Comparison of Classic and Sequential Spinal Techniques for Preventing Hypotension During Cesarean Delivery.

Occurrence of maternal hypotension within 15 minutes after intrathecal injection, defined as a systolic blood pressure (SBP) decrease greater than 20% from baseline or an absolute SBP below 90 mmHg. This outcome directly measures the hemodynamic stability achieved by each spinal technique.

The interval between the time of intrathecal injection and the first recorded episode of hypotension. This reflects how long each technique maintains stable blood pressure before any drop occurs.

The total count of discrete hypotensive events occurring within the observation period after spinal anesthesia. This indicates the frequency and severity of blood pressure fluctuations.

The total amount of phenylephrine and/or ephedrine administered to correct hypotension during the observation period, serving as an indirect measure of hemodynamic stability.

Determines the highest dermatomal sensory level achieved and the time required to reach the T4 level, indicating block quality and onset characteristics of the anesthetic technique. Maximal sensory block level is assessed by testing loss of sensation to cold or pinprick over the trunk in a cephalad-caudal direction and mapping the highest blocked dermatome (e.g., using an alcohol swab or pin along the midline and comparing to known dermatomal levels such as T4 at the nipple line). Time to T4 is measured as the interval in minutes from completion of intrathecal injection to the first assessment at which loss of sensation reaches the T4 dermatome, documented with the same stimulus and dermatomal map.

Incidence of intraoperative nausea or vomiting related to hypotension or anesthetic effect.

Maternal satisfaction will be evaluated using a 5-point Likert scale addressing analgesia adequacy, comfort, and overall anesthesia experience. Each participant will rate her satisfaction as follows: 1 for "very dissatisfied," indicating poor pain control and significant discomfort; 2 for "dissatisfied," reflecting partial relief with ongoing discomfort; 3 for "neutral," denoting acceptable but unremarkable pain relief; 4 for "satisfied," representing good pain control with minimal discomfort; and 5 for "very satisfied," indicating excellent analgesia and a fully positive anesthesia experience.

Measures neonatal wellbeing through 1-minute and 5-minute Apgar scores and umbilical artery blood pH to assess the effect of maternal hemodynamics on fetal oxygenation.