ObjectiveTo explore the risk factors of myasthenic crisis after thymectomy (MCAT) for patients with myasthenia gravis (MG). MethodsWe searched PubMed, EMbase, The Cochrane Library (Issue 8, 2015), Web of Knowledge, CBM, CNKI and WanFang Data from inception to August 31, 2015, to collect case-control studies and retrospective cohort studies about the MCAT for patients with MG. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was performed using Stata 13.0 software. ResultsA total of 17 studies involving 394 patients with myasthenic crisis and 1642 controls were included. Of the 17 studies, 11 were retrospective cohort studies and 6 were case-control studies. The results of meta-analysis showed that:a) univariate analysis indicated that history of myasthenic crisis (OR=8.05, 95%CI 5.80 to 11.15, P<0.01), bulbar symptoms (OR=5.10, 95%CI 3.01 to 8.67, P<0.01), preoperative severity of gravis (Osserman-stage) (OR=10.55, 95%CI 7.28 to 15.30, P<0.01), postoperative pulmonary infection (OR=10.77, 95%CI 3.88 to 29.95, P<0.01), thymoma (OR=2.37, 95%CI 1.50 to 3.75, P<0.01), dose of pyridostigmine (MD=0.45, 95%CI 0.29 to 0.62, P<0.01), AChRAb level >100 nmol/L (OR=12.14, 95%CI 4.80 to 30.73, P<0.01) and operation time (MD=0.57, 95%CI 0.26 to 0.88, P<0.01) were the risk factors of MCAT; b) multivariate analysis showed that, history of myasthenic crisis (OR=5.06, 95%CI 2.30 to 11.14, P<0.01), bulbar symptoms (OR=5.21, 95%CI 2.62 to 10.35, P<0.01), preoperative severity of gravis (Osserman-stage) (OR=5.82, 95%CI 2.60 to 13.04, P<0.01) and AChRAb level >100 nmol/L (OR=8.38, 95%CI 3.31 to 23.08, P<0.01) were the independent risk factors of MCAT. ConclusionThe independent risk factors of MCAT for patients with MG are history of myasthenic crisis, bulbar symptoms, preoperative severity of gravis (Osserman-stage) and AChRAb level >100 nmol/L.
Objective To summarize experiences of surgical treatment and long-term results of myasthenia gravis (MG). Methods Two hundred thirty-six patients underwent thymectomy for MG in our department from Jan.1978 to Dec. 2002. The perioperative management, relative factors of postoperative crisis and long-term results were analysed. Results In 236 patients postoperative crisis took place in 44 cases accounted for 18.6%. The occurrence of postoperative crisis was related to preoperative management, modified Osserman clinical classification and combination with thymoma. Three cases died in the postoperative periods. Among them, one died of acute respiratory distress syndrome induced by aspiration and the other died of crisis. The effective rate in 1, 3, 5 years was 84.6%, 91.0% and 89.0% respectively. Conclusions Thymectomy for MG is safe and effective. Delayed extubation could decrease the needs of tracheotomy in patients with high risk factors for postoperative crisis. The partial sternotomy approach is less traumatic but the long-term effects of surgery are identical to those reported by the most authors.
Surgery is an important treatment for the anterior mediastinal disease. With the rapid development of minimally invasive techniques, complete resection of the lesion in most patients with thymic disease can be achieved through thoracoscopic surgery. Practice has proved that the three-port resection of anterior mediastinal thymus disease via the subxiphoid approach is an ideal surgical method for the treatment of anterior mediastinal thymic tumors at present, which has strong popularization and popularity and can benefit the patients. The procedure focuses primarily on the anterior and upper mediastinum and can thoroughly expose the anatomy of the mediastinum and both sides, with minimal intraoperative bleeding, high safety, minimal trauma and postoperative pain, and a short hospital stay. It has clear advantages over conventional thoracic open-heart surgery and transversal resection. However, the surgical approach and field of view, and intraoperative precautions of this procedure are completely different from those of previous thoracoscopic procedures, and from the subxiphoid single-port approach adopted by other centers. Based on 10 years of surgical experience at our center, a modular mode of surgical operation has been developed and its procedure has been standardized. This paper will share and discuss relevant operational points and experiences.
