Electrocardiography

Question 1

What leads are most helpful when looking for a bundle-branch block?

Answer 1

V1
V6
I
And to some extent II
The QRS duration should be more than 120 ms to identify a bundle-branch block.

Question 2

is a wide QRS that arises from supraventricular conduction that is neither a typical RBBB nor a typical LBBB. It is often noted in patients with a cardiomyopathy.

Answer 2

Intraventricular conduction delay

Question 3

In V1 there is a broad, deep S wave (or QS wave), with ST segment elevation, that may be preceded by a very narrow R wave. What is the ECG interpretation?

Answer 3

LBBB

Question 4

ST elevation in V1 accompanying an inferior MI suggests?

Answer 4

Right ventricular involvement

Question 5

Patients with posterior MI often have ST depression where?

Answer 5

V1-V2

Question 6

What is ST-segment depression that occurs in patients with an ST-elevation MI.

Answer 6

Reciprocal change

Question 7

Shortening of the QT interval, with or without ST segment elevation suggests what?

Answer 7

Hypocalcemia

Question 8

Differential diagnosis of large R wave in V1 (5)

Answer 8

1. RVH
2. Post wall MI
3. N
4. WPW
5. Mm dystrophy

Question 9

This law essentially states that the intensity of transmitted light passing through a vascular bed decreases exponentially as a function of the concentration of the absorbing substances in that bed and the distance from the source of the light to the detector.

Answer 9

Beer-Lamber law

Question 10

A type of oximetry where light-emitting diodes (LEDs) transmit light through a vascular bed to a photodetector.

Answer 10

Transmission pulse oximetry

Question 11

An oximetry where LEDs transmit light that is reflected back to a photodetector on the same side of the vascular
bed as the LEDs.

Answer 11

Reflection pulse oximetry

Question 12

Is the most common form of pulse oximetry used in the operating room.

Answer 12

Transmission pulse oximetry

Question 13

Most pulse oximeters use 2 wavelengths namely?

Answer 13

660 nm (red) 
940 nm (infrared)

Question 14

Is the ratio of oxyhemoglobin to all the hemoglobin capable of carrying oxygen.

Answer 14

Functional hemoglobin

Question 15

Is the pulse oximeter a good indicator of ventilation?

Answer 15

pulse oximeter gives no indication of ventilation, only of oxygenation.

Question 16

Since the patient is oxygenated before anesthetic induction, if the pulse oximeter reaches 100%, does this indicate complete denitrogenation?

Answer 16

A reading of 100% in and of itself is not an accurate indication of denitrogenation.