icu 3

Question 1

Normal
respiration

Answer 1

Normal breathing is controlled by a
negative pressure system.

Question 2

Mechanical ventilation is delivered

Answer 2

by positive pressure; forcing
air into the lungs in one of two ways.
1. Invasively via an ETT or
tracheostomy tube
2. Non invasively via a mask delivering
PEEP or IPAP and EPAP

Question 3

§ Pulse oximetry uses

Answer 3

light absorption at
two wavelengths to determine
haemoglobin saturation.
§ Pulse oximetry is non-invasive and
provides immediate and continuous
data about SpO2

Question 4

Arterial Blood Gases

Answer 4

Blood test drawn from the arterial
blood
§ Give us information about a
patient’s acid-base balance which
is measured by the number of
hydrogen ions (H+) present in the
blood (pH)
§ Give us information about the
patient’s oxygenation status (PaO2
and SaO2)
§ Essentially gives us information
about the respiratory and
metabolic system
§ Give us information about how well
our body is compensating for a
disturbance in the acid-base
system

Question 5

Why ABG’s
instead of Sp02

Answer 5

§Pulse oximetry does not
assess ventilation (PaCO2) or
acid base status.
§Pulse oximetry becomes
unreliable when saturations
fall below 70%.
§Technical sources of error
(ambient or fluorescent light,
hypoperfusion, nail polish,
skin pigmentation and
others)
§Pulse oximetry cannot
interpret methaemoglobin or
carboxyhaemoglobin

Question 6

Basic
components of
ABG results

Answer 6

to an ABG reading
§pH
§SaO2
§PaO2
§PaCO2
§HCO3-
§Base excess/base deficit
Other component include
§Temperature
§Hb
§Base excess
§Some electrolyte values
like K+

Question 7

Value Arterial Range

Answer 7

pH 7.35 - 7.45
PaCO2 35-45 mm Hg
HCO3 22-26mEq/L
PaO2 80-100 mm Hg

Question 8

pH is the measure

Answer 8

of how acidic
or alkaline a solution is.
§ Measure of hydrogen ion (H+)
concentration
§ Every liquid has a pH value
which falls on a scale between 0-
14.
§ pH 7 = neutral
§ pH > 7 = alkaline
§ pH < 7 = acidic

Question 9

Airway Support

Answer 9

§ Most common loss of airway is due
to partial airway obstruction by the
tongue (due to oropharyngeal
relaxation)
§ Head tilt/chin list
§ Jaw thrust

Question 10

Devices to use in airway support

Answer 10

CPAP/BiPAP Mask
§ Oropharyngeal and
nasopharyngeal airway
§ Laryngeal mask airway (LMA)
§ Endotracheal tube
§ Tracheostomy tube

Question 11

Orotracheal Advantage

Answer 11

Easier access
* Avoids nasal and sinus
complications
* Allows for larger-diameter
tubes which facilitates;
* Work of breathing
* Suctioning
* Fibre optic bronchoscopy

Question 12

nasotracheal tube

Answer 12

• Easily secured and
  stabilised
• Reduce risk of
  unintentional extubation
• Well tolerated by patient
• Enables swallowing and
  oral hygiene
• Facilitates communication
• Avoids need for bite block

Question 13

Tracheostomy tubes

Answer 13

• Easily secured and
  stabilized
• Reduces rick on
  unintentional
  decannulation
• Well tolerated by patient
• Enables swallowing,
  speech, and oral hygiene
• Avoids upper airway
  complications
• Allows for largerdiameter tube, which
  facilitates
• Work of breathing
• Suctioning
• Fiberoptic
  bronchoscopy

Question 14

Airway Support why?

Answer 14

§Protect the airway
§Postoperative care
§Acute or chronic respiratory
failure
§Treat profound hypoxaemia
§Rest exhausted patients
§Avoid or control
hypercapnia