Chloroprocaine Bupivacaine

Some other anesthetics with similar structures are prilocaine, tetracaine, ropivacaine, bupivacaine, chloroprocaine, and mepivacaine ... 

Chloroprocaine hydrochloride [3858-89-7] is characterized by low potency, rapid onset, short duration of action, and low systemic toxicity. It is indicated for infiltration anesthesia at 1—2% and for extradural anesthesia at 2—3% when short surgical procedures are performed under regional anesthesia. Chloroprocaine may be mixed with long duration agents such as bupivacaine (22, R = n-Q [) to afford a more rapid onset and shorter duration of action than bupivacaine alone. 

The primary site of action of epidurally administered agents is on the spinal nerve roots. As with spinal anesthesia, the choice of drug to be used is determined primarily by the duration of anesthesia desired. However, when a catheter has been placed, short-acting drugs can be administered repeatedly. Bupivacaine is typically used when a long duration of surgical block is needed. Lidocaine is used most often for intermediate length procedures chloroprocaine is used when only a very short duration of anesthesia is required. 

Epidural anesthesia This term is understood to be an introduction of local anesthetic into the spinal cord membrane of the intervertebral space. It is used during obstetrical and gynecological interventions that do not require a fast development of anesthesia. Drugs such as lidocaine, mepivacaine, bupivacaine, ethidocaine, and chloroprocaine are used for this purpose. 

The choice of local anesthetic for infiltration, peripheral nerve blocks, and central neuraxis (spinal/epidural) blockade is usually based on the duration of action required. Procaine and chloroprocaine are short-acting lidocaine, mepivacaine, and prilocaine have an intermediate duration of action and tetracaine, bupivacaine, levobupivacaine, and ropivacaine are long-... 

Local anesthetic-induced seizures have been reported more often with bupivacaine, particularly in combination with chloroprocaine (SEDA-20, 123). Ropivacaine-induced seizures have also been reported (21,22). 

Metabolism of ester local anesthetics is carried out by plasma cholinesterases and may be rapid. Procaine and chloroprocaine have half-lives of only 1-2 minutes. The amides are hydrolyzed in the liver and have half-lives from 1.8 hours to 6 hours. Bupivacaine and ropiva-caine are very lipid-soluble and long-acting local anesthetics. Liver dysfunction may increase the elimination half-life of amide local anesthetics. 

Mixtures of local anaesthetics are sometimes used to exploit the most useful characteristics of each drug. This normally seems to be safe although it is sometimes claimed that it increases the risk of toxicity. There is a case report of a man who developed toxicity when bupivacaine and mepivacaine were mixed together. Spinal bupivacaine followed by epidural ropivacaine may also interact to produce profound motor blockade. However, the effectiveness of bupivacaine in epidural anaesthesia may be reduced if it is preceded by chloroprocaine. 

A study on the use of chloroprocaine 3%, bupivacaine 0.5% or a mixture of chloroprocaine 1.5% with bupivacaine 0.375% in obstetric epidural anaesthesia found that time to onset of analgesia, time to maximum analgesia, and effectiveness of analgesia were similar irrespective of the treatment regimen. Bupivacaine 0.5% alone had a longer duration of action than chloroprocaine or the mixture of anaesthetics. Another study found that lidocaine did not affect the pharmacokinetics of bupivacaine. ... 

Cohen SE, Thurlow A, Comparison of a chloroprocaine-bupivacaine mixture with chloroprocaine and bupivacaine used individually for obstetric epidural analgesia. Anesthesiology 0979)51,288-92,... 

Hodgkinson R, Husain FJ, Bluhm C, Reduced effectiveness of bupivacaine 0.5% to relieve labor pain after prior injection of chloroprocaine 2%, Anesthesiolo (1982) 57, A201. 

Chen B-J, Kwan W-F, pH is not a determinant of 2-chloroprocaine-bupivacaine interaction a clinical study, RegAnesth (1990) 15 (Suppl 1), 25,... 

Chloroprocaine can reduce the efficacy of epidural morphine and fentanyl analgesia. Bupivacaine may enhance the local anaesthetic effect of fentanyl, but does not appear to affect respiration. Similarly, Udocaine does not appear to increase respiratory depressant effects of morphine. However, two cases of respiratory depression have been reported with Udocaine and opioids. Morphine given as an intravenous bolus does not alter Udocaine serum levels given as a continuous intravenous infusion. 

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