Thyroid function tests in patients undergoing maintenance dialysis: characterization of the 'low-T4 syndrome' in subjects on regular hemodialysis and continuous ambulatory peritoneal dialysis

Thyroid function tests were evaluated in 38 patients on regular hemodialysis (HD), in 36 on continuous ambulatory peritoneal dialysis (CAPD) and in 39 healthy controls. A significant reduction in total thyroxine (TT4), total triiodothyronine (TT3), reverse (rT3), and free T4 (fT4) mean levels and normal TSH, free T3, TBG and albumin concentrations was found in both HD and CAPD patients. A 'low-T4 syndrome' (serum T4 less than 5 micrograms/dl) was found in 9 CAPD (25%) and 20 HD (53%) patients, but none of them had fT4 levels below the normal laboratory range. The only striking difference between low-T4 HD and low-T4 CAPD patients was the significantly lower TBG and albumin serum levels in CAPD group. Low-T4 HD displayed normal TBG levels but enhanced fT4/TT4 and fT4/TT4 X TBG ratios. We concluded that: the abnormalities in thyroid function tests in patients on long-term dialysis (HD and CAPD) do not express the existence of a true hypothyroidism; a different pathogenesis of the low-T4 syndrome in the CAPD and HD groups may be hypothesized: in the former it could be attributed to a reduction in serum-binding capacity for thyroid hormones, in the latter the relative increase in fT4 percentage despite normal TBG levels suggests either the presence of T4-TBG-binding inhibitor(s), or structural abnormalities of thyroid-hormone-binding proteins.     

Troponin T — a reliable marker of perioperative myocardial infarction?

Following cardiac surgery, electrocardiography and creatine kinase isoenzyme MB (CK-MB) activities are of limited value in diagnosing a non-transmural infarction. With the recent availability of an assay to detect serial levels of the specific cardiocyte contractile protein troponin T the possibility has been increased of closing a diagnostic gap among cardiosurgical patients. Ninety patients with severe diffuse three-vessel disease undergoing myocardial revascularization were grouped by their postoperative electrocardiographic (ECG) findings (group I — unchanged ECG; group II — new Q-waves representing perioperative myocardial infarction (PMI)). Serial levels of troponin T and the activity of CK-MB were measured 6, 12, 24 and 48 h after aortic unclamping. The course of CK-MB activity was compared to a profile and values derived from patients with unchanged (n = 1312) or new Q-wave ECGS (n = 89). In 72 patients (80.0%) with unchanged postoperative ECG (group I) serial troponin T levels remained constantly low and reached a median peak value of 0.37 μg/l (quartile 0.13–0.50 μg/l) after 24 h. Serial CK-MB activities demonstrated the typical non-ischemic course with a monoexponential decline from an initial median peak value of 15.5 U/l (quartile 12.0–21.0 U/l) to 7.0 U/l (quartile 6.0–9.0 U/l). In seven patients (7.8%) with new Q-waves and a pathologic CK-MB profile (group II) troponin T reached median levels of 10.47 μg/l (quartile 6.34–12.50 μg/l) (P < 0.001 I vs II). Four of five patients with a new right bundle branch block demonstrated low troponin T levels below 1 μg/l and a normal CK-MB profile. Among six patients with unchanged QRS-configuration and elevated troponin T levels between 0.84 and 4.99 μg/l CK-MB activity showed a characteristic PMI pattern in two patients. Troponin T is characterized by a very narrow margin of normal values represented by a maximum third quartile of 0.50 μg/l. A singular value of troponin after 6 h or 24 h may be sufficient evidence to confirm the diagnosis of a PMI.     

