Document Detail

Mechanisms and management of an incomplete epidural block for cesarean section.
MedLine Citation:
PMID:  12698831     Owner:  NLM     Status:  MEDLINE    
Epidural blockade is an important option for anesthesia in parturients undergoing abdominal delivery. Despite the multiple benefits of this method, there is at least one significant downside--a relatively high occurrence of unsatisfactory anesthesia that requires intervention. Depending on the presumed mechanism of epidural block failure and other clinically relevant factors (e.g., timing of diagnosis, urgency of the procedure, and so forth), certain effective measures are recommended to successfully manage this demanding situation. In general, it is important to make every effort to make the pre-existing epidural effective or replace it with another regional technique, because overall, regional anesthesia is associated with significantly lower maternal mortality. It is important to identify a dysfunctional epidural block preoperatively before a maximum volume of local anesthetic has been administered. If catheter manipulation does not produce substantial improvement, and there is no time constraint, it is safe and reasonable to replace the epidural catheter. However, risks associated with excessive volume of local anesthetic should be kept in mind. Additional epidural injections or a second catheter placement might be considered under special circumstances. Single-shot spinal anesthesia after a failed epidural may provide fast onset and reliable surgical anesthesia. Available data, although limited and contradictory, suggest the possibility of unpredictably high or total spinal anesthesia. Many authors, however, believe that appropriate precautions and modifications in technique make this a safe alternative. These modifications include limiting the amount of epidural local anesthetic administered when diagnosing a nonfunctioning epidural and decreasing the dose of intrathecal local anesthetic by 20% to 30%. If there is no documented block when the spinal is inserted, and more than 30 minutes have passed from the last epidural dose, it is probably safe to use a normal dose of local anesthetic. Continuous spinal anesthesia with a macro catheter might be a dependable alternative, particularly if large amounts of local anesthetic have already been used or the patient's airway is a cause for concern. Although there are no reports of combined spinal epidural anesthesia being used in this context, it would appear to be an attractive alternative. It allows the anesthesiologist to give smaller doses intrathecally, while still offering the flexibility of augmenting the block if needed. When inadequate epidural block becomes apparent during surgery there are limited alternatives. Depending on the origin and the pattern of inadequate anesthesia, options may include psychological support, supplementation with a variety of inhalational and intravenous agents, and local anesthetic infiltration. Induction of general anesthesia is typically left as a backup option, but must be strongly considered if the patient continues to have pain/discomfort.
Dmitry Portnoy; Rakesh B Vadhera
Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  Anesthesiology clinics of North America     Volume:  21     ISSN:  0889-8537     ISO Abbreviation:  Anesthesiol Clin North America     Publication Date:  2003 Mar 
Date Detail:
Created Date:  2003-04-17     Completed Date:  2003-05-01     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  8810131     Medline TA:  Anesthesiol Clin North America     Country:  United States    
Other Details:
Languages:  eng     Pagination:  39-57     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Anesthesia, Epidural* / methods
Anesthesia, Obstetrical* / methods
Anesthesia, Spinal
Cesarean Section*
Nerve Block* / methods
Risk Factors


Previous Document:  New local anesthetics. Are they worth the cost?
Next Document:  Misconceptions about neuraxial analgesia.