Navigating Anaesthesia Management for LSCS in a Patient with Neuromyelitis Optica Spectrum Disorder

Abstract

Background:

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune demyelinating condition primarily affecting the optic nerves and spinal cord. Anaesthetic management during obstetric procedures is challenging due to the risk of disease exacerbation and limited literature.

Case Presentation:

We present a 36-year-old gravida 2 para 1 woman with NMOSD in remission, scheduled for elective lower segment caesarean section (LSCS) at 38 weeks due to cephalopelvic disproportion. Given concerns over neuraxial anaesthesia and potential relapse, general anaesthesia was chosen. Rapid sequence induction was performed with propofol and rocuronium, maintained with sevoflurane. Perioperative analgesia included multimodal agents and bilateral transversus abdominis plane block. Neuromuscular monitoring guided reversal with sugammadex.

Discussion:

General anaesthesia is a viable option in NMOSD patients when neuraxial techniques pose increased risk. Neuromuscular monitoring is essential due to altered sensitivity to muscle relaxants. Multimodal pain control and close neurological monitoring reduce the risk of postoperative flare-ups and chronic pain.

Conclusion:

A carefully tailored general anaesthesia approach with vigilant neuromuscular and neurological monitoring is safe and effective in NMOSD parturients undergoing LSCS. Collaborative care and individualized planning are key to favourable outcomes.

Introduction

Neuromyelitis-optica-spectrum disorder (NMOSD), also known as Devic’s disease, is an inflammatory CNS disease mediated by antibodies against the CNS water channel aquaporin-4 (AQP4). It is characterised by severe optic neuritis, myelitis, and, less frequently, brainstem encephalitis.^[1–4] NMOSD is more prevalent in women than men at a ratio of 3–9:1.^[5–9] The majority of female patients have the onset of the disease in their childbearing years (15–40 years). Obstetric patients have an increased tendency for relapse, especially in the immediate postpartum period. The anaesthetic management of a parturient with NMOSD presenting for caesarean section is challenging. The choice of anaesthetic technique is highly debated and contradictory because of the rarity of the disease. Perioperative pain management of these patients is also crucial because of the increased propensity of these patients to develop chronic pain syndromes. We present a case of safe and successful anaesthetic management of a parturient with NMOSD scheduled for an elective lower-segment caesarean section.

Case Report

A 36-year-old G2P1 patient, a known case of NMOSD, was posted for an elective lower segment caesarean section (LSCS) at 38 weeks of gestation because of cephalopelvic disproportion (CPD). She had an uneventful first pregnancy 10 years ago prior to the development of the disease. She was diagnosed with NMOSD in 2016 when she presented with symptoms of optic neuritis and was managed with intravenous immunoglobulins (IVIg) and plasma exchange, and later put on oral steroids (prednisolone) for immunosuppression. She had an exacerbation of the disease in 2020 when she presented with symptoms of cervical myelitis that were managed with intravenous methylprednisolone, and she was put on azathioprine for maintenance immunosuppression. Since then, she has been in remission and has had no flare-up of the disease. She had an uneventful obstetric course and was now posted for an elective LSCS i/v/o CPD with previous LSCS. Pre-anaesthesia evaluation was unremarkable, with no neurological deficit at present. Preoperative blood investigations were normal, and after a thorough evaluation by a neurologist, we decided to go ahead with the surgery. Informed consent for general anaesthesia with the possibility of postoperative flare-up of the disease and possible need for postoperative ICU and invasive or non-invasive ventilation was obtained.

