dm_hhs
Table of Contents
hyperosmolar hyperglycaemic state (HSS or HONK)
see also:
- Western Health procedures (intranet only):
introduction
- formerly known as hyperosmolar non-ketotic coma (HONK)
- type 2 diabetic patients who become unstable for a period of days can develop a severely dehdrated hyperosmolar state due to osmotic diuresis resulting from persistent severe hyperglycaemia
- these patients are critically ill with high morbidity and mortality and require urgent resuscitation and investigation of precipitating cause
- early ICU and endocrine unit liason is advisable
- presence of ketonuria and acidosis should be managed as per diabetic ketoacidosis (DKA) instead of this guideline which has been adapted from the Western Health guideline in 2013.
diagnostic criteria
- blood glucose Level (BGL) > 33 mmol/L
- pH > 7.30
- serum bicarbonate > 15 mmol/L
- urine ketones: absent or small
- serum osmolality >320 mOsm/kg
- Note - osmolality approximation: [(Na + K) x 2] + urea + glucose
- neurological abnormalities frequently present
Mx of HHS
initial Mx in ED
- iv access
- start iv fluid Rx to rehydrate (see below)
- bloods for FBE, U&E, glucose, LFTs, lipase, troponin, VBG, blood cultures
- ECG
- CXR
- urinalysis, MSU m/c/s
- consider need for central line if co-morbid conditions such as congestive cardiac failure
look for precipitating cause
- infection
- acute major illnesses such as myocardial infarction, cerebrovascular accident or pancreatitis
- drugs that affect carbohydrate metabolism including glucocorticoids, second-generation antipsychotic agents
- poor compliance with insulin or oral hypoglycaemic regimen
- newly recognised Type 2 Diabetes Mellitus
rehydration
- patients often have severe intravascular depletion due to prolonged periods of hyperglycaemia resulting in fluid loss from osmotic diuresis.
- usual fluid deficit is around 4-5 litres.
- a typical rate of replacement (tempered by co-morbidities such as history of congestive cardiac failure, ischaemic heart disease (IHD)):
- Normal Saline 1L – 2L stat, followed by
- 1L over 2 hours (hrs), then
- 1L over 4 hrs
- once the blood glucose ≤ 20mmol/L, (aim is to achieve this gradually over the 1st 24 hrs), commence 8 hourly 1L 5% Dextrose in addition to Normal Saline until re-hydration is complete.
insulin infusion
- use pump set up with Actrapid 100 units in 100mls Normal Saline = 1 unit/millilitre (ml)
- discard first 10-20mls before connecting to patient to saturate insulin binding sites on plastic tubing
- initial insulin infusion rate is 0.02 units/kg/hr
- target BGL range: 15-20mmol/L within first 24 hrs
- check BGL hourly
- if BGL < 15mmol/L, cease insulin infusion and contact endocrine unit
- if BGL ≥ 15mmol/L and falling by ≥4mmol/hr, reduce insulin infusion rate by 1 unit/hr
- if BGL ≥ 15mmol/L and not falling by ≥2mmol/hr, increase insulin infusion rate by 1 unit/hr
- if intravenous access is temporarily not possible, subcutaneous quick acting insulin can be given (low doses eg 4-6 units, and observe response over next 2 to 4 hours)
- when the patient is recovering and eating normally, they should be stepped down to a basal bolus or premixed insulin regimen. Ultimately many patients will return to their usual medications if appropriate or initiated on oral hypoglycemic agents if newly diagnosed Type 2 Diabetes.
- do not try to normalise blood glucose quickly as this can lead to cerebral disequilibrium and worsening of confusion
monitor and Rx serum potassium levels
- these patients are at high risk of developing hypokalaemia during Rx
- while on an insulin infusion, K+ levels should be checked every 2 hours for the first 6hrs. After 6 hrs, K+ level should be checked every 4-6hrs.
- KCl infusion rates:
- K+ < 3.5 mmol/L: 20mmol/hr
- K+ 3.6-4.5 mmol/L: 10mmol/hr
- K+ 4.5-5.5 mmol/L: 5mmol/hr
- K+ > 5.5mmol/L: nil
DVT prophylaxis
- these patients have a high risk of developing DVT so should be given prophylactic dose enoxaparin
serum sodium and choice of ongoing iv fluids
- hyperglycaemia causes a reduction in serum sodium levels
- predicted sodium levels once glucose level normalises can be determined via:
- Predicted Na+ concentration = Measured Na+ concentration + 1/3 BGL
- the initial hydration fluids should almost always be Normal saline, but ½ Normal Saline may be needed if the predicted Na+ (after correction, using this formula) continues to be >145 mmol/L after significant fluid hydration (e.g. 3 litres 0.9% Normal Saline)
dm_hhs.txt · Last modified: 2015/05/15 15:31 by 127.0.0.1