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Maternal respiratory function following normal vaginal delivery
A Gupta1, A Johnson, A Johansson
1Department of Anaesthesiology, University Hospital, S-581 85 Linköping, Sweden.
Forced expiratory volume (FEV(1)) forced vital capacity (FVC), peak expiratory flow (PEF) and maximum expiratory pressure (P(E)max) were measured in 11 healthy women 2, 4, 8, 24, 48 and 72 hours after normal vaginal delivery and repeated after 6-8 weeks. There was a significant (P<0.05) reduction in the P(E)max up to 4 hours after delivery. In contrast, there was no significant reduction in FEV(1) or FVC at any of the time periods, and PEF showed a significant reduction only at 2 hours after delivery. This indicates that P(E)max is a more sensitive measure of respiratory muscle strength and that this is reduced for at least 4 hours after delivery. Any anaesthetic given during this period should take into consideration that the ability to cough effectively may be impaired.
Forced expiratory volume (FEV(1)) forced vital capacity (FVC), peak expiratory flow (PEF) and maximum expiratory pressure (P(E)max) were measured in 11 healthy women 2, 4, 8, 24, 48 and 72 hours after normal vaginal delivery and repeated after 6-8 weeks. There was a significant (P<0.05) reduction in the P(E)max up to 4 hours after delivery. In contrast, there was no significant reduction in FEV(1) or FVC at any of the time periods, and PEF showed a significant reduction only at 2 hours after delivery. This indicates that P(E)max is a more sensitive measure of respiratory muscle strength and that this is reduced for at least 4 hours after delivery. Any anaesthetic given during this period should take into consideration that the ability to cough effectively may be impaired.
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