Learning Objectives:After participating in this continuing professional development activity, the provider should be better able to:

1. Describe the risk and impact of the use of opiates for pain relief in association with cesarean delivery.

2. Explain preoperative and intraoperative options to reduce pain and enhance postoperative recovery.

3. Recommend postoperative measures to enhance postoperative pain relief and recovery.

As physicians and surgeons, obstetricians are acutely aware of the nationwide opioid crisis and the importance of decreasing opioid use both inside and outside of the hospital setting. In one review of perioperative use, it was found that 6% to 10% of patients who underwent either minor or major surgery, not specific to obstetrics and gynecology procedures, were still using opioids 1 year after their procedure.1 This same review noted that opioid dosing during the operative procedure was positively correlated with the postoperative opioid requirement for analgesia. This is thought to be due to acute tolerance secondary to opioid-induced hyperalgesia, indicating that patients who receive more opioids intraoperatively become sensitized and thus require more opioids postoperatively.1

These concerns also translate into the peripartum period, especially for patients requiring cesarean deliveries. In 2019, Peahl and colleagues2 reviewed rates of new persistent opioid use in recently delivered patients and found that 75% of patients who underwent cesarean delivery were discharged with an opioid prescription. Of these women, 1% to 2% became persistent users. When compared with the nationwide cesarean delivery rate, that is an astonishing number of new persistent opioid users.

Obstetricians have a responsibility to manage pain effectively, while also working to decrease the risk of patients becoming persistent opioid users. This article presents options to support a multimodal approach to peripartum and perioperative pain management for patients undergoing cesarean delivery. It is the physician's role to evaluate each patient and personalize their pain control regimen, so patients may effectively meet postoperative milestones, care for their newborns, be discharged home from the hospital in a timely manner, and avoid prolonged narcotic use.

Preoperative Pain Control

Oral Agents

When evaluating oral pain control agents during the antepartum period, the list is very limited. Oral acetaminophen is a well-studied antipyretic and analgesic in pregnancy. The mechanism of action is thought to be through indirect cyclooxygenase inhibition though it does not have an effect in peripheral tissues.3 According to both the American College of Obstetricians and Gynecologists (ACOG) and the Society of Maternal Fetal Medicine (SMFM), this medication is not associated with risk to fetal development if taken appropriately. Per Enhanced Recovery After Surgery (ERAS) guidelines, the recommended dose is 1000 mg by mouth one time within 1 hour of delivery.4

Historically, gabapentin, a medication that decreases presynaptic calcium channels, thus decreasing neurotransmitter release, was used for control of neuropathic pain. However, there are mixed data regarding its effectiveness.4 A systematic review of gabapentin use preoperatively for a variety of surgeries published in 2016 did not find benefit in postoperative pain scores.5,6 Additionally, Monks and colleagues7 published a single-center randomized control trial comparing the addition of gabapentin pre- and postoperatively to a multimodal pain control regimen and found minimal improvement in pain control with increased sedation in patients receiving scheduled gabapentin after their cesarean delivery.

Intraoperative Pain Control

Neuraxial Anesthesia

In the setting of a planned cesarean delivery, evaluation preoperatively with an anesthesia provider is always recommended to determine the appropriate type of regional anesthesia. The options for neuraxial anesthesia include spinal or epidural anesthesia. Epidural anesthesia allows for longer and continuous pain control, whereas spinal anesthesia provides anesthesia for 2 to 3 hours. They both include the use of a local anesthetic, typically lidocaine 5% or bupivacaine 0.75%.8 Many studies have compared postoperative pain control in patients whose spinal contained local anesthetic alone versus the addition of intrathecal morphine or hydromorphone with most finding that patients had improved pain scores and reduced opioid use postpartum with the addition of narcotic medication. However, patients receiving intrathecal morphine or hydromorphone also reported a higher incidence of nausea, vomiting, and pruritis.5 Although neuraxial anesthesia is used regularly in obstetrical care, it is not without risks. One of the more serious risks is that of spinal or epidural hematoma. In obstetric patients, this risk is about 0.54/100,000.9 Patients with bleeding disorders or with gestational diseases causing thrombocytopenia may be at higher risk of hematoma formation. For this reason, many anesthesiologists and institutions establish a platelet count below which they would not recommend placement of a spinal or epidural anesthesia, typically in the range of 70,000 to 80,000.9 Other side effects include headache, infection, and pain at the injection site. There are times when adequate pain control cannot be obtained with neuraxial anesthesia, or a cesarean delivery might be emergent and not allow for placement of a spinal. In these cases, general anesthesia must be used, and the addition of other pain control modalities should be discussed with the care team.

