Patients on mechanical ventilation are known to halve their mortality by being administered proning positions (lying on your stomach, on your side, sitting up or walking about - but not lying on your back {supine position} or very little).
But not many studies had been done for awake non-intubated patients in regard to proning, whether done by self or in hospital settings.
However such studies have gathered pace during the Covid-19 pandemic. 18 such studies are summarized below.
In one study in Nebraska, USA, after patients were educated on the benefits of awake self-proning, compliance was voluntary. The risk of intubation was lower in proned patients after adjusting for disease severity. No prone patient died compared with 24.6% of patients who were not prone.
Conclusions: Awake self-proning was associated with lower mortality and intubation rates in coronavirus disease 2019-infected patients. Prone positioning appears to be a safe and inexpensive strategy to improve outcomes and spare limited resources.
As the pandemic progresses, scarce resources (e.g., ICU beds and mechanical ventilators) may become a rate-limiting factor in the care for these patients. Therefore, therapies to prevent the need for intubation and mechanical ventilation are desperately needed.
We hypothesized that patients with COVID-19 and respiratory distress, not yet intubated but at high risk for intubation, might benefit from prone positioning.
Ten adult patients at an academic medical center with confirmed positive PCR testing results, with rapidly increasing oxygen requirements necessitating ICU admission but not yet requiring intubation, were determined to be appropriate clinical candidates for proning.
Patients were asked to alternate every 2 hours between a prone and supine (lying on your back) position during the day and sleep in a prone position at night, as tolerated.
Oxygenation rapidly improved after prone positioning, and at 1 hour after assuming a prone position, median oxygen saturations had increased from 94% to 98%.
After prone positioning, work of breathing had improved, as evidenced by a reduced median respiratory rate from 31 to 22 breaths/min.
Eight of the 10 patients did not require intubation (being put on mechanical ventilator).
At 28 days of follow-up, all patients had been discharged from the hospital to their homes.
https://www.atsjournals.org/doi/full/10.1164/rccm.202004-1331LE
We enrolled 56 patients for a study in Italy. Prone positioning was feasible (i.e., maintained for at least 3 h) in 47 patients. It was effective in rapidly ameliorating blood oxygenation in awake patients with COVID-19-related pneumonia requiring oxygen supplementation. The effect was maintained after resupination in half of the patients.
https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30268-X/fulltext
Among 29 eligible patients in New York, 25 had at least 1 awake session of the prone position lasting longer than 1 hour; 4 refused the prone position and were intubated immediately.
We found that the use of the prone position for awake, spontaneously breathing patients with COVID-19 severe hypoxemic respiratory failure was associated with improved oxygenation. In addition, patients with an Spo2 of 95% or greater after 1 hour of the prone position was associated with a lower rate of intubation.
https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2767575
Many critical hypoxemic patients were treated in wards in a Paris hospital due to lack of intensive care units bed availability.
Twenty-seven patients were included in a study - confirmed Covid-19 hypoxemic patients who benefited from at least one prone position were included. Eighteen patients were responders (defined as an improvement of SpO2/FiO2 of more than 50) during the first posture and have a shorter length of hospital stay than non-responder patients.
Our study found that prone position in wards improved alveolar exchange during posture and is well tolerated. However, oxygenation improvement did not seem to persist when the position was stopped.
Elharrar et al. have yet ascertained that only 25% were responders (had sustained improvements) to prone position.
On the other hand, Sartini et al. found that 12 of 15 patients had persistent oxygenation improvement after the posture’s end.
https://link.springer.com/article/10.1007/s11845-020-02479-x
In a London hospital, forty eight of 138 patients managed outside of a critical care unit with facemask oxygen, high flow nasal oxygen or continuous positive airway pressure, underwent prone positions.
Prone position was associated with significant improvement in oxygenation, lower ICU admission, tracheal intubation, and shorter ICU length of stay. Lack of response to PP may be an indicator of treatment failure, requiring early escalation.
https://journals.sagepub.com/doi/full/10.1177/1751143721996542
The main outcome reported was that prone positioning improved P/F ratio from 17.9 to 28.2 kPa after 81 average min across 36 subjects, of which 26 had a response of ≥20%. Results from 32 subjects indicate that the response persisted on return to supine.
In the current report, death or progression to extracorporeal membrane oxygenation was more frequent in those displaying a diminished response to further prone manoeuvres.
https://bjanaesthesia.org/article/S0007-0912(21)00100-8/fulltext
Six relevant studies, including an observational cohort study with 50 patients, and five case series with 53 patients were identified. All studies included, noted improved clinical symptoms after proning. In Elharrar et al., Caputo et al., and Paul et al., improved oxygen saturation of 20%, 10%, and 6% respectively from the baseline is observed.
