Prone ventilation, sometimes called prone positioning or proning, is a method of mechanical ventilation with the patient lying face-down (prone). It improves oxygenation in most patients with acute respiratory distress syndrome (ARDS) and reduces mortality.[1] The earliest trial investigating the benefits of prone ventilation occurred in 1976.[2] Since that time, many meta-analyses and one randomized control trial, the PROSEVA trial, have shown an increase in patients' survival with the more severe versions of ARDS.[3] There are many proposed mechanisms, but they are not fully delineated. The proposed utility of prone ventilation is that this position will improve lung mechanics, improve oxygenation, and increase survival. Although improved oxygenation has been shown in multiple studies, this position change's survival benefit is not as clear.[4][5][6] Similar to the slow adoption of low tidal volume ventilation utilized in ARDS, many believe that the investigation into the benefits of prone ventilation will likely be ongoing in the future.[7]

Physiologic effects

edit

The purpose of prone ventilation is to better facilitate lung mechanics to improve ventilation/perfusion ratio mismatches in ARDS.[8]

By redistributing pulmonary blood flow, oxygen levels can increase from low ventilated areas to higher ventilation.[4][5][6] The physiologic mechanism can be explained by a gravity-dependent increase in pleural pressure when supine compared to prone. In the prone position, the lungs' dorsal aspects have less pleural pressure, which alleviates forces trying to collapse the alveoli. When there is less pleural pressure, the alveoli can stay open and thus increase surface area for ventilation. Because there are more alveoli dorsally than ventrally, a prone position allows for more dorsal alveoli to stay open and thus increase the amount of ventilation available to be perfused.[8] Another benefit of prone ventilation may come from reduced VALI (Ventilator-associated lung injury). Proning and the redistribution of dependent fluid lead to more homogenous compliance of the lung and thus minimizes the barotrauma that usually occurs from more heterogeneous lungs and the repeated opening and closing of alveoli associated with it produces.[9] An observational study in 2007 found a reduction in IL-6, a marker of systemic inflammation, in the prone ventilation group compared to the supine ventilation. This reduction in inflammation was attributed to a decrease in barotrauma and a rapid decrease in the need for high FiO2, reducing the number of reactive oxygen species contributing to ongoing inflammation in the lung.[10]

Application and techniques

edit

Clinical applications

edit

The studies that have found survival benefit of prone ventilation derived benefit only from patients with severe ARDS defined as a Horowitz index of less than 200–150 mm Hg.[3][11] A meta-analysis published in 2017 suggested that patients only benefit from prone ventilation when they are in a prone position for longer than 12 hours a day.[12] A trained staff and the resources to move/monitor patients is important

COVID-19 pandemic

edit

During the 2020 COVID-19 pandemic, awake high flow nasal cannula in the prone position, awake proning, was utilized to keep patients from being intubated.[13] A retrospective analysis showed that the number needed to treat and keep people off the ventilator was 6.[14] This significantly reduced amount of required ventilators allowing for the use of ventilators in those in critical condition. The Society of Critical Care Medicine gave prone ventilation a weak recommendation in The Surviving Sepsis Campaign COVID-19 panel.[15] The panel cited the few studies that showed morality benefit from prone ventilation in ARDS and that this was a low-cost intervention; however, they cautioned the use due to the necessity of needing competent staff and complications that can occur if done incorrectly.

Considerations in the pediatric population

edit

Special precautions must be in place for prone ventilation in children because of their risk of sudden infant death syndrome (SIDS).[16] An updated Cochrane meta-analysis (2022) found low certainty evidence of benefit in oxygen saturation with prone positioning of mechanically ventilated preterm infants with ARDS but due to the increased risk of SIDS hospitalized infants and children should only be placed in this position with cardiorespiratory monitoring.[17]

Contraindications

edit
  1. Hemodynamic instability.
  2. unstable fractures or polytrauma patients with unstable fracture spine
  3. tracheostomy
  4. chest tubes
  5. obesity
  6. pregnancy
  7. intracranial pressure raised
  8. cardiac surgery
  9. massive hemoptysis
  10. aspiration pneumonia

Complications

edit

There are many complications of proning patients. Most of the complications occur because of the intrinsic position and the effect of gravity on body parts unaccustomed to its effects. Some complications have occurred because of the logistics of increased time that staff members need to monitor and help patients in this disabling position.[18] Complications include increased endotracheal tube displacement and even accidental extubation, loss of vascular lines, pressure sores, brachial plexopathy, enteral feeding intolerance, facial edema, and injury.[19][20][21][22][23] New data from patients with COVID-19 found that prone ventilation was associated with a deterioration in glycaemic control and increased insulin requirements,[24] although the mechanism of this remains obscure.

