The Relationship Between the Patient's Abdominal Circumference, Symphysis Pubis-Fundal Distance, and Vertebral Column Length with the Incidence of Hypotension and the Level of Block in Cesarean Section Operations Performed Under Spinal Anesthesia

INTRODUCTION: The incidence of hypotension in cesarean section operations performed with spinal anesthesia varies between 55-90%. In this study, the relationship between the patient's abdominal circumference, symphyseal fundal height, and vertebral column length with the incidence of hypotension and the level of block in cesarean section operations performed under spinal anesthesia was investigated.
METHODS: The prospective, single-center study was conducted with patients who had undergone cesarean section with spinal anesthesia at the Training and Research Hospital. Pregnant and ASA II group patients older than 37 weeks who were to undergo cesarean section with spinal anesthesia were included in the study. Patients with multiple pregnancies, patients with premature rupture of membranes, preterm patients, and patients in active labor were excluded from the study. Those with diagnoses of abnormal presentation, polyhydramnios, oligohydramnios, macrosomic babies, and intrauterine growth retardation were also excluded from the study. Abdominal circumference was measured at the umbilicus level at the end of expiration in the supine position. Vertebral column length was measured and recorded from the C7 vertebra to the sacral hiatus. The distance of the patient from the symphysis pubis to the highest point of the uterine fundus in the supine position was measured and recorded. Spinal anesthesia was performed in the sitting position with a 26G Quincke spinal needle for the first time through the L4-5 interval and 2 mL of 0.5% hyperbaric bupivacaine was administered. When the block reached T6, the operation was started. Electrocardiogram (ECG), SpO2, and arterial blood pressure were monitored, and the first values were recorded.
RESULTS: A total of 98 parturient patients were included in this study. Overall, the incidence of hypotension was 87.78% (87 out of 98 parturients). Symphyseal fundal height correlated positively with spinal blockade levels at each different time point except for "Min. 4".
DISCUSSION AND CONCLUSION: Symphyseal fundal height is a sensitive marker to determine the risk of hypotension after spinal anesthesia. We found that the symphyseal fundal height is a more sensitive marker for hypotension that will develop after spinal anesthesia compared to the other two parameters.