Critically evaluate the role of the prone position in critically ill patients.
The prone position has a number of obvious potential advantages to critically ill patients. These include enhancing the ability to rest and dress soft tissue injuries (including burns, skin grafts, plastic surgical flaps etc). The majority of ICU interest however relates to the potential ventilatory benefits associated with prone positioning: increased homogeneity of ventilation, improved ventilation:perfusion matching, increased Functional residual capacity, reduced atelectasis, and facilitation of drainage of secretions. Improved gas exchange is seen in approximately 2/3 of patients, and these improvements are persistent in some. A prospective randomised study confirmed these improvements in oxygenation in patients with Acute Lung Injury/ARDS, but was unable to demonstrate any short or long term mortality benefits. Many details are still under much discussion (e.g. which groups should be “proned”, when in their course, duration of time left prone, and for how many days to persist with prone positioning). Unfortunately, positioning patients prone is not without problems: expertise, manpower and time required for turning; potential for dislodgement of lines/tubes; problems with airway access; increased number of new pressure sores; increased new pressure sores in prone-related areas; increased intracranial pressure and decreased tolerance of enteral feeding. (Gattinoni L et al. N Engl J Med 2001; 345:568-73; Broccard AF. Chest 2003;
123:1334-6; Beuret P et al. Intensive Care Med 2002; 28 :564-69).
Prone positioning is seldom seen during one's ICU practice as a junior, but one takes notice of it when it happens.
Rationale for prone ventilation
Limitations of prone ventilation
Evidence in support of prone ventilation
The college answer also quotes an optimistic review paper by Alain Broccard from 2003. Its overall tone was "don't write proning off just yet, the jury is still out".
More modern data in support of prone ventilation:
Mancebo, Jordi, et al. "A multicenter trial of prolonged prone ventilation in severe acute respiratory distress syndrome." American journal of respiratory and critical care medicine 173.11 (2006): 1233-1239.
Gattinoni, Luciano, et al. "Effect of prone positioning on the survival of patients with acute respiratory failure." New England Journal of Medicine 345.8 (2001): 568-573.
Sud, Sachin, et al. "Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis." Intensive care medicine 36.4 (2010): 585-599.
Beuret, Pascal, et al. "Prone position as prevention of lung injury in comatose patients: a prospective, randomized, controlled study." Intensive care medicine 28.5 (2002): 564-569.
Guerin, Claude, et al. "Effects of systematic prone positioning in hypoxemic acute respiratory failure: a randomized controlled trial." Jama 292.19 (2004): 2379-2387.
Broccard, Alain F. "Prone position in ARDS: are we looking at a half-empty or half-full glass?." CHEST Journal 123.5 (2003): 1334-1336.
Cho, Young-Jae, et al. "411: The Efficacy and Safety of Prone Positional Ventilation in Acute Respiratory Distress Syndrome." Critical Care Medicine41.12 (2013): A99.
Messerole, Erica, et al. "The pragmatics of prone positioning." American journal of respiratory and critical care medicine 165.10 (2002): 1359-1363.
Chatte, Gerard, et al. "Prone position in mechanically ventilated patients with severe acute respiratory failure." American journal of respiratory and critical care medicine155.2 (1997): 473-478.