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Note added at 39 mins (2014-12-03 11:53:15 GMT)
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However, bucking the ventilator (trying to exhale when the ventilator is delivering a breath) may be increased

http://books.google.com.ua/books?id=SmtjSD1x688C&pg=PA655&lp...

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Note added at 40 mins (2014-12-03 11:54:54 GMT)
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“bucking” (breathing out of phase ...

http://books.google.com.ua/books?id=nmC6zkS0IDIC&pg=PT98&lpg...

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Note added at 42 mins (2014-12-03 11:56:28 GMT)
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A 75 year old man is on mechanical ventilation due to stroke which involved his 9th and 10th cranial nerves. His notes indicated "bucking". What is meant by bucking the ventilator.
(a) Patient is biting the endotracheal tube
(b) Endotracheal tube is displaced
(c) Patient's respiratory effort coordinating poorly with the ventilator.
(d) Low FiO2

Answer: The answer is (c). Asynchronous breathing occurs when the patient's breathing poorly coordinates with the ventilator. This is referred to as bucking the ventilator. This can be adjusted by modifying the mode of ventilation, rate, tidal volume and PEEP. Sedation should be attempted if these measures fail.

http://www.superscore.com/superscore/site/ventilation4.htm