Failed tracheal intubation during obstetric general anaesthesia: a literature review

Abstract

We reviewed the literature on obstetric failed tracheal intubation from 1970 onwards. The incidence remained unchanged over the period at 2.6 (95% CI 2.0 to 3.2) per 1000 anaesthetics (1 in 390) for obstetric general anaesthesia and 2.3 (95% CI 1.7 to 2.9) per 1000 general anaesthetics (1 in 443) for caesarean section. Maternal mortality from failed intubation was 2.3 (95% CI 0.3 to 8.2) per 100000 general anaesthetics for caesarean section (one death per 90 failed intubations). Maternal deaths occurred from aspiration or hypoxaemia secondary to airway obstruction or oesophageal intubation. There were 3.4 (95% CI 0.7 to 9.9) front-of-neck airway access procedures (surgical airway) per 100000 general anaesthetics for caesarean section (one procedure per 60 failed intubations), usually carried out as a late rescue attempt with poor maternal outcomes. Before the late 1990s, most cases were awakened after failed intubation; since the late 1990s, general anaesthesia has been continued in the majority of cases. When general anaesthesia was continued, a laryngeal mask was usually used but with a trend towards use of a second-generation supraglottic airway device. A prospective study of obstetric general anaesthesia found that transient maternal hypoxaemia occurred in over two-thirds of cases of failed intubation, usually without sequelae. Pulmonary aspiration occurred in 8% but the rate of maternal intensive care unit admission after failed intubation was the same as that after uneventful general anaesthesia. Poor neonatal outcomes were often associated with preoperative fetal compromise, although failed intubation and lowest maternal oxygen saturation were independent predictors of neonatal intensive care unit admission.

Obstetric Anaesthetists’ Association and Difficult Airway Society Guidelines for the Management of Difficult and Failed Tracheal Intubation in Obstetrics

“…We initially performed a comprehensive review of the literature on failed tracheal intubation following rapid sequence induction of obstetric general anaesthesia [9]. Further workstreams included a national OAA survey of lead obstetric anaesthetists to clarify aspects of management of difficult and failed intubation [12], and a secondary analysis of neonatal outcomes from the UK Obstetric Surveillance System (UKOSS) obstetric failed tracheal intubation database [9].…”

“…Although maternal safety is a greater priority for the anaesthetist than fetal, women willingly accept some risk to themselves to ensure a good neonatal outcome [46]. Fetal condition is likely to be maintained during a delay in the majority of cases [9]; at caesarean section for fetal bradycardia in one study, there was a significant decline in neonatal pH with increasing bradycardia-delivery interval only in cases with an irreversible cause for the bradycardia, in contrast to those with a potentially reversible or unascertained cause [47]. Irreversible causes include major placental abruption [48], fetal haemorrhage (e.g.…”

“…sustained [9]. Persistent failure to ventilate despite optimal attempts using a SAD and/or facemask may be caused by intrinsic patient factors; however, laryngeal spasm and poor chest wall compliance are potentially modifiable and may be improved by ensuring full neuromuscular blockade.…”

El Manejo de la Intubación traqueal difícil y/o fallida en anestesia obstétrica

“…La evaluación de la vía aérea no siempre predice dificultades, y de hecho dos tercios de los pacientes en esta revisión de Kinsela, fueron reportados sin dificultades en la vía aérea en la evaluación, pero se comportaron como intubaciones difíciles 2 . Tanto como la predicción de dificultad en la intubación traqueal, la facilidad de ventilación con mascarilla facial, inserción de dispositivos supraglóticos y abordaje quirúrco cervical, deben ser considerados, cualquier vía aérea difícil predicta debe ser identificada durante el período antenatal, y un plan específico de manejo, debe ser delineado.…”

Management of the obstetric airway — time for a paradigm shift (or two)?

“…[3][4][5] In this edition of the International Journal of Obstetric Anesthesia, Kinsella et al have written a review of management of failed tracheal intubation during obstetric general anesthesia (GA) covering 45 years of published data with analysis of what has/has not changed. 6 The review was initiated as part of the background information that will be used by the UK's Obstetric Anaesthetists' Association (OAA) and Difficult Airway Society (DAS) as they work on a difficult airway algorithm specific to the obstetric patient.…”