References

edit
  1. ^ Sud S, Friedrich JO, Adhikari NK, Taccone P, Mancebo J, Polli F, et al. (8 July 2014). "Effect of prone positioning during mechanical ventilation on mortality among patients with acute respiratory distress syndrome: a systematic review and meta-analysis". Canadian Medical Association Journal. 186 (10): E381–E390. doi:10.1503/cmaj.140081. PMC 4081236. PMID 24863923.
  2. ^ Douglas W, Rehder K, Beynen F, Sessler A, Marsh HM (1976). "Improved Oxygenation in Patients with Acute Respiratory Failure: The Prone Position". American Review of Respiratory Disease. 115 (4).
  3. ^ a b Guérin C, Reignier J, Richard J, Beuret P, Gacouin A, Boulain T, et al. (6 June 2013). "Prone Positioning in Severe Acute Respiratory Distress Syndrome". New England Journal of Medicine. 368 (23): 2159–2168. doi:10.1056/NEJMoa1214103. PMID 23688302. S2CID 2763593.
  4. ^ a b Gattinoni L, Tognoni G, Pesenti A, Taccone P, Mascheroni D, Labarta V, et al. (23 August 2001). "Effect of Prone Positioning on the Survival of Patients with Acute Respiratory Failure". New England Journal of Medicine. 345 (8): 568–573. doi:10.1056/NEJMoa010043. PMID 11529210.
  5. ^ a b Voggenreiter G, Aufmkolk M, Stiletto RJ, Baacke MG, Waydhas C, Ose C, et al. (August 2005). "Prone Positioning Improves Oxygenation in Post-traumatic Lung Injury--A Prospective Randomized Trial". The Journal of Trauma: Injury, Infection, and Critical Care. 59 (2): 333–343. doi:10.1097/01.ta.0000179952.95921.49. PMID 16294072.
  6. ^ a b Mancebo J, Fernández R, Blanch L, Rialp G, Gordo F, Ferrer M, et al. (June 2006). "A Multicenter Trial of Prolonged Prone Ventilation in Severe Acute Respiratory Distress Syndrome". American Journal of Respiratory and Critical Care Medicine. 173 (11): 1233–1239. doi:10.1164/rccm.200503-353OC. PMID 16556697.
  7. ^ Broccard A (May 2001). "Prone Position in ARDS Are We Looking at a Half-Empty or Half-Full Glass?". Chest. 123 (5): 1334–6. doi:10.1378/chest.123.5.1334. PMID 12740242.
  8. ^ a b Tobin A, Kelly W (April 1999). "Prone Ventilation—It's Time". Anaesthesia and Intensive Care. 27 (2): 194–201. doi:10.1177/0310057X9902700213. PMID 10212720. S2CID 28020263.
  9. ^ Scholten EL, Beitler JR, Prisk GK, Malhotra A (January 2017). "Treatment of ARDS With Prone Positioning". Chest. 151 (1): 215–224. doi:10.1016/j.chest.2016.06.032. PMC 6026253. PMID 27400909.
  10. ^ Chan M, Hsu JY, Liu H, Lee Y, Pong S, Chang L, et al. (2007). "Effects of Prone Position on Inflammatory Markers in Patients with ARDS Due to Community-acquired Pneumonia". J Formos Medical Association. 106 (9): 708–16. doi:10.1016/S0929-6646(08)60032-7. PMID 17908660.
  11. ^ Sud S, Friedrich JO, Taccone P, Polli F, Adhikari NK, Latini R, et al. (April 2010). "Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis". Intensive Care Medicine. 36 (4): 585–599. doi:10.1007/s00134-009-1748-1. PMID 20130832. S2CID 2002245.
  12. ^ Munshi L, Del Sorbo L, Adhikari N, Hodgson C, Wunsch H, Meade M, et al. (August 15, 2017). "Prone Position for Acute Respiratory Distress Syndrome. A Systematic Review and Meta-Analysis". Annals of the American Thoracic Society. 14 (4): S280–S288. doi:10.1513/AnnalsATS.201704-343OT. hdl:2434/531962. PMID 29068269. S2CID 43367332.
  13. ^ Anand S, Baishya M, Singh A, Khanna P (September 2020). "Effect of awake prone positioning in COVID-19 patients- A systematic review". Trends in Anaesthesia and Critical Care. 36: 17–22. doi:10.1016/j.tacc.2020.09.008. PMC 7521914. S2CID 221980796.