ObjectiveTo investigate the perioperative safety of patients with myasthenia gravis who take high doses of oral corticosteroids. MethodsA retrospective analysis was conducted on the clinical data of patients with myasthenia gravis who received oral corticosteroids and underwent thoracoscopic thymectomy at the Department of Thoracic Surgery, the University of Hong Kong-Shenzhen Hospital from April 2013 to October 2019. Patients were divided into a high-dose steroid group and a medium-to-low dose steroid group based on the dosage of oral steroids, and the clinical data of the two groups were compared. ResultsA total of 102 patients were included, including 19 (18.62%) males and 83 (81.37%) females, with an average age of (32.25±9.83) years. All patients in both groups successfully completed the surgery without major intraoperative bleeding, conversion to open chest surgery, delayed extubation, severe infection, or perioperative death. The daily oral steroid dose for the high-dose steroid group was (35.81±4.29) mg, and for the medium-to-low dose steroid group it was (15.29±2.17) mg. There was no statistical difference in the operation time [(124.69±23.51) min vs. (117.89±21.46) min, P=0.172] and intraoperative blood loss [(21.19±3.48) mL vs. (20.56±3.41) mL, P=0.419] between the two groups. Postoperatively, 12 (11.76%) patients developed complications: one patient of myasthenic crisis (medium-to-low dose steroid group), which was improved after short-term respiratory support and intravenous immunoglobulin treatment; 11 patients of respiratory/swallowing difficulties (9 in the low-dose steroid group and 2 in the high-dose steroid group), which were improved after anticholinergic treatment to reduce oral secretions and sputum suction, and the patients were discharged smoothly. There was no statistical difference in the incidence of postoperative complications between the two groups (P=0.637). ConclusionOn the basis of good perioperative management, it is safe and feasible for patients with myasthenia gravis who take high dose of oral steroids to undergo thymectomy, and they have the same perioperative safety as patients with medium-to-low dose steroids.
ObjectiveTo investigate the effect of noninvasive ventilation (NIV) in patients with myasthenic crisis after thymectomy. Methods31 myasthenic crisis patients after thymectomy who initially used NIV,admitted in the First Affiliated Hospital of Guangzhou Medical University between January 2011 and June 2013,were analyzed retrospectively.They were assigned to two groups according to the successful application of NIV or not,with 13 patients in the NIV success group and 18 patients in the NIV failure group.The related factors including gender,age,APACHEⅡ score when admitted to ICU,the results of blood gas analysis before NIV,thymoma or not,the history of myasthenic crisis,the history of chronic lung disease,and minute ventilation accounted for the largest percentage of predicted value (MVV%pred)were analyzed. ResultsThere were no significant differences in age,gender,or APACHEⅡ score between two groups (P>0.05).The PaCO2 in the NIV success group was lower than that in the NIV failure group.The preoperative MVV%pred in the NIV success group was higher than that in the NIV failure group.There were no significant differences between two groups in pH,PO2,thymoma or not,the history of myasthenic crisis,or the history of chronic lung disease (P>0.05).If using the 45 mm Hg as the cut-off value of PaCO2 and 60% as the cut-off value of MVV%pred,the incidence of PaCO2<45 mm Hg and the incidence of MVV%pred>60% were higher in the NIV success group than those in the NIV failure group (84.6% vs.33.3%, P<0.05;100% vs. 55.6%,P<0.05).Logistic regression analysis revealed that PaCO2<45 mm Hg was an independent influence factor for successful application of NIV in patients with myasthenic crisis after thymectomy. ConclusionPaCO2<45 mm Hg can be a predictor of successful application of NIV in patients with myasthenic crisis after thymectomy.For the patients underwent NIV whose PaCO2<45 mm Hg or MVV%pred<60%,the clinician should predict the possibility of failure and prepared for intubation.
ObjectiveTo compare clinical effects of enlarged thymectomy for the treatment of myasthenia gravis (MG) complicated with thymoma via subxiphoid and subcostal arch thoracoscopic resection versus median sternotomy resection. MethodsWe retrospectively analyzed the clinical data of patients with MG complicated with thymoma admitted in Tangdu Hospital of the Air Force Military Medical University between December 2011 and December 2021. Patients who underwent subxiphoid and subcostal arch thoracoscopic enlarged thymectomy were allocated to a SR group, and patients who underwent median sternotomy enlarged thymectomy were allocated to a MR group. Perioperative outcomes were compared between the two groups. ResultsA total of 456 patients were collected. There were 51 patients in the MR group, including 30 males and 21 females aged 23-66 (49.5±11.8) years. There were 405 patients in the SR group, among whom 51 patients were matched to the MR group by propensity score matching, including 28 males and 23 females aged 26-70 (47.2±12.2) years. The operations were accomplished successfully in all patients, and no conversion to thoracotomy occurred in the SR group. The SR group had advantages in the operation time, intraoperative blood loss, chest drainage duration, hospital stay time, patients’ satisfaction level, pain score and complications (all P<0.05). No statistical difference was found in the number of intraoperative lymph node dissection stations, number of intraoperative lymph nodes dissected or remission of MG between the two groups (P>0.05). ConclusionSubxiphoid and subcostal arch thoracoscopic enlarged thymectomy and lymphadenectomy is a safe, effective and feasible minimally invasive procedure for the treatment of MG complicated with thymoma.
