Answer to Question 1

Resp: 3

SpO2: 1

Air/O2: 2

BP: 0

Pulse: 2

Consciousness: 0

(initially)Temperature: 0

Total: NEWS 8

A NEWS score of 8 indicates a ‘high’ level of risk and warrants anurgent/emergency assessment by senior clinicians. This patient is very unwell and ITU should also be informed.These patients are often automatically triaged by critical care outreach teams once their NEWS reaches 7.

Answer to Question 2

The most striking abnormality is in her renal function. This is most likely an AKI as even though we do not have previous renal function results to compare with, the normal calcium and phosphate point to an acute deterioration in renal function (in CKD hypocalaemia often leads to an increase in PTH–secondary hyperparathyroidism which subsequently sequesters phosphate in the blood). Similarly, the lack of a normocytic anaemia secondary to a chronic reduction in the ability of the kidneys to produce EPO points to an acute kidney pathology.

Her Urea: Creatinine ratio is < 100 and as such implies an intrinsic renal cause of her deterioration, as opposed to a pre–renal cause e.g. dehydration/shock or renal artery stenosis. The most likely culprit here is an inappropriately high gentamicin dose by her GP, as the drug is dosed by a patient’s ideal body weight NOT their actual body weight due to gentamicin’s poor lipid solubility. Gentamicin is renally excreted and at toxic doses can lead to acute tubular necrosis and subsequent AKI.

The uraemia is driving her metabolic acidosis, with partial respiratory compensation (hyperventilation).

Her electrolyte disturbance is a common picture in AKIs, with sodium being haemodiluted due to the extra fluid retained and potassium being withheld within the bloodstream due to the acidosis.

Answer to Question 3

This is in essence ventricular tachycardia with features of:

–Broad QRS > 120ms

–Tachycardia

However, the distinguishing feature of thetall, tented T–waves points to the underlying cause of this arrythmia–severe hyperkalaemia. This is likely secondary to her AKI combined with her ACE inhibitor, which further increases blood potassium levels.

Answer to Question 4

An A–E approach should be adopted, and she will likely require intubation and ventilation. Hyperkalaemia is usually managed as follows:

–Calcium chloride (10ml of 10%)–This stabilizes the cardiac membrane and prevents further arrythmias

–Insulin/dextrose infusion (50 units actrapid in 50 mls 20% dextrose)–this drives the potassium into cells, reducing the serum K+ concentration

–In more severe cases, calcium chelators e.g. calcium resonium and haemofiltration can also be used

Sources

Image 1: https://liftl.com/wp-content/uploads/2018/08/ECG-Hyperkalemia-serum-potassium-9.3.jpg