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

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.

Conditions

• Initial Systolic Blood Pressure (mmHg)
• Arterial Occlusion Pressure (mmHg)
• Tourniquet Time (Minutes)
• Quality of Bloodless Surgical Field (4 Point Scale)
• Initial Tourniquet Pressure (mmHg)
• Maximal Systolic Blood Pressure (mmHg)
• Maximal Tourniquet Pressure (mmHg)

Interventions

PROCEDURE

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 a pneumatic tourniquet. The cuff (11 cm) of the tourniquet will be placed around the arm with the distal edge 5 cm above the olecranon. AOP estimation formula according to initial systolic blood pressure (SBP) and Tissue Padding Coefficient (KTP) values (AOP= \[SBP+10\]/KTP) from a list (Table 1) will be used to calculate AOP (17). After calculation of AOP, a safety margin of 20 mmHg will be added to AOP to determine the TP (TP=AOP+20 mm Hg). Exsanguination of the limb will be provided with an Esmarch bandage and the cuff will be inflated to the predetermined TP. TP will be manually raised in response to each 10 mmHg increase in SBP during the surgical procedure.

Sponsors & Collaborators

• Baskent University Ankara Hospital

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-10-08

Primary Completion

2021-01-09

Completion

2021-01-09

Countries

• Turkey (Türkiye)

Study Locations