Minimally Invasive Adrenalectomy refers to the removal of the adrenal gland through small incisions in the abdomen. Almost all adrenal tumors can be removed through a laparoscopic, hand-assisted, or robotic-assisted technique, with notable exceptions involving the size and nature of the adrenal lesion.
The first laparoscopic adrenalectomy was performed by Gagner and colleagues in 1992.  Desai and colleagues reported the first robotic-assisted adrenalectomies in 2002. They performed two successful transperitoneal adrenalectomies (one right and one left) each in less than 3 hours with satisfactory recovery using the daVinci robotic system. 
As more surgeons have become proficient with minimally invasive surgical techniques, the indications for minimally invasive approachs have expanded. Caution is advised with benign lesions greater than 12 cm, metastatic or primary malignancies, and lesions known to involve surrounding viscera, lymph node basins, or vascular structures. [3,4]
Much controversy has surrounded using minimally invasive approaches in the treatment of metastatic disease. A Scandinavian multicenter study published in 2009 addressed this question through the review of 41 adrenalectomies performed for malignant tumors between January 1997 to November 2008. Pathohistological analysis of the 31 patients with metastatic lesions revealed 12 colorectal, 9 renal cell carcinoma, 5 lung carcinoma, 4 melanoma, and 1 hepatocellular metastases. The resection margins were not free in one case. With a median follow-up of 25 months there were no local recurrences. From these data they concluded that laparoscopic trans-abdominal adrenalectomy for metastases is feasible. 
- Hormonally active adrenal tumors (Aldosteronoma, Pheochromocytoma, Cortison-producing adrenal tumors)
- Nonfunctioning adrenal lesions – incidentalomas, cysts, myelolipoma, hemorrhage
- Nonfunctioning adrenal lesions with progressive growth
- Solitary adrenal metastasis with a negative metastatic survery
- Primary malignancies with a negative metastatic survey
- Benign lesions > 12 cm
- Minimal local invasion of adjacent viscera, lymph nodes, or vascular structures
- Feminizing/Virilizing Adenoma – high proportion are malignant
- Multiple previous abdominal surgeries (may use the retroperitoneal approach)
- Extensive invasion of adjacent viscera, lymph nodes, and/or vascular structures
- Metastatic disease involving more than the adrenal gland
- Metastatic pheochromocytoma to periaortic nodes
- Undiagnosed or uncontrolled coagulopathy of platelet dysfunction
- Other contraindications for general anesthesia and laparoscopy
The most important preoperative procedure is to establish a firm diagnosis. Once it is established that the adrenal mass is benign and non-functional, special pre-operative considerations beyond those necessary for any surgical intervention are not required. A mechanical bowel-preparation is preferred by some surgeons.
Disease specific considerations 
Non-functioning tumors less than 3 cm that are homogeneous and have low density on CT or MRI can be safely followed and do not require removal. Functioning tumors, and those greater than 5 cm should be removed because of the concomitant risk of cancer. Tumors 3-5 cm in size are resected if the CT or MRI shows lesions that are high density, have irregular borders, demonstrate heterogeneity, or have delayed wash out of contrast. Pheochromocytoma, adrenal carcinoma, and metastasis are more likely in these instances.
Functional Non-malignant tumors
Careful preoperative control and monitoring of hormonally active tumors is required. Fluid shifts, electrolyte abnormalities, and blood pressure fluctuations are not uncommon perioperatively. Collaboration with an endocrinologist and anesthesiologist experienced with adrenal disease may be helpful in these situations.
Blood pressure control with calcium channel blocker and diuretics and hypokalemia correction with spironolactone, amilioride, or eplerenone may be required.
Treatment with alpha-adrenergic blockers should be started as soon as the diagnosis is established. Ten to fourteen days of phenoxybenzamine will provide alpha-blockade for most patients. Doses start at 10 mg/12 hours and are titrated 10-20 mg every 2-3 days up to doses that can be as high as 300 mg/day as allowed by the patients amount of postural hypotension. Metyrosine, doxazosin, and/or prazosin may also be added for effectiveness. Once alpha-blockade is established, beta-blockers can also be used to control hypertension. Of note, opiods should be avoided as they may precipitate an adrenal crisis due to histamine release. Intra-operatively, an arterial line is placed to help with blood pressure monitoring. Nitroprusside and beta-blockers should be immediately available to address sudden hypertension or any cardiac arrythmias that may arise. Avoid excessive gland manipulation as this may precipitously increase plasma catecholamine levels.