Retransfusion of pericardial blood does not trigger systemic coagulation during cardiopulmonary bypass

Objective: During cardiopulmonary bypass (CPB), systemic coagulation is believed to become activated by blood contact with the extracorporeal circuit and by retransfusion of pericardial blood. To which extent retransfusion activates systemic coagulation, however, is unknown. We investigated to which extent retransfusion of pericardial blood triggers systemic coagulation during CPB. Methods: Thirteen patients undergoing elective coronary artery bypass grafting surgery were included. Pericardial blood was retransfused into nine patients and retained in four patients. Systemic samples were collected before, during and after CPB, and pericardial samples before retransfusion. Levels of prothrombin fragment F₁₊₂ (ELISA), microparticles (flow cytometry) and non-cell bound (soluble) tissue factor (sTF; ELISA) were determined. Results: Compared to systemic blood, pericardial blood contained elevated levels of F₁₊₂, microparticles and sTF. During CPB, systemic levels of F₁₊₂ increased from 0.28 (0.25–0.37; median, interquartile range) to 1.10 (0.49–1.55) nmol/l (p = 0.001). This observed increase was similar to the estimated (calculated) increase (p = 0.424), and differed significantly between retransfused and non-retransfused patients (1.12 nmol/l vs 0.02 nmol/l, p = 0.001). Also, the observed systemic increases of platelet- and erythrocyte-derived microparticles and sTF were in line with predicted increases (p = 0.868, p = 0.778 and p = 0.205, respectively). Before neutralization of heparin, microparticles and other coagulant phospholipids decreased from 464 μg/ml (287–701) to 163 μg/ml (121–389) in retransfused patients (p = 0.001), indicating rapid clearance after retransfusion. Conclusion: Retransfusion of pericardial blood does not activate systemic coagulation under heparinization. The observed increases in systemic levels of F₁₊₂, microparticles and sTF during CPB are explained by dilution of retransfused pericardial blood.     

Paclitaxel treatment reduces neointimal hyperplasia in cultured human saphenous veins

Background: Paclitaxel exerts antiproliferative properties by stabilizing microtubuli of the cell. The substance is in clinical use for drug-eluting coronary stents. We aimed to test the hypothesis that paclitaxel treatment can reduce neointimal hyperplasia in cultured human saphenous veins and thus might be useful for local pharmacologic treatment of vein grafts prior to coronary artery bypass grafting (CABG). Methods: The remnants of saphenous veins from 13 patients undergoing CABG were collected. The development of neointimal hyperplasia was induced using an established organ culture model (incubation time 2 weeks). In the treatment group, paclitaxel was added to the culture medium at different concentrations. Results: Veins treated with 1 μmol/l paclitaxel showed a median increase of intimal thickness of 2 μm (range −76 to 46) above baseline levels, whereas untreated control veins increased by 15 μm (range −3 to 142) (p = 0.022). Treatment with 10 μmol/l paclitaxel resulted in a lower intimal thickness growth of 1 μm (range −82 to 212) above baseline levels (p = 0.035 vs controls). Treatment with 25 or 50 μmol/l paclitaxel did not further inhibit intimal hyperplasia. The neointimal amount of the contractile protein smooth muscle actin (SMA) in paclitaxel 1 μmol/l treated veins was significantly higher than baseline values (p = 0.037). The cytoskeletal protein desmin was predominant in the media, whereas it was less frequently found in the intima, and we observed no difference between controls and paclitaxel treated veins. The proliferation marker ki-67 was occasionally present in the circumferential media, whereas it was almost absent in both the (inner) longitudinal media and the intima. Elastic fibers were present in the media and intima before and after organ culture without significant differences between the groups. Collagen fibers (Masson's trichrome) were found abundantly (80%) in the inner longitudinal media, less commonly (20%) in the outer circumferential media, and they were absent in the intima without difference between the groups. Conclusion: Local paclitaxel treatment reduces neointimal hyperplasia in cultured human saphenous veins, without changing the amount of elastic or collagen fibers. Paclitaxel treatment leads to an increased amount of the contractile protein SMA and thus might have a therapeutic potential for the prevention of vein graft disease.     

