Plate 146

The presence of cortical or medullary tumors of either a malignant or benign adenomatous nature is a well-established indication for unilateral adrenalectomy. In recent years, however, the number of indications for bilateral adrenalectomy has gradually increased. It is occasionally performed to control complex endocrine states after partial or unilateral adrenalectomy has failed to alleviate hyperaldosteronism or hypercortisolism, as in Cushing's syndrome.

The most important preoperative procedure is to establish a firm diagnosis. Clinical findings often indicate the altered pathophysiology, but extensive endocrine studies are usually necessary, not only to establish the disorder within the adrenals but also to rule out associated disorders in other endocrine glands. Unless they are malignant, tumors are seldom large enough to be identified by pyelography, tomography, retroperitoneal gas injection, or aortography. Computed tomography scans may be helpful. Accordingly, the reader should refer to current texts on diagnostic endocrinology for the required procedures. When adrenalectomy is decided upon, the surgeon should investigate and, if possible, correct many of the secondary systemic and metabolic effects that are the direct result of the altered functional activity of the adrenal. The management of the hypertension and its cardiovascular sequelae is a major problem with pheochromocytomas. Problems associated with hypercorticolism include hypokalemia with alkalosis, hypertension, polycythemia, musculoskeletal depletion with osteoporosis and hypercalcemia, abnormal glucose tolerance, multiple areas of skin furunculosis, and, finally, poor wound healing. Thus, the surgeon must be aware that many organ systems and their responses to surgery are profoundly affected by adrenal malfunction.

Preoperative consultation and communication among endocrinologist, surgeon, and anesthesiologist are necessary. The anesthesiologist must be prepared for adequate blood and endocrine replacement and occasionally for a prolonged procedure that may be extended into the chest. Electrolytes should be in optimum condition and the patient prepared with parenteral cortisone the evening before and on the morning of surgery for hypercorticolism or bilateral adrenalectomy. Adequate blood must be available, as hypertension plus increased vascularity and fragile veins about the adrenals all tend to increase blood losses.

General anesthesia with endotracheal intubation is preferred. Patients with pheochromocytomas should have adequate preoperative preparation with a long-acting adrenergic (alpha receptor) blocking agent, such as phenoxybenzamine hydrochloride (Dibenzyline). To minimize wide fluctuations of blood pressure, an intra-arterial line should be placed and hypertension controlled with an intravenous infusion of sodium nitroprusside (Nipride). After assuring that adequate fluid and blood replacement has been accomplished, an infusion of norepinephrine (Levophed) may be necessary to treat hypotension. Propranolol hydrochloride (Inderal) and lidocaine hydrochloride (Xylocaine) may be needed to control tachycardia and cardiac arrhythmias. Once the tumor is out, norepinephrine may be needed for several days with gradual tapering as tolerated.

The patient is placed supine with the foot of the table slightly down, so that moderate hyperextension can be obtained if necessary. A posterior approach to the adrenals can be used but is not described here. This approach may be used for the ablation of normal-size adrenal glands.

The patient's hair should be completely removed with minimal trauma to the skin. In the anterior approach, the skin of the lower chest and abdomen well into the flanks should be included in the preparation, since, in making a transverse incision, it may be necessary to go far into the flanks in obese patients.

The surgeon stands on the patient's right side and outlines an incision about two to three fingerbreadths below the costal margin with its apex about two fingers below the tip of the xiphoid process (Figure 1). A thoracoabdominal approach through the ninth interspace may be used for large adrenal tumors occurring on the right side. When the posterior approach is used, the incision extends from the level between the 11th and 12th ribs 5 cm from the midline and curved downward to the midportion of the ileum. Increased vascularity in the subcutaneous tissue is common in these cases, particularly in Cushing's syndrome. Thus meticulous ligation of all bleeding points or control with electrocoagulation should be carried out before the peritoneal cavity is opened. Both rectus muscles are divided, and then the transversus muscle and peritoneum are incised through a liberal incision. This is necessary since many of these patients tend to be obese. Additional exposure may be obtained by dividing the internal oblique muscles in the direction of their fibers out into the flanks. The falciform ligament to the liver is divided between curved hemostats and then ligated. In some patients it may be prudent to mobilize the right lobe of the liver by dividing the falciform and right triangular ligaments (Plate 110).

The surgeon must first be aware of the anatomic differences of the two adrenal glands (Figure 2). The right adrenal is close to the superior pole of the kidney, the vena cava medially, and the right lobe of the liver superiorly. Its main arterial supply comes directly to its medial edge from the aorta (Figures 2, 11), and the main right adrenal vein (5) comes directly from the inferior vena cava in a parallel manner. In contrast, the left adrenal is in proximity to the aorta medially, the renal vein inferiorly, and the superior pole of the left kidney. Its main arterial supply comes directly from the aorta (12), but the main left adrenal vein (6) usually comes from the left renal vein (8). Both adrenal glands, however, have many arterial twigs from both the inferior phrenic arteries (9 and 10) and both renal arteries.

The operative exposure of the right adrenal is shown first (Figure 3); it is begun with a classic Kocher maneuver, after the transverse colon and omentum have been carefully packed away and the right lobe of the liver has been retracted gently. The right lobe of the liver should be fully mobilized to gain a better exposure of the right adrenal. After the peritoneum lateral to the duodenum has been incised, it is mobilized in the usual manner by blunt dissection with the surgeon's index finger under the head of the pancreas. The inferior vena cava is exposed in its position directly posterior to the second portion of the duodenum (Figure 4) and then cleared to show the right renal vein. The superior pole of the right kidney is located and exposed with further blunt finger dissection. The adrenal is identified by its characteristic yellowish color, lobulated appearance, and clearly definable blunt lateral edge. This generally avascular area is then incised (Figure 5), and additional exposure and mobility of the adrenal gland may be obtained by gentle blunt finger dissection directly posterior to the gland. The surgeon should bear in mind that the vascular attachments are usually on or near the medial and superior edges of the gland rather than on its broad surfaces. If preoperative studies show a large adrenal tumor, especially on the right side, a thoracoabdominal incision should be considered in order to provide exposure for mobilizing the right lobe of the liver. It may be necessary to remove the kidney along with the invading adrenal neoplasm.

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