心内直视术患者甲状腺激素的变化

Peroperative Changes in Thyroid Hormone in Patients Undergoing Cardiac Surgery with Cardiopulmonary Bypass

探讨体外循环心内直视术患者血液中的甲状腺激素变化规律以及临床意义。选择 19例行体外循环心内直视术患者 ,分别采术前、术中及术后 2、12、2 4、48h血样 ,分析血清中 FT3、FT4、T3、T4、r T3和 TSH浓度。结果 :术中和术后 48h内的 FT3、FT4、T3、T4浓度均明显低于术前 (P<0 .0 5 ) ,T4仍属正常值范围 ;r T3术后 12、2 4、48h均明显高于术前、术中和术后 2 h(P<0 .0 5 ) ;TSH无明显变化 (P>0 .0 5 )。提示在术中和术后 48h内 ,甲状腺激素变化是围绕着机体的自我保护调节使血中的 FT3、FT4、T3浓度处于较低水平波动 ,出现了“低 T3综合症”,并在此浓度基础上相对稳定 ,达到一个新的动态平衡 ,T4和 TSH浓度维持在正常范围内在平衡中起着重要作用。

Purpose:To elucidate the changes and clinical significance of thyroid hormone in patients before,during and after intra cardiac surgery under direct vision with cardiopulmonary bypass (CPB). Methods:Triiodothyronine (T 3),thyroxine (T 4),free triiodothyronine (FT 3),free thyroxine (FT 4),reverse triiodothyronine (rT 3) and thyroidstimulating hormone (TSH) in serum of 19 patients,(6 males,13 females, aged 7~84 years with average 32.34) were determined preoperatively, during operation and 2,12,24,48 h postoperatively. Results:T 3,FT 3,FT 4 and T 4 showed obvious decrease postoperatively ( P <0.05),but T 4 was within normal range.rT 3 increased obviously 12,24 and 48 h postoperatively compared with that preoperatively ,during operation and 2 h postoperatively ( P <0.05).There was no significant change in TSH ( P >0.05).Conclusion:The changes in thyroid hormone is adjusted due to self-protection of the organism during operation to 48 h postoperatively to cause“ low T 3 syndrome”,i.e.low T 3,FT 3 and FT 4 concentrations in the presence of normal T 4 and TSH concentration and reaches a new dynamic balance on the basis of this concentration.The maintenance of normal T 4 and TSH concentrations plays an important role in the new dynamic balance.