Effect of fentanyl-oxygen anesthesia during cardiac surgery on serum thyroid hormones

Twenty-five euthyroid patients who underwent cardiac surgery with fentanyl-oxygen anesthesia were studied. The authors confirm that some thyroid hormones undoubtedly take part in a non-specific pool of reactions caused by surgical stress. For one or more days, all the patients had total triiodothyronine (TT3) and free triiodothyronine (FT3) levels clearly below the normal values, with a parallel increase in reverse triiodothyronine (rT3, biologically inactive). Changes in total (TT4) and free thyroxine (FT4), although significant, were smaller and hard to interpret. The most important changes occurred on the first postoperative day. Of seven patients who before the operation had a TT3 value below the lower normal limit, six had at discharge a mean TT3 level significantly above it. Serum TT3 concentrations could be a reliable prognostic index. High-dose fentanyl anesthesia probably does not affect thyroid hormone response to surgical stress. To date, the mechanisms which cause reduction of serum triiodothyronine have not been fully discovered and it is not known for certain whether this reduction is beneficial to the human organism.     

Vacuum‐assisted closure therapy combined with bi‐pectoral muscle flap for the treatment of deep sternal wound infections

Deep sternal wound infection (DSWI) is a fatal complication after median sternotomy. This study was to assess the effect of vacuum‐assisted closure (VAC) combined with bi‐pectoral muscle advancement flap therapy on rehabilitation for the treatment of DSWI. Fifty‐two patients with DSWI underwent treatment of VAC and bi‐pectoral muscle flap. These patients were followed‐up 12 months postoperation. The patient characteristics, duration of VAC therapy, the mean hospital stay, and postoperative complications were retrospectively analysed. All patients underwent 1 to 3 VAC treatment sessions before closure. Fifty‐one of 52 DSWI patients were cured to discharge; the mean hospital stay was 26.5 days. The drainage tube continued to drain a large amount of bloody fluid in three patients after the wound was closed. Respiratory failure occurred in one patient with severe mediastinal and pulmonary infections and died eventually in hospital. One patient died of acute cerebral haemorrhage during the12‐month follow‐up. VAC therapy combined with bi‐pectoral muscle flap is a simple and effective treatment for DSWIs with short hospital stays and few complications. However, this is a retrospective case series presentation with no comparison group; further large‐scale controlled studies are needed.     

Euthyroid sick syndrome in trauma patients with severe inflammatory response syndrome

Objective： To investigate the alternations of thyroid hormone in traumatic patients with severe inflammatory response syndrome （SIRS）. Methods： Fifty traumatic patients with severe SIRS were enrolled and divided into two groups according to whether they presented multiorgan dysfunction syndrome （MODS）. Thyroid hormone measurements were taken, including total triiodothyronine （ TT3 ）, total thyroxine （TT4）, free triiodothyronine （FT3）, free thyroxine （ FT4 ） and thyroid stimulating hormone （TSH）. The acute physiology and chronic health evaluation II （ APACHE II ） score was calculated according to clinical data. The outcomes of recovery or deterioration were recorded, as well as the length of time from the onset of SIRS to the time thyroid hormones were measured. Results： Euthyroid sick syndrome （ESS） was presented in 45 cases. TT3 level was negatively correlated with APACHE II score （r = -0.330, P 〈0. 05）, and TT3/TI＇4 value was negatively correlated with the duration of SIRS（ r = -0.316, P〈0.05）. TT3, TT4 and levels in MODS patients were significantly lower than those without MODS （ P 〈 0.05 ）. MODS patients got low TT4 or FT4 level more frequently than those without MODS （ P 〈 0.05 ）. Compared with the patients in normal TSH group, the patients with decreased TSH had lower T3, T4, recovery rate and higher APACHE II scores, MODS incidence, but there was no difference between two groups （P〉0.05）. Conclusions： Trauma patients with severe SIRS have high possibility to get ESS, which occurs more frequently and severely in MODS patients. It shows the influences of SIRS on the thyroid axes. With the persistence and aggravation of SIRS, there is a progressive reduction of thyroid hormone.     

