Effect Of Dexmedetomidine On Perioperative Blood Glucose Regulation And Related Hormones In Non-Diabetic Patients Undergoing Gastrointestinal Malignant Tumor Resection

PurposeHyperglycemia,as a common manifestation of perioperative stress response,can increase the incidence of complications such as postoperative infections and cardiovascular and cerebrovascular events.Dexmedetomidine is a highly selective ?2 adrenergic receptor agonist that is widely used in clinical anesthesia.It can decrease blood glucose by inhibiting stress and sympathetic responses.Meanwhile,it can also increase blood glucose by inhibiting insulin secretion at stimulation on a2 adrenaline receptors of the pancreatic ? cells.There have been few reports about the optimal dose of dexmedetomidine on perioperative blood glucose levels and the related hormone secretion under anesthesia.Due to severe trauma and long operation time of gastrointestinal malignant tumor resection,patients are often in a strong stress state,which may lead to hyperglycemia.This study is carried out to evaluate the optimal dose of dexmedetomidine for perioperative blood glucose regulation in non-diabetic patients with gastrointestinal malignant tumors resection,and to explore the specific effects of dexmedetomidine on blood glucose-related hormonesMethodsOne hundred non-diabetic patients who underwent elective gastrointestinal malignant tumor resection were randomly divided into 4 groups(25 cases in each group):dexmedetomidine bolus 1 ?g/kg+ maintenance dose 0.25 ?g·kg-1·h-1(group D1),bolus 1?g/kg+0.5 ?g·kg-1·h-1(group D2),bolus 1 ?g/kg+1 ?g·kg-1·h-1(group D3)and control group(group C).Dexmedetomidine bolus dose 1 ?g/kg were intravenously infused with the time of 10 min before general anesthesia induction and maintained at rates of 0.25,0.5 and 1 ?g·kg-1·h-1,respectively,in groups D1,D2 and D3,till approximately 30 min before surgery finish.Group C was given intravenous saline 50 ml/h for 10 min,followed by continuous infusion of 10 ml/h till approximately 30 min before surgery finish.All patients were maintained with intravenous infusion of propofol and remifentanil and inhalation of sevoflurane 1 MAC.During the whole anesthesia period,the rates of propofol and remifentanil were adjusted according to the Narcotrend,and the anesthesia depth was maintained at stages of D2-E1(index of 20-46).Levels of blood glucose,insulin,glucagon,cortisol and catecholamine were measured before intravenous infusion of dexmedetomidine(T1),1 h after the beginning of surgery(T2),at the end of surgery(T3),and 1 h in PACU(T4).Length of surgery,extubation time,doses of propofol and remifentanil,and vasoactive drugs were recorded.Perioperative adverse reactions such as severe bradycardia,severe hypotension,and respiratory depression were recorded.Postoperative pulmonary infection,total peritoneal drainage 2 days after surgery and hospitalization were also recorded.Results(1)No significant differences were observed in the demographic characteristics or duration of surgery between the four groups(P>0.05).(2)Changes of blood glucose levels at each time points in the four groups Compared with Ti,blood glucose at T4 increased significantly in group C(P<0.01).Blood glucose at T2-4 also increased significantly compared with those at Ti in groups Di,D2,and D3(P<0.01),with no differences were observed among T2-4(P>0.05).Compared with group C,blood glucose at T4 were significantly lower in groups Di,D2,and D3(P<0.01),but significantly higher at T2 and T3 in groups D2 and D3(P<0.05).(3)Changes of glucose related hormones in the four groupsa)There was no significant difference in insulin between the four groups(P>0.05).b)Compared with T1,Glucagon at T2 in the four groups,at T3 in groups C and Di,and at T4 in groups Di,D2,and D3 decreased significantly(P<0.05).Compared with group C,Glucagon at T4 in group Di,D2 and D3 decreased significantly(P<0.05).c)Compared with Ti,Cortisol at T2 in the four groups decreased significantly(P<0.05);Cortisol at T3 in groups D2 and D3 decreased significantly(P<0.05).Compared with group C,Cortisol at T4 in groups D1,D2,and D3 decreased significantly(P<0.05).d)Compared with Ti,norepinephrine at T2 in group C increased significantly(P<0.05).Compared with T2,norepinephrine at T4 in group C decreased significantly(P<0.05).Compared with group C,norepinephrine at T2 in groups D1,D2 and D3 decreased significantly(P<0.05).e)Compared with T1,epinephrine at T2 in group C increased significantly(P<0.05);epinephrine at T3 and T4 in group D3 decreased significantly(P<0.05).Compared with group C,epinephrine at T2 in groups D1,D2,and D3 decreased significantly(P<0.05);epinephrine at T3.in groups D2 and D3 decreased significantly,and at T4 in group D3 decreased significantly(P<0.05).f)Compared with T1,dopamine at T2-4 in group D3 decreased significantly(P<0.05).Compared with group C,dopamine at T2-4 in group D3 decreased significantly(P<0.05).(4)The required doses of propofol and remifentanil were significantly lower in groups Di,D2,and D3 compared with those in group C(P<0.01).Ephedrine(P<0.05)and atropine(P<0.01)use were greater and extubation time was longer in group D3 compared with the other three groups(P<0.01).No significant differences were found in the phenylephrine dosage used among the four groups.(5)The incidence of severe bradycardia was higher in group D3 than in group C(P<0.05).No significant differences were found in the incidence of severe hypotension,total abdominal drainage volume at 2 days after surgery,or hospital stay among the four groups(P>0.05).ConclusionsDexmedetomidine,with a loading dose of 1 ?g/kg followed by a maintenance dose of 0.25?g·kg-1·h-1,can regulate perioperative blood glucose levels well in non-diabetic patients undergoing gastrointestinal malignant tumor resection.This methodology has no significant effect on Ins level,can reduce Gluc and Cor levels after surgery and NE and E levels during surgery,which can reduce doses of general anesthetic drugs without extending extubation time.