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Correspondence  |   October 2004
Cardiac Toxicity from 3% 2-Chlorprocaine
Author Affiliations & Notes
  • Franklyn Cladis, M.D.
    *
  • * University of Pittsburgh School of Medicine, The Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania.
Article Information
Correspondence
Correspondence   |   October 2004
Cardiac Toxicity from 3% 2-Chlorprocaine
Anesthesiology 10 2004, Vol.101, 1036. doi:
Anesthesiology 10 2004, Vol.101, 1036. doi:
In Reply:–
Drs. Shroff and Mayhew are concerned that the epidural loading dose of 3% 2-chloroprocaine was too large because plasma cholinesterase concentrations are reduced in neonates and infants.1 However, the half-life of 2-chloroprocaine is of such short duration that increasing the dose has no significant clinical impact on complications. In our case report, we reported the half-life of chloroprocaine to be 1–4.5 min.2 However, others have reported the plasma half-life to be less than 60 s.3,4 Plasma chloroprocaine concentrations have been measured in pediatric patients receiving continuous epidural infusions. Former preterm infants undergoing inguinal hernia repair received loading doses of 1 ml/kg 2-chloroprocaine, 3% (30 mg/kg), via  an indwelling caudally placed epidural catheter and were then given infusions at a minimum rate of 30 mg · kg−1· h−1.5 The mean cumulative dose of 2-chloroprocaine infused over 95 ± 35 min was 84 ± 30 mg · kg−1· h−1. The plasma chloroprocaine concentrations were 0 mg/ml in four patients and 0.5 mg/ml in one patient, and there was no evidence of neurotoxicity or cardiovascular toxicity.5 Suggested loading doses of epidurally administered 2-chloroprocaine in the pediatric regional literature have ranged from 30 to 60 mg/kg.3,4 
Based on the above data, the loading dose of 30 mg/kg was clearly appropriate. However, as we highlighted in our case report, pediatric epidurals should be tested before administration of a loading dose of local anesthetic to minimize the risk of unintentional intravascular injections and subsequent toxicity.
* University of Pittsburgh School of Medicine, The Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania.
References
Zsigmond EK, Downs JR: Plasma cholinesterase activity in newborns and infants. Can Anaesth Soc J 1971; 18:278–85Zsigmond, EK Downs, JR
Kuhnert BR, Kuhnert PM, Philipson EH, Syracuse CD, Kaine CJ, Yun CH: The half-life of 2-chloroprocaine. Anesth Analg 1986; 65:273–8Kuhnert, BR Kuhnert, PM Philipson, EH Syracuse, CD Kaine, CJ Yun, CH
Tobias JD, Sandra L, O’Dell N, Pietsch JB, Neblett WW: Continuous regional anaesthesia in infants. Can J Anaesth 1993; 40:1065–8Tobias, JD Sandra, L O’Dell, N Pietsch, JB Neblett, WW
Gunter JB: Benefit and risks of local anesthetics in infants and children. Pediatr Drugs 2002; 4:649–72Gunter, JB
Henderson K, Sethna NF, Berde CB: Continuous caudal anesthesia for inguinal hernia repair in former preterm infants. J Clinical Anesthesia 5:129–33Henderson, K Sethna, NF Berde, CB