RESPIRATORY

TYPE 2 RESPIRATORY FAILURE

Introduction

5 min

Introduce yourself and the group

Provide rationale for the session and relevance to clinical practice

Outline learning objectives:

Define type two respiratory failure and explain the pathogenesis using concepts of ventilation
Recognise type two respiratory failure on an arterial blood gas
Suggest common causes of type two respiratory failure
Understand principles of supportive management in relation to type two respiratory failure including non-invasive ventilation, controlled oxygen therapy and invasive ventilation

Explain structure of session

Total time:

60 min

Number of students:

1-5

Grade of students:

3rd to 5th year medical students

Created by:

Dr Charlotte Hayden

Uploaded:

10th February 2020

Last updated:

10th February 2020

Resources needed for this session:

Pen, paper, whiteboard or flipchart paper if possible

Students can scan the QR code opposite to view all investigation results on their phone as you work through the session.

Resources linked to this session:

Arterial Blood Gas (Procedure)

Activity 1: Recap Knowledge

10 min

Ask the student(s) to suggest a definition for type two respiratory failure.

Encourage them to consider five common causes of type two respiratory failure and consider what they all have in common. Revise concepts of ventilation and carbon dioxide/oxygen diffusion across the alveolar barrier. How does this differ from the mechanism behind type one respiratory failure?

Activity 2: History Taking and Clinical Examination

20 min

Ask the student(s) to take a focused history and perform a focused examination on a patient with a respiratory condition that is causing, or could potentially cause, type two respiratory failure.

Ask them to present the key positive and negative findings of the case (max 1 minute).

Activity 3: Arterial Blood Gas Interpretation

10 min

Allow the student(s) to review the patient's arterial blood gas results (if available and demonstrates type two respiratory failure). If none is available, use the example opposite,

ABG (on air)

pH 7.35

pO₂ 7.1kPa (10-13.3kPa)

pCO₂ 6.9kPa (4.67-6.00kPa)

HCO₃^- 29mmol.l^-1 (22-26mmol.l^-1)

Activity 4: Further Management

10 min

If relevant, allow the students to review the notes for the patient they have seen. Ask them to consider what treatments have been given.

Discuss:

What treatments have been given that are specific/treating the underlying cause?
What management has been given to support the patient?
What means of oxygen delivery to you know of? What might be appropriate for this patient?

Consider the scenario that the patient deteriorates and their oxygen requirement increases. Review the ABG opposite.

What supportive treatment might be required for this patient?
How might this be delivered?
What are the indications for intensive care?

If possible, introduce students to a BIPAP machine. Demonstrate the key areas and define terms including IPAP, EPAP, tidal volume and FiO₂.

Encourage the group to consider suitability for invasive ventilation and high-dependency care. How might this decision be made in practice? Consider discussing the relevance of DNACPR and TEPP forms.

ABG (on 60% oxygen)

pH 7.21

pO₂ 8.2kPa (10-13.3kPa)

pCO₂ 9.1kPa (4.67-6.00kPa)

HCO₃^- 32mmol.l^-1 (22-26mmol.l^-1)