The effects of clonidine on postoperative analgesia after peripheral nerve blockade in children.
BACKGROUND
The effect of clonidine on the duration of sensory blockade after peripheral nerve blockade is controversial. We evaluated the effects of clonidine on the duration of sensory and motor block and analgesia time in children who underwent a variety of peripheral nerve blocks.


METHODS
We reviewed the regional anesthesia database that contains data on children who underwent an infraclavicular, lumbar plexus, femoral, fascia iliaca or sciatic nerve block for postoperative analgesia at The Children's Hospital of Philadelphia between October 2002 and December 2005. Patients were prospectively followed after the nerve block.


RESULTS
Two hundred fifteen patients (47%) received either bupivacaine or ropivacaine local anesthetic (LA) and 220 (53%) a combination of local anesthetic and clonidine (LAC). The duration of sensory block was significantly longer in the LAC (17.2 +/- 5 h) compared with that in the LA group (13.2 +/- 5 h) (P = 0.0001). The increase in duration was independent from the type of peripheral nerve block, local anesthetic used and operation performed. The motor block duration was significantly longer in the LAC group (9.6 +/- 5 vs 4.3 +/- 4 h, P = 0.014). Two patients in the LAC and one in the LA group experience prolonged numbness (max 72 h). No paresthesia or dysesthesia was observed.


CONCLUSIONS
The addition of clonidine to bupivacaine and ropivacaine can extend sensory block by a few hours, and increase the incidence of motor blocks.
Cucchiaro
Giovanni
G
Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. cucchiaro@email.chop.edu
Ganesh
Arjunan
A
D000293:Adolescent; D000328:Adult; D000577:Amides / Q000008:administration & dosage; D000700:Analgesics / Q000008:administration & dosage*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003000:Clonidine / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D009407:Nerve Block / Q000379:methods*; D010525:Peripheral Nerves / Q000473:pathology*; D011446:Prospective Studies; D000077212:Ropivacaine; D013997:Time Factors
D000577:Amides; D000700:Analgesics; D000779:Anesthetics, Local; D000077212:Ropivacaine; D003000:Clonidine; D002045:Bupivacaine