A Comparative Study Between Bupivacaine And Clonidine Associated With Bupivacaine In Cervical Plexus Block For Carotid Endarterectomy

Clonidine as an adjuvant to ropivacaine-induced supraclavicular brachial plexus block for upper limb surgeries

Background and Aims:

Ropivacaine is a new amide, long acting, pure S-enantiomer, local anesthetic, with differential blocking effect. The addition of clonidine to local anesthetic improves the quality of peripheral nerve blocks. This study was conducted to evaluate the effect of clonidine on characteristics of ropivacaine-induced supraclavicular brachial plexus block.

Material and Methods:

A total of 60 adult patients were randomly recruited to two groups of 30 each: Group I: 30 ml 0.75% ropivacaine + 1 ml normal saline. Group II: 30 ml 0.75% ropivacaine + 1 mcg/kg clonidine diluted to 1 ml with normal saline.

Results:

The onset of sensorimotor block was earlier in Group II (4.36 ± 0.81 min for sensory block and 9.83 ± 1.12 min for motor block) than in Group I (4.84 ± 0.65 min for sensory block and 10.85 ± 0.79 min for motor block). The duration of both sensory and motor block were significantly prolonged by clonidine (P < 0.001). The duration of analgesia was also prolonged in patients receiving clonidine (613.10 ± 51.797 min vs. 878.33 ± 89.955 min). Although incidence of hypotension and bradycardia was higher in Group II when compared to Group I, it was not clinically significant.

Conclusions:

Ropivacaine 0.75% is well-tolerated and provides effective surgical anesthesia as well as relief of postoperative pain. Clonidine as an adjuvant to ropivacaine significantly enhances the quality of supraclavicular brachial plexus block by faster onset, prolonged duration of sensory and motor block and improved postoperative analgesia, without associated adverse effects at the dose used.

Association of clonidine and ropivacaine in brachial plexus block for shoulder arthroscopy

BACKGROUND AND OBJECTIVES

Arthroscopy for shoulder disorders is associated with severe and difficult to control pain, postoperatively. The addition of clonidine to local anesthetics for peripheral nerve block has become increasingly common, thanks to the potential ability of this drug to reduce the mass of local anesthetic required and to prolonging analgesia postoperatively. The present study aimed to evaluate the success of brachial plexus block for arthroscopic rotator cuff surgery using local anesthetic with or without clonidine.

METHOD

53 patients of both genders, between 18 and 70 years old, American Society of Anesthesiologists I or II, who were scheduled to undergo arthroscopic shoulder surgery were selected. Patients were then randomized into two groups. The verbal numerical pain scale and the presence of motor block were obtained in the post-anesthetic recovery room and 6, 12, 18 and 24h postoperatively.

RESULTS

The association of clonidine (0.15mg) to a solution of 0.33% ropivacaine (30mL) in brachial plexus block for shoulder arthroscopy has not diminished the visual numeric pain scale values, nor the need for opioid rescue postoperatively. There was a lower incidence of nausea/vomiting postoperatively and a significant motor block time prolongation in the group of patients who received clonidine as adjuvant.

CONCLUSIONS

The use of brachial plexus block with local anesthetic for analgesic postoperative control is well established in the literature. The addition of clonidine in the dose proposed for prolongation of the analgesic effect and reduction of opioid rescue proved unhelpful.

A randomized controlled double-blinded prospective study of the efficacy of clonidine added to bupivacaine as compared with bupivacaine alone used in supraclavicular brachial plexus block for upper limb surgeries

We compared the effects of clonidine added to bupivacaine with bupivacaine alone on supraclavicular brachial plexus block and observed the side-effects of both the groups. In this prospective, randomized, double-blinded, controlled trial, two groups of 25 patients each were investigated using (i) 40 ml of bupivacaine 0.25% plus 0.150 mg of clonidine and (ii) 40 ml of bupivacaine 0.25% plus 1 ml of NaCl 0.9, respectively. The onset of motor and sensory block and duration of sensory block were recorded along with monitoring of heart rate, non-invasive blood pressure, oxygen saturation and sedation. It was observed that addition of clonidine to bupivacaine resulted in faster onset of sensory block, longer duration of analgesia (as assessed by visual analogue score), prolongation of the motor block (as assessed by modified Lovett Rating Scale), prolongation of the duration of recovery of sensation and no association with any haemodynamic changes (heart rate and blood pressure), sedation or any other adverse effects. These findings suggest that clonidine added to bupivacaine is an attractive option for improving the quality and duration of supraclavicular brachial plexus block in upper limb surgeries.