Pulmonary lactate release following cardiopulmonary bypass

Objective: The etiology of lung injury following cardiopulmonary bypass (CPB) is multifactorial. Our study focused on quantifying the lactate release from the lungs precipitated by extracorporeal circulation at different time points after the insult. This was complemented by an evaluation of the gas exchange at the level of the alveolar–capillary membrane. Methods: Forty consecutive patients (age 61 ± 11 years, EuroScore 4.7 ± 2.7) undergoing CABG were prospectively analyzed. The data are presented as medians and the interquartile range. Results: The pulmonary lactate release (PLR) increased from a baseline value of 0.033 (range −0.077 to 0.170) to 0.465 mmol/min/m² (range 0.113–0.922), which was seen 6 h postoperatively (P < 0.001). The A-a O₂ gradient increased from 12.7 (range 8.8–15) to 39.1 kPa (range 30.3–46.5) upon discontinuation of CPB (P < 0.001). The systemic arterial lactate (L_S) concentration increased from 1.22 (range 1–1.44) to 3.03 mmol/l (range 2.29–4.76) 6 h after surgery (P < 0.001). The veno-arterial pCO₂ difference (V-A dpCO₂) rose from 0.6 (range 0.5–0.9) to 0.9 kPa (range 0.7–1) (P = 0.014). The mortality in the studied group was 5% (2/40). Conclusions: The lungs were found to be a significant source of lactate, and this pulmonary lactate flux was accentuated by CPB. The PLR correlated with systemic hyperlactatemia as well as the A-a O₂ gradient, and was found to be higher in patients requiring prolonged mechanical ventilatory support. The duration of CPB had a significant impact on the systemic lactate concentrations, V-A dpCO₂ and the A-a O₂ gradient, but not on the PLR.     

Systematic mediastinal lymphadenectomy does not increase postoperative immune response after major lung resections

Objective: To assess the influence of mediastinal lymphadenectomy on postoperative concentration of interleukin 6 (IL-6) and interleukin 1 receptor antagonist (IL-1ra) in serum, sputum, and pleural fluid, in patients operated upon due to lung cancer and benign pulmonary diseases. Methods: Thirty-three patients undergoing uncomplicated resections, including 23 with lung cancer and 10 with benign diseases, were analyzed. In patients with right lung cancer we performed a systematic lymphadenectomy, while in patients with left lung cancer systematic sampling was performed. Serum IL-6 and IL-1ra concentration was measured before and after surgery, and on postoperative days 1, 3, and 7, as well as in sputum at the end of surgery and in pleural fluid on postoperative day 1, by ELISA test. Results: In 23 patients with cancer, 19.0 ± 11.43 mediastinal lymph nodes were removed (in 11 patients with right lung cancer 27.6 ± 7.6 and in 12 patients with left lung cancer 11.1 ± 8.1). No differences were found in serum and sputum concentration of IL-6 and IL-1ra between patients after right and left thoracotomy due to cancer and between patients with cancer and patients with benign diseases. Patients with cancer had a lower concentration of IL-1ra in pleural fluid (median 16950, range 16050–45470.05 pg/ml) than patients with benign diseases (76665.6 pg/ml (range 53618–89617.9); p = 0.0008). In 23 cancer patients a negative correlation between concentration of cytokines in pleural fluid and a number of mediastinal lymph nodes resected was observed (Spearman correlation coefficient for IL-6: r = −0.44, p = 0.04; for IL-1ra: r = −0.57, p = 0.01). Such correlation was not observed for a number of positive N2 lymph nodes. Conclusions: Systematic lymphadenectomy added to major lung resection does not increase postoperative humoral immune response in uncomplicated cases, as measured by levels of IL-6 and IL-1ra in serum, pleural fluid, and sputum.     

