Electrolytes

Question 1

Describe the normal range for sodium levels in the body.

Answer 1

135-145.

Question 2

What is the main organ affected by changes in sodium levels?

Answer 2

CNS.

Question 3

What are the main CNS manifestations of abnormal sodium levels?

Answer 3

Confusion, convulsion, coma.

Question 4

What is the most common cause of hypernatremia?

Answer 4

Diabetes Insipidus.

Question 5

What is the most common cause of hyponatremia?

Answer 5

SIADH.

Question 6

What is the recommended fluid for treating hyponatremia?

Answer 6

Normal saline (0.9%).

Question 7

What should be used for hyponatremia with confusion or seizure?

Answer 7

Hypertonic saline (3%).

Question 8

What is the treatment for hyponatremia with severe neurological manifestations?

Answer 8

Hypertonic saline (3%).

Question 9

What neurological condition can result from rapid correction of hyponatremia?

Answer 9

Central pontine myelinolysis leading to quadriplegia.

Question 10

Describe the normal range for potassium levels in the body.

Answer 10

3.5-5.

Question 11

What EKG changes are seen in hyperkalemia?

Answer 11

Hyper-acute T-wave (tall T-wave), wide QRS, prolonged PR.

Question 12

What is the first-line treatment for hyperkalemia with EKG changes?

Answer 12

Calcium gluconate.

Question 13

What should be administered first for hyperkalemia with severe chest pain, dyspnea, or palpitations?

Answer 13

Calcium gluconate.

Question 14

What is the initial treatment for hyperkalemia with potassium levels above 7?

Answer 14

Calcium gluconate.

Question 15

What is the treatment for hyperkalemia below 7 without EKG changes or manifestations?

Answer 15

Insulin and glucose.

Question 16

How can potassium levels be rapidly decreased?

Answer 16

With insulin and glucose.

Question 17

What is the only drug that removes potassium from the body?

Answer 17

Kayexalate (resonium).

Question 18

What is the recommended treatment for hyperkalemia in end-stage renal disease patients?

Answer 18

Dialysis.

Question 19

What action should be taken if potassium levels are less than 6?

Answer 19

Stop the offending drug only.

Question 20

Describe the treatment for emergency hypercalcemia.

Answer 20

IV fluids and diuretics.

Question 21

What is the first presentation of hypocalcemia?

Answer 21

Peri-oral numbness.

Question 22

What is the cause of hypocalcemia following total thyroidectomy?

Answer 22

Hypoparathyroidism due to removal of all 4 parathyroid glands.

Question 23

If a patient develops perioral numbness after surgery but total calcium levels are normal, what could be the cause?

Answer 23

Hypocalcemia.

Question 24

Describe the treatment for hypocalcemia requiring rapid correction before surgery.

Answer 24

IV calcium is administered.

Question 25

What is the long-term treatment for hypocalcemia?

Answer 25

Calcium plus vitamin D.

Question 26

What is the initial step in managing tetany caused by hyperventilation?

Answer 26

Breathing into a bag.

Question 27

How is hypocalcemia tetany managed if it persists after breathing into a bag?

Answer 27

With calcium gluconate.

Question 28

Define the cause of decreased total calcium but not ionized calcium due to hypoalbuminemia.

Answer 28

No tetany. Hypocalcemia: Practice Essentials, Pathophysiology ... Medscape https://emedicine.medscape.com › Nephrology 10 Nov 2022 — Patients with a decrease in total serum calcium may not have "true" hypocalcemia, which is defined as a decrease in ionized calcium. A reduction ...

Question 29

What is the diagnosis for a post-operative patient on TPN who develops a skin problem?

Answer 29

Zinc deficiency.

Question 30

What is the most common cause of zinc deficiency?

Answer 30

TPN.

Question 31

Describe the diagnosis for a patient with hyponatremia, increased urine Na, and osmolarity.

Answer 31

SIADH.

Question 32

What is the most common drug causing SIADH?

Answer 32

Carbamazepine.

Question 33

What is the most common cancer causing SIADH?

Answer 33

Small cell lung cancer.

Question 34

How can any neurological insult lead to SIADH?

Answer 34

By causing a disruption in the body's fluid balance.

Question 35

In SIADH, how do the serum osmolarity, urine osmolality, and urine sodium concentration change?

Answer 35

Serum osmolarity decreases, urine osmolality increases, urine sodium concentration increases.

Question 36

In Diabetes insipidus, how do the serum osmolarity, urine osmolarity, and urine sodium concentration change?

Answer 36

Serum osmolarity increases, urine osmolarity decreases, urine sodium concentration decreases.

Question 37

What are the treatment options for hyponatremia in SIADH based on severity?

Answer 37

Mild: fluid restriction, Moderate: normal saline plus diuretics, Severe or with CNS manifestations: hypertonic saline (3%).

Question 38

What is the initial step in managing a child with meningitis who develops a seizure and hyponatremia?

Answer 38

Administer hypertonic saline (3%).

Question 39

What is the diagnosis for a patient with hypernatremia, decreased urine Na, and osmolarity?

Answer 39

DI (Diabetes insipidus).

Question 40

What is the most common drug causing Diabetes insipidus?

Answer 40

Lithium.

Question 41

What is the diagnosis for a patient with hyponatremia, decreased urine Na, and osmolarity?

Answer 41

Psychogenic polydipsia.m Psychogenic polydipsia, also known as primary polydipsia, involves excessive water intake driven by psychological factors. Key factors to know include: 1. **Symptoms**: Excessive thirst and fluid intake, leading to polyuria (excessive urination). 2. **Risks**: Can cause water intoxication, hyponatremia (low sodium levels), and associated symptoms like confusion, seizures, or coma. 3. **Diagnosis**: Differentiation from diabetes insipidus and other causes of polyuria; involves water deprivation tests and psychiatric evaluation. 4. **Management**: Fluid restriction, addressing underlying psychiatric conditions, and monitoring electrolytes. For more details, refer to the RACGP guidelines.

Question 42

Describe how to differentiate between diabetes insipidus (DI) and psychogenic polydipsia using the H2O deprivation test.

Answer 42

Normalization of lab values after the test indicates psychogenic polydipsia, while no normalization and low urine osmolality indicate DI.

Question 43

Do you determine the diagnosis of syndrome of inappropriate antidiuretic hormone secretion (SIADH) in a patient with hyponatremia, increased urine sodium, and osmolarity?

Answer 43

Yes, those criteria suggest SIADH.

Question 44

Define the diagnosis of diabetes insipidus (DI) in a patient with hypernatremia, decreased urine sodium, and osmolarity.

Answer 44

DI is the likely diagnosis.

Question 45

How do you assess acid-base balance in a patient?

Answer 45

The first step is to assess pH levels, followed by evaluating CO2 and HCO3 levels for respiratory or metabolic changes.

Question 46

When does a patient require IV calcium administration?

Answer 46

IV calcium is needed when the patient is symptomatic, has serum calcium below 1.9 mmol/L, or rapid correction is necessary before an operation.

Question 47

What is the normal range for urine osmolarity?

Answer 47

The normal range for urine osmolarity is 500-800 mOsm/kg.