Measurement of Hemodynamic Variables Under Spinal Anesthesia With Varied Positioning

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.

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.)