Skip to main content Accessibility help
×
Home
Hostname: page-component-59b7f5684b-vcb8f Total loading time: 0.556 Render date: 2022-09-26T10:20:10.528Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "useRatesEcommerce": false, "displayNetworkTab": true, "displayNetworkMapGraph": false, "useSa": true } hasContentIssue true

Chapter 23 - Modes of mechanical ventilation

Published online by Cambridge University Press:  05 July 2014

Kamen Valchanov
Affiliation:
Papworth Hospital
Jane Sturgess
Affiliation:
Addenbrooke’s Hospital, Cambridge
Justin Davies
Affiliation:
Addenbrooke’s Hospital, Cambridge
Kamen Valchanov
Affiliation:
Papworth Hospital, Cambridge
Get access

Summary

Mechanical ventilation is used during surgery or respiratory failure to optimise gas exchange until the end of surgery or while waiting for the improvement of the underlying respiratory disease.

Modern mechanical ventilation involves positive pressure insufflation of gas into the lungs rather than negative pressure generated by the respiratory muscles, and is therefore harmful by default. However, short spells of mechanical ventilation during anaesthesia and surgery seem to be well tolerated by the majority of patients without major side effects.

Positive pressure ventilation of the lungs causes a number of undesirable side effects which can lead to lung injury, even in healthy lungs. These can sometimes lead to multiorgan dysfunction or failure (Figure 23.1).

For this reason the least harmful mode of mechanical ventilation until the end of surgery or respiratory failure recovery is likely to yield most patient benefit.

Mechanical ventilation can be non-invasive (through face masks or hoods), or invasive (through tracheal or bronchial tubes, or tracheostomy).

Both modes of mechanical ventilation employ the same principles, but non-invasive ventilation:

  • Does not require sedation

  • Can be done at home

  • Does not impair the mucociliary apparatus

Continuous positive airways pressure (CPAP) is not per se a mode of mechanical ventilation, but often used as such. It involves administration of positive pressure throughout the respiratory cycle (inspirium and expirium) but the patient has to generate negative pressure to inflate the lungs. This mode is least invasive, and efficient for:

  • Improving pulmonary oedema (by increasing the intra-alveolar pressure during expirium and reducing the work of breathing)

  • Improving oxygenation

  • Improving lung collapse and atelectasis

Type
Chapter
Information
Publisher: Cambridge University Press
Print publication year: 2014

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Gatinoni, L, et al. Towards ultraprotective mechanical ventilation. Curr Opin Anesthesiol 2012; 25.
Gatinoni, , et al. Ventilator-induced lung injury: anatomical and physiological framework. Crit Care Med 2010; 38: S539–48.CrossRefGoogle Scholar

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×