Thyroid function in brain-dead donors

Twenty brain-dead potential organ donors were studied prospectively to establish thyroid function. Two or three consecutive blood samples were obtained during brain death. Seven times a sample was available before brain death occurred. Free triiodothyronine (FT3) fell in most patients (80%). Very low (<1.6 pmol/l) and subnormal levels (between 2 and 3 pmol/l) were found in 65% and 15% of the patients, respectively. Serum reverse total triiodothyronine (rT3) was inversely correlated with FT3. Free thyroxine (FT4) was less often decreased (mean 14.68±1.42 pmol/l) and 35% of the patients had normal levels. Mean thyroid stimulating hormone (TSH) remained normal (0.71±0.15 U/ml). The study of consecutive samples during brain death did not show a constant, progressive decrease in hormonal levels. There is no statistical difference between values observed before and after brain death. No correlation was found between FT3 levels and hemodynamic data or immediate allograft function. The pattern of thyroid function in these patients was typical of the sick euthyroid syndrome with a low T3 or low T3 and low T4 serum levels. This syndrome usually does not need to be treated. However, many experiment findings and some clinical data argue in favor of T3 therapy in donors and possibly in recipients. The dosage regimen must be adjusted to be effective without causing harm to multiorgan donors before it can be widely used. It remains to be proved that low FT3 serum indicates low intracellular FT3 and worse metabolic function in clinical conditions.     

Forearm fractures in children. Single bone fixation with elastic stable intramedullary nailing in 20 cases

We present our experience with elastic stable intramedullary nailing (ESIN) used in the single bone fixation of both bones forearm fractures in children. From May 2002 to July 2004, 20 children (14 boys and 6 girls), median age of 10 years (range 6–15 years) were treated with ESIN for 16 closed and 4 grade I open forearm fractures. All patients were reviewed clinically at a median follow-up of 20 months (range 6–30 months). All fractures were radiologically united at a median of 6.7 weeks (6–9 weeks). The median operating time was 35 min (range 25–60 min). The median hospital stay was 2 days (range 1–3 days). Removal of the nails was undertaken in all 20 children at a median of 19 weeks (range 16–24 weeks) post-operatively. At follow-up, a full range of elbow and wrist movements were found in all cases. There was no clinically significant rotational deformity in any case. ESIN seems to be a safe method in the treatment of single bone fixation of both bones forearm fractures in children between 6 and 15 years of age.     

Thoracoscopic resection of bulky intrathoracic benign lesions

Background: Video-assisted thoracic surgery (VATS) is used for the diagnosis and treatment of some mediastinal lesions. However, large-size tumours are usually approached by thoracotomy or sternotomy. We report our experience of a full thoracoscopic approach for bulky intrathoracic lesions. Methods: From November 2002 to March 2007, 14 patients with a bulky intrathoracic mass were referred for resection. The study group consisted of eight females and six males with a mean age of 44 years (range: 13–74). We defined as bulky a mass with a minimal cross-sectional diameter equal to or larger than 50 mm, as measured on the specimen by the pathologist. Results: Thoracoscopic resection was completed in all patients. In 4 cases, the mass originated from the pleura, and in 10 cases from the mediastinum. The larger diameter of the lesion ranged from 50 mm to 160 mm, with a median of 90.2 mm. Operative time, calculated from insertion of the first trocar to skin closure, ranged from 40 to 190 min (mean: 102). Mean chest drain duration was 2.1 days (range: 1–4 days) and the mean hospital stay was 4.3 days (range: 3–11 days). There were no major postoperative complications. The final pathological diagnoses were the following: solitary fibrous tumours of the pleura (4), benign thymic cysts (2), teratomas (2), bronchogenic cyst (1), benign thymoma (1), pleuropericardial cyst (1) and benign neurogenic tumours (3). Conclusions: With experience and use of appropriate instrumentation, resection of bulky intrathoracic lesions by thoracoscopy is feasible and safe. It should be considered as a reliable alternate for tumours that are benign and most often asymptomatic.     

Effects of aprotinin on endothelium-dependent relaxation of large coronary arteries

