Evaluation of the effect of 0.2 ml of cerebro-spinal fluid aspiration at the end of intrathecal injection of bupivacaine 0.5% on the onset time and sensory block level in cesarean section under spinal anesthesia.

Determination of the effect of 0.2 ml of cerebrospinal fluid aspiration at the end of intrathecal injection of bupivacaine 0.5% on the onset time and sensory level in cesarean section under spinal anesthesia.

This clinical trial with a control group with parallel, double-blind, randomized, phase 2-3 groups was performed on 60 patients and randomization block was used for randomization.

At the end of the drug injection in spinal anesthesia, in 30pregnant patients in group A (aspiration group), 0.2 ml of CSF is re-aspirated and re-injected into the subarachnoid space and in 30 pregnant patients in group B (without aspiration), without CSF aspiration, the spinal needle is removed and the patient is placed in a supine position.Then the time to reach the maximum level of sensory block (using pinprick), the quality of sensory and motor block (using VAS and bromage score), blood pressure and heart rate at specific times (by non-invasive monitoring of Saadat Model 162 made in Iran) are measured and recorded in a questionnaire.

Inclusion criteria: Conscious consent to participate in the study; 18 to 46 years old; Term pregnancy (37 weeks and more); Candidate for cesarean section under spinal anesthesia; Exclusion criteria: Cancel the continuation of the plan; ‌ Heart and lung diseases, hypertension, diabetes, arrhythmia and heart failure; Multiple pregnancies; Eclampsia and preeclampsia; Contraindications of spinal anesthesia; Emergency C/S

Patients after spinal anesthesia are randomly assigned to one of the two groups of cerebrospinal fluid aspiration ( Intervension group) and without cerebrospinal fluid aspiration (Control group).

Time to reach the maximum sensory block and quality of sensory-motor block

In this study, we will use the quadruple Block Randomization method. For this purpose, we prepare four sheets of paper.Write the letter A on two sheets and the letter B on the other two sheets. Mix the sheets together and place them in the desk drawer. With the referral of each eligible patient, one of the sheets is randomly taken out and based on this sheet is A or B, it will be assigned to one of the two groups of aspiration and non-aspiration. After randomly pulling out all four sheets, all the papers are returned to the drawer and the above procedure will be continued for the next four patients until the desired sample size is reached.

The patients are placed under spinal anesthesia by an anesthesiologist in a sitting position and based on randomization , the patients undergoing aspiration or non-aspiration of cerebro-spinal fluid at the end of spinal anesthesia and then the vital signs, the level and quality of sensory and motor blocks were measured and recorded by Pinprick, VAS and bromage score by the researcher (intern) who has no information on randomization .