Chapter 63. Adrenalectomy

The adrenal, or suprarenal, glands are paired retroperitoneal organs positioned superomedial to the kidneys at the level of the 12th rib. Each gland is divided into an outer cortex and an inner medulla, which are histologically and functionally distinct layers derived from separate embryologic tissues. The cortex originates from ectoderm and is composed of three zones that produce steroid hormones: the zona fasciculata, which produces mineralocorticoids; the zona glomerulosa, which produces glucocorticoids; and the zona reticularis, which produces sex hormones. The medulla is derived from neural crest cells and is composed of modified postganglionic neurons that connect with the sympathetic nervous system in order to produce epinephrine, norepinephrine, and dopamine in response to sympathetic stimuli.

The arterial supply to the adrenals originates from the inferior phrenic arteries, aorta, and renal arteries. Although the anatomy is quite variable, the majority of the arterial supply approaches from the medial and inferior borders of the adrenal glands with few substantial arteries from the superior, posterior, or lateral sides. The adrenal arteries are generally small and amenable to electrocautery. Conversely, the venous anatomy to the adrenal gland is more consistent; usually there is a single large draining vein of substantial size that requires ligation. The right adrenal vein length tends to be short and it drains directly into the inferior vena cava (IVC). In contrast, the left adrenal vein is usually of generous length and drains into either the left renal vein or the inferior phrenic vein. Ligation of the left inferior phrenic vein is of no significant physiologic consequence. The adrenal gland is surrounded by variable amounts of fat, which is loosely attached posteriorly to diaphragmatic muscle. This surrounding fat can obscure the visualization and identification of adrenal tumors. Left-sided adrenal tumors can be adjacent to the spleen, pancreas tail, liver, kidney, or renal hilum. Right-sided adrenal tumors can be adjacent to the liver or IVC. Invasive adrenal tumors can extend into these surrounding structures.

Aldosteronoma

Aldosteronomas are cortical adrenal tumors that autonomously secrete aldosterone. Hyperaldosteronism was first described by Jerome Conn in 1955 and is characterized by hypertension and hypokalemia.1 These symptoms should be controlled preoperatively with an aldosterone antagonist and potassium supplements. Biochemical confirmation of autonomous hypersecretion of aldosterone should be confirmed prior to adrenalectomy. This is best achieved by salt loading followed by a 24-hour urine collection of aldosterone, sodium, and creatinine. Aldosterone antagonists should be held prior to testing for at least a few weeks. While there are several forms of primary hyperaldosteronism, surgery is indicated only in the setting of unilateral adrenal adenoma or hyperplasia. Because aldosteronomas are almost always benign tumors, a cortex-sparing nodulectomy can be performed when the tumor is peripheral; however, this approach has a higher risk of persistent hyperaldosteronism.

Since benign, nonfunctional adrenal tumors are common relative to the incidence of hyperaldosteronism, selective venous sampling should be used to confirm laterality of disease in patients who are older than 40 years. Although many surgeons believe that computerized tomography (CT)2 or magnetic resonance imaging (MRI) is sufficient when unilateral disease is identified in younger patients, it is our practice to perform selective venous sampling for all patients who are considered candidates for adrenalectomy. This is supported by a recent study that found that 50% of patients in their primary hyperaldosteronoma cohort would have been inappropriately managed based on preoperative CT findings alone.3

Postoperatively, normalization of aldosterone levels confirms surgical cure and is typically associated with correction of hypokalemia. Infrequently, hyperkalemia can result from chronic suppression of the contralateral adrenal gland. With complete resection of the aldosteronoma, nearly all patients have normal serum potassium levels and hypertension is improved in most. Persistent hypertension after curative adrenalectomy is usually due to underlying essential hypertension.

