Prehospital Hypoglycaemia
Written by: Iqra Rasheed
Edited By: Adam Jones
Prehospital Hypoglycaemia Introduction
Prehospital Hypoglycaemia is life-threatening, which is associated with unusual low glucose levels in the blood and is usually lower than 4 mmol/L. Hypoglycaemia in a prehospital environment consists of the quick identification and management to avoid the development of such complications, such as seizures. Emergency responders and paramedics are a key factor in determining and treating hypoglycaemia before reaching a hospital.
Epidemiology
The incidence of hypoglycaemia in type 1 diabetes patients is around 62 per 100 patients with greater incidence occurring among patients who are subjected to intensive insulin regiment. Conversely, it is less frequent in type 2 diabetes, partly because most of the available treatments such as metformin do not lead to low blood sugar. The incidence of diabetes type 2 was generally reported as 35 episodes per 100 patients, and there is no significant difference between women and men.
According to the study conducted by Zaccardi et al. (2016), the rate of hospitalisation caused by hypoglycaemia in England rose by 39 percent within one decade. Nevertheless, after correcting by the increasing rate of diabetes, the rate of admission decreased. Moreover, the hospitalisation costs, death rates, and rehospitalisation related to hypoglycaemia also reduced. Although there are records of these improvements, the rising prevalence of the number of older people and those with diabetes indicates that more should be done to prevent hypoglycaemia and handle it better.
Pathophysiology
Hypoglycaemia is the condition of low blood sugar beneath the requirement of the organism particularly the brain to provide a significant source of energy that is virtually left without glucose. When blood glucose levels start to decrease, a stream of counter-regulatory hormone responses is triggered to rebalance them.
The initial reaction is the suppression of insulin to enable the liver to discharge the reserved glucose (glycogenolysis) and start manufacturing new glucose (gluconeogenesis). When the level of glucose drops further, the pancreas releases glucagon and this makes the liver to produce more glucose. When this is not enough then adrenal glands secrete a hormone known as epinephrine (adrenaline) that increases our blood sugar and decreases the uptake of glucose by our tissues.
In severe and prolong hypoglycaemia other hormones like the cortisol and growth hormone are released to maintain energy balance and glucose production.
Prehospital Hypoglycaemia could be due to over insulin (usually in diabetics), skipping meals, alcohol, liver failure, sepsis, adrenalin deficiency, or drugs. If not corrected, it may cause brain dysfunction, change of mental status, seizures or lose consciousness.
Causes Of Hypoglycaemia
Prehospital Hypoglycaemia may be caused by a variety of conditions, among them:
Too much insulin or medicines
Medicines such as sulfonylureas taken by a person with diabetes.
Missing or skipping meals
This causes low blood sugar especially when associated with diabetes medication.
Alcohol consumption
which may lessen the capacity of the liver to liberate glycogen.
Extreme sickness or infection (sepsis)
Which may interfere with glucose equilibrium.
Liver disease
Which attacks the storage and production of glucose.
Adrenal insufficiency
Lessens the hormones which assist in the management of blood sugar.
Risk Factors Of Hypoglycaemia
Risk factors of hypoglycaemia include:
- Diabetes Type 1 or Type 2– particularly those taking insulin or sulfonyl urea
- Older Age -Because of the decrease in physical reserve and the time delay in identification of the symptoms
- Cognitive Impairment– can interfere with awareness of the symptoms of hypoglycaemia or the use or drugs in the right manner
- Polypharmacy– more potential drug interactions and mistakes during treatment with drugs
- Kidney Disease impaired insulin and hypoglycaemic clearance
Signs & Symptoms Of Hypoglycaemia In Prehospital
Hypoglycaemia has various symptoms that develop (depending on the further decrease of blood glucose levels). The presence of stress hormones (mostly adrenaline) in the body produces early symptoms whereas severe symptoms demonstrate poor supply of glucose to the brain.
- Sweating
- Tremor or shakiness
- Hunger
- Fast heartbeat (Palpitations)
- Anxieties or nervousness
- Mix up or inability to focus
- Slurred speech
- Grumpiness or Abnormal behaviour
- Seizures
- Fainting injury
Note: In other patients especially patients with hypoglycaemia unawareness, normal warning signs can be limited or non-existent. This is more frequent in patients who have diabetes with long histories or have frequent hypoglycaemic attacks.
