Technology, Computing, and Simulation: General Articles: Case Report
Most radiologic procedures are diagnostic. However, technologic advances in radiology have led to a rapidly evolving interventional and therapeutic practice. The most commonly performed procedures requiring anesthesia outside of the operating room are diagnostic studies and interventional radiologic procedures (1). Anesthesiologists are often asked to provide anesthetic care for patients undergoing radiofrequency ablation (RFA) of neoplastic lesions (2–4). Although RFA is an effective treatment for a variety of neoplastic lesions (2,3), it is not without risk. Injury to adjacent normal tissue is a major concern during RFA of cancerous lesions. Bowel perforation, cholecystitis, bile duct stricture, and portal vein thrombosis have been reported (4–6). Severe hypertensive crisis due to unintended injury to the adrenal gland during RFA of primary and metastatic liver tumors has also been described (7). Hypertensive crisis during RFA of adrenal masses has not been reported. We report a case of hypertensive crisis with associated tachycardia and ventricular arrhythmia during RFA of renal cell carcinoma metastatic to the adrenal gland.
An 82-yr-old, 80-kg woman with no history of hypertension presented with renal cell carcinoma metastatic to the right adrenal gland. Computed tomography revealed a 2.6 × 2.7-cm renal mass, consistent with renal cell carcinoma, and a 2.6 × 2.8-cm partially necrotic right adrenal mass. She was scheduled to undergo percutaneous RFA of the renal and adrenal masses. Her medical history was remarkable for clear cell renal cell carcinoma, transitional cell carcinoma of the bladder, adenocarcinoma of the breast, and hyperlipidemia. Her only medication was atorvastatin. The patient reported good exercise tolerance, without symptoms of ischemic heart disease. Her airway, lung, heart, and neurologic examinations were unremarkable. She was afebrile, with an arterial blood pressure of 150/68 mm Hg and a heart rate of 68 bpm. Preoperative electrocardiogram (ECG) showed a normal sinus rhythm with a heart rate of 70 bpm. Endocrinology consultation was performed before the procedure, and this confirmed a nonfunctioning mass of the right adrenal gland.
After placement of standard ASA monitors (pulse oximeter, ECG, and noninvasive arterial blood pressure cuff) and establishment of peripheral venous access, anesthesia was induced with IV lidocaine (40 mg), fentanyl (50 μg), and propofol (120 mg). Muscle relaxation was achieved with succinylcholine (120 mg). The patient was tracheally intubated without difficulty, and anesthesia was maintained with inhaled isoflurane (0.5%–1.2%), nitrous oxide (70%), and oxygen (30%). Her arterial blood pressure was measured in the left upper extremity every 3 min. The patient remained hemodynamically stable throughout the induction of anesthesia and during RFA of the right renal mass. Shortly after initiation of ablation of the right adrenal mass, severe hypertension was noted (249/140 mm Hg). Concomitantly, her ECG showed a narrow complex tachycardia (140 bpm) with frequent multifocal premature ventricular contractions (Fig. 1). Ablation was suspended, and her increased arterial blood pressure and heart rate were treated with incremental doses of esmolol (100 mg total; 1.25 mg/kg). Sodium nitroprusside was not immediately available during this hypertensive episode. Her heart rate and rhythm and her blood pressure returned to baseline levels 5 min after esmolol administration and suspension of ablation. Because of the curative nature of the procedure, the final ablation attempt of the adrenal mass commenced and was associated with a similar hypertensive response that was successfully treated with esmolol (50 mg). The procedure concluded, and the patient was tracheally extubated and taken to the postanesthesia care unit. In the postanesthesia care unit, the patient remained hemodynamically stable. There was no evidence of neurologic, cardiac, or pulmonary complications during recovery or on subsequent follow-up.
Image-guided radiologic procedures involving the adrenal gland are less invasive and, theoretically, less stimulating than surgical procedures. Patients undergoing RFA typically have an electrode placed percutaneously into a tumor under image guidance. The electrode is connected to a generator that produces an alternating current and results in ionic agitation in the tissue and frictional heat. At temperatures of 60°C, instant cell death occurs because of protein denaturation.
Mayo-Smith and Dupuy (8) reported no intraoperative complications in 12 patients who underwent 13 RFA procedures of the adrenal gland. However, RFA can cause severe hemodynamic consequences. Onik et al. (7) described life-threatening hypertensive crises in two patients undergoing hepatic RFA. Onik et al. suggested that ablation of tumors located in the posterior right lobe of the liver can cause unintended heating of and injury to the adrenal gland, leading to catecholamine release and subsequent hemodynamic effects. One of the patients in the report by Onik et al. had catecholamine concentrations measured during RFA that were 10 times larger than normal.
