1

Introduction

Caesarean delivery (CD) is the most performed inpatient surgery worldwide. Rates of CD are rising, and projected to account for almost one third of all deliveries by 2030 [ , ]. This will increase healthcare service utilization and expose greater numbers of relatively young and otherwise healthy patients to major abdominal surgery. Improving maternal recovery after CD has important benefits to both mother and newborn, at a time of increased maternal mental and physical demand in the early postpartum period. Adoption of a multidisciplinary, holistic approach to perioperative care could facilitate maternal postsurgical recovery and reduce surgical complications such as the development of chronic postsurgical pain and other maternal physical and mental health problems [ ]. Furthermore, improved early postpartum maternal health may improve maternal-neonatal bonding that is advantageous for infant development, and yields economic benefits [ , ].

2

Enhanced Recovery After Caesarean

Enhanced recovery after surgery (ERAS), a fast-track perioperative pathway, is currently utilised by the majority of surgical subspecialties [ ]. By reducing the stress associated with surgery, this evidence-based, multimodal, multidisciplinary approach can improve postoperative outcomes, reduce hospital length of stay (LOS), and lower healthcare costs. While ERAS protocols vary by surgical subspecialty, many share common elements. Enhanced Recovery After Caesarean (ERAC) builds upon ERAS principles to address the unique needs and challenges of obstetric patients [ ]. Through patient empowerment and incentivised adherence to high-quality perioperative care, ERAC has been associated with improved maternal and neonatal outcomes. It aims to optimise maternal and fetal outcomes through preoperative counseling, tailored anesthesia techniques, and individualized pain management strategies. Additionally, ERAC emphasises the importance of early breastfeeding initiation and support, as well as promoting maternal-infant bonding during the recovery period. The implementation of ERAC has shown promising results in reducing complication rates [ , ]. The ERAS Society, the Society for Obstetric Anesthesia and Perinatology (SOAP) and the Enhanced Recovery Canada Clinical Pathway for Caesarean Delivery each recently released ERAC recommendations [ ].

3

Society for Obstetric Anesthesia and Perinatology guidelines

The 25 interventions that SOAP recommends are: limiting the duration of fasting; nonparticulate liquid carbohydrate loading; patient education; promotion of breastfeeding and maternal-infant bonding; hemoglobin optimisation; prevention and treatment of hypotension caused by spinal anesthesia; maintenance of normothermia; optimising uterotonic administration; antibiotic prophylaxis; initiation of multimodal analgesia; IONV/PONV prophylaxis; intravenous (IV) fluid optimisation; delayed umbilical cord clamping; venous thromboembolism prophylaxis, encouraging rest periods; early mobilisation; early urinary catheter removal; early oral intake; facilitating early discharge; anaemia remediation; breastfeeding support; multimodal analgesia; glucose control; and promotion of the return of bowel function [ ].

4

Enhanced recovery after surgery society guidelines

The ERAS Society has few recommendations specific to CD. They include delayed cord-clamping, prioritizing a transverse uterine hysterotomy, use of subcuticular sutures, and removal of the urinary catheter in the immediate postoperative period [ ].

5

Enhanced recovery Canada guidelines

A comprehensive pathway from Enhanced Recovery Canada was published in December 2022 that includes all the components of ERAC covered in the current SOAP recommendations [ ]. Patient optimisation is further emphasized compared to SOAP to include antenatal maternal mental health screening for anxiety and depression and referral to mental health services [ ]. This is a timely addition, as maternal mental health is a recognized driver of maternal mortality with an increasing proportion of deaths attributable to psychiatric disease [ ].

6

Limitations of current guidelines

Current guidelines are limited in terms of the breadth of different stakeholder involvement in individual publications. For example, the ERAS Society guidelines lack United States (US) anesthesia stakeholder contribution and patient representatives, whereas SOAP guidelines are authored by US anesthesiologists only. To address this, a multidisciplinary international guideline is under development using Delphi methodology. Through sequential surveys to generate consensus, key ERAC interventions recommended across US professional societies for anesthesia, maternal-fetal medicine, obstetrics, nursing and from patient participation will be established.

