Questions on cardiac anesthesia (powered by I. Bulatov)

[Igor Bulatov]

Which of the following preventative actions is LEAST effective in decreasing the incidence of ventilator-associated pneumonia?


A. Changing ventilator circuits every five days.
B. Use of noninvasive ventilation techniques rather than intubation.
C. Keeping the head of the patient's bed elevated to 45 degrees.
D. Appropriate nurse/patient ratio.




A is the best answer.




Discussion


Multiple strategies have been recommended to prevent ventilator-associated pneumonia (VAP). The strategies are aimed at either decreasing bacterial colonization of the upper respiratory tract and stomach or decreasing aspiration of contaminated secretions and fluids.


There are also strategies to minimize the chance of aspiration. There is a definite association between tracheal intubation and the development of pneumonia. The use of noninvasive ventilation with full-face or nasal mask has been shown to decrease the development of VAP. When tracheal intubation is necessary, the duration of intubation should be kept as short as possible. This may involve a sedation regimen that minimizes oversedation and subsequent prolonged ventilation or a ventilator weaning protocol that takes early steps toward extubation. Keeping the head of the patient's bed elevated has been shown to decrease VAP. In a randomized trial, 45 degrees of elevation led to a threefold decrease in the incidence of VAP. Nursing and respiratory therapist staffing levels also affect VAP. Inadequate staffing is associated with the development of pneumonia and prolonged duration of stay. Frequent training in VAP prevention also appears to be important.


Although earlier recommendations from the Centers for Disease Control and Prevention were to change ventilator circuits on a scheduled basis, recent data support changing the circuits only when there is gross evidence of contamination. Less frequent manipulation of the ventilator circuit provides fewer opportunities for circuit contamination. Health care providers will also have less exposure to infectious aerosols that could be transmitted to other patients.





Reference


Kollef MH. Prevention of hospital-associated pneumonia and ventilator-associated pneumonia. Crit Care Med. 2004; 32:1396-1405.
Miller RD. Miller's Anesthesia. 6th ed. Philadelphia: Elsevier Churchill Livingstone; 2005:2796-2797.

[Alexey Dyachkov]

Игорь, когда же появятся новые вопросы?