Anesthesia, Pregnancy
Conditions
Brief summary
Multiple studies have compared spinal anesthetic performed supine versus lateral, with varying results, in parturients having elective cesarean section. Needle positioning during spinal placement has also been examined. No positioning techniques have demonstrated definitive superiority for hemodynamic stability. Investigators propose that following spinal placement in the sitting position if the patient is placed in a lateral position for 90 seconds prior to turning them supine, hemodynamic changes caused by sympathectomy related to the subarachnoid block can be avoided. This is the first study to examining the influence of position changes after spinal anesthetic placement in the sitting position, which includes hemodynamic variables not previously studied including cardiac output, TPR (total peripheral resistance) and pulse pressure variation (PPV).
Detailed description
Cesarean section is chosen when natural spontaneous vaginal delivery is either not possible or when the health of the baby or mother is compromised. Cesarean section may be planned, urgent, or performed emergently when the life of the baby or mother is threatened. Cesarean section is performed using different anesthetic techniques including: spinal, epidural, combined spinal and epidural, and general anesthesia. Spinal anesthesia is the most common technique chosen due to its relative safety, rapid onset and avoidance of potential complications from general anesthesia. It is the technique of choice for elective cesarean section unless contraindicated. Spinal anesthesia causes sympathetic blockade followed by sensory and motor blockade. Nerve fiber size explains the speed of onset and differential block. The critical moments during spinal anesthesia come as soon as local anesthetic is injected into the subarachnoid space.
Interventions
OTHERSupine position
Spinal anesthesia in sitting position then 2 minutes in Supine position after spinal anesthetic administration
Spinal anesthesia in sitting position then 2 minutes in the right lateral position after spinal anesthetic administration
Spinal anesthesia in sitting position then 2 minutes in the left lateral position after spinal anesthetic administration
Sponsors
The University of Texas Medical Branch, Galveston
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Parturients undergoing elective cesarean section under spinal anesthesia * Singleton intrauterine pregnancy with appropriate gestational age fetus (AGA) at gestational age 37 to 42 weeks
Exclusion criteria
* Large for gestational age, small for gestational age, and multiple gestations * Patients with cardiovascular disease like hypertension, etc. * Non-English or non-Spanish speakers * BMI \>40 * Inadequate or failed blocks and inadvertently high levels of spinal blockade will be dropped from the study * Incarcerated parturients * Expected heavy bleeding (placenta accreta, vascular anomaly, etc.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate | Immediately before spinal anesthestic placement through placental delivery | Continuous Heart rate (beats per minute) measurements. |
| Blood pressure | Immediately before spinal anesthetic placement through placental delivery | Continuous Blood pressure (mmHg) measurements |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of vasopressor usage | Spinal anesthetic placement through placental delivery | Number of vasopressor use events will be monitored and recorded. |
| Total vasopressor usage | Spinal anesthetic placement through placental delivery | All vasopressor administrations with time stamps will be documented. |
| Incidence of nausea and vomiting | Number of events spinal anesthetic placement through placental delivery | Nausea and vomiting incidence and anti-emetic administration with time stamps will be documented. |
| Non Invasive Cardiovascular measurements: stroke volume | Spinal anesthetic placement through placental delivery | Continuous Stroke volume (mL) measurements |
| Non Invasive Cardiovascular measurements: TPR (total peripheral resistance) | Spinal anesthetic placement through placental delivery | Continuous TPR (total peripheral resistance, dynes\*sec/cm3)measurements |
| Non Invasive Cardiovascular measurements: cardiac output | Spinal anesthetic placement through placental delivery | Continuous Cardiac output (L/min) measurements |
| Anti-emetic medication | Number of events spinal anesthetic placement through placental delivery | Anti-emetic administration with time stamps will be documented. |
Countries
United States
Outcome results
None listed