Pheochromocytoma

Pheochromocytomas are rare neuroendocrine tumors that are derived from chromaffin cells and usually arise from the adrenal medulla. Although most pheochromocytomas are sporadic and unilateral, genetic syndromes, such as multiple endocrine neoplasia 2 and von Hippel-Lindau disease, increase the risk of bilateral disease. Pheochromocytomas can produce catecholamines such as epinephrine, norepinephrine, and dopamine that can cause the classic clinical symptomatology of this disease: episodic headaches, palpitations, and diaphoresis. Rarely, pheochromocytomas are nonfunctional. Preoperative preparation with alpha-blockade (eg, phenoxybenzamine, doxazosin) and salt loading should be undertaken. Ideally, this can be done in the outpatient setting. The alpha-blocker is titrated up to the maximal tolerated dose, which is typically limited by orthostatic hypotension. In addition, beta-blockade can be added to the regimen if the patient has persistent tachyarrhythmias. Although the optimal preparation time before pheochromocytoma resection is controversial, we generally alpha-block and salt-load our patients for 1–2 weeks before elective adrenalectomy.

The first successful resection of a pheochromocytoma was performed by César Roux in Switzerland in 1926 and shortly thereafter by Charles Mayo in the United States. Delicate tissue handling and avoidance of tumor compression should be emphasized to minimize catecholamine release. Because tumor manipulation and adrenal vein clipping can result in significant hemodynamic changes, coordination and communication between the adrenal surgeon and anesthesiologist are critical to the success of this operation. Because of the risk of catecholamine surges during tumor manipulation, many propose early identification and clipping of the adrenal vein. After dividing the adrenal vein, we grab the tumor side of the divided vessel to use as a handle for retraction. However, some caution that adrenal vein ligation increases intratumoral venous pressure, which can increase bleeding.4 Regardless, if the vein is ligated early or late in the dissection, communication between the surgical and anesthesia teams is necessary, because hypotension is often recognized after vein ligation.

Endoscopic adrenalectomy is the favored procedure when there is no evidence of malignant disease.5 A randomized controlled trial of laparoscopic versus open adrenalectomy for pheochromocytoma found no significant differences in hemodynamic instability between the two groups, but operative time and blood loss were favored in the laparoscopic group.6 Although laparoscopic or retroperitoneoscopic resection is favored for small and noninvasive tumors, conversion to the open approach should be considered whenever there is difficulty achieving gross tumor clearance. Conversion to open surgery is appropriate if capsular disruption seems imminent during endoscopic dissection.

Cortisol-Producing Adrenal Adenoma

Adrenal adenomas that produce cortisol can be incidentally discovered during abdominal imaging or when the patient develops the signs and symptoms of Cushing's syndrome. In the early 1930s, Harvey Cushing was among the first to describe the clinical entity of hypercortisolism, which is characterized by truncal obesity, round face, fragile skin, depression, and abdominal striae. These tumors autonomously secrete cortisol without the usual dependence on adrenocorticotrophic hormone (ACTH) and can increase the risk of cardiovascular complications and mortality.

Because adrenocortical carcinomas (ACCs) also frequently secrete cortisol, a careful preoperative evaluation should be performed to look for signs of malignancy, such as radiographic evidence of local invasion, regional lymphadenopathy, distal metastases, and rapid growth. Small tumor size and well-defined borders are predictive of benign cortisol-producing adenomas. Because the risk of ACC increases with larger tumor size, patients should be considered for open resection if the tumor size exceeds 6 cm.7–9

Postoperatively, adrenal function may be suppressed in the contralateral gland, and patients should be given a prophylactic hydrocortisone taper to avoid potential postoperative adrenal insufficiency. The steroid taper can progress according to patient symptoms and can be monitored with serum cortisol and ACTH levels drawn in the morning. Because patients with these tumors can have obesity resulting from Cushing's syndrome, they can present an additional technical challenge for laparoscopy. Often, port sites at the skin can dilate during the procedure, resulting gas leakage during the operation. Therefore, it is ideal to make the port site incisions as small as technically possible to avoid gas leakage and loss of operative domain during peritoneal insufflation. Cushing's patients also have a higher risk of postoperative infection, so preoperative prophylactic antibiotics should be used.

Adrenal Cyst

Simple cystic lesions are usually incidental, and surgery is not indicated unless there is a solid component to the cyst wall. Complex cysts with evidence of local invasion should undergo open resection. Large cysts that cause symptoms or that are at high risk of spontaneous rupture can be excised by laparoscopic nodulectomy or subjected to fenestration of the cyst wall into the peritoneal cavity.

