Metabolic acidosis case discussion

Case discussion on the metabolic acidosis enables the proper understanding of the pathophysiology, mechanisms, precipitating factors, complications and treatment of metabolic acidosis.

Case 01

A 25 year old woman with diabetes mellitus type 1 presented in coma state. On admission following biochemical tests were done

Serum electrolytes

electrolytes	Test value	Reference
Sodium (Na+)	135mmol/l	132-144
Potassium (K+)	5.7mmol/l	3.2-4.8
Chloride (Cl-)	101mmol/l	98-108
Bicarbonate (HCO3-)	10mmol/l	23-33
urea	9mmol/l	3-8
RBS	30.5mmol/l	3-5.5
Urinary ketone bodies	Positive

Blood gas analysis

pH	7.09	7.35-7.45
H+	80nmol/l	35-45
Pco2	20mmhg	35-45

1. Identify the biochemical derangements of this patient.
2. explain the pathophysiology of these abnormalities
3. Serum electrolyte levels were done 6 hours after commencement of insulin and normal saline therapy and it revealed following results.

Sodium (Na+)	143mmol/l	132-144
Potassium (K+)	2.8mmol/l	3.2-4.8

i.What is the probable cause for this change?

ii.What precautions should you take to avoid this situation?

Answer case 01

1. biochemical derangements

hyperkalemia

acidosis (reduced pH, reduced Pco2, reduced HCO3-)

uremia

severe hyperglycemia

2. explanation

Severe insulin deficiency occurs in type I diabetes mellitus leads to increased lypolysis as the body cannot utilize the glucose in the absence of insulin. Lypolysis results more free fatty acids which are used to produce energy. This process will result ketone bodies such as acetone, acetoacetone and hydroxybutyrate. Because of the deficiency of insulin, hyperglycemia will result. Due to the accumulation of ketone bodies, acidity of the blood goes up. Bicarbonate is a buffer and it will come into the action therefore bicarbonate level goes down due to the consumption. Excess ketone bodies will appear in urine.

3. i. with insulin therapy glucose starts entering to the cells. This is accompanied with potassium as well. Therefore potassium level goes down.

ii. to avoid this KCl has to be infused with IV fluids with frequent monitoring of the serum electrolytes.