COVID-19: Awake Proning

Background: Awake proning, or having patients lie on their stomachs, can help oxygenation by helping to recruit posterior portions of the lungs and by helping with perfusion to oxygenated lung segments. The literature around proning centers on intubated patients with adult respiratory distress syndrome in the ICU. However, there are increasing recommendations from front line clinicians and experts about the benefits of proning hypoxemic COVID19 patients who are awake in an effort to improve oxygenation and stave off intubation. While there may be physiologic reasoning, anecdotal experience and application of data from intubated patients, there is an absence of data specifically on COVID19 patients and proning. Fortunately, we now have some literature to look at:

Article: Caputo ND, Strayer RJ, Levitan R. Early self-proning in awake, non-intubated patients in the emergency department: a single ED’s experience during the COVID-19 Pandemic. Acad Emerg Med Published on-line April 22, 2020. [Epub Ahead of Print]

Clinical Question: Does awake self-proning improve oxygen saturation?

Population: Convenience sample of adult patients (> 18 years of age) who presented to the ED with hypoxia (SpO2 < 90%) who did not improve with supplemental oxygen and were capable of self-proning. All patients included had SARS-CoV-2 confirmed by nasal/oropharyngeal swab by RT-PCR

Study Protocol:

• SpO2 was measured at presentation and supplemental O2 (nasal cannula (NC) or non-rebreather (NRB)) was applied
• SpO2 measured after application of NC or NRB
• SpO2 measured after awake-proning for 5 minutes

Outcomes:

• Primary: change in O2 saturation from presentation to post-application of supplemental O2 and after 5 minutes of proning without changing the inspired oxygen fraction.
• Secondary: Rate of proned patients requiring intubation within 24 hours of ED presentation
• Failed Proning: Persistent SpO2 < 90% in the setting of unresolved or worsening tachypnea with accessory muscle use, altered mental status or hypercarbia on blood gas.

Design: Prospective observational study

Excluded:

• DNR/DNI
• Cardiac arrest
• Receiving non-invasive ventilation
• Intubated pre-hospital

Results:

• 50 patients enrolled
  • Median Age = 59
  • EMS arrival: 20%
• Median SpO2 at triage = 80%

• Secondary Outcome (failed proning): n = 13 (26%)
  • Intubated within 30 minutes of proning: n = 4 (8%)
  • Intubated 30-60 minutes after proning: n = 3 (6%)
  • Intubated > 60 minutes after proning: n = 6 (12%)
  • Intubated > 24 hours after presentation: n = 5 (10%)
  • Overall, 36% of patients required intubation over the first 3 days of hospitalization

Strengths:

• First study looking at a clinically important question in the management of COVID19 patients
• Patients included were at least moderately ill on presentation based on presenting SpO2
• Evaluates a low cost intervention that can safely improve oxygenation without the need for additional resources

Limitations:

• This was a pilot study and not a trial. There was no randomization to a control group to use as a comparison. It’s unclear how much proning helped or, potentially, hurt patients.
• Other aspects of patient care were not standardized but instead were left up to the clinicians taking care of the patients.
• The study focused on a disease oriented outcome (SpO2)
• Single center which had the ability to monitor patients closely may not extrapolate to facilities where staffing is not adequate to monitor patients
• Convenience sample of patients which may bias results (in the methods section, states consecutive but confirmed with Dr. Nick Caputo that, in fact, it was a convenience sample)

Discussion:

• While this is not robust data on awake proning, it gives clinicians a sense of novel modalities for increasing oxygenation in COVID19 patients
• Neither CPAP nor HFNC was applied to patients prior to proning. These modalities may have increased O2 saturations on their own and, with or without proning, may have staved off more intubations. Future studies incorporating CPAP/HFNC will be important
• Ultimately, 36% of patients in this cohort were intubated reflecting the severity of disease either on presentation or that developed during hospitalization
• Patients with COVID-19 may desaturate precipitously and dangerously when disconnected from their oxygen source.  Patients with higher oxygen requirements must be monitored vigilantly and frequently while being careful to not disconnect oxygen in the process of proning

Author Conclusions: Awake early self-proning in the emergency department demonstrated improved oxygen saturation in our COVID-19 positive patients. Further studies are needed to support causality and determine the effect of proning on disease severity and mortality.

Our Conclusions: We agree with the authors measured conclusions. Proning is a promising approach to patient management but, we need more data to truly understand both the benefits and potential harms. Application of a proning strategy in your department requires careful patient selection as well as close monitoring and reassessment.

Proning Protocol (Adapted from Lincoln and St. Joseph’s Emergency Department)

Eligible patients for proning protocol:

1. 1. Grossly hemodynamically stable
   2. Able to adjust their own position
   3. Can communicate on their own (ie call for help, use call button to alert staff)
   4. Have the following O2 requirements:
      1. Nasal Cannula O2
      2. Venti Mask
      3. Non-Rebreather Mask with or without Nasal Cannula
      4. High-Flow Nasal Cannula

Positioning Basics:

• In addition to prone position encourage rotation between sitting up, lying on the left or right side and full prone
• Encourage patients to avoid lying on back
• Encourage patients to spend as much time in full prone position as they tolerate
• Handout (included below) can be given to patient so that they will be positioning themselves

Proning Protocol

• O2, cardiac and blood pressure monitoring must all be continued
• Patients should have call button within reach
• Patients under proning protocol should be moved closer to nursing/doctor stations (direct line of sight)
• Initiating Proning:
  • RN and physician at bedside to help patient if needed
  • Appropriate patients will have their vitals and SpO2 documented prior to proning and then again after 10 minutes
  • A second follow up with the patient to monitor patient position and clinical response will occur approximately 20 minutes after the initial position change.
• Once patient comfort in position established, team member should check on patient every 1-2 hours to assess clinical status

Patients with larger abdominal girth may not tolerate prone position on standard hospital mattresses. We have obtained these mattresses from https://www.prone2help.org/

Swami’s Approach:

• Evaluate hypoxemic patient for “comfortable hypoxia” vs hyperacute/crashing or high risk for rapid deterioration
• Place appropriate hypoxemic patient on NC, NRB, NC + NRB or HFNC
• Watch patient for 5-10 minutes while setting up stretcher and monitor for proning (or retrieving special mattress for proning if you have them)
• If pt saturation improving on supplemental O2 and HD stable, ask patient to self-prone
• If unsure about diagnosis (ie you are not working in a 100% COVID setting) perform lung US while patient proned to aid in confirming diagnosis
• Re-evaluate patient at q10-15 minutes for next hour
• Obtain CXR if needed

Resources:

• Self Proning Instruction PDF Sheet: Self-Prone Positioning_English and  Spanish
• REBEL EM: COVID-19 The Novel Coronavirus 2019
• EM:RAP: COVID-19 Response
• Resus Nurse: Proning as Part of Your COVID-19 Bundle

For More on This Topic Checkout:

• FOAMCast: COVID-19 – Self Proning Oxygenation
• emDocs: COVID-19 – Awake Repositioning/Proning
• PulmCrit: Awake Proning for COVID-19

Post Peer Reviewed By: Salim R. Rezaie, MD (Twitter:@srrezaie)