Comparison of Successful Spinal Needle Placement Between Crossed Leg Sitting Position and Traditional Sitting Position

Approval from Ethical Committee of Faculty of Medicine Universitas Indonesia was acquired prior conducting the study. Subjects were given informed consent before enrolling the study. Subjects were randomly divided into CLSP Group for crossed leg sitting position (n=105) and TSP Group for traditional sitting position (n=106). Non-invasive blood pressure (NIBP) monitor, eletrocardiography (ECG), oxygen nasal cannula and pulse-oxymetry was set on the subjects in the operation room. Baseline information was recorded. Spinal anesthesia was done by anesthesiology registrars that have done 50 spinal anesthesia procedures and have been explained about the protocol of spinal anesthesia injection in this study (to avoid bias). Outcome measures were the number of successful spinal needle placement in the first attempt, the difficulty level of landmark palpation for injection, and the number of needle-bone contact. Data was analyzed by SPSS (Statistical Package for Social Scientist) using Chi-Square test, Fisher Exact test, and Kolmogorov-Smirnov test. Significance value used was 5% with 80% power.

Inclusion criteria

• subjects aged 18-60 years old-
• subjects with ASA physical status I-III who were planned to undergo urology surgery with spinal anesthesia
• Subjects who have been explained about the study, have agreed to enroll and have signed the informed consent form

Exclusion criteria

• uncooperative subjects
• subjects with relative and absolute contraindications to spinal anesthesia (coagulation disorders, thrombocytopenia, increases intracranial pressure, severe hypovolemia, severe heart valve disorders, local infection at the injection site, allergy toward local anesthetic agents, significant anatomical disorder of the spine, wound/scar on the lumbal area)
• subjects with body mass index (BMI) > 32 kg/m2

Drop out criteria:

• subjects who requestes to drop out of the study
• subjects in need of emergency treatment during spinal anesthesia procedure
• subjects with more than nine times redirected spinal needle (failed spinal anesthesia procedure).