Anticipated difficult airway during obstetric general anaesthesia: narrative literature review and management recommendations.

Abstract

We reviewed the literature on management of general and regional anaesthesia in pregnant women with anticipated airway difficulty. We identified 138 publications comprising 158 cases; these either described equipment or techniques for the provision of general anaesthesia, or the management of women with regional analgesia or anaesthesia, with the aim of avoiding general anaesthesia. Most of the former group described women requiring caesarean section alone, or in combination with other surgery, which was sometimes airwayrelated. Management techniques were largely similar to those in non-obstetric patients requiring surgery who have airway difficulties, although suggested differences related to physiological changes of pregnancy and avoidance of nasal intubation. In the reports discussing regional anaesthesia, consideration was often given to the possible requirement for urgent out-of-hours anaesthetic intervention, and the predicted difficulty of management of general anaesthesia should it be required. In a number of reported cases, multidisciplinary planning led to the conclusion that elective caesarean section should be performed in order to avoid emergency airway management. Based on this literature review, we advise antenatal planning that includes: assessment of the patient's clinical characteristics; consideration of the equipment and personnel available to provide safe airway management out-of-hours; and elective caesarean section should these be lacking. If general anaesthesia is required, a risk assessment must be made as to the probability of safe airway management after the induction of anaesthesia, and awake tracheal intubation should be used if this cannot be assured. Decision aids are provided to illustrate these points. Online appendices include a comprehensive compendium of case reports on the management of a number of rare syndromes and airway conditions.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

“…Antenatal airway screening of all obstetrical patients should ideally occur with multidisciplinary consultation when indicated. 253 , 254 Should a parturient possess a non-reassuring airway, early epidural catheter placement and testing should occur during labour. If CD under general anesthesia is required, the airway should be re-assessed, recognizing the dynamic nature of the airway during labour.…”

Kreislaufstillstand unter besonderen Umständen

“…Schwangere Patientinnen haben ein erhöhtes Risiko für Regurgitation und Aspiration sowie ein erhöhtes Risiko für eine fehlgeschlagene Intubation [ 645 – 647 ]. Der Atemweg soll gemäß den aktuellen ALS-Leitlinien gemanaged werden (Beutel-Maske, supraglottischer Atemweg, Trachealtubus, je nach den Fähigkeiten des Retters).…”

Consideraciones en el manejo de la vía aérea en embarazadas

“…La evaluación orientada a predecir la posibilidad de ventilar y oxigenar es más relevante que la intubación; si bien no existe literatura suficiente que defina predictores de "ventilabilidad" en pacientes embarazadas, se podrían extrapolar de otros grupos, puesto que los factores son similares en pacientes no grávidas (2,4). Algunos predictores de imposibilidad para ventilación con máscara facial son: obesidad (índice de masa corporal mayor de 30 kg/m 2 ), Mallampati III (solo son visibles el paladar duro y blando) o IV (solamente se observa el paladar duro), limitación severa para la protrusión mandibular, roncar, ser edéntula, preeclampsia, entre otros (2,4,10). En cuanto a la evaluación para predecir la facilidad de la laringoscopía e intubación, algunas variables que condicionan a que sea un procedimiento complejo son las siguientes: cuello corto, cuello grueso (más de 17 pulgadas de circunferencia), incisivos superiores prominentes, micrognatia, Mallampati III o IV, distancia tiromentoniana disminuida (menos de 3 traveses de dedo), dificultad para la flexoextensión del cuello, paladar muy alto o muy bajo, entre otros (2,4,10,11).…”