Arterial Occlusion Pressure (mmHg), Initial Systolic Blood Pressure (mmHg), Initial Tourniquet Pressure (mmHg), Maximal Systolic Blood Pressure (mmHg), Maximal Tourniquet Pressure (mmHg), Quality of Bloodless Surgical Field (4 Point Scale), Tourniquet Time (Minutes)
Conditions
Keywords
Pneumatic tourniquet, Pressure, Upper extremity, General anesthesia, Axillary brachial plexus block.
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.
Interventions
PROCEDUREUpper 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
Baskent University Ankara Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 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. |
Countries
Turkey (Türkiye)
Outcome results
None listed