Objective To evaluate the risk factors affecting the prognosis in patients with myasthenia gravis after thymeetomy. Methods Therapeutic effects were evaluated with Relative Counting Method in 136 cases with myasthenia gravis who receivingthymectomy. Six clinical factors including sex, age, preoperative course, et al. were converted into quantitative parameters and used for analysis. Cumulative logit model for ordinal response was employed to investigate the therapeutic effects of various factors. Results Sex, age and preoperative course exerted significant effects on postoperative prognosis in patients with myasthenia gravis, while clinical subtype, pathological changes and preoperative administration of cholinesterase inhibitors had no significant impact on therapeutic effects. Conclusion Some factors may lead to the remission and improvement in postoperative patients with myasthenia gravis, therefore, they should be included for the evaluation of prognosis. Early diagnosis and early thymeetomy may improve the therapeutic effects and shorten the duration of amelioration.
ObjectiveTo investigate the expression of α7 nicotinic acetylcholine receptor (α7 nAChR) in thymocytes of patients with myasthenia gravis (MG) and its effect on cytokine secretion and T cell proliferation. MethodsPatients with MG who underwent expanded thoracoscopic thymectomy in the Comprehensive Diagnosis and Treatment Center of the Henan Provincial People’s Hospital from June 2021 to June 2022 were selected and allocated to a MG group. Patients who underwent partial thymectomy to expose the surgical field during the cardiac disease surgery from June 2021 to September 2022 in the Department of Adult Cardiac Surgery of Fuwai Huazhong Cardiovascular Hospital were selected as the control group. Thymic single cell suspensions were prepared from MG and control groups, and the expression of α7 nAChR in thymocytes of the two groups was detected by real-time polymerase chain reaction and Western blotting. Then CD3/CD28 monoclonal antibody coupled with magnetic beads was used to induce T cell activation, and the levels of cytokines interferon-gamma (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), IL-6, IL-10, IL-17, and IL-21 in thymocytes of the two groups were detected by enzyme-linked immunosorbent assay (ELISA). The activated T cells of the MG group were divided into a blank control group, an α7 nAChR antagonist group, and an α7 nAChR agonist group according to different treatment methods. After 72 hours of culture, IFN-γ, TNF-α, IL-4, IL-6, IL-10, IL-17, and IL-21 expression levels in the culture supernatant were measured by ELISA. Afterwards, CD4-PE and CD8-APC antibodies were added, and the proliferation of T cell subsets was detected by flow cytometry. ResultsA total of 10 MG patients were collected, including 3 males and 7 females with an average age of 19.25±6.28 years; and 15 control patients were collected, including 6 males and 9 females with an average age of 26.18±6.77 years. Compared with the control group, the mRNA and protein levels of α7 nAChR in the thymocytes of MG group were decreased, and the expression levels of IFN-γ, TNF-α, IL-4, IL-6 and IL-21 in the supernatant were increased (P<0.05), but there was no statistical difference in the expression of IL-10 and IL-17 (P>0.05). The cell-culture experiment showed that compared with the blank control group, the levels of IFN-γ, TNF-α, IL-6 and IL-21 secreted by T cells in the α7 nAChR antagonist group were increased (P<0.05), while they were decreased in the α7 nAChR agonist group (P<0.05). There was no statistical difference in the secretion levels of IL-4, IL-10 or IL-17 among the three groups (P>0.05). CD4+ T and CD8+ T cells in the α7 nAChR agonist group were significantly less than those in the blank control group and α7 nAChR antagonist group (P<0.001), while they were significantly more in the α7 nAChR antagonist group than those in the blank control group (P<0.001).ConclusionThe expression of α7 nAChR in thymocytes of MG patients is decreased, and α7 nAChR may be involved in the inflammatory response in thymocytes and thus in thymic function.