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, Label 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maneuver, after the transverse colon and omentum have been carefully packed away and the right lobe of the liver has been retracted gently.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 anterior and posterior 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.
Usually, the principal adrenal vein is first identified and then doubly ligated with 00 silk (figure 6). The surgeon then cautiously works about the medial and inferior edges of the gland and ligates the principal artery or accessory arteries in a similar manner. The many minor vessels encountered must also be either carefully ligated or secured with clips.
The approach to the left adrenal via the transabdominal route may take either of two courses, as demonstrated in figures 7 to 10. The usual approach is shown in cross section in figures 7 and 8. The abdominal contents are carefully packed toward the surgeon and then, carefully grasping the spleen, the surgeon divides the avascular splenorenal ligament so that the spleen is mobilized somewhat toward himself or herself. With blunt dissection, it is then possible to dissect above Gerota’s fascia but beneath the pancreas and primary splenic artery and vein. This dissection may be carried medially as far as the superior mesenteric vein, which will give a degree of mobilization as shown in figure 11. The surgeon then incises Gerota’s fascia over the left kidney (figure 8) and, with blunt dissection, clears the superior pole of the left kidney and comes upon the adrenal, which is shown here in a somewhat medial and inferior location. The left lobe of the liver is also identified, but it is usually not necessary to mobilize or retract it. The same general principles of exposure apply to the left adrenal gland except that the prominent adrenal vein (figure 11) is shown being secured first. The surgeon then works about the periphery of the gland, ligating all prominent vessels. This is often slow, meticulous work, but—if in doubt—it is safer to ligate or clip each suspicious vascular area.
Many surgeons have found it useful to approach the left adrenal through the transverse mesocolon, after mobilizing the inferior border of the body and tail of the pancreas (figure 9). This is accomplished by first removing most of the greater omentum from its attachment along the transverse mesocolon and carefully securing any bleeding points in this generally avascular area. Care must be taken to preserve the middle colic vessels, since the omentum is sometimes closely blended with the mesocolon, and these vessels therefore are susceptible to damage during the procedure. An incision is then made along the distal or inferior margin of the pancreas from the tip of its tail, back along the body to the region of the inferior mesenteric vein (danger point [central arrow], figure 9). This allows the surgeon to mobilize the distal pancreas with blunt finger dissection so that it may be elevated in a cephalad manner and to expose Gerota’s fascia directly over the left kidney, whose midportion is usually directly encountered by this approach. This fascia is then incised and the dissection carried about the superior pole of the kidney, where the adrenal can be identified (figure 12). Its lateral edge is then approached and its removal performed as in the procedure described above.