7

Evidence for benefits of Enhanced Recovery After Caesarean delivery

The use of ERAC protocols has increased over the past decade. Since 2019, 2 systematic reviews and 3 meta-analyses including data from 16 trials have compared ERAC protocols to standard care. A 2021 meta-analysis by Sultan et al. included 12 trials with 17,607 women recruited between 2013 and 2019 (7914 with ERAC, 9693 without) [ ]. Ten of the 12 trials showed a decrease in the main outcome measure of LOS by 0.51 days [−0.94, −0.09]; p = 0.018; I ² = 99%) after ERAC implementation. Three trials demonstrated an association of reduced time to mobilisation with ERAC (MD, −11.05 h [−18.64 to −3.46); P = 0.004; I2 = 98%). Cost effectiveness could not be analyzed due to inadequate studies providing variance data. However, 2 US studies reported significantly lower costs with the implementation of ERAC [ , ]. All outcomes evaluated to date have levels of evidence ranging from low to very low. Specifically, low-level evidence was found for LOS, time to first mobilisation, time to urinary catheter removal, and opioid consumption, while very low-level evidence was found for the outcome of readmission following hospital discharge [ ]. Meng et al. published a meta-analysis evaluating 10 ERAC trials and concluded that ERAC lowered the primary outcome of LOS and improved secondary outcomes of complication rates, pain ratings, opioid usage, and inpatient expenses [ ]. Rates of readmission for mothers were no different between ERAC and standard care groups. A 2024 meta-analysis including 16 studies (3 randomized controlled trials, 4 prospective cohorts and 9 retrospective cohorts) capturing 19,001 women found that ERAC was associated with shorter LOS (MD: 13.78 h; CI 95 % −19.28 to −8.28; p < 0.00001) and lower opioid consumption (MD: 0.91; CI 95 % −1.51 to −0.32; p = 0.003). Importantly, there was no concurrent increase in readmission rates (OR: 0.85; CI 95 % 0.50 to 1.44; p = 0.53) or maternal complications of surgical site infection (OR: 1.13; CI 95 % 0.72 to 1.77; p = 0.60) or postoperative nausea and vomiting (PONV; OR: 0.78; CI 95 % 0.31 to 1.96; p = 0.60).

8

Core outcome set

The heterogeneity of clinical outcomes used in existing ERAC studies makes it challenging to gather high-quality data via meta-analysis [ ]. A core outcome set (COS) is an agreed minimal group of outcomes to be collected in all clinical studies for a condition or context. This methodology has been recommended by the Core Outcome Measures in Effectiveness Trials (COMET) initiative to lower heterogeneity in clinical research that has hindered therapeutic advancements [ ]. A COS for ERAC has been developed via Delphi-derived consensus among 32 stakeholders, yielding 15 core recommended outcomes [ ]. Use of this proposed COS may improve the future of evidence, data sharing, and the effectiveness with which ERAC programs are established. The COS is pragmatic: it includes LOS, which is easily collected but vulnerable to influence by non-clinical factors such as institutional delays, and so may have limited reliability as a clinical effectiveness outcome measure. The use of COS in obstetrics research may lead to more uniform and comparable data across trials, improving the ability to evaluate the efficacy of treatments and ultimately enhance patient care. Future studies are warranted to explore more sophisticated or tailored outcomes such as patient-reported time ready for discharge and the creation of instruments to capture this [ ].

9

Outcome metrics for quality assurance after cesarean delivery

Measuring the quality of care received by patients is instrumental to highlight areas of concern, direct improvements to obstetric anesthesia services, and optimise maternal recovery after childbirth. The American Society of Anesthesiologists (ASA) has published recommendations for content of obstetric quality assurance dashboards [ ]. Metrics relevant to CD are summarised in Table 1 .

