The Ultrasound Guided Versus Land-mark Location Method for Performing Spinal Anesthesia in Obese Parturients

The Ultrasound Guided Versus Land-mark Location Method for Performing Spinal Anesthesia in Obese Parturients

Comparison of Ultrasound and Anatomical Land-mark Method in Spinal Anesthesia for Elective Cesarean Section in Obese Parturients With BMI ≥ 40 kg/m2. A Randomized Controlled Trial

This study will be investigated whether an ultrasound-assisted technique is better than a classical land-mark technique to facilitate spinal anesthesia in the lateral position in morbidly obese pregnant women with BMI ≥ 40 who will undergo elective cesarean section. The primary objective in this study is the rate of successful dural puncture at the first attempt. It was assumed that ultrasound could facilitate neuraxial blockade in grade 3 morbidly obese pregnant women according to the Who classification, whose topographic anatomy is difficult.

Spinal anesthesia is the most commonly used anesthesia method for elective cesarean deliveries. Anesthesiologists may have difficulties in determining the poorly palpable surface landmarks in morbidly obese pregnant women. Manual palpation technique, which is preferred in neuraxial anesthesia, may be difficult in obese pregnant women due to the difficulty in identifying bone landmarks. Neuraxial ultrasound examination before spinal anesthesia may help spinal anesthesia performance and decrease number of attempts in obese parturients. This study will be conducted as a single-center, prospective, randomized, double-blinded trial in a university hospital. Patients scheduled for elective cesarean will be screened for enrollment in the study. Patient, the anesthetist administering spinal anesthesia and evaluating the data were blind to the distribution of patient groups.Ultrasonographic examinations were performed by a single investigator trained in this technique who performed more than 150 ultrasound-guided neuraxial blocks.

In the operating room, all of the patients will receive standard monitoring. Scans will be made in logiditunal parasagittal and transverse midline views with ultrasound. Needle entry sites in the L2-L3 and L3-L4 intervals will be determined as the intersection of the longiditunal and transverse lines. When the spinal puncture operator is outside the room, Needle entry sites were marked for both groups.After skin marking, the pregnant woman will be asked to remain still and a subarachnoid puncture will be performed immediately. Spinal anesthesia will be administered with injection of intrathecal bupivacaine.

In the Landmark group, the injection site will be determined using the traditional method of palpating the posterior superior iliac spine.When the spinal puncture operator is outside the room, Needle entry sites were marked for both groups.After skin marking, the pregnant woman will be asked to remain still and a subarachnoid puncture will be performed immediately. Spinal anesthesia will be administered with injection of intrathecal bupivacaine.

Success on a single-puncture attempt will be defined as reaching the subarachnoid space on the first insertion of the needle.

The duration from initiation of location marking by palpation or ultrasound to obtaining free cerebrospinal fluid flow

Time interval between the operator touches the parturient and the completion of the needle insertion point marking

The time interval between the needle insertion to visualization of cerebrospinal spinal fluid in the spinal needle.

Patients rated their satisfaction as very satisfied, satisfied, or dissatisfied immediately after the procedure.

Inclusion Criteria: Parturient who will receive selective cesarean delivery under spinal anesthesia ASA 2-3 scheduled for elective sections BMI≥40 kg/m2 normal singleton pregnancy ≥37 weeks of gestation Exclusion Criteria: Multiple gestations Emergency C-section exist contraindications of spinal anesthesia Local anesthetics allergy BMI<40 kg/m2 history of lumbar spinal diseases and lumbar surgery Parturient refusal