Early Versus Late Extubation in Myasthenia Gravis Patients
Early Versus Late Extubation in Myasthenia Gravis Patients
MYASTHENIA GRAVIS (MG) is an autoimmune disease characterized by varying degrees of muscle
 weakness and fatigability worsened with exertion and relieved with rest。Thymectomy plays an
 important role in the management of these patients because a consistent association between
 myasthenic and thymic pathology has been recognized.The need for prolonged mechanical
 ventilation in these patients after thymectomy is determined by their preoperative condition
 and various perioperative risk factors. Leventhal et al proposed a preoperative scoring
 system to predict the need for postoperative mechanical ventilation in myasthenic patients
 undergoing thymectomy based on the following 4 criteria: duration of MG, chronic respiratory
 disease, dose of pyridostigmine, and vital capacity. However, some investigators discovered
 that the Leventhal criteria may not be the sole benchmark and that other criteria such as
 severity of myasthenia,history of myasthenic crisis, and presence of thymoma may be more
 important in predicting the necessity for prolonged mechanical ventilation after thymectomy.
 Naguib et al described multivariate determinants of the need for postoperative ventilation
 after thymectomy in MG patients predominantly on the basis of pulmonary function tests. In
 addition, the prevalence and presentation of MG may be variable among different ethnic
 groups. However, there are very few large studies investigating the determinants of prolonged
 mechanical ventilation after thymectomy. The authors describe the parameters associated with
 prolonged mechanical ventilation after trans-sternal thymectomy at their institution.
Perioperative variables collected from the patient records were demographic data, duration of
 the disease,severity of the disease based on Osserman's classification, antiacetylcholine
 receptor (AChR) antibody positivity, preoperative drug therapy, history of preoperative
 myasthenic crisis, technique of anesthesia, drugs used for anesthesia, perioperative
 complications, and duration of postoperative mechanical ventilation. Even though the MG
 classification by the Myasthenia Gravis Foundation of America is widely accepted,disease
 severity was graded according to the Osserman and Genkins classification preoperatively as
 per the authors' institutional protocol.
Inclusion Criteria:

 -  myasthenia gravis patients after thymectomy

 Exclusion Criteria:

 -  not extubation