10

Clinical outcome assessments used to assess postpartum recovery after CD

Various clinical outcome assessments (COAs) can be utilised to comprehensively evaluate recovery after CD. Such COAs include patient-reported outcome measures (PROMs), observer-reported outcome (ObsRO) measures, clinician reported outcome (ClinRO) measures and performance outcome (PerfO) measures [ ]. At 50 days postpartum, approximately 10% of women who undergo CD have yet to fully recover (as defined by pain resolution, cessation of opioids, and self-assessed functional recovery) [ ]. Despite this challenge, there is limited guidance for assessing postpartum recovery, and until recently it remained poorly defined. Sultan et al. have qualitatively explored postpartum recovery and described it as a multidimensional and dynamic process involving the interaction of a number of health domains [ ]. Thirteen postpartum recovery domains were identified following a qualitative study involving 50 stakeholder interviews of postpartum patients, obstetricians, maternal–fetal medicine specialists, nurses, a midwife, and obstetrical anesthesiologists. The domains (ranked highest to lowest in order of weighted importance) were psychosocial distress, surgical/medical factors, infant feeding and breast health, psychosocial support, pain, physical function, sleep, motherhood experience, infant health, fatigue, appearance, sexual function, and cognition. Several factors facilitating recovery were identified, including family support, breastfeeding support, and partner support. Inadequate family and partner social support was perceived factors that most hindered recovery. A better understanding of postpartum recovery profiles and trajectories after ERAC, including subgroups based on different patient and surgical factors, is essential for further refinement of ERAC protocols. No studies to date have comprehensively explored ERAC protocol impact on the 13 postpartum recovery domains, as most studies have been inpatient-focused. For example, postpartum depression usually presents in the outpatient setting, and sleep disorders such as insomnia tend to not be a significant feature associated with quality of inpatient postpartum recovery. Early improvements in maternal recovery after CD may have significant implications on longer term maternal morbidity and even mortality. Hayoun et al. found that the 24 h postoperative ObsQoR-10 recovery metric of ‘I feel in control’ was inversely associated with 6-week depression symptoms [ ]. Research on the intersection of ERAC protocols and PROMs will optimise recovery after CD and can focus on improving maternal mental health, including more biopsychosocial approaches to pain management and care in the early postpartum period to improve maternal empowerment. Table 2 summarizes the best available validated PROMs that have been identified in a series of systematic reviews to assess individual postpartum recovery domains and global quality of recovery. Obstetric specific PROMs are currently lacking for most domains of postpartum recovery (e.g., pain, sleep, anxiety, fatigue and global recovery).

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Postpartum analgesia

Postpartum analgesia is a critical component of maternal recovery, with the aim to mimimize pain and enhance the postpartum experience for women after childbirth. Optimal analgesia is instrumental for achieving most of the other ERAC milestones such as early mobilisation, catheter removal and ability to successful breastfeeding. Choice of analgesic modality involves careful consideration of the effectiveness, safety, and potential impact on the mother and newborn. Evidence supports the use of a multimodal approach, combining different pharmacological agents for synergistic effects and minimisation of opioid use. A multimodal regimen with intraoperative IV dexamethasone, fixed doses of paracetamol/acetaminophen, and nonsteroidal anti-inflammatory drugs (NSAIDs) can effectively reduce post-cesarean opioid use. A gold standard opioid-sparing perioperative regimen is summarised in Table 3 , adapted from the Procedure Specific Postoperative Pain Management (PROSPECT) guidelines for pain management after CD [ ].

Pain is the best studied domain of postpartum recovery that can be treated by anesthesiologists to optimise quality of recovery and quality of life. Surveys from the United Kingdom (UK) and Australia demonstrate that patients experience symptoms such as extreme tiredness, backache, headache, bowel problems, urinary incontinence, lack of sleep, haemorrhoids, perineal pain and mastitis up to 18 months postpartum [ ]. Current evidence suggests that the relatively low occurrence of chronic pain after CD [ ] compared to other surgical procedures may be attributed to factors such as neuraxial anesthesia and potential protective effects from endogenous oxytocin secretion. Neuraxial anesthesia during CD, particularly when intrathecal opioids are administered, may play a role in preventing the development of chronic pain, although current evidence does not support the role of intrathecal morphine (ITM) for this purpose [ ]. A comprehensive systematic review and meta-analysis reported an 15.4% incidence of chronic pain at 3–6 months postpartum, with 49.2% reporting the pain to be ‘mild’ at 6 months [ ]. What is not fully investigated however is the significance of this pain on maternal health-related quality of life, and qualitative research to better understand the biopsychosocial impacts.