Open and laparoscopic adrenalectomy for nonsecreting adrenal tumors is rarely associated with severe intraoperative hypertension. Ligation of the adrenal vein is typically performed after surgical exposure of the adrenal gland is achieved. Ligation of the adrenal vein will prevent the release of catecholamines into the systemic circulation should injury to normal adrenal tissue occur. In contrast, ligation of the adrenal vein is not performed during RFA of adrenal tumors.
The hypertensive crisis in our patient was likely related to injury of normal adrenal tissue in or near the adrenal mass being ablated, causing the release of catecholamines into the circulation. Catecholamine surge can lead to tachycardia, cardiac arrhythmias, and rapid increases in afterload, resulting in cardiac ischemia, diastolic dysfunction, ventricular failure, and pulmonary edema. In addition to cardiac damage, acute hypertensive crisis can lead to central nervous system sequelae such as hemorrhagic stroke (9). The optimal treatment of catecholamine-induced hypertensive crises during anesthesia is not known. According to Groudine et al. (9), direct-acting vasodilators may be the treatment of choice. Long-acting β-blockers can potentially precipitate cardiac failure during this situation and should be avoided. Esmolol may be a good choice for treating tachycardia that develops during catecholamine surge. The effectiveness of a preoperative regimen consisting of an α1-adrenergic antagonist followed by a β1-adrenergic antagonist for preventing the sequelae of catecholamine surge in patients with metastatic nonsecreting adrenal masses undergoing RFA is not known.
In conclusion, experience with RFA of adrenal tumors is limited. The sudden severe hypertension, tachycardia, and ventricular irritability seen in our patient were probably caused by massive catecholamine release into the circulation as a result of heating and subsequent injury to normal adrenal tissue. The adrenal vein is not separated from the systemic circulation during RFA of adrenal masses, thus allowing the catecholamine surge to reach the systemic circulation. Clear information identifying whether adrenal masses targeted for RFA contain functional adrenal tissue is frequently not available. We suggest direct measurement of arterial blood pressure in addition to routine ASA monitoring when providing anesthetic care for patients scheduled for RFA of adrenal lesions. Direct-acting vasodilators and short-acting β1-adrenergic antagonists and a means to administer these medications (infusion pumps) should be readily available when delivering anesthesia in remote locations. Identifying normal functional adrenal tissue in or around adrenal masses to be ablated should increase awareness of the potential for catecholamine surge during RFA. Careful planning and discussion with the radiologist about the possibility for catecholamine surge should help to reduce the incidence and severity of these complications.
1. Gallagher TJ. Anesthesia outside the operating room. In: Stoelting RK, Barash PG, Gallagher TJ, eds. Advances in anesthesia. Vol. 4. Chicago: Year Book Medical Publishers, 1987:25–46.
2. Curley S, Izzo F, Delrio P, et al. Radiofrequency ablation of unresectable primary and metastatic hepatic malignancies. Ann Surg 1999;230:1–8.
3. Curley S, Izzo F, Ellis L, et al. Radiofrequency ablation of hepatocellular cancer in 110 patients with cirrhosis. Ann Surg 2000;232:381–91.
4. Solbiati L, Oerace T, Tonolini M, et al. Radiofrequency thermal ablation of hepatic metastases. Eur J Ultrasound 2001;13:149–58.
5. Goldberg SN. Radiofrequency tumor ablation: principles and techniques. Eur J Ultrasound 2001;13:129–47.
6. Llovet J, Vilana R, Bru C, et al. Increased risk of tumor seeding after percutaneous radiofrequency ablation for single hepatocellular carcinoma. Hepatology 2001;33:1124–9.
7. Onik G, Onik C, Medary I, et al. Life-threatening hypertensive crises in two patients undergoing hepatic radiofrequency ablation. AJR Am J Roentgenol 2003;181:495–7.
8. Mayo-Smith WW, Dupuy DE. Adrenal neoplasms: CT-guided radiofrequency ablation—preliminary results. Radiology 2004;231:225–30.
9. Groudine SB, Hollinger I, Jones J, DeBouno BA. New York State guidelines on the topical use of phenylephrine in the operating room: the Phenylephrine Advisory Committee. Anesthesiology 2000;92:859–64.