Objective: Aprotinin is widely used in heart surgery for reduction of intraoperative blood loss. But recent reports presenting results from rat aorta experiments claimed that aprotinin selectively impairs endothelium-dependent relaxation (EDR) as well as basal NO availability in concentrations similar to doses routinely used in cardiovascular surgery. An impairment of coronary EDR by aprotinin would be a great danger for any cardiothoracic intervention. We therefore tested the influence of aprotinin in the coronary arteries of a non-rodent species. Methods: Fresh coronary arteries of pigs were obtained from the local slaughterhouse and transported to our laboratory in cold oxygenated Krebs–Henseleit solution. Five-millimeter long rings were consecutively tested with or without aprotinin in concentrations of 500 KIU/ml (n = 7) or 1000 KIU/ml (n = 6) in oxygenated normothermic Krebs–Henseleit solution. PGF₂ (10 μmol/l) was used for inducing contraction and substance P (10 nmol/l) for inducing EDR, which was calculated in percentage of the precontraction. Indomethacin (10 μmol/l) was added in all measurements to eliminate the influence of prostaglandins. In additional similar experiments (n = 5), the influence of 1000 KIU/ml aprotinin on the EDR caused by the endothelium-derived hyperpolarizing factor (EDHF) was tested using l-NNA (300 μmol/l) to block all NO formation. Results: The EDR of pig coronaries (82 ± 5% or 80 ± 5% of the precontraction in the control tests before and after aprotinin exposure) was not significantly changed by 500 KIU/ml aprotinin (78 ± 7%). A small, but significant reduction of less than 1/10 of the EDR was induced by 1000 KIU/ml aprotinin (74 ± 5%). After accounting for l-NNA for NO blockage, no aprotinin-related difference remained (59 ± 6% vs 60 ± 6% in controls). Conclusion: For clinically relevant concentrations of aprotinin up to 500 KIU/ml, no significant reduction of the EDR can be found in epicardial coronary arteries of the pig. For higher doses of 1000 KIU/ml, a reduction in NO production seems to be the cause of the small but significant reduction of the EDR by aprotinin. Therefore, danger for impairment of coronary EDR by aprotinin at clinical dosage levels, as suggested by studies on rat aortas, seems to be absent in coronary arteries of a large mammalian model.     

Mediastinal goiter; report of a case

A 76-year-old female was admitted to our hospital because of an abnormal shadow on chest computed tomography (CT) which showed the tumor extending from left lower end of the thyroid to the aortic window along the left side of the trachea, indicating the retrosternal goiter. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) were within normal ranges. The tumor was resected through cervical collar incision and median sternotomy. The pathological diagnosis was an adenomatous goiter. The patient was discharged without complications.     

The "low TBG syndrome" in patients on chronic hemodialysis: evolution after renal transplantation

Patients on chronic hemodialysis may have a spuriously low TBG level, tentatively ascribed to uremia-induced changes in TBG immunoreactivity. In order to test this hypothesis, the effect of restoration of a normal renal function on TBG immunoreactivity was evaluated. TBG concentration was measured in 20 patients both by radioimmunoassay and by a T4-binding capacity assay, before, 4 and 10 months after a successful renal transplantation. Mean pretransplant TBG value measured by RIA was in the low normal range (1.60 +/- 0.14 mg/dl; normal limits 1.6-2.4 mg/dl). Twelve patients (60%) had TBG levels below 1.6 mg/dl (group I), while T4-binding capacity of TBG (TBC) measured in 7 of them was normal, so that the TBG/TBC ratio was characteristically reduced. The 8 remaining patients (group II) had TBG levels within or slightly above the normal range (mean value 2.26 +/- 0.17 mg/dl) and in the 5 tested patients, TBC and TBG/TBC ratio were normal. Four months after transplantation, mean TBG increased significantly in group I from 1.15 +/- 0.03 mg/dl before transplantation to 1.54 +/- 0.12 mg/dl (p less than 0.01). TBC increased also from 269 +/- 37.5 to 335 +/- 24 nmol/l (p less than 0.01) but to a significantly lesser extent than TBG (24% vs 48%, p less than 0.05). As a result, the TBG/TBC ratio returned to normal values, rising from 0.79 +/- 0.07 to 0.95 +/- 0.07 (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

不同甲状腺癌切除术治疗甲状腺癌患者的临床疗效分析

目的 探讨甲状腺癌切除术对甲状腺癌患者炎症指标分析.方法 将2019年1月至2021年9月在宣城市仁杰医院治疗的30例甲状腺癌患者根据手术方式分为两组,对照组使用甲状腺患侧叶切除+对侧次全切除术,观察组使用甲状腺患侧叶切除术.对比两组患者各项手术指标、并发症发生率、甲状腺激素指标、甲状旁腺激素(parathyroid ...     

