The document discusses hyperkalemia, its effects on the electrocardiogram (ECG), and the role of calcium gluconate in reversing these effects. Hyperkalemia is a potentially lethal condition defined as a serum potassium level above 5 mEq/L. It can cause abnormal heart rhythms and cardiac arrest. On ECG, hyperkalemia presents as tall, peaked T waves and prolonged PR interval. Calcium gluconate works by antagonizing the effects of potassium at the cellular level and restoring the normal threshold potential, allowing action potentials to occur and reestablishing normal cardiac conduction. By rapidly shifting potassium into cells, calcium gluconate can quickly reverse the ECG changes and cardiac effects caused by hyperkalemia

1. The role of Ca-gluconate in
reversing hyperkalemia
effects
&

2.  Cardiac conduction system .
 Cardiac cell action potential .
 Normal ECG .
 Hypo/Hyperkalemia & their effect on ECG .
 Using Ca-gluconate to reverse
hyperkalemia effect .
 Treatment of hyperkalemia .
 Conclusion .
 References .

3. Sinoatrial node
AV node
A-V bundle
Bundle Branches
Purkinje fibers

5. Na+
Ca2+
Extracellular K+
3Na+
2K+
K+
K+
Voltage gated
Na channel
Voltage gated
K channel
L-Ca
channel

6.  Definition .
 Study of waveform .
 We can identify by ECG ….

8. ECG or EKG :
is a representation of the electrical events of
the cardiac cycle .
 The study of waveform can lead to greater
insight into a patient’s cardiac patho-physiology.
Def.

9. • QRS – Ventricular
depolarization
• P-wave – Atrial
depolarization
• T-wave – Ventricular
repolarization

10. The PR Interval
Atrial depolarization
+
delay in AV junction
The QT Interval
Depolarization &
repolarization of
ventricle
The ST segment
Period when
ventricular
depolarized

11.  Arrhythmias .
 Myocardial ischemia and infarction .
 Pericarditis .
 Chamber hypertrophy .
 Electrolyte disturbances ( K+,Na+,Ca2+ ..etc )
 Drug toxicity (Ex. Digoxin )

13.  In many metabolic processes e.g. ( Regulation
of protein and glycogen synthesis ) .
 Maintain osmotic and acid-base balance
between intra and extra cell .
 Maintain resting membrane potential of
cellular membrane .

14. • The presence of potassium
in the blood .
• Normal range : 3.5 – 5 mEq/L

15.  Hypokalemia
serum potassium level < 3.5 mEq/L
 Severe hypokalemia
serum potassium < 2.5 mEq/L

16. 1- Transcellular movement into cells
a. Alkalosis ( increase pH )
2- Reduce intake K+
3- loss from GIT
a. Laxatives
b. Chronic diarrhea
c. Persistent vomiting
4- Loss in urine
a. Diuretics
b. Cushing syn.
c. Conn’s syn.

17. Clinical features
A small drop in potassium level often does not
cause symptoms, which may be mild, and may
include :
 Muscle weakness
 Hypotonia
 Constipation
 Depression & Confusion
 Increase toxicity of digoxin

18. 1. Slightly prolonged PR interval
2. Flattened T wave
3. Presence of U waves (in most of leads)
4. ST depression ( in severe cases )

20. ST-segment

21.  Hyperkalemia
serum potassium level < 5 mEq/L
 Severe hyperkalemia
serum potassium < 7 mEq/L
Pseudo-Hyperkalemia
 Occur due to destruction of RBCs in delayed
investigated blood sample .

22. 1- Increase intake K+
all meats, some types of fish (such
as salmon, cod ), and many fruits,
vegetables, and legumes..
2-Impaired excretion of K+
a. Acute & chronic renal failure
b. Addison disease
c. ACEI + K sparing diuretics
3- Transcellular movement out cells
a. Hemolysis
b. DKA

23. Clinical features
 Abnormal heart rhythms (arrhythmias) .
 Hyperkalemia may lead cardiac arrest
if the level exceed 7 mEq/L

24. 1) Tall peaked T wave with narrow base .
2) QT shortened .
3) Prolong PR interval ( bundle branch block )
4) Widening QRS complex ( more than 3 small boxes )
5) Sometimes loss of P wave

27.  Why Calcium ??
 Calcium antagonizes the effects of hyperkalemia at
the cellular level and actually increases the
threshold potential (i.e.- from -75 mV to -65 mV)
 Calcium allows for an action potential to occur at a
more physiologic level and actually re-establishes
the normal gradient .

28.  Calcium salts
• Calcium chloride ??!!!!
• Calcium gluconate
 Why Ca-gluconate use ?!
 Calcium chloride
 Has greater bioavailability & three times more potent than the
other formulation, (calcium gluconate)
 The onset of action with both agents CaCl2 &
Ca-gluconate is less than three minutes
However
calcium chloride is also more irritating & if given too rapidly ,
It can lead to infiltration and possible loss of the
intravenous site.

29.  Calcium Salts :
Reduces the risk of ventricular fibrillation caused by
hyperkalemia .
 Insulin administered with glucose :
50g glucose with 20 unit insulin ( lower serum K level
within 30 min.) increasing shift of K into cell .
 Beta 2-adrenergic agonists :
Promote cellular reuptake of potassium .
 Diuretics : ( loop , thiazide )
Cause potassium loss through the kidney .

30.  Binding exchange resins : ( polystyrene cation )
Promote the remove of potassium form the body .
 Alkalinizing agents : ( bicarbonate )
Increases the pH, which results in a temporary
potassium shift from the extracellular to the
intracellular environment; these agents
enhance the effectiveness of insulin in
patients with acidemia .

31.  Potassium is
very important mineral for the
proper function of all cells, tissues in the
human body .
crucial to heart function and plays a
key role in skeletal and smooth muscle
contraction.

32.  The hyperkalemia is common, silent, and
potentially lethal clinical condition, it is
difficult to avoid patients with hyperkalemia .
◦ This electrolyte imbalance is seen in both inpatient
and outpatient settings in alarming numbers.
 However, is the ability to appropriately treat
hyperkalemia and avoid fatal arrhythmias.

33.  https://med.uth.edu/internalmedicine/files/2
013/10/11-Hyperkalemia-A-Potential-
Silent-Killer.pdf
 http://www.mayoclinic.org/symptoms/hyper
kalemia/basics/causes/sym-20050776
 http://www.livestrong.com/article/458069-
calcium-gluconate-in-hyperkalemia/
 http://lifeinthefastlane.com/ecg-
library/basics/hypokalaemia/

34.  http://lifeinthefastlane.com/hyperkalemia/
 http://umm.edu/health/medical/ency/articls
/high-potassium-levels
 http://emedicine.medscape.com/article/766
479-overview
 http://lifeinthefastlane.com/ccc/calcium-
digoxin-toxicity-and-stone-heart-theory/

35. Supervised by :
Dr-Hala Zakaria Alagha