Failed intubation in obstetrics: has the incidence changed recently?

Abstract

Editor—Over the years, airway problems have dominated anaesthesia related maternal mortality. Failed intubation in parturients is more common than the general surgical population with incidences in the obstetric population being as high as 1 in 250.1Barnardo PD Jenkins JG Failed tracheal intubation in obstetrics: a 6 year review in a UK region.Anaesthesia. 2000; 55: 685-694Crossref PubMed Scopus (152) Google Scholar2Hawthorne L Wilson R Lyons G Dresner M Failed intubation revisited: 17 yr experience in a teaching maternity unit.Br J Anaesth. 1996; 76: 680-684Crossref PubMed Scopus (224) Google Scholar We report our local experience. As a part of an ongoing audit we collect data about failed intubation and these, with other data, are recorded in the annual hospital report. We analysed the data for the 16 yr from 1988 to 2004. During this period, 91 758 women gave birth in our institution. Of these, 19 600 were delivered by Caesarean section (CS) either electively or as an emergency. Though the annual number of CS increased from 984 in 1988 to 1531 in 2003–04, in keeping with national practice,3NHS Maternity Statistics England: 2002–03. Bulletin 10. Government Statistical Services, Department of Health, 2004Google Scholar the numbers performed under general anaesthesia decreased from 644 to 235 in the same years. There were 11 failed intubations during this period in 5968 general anaesthetics administered for CS giving an incidence of 1 in 543 (Table 1). There were no failed intubations in general anaesthetics administered for other purposes in parturients. We split our data into before and after the introduction of Calman training in 1996. Though the incidence of failed intubation increased from 1 in 770 (1988–95) to 1 in 353 (1996–2004), these data are not statistically significant (χ2-test). There was no mortality related to airway problems during this period. On four occasions a laryngeal mask airway (LMA®) †LMA® is the property of Intavent Ltd. was documented as being used successfully, three times since 1996. †LMA® is the property of Intavent Ltd.Table 1Total number of deliveries, Caesarean section, general anaesthesia (GA) and failed intubation. (Year 1990–91 shows details for 15 month period as the hospital report changed from calendar year to fiscal year for administrative purposes)YearDeliveries (n)Caesarean section (n)Caesarean section under GA (n)Failed intubation (n)1988492798464401989451089848501990–916071109955001991–92486593248611992–93460488146511993–946236103842611994–95591798838021995–965882115441201996–976128125839101997–986150137328521998–996096142031211999–006071158531112000–015832155212802001–025913139321002002–036136151424812003–04642015312351 Open table in a new tab There have been concerns expressed about general anaesthesia training for obstetrics4Johnson RV Lyons GR Wilson C Robinson APC Training in obstetric general anaesthesia: a vanishing art?.Anaesthesia. 2000; 55: 163-183Crossref PubMed Scopus (9) Google Scholar because of the increased use of regional anaesthesia, reduction in working hours and training time. This restricts the training opportunities for general anaesthesia, which when required are often in urgent situations. Though the use of regional anaesthesia and the introduction of the LMA in the failed intubation drill may have contributed to the reduction of anaesthesia related maternal mortality in the 1990s, airway problems in obstetric anaesthesia can not be ignored. Although our figures are not statistically significant, they highlight the need for proper national critical incident collection (with denominator data) to be aware of such concerns more quickly. Although the Royal College of Anaesthetists has produced a teaching CD-ROM about general anaesthesia for obstetrics to help solve the problem of airway management, and simulator teaching5Goodwin MWP French GWG Simulation as a training and assessment tool in the management of failed intubation in obstetrics.Int J Obstet Anesth. 2001; 10: 273-277Abstract Full Text PDF PubMed Scopus (34) Google Scholar may help, there is no real substitute for practical teaching in obstetric units.