Question

1. Case Study History: A 35 year old woman with Type 1 diabetes is brought to the emergency department by ambulance after being found in her house severely unwell. Following a discussion with her partner, it emerges she has not been eating for the past few days due to illness and vomiting. As a precaution she has been omitting her insulin. Examination: On examination, she appears drowsy. Her breath smells of acetone and her respirations are deep and fast. She is started on oxygen by mask. pH 7.18 pC02 21 mm Hg pO2 187 mm Hg HCO3 6 mmol/L SO2 99.8% Glucose 35.0 mmol/L 1. Describe her acid base status. 2. What is the most likely diagnosis? 3. Is the patient likely to correct the acid base imbalance without medical intervention? Why? 4. What is causing the patient to breathe in the manner described?

Answer 1

1. Arterial Blood Gas ( ABG) is done on the 35 year old women as she was taking short and fast breath. The ABG levels indicate -

pH - 7. 18 - The normal level of pH in blood is 7.35 to 7.45 indicating decreased pH showing acidic nature.

pCO2 - 21 mm Hg - The normal level of pCO2 is 35 to45 mm Hg indicating decreased levels of pCO2 showing respiratory alkalosis.

HCO3 - 6 m mol/L - The normal levels of bicarbonate is 22 to 30 mEq/L indicating severe low levels of bicarbonate.

The acidic pH, low pCO2 levels, increased pO2 levels and low bicarbonate levels in the arterial blood examination reveals the woman has metabolic acid base imbalance which is termed as Metabolic Acidosis.

2. The likely diagnosis is Diabetic ketoacidosis.

Diabetic ketoacidosis is a serious complication that occurs in diabetics when the body produces ketones due to lack of insulin. When there is lack of insulin and if the person is starving, the body starts breaking up fat for fuel . This process results in acetone build up leading to Diabetic ketoacidosis which can turn fatal if left untreated.

3. The patient needs medical intervention to correct the condition.

Patient is given lot of fluids either orally or intravenously . Fluids help in diluting the excess sugar levels in the blood as well as rehydrate the fluids which were lost with excess urination.

Electrolytes too have to replaced intravenously as lack of insulin lowers the electrolyte levels such as sodium,potassium,chloride which are very necessary for normal functioning of heart, kidneys and other organs.

Insulin therapy is given to reverse the diabetic ketoacidosis condition . Initially insulin is given via vein and once the blood sugar and the pH normalises , it is stopped and switched over to subcutaneous route.

4. The patient has metabolic acidosis ,which means there is increased amount of acid in blood . The body tries to compensate by deep ,rapid breaths inorder to expel more acid from lungs. ( expelling out more carbondioxide) This pattern of breathing is called Kussmaul breathing taking its name from the person who explained this breathing pattern.