Anesthetic management for craniotomy in a patient with massive cerebellar infarction and severe aortic stenosis: a case report

Abstract

Severe aortic stenosis combined with coronary heart disease remarkably increases the risk of perioperative morbidity and mortality during noncardiac surgery. Surgery and anesthesia often complicate the perioperative outcome if adequate monitoring and proper care are not taken. Therefore, understanding of the hemodynamic changes and anesthetic implications is an important for successful perioperative outcome. This report described the anesthetic management of a patient with a massive cerebellar infarction who was diagnosed with severe aortic stenosis combined with moderate aortic insufficiency and coronary heart disease and hypertension. He was prepared for aortic valve replacement and coronary bypass operation before massive cerebellar infarction occurred. And he received decompressive craniotomy and external ventricular drainage in the prone position under general anesthesia with endotracheal intubation.

Introduction

Severe aortic stenosis (AS) combined with coronary heart disease can increase the risk for anesthesia and has been considered as important risk factor for development of cardiac complications in patients undergoing noncardiac surgery [1]. Perioperative mortality for patients with severe AS is as high as 13% in the 1970s [2]. Sawhney et al reported of the anesthetic management of a patient with AS who underwent craniotomy for excision of the tumor after undergoing prophylactic Balloon aortic valvuloplasty (PBAV) [3]. This is a case report of the anesthetic management of a patient with severe AS combined with moderate aortic insufficiency (AI) and Coronary heart disease who had a massive cerebellar infarction. He underwent decompressive craniotomy and external ventricular drainage in the prone position under general anesthesia. Written informed consent was obtained before preparation and submission of this manuscript.

Case report

A 57-year-old man with a massive cerebellar infarction presented for emergency surgery with a 3-days of coma prior to admission. He was prepared for aortic valve replacement and coronary bypass operation because he was diagnosed with severe AS and moderate AI and coronary heart disease before massive cerebellar infarction occurred to him.

The patient has received endotracheal intubation and mechanical ventilation before he was sent to the operating room. His heart rate was 89 beats/min and blood pressure was 170/85 mm Hg. There was an ejection systolic murmur (grade 3/6) in the aortic area with radiation to neck. Breath sounds were harshness during auscultation. Results of routine hematologic showed WBC was very high 26.19×10⁹ and biochemical investigations were within normal limits. Doppler echocardiography showed that severe AS coexisted with moderate aortic insufficiency, the area of aortic was 0.9 cm² and systolic aortic valve gradient of 86 mmHg with concentric left ventricular hypertrophy. The ejection fraction was 54%. Coronary artery computed tomography (CT) found that coronary atherosclerosis, anterior descending artery in 10%, left circumflex stenosis in 85%, 60%-70% right coronary artery stenosis. Valvular heart disease, aortic valve disease, the ascending aorta widened. Brain CT showed large area cerebral infarction of cerebellum and hydrocephalus.

Since this patient was to undergo decompressive craniotomy and external ventricular drainage in the prone position, it was thought that he had a high risk for developing disastrous intraoperative and postoperative cardiac complications with more difficulty for urgent rescue. As there was severe AS combined with moderate insufficiency, and massive cerebellar infarction with brain hernia information, aortic valve replacement or palliative BAV could not be performed prior to emergency surgery. Preinduction vital signs included a heart rate of 89 beats/min and right arm blood pressure of 156/76 mm Hg. The patient has been inserted of a three-lumen central venous catheter and a left radial artery catheter for arterial pressure monitoring before he entered operating room. Perioperative monitoring included electrocardiography II and V5, direct arterial pressures, pulse oximetry, end-tidal CO₂ pressure, central venous pressure, temperature, arterial blood gas levels, urine output and hemodynamic data. Etomidate (0.3 mg/kg), sufentanil (1 μg/kg) and rocuronium (0.6 mg/kg) were administered for anesthesia induction [4,5]. Then we changed the intubation catheter with reinforced tracheal tube for prone position and controlled ventilation was instituted to maintain an end-tidal CO₂ pressure in the range of 32 to 40 mm Hg. Anesthesia was maintained with O₂ and air (FiO₂, 0.5), sevoflurane (1%~2%) and remifentanil (0.1~0.2 μg/kg/min) continuous pump infusion. Intraoperative recording bispectral index (BIS) was used to monitor the depth of anesthesia [6-8].

Soon after the patient changed to prone position, he developed high airway pressure to 32 cm H₂O. Then we checked the ventilation tube and given sputum suction. And airway pressure recovered to 15~20 cm H₂O. The blood pressure decreased to 105/70 mmHg during sterilization, then phenylephrine 40 ug was given and the BP did not respond well. So small dose of dopamine infusion (5 μg/kg/min) was started and BP was maintained about 120~130/70~80 mmHg. CVP was 14~16 cm H₂O during operation by appropriate volume supplement of crystolloid and colloid. The rest of the surgery was uneventful, and there were no further hemodynamic or respiratory disturbances.

