To the Editor:—
We read the article by Mhyre and colleagues with interest.1
Although in the United Kingdom problems with tracheal intubation during obstetric general anesthesia remain the leading cause of death,2
there were no cases in their series from 1985 to 2003 suggesting that anesthesia providers in Michigan have been able to address this risk successfully. This is especially commendable as the rate of general anesthesia deaths, largely resulting from intubation problems or aspiration, was stable in the United States from 1979 to 1990.3
Many deaths in Mhyre et al.
’s article were related to problems occurring some time after the induction of anesthesia. There are considerable differences between the United States and United Kingdom in anesthesia staffing both in the operating room and on the delivery suite, but the United Kingdom Confidential Enquiries into Maternal Deaths have repeatedly highlighted the vital role of the anesthesiologist in overall maternity care rather than just during surgery.2
However, we were surprised that there was no mention of regional anesthesia problems in the abstract or the accompanying editorial,4
as this was the primary cause of three of four anesthetic-related deaths during cesarean delivery. Of the eight patients who died from anesthesia-related causes, three were in the first or second trimester. The five patients in their third trimester all underwent cesarean delivery. One patient who had received a spinal anesthetic died 9 h postoperatively, related to systemic morphine treatment. The type of anesthetic is irrelevant to the death as the patient would likely have had patient-controlled analgesia even if she had had general anesthesia. Only one of the four women in whom the sequence of adverse events started during surgery had a primary general anesthetic, whereas three had regional anesthesia: a respiratory event at the end of surgery with a spinal, a cardiopulmonary arrest with an epidural test dose (presumably from accidental spinal placement), and a cardiac arrest with a spinal. Deaths from obstetric regional anesthesia are rare,5
and regional anesthesia is much safer than general anesthesia.3,6
However, this rarity means that the risk of cardiac arrest may be forgotten and need to be relearned.7
We need to recognize that cardiovascular collapse8
and unconsciousness from high block9
may occur suddenly at any stage during regional anesthesia and lead to morbidity or death unless managed promptly and effectively.5,9
S. Michael Kinsella, M.B., B.S., F.C.A.R.C.S.I.,*
Daryl Dob, B.Sc., M.B., B.S., F.R.C.A.
Anita Holdcroft, M.B., Ch.B., M.D., F.R.C.A.
*St. Michael’s Hospital, Bristol, United Kingdom. firstname.lastname@example.org
1. Mhyre JM, Riesner MN, Polley LS, Naughton NN: A series of anesthesia-related maternal deaths in Michigan, 1985-2003. Anesthesiology 2007; 106:1096–104
2. The Confidential Enquiries into Maternal and Child Health. Why Mothers Die 2000-2002. The Sixth Report on the Confidential Enquiries into Maternal Deaths in the United Kingdom. London, RCOG Press, 2004
3. Hawkins JL, Koonin LM, Palmer SK, Gibbs CP: Anesthesia-related deaths during obstetric delivery in the United States, 1979-1990. Anesthesiology 1997; 86:277–84
4. D’Angelo R: Anesthesia-related maternal mortality: A pat on the back or a call to arms? Anesthesiology 2007; 106:1082–4
5. Kinsella SM, Dob D, Holdcroft A. Regional anaesthesia, Crises in Childbirth: Why Mothers Survive. Lessons from the Confidential Enquiries into Maternal Deaths. D Dob, G Cooper, A Holdcroft (Eds). Oxford, Radcliffe Publishing, 2007.
6. Shibli KU, Russell IF: A survey of anaesthetic techniques used for caesarean section in the UK in 1997. Int J Obstet Anaesth 2000; 9:160–7
7. Keats AS: Anesthesia mortality: A new mechanism. Anesthesiology 1988; 68:2–4
8. Kinsella SM, Tuckey JP: Perioperative bradycardia and asystole: Relationship to vasovagal syncope and the Bezold-Jarisch reflex. Br J Anaesth 2001; 86:859–68
9. Yentis SM, Dob DP: High regional block: The failed intubation of the new millennium? Int J Obstet Anaesth 2001; 10:159–61
© 2008 American Society of Anesthesiologists, Inc.