Myelolipoma

These lesions are also typically discovered in an incidental manner. Their appearance can cause confusion with liposarcoma, a situation easily resolved with needle biopsy showing typical bone marrow elements. Patients with these benign adrenal lesions are often referred to surgery because of compressive symptoms.

Adrenal Cortical Cancer

Adrenal cortical carcinoma is a rare and aggressive tumor derived from the adrenal cortex. As many as 60% of ACCs in adults autonomously hypersecrete cortisol or sex steroids. Although complete surgical resection is the mainstay of therapy, ACC is often locally invasive, which typically precludes complete extirpation. Local tumor invasion precludes endoscopic resection. Initial reports of laparoscopic adrenalectomy for ACC suggested that the recurrence rates were higher than open resection.8 This was the reason for many to recommend that malignancy was an absolute contraindication for laparoscopic resection of primary adrenal cancers. Recently, several groups have challenged this paradigm and have reported success with laparoscopic resection of malignant adrenal disease.9,10

While this topic remains controversial, we do not attempt minimally invasive adrenalectomy when local invasion is determined on preoperative imaging. Intraoperative difficulty with establishing tissue planes between the adrenal gland and neighboring structures due to tumor extension portends malignancy and should prompt immediate conversion to open adrenalectomy.

Incidentaloma

Incidentalomas are tumors that come to clinical attention through abdominal imaging for some other indication. The clinical relevance of these masses pertains to the concern for malignancy. Small, nonfunctional incidental tumors (<4 cm) do not require resection and are typically benign.11 Biochemical exclusion of pheochromocytoma, aldosteronoma, and hypercortisolism is necessary. Larger lesions (>4 cm) are at higher risk for carcinoma, and open resection should be considered. Although controversial, laparoscopic resection of incidental tumors greater than 4 cm in size can be safely achieved for tumors without gross extension.2 Formal decision analysis of the management of incidentalomas has determined that laparoscopic resection is ideal if the morbidity of surgery is less than 3% and the probability of hypersecretion, tumor growth, or malignancy exceeds 7.5%.12 The former can often be achieved in the hands of an experienced adrenal surgeon and the later is seen in tumors larger than 5 cm.

Paraganglioma

Paragangliomas are neuroendocrine tumors histologically similar to pheochromocytomas but occur in extra-adrenal sites throughout the abdomen, chest, and head. Most of these tumors are sporadic and can present as a painless mass or with the symptomatology of a pheochromocytoma resulting from catecholamine production. There are a several case reports of successful laparoscopic resection of these tumors.13–15 The decision to use this approach should depend on the location and size of the paraganglioma, as well as the surgeon's experience.

Metastasis

Resection of adrenal metastases is controversial and the role for surgical treatment is changing, now that safe minimally invasive resection can be achieved with minimal morbidity. Although no prospective trials have proven that adrenalectomy improves survival, many groups have reported safe laparoscopic resection of various secondary tumors, such as lung, renal cell,16 colon, and melanoma.17,18 For the laparoscopic approach specifically, it is equivalent to open adrenalectomy regarding recurrence and survival and provides the additional benefit of reduced postoperative morbidity.19 Furthermore, there is a role for palliative laparoscopic resection for patients with symptomatic secondary tumors. Attempts at laparoscopic metastasectomy should be avoided in any patient with radiographic evidence of local invasion, as complete resection without capsular disruption is unlikely.

Since the initial report of laparoscopic adrenalectomy in 1992,20 surgical experience has grown along with significant progress in endoscopic technologies. As such, the laparoscopic approach has become the procedure of choice for most adrenal tumors less than 6 cm in size. Retroperitoneoscopic adrenalectomy uses laparoscopic instruments but avoids entrance and insufflation of the peritoneal cavity. This technique involves direct entrance into the retroperitoneal space from the posterior side. Retroperitoneoscopic adrenalectomy is superior to laparoscopic adrenalectomy in selected patients, and there are numerous considerations when considering which surgical approach to use for the resection of adrenal tumors.

Advantages of the Laparoscopic Approach

For most patients who undergo laparoscopic adrenalectomy, the smaller incisions, lower blood loss, and lessened abdominal wall/flank trauma from divided muscles translate into a less painful and more rapid recovery when compared to open adrenalectomy. Median hospital stay is under 3 days for laparoscopic adrenalectomy, versus 7 days or more for the open procedure.21 In addition, one can anticipate a reduction in general morbidity, such as catheter-associated urinary tract infections, pneumonias, and deep venous thrombosis.

