Evaluation of airway changes in pregnancies BY ultrasonography

During pregnancy, a peripheral edema table is observed, which is thought to be especially related to progesterone increase and becomes more prominent in the last trimester. This edema table can also be viewed on the upper airway. While the results of the routine tests we use in preoperative airway evaluation can be similar to the pre-pregnancy period at the beginning of pregnancy, it may change in the last trimester. In our study, we investigated whether there was a correlation between the routine tests used in the upper airway evaluation and the 3 measurements we performed on the upper airway ultrasonography (distance from skin-to hyoid bone, ditance from skin-to epiglottis, distance from skin-to anterior commissure). Ethical approval was obtained from Manisa Celal Bayar University Faculty of Medicine Local Ethics Committee. 60 cases diagnosed with pregnancy by Obstetrics and Gynecology clinic were included in the study. These pregnant women were informed about the content of the informed thoroughly with informed consent forms on the first evaluation date. The inclusion criteria were: being a woman between the ages of 18 and 45, diagnosed with pregnancy, the current pregnancy was not greater than 10 weeks during the first assessment. Those with a previous history of difficult airway, those who had undergone surgery to disrupt the anatomy, those with a gestational week of more than 10 weeks in the first evaluation were not included in the study group. 9 pregnant cases were excluded from the study because they refused to do ultrasonography after explaining the content of the detailed voluntary consent form. The research data were evaluated using the SPSS 15.0 (Statistical Package for Social Sciences) statistics program. Descriptive statistics showed number and percentage distributions, mean ± standard deviation. Upper airway measurements (distance between skin-hyoid bone, distance between skin-epiglote, distance between skin-anterior commissure) 52 in 4 different periods (6-10th weeks, 16-20th weeks, 26-30thweeks, after 34th week) done. Modified mallampathy score, upper lip bite test, Wilson risk score, mandibular protrusion grade were also examined in the first trimester. The modified mallampathy score was also recorded in repeated measurements. After measurements, it was observed that the BMI values of the patients who had a high (3-4) modified mallampathy score while the modified mallampathy score was low (1-2) during first evaluation were significantly higher than those who did not change categorically in the mallampathy score(p=0,002). There was a weak yet statistically significant correlation between TMD-SMD(r=0,308, p=0,017). According the ultrasonography measurements, the distance between the skin and the hyoid bone and the distance between the skin and the epiglott were observed to be positively correlated (r=0,509, p<0,001). When the cases are divided into two groups as low (1-2) or high (3-4) values obtained in MMS in the first and last measurement, there weas no statistically significant diffence between these two groups in terms of TMD, SMD, Wilson risk scores and 3 ultrasonography measurements (distance between skin-hyoid bone, distance between skinepiglote, distance between skin-anterior commissure). When patients who had lowmodified mallampaty scores (1-2) in the first measurement and high scores (3-4) in the last measurement were compared with the cases whose scores did not change through measurements; no significant difference was found between these two groups in terms of TMD, SMD, Wilson risk scores and 3 measurements (distance between skin-hyoid bone, distance between skin-epiglote, distance between skin-anterior commissure). In conclusion, we think that use of ultrasonography in the evaluation of upper airway in pregnant women, may be beneficial to use it in addition to upper airway evaluation tests and these measurements are independent of each other.However, we conclude that further studies are needed in large case series.