Intravenous Agents

Opioids are among the more commonly used medications used intraoperatively across surgical specialties. In obstetrics, we work to decrease the amount of opioids given intraoperatively because of the risk of neonatal sedation. Additionally, as discussed previously, increased opioid use intraoperatively can lead to increased use postoperatively. Therefore, IV opioid use should be limited at the time of cesarean delivery. For example, if neuraxial anesthesia is noted to be inadequate during a cesarean delivery, ketamine may be considered as an additive agent rather than opioids. One small study found that postspinal injection of a subanesthetic dose of IV ketamine (0.15 mg/kg) provided intraoperative pain relief and reduced postoperative opioid use without impacting Apgar scores.10 The most common side effects reported included vomiting and hallucinations. Appropriate counseling of support persons who might be present at the delivery is encouraged because certain hallucinations might be alarming.

Administration of dexamethasone at the time of cesarean delivery after delivery of the neonate is debated. It has been demonstrated to improve pain scores by prolonging analgesic effects and reducing postoperative nausea and vomiting.5,11 However, in patients already receiving multimodal pain control, dexamethasone administration did not show a reduction in opioid consumption with a single 8-mg intraoperative dose.12 Research is lacking in patients who have received recent courses of antenatal corticosteroids for fetal indications. Aasboe and colleagues13 described the use of betamethasone preoperatively for nongynecologic or obstetric surgery and found a decrease in pain and postoperative nausea and vomiting. In their study, the treated group received a single 12-mg injection of betamethasone preoperatively and had significantly decreased pain scores postoperatively. One could extrapolate, though with caution, that recent administration of betamethasone (typical regimen for fetal lung maturation is 12 mg daily for 2 doses) might have similar effects for patients being delivered by cesarean delivery.

Local Infiltration

Injection of local anesthetics after fascial closure is a widespread practice across surgical specialties. There are several local anesthetics that come in varying strengths and with varying half-lives. The most commonly used agents are lidocaine and bupivacaine, though this may vary based on institution and available supplies.8 Injection of local anesthetic into the incision is especially recommended if long-acting intrathecal opioids are not given.14 For longer duration pain control, providers can consider placement of a local anesthetic pump before closure of the subcutaneous tissue. Typically, when using these devices, the wound is infiltrated with local anesthetic, the pump is placed, and the incision closed. The pump will then infuse the local anesthetic of choice at a set rate and is then removed at the bedside before discharge. Several small studies have evaluated the use of a pump system after cesarean delivery and gynecologic surgery with mixed results. Pain scores tend to be improved though overall pain medication consumption was not significantly reduced.15,16 Another study by Masaracchia and colleagues17 demonstrated enhanced pain control with the addition of the soaker pump, though the difference only became statistically significant with the addition of scheduled acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs).

Regional Anesthesia

In facilities with appropriately trained anesthesiologists, providers can consider the addition of regional anesthesia nerve blocks including the transverse abdominis plane (TAP) block or quadratus lumborum (QL) block. The limiting factor for use is a provider trained and experienced in these specific modalities. TAP blocks are placed abdominally and cover nonvisceral pain receptors around the incision. QL blocks may spread to the paravertebral space and thus can add visceral pain control though this is not guaranteed. A systematic review by Blanco and colleagues18 found that TAP and QL blocks were as effective as intrathecal morphine without the side effects of nausea, vomiting, and pruritus, although the quality of trials reviewed was mixed with variation in medications used in both spinal anesthesia and nerve blocks. Given this information, nerve blocks can be a worthwhile option in patients who have not received neuraxial anesthesia with an intrathecal long-acting opioid.

Postoperative Pain Control

Oral Agents

Once the baby has been delivered, the options for maternal oral pain medications are broadened. ERAS protocols for many surgical procedures, including cesarean delivery, recommend use of scheduled acetaminophen 1000 mg every 6 hours and scheduled NSAIDs.14 The protocols for NSAIDs may vary between institutions, though a common regimen is IV ketorolac 15 mg or 30 mg initiated immediately after cesarean delivery for a set number of doses (such as 15 mg IV every 6 hours for 24 hours) followed by oral ibuprofen 600 mg every 6 hours thereafter.5,14 There has been debate regarding dosing acetaminophen and NSAIDs together every 6 hours versus alternating every 3 hours and whether one regimen is superior to the other. Masaracchia and colleagues17 also studied this and found the difference in pain control was not significant. In fact, there could be a reduction in nursing burden and interruptions for patients if given every 6 hours together.