12

Neuraxial anesthesia

Neuraxial anesthesia is recommended for CD by SOAP, the Obstetric Anaesthetists’ Association, American Pain Society and the National Institute for Health and Care Excellence [ , ]. Intrathecal fentanyl and ITM are the preferred neuraxial adjuvants to local anaesthetic agents for CD anesthesia and analgesia. A dose-response study showed that 50 mcg ITM was as effective as 100 and 150 mcg [ ]. A meta-analysis concluded that high doses >100 mcg were more likely to be associated with adverse side effects [ ]. It is important to identify women with increased risk of respiratory depression, as they might require more intensive postoperative monitoring after ITM. The rate of clinically significant respiratory depression following contemporary doses of ITM is 1.08–1.63 per 10,000 [ ]. To address this concern, SOAP published a consensus statement on monitoring for respiratory depression after ITM. For patients considered low risk for respiratory depression receiving ITM (>0.05 to ≤0.15 mg) or epidural morphine (>1 mg to ≤3 mg), it is reasonable to deploy respiratory rate and sedation measurements every 2 h for 12 h [ ]. If neuraxial morphine cannot be used, abdominal wall blocks or surgical wound infiltration are valuable alternatives. Patients with opioid use disorder may benefit from postpartum epidural analgesia. In such cases, providing two neuraxial techniques including a residual low thoracic epidural can provide analgesia with less delay in postoperative mobilisation [ ].

13

Nonopioid analgesics

Acetaminophen is recommended as part of an opioid sparing strategy. Findings of benefit are mixed, with one trial associating IV administration with lower opioid consumption [ ] and another demonstrating no benefit to pain outcomes with pre-operative administration, including number of postoperative opioid doses, morphine milligram equivalents administered, pain scores, or length of hospital stay [ ]. Nonsteroidal anti-inflammatory drugs (NSAIDs) provide analgesia by inhibiting prostaglandin synthesis. They are preferred for mild to moderate pain and are considered safe during breastfeeding. A recent meta-analysis found that NSAIDs reduce opioid consumption and pain scores and improve patient satisfaction after CD [ ]. The optimal NSAID and dosing regimen following CD remains unclear [ ]. However, NSAIDs should be prescribed in a scheduled manner rather than as-needed, as this strategy has been shown to reduce opioid consumption following caesarean delivery [ ].

14

Dexamethasone

Intravenous dexamethasone during CD has been associated with better pain scores and prolonged analgesia [ ] with reduced need for further anti-emetics [ ]. Application by wound infiltration was found to be superior to IV administration in one study [ ]. A meta-analysis and trial sequential analysis showed that in patients who received dexamethasone during CD, early pain scores were reduced by −1.29 [95% confidence interval (CI), −1.85 to −0.73], P < 0.0001 and analgesia was prolonged by 2.64 h (95% CI, 1.85 to 3.42, P < 0.001) compared to controls, and opioid consumption was reduced 9.59 mg (95% CI, 11.44 to 7.73, P < 0.00001) morphine milligram equivalents at 24 h [ ].

15

Peripheral nerve blocks

Whilst long acting neuraxial opioids have been the standard analgesic approach for CD, alternate regimens such as peripheral nerve blocks may have utility when neuraxial anesthesia cannot be provided, such as patients with coagulopathy or who undergo an emergency CD under general anesthesia. Singh et al. [ ] [] []performed a network meta-analysis to compare and rank locoregional approaches and local anaesthetic infiltration techniques. Ilioinguinal blocks appear to have the highest efficacy, though transversus abdominis plane (TAP) and quadratus lumborum (QL) blocks have been more rigorously evaluated for postoperative CD pain.

16

Transversus abdominis plane blocks

Transversus abdominis plane (TAP) blocks involve the administration of local anaesthetic into the transversus abdominis plane, a fascial plane between the internal oblique and transversus abdominis muscles [ ]. Bilateral blockade of these nerves can reduce somatic pain, but not visceral pain associated with CD [ ]. Numerous studies have investigated the analgesic effectiveness of TAP blocks for CD, with many trials reporting reductions in pain scores after TAP block administration in the absence of ITM. The benefit of additional TAP blocks in the presence of ITM is less clear however, due to heterogeneity of studies [ , ]. In the first 24 h after CD, TAP blocks reduce resting and dynamic visual analogue scale (VAS) pain scores in patients who did not receive ITM. Beyond this time frame, the effects are less clear. A meta-analysis by Ng et al. [ ] demonstrated that a low dose of local anaesthetic (≤50 mg bupivacaine equivalents per block side) conferred similar analgesic efficacy compared with high-dose local anesthetics (>50 mg per block side). These findings suggest that lower local anaesthetic doses can be used to minimize the risk of local anesthesia systemic toxicity (LAST) without compromising the analgesic efficacy. As utilization of peripheral nerve blocks evolves in obstetric patients, the risk of LAST and preparedness to respond with advanced cardiac life support and rapid administration of 20% IV lipid emulsion is important, along with efforts to identify minimally effective local anaesthetic dosing for safety [ , ].

