Clinical Case #4Rita Brar

March 8th, 2007

A 70 year old female went to the ER due

to frequent fainting spells. She was diagnosed to have hypertension and is on

Metoprolol 50mg BID for 2 years. At the ER the following vitals were noted:

BP: 100/70 ----------------- Hypotensive

Cardiac rate: 50/min ---- Bradycardia

Fainting= “Syncope”• Definiton:

Loss of consciousness is interruption of one's awareness of self and surroundings. When loss of consciousness is temporary and recovers spontaneously it is referred to as fainting or syncope.

• Pathophysiology:

Result of a temporary reduction in the blood flow (and, therefore, oxygen) to the brain. This can lead to lightheadedness or a "black out" episode of loss of consciousness. Impairment in the brain's blood supply.

Metaprolol

• “Beta-adrenergic blocking agent”

• Beta blockers reduce blood pressure. Beta blockers work by blocking the effects of the hormone epinephrine, also known as adrenaline. As a result, the heart beats more slowly and with less force, thereby reducing blood pressure. Beta blockers also help blood vessels relax(dilate) and open up to improve blood flow.

Metaprolol• Beta-blockers are drugs that bind to beta-

adrenoceptors and thereby block the binding of norepinephrine and epinephrine to these receptors. This inhibits normal sympathetic effects that act through these receptors. Therefore, beta-blockers are sympatholytic drugs. Some beta-blockers, when they bind to the beta-adrenoceptor, partially activate the receptor while preventing norepinephrine from binding to the receptor.

• Side Effects:• Bradycardia

• Fatigue

• Lightheadedness

• Cold Extremities

• Memory Loss

• Hypotension

Primary Diagnosis

• Patient’s fainting is caused by side effects of the Metaprolol because of decrease in blood pressure which decreases the oxygen content to the brain and therefore causes loss of conciousness.

Differential Diagnosis• Brain Tumor• Parkinson’s Disease(No associated signs/symptoms in patient)

• Dehydration

Treatment and Plan

• Stop the patient’s Metaprolol for few days to see if the fainting dissapears as a confirmatory method

• Change the medication to Pindolol, Acebutolol, or Penbutolol- because these are only partial agonists they depress cardiac output or heart rate less than other beta-blockers. The following drugs are significantly a greater agonist than antogonist on the beta2-adenoreceptors.

Laboratory Exams• Echocardiogram – A device called a transducer is placed on the chest and

sound waves are bounced off the heart. This provides a “moving” picture of the heart and the heart valves as well as information about how the heart is pumping.

• Electrocardiogram (ECG) – A test that records the electrical activity of the heart using electrode patches with wires attached to them that are placed on a person’s chest, arms, and legs. The wires are connected to a monitor, which captures the ECG. The test takes a few minutes.

• Electroencephalogram (EEG) – A test that records brain wave activity to help determine if and/or where seizures may occur.

• Electrophysiology (EP) study – A procedure that reproduces abnormal heart rhythms and extra heartbeats to interpret the heart’s electrical impulses and responses to the heartbeats. To get a reading, catheters are threaded into the heart. The procedure lasts about two hours

• Tilt table – A procedure that tries to recreate the conditions that cause fainting. An individual lies on a table that tilts by varying angles. While on the table the person is connected to a machine, which allows the doctor to measure how blood pressure, heart rate, and heart rhythm respond to changes in body position. The procedure takes about two hours.

• CT Scan- for the differential diagnosis of brain tumor

Thank You For Your Attention!