Efficacy of combined spinal–epidural anaesthesia in mitigating cardiovascular stress during emergency caesarean section in a primigravida with ruptured right sinus of Valsalva aneurysm – A case report

Dear Editor, A sinus of Valsalva aneurysm (SOVA) is a rare cardiac abnormality, typically congenital, with an incidence of 0.1%–3.5%.[1] It can be acquired from connective tissue disorders or following heart valve or ventricular septal defect repair.[1,2] If ruptured, it can lead to aorto-cardiac shunt (left–right), posing risks for pulmonary congestion and congestive heart failure, dysrhythmia, myocardial ischaemia, infective endocarditis and cardiac tamponade.[1-4] Here, we describe the management of a successful emergency lower segment caesarean section (LSCS) under combined spinal epidural (CSE) anaesthesia in a haemodynamically compromised patient with a ruptured right SOVA. A 20-year-old (height- 170 cm) primigravida at 36 weeks gestation with a history of ventricular septal defect and aortic valve repair at 7 years of age presented with non-reassuring foetal cardiotocography, requiring an LSCS. She had experienced breathlessness and chest pain at around 20 weeks of gestation. She underwent 2D echocardiography, which revealed a small, ruptured right SOVA into the right ventricle (~4 mm), severe eccentric aortic regurgitation and a tiny peri-membranous residual ventricular septal defect. She was prescribed oral isosorbide and hydralazine once a day, and despite counselling for antenatal surgical repair, she declined. Serial echocardiograms throughout her pregnancy showed no worsening. A 12-lead electrocardiogram showed normal sinus rhythm. Her risk of maternal cardiac complications, based on cardiac disease in pregnancy risk score (CARPREG) II, was low at 10%. Clinical examination revealed a continuous murmur and a palpable thrill. A high-risk consent was obtained, and anti-aspiration prophylaxis was administered. In the operating room, standard monitors were attached, and two wide-bore intravenous cannulas (18G) were secured. She had a heart rate of 90 beats per minute, blood pressure 106/50 mmHg and oxygen saturation (SpO2) 97% on room air. Under aseptic precautions, the 18G Tuohy needle was introduced at L2–L3 space with the patient sitting. The loss of resistance was noted at 4 cm, and a 27G Whitacre needle was used for subarachnoid block with 7.5 mg hyperbaric bupivacaine and 10 µg fentanyl, achieving a sensory level till T6 dermatome. The epidural catheter was secured at 10 cm. A healthy baby was delivered with a satisfactory Apgar score. Intraoperatively, 800 ml crystalloids and 20 units of oxytocin were infused over 2 h. She remained haemodynamically stable without vasopressor support, with 600 ml blood loss during the 75-min surgery. Postoperatively, she received 6 ml of 0.125% bupivacaine with 3 mg morphine through the epidural catheter. She was monitored for the next 24 h and was haemodynamically stable. A significant increase in blood volume, heart rate and cardiac output during pregnancy, labour and postpartum can worsen aorto-cardiac shunt-related complications. Therefore, our goals of anaesthesia were to carefully manage the preload and afterload, prevent bradycardia, avoid beta blockers and minimise shunt fraction by avoiding an increase in systemic vascular resistance (SVR). CSE anaesthesia was chosen because it combines the faster onset of the subarachnoid block with epidural prolongation of intraoperative sensorimotor blockade when necessary.[4,5] A low-dose spinal anaesthesia was administered in CSE to mitigate the haemodynamic effects associated with the conventional dose.[6] Graded epidural was not preferred in our patient due to the emergent nature of the surgery. CSE mitigates adverse effects linked to general anaesthesia, such as myocardial depression, decreased venous return and increased SVR during intubation and extubation, which could precipitate a sudden rise in shunt flow.[2,4] It also allows for postoperative analgesia via an epidural catheter to counter increased SVR associated with pain. In conclusion, combined spinal–epidural anaesthesia stands as a beneficial alternative to epidural anaesthesia and general anaesthesia for emergency caesarean sections in a parturient with ruptured sinus of Valsalva aneurysm. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient consented to her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.