Changes in the Microvascular Reactivity on Leg During Spinal Anesthesia

Pusan National University Hospital51 enrolled

Overview

Anesthesia alters microcirculation and tissue oxygen saturation (StO2). We sought to examine changes in StO2 using near-infrared spectroscopy and a vascular occlusion test (VOT) during spinal anesthesia. This prospective observational study was included 51 patients without comorbidities who underwent elective surgery under spinal anesthesia. We measured the StO2 in the lower extremity during VOT before and after intrathecal injection.

The vascular occlusion test (VOT) procedure was conducted twice in each patient, before and 15 min after intrathecal injection. An near-infrared spectroscopy (NIRS) sensor (INVOSTM 5100C Cerebral/Somatic Oximeter; Medtronic, Minneapolis, MN, USA) was attached to the patient's gastrocnemius muscle. A tourniquet (A.T.S ® 3000 Automatic Tourniquet System; Zimmer Inc., Warsaw, IL, USA) was applied to the thigh and inflated to a pressure value 50 mmHg over the patient's baseline systolic blood pressure in the leg and maintained for 5 min. After a 5-min ischemic period, the tourniquet was rapidly deflated to 0 mmHg. The tissue oxygen saturation (StO2) data was continuously recorded during the VOT procedure. After confirmation of spinal anesthesia using cold sensitivity, the VOT procedure was repeated in the same manner as mentioned above. The occlusion slope and recovery slope were calculated based on the measured StO2 data. The occlusion slope was defined as the descending slope of StO2 value until it reached the minimum value. The recovery slope was calculated from the deflation of the tourniquet until the recovery of StO2 to the maximum value.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Spinal Anesthesia

Interventions

Vascular occlusion testDIAGNOSTIC_TEST

The VOT procedure was conducted twice in each patient, before and 15 min after intrathecal injection. An NIRS sensor (INVOSTM 5100C Cerebral/Somatic Oximeter; Medtronic, Minneapolis, MN, USA) was attached to the patient's gastrocnemius muscle. A tourniquet (A.T.S ® 3000 Automatic Tourniquet System; Zimmer Inc., Warsaw, IL, USA) was applied to the thigh and inflated to a pressure value 50 mmHg over the patient's baseline systolic blood pressure in the leg and maintained for 5 min. After a 5-min ischemic period, the tourniquet was rapidly deflated to 0 mmHg. The StO2 data was continuously recorded during the VOT procedure. After confirmation of spinal anesthesia using cold sensitivity, the VOT procedure was repeated in the same manner as mentioned above. The occlusion slope and recovery slope were calculated based on the measured StO2 data.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 60 Years

Medical Language ↔ Plain English

Inclusion Criteria: * The patients who were scheduled for spinal anesthesia * 18\< age \< 60 years old Exclusion Criteria: * American Society of Anesthesiologists physical status class \> III, * allergy or sensitivity to study medications, * alcohol or drug abuse history, * body mass index \> 35 kg/ m2 or \< 15 kg/m2, * p regnancy or breastfeeding status, * diabetes and on insulin treatment, * untreated or uncontrolled arterial hypertension, * peripheral arterial disease, * corticosteroid treatment, coagulopathy, and lower limb deformities or burns * patients who may not tolerate VOT

Locations (1)

Pusan National University Hopsital

Busan, South Korea

Outcomes

Primary Outcomes

Change of recovery slope between baseline and after spinal anesthesia

Recovery slope is related to microvascular reactivity, was calculated from the deflation of the tourniquet until the recovery of tissue oxygen saturation to the highest value

Time frame: baseline and immediately after spinal anesthesia

Data from ClinicalTrials.gov

This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.