Evaluation of respiratory mechanics in pregnant women

ABSTRACT The respiratory function is one of the organic processes most affected by pregnancy, and it can be evaluated by cirtometry and manovacuometry. The changes in thoracic expansibility and respiratory pressures during pregnancy of healthy women were verified. This is a prospective, descriptive and analytic study. Ninety three pregnant women who attended health unities from Ponta Grossa (Brazil) have participated. They were divided in three groups, according to the gestational period: G1 (first trimester), G2 (second trimester) and G3 (third trimester). The following evaluations were performed with each woman: cirtometry in three points and manovacuometry. The thoracic mobility presented reduction while the pregnancy progressed (respiratory coefficient: armpit line - G1>G2>G3, middle line - G1>G2>G3, xiphoid appendix - G1>G2>G3; inspiration-rest: armpit line - G1>G2>G3, middle line - G1>G2>G3, xiphoid appendix - G1>G2>G3; rest-expiration: armpit line - G1>G2>G3, middle line - G1>G2>G3, xiphoid appendix - G1>G2>G3), in all the cases p<0.01. The maximum inspiratory and expiratory pressures decreased from G1 to G2 (p<0.01 in both cases) and to G3 (p<0.01 in both cases). We concluded that the respiratory muscular strength and the thoracic mobility present reduction with pregnancy progression.