Ankle Fusion, Intraoperative Hypertension, Total Ankle Arthroplasty, Tourniquet Hypertension
Conditions
Keywords
Perifemoral, Tourniquet, Mepivacaine, Tourniquet Hypertension
Brief summary
The purpose of this prospective randomized double-blind study is to determine if the novel technique of ultrasound guided peri-arterial injection of local anesthetic around the femoral artery decreases ischemic hypertension associated with prolonged lower extremity tourniquet time during total ankle arthroplasty (TAA) and foot fusion surgeries. Patients will be randomized 1:1 to receive either local anesthetic or saline, which will be injected superomedially to the femoral artery in an attempt to block sympathetic afferents and decrease tourniquet associated hypertension intraoperatively.
Detailed description
The purpose of this prospective randomized double-blind study is to determine if the novel technique of ultrasound guided peri-arterial injection of local anesthetic around the femoral artery decreases ischemic hypertension associated with prolonged lower extremity tourniquet time during total ankle arthroplasty (TAA) and foot fusion surgeries. Efficacy will be determined by analyzing incidence of intraoperative ischemic hypertension, defined as \>30% increase in systolic blood pressure, associated with tourniquet inflation times greater than 90 minutes. The study will involve a total of 30 patients (15 in each group) and with a power of 80% to detect a 50% difference. The patients involved in the study will be ASA 1-3 patients who are undergoing either TAA or foot fusion surgeries. Patients will receive standard of care for their anesthesia, which at Duke Hospital includes placement of popliteal and saphenous perineural catheters and a general anesthetic with a laryngeal mask airway. Patients will be randomized to receive femoral peri-arterial injection with either 1.5% mepivacaine with 1:400,000 epinephrine or 0.9% saline which will be performed preoperatively at time of perineural catheter placement. Patients will assume standard risk associated with nerve blocks, including theoretical risk of nerve damage and local anesthetic systemic toxicity. Possible benefits include improved intraoperative hemodynamic stability, decreased intraoperative opioid and antihypertensive medications, and decreased tourniquet associated pain post-operatively.
Interventions
DRUGMepivacaine
An ultrasound guided injection of mepivacaine superomedially to the femoral artery.
An ultrasound guided injection of mepivacaine superomedially to the formal artery in an effort to numb the nerves that contribute to tourniquet hypertension intraoperatively.
DRUGSaline
An ultrasound guided injection using a medication that does NOT numb any nerves called saline, or salt water.
Sponsors
Duke University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
Patients that will be included in the study are English speaking 18-75 year old ASA 1-3 patients undergoing total ankle arthroplasty.
Exclusion criteria
1. ASA 4 or 5 2. Diagnosis of chronic pain 3. Daily chronic opioid use (over 3 months of continuous opioid use). 4. Inability to communicate pain scores or need for analgesia. 5. Infection at the site of block placement 6. Age under 18 years old or greater than 75 years old 7. Pregnant women (as determined by standard of care day-of surgery urine bHCG) 8. Intolerance/allergy to local anesthetics 9. Weight \<50 kg 10. Suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years. 11. Uncontrolled anxiety, schizophrenia, or other psychiatric disorder that, in the opinion of the investigator, may interfere with study assessments or compliance. 12. Current or historical evidence of any clinically significant disease or condition that, in the opinion of the investigator, may increase the risk of surgery or complicate the subject's postoperative course
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Subjects Experiencing Tourniquet Hypertension | Intraoperatively (~3 hours) | Measuring systolic blood pressure using a cuff, aim to keep \<30mmHg change from baseline |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Scores as Measured by the Numeric Rating Scale (NRS-11) | While in PACU (~1 hour) | The Numeric Rating Scale (NRS-11) is an 11-point scale for patient self-reporting of pain. 0 = No Pain, 1-3 = Mild Pain, 4-6 = Moderate Pain, 7-10 = Severe Pain. |
| Amount of Opioid Pain Medications Used by Patient | Perioperative period (~4 hours) | Amount of opioid pain medication used by patient over a 4 hour period immediately after surgery. Opioids taken are converted to morphine equivalents. |
| Amount of Esmolol Used Intraoperatively | Intraoperatively (~3 hours) | Amount of esmolol (in mg) used intraoperatively to decrease blood pressure after subject achieved tourniquet hypertension. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Mepivacaine Block Group Injection of local anesthetic (mepivacaine) above and beside the femoral artery.
Mepivacaine: An ultrasound guided injection of mepivacaine superomedially to the femoral artery.
Perifemoral Injection of Local Anesthetic: An ultrasound guided injection of mepivacaine superomedially to the formal artery in an effort to numb the nerves that contribute to tourniquet hypertension intraoperatively. | 15 |
| Saline Sham Group Injection of salt water (saline) above and beside the femoral artery.
