The objective of this study was to compare the block durations and haemodynamic effects associated with intrathecal levobupivacaine or bupivacaine in elderly patients undergoing transurethral prostate surgery. Eighty patients were prospectively randomised to receive plain 1.5 ml levobupivacaine 0.5% (group levobupivacaine) or 1.5 ml plain bupivacaine 0.5% (group bupivacaine) in combination with fentanyl 0.3 ml (15 μg) for spinal anaesthesia. The time to reach T10 and peak sensory block level, and to maximum motor block were significantly shorter in group bupivacaine compared to group levobupivacaine (p < 0.05). Peak sensory block level was also significantly higher in group bupivacaine. In group bupivacaine, mean arterial pressure was significantly lower than group levobupivacaine, starting from 10 min until 30 min after injection (p < 0.05). Hypotension and nausea were less common in group levobupivacaine than group bupivacaine (p < 0.05). Because of the better haemodynamic stability and fewer side-effects associated with levobupivacaine, it may be preferred for spinal anaesthesia in elderly patients.
◊ Reviewed by B. Veering, MD, PhD
Dept of Anesthesiology
Leiden University Medical Center, Leiden, the Netherlands
The decision whether to administer levobupivacaine or bupivacaine for spinal anesthesia should be based on which clinical profile is more favorable for the type of operation. Cardiac toxicity is not clinically relevant at the low doses of bupivacaine that are spinally administered.
Systemic hypotension and bradycardia are the most common cardiovascular disturbances associated with central neural blockade, particularly in the elderly. High levels of sensory anaesthesia and increasing age appear to be the two main risk factors for the development of hypotension after spinal anesthesia. From a clinical point of view, it is important to limit the sympathetic block associated with increased levels of analgesia in older patients after spinal anesthesia.
To control the block height local anesthetics should either be combined with adjuvant drugs resulting in lower doses with fewer side effects or administered at small incremental doses via a continuous spinal technique.
The clinical profile of spinal anesthesia depends on the baricity of the solution. The effect of age on the maximal height of spinal analgesia with isobaric solutions is marginal [1]. With hyperbaric local anesthetic solutions the level of analgesia increases with age [2]. Consequently, levobupivacaine which is an isobaric solution at 37°C [3] is to be preferred over the hyperbaric solution of bupivacaine in elderly patients.
In the present study, low doses of 7.5 mg of levobupivacaine and bupivacaine were used in combination with 15 microg fentanyl. The differences in the clinical profile were marginal and both agents provided a suitable neural blockade. Bupivacaine was associated with only slightly higher incidence of hypotension. Thus, low doses of levobupivacaine and bupivacaine combined with intrathecal fentanyl are both suitable for spinal anesthesia in elderly patients.
◊ References:
[1] Pitkanen M, Haapaniemi L, Tuominen M, Rosenberg PH. Influence of age on spinal anaesthesia with isobaric 0.5% bupivacaine. Br J Anaesth 1984; 56:279-84
[2] Veering BT, Burm AGL, Van Kleef JW, Spierdijk J.
Spinal anesthesia with hyperbaric bupivacaine-effects of age on neural blockade and pharmacokinetics. Br. J. Anaesth. 1988; 60: 187-94.
[3] McLeod GA. Density of spinal anaesthetic solutions of bupivacaine, levobupivacaine, and ropivacaine with and without dextrose. Br J Anaesth. 2004; 92:547-51
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