Severe aortic stenosis and subarachnoid hemorrhage: Anesthetic management of lethal combination
A 50-year-old female patient, a known case of severe AS, presented to us with complaints of acute onset severe headache with nausea and vomiting for 2 days. She had history of marked limitation of physical activities and shortness of breath even on mild routine activity. Clinically, she had no neurological deficit. Heart rate was 70/min and noninvasive blood pressure was 168/70 mmHg. On auscultation, she had a pansystolic murmur in aortic area. Computed tomography (CT) scan [] and CT angiography [] of head showed SAH (Fisher grade 2) with lobulated, saccular anterior communicating artery aneurysm. Electrocardiogram suggested left ventricular (LV) hypertrophy. Transthoracic echocardiography revealed stenotic, calcified, bicuspid aortic valve with area of 0.7 cm2, increased pressure gradient (PG) across aortic valve [] (mean PG 45 mmHg and peak PG 74 mmHg), concentric LV hypertrophy and good LV systolic function. Complete blood count, liver function, renal function, and coagulation profile tests were normal except hypokalemia (2.9 mEq/L). In that clinical scenario, patient was planned for emergency neurovascular intervention. Patient was classified as American Society of Anesthesiologists IIIE and accepted for anesthesia and procedure with high-risk informed consent from the patient and relatives.\nAfter all the preparations, patient was shifted to cerebral digital subtraction angiography (DSA) lab. An intravenous line with normal saline was secured through 14G cannula under local anesthesia (LA). A total of 1.2 g of amoxicillin clavulanate was given intravenously for prophylaxis against infective endocarditis (IE). Monitoring with noninvasive blood pressure, continuous electrocardiography, and pulse oximetry was started. Left radial artery was cannulated with 20G arterial cannula under LA. Central venous pressure (CVP) line was placed with ultrasonography guidance in right internal jugular vein under LA. Continuous invasive hemodynamic monitoring was started. Baseline CVP was 5 mm Hg. Intermittent pneumatic pressure above knee stockings were applied over lower limbs. Esmolol and norepinephrine infusions were kept ready.\nPatient was adequately preoxygenated with 100% oxygen. Anesthesia was induced with intravenous etomidate (10 mg) and fentanyl (50 + 25 mcg), followed by vecuronium (6 mg) and lignocaine hydrochloride 2% (4 mL). Gentle direct laryngoscopy and endotracheal intubation was done with endotracheal tube of internal diameter 7.5 mm. Patient was put on volume- controlled ventilation and minute ventilation was adjusted for normocapnia. Anesthesia was maintained with sevoflurane, oxygen in air, and vecuronium. Fentanyl was administered in boluses and titrated according to hemodynamic response. Baseline activated clotting time (ACT) was 159 s. Total of 6000 units of heparin was used for a target ACT of 250-300 s. Potassium chloride was supplemented at 20 mEq/h through central venous line. Intravenous esmolol infusion was started after bolus injection of 25 mg and titrated for heart rate and mean arterial blood pressure. DSA and anterior communicating artery aneurysm coiling lasted for 3 h. Esmolol infusion was titrated from 150-300 mg/h for heart rate from 68 to 77/min and mean arterial pressure from 74 to 80 mmHg. A total of 1 g of intravenous paracetamol was administered toward the completion of procedure. Heparin was neutralized with 60 mg of protamine. At the end of the procedure, patient was shifted to the intensive care unit (ICU) for further management. Neuromuscular blockade was reversed with neostigmine and glycopyrrolate and trachea was smoothly extubated. For the next 4 days, patient was kept in the ICU for cardiac and neurological monitoring. She was discharged from the hospital on 12th day of admission with advice for early aortic valve replacement (AVR).