Evaluation of Lumbar Plexus Block Success With Near Infrared Spectroscopy (NIRS)

Study Overview
=================
Brief Summary
-----------------
Tests such as the pin-prick test, cold application or the Bromage scale are currently used to measure the success of nerve blocks and are considered subjective assessments as they require verbal consent from the patient. Near Infrared Spectroscopy (NIRS) measures the differential absorption and reflection of near infrared light transmitted by human tissues, providing a tissue-oxygen saturation index. Modern NIRS-based instruments use multiple detectors to filter spectroscopy data from skin structures to detect subcutaneous tissue oxygenation. Successful regional anesthesia results in decreased sympathetic activity within the distribution of blocked nerves. Regional oxygen saturation (rSO2) has been shown to increase in innervated areas after sympathetic block.

Detailed Description
-----------------
The aim of this study was to show whether the success of lumbar plexus block applied in lower extremity orthopedic surgeries can be evaluated by Near Infrared Spectroscopy (NIRS), which is used to measure tissue oxygenation.

Official Title
-----------------
Near Infrared Spectroscopy (NIRS) Evaluation of Lumbar Plexus Block Success for Lower Extremity Orthopedic Surgery

Conditions
-----------------
Nerve Block, Lumbar Plexus, Near Infrared Spectroscopy

Intervention / Treatment
-----------------
* Device: Near Infrared Spectroscopy


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: 18-90 years old femoral neck fracture, femoral shaft fracture, hip replacement surgery who will undergo velumbar plexus block will be included in the study. Exclusion Criteria: BMI>40 kg/m2 infection in the block area peripheral neuropathy, hemoglobinopathy peripheral vascular disease allergy to local anesthetics patients with contraindications for lumbar plexus block

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Near İnfrared Spektroskopi (NIRS)<br>Peripheral oxygen saturation to be measured with NIRS device | Device: Near Infrared Spectroscopy<br>* Two NIRS probes will be attached to the extremity to be operated on and to the other lower extremity on the opposite side, at a level approximately coinciding with the midline above the quandriceps femoris muscle.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| rso2 | The regional oxymetry probe will be placed in the the quandriceps femoris muscle, one on the extremity to be operated on and the other on the opposite lower extremity. | 40 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sensory block level | The sensory block level will be realised by cold testing at 10 minute intervals after applying the block. | 40 minutes | 
| blood pressure values | systolic, diastolic and mean blood pressure values will be recorded non-invasively in mmhg. | 40 minutes | 
| so2 | fingertip SO2 measured by pulse oximetry | 40 minutes |