BMI More Than 40 kg/m2, Patients Aged 55 or Older, Scoliosis
Conditions
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.
Interventions
ultrasound-guided technique for block placement
OTHERstandard spinal anesthesia
Anesthesiologist will use standard technique for placement of spinal block.
Sponsors
The Cleveland Clinic
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
55 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Patients aged 55 or older 2. BMI more than 40 3. Scoliosis Exclusion criterion: 1 Patients who have undergone previous Spine Surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| 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) |
Countries
United States
Participant flow
Recruitment details
patients were recruited and enrolled from 4/2012 to 10/2012 at Cleveland clinic, main campus.
Participants by arm
| Arm | Count |
|---|---|
| Ultrasound-guided Spinal Anesthesia Anesthesiologist will use ultrasound-guided technique for spinal anesthesia block placement.
ultrasound guided placement spinal block: Anesthesiologist will use ultrasound as a guide for placement of spinal block. | 14 |
| Standard Spinal Anesthesia Anesthesiologist will use standard spinal anesthesia insertion technique for block placement.
standard spinal anesthesia: Anesthesiologist will use standard technique for placement of spinal block. | 18 |
| Total | 32 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 3 | 1 |
| Overall Study | treatment: not given or discontinued | 2 | 0 |
Baseline characteristics
| Characteristic | Ultrasound-guided Spinal Anesthesia | Standard Spinal Anesthesia | Total |
|---|---|---|---|
| Age, Continuous | 69 years STANDARD_DEVIATION 10 | 70 years STANDARD_DEVIATION 10 | 70 years STANDARD_DEVIATION 10 |
| Sex: Female, Male Female | 10 Participants | 9 Participants | 19 Participants |
| Sex: Female, Male Male | 4 Participants | 9 Participants | 13 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 14 | 0 / 18 |
| other Total, other adverse events | 0 / 14 | 0 / 18 |
| serious Total, serious adverse events | 0 / 14 | 0 / 18 |
Outcome results
Primary
Number of Attempts
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
Time frame: 10-15 minutes before the surgery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Ultrasound-guided Spinal Anesthesia | Number of Attempts | 1 Attempts |
| Standard Spinal Anesthesia | Number of Attempts | 1 Attempts |
Comparison: We hypothesized that real-time US guidance would result in a 20% lower number of attempts compared to the control group.~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 planned to recruit 40 patients in total.p-value: 0.83Kruskal-Wallis
Secondary
Difficulty of Block Insertion
Difficulty of insertion, was rated by the performing anesthesiologist on a 10-point Likert scale from one (easy) to ten (extremely difficult)
Time frame: 10-15 minutes before the surgery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Ultrasound-guided Spinal Anesthesia | Difficulty of Block Insertion | 5.5 units on a scale |
| Standard Spinal Anesthesia | Difficulty of Block Insertion | 2.5 units on a scale |
p-value: 0.001Kruskal-Wallis
Secondary
Patient Satisfaction
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.
Time frame: after insert the block but before the surgery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Ultrasound-guided Spinal Anesthesia | Patient Satisfaction | 5 units on a scale |
| Standard Spinal Anesthesia | Patient Satisfaction | 5 units on a scale |
p-value: 0.09Kruskal-Wallis
Secondary
Time to Perform Block (Second)
Time to perform block (from first needle insertion to injection of medication)
Time frame: as measured in seconds after needle insertion, surgical date
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Ultrasound-guided Spinal Anesthesia | Time to Perform Block (Second) | 117.5 second |
| Standard Spinal Anesthesia | Time to Perform Block (Second) | 256 second |
p-value: 0.06Kruskal-Wallis