My buddies in NYC, my Italian stalwarts, and at my own beloved Janus General, we have had great success avoiding intubating using awake proning/repositioning. One of my former fellows, Dave Gordon, did a write up and then my protocol is at the end of the post. My friend Dave Cherkas calls this the pig roast (maybe save that moniker out of patient earshot) –Scott
Why to Do It?
Awake proning has been widely popularized in the era of Covid. This technique has been widely reported, gained popularity in the FOAM world, and was formally described in one protocol from China.1 Outside of Covid, several case studies have reported success with proning in awake patients. These case reports are heterogenous and include reports of patients with a variety of underlying etiologies of respiratory disorders and various approaches to respiratory support. Nonetheless, all cases describe generally short periods of intermittent proning that is well tolerated with either laboratory, radiographic, or clinical improvement.2-5 Why might this be the case?
Proning intubated patients has become a staple of ARDS care, and has been shown to improve mortality.6 This likely occurs via improved recruitment by altering shape matching of lung units to the chest wall, allowing recruitment of dorsal lung units, and improved V/Q matching.7 A similar phenomena occurs in non-intubated patients. Riera et al studied 20 healthy volunteers comparing end expiratory lung impedance (EELI) between room air and HFNC in the supine and prone positions. They found HFNC increased end expiratory lung impedance (EELI) when applied in the supine position by 1.22 units and by 0.87 units when applied in the prone position. The prone position however resulted in completely homogenous distribution of this increase, as opposed to the benefit being confined to the ventral lung when supine.8 Riedel et al had a similar finding when using non-invasive ventilation (NIV) of more uniform ventilation in the prone position compared to prone (though not statistically significant).9
Scaravilli et al evaluated 15 patients who underwent a total of 43 proning procedures.10 Their cohort consisted almost entirely of patients with pneumonia, but had a heterogeneous mix of approaches to Oxygen support. In 18 of the procedures patients were maintained on the same support approach in the prone position as they were on prior to pronation. Patients underwent a mean of 2 sessions of proning which lasted an average of 3 hours. Patients increases in their P:F ratios with proning (127 +/- 49 mmHg to 186 +/- 72), the largest increases were seen in the 10 patients on NIV (157 +/- 44 mmHg to 214 +/- 71 mmHg). Across the board the PaO2 and the HbO2 were significantly higher in the prone position, without changes in the pH or PaCO2.
Proning may not only improves oxygenation, but may have clinical relevance. Ding et al studied 20 patients who were initially on non-invasive support of at least PEEP of 5 and FiO2 of 0.5 or more, and had a PF <200.11 They excluded patients with respiratory acidosis, PaCO2 >50 mmHg, and who appeared uncomfortable. Using a stepwise approach patients were escalated from HFNC to HFNC + prone to NIV to NIV + prone in order to maintain SpO2 > 90%. They were able to decrease their intubation rate from a predicted rate of 75% to an actual rate of 45%. The success group increased P:F with every escalation up to NIV, but did not derive any additional benefit of NIV + prone. The group that failed to improve did not derive any such benefit from escalating levels of support. The success and failure groups were able to both undergo proning for similar periods of time, just under 2 hours. No patient who had a P:F <100 on NIV was able to avoid intubation, and the success group had higher initial SpO2 (95 vs 93), and PaO2 (125 mmHg vs 119 mmHg) . Clearly this study should be interpreted with caution as it is a small study, and the comparator was a predicted intubation rate.
How to Do It?–Dave's Take:
How can this be applied to our current patients? Consideration pf proning should be given for all patients that are grossly hemodynamically stable, that are able to adjust their own position, and can communicate on their own. Patients with a P:F of < 100 on NIV are probably not appropriate and this may delay an unavoidable intubation. Patients should prone, as tolerated for 2-4 hours/session, 2-4/day. Patients may receive light sedation in order to tolerate pronation., While the evidence is far from robust, this technique is currently being used and has both physiological and laboratory basis. More importantly it has a demonstrated anecdotal benefit to avoid intubation.
