Endocrine disorders account for approximately 1.5% of all hospital emergency admissions in England; the majority are related to diabetes (Kearney and Dang, 2007). In the dental practice, hypoglycaemia is by far the most likely endocrine disorder to be encountered. Adrenal insufficiency may also occur.
The aim of this chapter is to understand the management of endocrine disorders.
Hypoglycaemia is normally defined as a blood glucose level < 3 mmol/L (Resuscitation Council (UK), 2012) and is usually associated with diabetes (particularly patients taking insulin). When attending for dental treatment, diabetic patients should eat as normal and should take their medication, e.g. insulin or oral hypoglycaemic agent, as prescribed (Resuscitation Council (UK), 2012; British Medical Association and Royal Pharmaceutical Society, 2012). If a meal is missed, then hypoglycaemia can occur (British Medical Association and Royal Pharmaceutical Society, 2012).
The exact incidence of hypoglycaemic episodes in the general population is unknown, as most are treated successfully at home and some, particularly those occurring at night, may not even be recognised. On average there are over 90,000 calls to the emergency services each year for hypoglycaemia (Sampson et al., 2006). In 2004/5 there were 8000 admissions to hospital in England due to hypoglycaemia (Kearney and Dang, 2007).
Hypoglycaemia accounts for approximately 22% of medical emergencies encountered in the dental surgery (Müller et al., 2008). Diabetic patients treated with insulin are most likely to become hypoglycaemic while attending for dental treatment (Resuscitation Council (UK), 2012).
The risks associated with hypoglycaemia are small, though altered level of consciousness can always lead to airway compromise. However, hypoglycaemia can cause an acute cerebral injury, leading to hemiplegia (Shirayama et al., 2004); a prolonged severe hypoglycaemic episode can even cause moderate to severe neuropsychological impairments (Kubiak et al., 2004).
Common causes of hypoglycaemia include:
- too much insulin;
- delayed or missed meal or snack;
- insufficient food, especially carbohydrate;
- unplanned or strenuous exercise;
- alcohol consumption without food;
Source: Diabetes UK (2013)
Medical causes of hypoglycaemia include:
- liver failure;
- Addison’s disease;
- pituitary insufficiency.
Source: Wyatt et al. (2012)
Nearly all hypoglycaemic episodes occur in patients who are prescribed insulin treatment, though episodes may rarely occur in patients prescribed sulphonylurea drugs (Shorr et al., 1997); these drugs, e.g. glibenclamide, augment insulin production (British Medical Association and Royal Pharmaceutical Society, 2012).
Consumption of alcohol can lead to hypoglycaemia several hours later; in addition, the effects of alcohol can mask the symptoms of hypoglycaemia.
The clinical features of hypoglycaemia vary from person to person, though they are often constant for an individual (Diabetes UK, 2013). Individuals may recognise different symptoms and these may change as the duration of diabetes increases (McLaren and Somerville, 1988).
Clinical features of hypoglycaemia can be classified as either autonomic (usually present first when the blood glucose is 3.3–3.6 mmol/L) or related to neuroglycopenia (usually present when the blood glucose is less than 2.6 mmol/L):
- Autonomic: sweating, hunger, hot sensation, anxiety, nausea and vomiting;
- Neuroglycopenia: fatigue, visual disturbance, uncoordinated and altered behaviour, drowsiness, confusion and if untreated convulsions and coma. (Turner and Wass, 2009; British Medical Association and Royal Pharmaceutical Society, 2012; Diabetes UK, 2013).
NB: in patients with chronic hyperglycaemia, the autonomic clinical features may be triggered at higher blood glucose levels.
Hypoglycaemia is a recognized complication of insulin therapy; at the onset most patients recognize the symptoms and are able to take remedial action but this hypoglycaemia awareness decreases over time so much so that after 20 years of insulin treatment 50% of these patients are unaware of their symptoms (Greenstein and Wood, 2011). The dental practitioner should therefore always be alert to the clinical features of hypoglycaemia.
Ideally blood glucose measurement should be undertaken in the dental practice. It is recommended that each dental practice has an automated blood glucose measurement device (Resuscitation Council (UK), 2012). The biomedical diagnosis of hypoglycaemia is a blood sugar less than 3.0 mmol/L (Resuscitation Council (UK), 2012). A suggested procedure for blood glucose measurement is described in Chapter 3.
- Assess the patient following the ABCDE approach described in Chapter 3. Treatment will depend upon the patient’s level of consciousness and degree of co-operation (Wyatt et al., 2012; Resuscitation Council (UK), 2012).
- If the patient’s consciousness level allows him to safely eat and drink, offer him the simplest available and quickly absorbed food or drink that contains carbohydrate, e.g. a glass of Lucozade or cola />