Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Principles I > Environmental Safety > Flashcards

Environmental Safety Flashcards

0
Q

Define voltage.

A

The pressure pushing electrons

*compares to contractility of the heart in the circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What is the normal frequency used for alternating current (AC) around the world?

A

60 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define circuit.

A

Path that current flows through.

*Similar to the blood vessels of the circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define ohm.

A

The measure of resistance (skin)

*similar to SVR in the circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define hertz.

A

Number of cycles per second

*similar to heart rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define Amps.

A

The amount of current flow per second

*similar to cardiac index

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define current.

A

The flow of electrical charges (electrons)

*compares to blood flow in the circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe frequency.

A
  • measured in Hertz (Hz)
  • the higher the frequency, the less dangerous
  • frequencies between 0-1 Hz can interfere with depolarization and repolarization in the myocardium causing arrhythmias
  • frequency at which minimum current induces fibrillation is 50-60 Hz which is the normal AC frequency used worldwide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe alternating current (AC).

A
  • variation in electron density within the conductor is time dependent
  • intermittent current

Ex: 60 Hz means the current goes from high electron density to low electron density back to high in approx 1/60 sec or 60 times per second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define conductor.

A

Material that current moves through easily

  • good conductors are copper and bronze
  • water is a great conductor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define insulator.

A

Substance/material that current moves through poorly

ex: glass and air are poor conductors
* skin is a poor conductor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe skin as a conductor.

A
  • skin is very resistant to current flow and a poor conductor
  • as current flows through skin, resistance decreases
  • dry, healthy, intact skin is 1 million ohms
  • perspiring, intact skin is 12,000 ohms
  • conducting jelly decreases skin ohms to 1,000
  • catheter/pacing wires bypass the skin and go into the body fluid decreasing ohms to <100
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does electricity work?

A

A specific amount of alternating current (amp) is pushed through a circuit by voltage (120v) at a specified frequency (60 Hz)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe current flow.

A
  • Current can flow through an unbroken closed circuit

- travels the path of least resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe electrical resistance.

A
  • impedance of flow
  • can lead to storage of charges (capacitor)
  • long power cords cause higher resistance *leading to pressure build up and current leaks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe leakage current.

A

Current can escape the designated circuit and travel an alternative path

  • high resistance can lead to leakage current due to excess pressure in the circuit and the currents desire to escape to a path of lower resistance and pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define current density.

A

The amount of current and area it flows over.

*similar to HCT or viscosity

17
Q

What are the three wires of a circuit?

A
  • hot wire: supplies the current
  • neutral wire: provides a return path
  • ground wire: provides a low resistance path for leakage current to flow away from electrical equipment
18
Q

What is the function of a circuit breaker?

A

To interrupt the circuit when current flow is too high

-protects from overheating and fire

19
Q

Describe microshock.

A
  • current is applied directly to heart
  • small amounts of voltage or current applied directly to myocardium bypassing skin via IV cath, pacer wires, etc
  • current as little as 100 micro amps can cause fatal arrhythmias
20
Q

Describe macroshock.

A
  • current is applied directly to the body surface
  • requires a large amount of current to overcome skin’s resistance
  • can cause muscle contraction, pain, burns, open wounds, pacer disruption, arrhythmias
21
Q

What effects can 100-2500 milliamps at 60 Hz have?

A

V-fib

22
Q

What effects can over 6,000 milliamps at 60Hz have?

A
  • sustained myocardial contraction
  • respiratory paralysis
  • burns if the current density is high
23
Q

What effect can 50-100 milliamps at 60 Hz have?

A
  • pain

- mechanical injury

24
Q

What is the function of the line isolation monitor (LIM)?

A
  • measures current flowing out and in, determining the difference or the amount of current leaking
  • alarm indicates current is no longer isolated and unsafe leakage current may be present
  • usually indicates either the last piece of equipment plugged in may have a fault or too much equipment is being used simultaneously resulting in too much leakage current
25
Q

Describe electrosurgical units (ESU).

A
  • electrical current used to cauterize vessels and cut tissue
  • uses high frequencies between 300 kHz and 2MHz
  • two type: unipolar and bipolar
26
Q

Describe unipolar ESU.

A

The current is applied using a single electrode that returns to the ESU by way of a dispersal pad (Bovie or grounding pad)

27
Q

Describe bipolar ESU.

A

-involves use of a two pronged cutting electrode instrument
-the current travels only between the two prongs
*used when unipolar is unsafe:
brain, ovarian, Fallopian tube surgeries

28
Q

Describe a dispersal pad.

A
  • Bovie or grounding pad
  • should be applied as close as possible to surgical site, large surface area to minimize current density
  • pad must be in good contact
  • takes current back to Bovie box
29
Q

What effects can ESU have on pacemakers?

A
  • ESU current traveling through pacer can alter functioning
  • pacer can be tricked if the current flows through the pacer and it will not pace
  • if 100% paced, the patient will go asystole
  • Place the Bovie pad close to the surgical site
  • Use a bipolar cautery
  • magnet may be needed- causes pacer to go into an asynchronous mode and it will fire without sensing
30
Q

What effects do ESU have on automatic implantable cardiac defibrillators (AICD)?

A

The ESU current will trigger the AICD to fire so the device should be turned off prior to surgery

31
Q

How far should the surgical site be from the pacemaker?

A

Beyond 15 cm

32
Q

Define antiseptics.

A

Antibacterial agents applied to living tissue

33
Q

Define disinfectants.

A

Antibacterial agents applied to non-living objects

34
Q

Describe hydrogen peroxide.

A

An antiseptic for skin

*if splashed in the eyes may cause corneal ulceration

35
Q

Describe iodine.

A

Antiseptic used on skin

  • if splashed in the eyes, may cause irritation
  • if a facial surgery and site cleansed with iodine, first border the patient’s eyes with saline or petroleum gauze to protect
36
Q

Describe chlorhexidine.

A

Antiseptic to clean skin

*if splashed in the the eye can cause keratitis or loss of vision

37
Q

Describe chlorine bleach.

A

Disinfectant

*vapors may irritate the respiratory tract

38
Q

Describe ammonia.

A

Disinfectant

*vapors irritate eyes and respiratory tract

39
Q

What are some potential hazards in the OR?

A

Back strain
Falls
Contamination with infectious materials

Principles I (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions