[Influence of pre-operative fasting time on blood glucose in older patients]

This study was performed to identify changes in blood glucose at preoperative fasting time in surgical patients over 60 yr.

Data collection was performed from July, 2008 through July, 2009. Participants consisted of 80 nondiabetic surgical patients. Blood glucose was checked from 3 to 5 times. The 5 times were 2-hr fasting on the pre-operative day (T1, n=80), 8 hr (T2, n=80), 10 hr (T3, n=17), 12 hr (T4, n=34) and 14 hr fasting on the day of the operation (T5, n=29).

Of the patients, 27.5% had a blood glucose level of less than 79 mg/dL at T2; 17.6% at T3; 32.4% at T4; and 17.2% at T5. Mean blood glucose levels were 93.8 mg/dL at T1; 88.4 mg/dL at T2; 91.7 mg/dL at T3; 87.4 mg/dL at T4: and 94.1 mg/dL at T5. Blood glucose was the lowest at T2 (p<.001).

As 17.6-32.4% of the patients showed the blood glucose level of less than 79 mg/dL at 8-14 hr pre-operative fasting, the authors recommend that surgical patients >60 yr-of-age be observed for hypoglycemia during pre-operative fasting of more than 10 hr and that surgical patients >60 yr-of-age with risks for hypoglycemia be scheduled for operation within 10 hr preoperative fasting.