IV sedation I

Question 1

What ways can we monitor the respiratory system during sedation?

Answer 1

Basic clinical signs
* Respiratory rate
10 – 18 per minute
* Depth of breathing
* Pattern of breathing
* Cyanosis

Advanced
* Pulse oximetry
(mandatory)
* Carbon dioxide monitoring
(Optional)

Question 2

What type of communication is maintained throughout conscious sedation?

Answer 2

verbal communication

Conscious sedation, a technique in which use of drugs produces depression of nervous system enabling treatment to carried out, but during which verbal communication is maintained throughout the period of sedation

Question 3

What are the limitations of pulse oximetry?

Answer 3

Limitations:
* Ambient light
* Movement
* Cold peripheries
* Nail varnish
* Measurement lag

Question 4

What is capnography?

Answer 4

• Detects exhaled CO2 in breath
• Usually via nasal prongs
• Waveform displayed on a monitor
• Allows confirmation of adequate ventilation and an open airway
• Patient has to be breathing through their nose!

Question 5

what are the respiratory complications during sedation?

Answer 5

Upper Airway Obstruction –> Hypoventilation

Question 6

what happens during a upper airway obstruction?

Answer 6

sedation leads to decreased muscle tone causing collapse of tongue on to wall of pharynx (called pharyngeal collapse)

Mild cases lead to partial airway obstruction
More severe leads to complete obstruction

Question 7

what are the signs of airway obstruction?

Answer 7

Signs of airway obstruction
* Snoring
* Stridor
* Drop in O2 saturations
* Loss of CO2 trace
* Seesaw respiration

Question 8

what is the management of an airway obstruction?

Answer 8

Management
* Supplementary oxygen
* Careful titration of sedation
* Basic airway opening maneuvers
* Airway adjuncts

Question 9

How to sedative drugs cause hypoventilation?

Answer 9

• Sedative drugs also sedate the Respiratory center in the brain
• Also reduce receptor sensitivity to CO2
• Leads to reduced respiratory rate or complete cessation of breathing
• CO2 levels can build up leading to narcosis

Question 10

What is hypoventilation?

Answer 10

breathing that is too shallow or too slow to meet the needs of the body. If a person hypoventilates, the body’s carbon dioxide level rises. This causes a buildup of acid and too little oxygen in the blood. A person with hypoventilation might feel sleepy.

Question 11

How do you detect if someone is hypoventilating?

Answer 11

• Monitoring of respiratory rate (increased)
• Drop in Oxygen saturation

Question 12

How is hypoventilation managed?

Answer 12

1. Reversal of sedation with Flumazenil or Naloxone
2. Assisted ventilation with self-inflating ambubag (bag - valve - mask)

Question 13

What ways can we monitor the cardiovascular system during sedation?

Answer 13

Basic clinical signs
* Heart rate (from pulse oximeter)
* Heart rhythm
* Conscious level
* Skin colour
* Capillary refill

Advanced
* Non-invasive blood pressure (Mandatory)
* ECG monitoring (Optional)

Question 14

Explain the use of non-invasive blood pressure (NIBP) in sedation?

Answer 14

• Automated machines
• Cuff around arm or calf
• Automatic cycling – every 5 minutes
• Mandatory when giving a sedative technique

Question 15

what is NIBP affected by?

Answer 15

– Movement
– Wrong size cuff

Question 16

When should ECG monitoring be used when sedating?

Answer 16

in patients with a history of significant cardiovascular disease

Question 17

what can a ECG detect?

Answer 17

• Can detect arrhythmias and also signs of cardiac ischaemia and infarction
• Usually a 3-lead configuration

Question 18

what are cardiovascular complications when sedating?

Answer 18

• Hypotension
• Cardiac Arrhythmias
• Cardiac Arrest

Question 19

How is hypotension caused during sedation?

Answer 19

Causes:
* Vasodilation caused by sedative drugs
* Some drugs decrease the strength of heart contraction
* Dose related
* More likely to occur in the elderly, and those with existing cardiovascular disease

Question 20

How is hypotension treated during sedation?

Answer 20

Treatment:
* Prevention better than the cure!
* Stop administering agent
* Place patient head down and with feet elevated
* IV fluids may be required

Question 21

How is cardiac arrhythmias caused during sedation/ risk factors?

Answer 21

• Multi-factorial aetiology
• May be precipitated by adrenaline in LA
• More likely in elder and those with CVS disease
• Raised blood CO2 levels also increase risk

Question 22

How is cardiac arrhythmias treated during sedation?

Answer 22

• Call for expert help
• ALS standard algorithms (ALS – advanced life support)
  
  • ABCDE
  • give o2 if appropriate (monitor vitals)
  • follow ALS flowchart

—> if pt goes into cardiac arrest CPR 30:2 with defibrillator needed

Question 23

What can cause respiratory complications during IV sedation?

Answer 23

Decreased muscle tone
Body not expelling enough CO2