Surgery lasted 4 hours, and the blood loss was about 400 mL with a urine output of 1,200 mL. The patient received 1.5 L of Ringers solution, 500 mL of Gelofusion, and 1 unit of packed red blood cells. And he was later transferred to the intensive care unit after he received tracheotomy. He continued to receive mechanical ventilation for 2 days after surgery. The vital signs remained stable, and he was discharged 25 days after operation.

Discussion

Patients with severe AS combined with coronary heart diseases undergo noncardiac surgery have always been considered to be a high-risk group for perioperative cardiac morbidity. Goldman et al found 13% (3/23 patients) cardiac mortality among patients with AS for noncardiac surgery [2]. At Erasmus Medical Center in The Netherlands between 1991 and 2000, cardiac complications (cardiac death or nonfatal myocardial infarction within 30 days of surgery) occurred in 15/108 (14%) patients with AS, with the majority of these complications being cardiac death [9]. Several recent studies demonstrate lower perioperative mortality for AS patients. The Mayo Clinic reported that no intraoperative events, but 11% major postoperative events happened among 19 patients with severe AS [10,11]. Another recent study showed that no severe cardiac events happened in 30 patients with asymptomatic severe AS underwent low or intermediate-risk noncardiac surgery [10]. However, most of these operations were short time and simple surgery such as diagnostic procedures. To our knowledge, no reports of patients with severe AS combined with AI undergoing decompressive craniotomy procedures for massive cerebellar infarction.

There is a significant association between cardiac disease and ischemic stroke. Preexisting cardiac disease or cardiac dysfunction is related to the acute neurohumoral and autonomic stress response to stroke [12-18]. And the patient we reported in this case was a topical example for this situation. He was diagnosed with severe AS and moderate AI combined with coronary disease before he suffered massive cerebellar infarction. Even though he was treated by pharmacological therapy for heart surgery, the severe stroke occurred to him preoperatively by unknown reason.

Recent studies suggested that decompressive craniectomy could improve outcome in patients with malignant infarction after stroke [19]. However, the cardiac risk during and after acute stroke have been reported higher than other noncardiac surgery. Decompressive craniectomy involves emergency surgery in patients with severe stroke have been identified as risk factors for perioperative cardiac events. Durga et al reported that the incidence of Serious cardiac adverse events after decompressive craniectomy for stroke was 47.6% and the mortality in patients with Serious cardiac adverse events was 75% [20].

In this patient, who was diagnosed with severe AS coexisted with moderate AI and coronary diseases, hypertension and was prepared for aortic valve replacement and coronary bypass operation. During the period of preparing for the heart surgery, the patient received careful cardiac examination and medical treatment for hemodynamic balance. Because the complicated heart valve and coronary diseases coexisted, he could not receive any cardiac invasive treatment before decompressive craniotomy surgery. Even though the patient received dehydrated therapy with mannitol and furosemidum, the blood pressure was still 156/76 mmHg when he entered the operating room. Anesthesia was performed with etomidate to avoid hypotention during induction. And we chose sufentanil as analgesia agent which has strong analgesia effects and little influence on hemodynamics.

The key factor for the anesthesia maintenance in patients with severe AS and AI is to maintain myocardial oxygen supply and demand balance. Heart rate was kept between 70 and 80 beats per minute in patient who suffer severe AS coexisted AI, β-blockers such as esmolol can be continuously pumped to maintain appropriate HR. CVP was maintained 14 and 16 cm H₂O, which assured an appropriate intravascular volume status and avoided cardiac ischemia. Phenylephrine and small dose of dopamine were used to treat hypotension.

When moving the patient into the prone position, airway pressure changed to 32 cm H₂O suddenly and a large amount of secretion and sputum was extracted and then the airway pressure recovered to 15 and 20 cm H₂O. We reviewed the case report and found that the patients suffered pulmonary infection after coma. So sputum blocked the trachea after he was changed to prone position. Meanwhile, clinical studies found that decrease in cardiac index (CI) when surgical patient is in prone postion [21-32]. So we put a defibrillator in stand-by mode near the operation table.

The patient experienced preparing for heart surgery before stroke and his left ventricular function was improved with medical treatment. Normal heart function as well as careful anesthesia management may have contributed to a satisfactory outcome in our patient undergoing decompressive craniotomy. Meanwhile, carefully operation procedures and less blood loss were important for the patient surviving the surgery. In conclusion, there was high risk with severe AS and AI with coronary heart disease for the patient undergoing decompressive craniotomy for massive cerebellar infarction in prone position, and he could not be performed PBAV for combined AI, but he survived perioperative period with careful administration of anesthesia along with appropriate monitoring. It suggested that improved ventricular function is very important for noncardiac surgery with severe AS and other heart diseases. Patients with more complicated heart valve diseases may need prior correction or invasive treatment of the underlying cardiac injury.

Disclosure of conflict of interest

None.