Laparoscopic adrenalectomy

Approach to the surgical management of primary aldosteronism

Primary aldosteronism (PA) is the most common cause of endocrine hypertension; it has been reported in more than 11% of referred hypertensive patients. PA may be caused by unilateral adrenal involvement [aldosterone producing adenoma (APA) or unilateral adrenal hyperplasia (UAH)], and bilateral disease (idiopathic adrenal hyperplasia). Only patients with unilateral adrenal hypersecretion may be cured by unilateral adrenalectomy, while patients with bilateral and non-surgically correctable PA are usually treated by mineralocorticoid receptor antagonists; thus the distinction between unilateral and bilateral aldosterone hypersecretion is crucial. Most experts agree that the referral diagnostic test for lateralization of aldosterone hypersecretion should be adrenal venous sampling (AVS) because the interpretation of other imaging techniques [computed tomography (CT), magnetic resonance imaging (MRI) and scintigraphy] may lead to inappropriate treatment. Adrenalectomy represents the elective treatment in unilateral PA variants. Laparoscopic surgery, using transperitoneal or retroperitoneal approaches, is the preferred strategy. Otherwise, the indications to laparoscopic unilateral total or partial adrenalectomy in patients with unilateral PA remain controversial. Adrenalectomy is highly successful in curing the PA, with correction of hypokalemia in virtually all patients, cure of hypertension in about 30-60% of cases, and a marked improvement of blood pressure values in the remaining patients. Interestingly, in several papers the outcomes of surgery focus only on blood pressure changes and the normalization of serum potassium levels is often used as a surrogate of PA recovery. However, the goal of surgery is the normalization of aldosterone, because chronically elevated levels of this hormone can lead to cardiovascular complications, independently from blood pressure levels. Thus, we strongly advocate the need of considering the postoperative normalization of aldosterone-renin ratio (ARR) as the main endpoint for determining outcomes of PA.

Review of surgical management of aldosterone secreting tumours of the adrenal cortex

AIMS

To evaluate the investigation and surgical management of primary hyperaldosteronism. Retrospective case note analysis of thirty-three patients who underwent adrenalectomy for primary hyperaldosteronism between 1982 and 2001 and a current relevant literature review.

METHODS

The records of twelve male and twenty-one female patients, age range 18 to 81 (mean 48 years) were reviewed. Eleven operations were performed by an open approach and twenty-two laparoscopically. Preoperative investigations included computed tomography (CT), magnetic resonance imaging (MRI), selective venous sampling and seleno-cholesterol isotope scanning, along with biochemical and hormonal assays. Twenty-six benign adenomas, three nodular hyperplastic lesions, one primary adrenal hyperplasia and three functional carcinomas were excised. Mean follow up was 12 months.

RESULTS

Patients had a mean blood pressure of 185/107 mmHg for 6.2 years mean duration. The mean severity of hypokalaemia was 2.7 mmol/l. Sensitivity of CT scanning was 85%, and of MRI 86%. Fifty percent of seleno-cholesterol scans were accurate. Mean operating time was 158 min for laparoscopic adrenalectomy whilst open surgery took 129 min (p=0.2, NS). Two cases commenced laparoscopically required open access for control of primary haemorrhage whilst one other bleed was managed via the operating ports. Mean postoperative stay was significantly shorter for the laparoscopic group (3 days compared with 7.9 days, p<0.0001). Thirty day mortality was zero. There were three infective complications in the open group (two chest, one wound) with no postoperative complications in the laparoscopic group. All patients were cured of hypokalaemia, whilst 62% cure of hypertension was achieved. Of those patients whose blood pressure was improved preoperatively by spironolactone 78% were cured by adrenalectomy. Adrenalectomy led to an overall reduction in the mean number of anti-hypertensive medications (2.3 drugs preoperative to 0.6 postoperative, p<0.0001). Of those not cured, 58% had improved blood pressure control requiring less medication on average (1.6 drugs compared with 2.6 drugs, p=0.08). Mean age of patients not cured by surgery was 55 years, whilst those cured was 44 years (p=0.03).

CONCLUSIONS

Primary hyperaldosteronism is a rare but important cause of hypertension. Selective venous sampling is a useful tool where investigations are inconclusive and fail to lateralise secretion. Patients with primary hyperaldosteronism enjoy lower complication rates and earlier discharge with the advent of laparoscopic surgery. Most patients will be cured of their hypertension and all of hypokalaemia. Laparoscopic adrenalectomy is now the accepted method of surgery for benign hyperaldosteronism. Those with bilateral disease due to idiopathic hyperaldosteronism (IHA) are not candidates for surgery and should be treated medically.