二氧化碳气腹对术中血浆甲状腺素影响的观察

目的：探讨腹腔镜胆囊切除术（LC）中CO2气腹对甲状腺功能的影响。方法：全麻下胆囊切除术60例随机分为LC组（30例）和非腹腔镜组（30例）,于术前1日及术中不同时期抽取静脉血标本,用放射免疫法检测血浆甲状腺（TT3,TT4,FT3,FT4,rTs,TSH)的变化,结果：60例患者术前甲腺素水平均为正常。LC气腹后TT3,TT4,TSH升高（P＜0．01,与术前相比）,非腹腔镜者术中TT3有所一降。结论：LC术中甲状腺功能增强可能与CO2气腹有关。     

心内直视手术前后甲状腺激素监测

目的 为了了解体外循环（ＣＰＢ）手术前后甲状腺激素代谢的变化规律,及其与心功能变化的相关性。方法 以３６例患者ＣＰＢ术前２小时、术后１￣５天血浆甲状腺激素进行监测,另对其中１６例手术前后心功能变化进行动态监测,并观察它们之间的相互关系。结果 术前血浆甲状腺激素水平正常。ＦＴ３、ＦＴ４、ＴＴ３、ＴＴ４术后均呈现先下降后逐渐回升的变化趋势。ＴＳＨ术后第１天升至最高水平（Ｐ〈０．０５）,此后缓慢下降至术     

Alterations in thyroid hormones, cortisol, and catecholamine concentration in patients after orthopedic surgery

Changes in serum and plasma concentrations of thyroid hormones, cortisol, and catecholamines were measured simultaneously in 16 patients undergoing major elective orthopedic surgery. Blood samples were collected preoperatively and at 2, 6, 24, 48, 96, and 168 hr after surgery. A significant decrease in TT3 and FT3 and an increase in rT3 were noted after surgery. TT4 started to decrease 48 hr after surgery whereas FT4 showed no significant change over the same period of time. The concentration of TSH fell progressively after surgery reaching a nadir by Day 7. The concentrations of cortisol were increased markedly throughout the course after surgery. Adrenaline and noradrenaline levels were increased markedly during the first 24 hr postsurgery. Both the thyroglobulin and TBG together with albumin concentration values were decreased after surgery as compared to preoperative values. It is concluded that the changes in thyroid hormone levels after major elective orthopedic surgery seem to be independent of changes in plasma catecholamines and/or cortisol concentrations.     

Evaluation of Thyroid Function in Obese Dogs and in Dogs Undergoing a Weight Loss Protocol

Summary Obesity and weight loss have been shown to alter thyroid hormone homeostasis in humans. In dogs, obesity is the most common nutritional problem encountered and weight loss is the cornerstone of its treatment. Therefore, it is important to clarify how obesity and weight loss can affect thyroid function test results in that species. The objectives of this study were to compare thyroid function in obese dogs and in lean dogs and to explore the effects of caloric restriction and weight loss on thyroid hormone serum concentrations in obese dogs. In the first experiment, 12 healthy lean beagles and 12 obese beagles were compared. Thyroid function was evaluated by measuring serum concentrations of total thyroxine (TT4), free thyroxine (FT4), total triiodothyronine (TT3), thyrotropin (TSH), and reverse triiodothyronine (rT3) as well as a TSH stimulation test using 75 μg IV of recombinant human TSH. In the second experiment, eight obese beagles were fed an energy‐restricted diet [average 63% maintenance energy requirement (MER)] until optimal weight was obtained. Blood samples for determination of TT4, FT4, TT3, TSH and rT3, were taken at the start and then weekly during weight loss. Only TT3 and TT4 serum concentrations were significantly higher in obese dogs as compared to lean dogs. In the second experiment, weight loss resulted in a significant decrease in TT3 and TSH serum concentrations. Thus obesity and energy restriction significantly alter thyroid homeostasis in dogs, but the observed changes are unlikely to affect interpretation of thyroid function test results in clinics.