One can counter that modern large-incision surgery has improved dramatically with the use of continuous epidural anesthesia, more rapid mobilization, and improvements in operative technique. Nonetheless, incisions for open adrenalectomy are large and morbid: subcostal incisions produce long-term limitation of rectus abdominis function; midline celiotomies result in ileus and a frequent incidence of ventral hernia; and thoracoabdominal incisions can produce pain and muscle denervation syndromes. These long-term issues are avoided almost entirely with the laparoscopic approach.

The laparoscopic approach is particularly advantageous for the patient who is disabled with Cushing's syndrome from an autonomous adrenal adenoma. Patients with this diagnosis have such reduced muscle mass and reduced defense against infection that they become essentially immobilized with an open adrenalectomy. Adrenalectomy in patients with hypercortisolism carries a higher risk of general complications, including wound disruption and infection.

Laparoscopy is also especially advantageous for the patient with Conn's syndrome and a small unilateral peripheral adrenal adenoma. These patients can undergo nodulectomy for their tumors, be discharged from the hospital within 24 hours, and be back to work within days.

It is also technically feasible to perform laparoscopic adrenalectomy through a single laparoscopic port site. This new approach provides the incremental benefit of using a single 2-cm incision, rather than three or four separate laparoscopic ports, for access to the adrenal gland through the peritoneal cavity.22 Because the current experience with single-incision laparoscopy is limited, future studies are needed to determine patient selection criteria.

Disadvantages of the Laparoscopic Approach

Laparoscopy is not appropriate for every patient, and some general contraindications to laparoscopy and transperitoneal resection include severe chronic obstructive pulmonary disease (COPD) (related to the inability to tolerate CO2 insufflation), uncorrectable coagulopathy, dense intra-abdominal adhesions, and widely metastatic disease. There are, however, circumstances in which the adrenal gland must remain unseen—in other words, it must be removed as a radical adrenalectomy with an intact capsule of surrounding perinephric and suprarenal fat. The most common circumstance is that of suspected malignancy, in which breach of the tumor capsule and spillage of cancer cells can compromise postsurgical outcome.

The other circumstance in which a laparoscopic approach might be problematic is in patients who require bilateral adrenalectomy for ACTH-dependent Cushing's syndrome. In these patients, spillage of adrenal cortical cells in the presence of increased levels of their trophic factor, ACTH, risks reimplantation and the adrenal equivalent of splenosis. The authors are aware of such an unfortunate case. This risk is compounded by the absolute necessity to remove all adrenal tissue, a maneuver that is difficult to accomplish with certainty without laparoscopic manipulation and retraction of the adrenal itself. The adrenal gland is so friable in these cases that manipulation usually results in breach of the adrenal.

Another limiting circumstance is morbid obesity. The adrenal can frequently be obscured by surrounding fat. A CT scan will provide an estimate of the amount of fat around the adrenal. Large amounts should dissuade the surgeon from choosing laparoscopy, as there already will be substantial difficulty encountered even with effective patient positioning and longer instruments. Although ultrasound can demonstrate the exact location of the adrenal in these cases, it does not readily allow the safe dissection of the adrenal vein within a field of fat that should not be retracted.

The use of the hand-assisting ports might attenuate some of these issues, but this is unproven. It could also be the case that use of an incision large enough to admit a hand or forearm could abrogate some of the advantage of laparoscopy regarding long-term wound complications and short-term wound pain.

Last, one must keep the 5% conversion rate to open surgery in mind. Thus any advantage to the 19 nonconverted cases must be weighed against the possible disadvantage of urgent conversion to the 20th patient. Furthermore, there is such a breadth of patient response to equivalent injuries that this technique will present no advantage to some. Published series consistently show a subset of patients who tolerate open surgery with little morbidity and another subset of patients who do not tolerate even laparoscopic surgery without substantial morbidity and prolonged hospital stays.23 We are presently unable to reliably predict which patients will not benefit from a less invasive technique.

