A Real-Time Ultrasound Guided Approach For Spinal Anesthesia

Not Applicable

Completed

Interventions: Other: standard spinal anesthesia
Other: ultrasound-guided spinal anesthesia

Brief Summary: 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.

Detailed Description: 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.

Recruitment & Eligibility

Inclusion Criteria

Exclusion criterion:

1 Patients who have undergone previous Spine Surgery

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
standard spinal anesthesia	standard spinal anesthesia	randomized participants will be given standard spinal anesthesia insertion technique for block placement by Anesthesiologist
ultrasound-guided spinal anesthesia	ultrasound-guided spinal anesthesia	participants will randomly assigned to use ultrasound-guided technique for block placement by Anesthesiologist.

Primary Outcome Measures

Name	Time	Method
Number of Attempts	10-15 minutes before the surgery	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

Secondary Outcome Measures

Name	Time	Method
Time to Perform Block (Second)	as measured in seconds after needle insertion, surgical date	Time to perform block (from first needle insertion to injection of medication)
Difficulty of Block Insertion	10-15 minutes before the surgery	Difficulty of insertion, was rated by the performing anesthesiologist on a 10-point Likert scale from one (easy) to ten (extremely difficult)
Patient Satisfaction	after insert the block but before the surgery	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.