Neuraxial Ultrasound and Combined Spinal-Epidural (CSE) Anesthesia for Cesarean Delivery

Abstract

Neuraxial anesthesia is the gold standard approach for cesarean delivery, offering surgical anesthesia while optimizing maternal and fetal outcomes. This video provides a stepwise demonstration of a combined spinal-epidural (CSE) technique for cesarean delivery. This technique covers patient positioning, identification of the appropriate interspace, sterile preparation, infiltration of local anesthetic, and spinal/epidural needle placement. For single-shot spinal (SSS), a spinal needle is advanced into the subarachnoid space, cerebrospinal fluid return is confirmed with aspiration, and intrathecal medication is administered. For CSE, an epidural needle is advanced into the epidural space using a loss-of-resistance technique, followed by spinal needle insertion through the epidural needle for intrathecal medication administration. This needle-through-needle technique concludes with epidural catheter insertion and securement. Indications and medication dosing for cesarean delivery are discussed for each technique.

Keywords

Neuraxial anesthesia; combined spinal-epidural; spinal anesthesia.

Case Overview

Neuraxial anesthesia is the preferred anesthetic approach for cesarean delivery, providing both surgical and postoperative analgesia while minimizing maternal airway manipulation and side effects of general anesthesia. Cesarean delivery may be performed using a single-shot spinal (SSS), combined spinal-epidural (CSE), or standard epidural technique. The neuraxial technique selected depends on several factors, including delivery urgency, maternal comorbidities, and surgical complexity. Patient preference must also be considered in anesthetic planning.

Neuraxial anesthesia requires careful hemodynamic monitoring during cesarean delivery. Spinal and epidural anesthesia produce anticipated physiologic changes, most notably a sympathectomy-induced vasodilation, which reduces venous return and may precipitate hypotension.¹ Maternal oxygenation, heart rate, and blood pressure should be continuously monitored. Left uterine displacement should be employed to relieve aortocaval compression. Neuraxial-induced hypotension is often managed with prophylactic measures such as crystalloid fluid coloading and a vasopressor infusion.

The most common neuraxial techniques for an elective cesarean delivery are SSS and CSE. SSS anesthesia offers a rapid onset of effective and reliable surgical anesthesia.² The duration of SSS is variable, but reliable surgical anesthesia is generally achieved for around 90 minutes with recommended drugs and dosages (eg, intrathecal hyperbaric bupivacaine 12 mg with fentanyl 15 mcg and morphine 100 mcg).² A CSE offers the same rapid onset of intrathecal anesthesia with the ability to extend anesthesia through the epidural catheter in the event of prolonged surgery or spinal failure. Additionally, the CSE is advantageous for patients with uncertain block spread, such as in early gestation, and in patients who require a reduced initial spinal dose due to underlying comorbidities such as cardiac disease. Current comparative data show no overall superiority of spinal or CSE for scheduled cesarean delivery.³

There are well-documented absolute and relative contraindications to neuraxial anesthesia. Absolute contraindications include patient refusal, infection at the site of injection, elevated intracranial pressure secondary to mass lesion, significant coagulopathy, and uncorrected maternal hypovolemia. Relative contraindications include systemic infection, indeterminate neurological disease, and fixed cardiac output states.^4,5

This video shows a comprehensive step-by-step demonstration of a CSE for cesarean delivery.

The CSE was performed for a repeat cesarean delivery in a patient with a history of early gestation at 32 weeks, body mass index (BMI) 42.1, and two prior cesarean deliveries. Higher BMI and lower gestational age may be associated with more unpredictable intrathecal spread, and morbid obesity with prior surgical history can increase surgical complexity and prolong operative time. Therefore, an epidural catheter was used as an anesthesia backup to allow timely top-up if needed and to avoid conversion to general anesthesia. Patient positioning was optimized, and neuraxial ultrasound was performed. All details regarding the neuraxial ultrasound technique are provided in our previous article.⁶ As preprocedural ultrasound was performed with the patient in the same position as the planned neuraxial technique, routine repalpation was not necessary.