General Considerations

There are a few general recommendations that reduce the difficulty of laparoscopic adrenalectomy. First, any bleeding substantially impairs visualization. Dissection should be gentle and every act of tissue division accompanied by a hemostatic maneuver. Second, irrigation to remove obscuring blood cannot be reliably evacuated. Irrigation generally should not be used, as it tends to accumulate and obscure the bed of dissection. Third, removal of blood by suction tends to collapse the operative field and lead to tedious adjustment of retraction. For these reasons, small neurosurgical patties or rolled Kitner sponges are the best way to remove blood and to control minor bleeding. The use of instruments with hemostatic capability, such as ultrasonic shears or bipolar vessel sealing devices, should be used. Fourth, manipulation of instruments through the most lateral port is impaired by patients with wide hips. Port sites should be placed at least 7 cm apart to avoid limitations from instrument crowding. Thus the details of the patient's position and the placement of the ports are not routine and should not be delegated. Finally, the adrenal itself cannot be gripped and retracted directly without rupture and bleeding. Retraction should be performed by leaving periadrenal fat strategically attached to the adrenal and gripping the fat or by elevation of the adrenal from beneath. The specimen side of the adrenal vein after ligation can also be used as a handle for retraction. Otherwise, a rolled Kitner sponge held with a grasper can provide gentle and effective traction.

Positioning

As in all operations, patient positioning and exposure are critical to the success of the laparoscopic adrenalectomy. For the lateral transperitoneal approach, the lateral decubitus position favors retraction of the abdominal viscera by gravity and facilitates exposure of the adrenal gland (Fig. 63-1). In obese patients, it may be a useful position for the anterior border of the patient's body near the edge of the bed and may allow the abdominal pannus to hang over the edge. The surgical table should be flexed with the center of the break in the table located approximately at the midpoint between the costal margin and the iliac crest to facilitate the greatest exposure. Exposure can be improved by raising a kidney rest. Care should be taken during flexion in the elderly and in patients with spine disease. The patient should be secured to the table, an axillary roll placed, and all pressure points should be adequately protected.

Instrumentation

Selection of the appropriate instruments can greatly facilitate visualization, exposure, and dissection. A high-definition video camera and monitors in conjunction with a 30-degree laparoscope provides the best visualization of the operative field. Fan retractors provide excellent exposure with the least risk of injury to the liver and spleen. Other essential equipment includes blunt dissectors, an endoscopic clip device, a laparoscopic bag, Kitner sponges, and a hook electrocautery. Laparoscopic devices, such as the Harmonic scalpel (Ethicon, Cincinnati, OH) or LigaSure (Valleylab, Boulder, CO), are useful and likely decrease operation times.

Right Laparoscopic Adrenalectomy

The patient is placed in the left lateral decubitus position, and the surgeon marks four-port sites along the right costal margin from the xiphoid to the midaxillary line (Fig. 63-2). Either a Veress needle entry or a muscle splitting open entry can be used to gain access to the peritoneal cavity. After insufflation of the peritoneal cavity and placement of additional ports under direct vision, the fan retractor is placed in the most medial port and the camera is placed in the second most medial port. Figure 63-3 shows the initial view of the right upper quadrant after entry is achieved. The hepatic flexure of the colon is freed from its attachments and allowed to retract inferomedially from gravity. The fan retractor initially retracts the right lobe of the liver in the medial direction, and the right triangular ligament is taken down with a hook electrocautery. This mobilization enables superior and anterior retraction of the right lobe of the liver, which uncovers the retroperitoneum near the adrenal gland (Fig. 63-4). In most cases, the kidney, periadrenal fat, and IVC are visible after this maneuver.

We begin the dissection in the superolateral border of the periadrenal fat with a hook electrocautery. This exposes the diaphragm posteriorly, and the dissection is carried out in the medial direction along the superior border of the periadrenal fat (Fig. 63-5). A few small arteries are typically located in this area, which can be controlled with electrocautery, clips, or a hemostatic device. Careful dissection with blunt graspers should be used while approaching the IVC, near the superomedial border of the periadrenal fat. After establishing the superomedial corner of the periadrenal fat, the dissection is carried down in the caudal direction between the IVC and periadrenal fat (Fig. 63-6). The adrenal vein typically resides near the top third of this medial border and approaches the IVC at approximately a right angle. After clip or stapler ligation of the adrenal vein, this medial plane of dissection opens significantly (Fig. 63-7). Some surgeons routinely divide the adrenal vein with the LigaSure device without the use of a clips or staples (Fig. 63-8).

