Question 1

All of the following are potential hazards of using a heated humidifier during mechanical ventilation except:

Accepted Answer

Heated humidifiers are used in mechanical ventilation to add moisture to the air that the patient breathes, which helps to prevent the drying out of airways and the thickening of secretions. They do not increase dead space in the ventilatory circuit, which would lead to hypoventilation. The other options (A, B, and D) are potential hazards associated with the use of heated humidifiers.

Question 2

All of the following are features of an ideal heat-moisture exchanger (HME) except:

Accepted Answer

High compliance is not a feature of an ideal HME. Compliance refers to the ability of a device to expand and contract with changes in volume or pressure. HMEs are designed to be rigid and maintain their shape to ensure efficient heat and moisture exchange.

Question 3

The temperature of gas delivered to a patient's airway by a servo-controlled heated humidifier should not vary by more than how much?

Accepted Answer

The temperature of gas delivered to a patient's airway by a servo-controlled heated humidifier should not vary by more than 2° C to avoid potential harm to the patient.

Question 4

An ideal heat-moisture exchanger (HME) should have an efficiency rating of at least which of the following?

Accepted Answer

An ideal HME should have an efficiency rating of at least 90%. This means that it can recover at least 90% of the heat and moisture from the patient's exhaled breath and deliver it back to the inspired air. Any HME with a lower efficiency rating would not be as effective in preventing heat and moisture loss, which can lead to complications such as airway irritation, mucus plugging, and increased risk of infection. Therefore, a rating of 90% or higher is the best choice for an ideal HME.

Question 5

A patient receiving ventilatory support is being provided with humidification using a heat-moisture exchanger (HME). A physician orders a bronchodilator drug administered through a metered-dose inhaler (MDI) via the ventilator circuit. Which of the following must be performed to ensure delivery of the drug to the patient?

Accepted Answer

When administering a bronchodilator drug through an MDI via the ventilator circuit, it is necessary to remove the HME from the circuit to ensure that the drug is properly delivered to the patient. The HME can trap the medication particles and reduce their effectiveness. The other options listed are not applicable for drug delivery via an MDI.

Question 6

Which of the following methods are used to heat the gas delivered by a heated humidifier system?
I.using a wraparound heater (yoke or collar)II.placing a heating element in-line with gas flow
III.using a reservoir immersion heater
IV.placing a "hot plate" at humidifier base

Accepted Answer

Heated humidifier systems can use various methods to heat the gas, including a wraparound heater (yoke or collar) to heat the gas container, placing a heating element directly in-line with the gas flow, using a reservoir immersion heater to heat the water before it humidifies the gas, and placing a "hot plate" at the base of the humidifier to heat the water reservoir. All these methods are designed to ensure the gas is adequately humidified and warmed before delivery to the patient.

Question 7

Which of the following are necessary features to look for in selecting a heated humidifier?
I.water level readily visible
II.over-temperature protection
III.auditory and visual alarms
IV.minimal temperature overshoot

Accepted Answer

All listed features are important for the safety and effectiveness of a heated humidifier. Water level visibility ensures the device has enough water to function properly. Over-temperature protection and minimal temperature overshoot prevent the device from overheating, which could be dangerous. Auditory and visual alarms alert users to potential problems, such as low water levels or malfunctioning.

Question 8

A heated humidifier should trigger both auditory and visual alarms and interrupt power to the heater when the delivered temperature exceeds which of the following?

Accepted Answer

A heated humidifier should trigger both auditory and visual alarms and interrupt power to the heater when the delivered temperature exceeds 40° C to prevent potential harm to the patient.

Question 9

Which of the following automatic feed systems are used to regulate water levels when using a humidifier with a continuous feed system?
I.leveling reservoirs
II.flotation controls
III.optical sensors

Accepted Answer

All three options, leveling reservoirs, flotation controls, and optical sensors, are methods used to regulate water levels in systems with a continuous feed, such as humidifiers.

Question 10

For which of the following patients would you select a heated humidifier?
I.patient receiving oxygen through a bypassed upper airway
II.patient receiving long-term mechanical ventilation
III.patient receiving oxygen through an oronasal mask

Accepted Answer

Heated humidifiers are typically used for patients whose upper airway has been bypassed, as this prevents natural humidification of inspired air, and for those receiving long-term mechanical ventilation, to prevent the drying out of airways and to ensure the air is adequately humidified for lung health.