17

Quadratus lumborum blocks

Lateral, posterior and anterior quadratus lumborum (QL) block approaches can be performed with the patient in supine position [ , ]. Due to the potential spread of local anaesthetic in the paravertebral space, the QL block can be therapeutic for both somatic and visceral pain with potential superiority compared to TAP blocks [ ]. A meta-analysis by Zhao et al. [ ] reported that, similar to TAP blocks, QL blocks provide greater analgesia and reduced postoperative opioid requirements in patients untreated with ITM. Furthermore, time to first analgesic requirement was also significantly reduced. El-Boghdadly [ ] et al. performed a network meta-analysis comparing TAP blocks to QL blocks. In the presence of ITM, there was no difference in pain scores between control, TAP and QL blocks. A recent meta-analysis demonstrated benefits of QL blocks in addition to intrathecal opioid for acute pain, but further studies are needed to determine whether QL blocks impact the evolution of chronic pain [ ]. In the absence of ITM, QL and TAP blocks were both superior in providing analgesia compared to inactive control groups, though no significant difference was demonstrable between TAP and QL block groups. Further research is required to distinguish between these two blocks, whether QL blocks provide analgesic benefit when neuraxial analgesia is contraindicated, and whether special patient populations such as those with chronic pain or opioid use disorder may benefit more from TAP or QL blocks.

18

Wound infiltration and wound catheters

Wound infiltration involves the administration of a local anaesthetic agent directly into the surgical wound or the incision site [ , ]. Wound catheters enable continuous postoperative analgesia to the surgical site [ , ]. While both techniques provide localised pain relief at the surgical site, they may not offer the same level of analgesia as neuraxial anesthesia [ , ]. A meta-analysis by Adesope et al. [ ] showed that in the presence of ITM, wound infiltration during CD added no benefit. Research does not support the superiority of wound infiltration or wound catheters over neuraxial opioid administration but either may have value when neuraxial anesthesia is contraindicated. A network meta-analysis showed no difference between TAP vs wound infusion vs. wound catheters, and all improved analgesia in the absence of ITM [ , ].

19

Erector spinae plane (ESP) block

In patients undergoing CD without intrathecal opioids, a bilateral ESP block at the T9 level significantly reduced 24-h postoperative fentanyl consumption and prolonged the time to the first analgesic requirement [ ]. Comparative studies with the TAP block favored ESP, showing superior analgesic efficacy and more prolonged effects [ , ]. Additionally, a randomised controlled trial comparing the ESP block to ITM revealed that the ESP group required less tramadol consumption for up to 48 h and had a longer time to the first analgesic request [ ].

20

Liposomal bupivacaine

Liposomal bupivacaine is encapsulated within lipid-based nanoparticles to create a sustained-release effect for prolonged duration of analgesia. The current evidence of analgesic benefit of liposomal bupivacaine is still unclear. A systematic review and meta-analysis by Dinges et al. [ ] showed some benefit for the use of liposomal bupivacaine for local anesthesia infiltration and regional anesthesia in abdominal, hip, knee and hand surgery. Liposomal bupivacaine was also supported by another systematic review for benefit in peripheral nerve blocks [ ]. However, the evidence regarding the use of liposomal bupivacaine in CD is scarce. One RCT showed benefit, but further studies are needed to corroborate the findings [ ]. A single-center retrospective study [ ] showed reduced morphine consumption in the liposomal bupivacaine group in comparison with plain bupivacaine in TAP blocks. However, in comparison with ITM [ ], liposomal bupivacaine did not reduce pain scores. The utility of liposomal bupivacaine during CD remains equivocal and further investigations may be warranted.