At this point, the specimen side of the adrenal vein can be grasped for retraction. The inferomedial border of the dissection also requires careful blunt dissection, with special attention to avoid injuring the renal hilar vessels. The dissection is then carried laterally along the superior surface of the kidney. Special care must be taken to avoid accidental ligation of any arterial branches to the superior pole of the kidney. Once the plane of dissection is established between the inferior border of the periadrenal fat and the kidney, the only remaining attachments are posterior and lateral to the adrenal gland. A blunt grasper can be used to elevate the adrenal gland in the anterior direction, with special care to avoid disruption of the adrenal capsule. The remaining posterior and lateral attachments can be divided with a LigaSure or Harmonic scalpel device. The dissection should clear all fibrofatty and lymphatic tissue from the diaphragmatic surface. Once all attachments are divided, the gland is placed into an endoscopic bag for removal. If appropriate, the mouth of the bag can be exteriorized and the specimen can be morcellated and removed through a port incision. Otherwise, dilation of the fascia and skin are often required to remove the specimen en bloc.

Left Laparoscopic Adrenalectomy

The steps are the same as the right adrenalectomy, with a few differences that will be delineated. The patient is placed in the right lateral decubitus position and the surgeon marks three- or four-port sites along the costal margin from the xiphoid to the posterior axillary line (Fig. 63-9). Sometimes the fourth port is not needed, as the spleen retracts medially with gravity. After access and insufflation of the peritoneal cavity, the splenic flexure of the colon is taken down (Fig. 63-10). The left liver and spleen are mobilized from the diaphragm using hook electrocautery. With medial mobilization of the spleen, the retroperitoneum is exposed. The left kidney, periadrenal fat, and tail of the pancreas are often visualized at this point. The dissection begins in the superolateral corner and proceeds in the medial direction between the spleen and the superior border of the adrenal gland (Fig. 63-11). The splenic vessels are often in close proximity to this plane of dissection. Once the superomedial corner is reached, the tail of the pancreas and the inferior phrenic vein can often be seen. The appearance of the pancreas tail can be similar to the adrenal gland. The dissection continues in the inferior direction along the medial border. The left adrenal vein is often located in the inferomedial portion of the dissection. After adrenal vein ligation, the dissection continues along the inferior border between the adrenal gland and the kidney (Fig. 63-12). In a similar fashion to the right adrenalectomy, the remaining posterior and lateral attachments are divided flush to the surface of the kidney and diaphragm, and the adrenal tumor is removed in bloc with the surrounding periadrenal fat.

Retroperitoneoscopic Adrenalectomy

Retroperitoneoscopic adrenalectomy involves directly accessing the retroperitoneal space from the posterior approach. This does not entail entrance into the peritoneal cavity, and therefore it is not laparoscopic surgery. Unlike laparoscopic adrenalectomy, the retroperitoneoscopic approach does not require mobilization of peritoneal organs (e.g., liver, spleen, colon). Furthermore, the surgeon can access both adrenal glands from the same position, which minimizes operative time during bilateral adrenalectomy. Retroperitoneoscopic adrenalectomy is particularly useful for patients with intraperitoneal adhesions from previous laparotomy and is most suitable for small lesions positioned well above the renal hilum that do not have radiographic evidence of local invasion.

First, the patient is intubated, and all tubes and lines are placed in the supine position. Then the patient is flipped into the prone position, with the hips and knees flexed. This positioning requires the use of bolsters across the chest and hips, as well as sufficient padding for the face, arms, and knees. The abdomen should hang down between the two transversely positioned bolsters.

A small transverse incision is made just caudal to the tip of the 12th rib, and sharp dissection is used to dissect through the subcutaneous tissues and deep fascia. The length of this incision should be around 1.5 cm, which should be enough to accommodate the surgeon's index finger. Digital examination with the index finger can be used to confirm that the dissection is through the deep fascia, and it allows palpation of the smooth underside of the ribs. A second lateral 5-mm port is placed at near the midaxillary line at the same craniocaudal level under direct palpation using the index finger as a guide through the first incision. Then a third 5-mm port is placed similarly under digital palpation, just lateral to the paraspinous muscles at the same craniocaudal level. This medial port should be approximately 3 or 4 cm caudal to the lowest rib.

