Difference between revisions of "Electrolyte Disorders"

From ECGpedia
Jump to navigation Jump to search
m (Hypocalcemia)
 
(14 intermediate revisions by the same user not shown)
Line 4: Line 4:
 
|supervisor=  
 
|supervisor=  
 
}}
 
}}
==Hypercalcemia==
 
Hypercalcemia, high blood calcium, speeds repolarization. Characteristics of hypercalcemia:
 
*Mild: broad based tall peaking T waves
 
*Severe: extremely wide QRS, low R wave, disappearance of p waves, tall peaking T waves.
 
 
==Hypocalcemia==
 
ECG-characteristics of hypocalcemia, low blood calcium:
 
*Narrowing of the QRS complex
 
*Reduced PR interval
 
*T wave flattening and inversion
 
*Prolongation of the QT-interval
 
*Prominent U-wave
 
*Prolonged ST and ST-depression
 
 
 
==Hyperkalemia==
 
==Hyperkalemia==
 
ECG characteristics of hyperkalemia, high blood potassium:
 
ECG characteristics of hyperkalemia, high blood potassium:
*Tall peaked T waves
+
*P-waves are widened and of low amplitude due to slowing of conduction
*Flattening p-waves. In extreme hyperkalemia p-waves may disappear altogether.
+
*QRS complex:
*Prolonged depolarization leading to QRS widening (nonspecific intraventricular conduction defect) sometimes > 0.20 seconds
+
**QRS widening
 +
**fusion of QRS-T
 +
**loss of the ST segment
 +
*Tall tented T waves
 +
 
 +
The initial part of the QRS complex is often spared as purkinje fibers are less sensitive to hyperkalemia.
 +
These changes can also occur in acidosis (via the same mechanism) and during Class IC anti-arrhythmic intoxication.
  
 
At concentrations > 7.5 mmol/L atrial and [[Ventricular Fibrillation|ventricular fibrillation]] can occur.
 
At concentrations > 7.5 mmol/L atrial and [[Ventricular Fibrillation|ventricular fibrillation]] can occur.
Line 29: Line 21:
 
Image:KJcasu18-2.jpg|Consecutive ECGs of a patient with hyperkalemia. ECG2
 
Image:KJcasu18-2.jpg|Consecutive ECGs of a patient with hyperkalemia. ECG2
 
Image:KJcasu18-1.jpg|Consecutive ECGs of a patient with hyperkalemia. After correction of potassium levels. ECG3
 
Image:KJcasu18-1.jpg|Consecutive ECGs of a patient with hyperkalemia. After correction of potassium levels. ECG3
 +
File:DVA0578.jpg|Another patient, potassium of 9.4 mmol/L
 +
File:E000561.jpg|Potassium 7.5 mmol/L. [[Answer_-_Case_of_the_month_(Oct_2011)|More ECGs]]
 
</gallery>
 
</gallery>
 
{{clr}}
 
{{clr}}
Line 38: Line 32:
 
*A U-wave may be visible
 
*A U-wave may be visible
 
<gallery>
 
<gallery>
 +
Image:Hypokalemia.jpg| A patient with hypokalemia, prominent QT prolongation. Not the extrasystoles originating from the prolonged T/U wave. This patient definitely needs rhythm monitoring
 
Image:KJcasu17-1.jpg| patient A
 
Image:KJcasu17-1.jpg| patient A
 
Image:KJcasu17-2.jpg| patient A
 
Image:KJcasu17-2.jpg| patient A
Line 44: Line 39:
 
</gallery>
 
</gallery>
 
{{clr}}
 
{{clr}}
 +
 +
==Hypercalcemia==
 +
Hypercalcemia, high blood calcium, speeds repolarization. Characteristics of hypercalcemia:
 +
*Mild: broad based tall peaking T waves
 +
*Severe: extremely wide QRS, low R wave, disappearance of p waves, tall peaking T waves.
 +
<gallery>
 +
File:E000546.jpg|A patient with severe hypercalcemia: Calcium 4.6 mmol/L, albumin 37 g/L
 +
</gallery>
 +
 +
==Hypocalcemia==
 +
ECG-characteristics of hypocalcemia, low blood calcium:
 +
*Narrowing of the QRS complex
 +
*Reduced PR interval
 +
*T wave flattening and inversion
 +
*Prolongation of the QT-interval
 +
*Prominent U-wave
 +
*Prolonged ST and ST-depression
 +
<gallery>
 +
File:E000800.jpg|An ECG of a patient with hypocalcemia
 +
</gallery>

Latest revision as of 12:23, 3 September 2014

Author(s) J.S.S.G. de Jong
Moderator T.T. Keller
Supervisor
some notes about authorship

Hyperkalemia

ECG characteristics of hyperkalemia, high blood potassium:

  • P-waves are widened and of low amplitude due to slowing of conduction
  • QRS complex:
    • QRS widening
    • fusion of QRS-T
    • loss of the ST segment
  • Tall tented T waves

The initial part of the QRS complex is often spared as purkinje fibers are less sensitive to hyperkalemia. These changes can also occur in acidosis (via the same mechanism) and during Class IC anti-arrhythmic intoxication.

At concentrations > 7.5 mmol/L atrial and ventricular fibrillation can occur.


Hypokalemia

Hypokalemia, low blood potassium, results in:

  • ST depression and flattening of the T wave
  • Negative T waves
  • A U-wave may be visible


Hypercalcemia

Hypercalcemia, high blood calcium, speeds repolarization. Characteristics of hypercalcemia:

  • Mild: broad based tall peaking T waves
  • Severe: extremely wide QRS, low R wave, disappearance of p waves, tall peaking T waves.

Hypocalcemia

ECG-characteristics of hypocalcemia, low blood calcium:

  • Narrowing of the QRS complex
  • Reduced PR interval
  • T wave flattening and inversion
  • Prolongation of the QT-interval
  • Prominent U-wave
  • Prolonged ST and ST-depression