Bayesian enhanced meta-analysis of post-operative analgesic efficacy of additives for caudal analgesia in children.
BACKGROUND
The authors calculated the effect size for post-operative analgesia of three additives, clonidine, neostigmine, and tramadol to bupivacaine, ropivacaine, or levobupivacaine used for single-dose caudal extradural blockade in children.


METHODS
A meta-analysis was performed for three end points of efficacy: the increase of time until administration of analgesic drugs, the proportion of patients requiring analgesic drugs during the initial 24 post-operative hours, and the amounts of post-operative analgesic drugs. A Bayesian inference supporting direct statements about the probability of the magnitude of an effect was used to compare the effects size.


RESULTS
Neostigmine increased the duration of analgesia by 9.96 h (95% confidence interval: 7.75 to 12.16), as compared with 3.68 h (2.65 to 4.7) with clonidine and 4.45 (2.84 to 6.07) with tramadol. There is a 95% probability that neostigmine increases the duration of post-operative analgesia by more than 8 h, clonidine by more than 2.8 h, and tramadol by more than 3.25 h, as compared with local anesthetics alone. The odds ratios for the proportion of patients requiring analgesic drugs were 0.22 [0.13 to 0.37] for clonidine and 0.28 [0.10 to 0.75] for neostigmine. With tramadol, there was no statistically significant difference. All three additives reduced the amounts of post-operative analgesic drugs. Neostigmine and tramadol increase the probability for post-operative nausea or vomiting (PONV).


CONCLUSIONS
Neostigmine provides the longest post-operative analgesia. With clonidine, the duration of analgesia is shorter and sedation is increased, but the probability for PONV could be decreased.
Department of Anaesthesia, CUB Hopital Erasme, Brussels, Belgium. eengelma@ulb.ac.be
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Engelman
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Marsala
D000759:Adjuvants, Anesthesia / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000293:Adolescent; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000701:Analgesics, Opioid / Q000008:administration & dosage; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D000779:Anesthetics, Local / Q000008:administration & dosage; D001499:Bayes Theorem; D002648:Child; D002675:Child, Preschool; D003000:Clonidine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D007223:Infant; D007430:Intraoperative Care; D009388:Neostigmine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D010149:Postoperative Pain / Q000188:drug therapy*; D020250:Postoperative Nausea and Vomiting / Q000139:chemically induced; D013997:Time Factors; D014147:Tramadol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D016055:Urinary Retention / Q000139:chemically induced
D000759:Adjuvants, Anesthesia; D000700:Analgesics; D000701:Analgesics, Opioid; D018685:Anesthetics, Inhalation; D000779:Anesthetics, Local; D006993:Hypnotics and Sedatives; D009388:Neostigmine; D014147:Tramadol; D003000:Clonidine