Hyperkalaemia & Hyporkalaemia

Lect..3,,,,4

Dr. Methaq A.M. Hussein
Assist.prof. of internal medicine
MRCP(UK)…. Endocrine, D.M (UK)

Causes of Hyperkalaemia

Decreased or impaired potassium excretion – renal failure, potassium-sparing diuretics, urinary obstruction, sickle cell disease, Addison disease, and systemic lupus erythematosus (SLE)

Additions of potassium into extracellular space - potassium supplements (eg, PO/IV potassium, salt substitutes), rhabdomyolysis, and hemolysis (eg, blood transfusions, burns, tumor lysis)

















Transmembrane shifts (ie, shifting potassium from the intracellular to extracellular space) - acidosis and medication effects (eg, acute digitalis toxicity, beta-blockers, succinylcholine)

Factitious or pseudohyperkalemia - improper blood collection (eg, ischemic blood draw from venipuncture technique), laboratory error, leukocytosis, and thrombocytosis

ECG Changes

From reduction of P wave amplitude and prolongation of PR interval to absence of P waves altogether.
Increase of QRS duration.
Increase of QT duration.
Slowing of heart rate.
T waves become tall and spiked.
Decreased R wave amplitude

3 Principles of Treatment

Stabilise myocardium
Move it into cells
Increase elimination

1.Calcium Gluconate…..to counteract the effect of K on the heart

Dextrose – Insulin 2.

Sodium Bicarbonate 3.
Calcium Resonium 4.
Salbutamol 5.
6.Furosemide
7.haemodialysis

HYPOKALEMIA

Causes of Hypokalemia
I. Decreased intake
A. Starvation
B. Clay Ingestion
II. Redistribution into Cells
A. Acid-Base (Metabolic Alkalosis)
B. Hormonal (Insulin, Beta agonist, Alpha )
C. Anabolic State (folic acid)
D. Other (Hypothermia, Pseudohypokalemia

III. Increased Loss

A. Nonrenal
1. Gastrointestinal Los
2. Integumentary Loss (sweat)
B. Renal

SIGNS & SYMPTOMS

Fatigue
Myalgia
Muscular weakness & paralysis
Hyporeflexia
Dyspnea
Arrhythmia
Predispose to digitalis toxicity
Constipation

ECG changes

Due to delayed ventricular repolarization
Early changes: flattening or inversion of T wave, prominent U wave, ST-segment depression, prolonged QU interval
Severe K+ depletion: prolonged PR interval, decreased voltage and widening of QRS complex

Periodic limb hypokalaemic paralysis

Patient coplain from recuurent attacks of palalysis……monitored as inpatient due to risk of resp. failure
Ppt. factors
1.heavy meals of CHO
2.straneuos excersize
3.standing from prolond sitting
4.awake from prolong sleeping





Causes
1.idiopathic channalopathy
2.thyroid disease
3.other causes of recurrent hupokalaemia

Treatment

1.monitor of repiratory sys……FVC
2.correction of hypokalaemia by oral KCL…if patient sever symptoms or cannot take orally ,,,so infusion wth fluid???????
Mannitol infusion with KCL
NO NO ….GW OR NORMAL SALINE ?????
3.treatment of the cause like thyroid problem

Thank You