Perifemoral Injection of Local Anesthetic: An ultrasound guided injection of mepivacaine superomedially to the formal artery in an effort to numb the nerves that contribute to tourniquet hypertension intraoperatively.
Saline: An ultrasound guided injection using a medication that does NOT numb any nerves called saline, or salt water. | 15 |
| Total | 30 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Protocol Violation | 0 | 1 |
Baseline characteristics
| Characteristic | Mepivacaine Block Group | Saline Sham Group | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 10 Participants | 8 Participants | 18 Participants |
| Age, Categorical Between 18 and 65 years | 5 Participants | 7 Participants | 12 Participants |
| Age, Continuous | 60.47 years STANDARD_DEVIATION 11.84 | 65.67 years STANDARD_DEVIATION 4.61 | 63.81 years STANDARD_DEVIATION 9.95 |
| ASA Status ASA 1 | 2 Participants | 0 Participants | 2 Participants |
| ASA Status ASA 2 | 6 Participants | 7 Participants | 13 Participants |
| ASA Status ASA 3 | 7 Participants | 8 Participants | 15 Participants |
| Body Mass Index (BMI) | 31.11 kg/m^2 STANDARD_DEVIATION 4.63 | 32.64 kg/m^2 STANDARD_DEVIATION 5.41 | 31.63 kg/m^2 STANDARD_DEVIATION 5.11 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 14 Participants | 15 Participants | 29 Participants |
| Region of Enrollment United States | 15 Participants | 15 Participants | 30 Participants |
| Sex: Female, Male Female | 2 Participants | 5 Participants | 7 Participants |
| Sex: Female, Male Male | 13 Participants | 10 Participants | 23 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 15 | 0 / 15 |
| other Total, other adverse events | 0 / 15 | 0 / 15 |
| serious Total, serious adverse events | 0 / 15 | 0 / 15 |
Outcome results
Primary
Number of Subjects Experiencing Tourniquet Hypertension
Measuring systolic blood pressure using a cuff, aim to keep \<30mmHg change from baseline
Time frame: Intraoperatively (~3 hours)
Population: Subjects who completed the study.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Mepivacaine Block Group | Number of Subjects Experiencing Tourniquet Hypertension | 5 Participants |
| Saline Sham Group | Number of Subjects Experiencing Tourniquet Hypertension | 14 Participants |
Secondary
Amount of Esmolol Used Intraoperatively
Amount of esmolol (in mg) used intraoperatively to decrease blood pressure after subject achieved tourniquet hypertension.
Time frame: Intraoperatively (~3 hours)
Population: Subjects who completed the study.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Mepivacaine Block Group | Amount of Esmolol Used Intraoperatively | 8.00 mg | Standard Deviation 14.24 |
| Saline Sham Group | Amount of Esmolol Used Intraoperatively | 95.33 mg | Standard Deviation 107.63 |
Comparison: We determined 30 subjects were needed to detect a 50% difference in THN incidence between the two groups using a one-sided Fisher's exact test with alpha = 0.05 and 80% power while allowing up to 20% drop-out. For primary and secondary outcomes, comparisons were made between the two groups using a two-sample t-test or Mann-Whitney U test for continuous variables and Fisher's exact test for categorical variables. p-value of \<0.05 was considered to be statistically significant.p-value: <0.05t-test, 2 sided
Secondary
Amount of Opioid Pain Medications Used by Patient
Amount of opioid pain medication used by patient over a 4 hour period immediately after surgery. Opioids taken are converted to morphine equivalents.
Time frame: Perioperative period (~4 hours)
Population: Subjects who completed the study.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Mepivacaine Block Group | Amount of Opioid Pain Medications Used by Patient | 10.48 morphine equivalents | Standard Deviation 5.77 |
| Saline Sham Group | Amount of Opioid Pain Medications Used by Patient | 8.19 morphine equivalents | Standard Deviation 4.65 |
Secondary
Pain Scores as Measured by the Numeric Rating Scale (NRS-11)
The Numeric Rating Scale (NRS-11) is an 11-point scale for patient self-reporting of pain. 0 = No Pain, 1-3 = Mild Pain, 4-6 = Moderate Pain, 7-10 = Severe Pain.
Time frame: While in PACU (~1 hour)
Population: Subjects who completed the study.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Mepivacaine Block Group | Pain Scores as Measured by the Numeric Rating Scale (NRS-11) | 1.80 score on a scale | Standard Deviation 2.86 |
| Saline Sham Group | Pain Scores as Measured by the Numeric Rating Scale (NRS-11) | 1.07 score on a scale | Standard Deviation 1.71 |