The lumbar region was prepped with aseptic solution. At our institution, we utilize a Perifix FX Epidural kit from B. Braun Medical (Bethlehem, PA, USA). Local anesthetic (1% lidocaine) was infiltrated into the skin. The 17-gauge Tuohy needle was inserted at the L3-L4 interspace. The epidural needle was then advanced through the skin, subcutaneous tissue, supraspinous ligament, and interspinous ligament. Once engaged, the epidural stylet was removed and a loss-of-resistance syringe with saline was attached to the epidural needle. The needle was advanced with continuous pressure on the plunger of the syringe. Upon initial insertion, os was encountered. This is a common occurrence during neuraxial placement. The patient reported sensation of the epidural needle on her right side, and this feedback guided subsequent needle redirection. The stylet was reinserted, and the needle was subsequently redirected to the left. Once re-engaged, the epidural stylet was removed, and the loss-of-resistance syringe was reattached. The needle was again advanced with continuous pressure applied to the plunger of the syringe, with continuous contact with the patient’s back limiting abrupt movement. Once the epidural needle was advanced through the ligamentum flavum, loss of resistance was observed at 7.5 cm. The skin-to-posterior complex depth measured by ultrasound was 6.24 cm; this discrepancy is consistent with the known limitation that ultrasound can underestimate depth of the epidural space in obese patients, and with the need to release probe pressure prior to depth measurement. The syringe was disconnected from the epidural needle, and the spinal needle was advanced through the epidural needle using a needle-through-needle approach. The spinal needle was advanced through the epidural space, dura mater, arachnoid mater, and subarachnoid space. Once the subarachnoid space was reached, the spinal stylet was removed and free-flowing cerebrospinal fluid (CSF) was observed through the spinal needle. After observation of CSF aspiration, the intrathecal medication was administered. Aspiration of the spinal needle was performed before and after medication administration to confirm maintained position of the spinal needle. The spinal needle was subsequently removed, and the epidural catheter was threaded into the epidural space. The epidural needle was removed using a push-pull technique with the epidural catheter. The epidural catheter was left 5 cm into the epidural space. The epidural catheter was aspirated with a 1-mL syringe to confirm negative aspiration. To minimize the time spent in the sitting position after intrathecal dosing and reduce the risk of saddle block, the patient was placed in the lateral decubitus position, and the epidural catheter was then secured with Tegaderm (3M, St. Paul, Minnesota) and Micropore tape (3M, Maplewood, Minnesota, USA). A bilateral sensory level to T4 was achieved within 8 minutes.

Typically, spinal anesthesia includes a local anesthetic, commonly bupivacaine, combined with an opioid.² Hypobaric or hyperbaric (addition of glucose 80 mg/mL) bupivacaine can be used,² with the latter being most common. The addition of glucose to bupivacaine creates a solution that is denser than CSF and allows for better spread of solution. The addition of opioids improves intraoperative and postoperative analgesia. Lipophilic opioids, such as fentanyl, with an onset of 10–20 min, improve intraoperative analgesia and reduce intraoperative nausea/vomiting.² Hydrophilic opioids, such as morphine, have a slower onset (45–60 min) and longer duration of action (12–36 h), and are primarily used for their postoperative analgesic effects. Neuraxial opioids can be associated with side effects such as nausea, vomiting, pruritus, sedation, and respiratory depression. Therefore, proper postoperative respiratory monitoring should be employed according to SOAP recommendations: respiratory rate and sedation measurements should be taken every 2 hours for the first 12 hours postoperatively. For patients who screen as high risk for postoperative respiratory depression, these measurements should increase to hourly for the first 12 hours and then every 2 hours from 12 to 24 hours, with pulse oximetry added.⁷

The routine intrathecal solution utilized at our institution for cesarean delivery is intrathecal hyperbaric bupivacaine 12 mg with intrathecal fentanyl 15 mcg and morphine 100 mcg. In order to avoid maternal hypotension, a prophylactic phenylephrine infusion was started immediately after the intrathecal dose at 0.5 µg/kg/min, adjusted to maintain mean arterial pressure (MAP) within ±20%. No maternal hypotension and no maternal bradycardia were observed. Although the epidural catheter was placed as a potential backup for top-up, it was not used intraoperatively and was removed in the postanesthesia care unit (PACU), as the surgery lasted approximately 100 minutes. Postoperative analgesia was managed with intrathecal morphine plus scheduled acetaminophen and ibuprofen, with oxycodone as needed.

The use of neuraxial anesthesia for cesarean delivery is strongly supported by obstetric anesthesia guidelines.^8,9 Neuraxial anesthesia provides an optimal patient experience and contributes greatly to enhanced recovery protocols. The successful delivery of neuraxial anesthesia for cesarean delivery requires a patient-centered approach and is an essential component of modern obstetric care.

Disclosures

We report no conflicts of interest, financial relationships, funding, sponsorship, equipment support, or other relationships that could be perceived to influence the content of this article.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.