None listed
Conditions
Brief summary
It is possible to evaluate the activity of sympathetic nervous system during central neuraxial blocks by analyzing the curve of the finger photoplethysmography. By using finger photoplethysmography as a surrogate method for evaluation of sympathetic nervous system activity, it is possible to compare and quantify the potential difference in the degree of sympathectomy between 0.125% levobupivacaine and 0.125% ropivacaine during epidural analgesia for vaginal delivery. Finger photoplethysmography is also a potential method for early detection of complications that occur as a consequence of sympathectomy (maternal hypotension, fetal bradicardia and eventually emergent cesarean section) When taking into consideration that ropivacine has a lower potential of cardiovascular toxicity compared to levobupivacaine, we hypothesised that ropivacaine, during epidural analgesia for vaginal delivery, also causes a lower level of sympathectomy than levobupivacaine,
Interventions
Before administration of epidural analgesia, all of the patients will be given a prehydration consisting of 1000 ml Ringer's lactate solution intravenously.
Before administration of epidural analgesia, a non-invasive finger photoplethysmography probe will be placed around the first toe of the left leg, as well as the 3 ECG electrodes which will be placed on the chest and a cuff of the mercury sphygmomanometer which will be placed around the left upper arm.
Every measurement of the finger photo
Before administration of epidural analgesia, all of the patients will be given a prehydration consisting of 1000 ml Ringer's lactate solution intravenously. Before administration of epidural analgesia, a non-invasive finger photoplethysmography probe will be placed around the first toe of the left leg, as well as the 3 ECG electrodes which will be placed on the chest and a cuff of the mercury sphygmomanometer which will be placed around the left upper arm. Every measurement of the finger photoplethysmography signal (measured simultaneously with the ECG) will be recorded between the contractions during labour, in a sequence of 30 seconds and will be automatically storaged in the BIOPAC SS4LA software. The mentioned finger photoplethysmography software enables re-run of every single measurement to extract certain parameters (area under the curve, amplitude and the pulse transit time) from the finger photoplethysmography curve. Epidural space will be identified in the L3-4 interspace by the loss of resistance technique, using 17 G Tuohy needle, in the lying or left lateral position of the patient. After identification of epidural space, epidural cathether will be inserted 4-5 cm into the epidural space. After the aspiration test and administration of a test dose (3 ml of 2% lidocaine), the patients will be given a bolus dose of epidural analgesia, in the lying position with slightly (up to 30 degrees) elevated head of the bed. The patients will be randomised by the type of the local anesthetic solution given into the epidural space: group 1 will be given 10 ml of 0.125% ropivacaine + 100 mcg of fentanyl and group 2 will be given 10 ml of 0.125% levobupivacaine + 100 mcg of fentanyl. Dose, volume and concentrations of two local anesthetics are the same in both groups, as well as the dose of the opioid added in the mixture. The bolus dose of epidural will be applied in the following manner: first 5 ml of the local anesthetic/opiod solution will be given as a bolus, and the rest of the solution (5 ml) will be given after 3-4 minutes, also as a bolus. The described procedure is a standarised protocol for painless vaginal delivery used at our institution. The study will be conducted in the labour ward, with a controlled ambient temperature of 24 degrees celsius.
Sponsors
Clinic for Obstetrics and Gynecology; University Clinical Hospital Center Zagreb
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
The study will include all of the patients in whom lumbar epidural analgesia, as a standard method for painless vaginal delivery, is indicated.
Exclusion criteria
Any kind of hypertensive disorder. Vasoactive drug therapy. Obesity (BMI>30) Peripheral blood vessel disease (deep venous thrombosis, Raynaud's syndrome) Failed epidural analgesia. Uncooperation (movement of the legs during recording of the finger photoplethysmography signal)
Outcome results
None listed