Airway changes in pregnant women before and after delivery

High incidence of difficult or failed intubation in obstetric patients is still a major problem to challenge anaesthesiologists. Although the probability of difficult intubation is impossible to predict preoperatively, some simple, practical bedside tests may help. This study used five simple tests in an attempt to better evaluate airway changes in pregnant women before and after delivery.

Pregnant women from the ASA I-II group who were planning to undergo a normal vaginal delivery were evaluated as to the possibility of experiencing difficult intubation. Mallampati scores, thyromental distance, sternomental distance, mouth opening, and the degree of neck extension were recorded just before delivery and 24 h after delivery.

Significant differences were seen in the pre- and post-delivery measurements (p < 0.05). Before delivery, Mallampati scores I, II, III, IV were 35, 24, 2, 0, respectively, and 24 h after delivery became 46, 15, 0, 0, respectively.

Within 24 h after delivery, Mallampati scores changed in one-third (n 21, 36.6%) of the patients. Significant differences between the two measurements of thyromental and sternomental distances, mouth opening, and the degree of neck extension confirm difficult airway management in pregnant women.