of 2.5 mg bupivacaine were applied until sensory block reach to T10. Maximum sensorial block level, time to reach the level of T10 (defined as onset time) and to regress to T12, hemodynamic parameters and ephedrine requirements were recorded peroperatively and during 2 h postoperatively. RESULTS: Hemodynamic parameters, ephedrine requirements and regression of sensory block by two levels were similar in two groups. The onset time of anesthesia was significantly longer in USpA group than CSA group. Neuraxial anesthesia had to be converted to general anesthesia in 5 patients (25%) in CSA group and 1 patient (5%) in USpA group. CONCLUSIONS: We conclude that both USpA and CSA techniques have similar effects in elderly high risk patients. On the other hand, USpA is more preferable for surgeries with shorter durations due to its low cost and high success rate.

Comparison of buccal and nasal dexmedetomidine premedication for pediatric patients.

BACKGROUND: Alpha-2 adrenergic agonists are used to premedicate pediatric patients to reduce separation anxiety and achieve calm induction. The clinical effects of clonidine are similar whether via the oral or nasal route. However, oral dexmedetomidine is not preferred because of its poor bioavailability. The objective of this study was to evaluate the effects of nasal versus buccal dexmedetomidine used for premedication in children. METHODS: Sixty-two patients, aged 2-6 years, undergoing minor elective surgery were randomly assigned to two groups to receive dexmedetomidine, either 1 µg·kg(-1) buccally (group B) or 1 µg·kg(-1) intranasally (group N) for premedication 45 min before the induction of anesthesia. Heart rate, peripheral oxygen saturation, and respiratory rate were measured before and every 10 min after administering dexmedetomidine in all children. Level of sedation was assessed every 10 min until transport to operating room. Drug acceptance, parental separation, and face mask acceptance scores were recorded. RESULTS: There was no significant difference between the two groups in patient characteristics, nor was there any significant difference between the two groups in heart rate, respiratory rate, or SpO(2) values at all times after premedication. Levels of sedation, parental separation, and mask acceptance scores were significantly higher in group N than in group B at the various times. CONCLUSIONS: These results suggest that intranasal administration of 1 µg·kg(-1) dexmedetomidine is more effective than buccal administration of 1 µg·kg(-1) dexmedetomidine for premedication in children.

The effects of Different Concentrations and Equivalent Volumes of Levobupivacaine in Epidural Anesthesia.

BACKGROUND: Levobupivacaine, the S(-) isomer of bupivacaine, is less cardiotoxic than racemic bupivacaine. Previous studies have examined different concentrations of levobupivacaine in similar ways. OBJECTIVES: This prospective, randomized, double-blind study was designed to determine the clinical efficacy and hemodynamic effects of different concentrations and equivalent volumes of levobupivacaine in epidural anesthesia. To our knowledge, this is the first study to evaluate the effects of concentration lower than 0.5% levobupivacaine. METHODS: Forty adult patients with an American Society of Anesthesiology (ASA) I-III physical status undergoing transurethral endoscopic surgery were randomly divided into 2 groups to receive either 10 mL of isobaric levobupivacaine (0.5% + 5 mL 0.9% saline [group 1; n = 20]) or 10 mL of isobaric levobupivacaine (0.75% + 5 mL saline 0.9% saline [group 2; n = 20]) for epidural anesthesia. An observer blinded to group division evaluated the time of onset, maximum level, and time to 2-segment regression of sensory block. RESULTS: There were no differences between the 2 groups in terms of hemodynamic parameters and time of onset of the sensory block. There were significant differences, however, between the 2 groups in the maximum level of the sensory block (group 1, T9; group 2, T8; P = 0.010) and the time to 2-segment regression of sensory block (group 1, 46.35 minutes; group 2, 62.94 minutes; P = 0.013). CONCLUSION: This study indicated that 10 mL of 0.5% levobupivacaine plus 5 mL of 0.9% saline is a suitable solution for use in epidural anesthesia because it produces a block clinically comparable to that of 10 mL of 0.75% levobupivacaine plus 5 mL of 0.9% saline for transurethral resection of prostate surgery.