Case 8

78 year old female

Brought in by SCDF ambulance. Acutely unwell.
BP 85/50, Temp 37.8. Drowsy and unresponsive.
No family members around to give more history.

What is the diagnosis?
Which drug would you give first in her management?

Answer : Hyperkalemia

On first look, the ECG looks bizarre and not like something which we can fit a pattern to. This in itself should already remind you to think of hyperkalemia. On closer inspection we can see that the QRS complexes are widened and there is also suggestion of tall T waves.

Management

• Immediate management in P1 area. Full monitoring.
• Supplemental oxygen
• IV access; take blood form FBC/ UE/ ABG/ cardiac enzymes & Troponin/ blood cultures; consider IV fluids but need to exclude fluid overload first
• Drugs

1. IV Calcium gluconate/ chloride (10 mls stat) - first drug to be given in treatment of hyperkalemia; to stabilise the myocardium
2. IV Insulin 10 units with IV Dextrose 50% 40 mls - shifts ECF potassium into ICF
3. IV Sodium Bicarbonate (1 meq/kg BW ) IV bolus over 5 mins - also to shift ECF potassium into ICF. Limited use if patient is non-acidotic, and carries risk of fluid overload/ cerebral oedema.

Other drugs which can be considered include Salbutamol nebulisation (be careful in patients with IHD because of resultant tachycardia), as well as Resornium (K-binding resin) but it's not much use in A&E because of relatively longer onset of action (about 1-2 hrs).

This lady has a history of chronic renal impairment on dialysis. Her acute presentation is probably exacerbated by a concomitant infection (chest/ urine).

Remember :

• Consider non-cardiac pathologies when intepreting ECG
• When confronted with bizarre-looking ECG, consider severe hyperkalemia

Case 4

19 year old female

C/o abdominal pain and vomiting for 3 days.
No past medical history of note

O/e BP 90/55, HR 120/min
Abdomen soft

Basic blood investigations as below:

FBC : TWC 16,000, Hb 12.1, Platelets 227

U/E : Na 131, K 3.1, Cl 97, Bicarb 12, Creatinine 108

What simple test would give you the diagnosis?
How would you manage this patient?


Answer : Capillary blood glucose

The most striking abnormality in the blood tests is the low bicarbonate level of 12 mmol/L (usual range 22-30). This implies a metabolic acidosis. Next, we can calculate the anion gap (Na + K - Cl - Bicarb) = 131 + 3.1 - 97 - 12 = 25.1. The normal range of the anion gap is usually quoted as 8- 16; hence what we have here is a high anion-gap metabolic acidosis (HAGMA).

Go back to medical school biochemical pathology, and you will (hopefully) remember the causes of HAGMA :

• Diabetic ketoacidosis (DKA)
  
• Severe uremia
• Drugs (salicylate, ethanol, methanol, ethylene glycol)
• Lacticacidosis

In this case, DKA is the most likely diagnosis (assuming no consumption of meds), and a hypocount will reveal a high capillary blood glucose reading. Of course you can do a serum ketone level or an arterial blood-gas (ABG) analysis which will be more definitive, but they take longer for the results to come back.

Approach

• Manage as P1 case - DKA patients may not look apparently ill but they can deteriorate precipitously. Immediate management is needed
• Immediate fluid resuscitation is critical - 1-3 L of normal saline within first hour.
• IV Insulin (usually 5-10 units bolus) followed by IV insulin infusion
• Close monitoring and replacement of electrolytes (esp. K) - remember that insulin shifts K into the cells (hence it is also treatment for hyperkalemia)
• Bicarbonate infusion - not critical as acidosis usually will correct with measures above. Carries risk of cerebral oedema
• Identify and treat underlying cause (e.g. antibiotics for sepsis)
• Admit to Endocrine/ Int Med. May need close monitoring in ICU/ High dependency unit

Remember :

• Patient usually does not have a history of diabetes. Their first presentation will be DKA.
• If not treated in time and aggressively enough, DKA carries a high mortality rate even in a young and apparently healthy individual.

• Not all abdominal pains are surgical in nature!