Effect of Tourniquet Use on Muscle Thigh Function.

University of Chile30 enrolled

Overview

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.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

SINGLE

Enrollment

Conditions

Pneumatic Tourniquet Muscle Weakness

Interventions

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Postoperative muscle dysfunction

Fall greater or equal than 10% of the voluntary isometric muscle contraction from basal

Time frame: 24 hours

Secondary Outcomes

Basal upper and lower extremity blood pressures

Pre spinal anesthesia measured blood pressures

Time frame: Up to 2 hours pre spinal anesthesia

Upper and lower extremity blood pressures after spinal anesthesia

Post spinal anesthesia measured blood pressures

Time frame: 10 minutes after spinal anesthesia

Arterial occlusion pressure

Doppler estimation of arterial occlusion pressure of the lower extremity surgical side

Time frame: 10 minutes after spinal anesthesia

Pneumatic tourniquet inflation pressure

Arterial occlusion pressure plus a safety margin

Time frame: 3 hours from tourniquet inflation

Pneumatic tourniquet inflation time

Time from inflation to release of the pneumatic tourniquet

Time frame: 3 hours from tourniquet inflation

Quadriceps electromyographic activation profile

Basal and 24 hours (post surgery) quadriceps activation on surgical side

Time frame: 24 hours

Quadriceps muscle tone

Basal and 24 hours (post surgery) measurement of quadriceps muscle tone on surgical side

Time frame: 24 hours

Thigh perimeter

Basal and 24 hours (post surgery) bilateral measurement of thigh perimeter

Time frame: 24 hours

Thigh pain

Basal and 24 hours (post surgery) bilateral thigh pain measured with a numerical rating scale (0-10)

Time frame: 24 hours

Postoperative measurements time

Time from pneumatic tourniquet release to postoperative muscle function measurements

Time frame: 24 hours

Effect of Tourniquet Use on Muscle Thigh Function.

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts