[Study on thyroid defunctionalization method for the preoperative preparation of hyperthyroid operation].

Objective: To set up and publicize the thyroid defunctionalization method for the preoperative preparation of hyperthyroid operation.

Methods: 476 hyperthyroid patients admitted in our hospital from March 1990 to February 2005 were studied by groups. They were divided randomly into a test group (244 patients), in which "preoperative preparation method of sequential thyroid defunctionalization" was applied to hyperthyroid patients, and based on the different drug dosages and treating terms used, further 4 subgroups (A, B, C and D) were divided to observe the treatment efficiency; And a control group (232 patients), in which antithyroid drugs and iodine preparation were applied preoperatively to cases. Thyroid functions in every stage of treatment were tested by radioimmunoassays (RIA), and operative bleeding volumes and postoperative complications were observed.

Results: Compared to the control group, the thyroid congestion and surface varices were alleviated in the test groups, in which the thyroid tissue of subgroup A most closed to euthyroidism histologically. The mean operative bleeding volume of test group was less than that of the control group. The bleeding volumes were (324.76 +/- 163.26) mL for the control group, (195.74 +/- 57.07) mL for the subgroup A, (230.00 +/- 70.81) mL for the subgroup B, (240.47 +/- 80.29) mL for the subgroup C and (314.75 +/- 96.46) mL for the subgroup D. There was no significant difference between the control group and subgroup D, but compared with the subgroup A, B, and C, there was the significant difference between control and treated subgroup (P < 0.05). The postoperative complication rate of the test group was 8.61% (21/244), while that of the control group was 17.24 (40/232). There was statistic difference between two groups (P < 0.005).

Conclusion: The key to "preoperative preparation method of sequential thyroid defunctionalization" is as follows: the synthesis of thyroxin should be fully inhibited to thyroid defunctionalized; sufficient exogenous thyroxin should be supplemented; the term of thyroid function compensation should be long enough. The "preoperative preparation method of sequential thyroid defunctionalization" can decrease perioperational complications effectively and operation risks.