History Of Prehospital Hypoglycaemia
It is crucial to have infection prevention and control measures for limiting the transmission of flu specifically in schools, healthcare settings and workplaces. The key measures would involve:
Presenting symptoms
Ask about signs such as, shakiness sweating, dizziness, confusion, slurred speech, altered behaviour or Clarify the severity, timing and current condition.
Diabetes history
Obtain the type of diabetes that the patient has (Type 1 or 2), the method of its treatment (insulin, oral drugs), and previous occurrences of hypoglycaemia.
Medication use
Search for recent insulin or sulfonylurea medication, along with other medicines that can cause low-blood sugar level or interfere with the diabetes management.
Dietary intake
Inquiries about the missed meal or when patient took last meal particularly among patients on glucose-reducing medicines. Check fluid and alcohol consumption.
Other medical diseases
Ask about, kidney dysfunction, liver disease, adrenal insufficiency, or sepsis, any of which can interrupt with glucose regulation.
Previous episodes
Enquire as to whether the patient has had a previous history of hypoglycaemia and how they have coped with it and whether they develop symptoms or experience hypoglycaemia unawareness.
Assessment Of Prehospital Hypoglycaemia
Initial observation
Evaluate level of awareness, skin temperature, perspiration and activity. Observe behavioural disorders, agitation, or the inability to respond.
Vital signs
Measure, heart rate, respirations blood pressure and oxygen saturation. Assess whether there are the symptoms of the hypotension, development of bradycardia, or respiratory compromise.
The measurement of blood glucose
To measure capillary blood glucose, use a glucometer. Verify hypoglycemia (less than 4.0 mmol/L or less than 72 mg/dL, depending on local protocol).
Neurological status
Evaluate for altered mental status, slurred speech, seizures, or focal deficits. Use Glasgow Coma Scale or other scale named AVPU as appropriate.
Medication check
Look at insulin pens, glucose reduces pills, or a medical ID that labels diabetes.
Collateral history
In case the patient is confused or unconscious, then inquire the family, caregiver or bystanders regarding the last meal, medications or symptoms the patient experienced.
Prehospital Treatment Of Hypoglycaemia
The approach to assessing and treating prehospital hypoglycaemia is largely the same in both adults and children, regardless of whether or not they have diabetes. In patients without diabetes, hypoglycaemia is usually considered when blood glucose falls between 4.0 mmol/L, provided that symptoms are present.
Assessment should always begin with a structured <C>ABCDE evaluation, addressing any immediate life-threatening issues. Medical alert jewellery, cards, or other sources of patient information should be sought where available. A capillary blood glucose reading must be taken and documented before treatment is started.
Patients who are unconscious (GCS ≤8), convulsing, or severely agitated should be managed as a medical emergency. After stabilising airway, breathing, and circulation, intravenous glucose 10% should be given promptly.
If this is not possible, a single intramuscular dose of glucagon may be administered, although this is less reliable in certain groups. Glucagon relies on adequate glycogen stores and can be ineffective in patients who drink excessive alcohol, are malnourished, follow a low-carbohydrate diet, or use sulphonyl urea medications. For these reasons, intravenous glucose is the preferred option whenever possible. Patients should be kept nil by mouth due to the risk of aspiration.
Blood glucose should be checked again after five minutes, and additional doses of IV glucose titrated if levels remain below 4.0 mmol/L.
If there is still no improvement, a repeat assessment should be made at 15 minutes, and urgent transfer to hospital considered.
Vital signs and neurological status should be monitored continuously during transport, and a pre-alert call made if required.
Patients who are awake, orientated, and safe to swallow can usually be managed orally. Rapid-acting carbohydrate should be provided in the form of glucose tablets, glucose drinks, fruit juice, glucose gel, or sugar dissolved in water.
Chocolate and other fatty foods should not be used because they are absorbed too slowly.
If the patient is unable to take food or drink safely, glucose gel can be rubbed into the buccal mucosa, or IV glucose 10% or intramuscular glucagon can be given if IV access is not available.
