Lab case 401 interpretation


Question 1:

pH 7.62 that is moderate to severe alkalaemia

HCO3 36mmol/L, so we have metabolic alkalosis.

Next, we need to calculate the compensation, that is calculated as:

Expected PCO2 = 0.7 X HCO3 +20 (+/-5). This will be: 45 (40 – 50). So, we have additional respiratory alkalosis as this patient pCO2 is lower than the expected (33).

Next, we will calculate the Anion Gap. This is calculated as Na – (Cl + HCO3) = 23, So we have additional HAGMA.

We have triple metabolic processes here. This patient had combined metabolic and respiratory alkalosis with HAGMA.

Other abnormal findings:

Na = 127 mmol/L, that is moderate hyponatraemia.

K = 2.3 mmol/L, that is severe hypokalaemia.

Cl = 68 mmol/L that is hypochloraemai.

We have dilution of all the electrolytes. That usually occurs when there is excess water in the body. This could also be applied to the low Hb level for this patient.

Lactate = 8 mmol/L. This is severe hyperlactataemia.

Creatinine = 172 umol/L. This is high and reflects renal failure.

This patient had ascites secondary due to low albumin level that is caused by liver failure. Although this patient is fluid overloaded, he is intravascularly dehydrated. This intravascular dehydration is the cause of his metabolic alkalosis (Contraction Alkalosis).

The fluid (Water) overload is the cause of electrolytes dilution, hence hypokalaemia and hyponatraemia.

The respiratory alkalosis is caused by the patient ascites. The excessive volume of fluids in the abdomen will reduce the tidal volume then the patient compensates by increasing his respiratory rate and this will lead to respiratory alkalosis.

Metabolic acidosis (HAGMA) is due to high lactate level (Possibly urea level as well). High lactate is caused by liver failure. Liver failure affect the metabolism of lactate and leads to hyperlactataemia.

 Question 2:

Stages of alcohol withdrawals

  1. Minor withdrawal, this starts 6 to 24 hours after last alcoholic drink. It presents as tremor, anxiety, nausea and vomiting and insomnia.
  2. Major withdrawal, this starts 10 to 72 hours after last alcoholic drink. It presents as Hallucinations (Visual or auditory), sweating, tachycardia and increase in blood pressure.
  3. Seizures, that usually happens 2 days after last alcoholic drink.
  4. Delirium Tremen, that usually happens 2,3 to 10 days after last alcoholic drink. It presents with confusion and disorientation with high temperature (Fever).