Laparoscopic and open surgery for pheochromocytoma

BACKGROUND

Laparoscopic adrenalectomy is a promising alternative to open surgery although concerns exist in regard to laparoscopic treatment of pheocromocytoma. This report compares the outcome of laparoscopic and conventional (open) resection for pheocromocytoma particular in regard to intraoperative hemodynamic stability and postoperative patient comfort.

METHODS

Seven patients laparoscopically treated (1997-2000) and nine patients treated by open resection (1990-1996) at the National Hospital (Rikshospitalet), Oslo. Peroperative hemodynamic stability including need of vasoactive drugs was studied. Postoperative analgesic medication, complications and hospital stay were recorded.

RESULTS

No laparoscopic resections were converted to open procedure. Patients laparoscopically treated had fewer hypertensive episodes (median 1 vs. 2) and less need of vasoactive drugs peroperatively than patients conventionally operated. There was no difference in operative time between the two groups (median 110 min vs. 125 min for adrenal pheochromocytoma and 235 vs. 210 min for paraganglioma). Postoperative need of analgesic medication (1 vs. 9 patients) and hospital stay (median 3 vs. 6 days) were significantly reduced in patients laparoscopically operated compared to patients treated by the open technique.

CONCLUSION

Surgery for pheochromocytoma can be performed laparoscopically with a safety comparable to open resection. However, improved hemodynamic stability peroperatively and less need of postoperative analgesics favour the laparoscopic approach. In experienced hands the laparoscopic technique is concluded to be the method of choice also for pheocromocytoma.

The effects of retroperitoneal carbon dioxide insufflation on hemodynamics and arterial carbon dioxide

BACKGROUND

Laparoscopic techniques are being increasingly used for retroperitoneal surgery. However, hemodynamic and ventilatory efforts of retroperitoneal carbon dioxide (CO2) insufflation have not been studied. We hypothesized that differences in absorptive surface, anatomy, and compartment compliance could result in different hemodynamic and ventilatory effects between retroperitoneal and intraperitoneal insufflation.

METHODS

Pigs (n = 7) were anesthetized and stabilized. The peritoneal cavity was incrementally insufflated with CO2 to a maximum pressure of 25 cm H2O and the gas released. Hemodynamics and arterial blood gas values were recorded initially, at each level of insufflation, and following the pneumoperitoneum release until baseline values were reached. This insufflation protocol was repeated in the retroperitoneum.

RESULTS

Mean arterial pressure (111 mm Hg, 95% confidence interval 99 to 156) and cardiac output (3.7 L/min, 2.8 to 5.2) did not change with increasing insufflation pressure of either intraperitoneum or retroperitoneum. PaCO2 was directly related to insufflation pressure in both spaces, increasing from 41.2 mm Hg (37.3 to 43.4) at baseline to 57.7 mm Hg (47.6 to 82.1) at insufflation pressure of 25 cm H2O. After release of the insufflation gas, time to return to baseline PaCO2 was slightly less from the retroperitoneal space (73 minutes, 45 to 105) than the intraperitoneal (107 minutes, 35 to 175).

CONCLUSIONS

The effects of CO2 insufflation on hemodynamics and PaCO2 are the same in the retroperitoneal and intraperitoneal spaces.

Posterior or laparoscopic approach for adrenalectomy

BACKGROUND

The pathologies and size of adrenal lesions removed through the open posterior and laparoscopic routes share remarkable similarities. This study aims at comparing the relative merits of these two approaches.

METHODS

Patients with adrenal tumors operated on by posterior approach (n = 56) and transabdominal laparoscopic approach (n = 12) between January 1981 and May 1997 were retrospectively reviewed.

RESULTS

The two groups were comparable in terms of age, and the position, size, and weight of the tumor. The operative time of posterior adrenalectomy was significantly shorter than that of laparoscopic adrenalectomy (median 120 minutes versus 160 minutes), whereas laparoscopic adrenalectomy was associated with less parenteral analgesic requirement (median 0 mg versus 225 mg), a shorter hospital stay (median 3 days versus 5 days), and a shorter duration off work (median 11 days versus 26 days). The estimated blood loss was also significantly reduced in the laparoscopic group (median 50 mL versus 150 mL).

CONCLUSIONS

Laparoscopic adrenalectomy is replacing posterior adrenalectomy to become the procedure of choice for the majority of patients undergoing adrenalectomy.