21

Patients at risk for postoperative pain

The incidence of chronic post-surgical pain after CD is 15.4% at 3–6 months postoperatively [ ]. It is currently unclear the interference this pain has on maternal health-related quality of life, which could be considerable in some patients. To date, studies have not provided evidence that perioperative analgesia impacts long-term pain outcomes after CD and so the best preventive strategy for chronic post-surgical pain remains unknown [ , ]. To comprehensively address the nuanced aspects of postoperative CD analgesia, there is a pressing need for enriched population studies. It is crucial to explore whether peripheral nerve blocks offer specific benefits to subgroups of parturients with distinct clinical characteristics. Several key factors warrant particular attention in these studies, including the presence of chronic pain, opioid use disorder (OUD) and a history of severe pain following CD. Parturients with chronic pain may exhibit altered pain perception and sensitization, complicating pain management during and after CD [ ]. PROSPECT guidelines recommend the use of postpartum epidural analgesia for OUD [ ], due to the significantly increased postoperative opioid requirements expected.

22

Use of gabapentin

Gabapentin is primarily used to treat epilepsy and neuropathic pain but has shown promise as an adjunctive analgesic in various pain management settings. It exerts its analgesic effect by modulating the activity of voltage-gated calcium channels and enhancing gamma-aminobutyric acid inhibitory neurotransmission. These mechanisms are thought to reduce pain signaling and dampen the central sensitization associated with postoperative pain. Gabapentin for post-CD analgesia has been investigated in several studies [ ], including a meta-analysis by Felder et al. and recent RCT by Fowler et al. showing no significant differences between pre- and postoperative gabapentin and placebo on pain scores, use of additional pain medications, supplemental opioids or maternal or neonatal side effects [ , ].

23

Other emerging therapies

The utilization of lidocaine patches for after CD has garnered attention for potential adjuvant postoperative pain management [ , ]. This method allows for targeted pain relief without the need for systemic administration of medications, reducing the risk of systemic side effects. While RCTs have demonstrated beneficial effects of the lidocaine patch for postoperative pain management [ , ], morphine-sparing effects in patients having CD remain unclear. A RCT performed by de Queiroz et al. [ ] investigating the efficacy of a 5% lidocaine patch following CD demonstrated a significant reduction in pain scores but no difference in opioid consumption or side effects.

24

Other symptoms which can impact post caesarean delivery recovery

Aside from pain, maternal side effects such as pruritis, shivering, and postoperative nausea and vomiting can interfere with the recovery process and patient experience. Pruritis is a frequently reported unpleasant side effect from ITM, and a recent network meta-analysis identified 5 medications as superior to placebo for treatment: propofol, neuraxial and systemic opioid agonist-antagonists, opioid antagonists, and serotonin antagonists. Further studies are needed to identify the best treatment modality and dosing strategy [ ]. Additionally, the importance of postoperative nausea and vomiting, shivering and breastfeeding ability on the postoperative CD recovery experience was identified during the development of the Obstetric Quality of Recovery Score [ ], and efforts to optimise these domains of recovery have the potential improve patient experience and satisfaction. Last, there is a growing need for research and implementation of post habilitation services, for example physical therapy, to enhance recovery.

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Summary

CD rates are increasing and are projected to account for a third of all births by 2030. There is therefore a need to improve the efficiency and outcomes of CD, and ERAC interventions are cost-effective and have been shown to improve patient outcomes, experience, and satisfaction without risking complications or maternal hospital readmission. Optimising maternal recovery after CD creates benefits for the individual, the newborn, and wider society from economic impacts. The use of standardised outcomes will facilitate the analysis of data from different studies and increase the overall quality of evidence for ERAC. By including PROMs, researchers can gain a deeper understanding of the impact of CD on women’s quality of life and overall satisfaction with their recovery. Expanded studies using the best research designs and incorporating PROMs would ensure that the perspectives and experiences of women undergoing CD are considered, further enhancing the relevance and applicability of research findings. This holistic approach to measuring postpartum recovery would provide valuable insights for healthcare providers in tailoring interventions and support services to meet the specific needs of each individual patient and promote maternal recovery.

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