Fig. 1

A Primary disturbance is a metabolic acidosis and the deviation from baseline is − 17 mmol/L. The compensation is full with a hyperventilation resulting in a pCO₂ of 19 mmHg. The script uses Boston formulas. The graphic output shows the low bicarbonate and the low pCO₂ levels, as well as the pH which has been compensated close to normal. B Primary disturbance is a metabolic acidosis and the deviation from baseline is − 19 mmol/L, which equals a critical metabolic acidosis. However, in this case, there is a secondary respiratory acidosis disturbance making it impossible for the patient to hyperventilate the pCO₂ down to 16 mmHg, which would be a complete compensation. Instead, the pCO₂ has remained at 30 mmHg level. This means that the compensation is 10 mmHg (equals actual compensation = [40–30] mmHg against full compensation = [40–16] mmHg and thus 42 percent). C Primary disturbance is a chronic respiratory alkalosis and the deviation from baseline is − 11 mmHg. Because the compensation overshoots the level of full compensation for acute respiratory alkalosis, which would equal a bicarbonate level of 22 mmol/L (instead it is 19 mmol/L) the disturbance is chronic. In fact this equals full compensation for chronic disturbance and the script thus returns that the primary respiratory alkalosis disturbance is chronic, fully compensated and that no secondary disturbance is identified. Also, the pH is within normal range. D Primary disturbance is a metabolic acidosis with a deviation from the baseline of − 18 mmol/L, with an elevated anion gap of 19. The script returns a secondary disturbance of a respiratory acidosis, because the compensation is not full; there is a 8 mmHg difference (actual pCO₂ value is 25 mmHg) to full which would be 17 mmHg. In this case the delta ratio is calculated to 0.39, which indicates a tertiary disturbance. The [Na⁺–Cl⁻] difference is 18 mmol/L and the script returns a suggestion of a tertiary disturbance as a hyperchloremic acidosis