Then a 12-mm balloon port is placed in the middle incision to ensure that an airtight seal and the space are insufflated to a pressure of 20–30 mm Hg. A 30-degree 10-mm scope is placed in the middle trocar with the angle toward the ceiling. A blunt grasper is used though the lateral port to dissect through Gerota's fascia. Using blunt dissection, the tissues around the medial and lateral ports are cleared and space is created posterior to kidney and adrenal gland. Usually, the paraspinous muscles can be seen medially. With some blunt dissection, the peritoneal lining can be visualized laterally. At the floor of the dissection (anterior), careful blunt dissection can be used to visualize the kidney.

Dissection is carried along the superior border of the kidney, from lateral to medial to separate the top of the kidney from periadrenal fat. Usually during this portion of the dissection, the adrenal gland itself becomes evident through the periadrenal fat. On the right side, the IVC is found anterior and medial to the inferomedial border of the periadrenal fat. The adrenal vein is usually anterior and thus can be difficult to visualize. Division of the adrenal vein can be done with a LigaSure device with or without clips. The specimen side of the adrenal vein can be used to retract the adrenal gland in the cephalad and posterior dissection. The remaining attachments between the periadrenal fat anteriorly and superiorly can be divided with a LigaSure device or electrocautery. As with laparoscopic adrenalectomy, the small adrenal arteries can be controlled with either hook electrocautery or a hemostatic device; clips are usually not required. Small holes in the peritoneum are of no significant consequence and do not require repair. Removal of the specimen can usually be achieved without morcellation or extension of the incision. Closure of the deep fascia in the middle incision usually requires only a single simple nonabsorbable suture. Hernia through these posterior incisions is uncommon.

Endoscopic adrenalectomy is both safe and effective in experienced hands; however, there are many potential complications with this operation. The most common complications include bleeding (5.9%), wound infection (1.5%), cardiac complications (0.8%), solid-organ injury (0.7%), and pulmonary complications (0.6%).24

The specific risks of the procedure are related to the fact that the adrenal glands are deeply situated in the retroperitoneum and in close proximity to large vascular structures and other organs. Consequently, minimally invasive adrenalectomy poses the same anatomic risks as open adrenalectomy: major vascular injury (IVC, splenic vessels, renal vessels) and injury to the spleen, liver, and colon. Although rare, transection of the porta hepatis, hepatic artery, ureter, and renal artery has been reported.25

Pneumoperitoneum poses several risks for this operation aside from traumatic injury relating to port placement. The dissection of the adrenal gland is in close proximity to the posterior aspect of the diaphragm, so ipsilateral pneumothorax is a potential complication. A small pneumothorax can be followed without intervention, and larger defects can be treated with a tube thoracostomy. The pneumoperitoneum can also impair venous return that can be particularly dangerous in the setting of catecholamine surges during resection of pheochromocytoma. This risk can be minimized with pre- and intraoperative hydration. The spleen and liver are also at risk for injury during laparoscopic adrenalectomy; these organs can sustain trocar injuries, capsular tears from grasping or retraction, or vascular injury.

The most life-threatening complication of laparoscopic adrenalectomy is a vascular injury, which results from the limitations of visualization and lack of tactile confirmation. On the right, the renal vein can have an oblique course and course through the inferior portion of the dissection, causing confusion with the adrenal vein. The right adrenal vein is often well visualized with laparoscopic technique but is also of variable location in a superior-inferior plane and anterior-posterior plane. A vein with a diameter significantly smaller than the length of a standard endoscopic clip should be viewed with skepticism if thought to be the adrenal vein. A vein with a diameter significantly larger than an endoclip or that does not clearly connect to the variegated dark yellow adrenal gland is a suspect for the renal vein and should not be divided without certain identification.

