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Clinical features of pheochromocytoma and perioperative anesthetic management.

OBJECTIVE
To investigate clinical features of pheochromocytoma and summarize experiences of anesthetic management during the perioperative period.


METHODS
Two hundred and fifty eight patients who were diagnosed with pheochromocytoma in our hospital were reviewed retrospectively for clinical features. According to different preoperative pharmalogical preparations, perioperative mortalities were analyzed in three periods (Period 1: January 1955 - December 1975; Period 2: January 1976 - December 1994; Period 3: January 1995 - July 2001). In Period 3, hemodynamic changes in the patients undergoing different anesthetic methods were analyzed.


RESULTS
About 5.8% (15/258) of pheochromocytoma was an integral part of multiple endocrine neoplasia (MEN) type II or mixed type. Sixty percent (149/249) of the patients who had undergone surgery possessed evidence of catecholamine cardiac toxicity preoperatively. Impaired glucose tolerance was found in 59% (147/249) of the patients before surgery. Perioperative mortality was significantly decreased from 8% (5/60) in Period 1 to 1.2% (1/75) in Period 2 (P < 0.01). No perioperative deaths occurred in Period 3. The volume infused during the operation was significantly higher both in the epidural anesthesia group (3474 ml +/- 624 ml, P < 0.01) and in the epidural plus general anesthesia group (3654 ml +/- 475 ml, P < 0.01) than in the general anesthesia group (2534 ml +/- 512 ml). There were favorable hemodynamic characteristics in patients before removal of the tumor in the epidural anesthesia group and in the epidural plus general anesthesia group, as compared with the general anesthesia group.


CONCLUSIONS
A positive surgical outcome of the excision of pheochromocytoma depends on multiple factors, including careful assessment of potential vital organ damage before surgery and restoration of blood volume by establishing alpha-blockade preoperatively, meticulous anesthetic management of patients during surgery, and appropriate circulatory support after surgery.