General anesthesia can be considered as a combination of hypnosis, antinociception and immobility. Explore the effect of three kinds of anesthesia,that is the total intravenous anesthesia, inhalation anesthesia and inhalation and intravenous anesthesia on stress reactions generated by patients with diabetes conducted gastric - bypass surgery , and choose a best way from three kinds of anesthesia to control stress reaction of diabetics. After selecting the appropriate anesthesia method, assess the effect of dexmedetomidine on controlling stress response from diabetics undergoing laparoscopic gastric-bypass surgical.

Research content and indicators

1. Preparation of serum: 3ml of blood were taken before induction of anesthesia (after entering the operating room), surgery began 1h, surgery began 2h, 24h after surgery, and placed at dry tube, centrifuged for 10min at 3000g after placing at room temperature for 2h , the resulting supernatant was subpassaged in tube, stored at -20℃ until analysis.
2. Indicators to detect in serum contained Tumor Necrosis Factor-α, Interleukin-6, Interleukin-10, plasma glucose, cortisol,insulin and c-peptide.
3. Record the vital signs.

Inclusion Criteria:

• American Society of Anesthesiologists（ASA）Ⅰ ~ Ⅱpatients
• Type 2 Diabetes Mellitus patient undergoing Laparoscopic Gastric Bypass surgery
• between 18 and 60 years of age

Exclusion Criteria:

• A history of cardiopulmonary disease, liver and kidney dysfunction, abnormal coagulation
• Thyroid disease