Gabapentin, as described earlier, has also been used in ERAS protocols for postoperative pain management. Again, studies have demonstrated mixed benefits of adding gabapentin to a multimodal pain regimen, especially if NSAIDs and acetaminophen are scheduled, though gabapentin may help reduce nausea and vomiting.5,19 Patients should be counseled about the side effects of gabapentin including sedation and dizziness.19

Cyclobenzaprine 5 to 10 mg every 8 hours may be considered for postoperative pain control related to musculoskeletal pain or muscle spasm. There are limited data regarding this medication postpartum after cesarean delivery, but one study suggests that adding cyclobenzaprine to an NSAID regimen may provide some benefit.20 This must be weighed against the sedating effects and should be discontinued if it prevents patients from safely caring for their newborns.

Opioids can still have a role in providing postpartum pain relief. There are several options for opioid medications including, but not limited to, oxycodone, hydromorphone, meperidine, and tramadol. The mechanism of action is similar for these medications in that they are [micro]-opioid receptor agonists that inhibit voltage-gated calcium channels and decrease neurotransmitter release.3 As discussed previously, these medications can be useful because they have a quick onset of action and are effective at reducing pain. They can have several side effects including nausea, vomiting, constipation, and sedation, and quite obviously can be habit forming.

Intravenous Agents

As discussed previously, ketorolac is a common nonopioid IV medication given for postoperative pain management. Concern has been raised regarding administration of ketorolac postpartum because this medication can cause prolonged bleeding time and decreased platelet aggregation. An ongoing study has provided initial data reinforcing the observation of decreased platelet aggregation after cesarean delivery, though the impact on patient blood loss or delayed postpartum hemorrhage is unclear.21 This study should not preclude ketorolac use, but caution should be used in the setting of postpartum hemorrhage.

Providers can also consider use of IV opioid agents, which have the same mechanism of action as oral agents though usually with faster onset of clinical effect. Opioids can be administered intravenously either by nursing administered doses or patient-controlled analgesia (PCA). Institutions vary in the medications they use in PCAs. Studies have compared use of an opioid alone versus an opioid and local anesthetic or dexmedetomidine (an [alpha]2a adrenergic receptor agonist). There is a suggestion that addition of dexmedetomidine improved pain scores, but the results were not statistically significant. There was no benefit found to adding local anesthetic.5

Topical Agents

Lidocaine patches may be considered as an adjunct to the above options. Lidocaine is a common medication for anesthesia, analgesia, and cardiac arrhythmia. When applied in patch form, it provides pain relief by blocking sodium channels on nociceptors without affecting A fibers. This results in a reduction of pain impulses and reduction of pain perception without causing numbness of the skin underlying the patch. Many studies in obstetrics and gynecology and other specialties have demonstrated a decrease in pain scores with use of lidocaine patches for up to 48 hours after surgery. These studies, save one, did not show a reduction in opioid consumption or a change in recovery time.22-26 Lidocaine patches (5%) may be applied directly around the incision, typically 1 cm above and below, for 12 hours with reapplication every 12 to 24 hours.

Conclusion

As cesarean deliveries are 1 of the 5 most performed surgeries in the United States and carry significant costs to the hospital system, it is imperative that providers think critically about perioperative pain management to reduce hospital stay length due to pain and to decrease outpatient opioid prescriptions after delivery. The ACOG and ERAS protocols recommend a multimodal approach to pain control that maximizes the use of NSAIDs and acetaminophen. Depending on availability and experience of anesthesia providers, neuraxial anesthesia with a long-acting opioid has been demonstrated to decrease pain after delivery during the first 24 to 48 hours. If not available, consideration of a nerve block such as TAP or QL, wound infiltration with local anesthetic, or use of lidocaine patches should be considered. When pain is well controlled, patients are more likely to ambulate, orally hydrate, breastfeed, and care for their newborns safely and effectively. Improved pain control may also allow patients to be discharged sooner from the hospital, reducing the cost of delivery to the patient and health care system. Finally, with maximization of nonopioid pain control modalities, the number of patients discharged with opioid prescriptions can be reduced with a resultant decrease in the number of our patients who become persistent opioid users.

References