Numerous preclinical evidence has confirmed that most commonly-used general anesthetics can affect neurodevelopment of young animals adversely, causing both structural defect of brain and cognitive impairment. However, it is unclear at present whether such effect would also occur to children exposed to general anesthesia in their early life. Several observational clinical studies and one interventional clinical trial indicated that short-time general anesthesia less than 80 minutes might be safe to cognitive development. Concerning long-time and/or multiple anesthesia exposure, some studies supported its association with long-term cognitive defects, while other studies did not. These studies are mainly retrospective or ambirectional researches. We have designed a prospective, multicenter cohort study to examine the neurodevelopment of infants exposed to anesthesia before age 2 in the first year after surgery, and compare the neurodevelopment status of infants exposed to anesthesia less than 3 hours and those more than 3 hours. The Gesell Developmental Inventory (GDI) and several neuropsychological testing batteries will be used. The anticipated outcome of the study will add reliable evidence from Asians to elucidate the relationship of anesthesia and long-term neurodevelopment of infants.

Inclusion Criteria:

• Apgar score ≥ 8 at birth
• ASA level Ⅰ~Ⅲ
• Obtained written consent form from the infants' parents or guardians

Exclusion Criteria:

• Postmenstrual age ≤ 44 weeks, or postmenstrual age ≥ 144 weeks
• Severe cardiac, pulmonary, or neurologic disease
• Severe obstructive sleep apnea hypopnea syndrome
• History of dystocia and/or hypoxic ischemic encephalopathy
• Gestational age at birth ≤32 weeks
• Any known or suspected chromosomal abnormalities, abnormal development of vision or hearing, neurodevelopment retardation, or other known acquired or congenital abnormalities that might affect neurodevelopment
• Significant cardiovascular surgery, significant ENT surgery, or neurosurgery
• Malignant diseases that may reduce survival
• Taking part in other clinical trials in the last 3 months or at present

Eligible infants scheduled for elective surgeries under general anesthesia will be recruited in six medical centers in Shanghai, China. The medical centers include Huashan Hospital Fudan University, Shanghai Children's Medical Center, Children's Hospital of Fudan University, Children's Hospital of Shanghai, Shanghai Tenth People's Hospital, and Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University.