Muscle Weakness, Pneumatic Tourniquet
Conditions
Keywords
Pneumatic Tourniquet, Postoperative Muscle Dysfunction
Brief summary
The use of a pneumatic tourniquet with the purpose of maintaining an operative field free of blood is a common practice in orthopedic surgery. Its use is associated with local and systemic consequences related to hemodynamic and reperfusion ischemia phenomena. Although is known that its use is not an innocuous measure, there is still certain degree blurriness regarding the potential metabolic and functional consequences that may result in the involved limb. In this trial, the investigators are setting out to discriminate the effect of the pneumatic tourniquet on thigh muscle function (strength, tone and activation). The hypothesis is that the pneumatic tourniquet by itself causes a significant postoperative muscular dysfunction of the quadriceps and, thus, the main outcome will be the presence of postoperative quadriceps muscle dysfunction, defined as a fall greater than or equal to 10% of the maximal voluntary isometric contraction measured at 24 hours post surgery.
Interventions
DEVICEPneumatic tourniquet use
Surgery requiring a pneumatic tourniquet on the thigh
Sponsors
University of Chile
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
SINGLE (Outcomes Assessor)
Masking description
Surgical side can not be randomized. Only data assessor will be blinded.
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* Patients undergoing forefoot surgery that requires the use of a pneumatic tourniquet * American Society of Anesthesiologists classification 1-3
Exclusion criteria
* Ambulatory surgery * Adults who are unable to give their own consent * Pre-existing neuropathy or myopathy * Contraindication of tourniquet use * Bilateral surgery * Pregnancy * Hip, thigh, knee, leg or ankle pathologies that prevent or contraindicate using a dynamometer, tonometer or surface electromyographer * Arterial hypertension with systolic pressures above 200mmHg * Renal failure * Hepatic failure
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Postoperative muscle dysfunction | 24 hours | Fall greater or equal than 10% of the voluntary isometric muscle contraction from basal |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Upper and lower extremity blood pressures after spinal anesthesia | 10 minutes after spinal anesthesia | Post spinal anesthesia measured blood pressures |
| Arterial occlusion pressure | 10 minutes after spinal anesthesia | Doppler estimation of arterial occlusion pressure of the lower extremity surgical side |
| Pneumatic tourniquet inflation pressure | 3 hours from tourniquet inflation | Arterial occlusion pressure plus a safety margin |
| Pneumatic tourniquet inflation time | 3 hours from tourniquet inflation | Time from inflation to release of the pneumatic tourniquet |
| Basal upper and lower extremity blood pressures | Up to 2 hours pre spinal anesthesia | Pre spinal anesthesia measured blood pressures |
| Quadriceps muscle tone | 24 hours | Basal and 24 hours (post surgery) measurement of quadriceps muscle tone on surgical side |
| Thigh perimeter | 24 hours | Basal and 24 hours (post surgery) bilateral measurement of thigh perimeter |
| Thigh pain | 24 hours | Basal and 24 hours (post surgery) bilateral thigh pain measured with a numerical rating scale (0-10) |
| Postoperative measurements time | 24 hours | Time from pneumatic tourniquet release to postoperative muscle function measurements |
| Quadriceps electromyographic activation profile | 24 hours | Basal and 24 hours (post surgery) quadriceps activation on surgical side |
Countries
Chile
Contacts
Primary ContactDaniela Bravo, MD
Backup ContactJulian Aliste, MD
Outcome results
None listed