Long-acting neuraxial opioids and optimal analgesia care for women undergoing caesarean delivery

Long-acting neuraxial opioids and optimal analgesia care for women undergoing caesarean delivery

  • Issue 78

Carolyn F Weiniger, Emilia Guasch, AlexandraSchyns-van den Berg
carolynfspencer@gmail.com

While caesarean delivery is the one of the most common surgical procedure performed worldwide, post-caesarean analgesia is neglected area of care. A recent study from Germany reported that women receive insufficient postpartum analgesia after caesarean delivery, and less opioids than women undergoing hysterectomy (Marcus Eur J Pain2015;19:929). In an Israeli survey, 18 units do not record pain scores after caesarean delivery. (Orbach-ZingerIMAJ 2014;16:153) Thus there appears to be a need for improved analgesia care for women undergoing caesarean delivery.

The most reliable post-caesarean analgesia is a long-acting (hydrophilic) neuraxial opioid (spinal or epidural) administered at the time of caesarean delivery. The American Society of Anesthesiologists (ASA) recommends close follow-up after administration of long-acting neuraxial opioids as they may cause late respiratory depression (ASA 2016;124:535). According to ASA guidelines, nurses must count respirations for at least 24 hours after administration; hourly for 12 hours and then 2-hourly. The Obstetric Society of Anesthesia and Perinatology (SOAP) recommend less stringent 2 hourly assessments for 12 hours, and no monitoring is required for women receiving ≤50 mcg intrathecal morphine or ≤1mg epidural morphine. (Bauchat JR Anesth Analg 2019 Epub).

It is unclear in countries where long-acting neuraxial opioids are not used for post-caesarean analgesia, if the limiting factor is availability, fear of respiratory depression, or concerns about opioid side-effects. If preservative free long-acting opioids were widely available for post-caesarean analgesia, would they be more commonly used?

An informal survey of European Society of Anaesthesiologists’ members revealed variations regarding long-acting neuraxial opioid use and respiratory monitoring recommendations for post-cesarean analgesia. While some countries such as France and Israel recommend intrathecal morphine, diamorphine is more commonly used in the United Kingdom (UK) and Malta. Many countries do not routinely use long-acting intrathecal opioids, based upon lack of availability, or a preference for alternative oral and parenteral analgesics (e.g. the Netherlands, Belgium, Spain and Germany). For respiratory monitoring, Israel and Malta follow the ASA guidelines. In France and the UK (where long-acting neuraxial opioid administration is routine), and Spain and Germany (where use is less common) no specific respiratory monitoring is mandated. However, in the Netherlands, respiratory depression is one of the concerns that limits use of long-acting neuraxial opioids for post-caesarean delivery analgesia.

An Israeli survey published in 2014 (Orbach-Zinger IMAJ 2014;16:153) revealed that only 3 departments routinely utilised neuraxial opioids for post-caesarean analgesia. Lack of nursing staff to perform respiratory monitoring was the most commonly cited reason for lack of use. A subsequent survey performed in 2016 revealed that 11 Israeli units routinely administered intrathecal morphine (Shatalin IJOA2019;38:83); this increase is considered due to awareness by anaesthesiologists, and specific respiratory monitoring guidelines published by the Israel Society of Anesthesiologists.

Spain has one of the highest rates of epidural analgesia in Europe: >85% of deliveries in some hospitals. The caesarean delivery rate in Spain is around 25% in public hospitals. General anaesthesia is rarely performed for cesarean delivery, and most women receive an epidural top-up for intrapartum cesarean delivery.http://www.mscbs.gob.es/estadEstudios/estadisticas/docs/Ev_de_Tasa_Cesareas.pdfhttp://fundaciongasparcasal.org/publicaciones/Sanidad-espanola-en-cifras-2018.pdf

For scheduled caesarean delivery in Spain, spinal anaesthesia is the most frequent modality, with additional intrathecal fentanyl. Multimodal intravenous analgesia is the most commonly used postpartum analgesia regime. Women typically spend between 2 to 6 hours in the post anaesthesia recovery unit (PACU), enabling initiation of pain control management. In some university hospitals, women with a functional epidural catheter may receive 2 mg epidural morphine. Preservative free morphine was not available in Spain until 2016, however as it is now available, some anaesthesiologists are adopting its use. In Spanish hospitals where long-acting neuraxial opioids are administered, no special monitoring is required postpartum. There are currently no specific national Spanish obstetric anaesthesia recommendations regarding postoperative monitoring after long-acting neuraxial opioid administration.

The Netherlands supports a physiological approach to pregnancy and delivery. Although the majority of deliveries no longer occur at home (13% in 2016), the epidural rate still lingers around 20% (remifentanil is becoming increasingly popular) with a national caesarean delivery rate of 15% (Perined. Perinatale Zorg in Nederland 2017. Utrecht: Perined 2019). Although a lipophilic opioid (sufentanil or fentanyl) is often added to the spinal hyperbaric bupivacaine for caesarean delivery, there is reluctance to administer long-acting hydrophilic neuraxial opioids. This is anecdotally due to previous experience using high doses of intrathecal morphine that caused itching, nausea, vomiting and an elevated risk of late respiratory depression.

No Dutch national guidelines exist regarding post-caesarean delivery analgesia, nor are there any defined requirements for postoperative monitoring. PACU stays seldom exceed one hour, as postoperative monitoring in the labor unit is preferred in order to facilitate maternal-neonatal bonding. Multimodal analgesia regimens contain paracetamol, non-steroidal analgesics and intravenous patient-controlled opioids, or intramuscular/oral opioids as required.

The likelihood of respiratory depression after longacting neuraxial opioid administration for post-caesarean delivery analgesia is very low. A recent study (Sharawi et al Anesth Analgesia2018;127:1385) reported 1.63 cases of respiratory depression per 10, 000 (95% confidence interval 0.62 to 8.77) when using a contemporary low dose of neuraxial morphine. No cases of respiratory depression after long-acting neuraxial opioids administered for post-caesarean analgesia were reported in the United States Closed Claims Analysis. This together with other similar reports suggests that respiratory depression in this population is not a significant concern.

Additional monitors such as continuous pulse oximetry and capnography have been investigated as an adjunct monitor for women undergoing caesarean delivery who receive long-acting neuraxial opioids. To date, equipment limitations in the postpartum setting such as reliability, alarms, and discomfort with monitoring devices override any proven benefit. (Weiniger et al Anesth Analg2019;128:513).

When presented with the risk-benefit, women may prefer an analgesic option without the side effects of pruritus, nausea and vomiting. Other alternatives such as a wound infiltration, transabdominus plane or quadratus lumborum blocks together with judicious round-the-clock oral/parenteral analgesics may be offered. (Blanco R et alEur J Anaesthesiol2015;32:812), (Ng SC BJA 2018;120:252).

All women deserve a suitable and sufficiently efficacious post-caesarean delivery analgesic regime. In a panel at the ESA’s Mother and Child Focus Meeting in Rome 2019, post-cesarean care will be discussed, including options for analgesia. One focus of the panel will be use of long-acting neuraxial opioids, and the incidence and detection of respiratory depression. Evidence will be presented to support widespread availability of long-acting neuraxial opioids for optimum post-caesarean delivery analgesia.