Page 85 - WSAVA2017
P. 85

Table 2. Treatment options for hyperkalaemia
An Urban Experience
 Treatment of hyperkalaemia
   Intravenous fluids (Hartmann’s)
 Bolus 5 – 20 mL/kg if in shock; otherwise as infusion
 10% calcium gluconate
  0.5 – 1.5 mL/kg IV over 10 minutes monitoring ECG
 Regular insulin (Actrapid®)
  0.2 – 0.5 U/kg IV (always follow with glucose)
 50% glucose
  0.5 – 1.5 mL/kg diluted 1:1 with Hartmann’s or water for injection
 Sodium bicarbonate
  0.5 – 1.5 mL/kg diluted 1:1 with Hartmann’s or water for injection
  0.01 mL/kg IV over 5 minutes
 Treat underlying cause
   Discontinue any drugs; divert urine;
 When considering the treatment options, consider the severity of hyperkalaemia and its clinical signs, how quickly you want to resolve it, and what the underlying condition is. If the hyperkalaemia is life threatening, the first step is to administer calcium gluconate, as it will stabilise the resting membrane potential within 5 – 15 minutes. It does not treat the hyperkalaemia itself, but instead treats the life-threatening arrhythmia.
If the patient is in shock, the next step would be to
treat the shock with a fluid bolus. When considering
the type of fluids, Hartmann’s is recommended over 0.9% NaCl, as 0.9% NaCl has a higher concentration of chloride contributing to acidosis. Hartmann’s has a lower concentration of chloride; and in addition, lactate, which acts as a buffer which will help reverse any acidosis if present.
Insulin and glucose will cause intracellular movement
of potassium lowering the serum concentration. If the patient is only mildly hyperkalaemic or not showing clinical signs of hyperkalaemia, the author gives glucose without insulin, as insulin administration will cause hypoglycaemia. The glucose must be diluted 1:1 with Hartmann’s or water for injection as the hyperosmolality can cause phlebitis. However, in more life-threatening hyperkalaemia, regular insulin (Actrapid®) is indicated with concurrent glucose bolus followed by 2.5 – 5% glucose in the intravenous fluids, with blood glucose monitoring. The type of insulin must be a short acting insulin, which the most commonly available brand is Actrapid®.
Sodium bicarbonate is reserved for refractory hyperkalaemia (unresponsive to the above treatment); or in severe metabolic acidosis (pH < 7.0). The bicarbonate will cause intracellular movement of potassium lowering the serum concentration. The reason bicarbonate is resolved for severe cases is as sodium bicarbonate can have side effects.
Another option for refractory hyperkalaemia is intravenous terbutaline, which causes intracellular translocation of potassium via the Na+/K+-ATPase pump.
Once the patient is cardiovascularly stable, address the underlying cause. If there is a urethral obstruction, pass a urinary catheter; if there is uroperitoneum, place a urinary catheter and abdominal drain (the author preference is
a Mila chest drain placed in the abdomen). Discontinue any drugs which will cause iatrogenic hyperkalaemia (e.g. spironolactone, IV potassium supplements). If the hyperkalaemia is due to acute kidney injury, consider
a diuretic such a furosemide. If the hyperkalaemia is associated with acidaemia, treat the underlying acidosis.
If life threatening hyperkalaemia persists despite the above therapeutics, peritoneal dialysis or haemodialysis is recommended.

   83   84   85   86   87