A Real-Time Ultrasound Guided Approach For Spinal Anesthesia

Our goal was to compare the number of attempts to perform spinal anesthesia using real-time ultrasound guidance versus landmark technique in patients meeting predefined criteria for difficult spinal anesthesia.

Patients who consent to receive spinal anesthesia (as opposed to some other anesthetic technique) and who meet the inclusion/exclusion criteria for the study (given below) will be randomized on day of surgery after obtaining informed consent to either ultrasound-guided or standard spinal anesthesia technique. A block randomization scheme with random block sizes ranging from 2-8 patients will be used. The outcomes will be recorded by a third party observer in the block room/operating room who might be a nurse or resident or clinical research fellow not directly involved with performing the block. The post procedure outcomes will also be recorded by a clinical research fellow or resident who was not directly involved with performing the block. No sample size estimation methodology currently exists for the right-censored count data models. We expect less number of attempts in the ultrasound group a 20 % difference between the two groups which we feel is a minimum of a clinically-relevant effect. At the 0.05 level of significance with a power of 0.8, we will require a minimum of 20 patients per group,therefore we plan to recruit 40 patients in total. The analysis will be conducted by a statistician who will be blinded.

participants will randomly assigned to use ultrasound-guided technique for block placement by Anesthesiologist.

randomized participants will be given standard spinal anesthesia insertion technique for block placement by Anesthesiologist

Number of attempts (defined as number of needle reinsertions form the skin and NOT number of redirection of the needle) at the beginning of surgery

Difficulty of insertion, was rated by the performing anesthesiologist on a 10-point Likert scale from one (easy) to ten (extremely difficult)

Record patient satisfaction on a five-point Likert scale, where a value of 1 indicates extremely unsatisfied and a value of 5 indicates extremely satisfied.

Inclusion Criteria: Patients aged 55 or older BMI more than 40 Scoliosis Exclusion criterion: 1 Patients who have undergone previous Spine Surgery