Does Anesthetic Technique Affect Pneumatic Tourniquet Pressures in Upper Limb Fracture Surgery?

Not Applicable

Completed

• Conditions: Tourniquet Time (Minutes); Initial Tourniquet Pressure (mmHg); Initial Systolic Blood Pressure (mmHg); Quality of Bloodless Surgical Field (4 Point Scale); Maximal Tourniquet Pressure (mmHg); Arterial Occlusion Pressure (mmHg); Maximal Systolic Blood Pressure (mmHg)
• Interventions: Procedure: Upper limb fracture surgery and arterial occlusion pressure (AOP) estimation based tourniquet pressure (TP) setting

• Registration Number: NCT04710225
• Lead Sponsor: Baskent University Ankara Hospital

Brief Summary

In pneumatic tourniquet applications, the use of an individualized, lowest-effective tourniquet pressure (TP) has been recommended, in order to avoid pressure related complications. The aim of this study is to compare the effects of general anesthesia and axillary block on arterial occlusion pressure (AOP) estimation based TP settings in upper limb fracture surgery.

After, ethical committee approval 80 adult patients undergoing upper limb fracture surgery who gave their signed informed consent will be included. The age below 18 and above 85 years, American Society of Anesthesiology (ASA) physical status \>2, any contraindication to axillary block or GA, adverse reaction history to anesthetic drugs, severe anemia, and refusal to give informed consent will be the exclusion criteria. The patients will be randomized to one of two study groups using a computer-generated randomization list to receive GA (Group 1) and axillary block (Group 2).

Main endpoints are initial and maximal blood pressures, AOP, initial and maximal TPs, and tourniquet time. Additionally, the surgeon will evaluate the quality of bloodless surgical area with respect to the amount of blood using a 4-point scale (1: Excellent= No blood in the surgical field, 2: Good= Some blood in the surgical field but no interference with surgery, 3: Fair= Blood in the surgical field but no significant interference with surgery, 4: Poor= Blood in the surgical field obscures the view) at the beginning, in the middle, and at the end of the surgical procedure. The patients will be observed for signs of tourniquet related complications by a blind investigator. SPSS 20.0 for Windows is used for data analysis. The t test and the χ2 test will be used for continuous and categorical data respectively. A P value below 0.05 will be considered as statistically significant.

Detailed Description

Not available

Study Timeline

• Study Start: 2019-10-08
• Status Verified: 2021-01
• Primary Completion: 2021-01-09
• Study Completion: 2021-01-09
• Study First Submitted: 2021-01-10
• Study First Submitted QC: 2021-01-13
• Last Update Submitted: 2021-01-13
• Study First Posted: 2021-01-14
• Last Update Posted: 2021-01-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 69

Inclusion Criteria

• Adult patients undergoing upper limb fracture surgery

Exclusion Criteria

• The age below 18 and above 85 years,
• American Society of Anesthesiology (ASA) physical status >2
• Any contraindication to axillary block or general anesthesia
• Any contraindication to tourniquet use
• Adverse reaction history to anesthetic drugs
• Severe anemia
• Refusal to give informed consent

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Group 2 (Multiple injection axillary block group)	Upper limb fracture surgery and arterial occlusion pressure (AOP) estimation based tourniquet pressure (TP) setting	Multiple injection axillary block will be performed with the aid of a nerve stimulator. When the slight twitching of the motor response from the relevant muscles is achieved (at 0.4 mA, 2Hz, 0.1 ms) % 18-20 ml of Bupivacaine 0.5 (90-100 mg) will be injected.
Group 1 (General anesthesia group)	Upper limb fracture surgery and arterial occlusion pressure (AOP) estimation based tourniquet pressure (TP) setting	Upper limb fracture surgery will be performed with the aid of pneumatic tourniquet. General anesthesia will be induced with intravenous (IV) thiopental sodium and fentanyl. Rocuronium will be used as the neuromuscular blocking agent. Endotracheal tube will be placed and anesthesia will be maintained with sevoflurane and IV fentanyl while the lungs were ventilated with O2-N2O (50-50%) to achieve an EtCO2 at 30-35 mm Hg.

Primary Outcome Measures

Name	Time	Method
Initial and maximal tourniquet pressures (mmHg)	Intraoperative	Initial and maximal tourniquet pressures define first adjusted and maximal tourniquet pressures during surgery.
Tourniquet time (minute)	Intraoperative	Tourniquet time defines the time period between the inflation and deflation of the tourniquet cuff at the beginning and end of the surgery respectively.
Initial and maximal systolic blood pressure (mmHg)	Intraoperative	Initial and maximal systolic blood pressures define the systolic blood pressures measured and recorded by the patient monitor just before tourniquet inflation and during tourniquet application respectively.
Arterial occlusion pressure (mmHg)	Intraoperative	Arterial occlusion pressure is the minimal tourniquet pressure required to cease arterial blood flow to the limb and calculated with AOP estimation formula according to initial SBP and Tissue Padding Coefficient (KTP) values (AOP= \[SBP+10\]/KTP) from a list.

Secondary Outcome Measures

Name	Time	Method
The quality of bloodless surgical area	Intraoperative	The quality of bloodless surgical area will be evaluated by the surgeon respect to the amount of blood using a 4-point scale (1: Excellent= No blood in the surgical field, 2: Good= Some blood in the surgical field but no interference with surgery, 3: Fair= Blood in the surgical field but no significant interference with surgery, 4: Poor= Blood in the surgical field obscures the view) at the beginning, in the middle, and at the end of the surgical procedure.

Trial Locations

Locations (1)

Baskent University; 🇹🇷 Ankara, Turkey