Hypocalcaemia Flashcards
What is the normal serum calcium concentration?
2.2mmol/L - 2.6mmol/L
What is hypocalcaemia?
It is defined as a serum calcium concentration less than 2.2mmol/L
What are the two classifications of hypocalcaemia?
Mild Hypocalcaemia
Severe Hypocalcaemia
What is mild hypocalcaemia?
It is defined as a serum calcium level > 1.9mmol/L, in which individuals are asymptomatic
What is severe hypocalcaemia?
It is defined as a serum calcium level < 1.9mmol/L, in which patients are symptomatic
What are the eight risk factors associated with hypocalcaemia?
Hypoparathyroidism
Pseudohypoparathyroidism
Parathyroid Surgery
Acute Pancreatitis
Chronic Kidney Disease
Rhabdomyolysis
Vitamin D Deficiency
Magnesium Deficiency
What are the seven clincial features associated with hypocalcaemia?
Muscle Spasms
Muscle Cramping
Perioral Paraesthesia
Chvostek’s Sign
Trousseau’s Sign
Seizures
Hypertension
How do we test for Chvostek’s sign?
It involves tapping the patient’s parotid, over the facial nerve
What is a positive Chvostek’s sign?
It is indicated by facial muscle twitching
How do we test for Trousseau’s sign?
It involves applying a blood pressure cuff on the patient’s arm and inflating it above their systolic level
What is a positive Trousseau’s sign?
It is indicated by carpal spasm, in which there is wrist and finger flexion
What are the three investigations used to diagnose hypocalcaemia?
Blood Tests
Arterial Blood Gas (ABG)
ECG Scan
What are the six blood test results of hypocalcaemia?
Decreased Calcium Levels
Normal/Decreased PTH Levels
Normal/Increased Phosphate Levels
Normal ALP Levels
Decreased Magnesium Levels
Decreased Vitamin D Levels
What is the first line investigation used to determine the cause of hypocalcaemia?
Parathyroid hormone blood test
What ABG feature indicates hypocalcaemia?
Respiratory alkalosis - in the presence of normal phosphate levels
What ECG feature indicates hypocalcaemia?
Prolonged QT interval > 460ms
What is the normal QTc interval?
350ms - 460ms
What is the conservative management option of hypocalcaemia?
It involves detection and treatment of the underlying cause of hypocalcaemia
What is the pharmacological management option of hypocalcaemia?
IV Calcium Gluconate
When is IV calcium gluconate used to manage hypocalcaemia?
It is the first line management option used to manage severe hypocalcaemia
What dose of IV calcium gluconate is administered to manage hypocalcaemia?
10ml of 10% solution for a period of 10 minutes
The initial bolus can be repeated until the patient is asymptomatic and/or calcium levels have significantly increased
What monitoring should be conducted during IV calcium gluconate administration?
ECG scan