On the left, the tail of the pancreas is encountered, and it can often appear similar to the adrenal with its lobular consistency. However, the pancreas is a distinct grayish-white color in contrast to the characteristic bright coloration of the dark yellow adrenal. The granularity of the adrenal is also much finer than the lobules of the pancreas. In addition, there can be a segmental upper pole renal artery that lies just deep to the lower portion of the adrenal. The named arteries of the adrenal are all quite narrow, in the 0.5-mm range, and are often not seen during dissection. Division of an identifiable artery should therefore be very carefully considered. Any major vascular injury should prompt immediate conversion to an open technique. Regarding retroperitoneoscopic adrenalectomy, higher insufflation pressures are tolerated better with less hemodynamic compromise, in comparison to the laparoscopic technique. Intraoperative hypercarbia can be relieved by releasing insufflation and hyperventilating the patient. Subcutaneous emphysema and subcostal nerve dysfunction can be observed after retroperitoneoscopic adrenalectomy, and both are transient in nature.

Open adrenalectomy can be performed via multiple approaches, depending on tumor characteristics, patient body habitus, and surgeon experience with each technique. As mentioned previously, the laparoscopic approach is not appropriate for large tumors or those with local extension; the open approach is the procedure of choice in these cases. The open approach should also be performed in cases where laparoscopy is unsuccessful or when a major vascular or visceral injury occurs. The main open approaches to the adrenal glands are addressed as follows.

Anterior Approach

The anterior approach provides excellent exposure and allows access to both adrenal glands as well as extra-adrenal foci as in the case of pheochromocytoma. The patient is placed in the supine position on the operating table, and either a midline laparotomy or bilateral subcostal incision can be used for this approach with excellent exposure. For right-side access, the hepatic flexure of the colon is taken down inferiorly, the liver is retracted superiorly, and a Kocher maneuver is performed to expose the retroperitoneal space. Gerota's fascia is identified and incised. Once the adrenal gland is exposed, the lateral and superior aspects of the gland are mobilized and the adrenal vein is ligated and divided. Given the proximity of the right adrenal gland to the IVC, the surgeon must use care when dissecting and ligating the right adrenal vein. The left adrenal gland can be exposed from an anterior approach by a medial visceral rotation of the stomach, spleen, splenic flexure of the colon, and pancreas toward the midline. The left adrenal vein can drain either into the left renal vein or the left inferior phrenic vein. The remainder of the dissection is similar to the right side.

Posterior Approach

The posterior approach is particularly useful for patients with adrenal disease who have undergone prior abdominal surgery. These patients might have dense adhesions that make an intra-abdominal exposure formidable. In this operation, the patient is placed in the prone position on the operating table, and a curvilinear incision is made starting in a paramedian line and extending laterally. After the skin and subcutaneous tissues are incised, the latissimus dorsi muscle is divided with electrocautery near its origin and the serratus posterior is divided in a similar way. The 12th rib is removed to facilitate the exposure, and the 11th rib and the pleura are retracted superiorly, which exposes the underlying Gerota fascia. The fascia is incised, and the adrenal gland and the kidney are exposed. The superior vessels are ligated and divided, and the superior aspect of the gland is dissected free. After the gland is mobilized, the adrenal vein is isolated, ligated, and divided. When the gland has been removed, closure is performed in layers.

Thoracoabdominal Approach

The thoracoabdominal incision, though morbid, has great utility for the exposure and removal of large tumors. The patient is placed in the anterolateral position, and the table is rotated to facilitate the exposure. The dissection is carried down between the eighth and ninth ribs, which allows the full exposure of the adrenal gland, renal fossa, and surrounding tissues. The remainder of the dissection is carried out as mentioned previously. If the pleural space is entered, a tube thoracostomy should be placed, and a postoperative chest x-ray obtained to exclude pneumothorax.

Safe and effective resection of adrenal tumors presents both anatomic and physiological challenges for the surgical team. Preoperative planning is critical with particular consideration of the size, radiographic consistency, and specific hormonal products for each tumor. For resection of benign adrenal tumors, minimally invasive adrenalectomy has been shown to be safe, effective, and offers the patient decreased surgical morbidity and decreased length of stay. With improved technologies and further study, the role of minimally invasive surgery for adrenal disease may expand to include malignant disease both for palliative and curative intent. Open adrenalectomy, however, remains an important operation for large and malignant lesions.