Lab case 393 interepretation

Posted on by

PH = 7.28, that is moderate acidaemia.

PCO2 = 73 mmHg. This means we have respiratory acidosis.

Next, we need to calculate the compensation. It is not clear from the history provided that this case is acute or chronic respiratory acidosis. We are going to consider both possibilities.

For acute respiratory acidosis we expect HCO3 to increase by 1 for every 10 pCO2 higher than 40. According to that, if the case was purely acute respiratory acidosis, then expected HCO3 should be: 24 + (33 x 0.1) = 27.3. This patient HCO3 is higher than that (34 mmHg)

For chronic respiratory acidosis, we expect HCO3 to increase by 4 for every 10 pCO2 higher than 40. According to that, if the case was purely chronic respiratory acidosis, then expected HCO3 should be 24 + (33 x 0.4) = 37.7. This patient HCO3 is less than that (34 mmHg).

This means that the case was either acute on chronic or there is additional metabolic process.

Next, we will calculate the anion gap. Anio gap = Na – (Cl + HCO3).

That is = 102 – (26 + 34) = 42, So we have HAGMA.

We can’t calculate the delta ratio for this patient due to the presence of high HCO3 level.

Other abnormal findings:

Na = 102 mmol/L, this is severe, life threatening hyponatraemia.

K = 2.4 mmol/L, this is severe hypokalaemia.

Cl = 26 mmol/L, this is hypochloraemia.

Ionised Ca = 0.81, that is hypocalcemia (Normal level 1.15 – 1.25 mmol/L), this is moderate to severe hypocalcemia.

Glucose = 13.8 mmol/L, this is hyperglycemia

Lactate = 27 mmol/L, this is extremely high lactate level (Hyperlactataemia).

Creatinine = 562 umol/L, this number will put the patient at end stage renal failure range, even if the patient is very young.

*** This patient was vomiting for few days then developed seizure secondary to severe hyponatraemia. Seizure explains the extremely high lactate level.

Vomiting usually cause hypochloremia and alkalosis due to loss of HCL.

In this case all the electrolytes’ levels were low, possibly diluted with water.

Unfortunately, we don’t have enough information about this case. However, with these blood gases the patient will need ICU admission and most likely dialysis.