Currently, no fundamental treatment has been determined for GSD type I, and diet is the mainstay of treatment. The main goal is to maintain blood glucose levels and prevent metabolic abnormalities, which requires diet therapy (small frequent meals every 3–4 h, lactose and sucrose elimination, and fructose restriction), special formula for GSD treatment (low-fat milk with lactose and fructose removed) and uncooked cornstarch, and frequent or continuous nighttime supplementation [13,14,15,16]. In patients with GSD Ia, glycogenolysis and glycogenesis are accelerated during hypoglycemia; however, glucose is not synthesized from glucose-6-phosphate (G6P), which flows into the glycolytic system and is converted to lactate, resulting in hyperlactatemia [5]. Perioperatively, hypoglycemia due to restricted oral intake, large fluctuations in blood glucose levels with surgical invasiveness, and enhancement of glycogenolysis and lactic acid production by catecholamines are induced. Although close perioperative monitoring of blood glucose and lactate levels before elective surgery is important for the management of GSD type I [13], appropriate glucose dosage to maintain perioperative blood glucose and lactate levels in patients with GSD is still unknown.

Several studies reported perioperative glucose doses for patients with GSD type Ia (Table 1). Despite continuous glucose infusion in all of those patients, four patients developed lactic acidosis and hypoglycemia perioperatively [9, 11], and five developed lactic acidosis without hypoglycemia [7, 10, 11].

In this case, glucose infusion had been started the day before surgery and continued during and after surgery. Despite normal blood glucose levels, severe acidosis occurred, which might be induced by the following mechanism. Accumulated G6P due to G6Pase deficiency is metabolized to pyruvate via glycolysis. Although pyruvate is normally consumed by entering into the citric acid cycle in mitochondria, mitochondrial dysfunction in patients with GSD Ia may lead to lactic acid production from pyruvic acid [17]. Additionally, perioperative stress-induced hormone secretion may lead to increased G6P production from glycogen. Another possible cause of perioperative severe acidosis is insufficient perioperative glucose dosing relative to the requirements of the perioperative organism. According to previous reports, glucose doses were 3.3–6.7, 6.0–9.8, and 6.6 mg/kg/min before, during, and after surgery [9]. Although lactic acidosis might have been prevented by a larger dose of perioperative glucose in our case, it should be administered from a central venous line and whether an invasive procedure for inserting it is required in such a minimally invasive oral surgery is unclear.

Diaphragmatic elevation by the head-down position in addition to preexisting hepatomegaly would have limited tidal volume [10], leading to hypercapnia and worsening of acidosis in this case. Consequently, the partial pressure of carbon dioxide in the blood increased, which may have contributed to the worsening of the acidosis.

Bleeding tendency is a problem in patients with GSD type I because of impaired platelet function [4, 13]. Bleeding complications were reported in 23% of patients with GSD I, and perioperative bleeding tendency should be noted [13]. In this case, oral intubation was performed instead of nasal intubation because of frequent epistaxis. No abnormal postoperative bleeding was observed.

Patients with GSD Ia often present with hypertriglyceridemia, and pancreatitis is an important complication [18, 19]. Acute pancreatitis is reported after general anesthesia with propofol in a patient with GSD Ia [6]. Because acute pancreatitis may be caused by propofol in patients with hypertriglyceridemia [20], its use should be avoided in such patients. We used thiamylal instead of propofol with sevoflurane, resulting in no postoperative complications including pancreatitis.

A few studies have reported the perioperative management of GSD because of its rarity and low prevalence; thus, more studies are needed to determine the appropriate perioperative management for patients with GSD, including glucose infusion during fasting. Standard perioperative management must be established to manage complications and improve the care of patients with GSD undergoing surgery or receiving intensive care.