Question 11

Characteristics of a servo-controlled heated humidifier include all of the following except:

Accepted Answer

Servo-controlled heated humidifiers do not monitor heater temperature; they monitor and adjust the temperature of the gas being delivered to the patient.

Question 12

What are some potential problems with manually refilled heated humidifier reservoirs?
I.cross-contamination and infection
II.variable compliance or delivered volume
III.delivery of dry and/or hot gases

Accepted Answer

Manually refilled heated humidifier reservoirs can lead to cross-contamination and infection due to improper handling, variable compliance or delivered volume because of inconsistent refilling practices, and the delivery of dry and/or hot gases if the water level is too low or the heating element is unregulated.

Question 13

All of the following are true of heat-moisture exchangers (HMEs) except:

Accepted Answer

In-use HMEs can increase the resistance to breathing, especially at high flow rates.

Question 14

Conditions that can cause temperature "overshoot" with servo-controlled heated humidifiers include all of the following except:

Accepted Answer

Temperature "overshoot" with servo-controlled heated humidifiers can be caused by the unit warming up without flow, a decrease in flow during normal operation, or the airway temperature probe becoming dislodged. Refilling the unit reservoir with sterile water does not cause temperature overshoot; it is a regular maintenance activity.

Question 15

All of the following are potential hazards of using heat-moisture exchangers except:

Accepted Answer

Heat-moisture exchangers do not cause unintended tracheal lavage from condensate; this is more associated with active humidification systems.

Question 16

Which of the following is false about a simple heated humidifier (one that does not incorporate a servocontrol mechanism)?

Accepted Answer

Humidifier heating systems also have a controller that regulates the element's electric power. In the simplest systems, the controller monitors the heating element, varying the delivered current to match either a preset or an adjustable temperature. In these systems, the patient's airway temperature has no effect on the controller.

Question 17

What should happen when the remote temperature sensor of a heated humidifier becomes disconnected or fails?
I.	Power to the heater should be interrupted.
II.	Auditory and visual alarms should trigger.
III.	The unit’s outlet valve should lock closed.

Accepted Answer

When the remote temperature sensor of a heated humidifier becomes disconnected or fails, power to the heater should be interrupted to prevent overheating or underheating, and auditory and visual alarms should trigger to alert the user to the malfunction. Locking the unit’s outlet valve closed is not a standard response to this issue.

Question 18

All of the following are contraindications for heat-moisture exchangers except:

Accepted Answer

Heat-moisture exchangers are contraindicated in patients suffering from hyperpyrexia because they do not cool the inspired air and may lead to an increase in body temperature. The presence of thick, copious, or bloody secretions, a large leak around an artificial airway, and a high minute ventilation do not necessarily contraindicate the use of heat-moisture exchangers.

Question 19

When using a servo-controlled heated humidifier to deliver gas to an infant, the thermistor probe should be placed where?

Accepted Answer

The answer of When using a servo-controlled heated humidifier to...

Question 20

Where should you place the thermistor probe for a servo-controlled heated humidifier being used on a patient receiving mechanical ventilation?

Accepted Answer

The answer of Where should you place the thermistor probe...

Quiz 35: Humidity and Bland Aerosol Therapy

All of the following are potential hazards of using a heated humidifier during mechanical ventilation except:

All of the following are features of an ideal heat-moisture exchanger (HME) except:

The temperature of gas delivered to a patient's airway by a servo-controlled heated humidifier should not vary by more than how much?

An ideal heat-moisture exchanger (HME) should have an efficiency rating of at least which of the following?

Which of the following methods are used to heat the gas delivered by a heated humidifier system? I.using a wraparound heater (yoke or collar) II.placing a heating element in-line with gas flow III.using a reservoir immersion heater IV.placing a "hot plate" at humidifier base

Which of the following are necessary features to look for in selecting a heated humidifier? I.water level readily visible II.over-temperature protection III.auditory and visual alarms IV.minimal temperature overshoot

A heated humidifier should trigger both auditory and visual alarms and interrupt power to the heater when the delivered temperature exceeds which of the following?

Which of the following automatic feed systems are used to regulate water levels when using a humidifier with a continuous feed system? I.leveling reservoirs II.flotation controls III.optical sensors

For which of the following patients would you select a heated humidifier? I.patient receiving oxygen through a bypassed upper airway II.patient receiving long-term mechanical ventilation III.patient receiving oxygen through an oronasal mask