Spinal Anesthesia
Conditions
Keywords
Microvascular Circulation, Spectroscopy, near-infrared, Spinal anesthesia
Brief summary
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.
Detailed description
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.
Interventions
DIAGNOSTIC_TESTVascular occlusion 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.
Sponsors
Pusan National University Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of recovery slope between baseline and after spinal anesthesia | baseline and immediately 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 |
Countries
South Korea
Outcome results
None listed