How to Do It?–Weingart's Take:
COVID Awake Repositioning/Proning Protocol (CARP)
Timed Position Changes
Q 2 hrs, ask patient to switch between the following positions,bed adjustments will be required between positions
- Left Lateral Recumbent
- Right Lateral Recumbent
- Sitting Upright 60-90 degrees
If patient is not CPAP Mask (because of high risk of disconnection), an additional position can be tried:
4. Lying Prone in bed (LIP may choose to Prone CPAP patients as well)
If these 4 positions are not raising the Oxygen Saturation, a 5th position can be tried:
5. Trendelenburg (Supine, Bed 30 degrees Head Down)
10-15 Minutes after each position change, check to make sure that Oxygen Saturation has not decreased. If it has, try another position.
Positions Changes to Counter Hypoxemia
If patient's has a significant drop in Oxygen saturation, follow these steps:
1. Ensure the source of the patient's Oxygen is still hooked up to the wall and is properly placed on the patient (this is a common cause of desaturation)
2. Ask patient to move to a different position as above
3. If after 10 minutes, the patient's saturations have not improved to prior levels, speak with LIP about escalation of oxygen modality vs. trial of additional positions
Explaining to the Patient
My Elmhurst Buddies (Bentley, Cherkas, Lane et al.) made this handout to give pts for home use, but I have been giving it to our ED patients as well to explain what the hell we are doing.
ICS Guideline Document
- Sun Q, Qiu H, Huang M, Yang Y. Lower mortality of COVID-19 by early recognition and intervention: experience from Jiangsu Province. Ann Intensive Care. 2020;10(1):33.
- Feltracco P, Serra E, Barbieri S, et al. Noninvasive high-frequency percussive ventilation in the prone position after lung transplantation. Transplantation proceedings. 2012;44(7):2016-2021.
- Feltracco P, Serra E, Barbieri S, et al. Non-invasive ventilation in prone position for refractory hypoxemia after bilateral lung transplantation. Clin Transplant. 2009;23(5):748-750.
- Valter C, Christensen AM, Tollund C, Schønemann NK. Response to the prone position in spontaneously breathing patients with hypoxemic respiratory failure. Acta Anaesthesiol Scand. 2003;47(4):416-418.
- Pérez-Nieto OR, Guerrero-Gutiérrez MA, Deloya-Tomas E, Ñamendys-Silva SA. Prone positioning combined with high-flow nasal cannula in severe noninfectious ARDS. Critical Care. 2020;24(1):114.
- Guérin C, Reignier J, Richard JC, et al. Prone positioning in severe acute respiratory distress syndrome. The New England journal of medicine. 2013;368(23):2159-2168.
- Gattinoni L, Taccone P, Carlesso E, Marini JJ. Prone position in acute respiratory distress syndrome. Rationale, indications, and limits. American journal of respiratory and critical care medicine. 2013;188(11):1286-1293.
- Riera J, Pérez P, Cortés J, Roca O, Masclans JR, Rello J. Effect of High-Flow Nasal Cannula and Body Position on End-Expiratory Lung Volume: A Cohort Study Using Electrical Impedance Tomography. Respiratory care. 2013;58(4):589-596.
- Riedel T, Richards T, Schibler A. The value of electrical impedance tomography in assessing the effect of body position and positive airway pressures on regional lung ventilation in spontaneously breathing subjects. Intensive care medicine. 2005;31(11):1522-1528.
- Scaravilli V, Grasselli G, Castagna L, et al. Prone positioning improves oxygenation in spontaneously breathing nonintubated patients with hypoxemic acute respiratory failure: A retrospective study. J Crit Care. 2015;30(6):1390-1394.
- Ding L, Wang L, Ma W, He H. Efficacy and safety of early prone positioning combined with HFNC or NIV in moderate to severe ARDS: a multi-center prospective cohort study. Critical care (London, England). 2020;24(1):28.
- EMCrit 278 – Labors of Trauma – Blunt Edition (Part 1) - July 24, 2020
- EMCrit 277 – COVID Pulmonary Physiology with Martin Tobin - July 9, 2020
- EMCrit 276 – The Rapid Code Status Conversation with Kei Ouchi - June 25, 2020