Routine ASA monitors were attached, and after pre-oxygenation, rapid sequence induction was done with Inj. Propofol (2 mg/kg), Inj.Rocuronium (1.5 mg/kg) and anaesthesia were maintained with sevoflurane, air and oxygen mixture. Neuromuscular monitoring was done intraoperatively, and a repeat dose of muscle relaxant was given accordingly. After the baby was delivered, Oxytocin was given for uterine contraction. Inj.Morphine (7.5 mg), Inj.Diclofenac (75 mg), Inj Ketamine (30 mg) and Inj.Paracetamol (1 gm) were given for perioperative analgesia. At the end of the surgery bilateral transversus abdominis plane block was given with 20 ml of 0.25% Bupivacaine on each side. The surgery was uneventful, and the neuromuscular blockade was reversed with sugammadex (2 mg/kg) after confirming adequacy for reversal of the neuromuscular blockade with the use of neuromuscular monitoring. The patient was observed in the recovery room and shifted to the ward after 2 hrs. Postoperative pain control was achieved with paracetamol, diclofenac, pregabalin and tramadol (SOS). She did not have any flare-up of the disease in the immediate postpartum period and was discharged from the hospital on the 4th postoperative day and followed up in the OPD.

Discussion

NMOSD is a rare autoimmune demyelinating disease affecting the optic nerve and spinal cord. Prevalence of the disease is higher in the Indian population (2.65 per 100,000) as compared to the West.^[8,10] It has also been found that the disease predominantly affects women, especially in the childbearing age group. Patients with NMOSD often experience significant neurological impairments, including vision loss, motor weakness, and sensory deficits.

Patients with NMOSD often have a relapsing-remitting pattern, where acute flare-ups of the disease occur, leading to neurological deficits. These flare-ups can be triggered by a variety of factors, including infections, pregnancy, and even certain medications or surgical stress. Consequently, managing patients with NMOSD in a surgical setting, particularly in obstetric procedures, requires a carefully tailored anaesthesia plan to minimise the risk of disease exacerbation. One common surgical procedure in obstetrics is the LSCS. The choice of anaesthesia technique in these patients is controversial. The demyelinating neurons of the spinal cord in these patients have an increased vulnerability to local anaesthetic agents, making central neuraxial block riskier. There are case reports that have described flare-ups of the disease in the postoperative period following neuraxial anaesthesia.^[11,12]

With General anaesthesia there is a possible need for invasive or non-invasive mechanical ventilation in the postoperative period attributed to the increased susceptibility of the neuromuscular junction to muscle relaxants causing delayed and inadequate recovery following general anaesthesia as described in a case report in which the patient required non-invasive mechanical ventilation in the postoperative period following GA in a case of NMOSD for LSCS.^[13] Intraoperative use of neuromuscular monitoring for assessing the degree of muscle block and timely use of sugammadex for reversal of the neuromuscular block helped us to circumvent the need for postoperative mechanical ventilation.

These patients are also prone to develop chronic pain. A multimodal analgesia plan with both pharmacological and non-pharmacological approaches is essential for appropriate pain control in these patients. Pharmacological agents include non-opioids (paracetamol, diclofenac, ketamine, pregabalin) and opioids. Non-pharmacological approaches like hot and cold compression, relaxation techniques and physical therapy supplement the pharmacological agents. Peripheral nerve blocks can also be used for perioperative pain control with good success rates. A very close postoperative monitoring by a neurologist for any disease exacerbation is a must.

Conclusion

The anaesthesia management of a parturient with NMOSD undergoing LSCS is complex and requires a tailored approach. General anaesthesia with the use of neuromuscular monitoring and sugammadex as a reversal agent is a safe option in patients with NMOSD, as it avoids the possible risk of disease exacerbation associated with neuraxial anaesthesia. A good multimodal postoperative pain management plan is crucial to reduce the risk of chronic pain syndromes in these patients. Close collaboration between anaesthesiologist, obstetrician, and neurologist is crucial for successful perioperative management. A thorough monitoring of neurological status in the postoperative period is necessary to detect any early signs of deterioration or flare-ups of the underlying disease. Early and timely restarting the immunosuppression in the postoperative period is essential to prevent the recurrence of the disease. Being a rare disease, further multicentre research is required for determining a safe anaesthetic plan in these patients, and this case adds to the safe and successful use of general anaesthesia in patients with NMOSD.