  14. ^ Jagen N, Morrow L, Walters R, Klein L, Wallen T, Chung J, et al. (2020). "The POSITIONED Study: Prone Positioning in Nonventilated Coronavirus Disease 2019 Patients—A Retrospective Analysis". Critical Care Explorations. 2 (10): e0229. doi:10.1097/CCE.0000000000000229. PMC 7531752. PMID 33063033.
  15. ^ Alhazzani W, Møller MH, Arabi YM, Loeb M, Gong MN, Fan E, et al. (June 2020). "Surviving Sepsis Campaign: Guidelines on the Management of Critically Ill Adults with Coronavirus Disease 2019 (COVID-19)". Critical Care Medicine. 48 (6): e440–e469. doi:10.1097/CCM.0000000000004363. PMC 7176264. PMID 32224769.
  16. ^ Ponsonby A, Dwyer T, Gibbons L, Cochrane J, Wang Y (August 5, 1993). "Factors Potentiating The Risk Of Sudden Infant Death Syndrome Associated With The Prone Position". The New England Journal of Medicine. 329 (6): 377–82. doi:10.1056/NEJM199308053290601. PMID 8326970.
  17. ^ Bhandari, Abhishta P.; Nnate, Daniel A.; Vasanthan, Lenny; Konstantinidis, Menelaos; Thompson, Jacqueline (2022-06-06). "Positioning for acute respiratory distress in hospitalised infants and children". The Cochrane Database of Systematic Reviews. 2022 (6): CD003645. doi:10.1002/14651858.CD003645.pub4. ISSN 1469-493X. PMC 9169533. PMID 35661343.
  18. ^ Messerole E, Peine P, Wittkopp S, Marini JJ, Albert RK (2002-05-15). "The Pragmatics of Prone Positioning". American Journal of Respiratory and Critical Care Medicine. 165 (10): 1359–1363. doi:10.1164/rccm.2107005. ISSN 1073-449X. PMID 12016096.
  19. ^ Bloomfield R, Noble DW, Sudlow A (2015-11-13). Cochrane Emergency and Critical Care Group (ed.). "Prone position for acute respiratory failure in adults". Cochrane Database of Systematic Reviews. 2020 (11): CD008095. doi:10.1002/14651858.CD008095.pub2. PMC 6464920. PMID 26561745.
  20. ^ Kallet RH (2015-11-01). "A Comprehensive Review of Prone Position in ARDS". Respiratory Care. 60 (11): 1660–1687. doi:10.4187/respcare.04271. ISSN 0020-1324. PMID 2649359. S2CID 31296099.
  21. ^ Peko L, Barakat-Johnson M, Gefen A (2020-07-03). "Protecting prone positioned patients from facial pressure ulcers using prophylactic dressings: A timely biomechanical analysis in the context of the COVID‐19 pandemic". International Wound Journal. 17 (6): 1595–1606. doi:10.1111/iwj.13435. ISSN 1742-4801. PMC 7361768. PMID 32618418.
  22. ^ Girard R, Baboi L, Ayzac L, Richard J, Guérin C, Proseva trial group (2014). "The impact of patient positioning on pressure ulcers in patients with severe ARDS: results from a multicentre randomised controlled trial on prone positioning". Intensive Care Medicine. 40 (3): 397–403. doi:10.1007/s00134-013-3188-1. ISSN 0342-4642. PMID 24352484. S2CID 4561567.
  23. ^ Simpson AI, Vaghela KR, Brown H, Adams K, Sinisi M, Fox M, et al. (2020). "Reducing the Risk and Impact of Brachial Plexus Injury Sustained From Prone Positioning—A Clinical Commentary". Journal of Intensive Care Medicine. 35 (12): 1576–1582. doi:10.1177/0885066620954787. ISSN 0885-0666. PMID 32959717. S2CID 221845043.
  24. ^ Griffiths, Harry; Cardwell, Amy; Richardson, Max; Barne, Meg; Petrisor, Bogdan; Usman, Ammara; Heales, Laura; Latorre, Julia Calvo; Bansiya, Vishakha; Mahroof, Razeen; Szakmany, Tamas; Martin, Daniel; Rostron, Anthony; Morris, Andrew Conway; Lockhart, Sam (2024-11-12). "Prone positioning is associated with increased insulin requirements in mechanically ventilated patients with COVID-19". Scientific Reports. 14 (1): 27668. doi:10.1038/s41598-024-78904-3. ISSN 2045-2322. PMC 11557589.