Blood glucose should be re-checked after 10–15 minutes. If it remains low, oral carbohydrate can be repeated up to three times. Persistent hypoglycaemia despite this requires escalation to intravenous therapy.
Once glucose levels rise above 4.0 mmol/L, patients should be encouraged to eat a longer-acting carbohydrate source such as bread, biscuits, or milk, or to consume a full meal if one is due. Those treated with glucagon should take a larger portion of starchy carbohydrate to replenish glycogen stores. Patients who use insulin pumps may not need this additional intake, depending on their individual management plan.
Not all patients need to be transported to hospital. Those who have experienced a mild or moderate episode, have made a full recovery, have maintained a glucose level above 4.0 mmol/L, and have eaten a suitable carbohydrate snack can often remain at home, provided they are left in the care of a responsible adult in the case of children. However, patients should be advised to call for further help if symptoms return.
Ambulance services should ensure that a notification is passed to the patient’s GP or diabetes care team in line with local pathways. Anyone who required third-party assistance during the hypoglycaemic episode should be referred to a specialist diabetes service. Patients who use insulin but are not currently supported with continuous or flash glucose monitoring should be encouraged to discuss these technologies with their diabetes team, as they reduce the risk of recurrent severe hypoglycaemia. Referral does not require patient consent, but patients should be informed that it is being made.
Written patient information should be provided where available, and advice given on issues such as driving safety following a hypoglycaemic episode.
Certain groups are more likely to need ongoing management in hospital. These include older or frail patients, those with a low BMI, individuals living alone, or patients on multiple medications. Hospital transfer should also be considered for patients who have experienced repeated episodes in the past 48 hours, those who had a severe event with a slow or incomplete recovery, and those prescribed sulphonylureas, as these drugs can lead to prolonged or recurrent hypoglycaemia.
Other factors warranting hospital care include: a first hypoglycaemic episode in someone without known diabetes, persistent glucose levels below 4.0 mmol/L despite treatment, failure to regain full mental status within 10 minutes of intervention, or the presence of additional complicating conditions such as infections, seizures, cardiovascular symptoms, alcohol intoxication, or concurrent serious illness.
Red Flags Of Prehospital Hypoglycaemia
- Altered states of the mind or loss of consciousness
- Seizures
- Initial glucose therapy was ineffective.
- Recurrent or repeated episode
- Signs of serious illness, such as sepsis liver failure or kidney disease
- Lack of symptoms of hypoglycaemia (unawareness)
Key Points
- Prehospital Hypoglycaemia is a condition which occurs when blood glucose is below 4.0 mmol/l in a diabetic and 3.0 mmol/l in a non- diabetic, and commonly occurs in insulin therapy, skipping meals, the use of alcohol, or illness.
- Common signs include shaking, sweating, slurred speech confusion, fits, and unconsciousness.
- Always check and record blood glucose accurately before treatment,
- Consult hospital in case of severe symptoms, repetitiveness or unresponsiveness
References
National Institute of Diabetes and Digestive and Kidney Diseases. (2025, February). Low blood glucose (hypoglycemia). U.S. Department of Health & Human Services. Retrieved July 8, 2025, from https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/low-blood-glucose-hypoglycemia
Joint Royal Colleges Ambulance Liaison Committee (JRCALC). (n.d.). JRCALC Plus: Hypoglycaemia guidelines. Retrieved from http://www.diabetologists-abcd.org.uk/JBDS/JBDS_HypoGuideline_FINAL_280218.pdf
Mathew, P., & Thoppil, D. (2025). Hypoglycemia. In StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved July 8, 2025, from https://www.ncbi.nlm.nih.gov/books/NBK5348421
Zaccardi, F., Davies, M. J., Dhalwani, N. N., Webb, D. R., Housley, G., Shaw, D., Hatton, J. W., & Khunti, K. (2016). Trends in hospital admissions for hypoglycaemia in England: A retro-spective, observational study. The Lancet Diabetes & Endocrinology, 4(8), 677–685. https://doi.org/10.1016/S2213-8587(16)30091-2
