Perioperative Management in a Patient With Type 1 Diabetes Mellitus Who Presented Severe Hypoglycemia During Dental Implant Surgery

A Case Report

Hajime Shimoda; Tetsu Takahashi


BMC Oral Health. 2018;18(204) 

In This Article


In patients with type 1 DM, pancreatic β-cells are destroyed, and endogenous insulin secretion capacity is depleted.[2] In comparison with type 2 DM, type 1 DM is characterized by poor glucose tolerance owing to insufficient secretion of endogenous insulin. This situation can promote the hypersecretion of catabolic hormones during invasive surgery or anesthesia and initiate a neuroendocrine stress response. The current case supports that even in the perioperative management for oral surgical outpatients, oral surgeons and dental anesthesiologists need to keep in mind the appropriate continuous administration of insulin with a glucose-electrolyte infusion and careful blood glucose monitoring.[3]

From the viewpoint of prevention of diabetic complications, including ketoacidosis, development of systemic vascular lesions, and compromised infections or protracted wound healing, it is essential to conduct a systemic assessment based on diagnostic and prognostic criteria. Regarding preoperative blood glucose control for diabetic surgical patients, such assessments comprise negative urinary ketone bodies, HbA1c level lower than 7%, and a fasting blood glucose level lower than 130 mg/dL.[4] At blood glucose levels above 200 mg/dL, bacterial infectivity is promoted due to impairment in neutrophil phagocytosis,[5] followed by postoperative wound healing failure. In addition, to avoid unexpected hypoglycemia and postoperative infections in oral surgical patients, it is also recommended that blood glucose level should be maintained at approximately 150 mg/dL.[6] If HbA1c is lower than 7% but exceeds 6.2% (upper limit of normal range), premedication with antibiotics is considered necessary owing to an increased risk of focal infections.[7]

As shown in the present case, medical control of type 1 DM is difficult owing to highly variable diurnal or day-to-day variation in blood glucose levels. Furthermore, even immediately after typical food intake, a large variation of blood glucose may be irregularly triggered by psychosomatic stress related to dental surgical procedures. On the other hand, to differentiate hypoglycemic symptoms from other clinical signs, it is important to be well acquainted with some principal clinical symptoms characteristic of hypoglycemia as follows. If blood glucose level decreases below 70 mg/dL, sympathetic stimulation-related symptoms such as abnormal hunger, anxiety, palpitation, cold sweat, and/or tremor can be developed in conjunction with catecholamine hypersecretion. In a hypoglycemic situation, when blood glucose level is below 50 mg/dL, nausea, malaise, drowsiness, headache, delirium, visual abnormality, and/or bradycardia may appear owing to suppression of central nervous function. Hypoglycemia below 30 mg/dL results in convulsions and/or coma due to cerebral dysfunction.[8,9]

During the present perioperative management, in consideration of diabetes, an electrolyte solution containing rapid acting insulin was prepared according to the sliding scale of our hospital for blood glucose values above 200 mg/dL. In the present patient, who had experienced repeated hypoglycemic attacks, signs of hypoglycemia, without any sympathetic symptoms, may be specifically recognized only when blood glucose level decreases below 30 mg/dL. Accordingly, prompt subcutaneous injection of glucagon[10] may be also required, based on the appearance of conscious disturbance, which is a hypoglycemic sign. Thus, to ensure glycemic control, we recognized that we should have preoperatively prepared the appropriate administration of insulin with an electrolyte-combined infusion of glucose.

The application of felypressin as a vasoconstrictor for local anesthesia in the present patient was judged to be appropriate to avoid a hypertensive emergency and hyperglycemia due to extrinsic adrenaline. Moreover, considering that systemic blood flow disorders in patients with diabetes and hypertension may extend to the weakened microvessels of periodontal tissues,[11] we were concerned about the latent risk of gingival ulceration resulting from strong vasoconstriction.

Patients undergoing dental implant surgery are likely to have various systemic underlying diseases such as DM or hypertension. Consequently, the clinical insights and skills regarding medication are essential to practice safe perioperative management of blood glucose or hemodynamics. Furthermore, patients with type 1 DM may not manifest typical hypoglycemia symptoms, despite a severely low blood glucose level. In this regard, we reaffirmed the importance of a more careful time-series evaluation of blood glucose in perioperative glycemic management for the present patient undergoing dental implant surgery.

In the light of the above viewpoints, it seems more difficult to manage a patient such as the present case owing to limited use of cardiorespiratory monitoring devices and limited care or medication for an emergency involving severe hypoglycemic attack or unstable hemodynamics under normal private practice conditions. Therefore, we suggest that it might be advisable to operate on such a patient in an institution that can provide satisfactory cardiorespiratory monitoring equipment and medication, taking into consideration the high-risk complications including severe hypoglycemia and hypertension.

In conclusion, although the surgical procedure for this patient with type 1 DM was less invasive and limited to the area of implant manipulation, within the mandibular region of the two molars, compared to implant surgery that spans the entire lower jaw, the present case suggests the necessity of examining possible signs of hypoglycemia-precipitated acute symptoms in patients with DM. This is particularly true in patients with type 1 DM who are undergoing relatively highly-invasive oral surgical manipulation such as commonly performed dental implant surgery spanning the entire jaw. It is also important to accomplish appropriate emergency care, differentiating hypoglycemic symptoms from other clinical signs. Therefore, dental anesthesiologists as well as oral surgeons are specifically required to provide principal cardiorespiratory monitoring and carry out careful systemic management particularly for a medically compromised patient such as the one we have presented with type 1 DM who may experience complications including severe hypoglycemia and unstable hemodynamics.