Drugs for hypercortisolism are mainly used as adjuvant therapy. For patients who require total adrenalectomy, corticosteroid maintenance therapy is required. Note, however, that no cortisol is given until the adrenals are surgically removed.
Primary Adrenocortical Carcinoma
Fifty percent of patients have symptoms related to hypersecretion of hormone and should be treated accordingly. A metastatic work-up may reveal distant metastasis at initial presentation. In this instance, resection does not improve survival.
Patients occasionally develop transient aldosterone deficiency after adrenalectomy. Symptoms include postural hypotension and hyperkalemia. Treat with fludrocortisones.
For patients who require total adrenalectomy (bilateral adrenalectomy) maintenance therapy of cortisol and mineralcorticoids is required. On the first day give 100 mg of hydrocortisone IV q 8 hours. On the second day 50 mg IV q8 hour, taper thereafter as tolerated. Once hydrocortisone is reduced below 50 mg/d, add fludrocortisone 0.1 mg orally daily. Patients who have had bilateral adrenalectomy and are on maintenace therapy can develop addisonian crisis when under stress and should be counseled as to the symptoms of fever, abdominal pain, and hypotension. Lab abnormalities also include hyperkalemia. Treat with saline and cortisol bolus. 
Laparoscopic adrenalectomy has a significantly lower complication rate compared to open adrenalectomy (10.9% vs. 25.2%). Mortality 0.3% vs. 0.9% 
- Pneumothorax – 1-2%
- Vascular injury – 0.7 – 5.4%
- Tranfusion rates up to 10%
- Vena cava or right adrenal vein on the right
- Dissection of left renal hilum on left
- Bowel injury – 0-1.3%
- Pancreatic injury on the left – 0.5 – 8.6%
- Superficial laceration of the liver or spleen – 0.5-2.5%
- Bleeding – 4.7%
- Wound complications – 1.4%
- Thromboembolic events – 0.5%
- Cardiac events – 0.3%
- Urinary related events – 0.5%
- Pulmonary infections – 0.2%
- Wound infections – 0.3%
- Gagner M, Lacroix A, Bolte E. Laparoscopic adrenalectomy in Cushing’s syndrome and pheochromocytoma. NEJM. 327:1033, 1992.
- Desai MM, Gill IS, Kaouk JH, et al. Robotic-assisted laparoscopic adrenalectomy. Urology. 60:1104-1107, 2002.
- Assalia A, Gagner M. Laparoscopic Adrenalectomy. In The SAGES Manual: Fundamentals of Laparoscopy, Thoracoscopy, and GI Endoscopy, 2nd Ed. Carol E.H. Scott-Connor (ed.), Springer Science+Business Media: New York, 2006. pp. 452 – 466.
- Gagner M, Pomp A, Heniford BT, et al. Laparoscopic Adrenalectomy: lessons learned from 100 consecutive cases. Ann Surg. 226:238-247, 1997.
- Marangos IP, Kazaryan AM, Rosseland AR, et al. Should we use laparoscopic adrenalectomy for metastases? Scandanavian multicenter study. J Surg Onc. 100:43-47, 2009.
- Gawande AA, Moore FD. Laparoscopic Adrenalectomy. In Maingot’s Abdominal Operations, 11th ed. MJ Zinner, SW Ashley (eds.), McGraw-Hill: New York, 2007. pp. 1205-1216.
- Duh Q, Liu C, Tyrrell JB. Chapter 33. Adrenals. In Current Diagnosis & Treatment: Surgery, 13th ed. GM Doherty (ed.), McGraw-Hill: New York, 2010. http://www.accesssurgery.com/content.aspx?aID=5310456
- Brunt LM, Doherty HF, Norton JA, et al. Laparoscopic adrenalectomy compared to open adrenalectomy for benign adrenal neoplasms. J Am Coll Surg. 183:1-20, 1996.