Additionally, in Paul et al. study, FiO2 requirements were titrated from 0.8 to 0.4 within one hour of proning. In the studies of Sartini et al. and Sztajnbok et al. PaO2: FiO2 was noticed to improve.
In patients who underwent awake proning, it was noticed that only 13/50 (26%) in Caputo et al., 1/15 (6.7%) in Sartini et al., and 5/ 24 (20.8%) in Elharrar et al. studies needed mechanical ventilation.
Similar results of reduced need for mechanical ventilation and improved oxygenation were found in Ng et al. study.
https://journals.lww.com/ccmjournal/Fulltext/2021/01001/262__Awake_Self_Prone_Positioning_Outcomes_in.230.aspx
A total of 45 subjects were included (30 cases and 15 controls). The median duration of prone positions achieved was 7.5 h on the 1st day.
The need for mechanical ventilation was higher in the control group (5/15; 33.3%) versus prone group (2/30; 6.7%).
At 30 min, there was a statistically significant improvement in the mean ROX index of cases compared with that of the controls.
No significant adverse effects related to intervention were noted.
https://www.lungindia.com/article.asp?issn=0970-2113;year=2021;volume=38;issue=7;spage=6;epage=10;aulast=Sryma
An area of current study is the use of proning in awake, spontaneously breathing COVID-19 patients with respiratory failure outside of the ICU in an attempt to prevent escalation to intubation and mechanical ventilation.
In one study, 50 patients with mild to moderate ARDS from COVID-19 requiring oxygen therapy outside of the ICU were treated with a protocol of prone positioning three times per day for 30-60 minutes alternating with supine positioning.
Prone positioning was associated with significant increases in oxygenation during proning and after returning to the supine position as well.
At 45-day follow-up, there were two deaths out of the 50 study subjects, seven patients required ICU admission, and 41 patients had been discharged from the hospital.
https://www.reliasmedia.com/articles/147467-prone-positioning-in-acute-respiratory-distress-syndrome
Awake proning is a practice that was adopted early in the pandemic as a means to avoid, or at least delay, endotracheal intubation to lessen the burden of ICU care.
2994 patients were included in a systematic review and meta-analysis of observational trials comparing in-hospital intubation and mortality rates in patients treated with awake proning vs standard care.
27% of the Awake Prone needed intubation eventually, vs. 30% in Standard Care.
Awake proning was associated with significant improvement of oxygenation parameters.
Some studies showed this was sustained after patients returning to supine position. One study each showed that 50% of patients retained improved oxygenation after returning to supine position; and the other study said improvement was lost after returning to supine position.
https://rebelem.com/covid-19-awake-proning-all-hype/
A prospective study of 30 COVID patients admitted in our Hospital critical care isolation. Awake prone positioning and non-invasive ventilation showed marked improvement in SaO2 and PaO2 in COVID-19 patients with improvement in clinical symptoms with reduced rate of intubation with superiority of non invasive ventilation.
https://www.tandfonline.com/doi/full/10.1080/11101849.2021.1889944
In the absence of effective targeted therapies for COVID-19, optimisation of supportive care is essential. Lung injury with features of acute respiratory distress syndrome (ARDS) appears to be the principal characteristic of severe acute respiratory syndrome coronavirus 2 infection. Recent guidance by the UK Intensive Care Society advocates awake prone positioning to become standard of care for suspected or confirmed COVID-19.
Valter et al applied prone positioning to four patients with indications for mechanical ventilation and found rapid improvements in PaO2—all patients avoided mechanical ventilation and tolerated prone positioning well.
In an observational study of 15 patients receiving non-invasive respiratory support for acute hypoxaemic respiratory failure, repeated prone positioning led to transient but substantial improvements in oxygenation.
In a prospective observational study of 20 patients receiving non-invasive ventilation for moderate-to-severe ARDS, PaO2/FiO2 ratio increased by 25–35 mm Hg following awake prone positioning; but 78% of participants with severe ARDS eventually required mechanical ventilation (MV), and therefore awake prone positioning should not delay the use of MV when indicated.
In summary, awake prone positioning appears to be safe and may slow the respiratory deterioration in select patients with COVID-19, who require oxygen supplementation or NIV/CPAP. This in turn may reduce demand for MV, easing the strain placed on intensive care services around the world.
https://thorax.bmj.com/content/75/10/833
27 patients with confirmed COVID-19 pneumonia admitted to a Switzerland Hospital were included in the study. 10 patients were randomised to self-prone positioning and 17 to usual care.
https://jamanetwork.com/journals/jama/fullarticle/2766292
27 spontaneously breathing adults with COVID‐19 admitted to Austin Hospital in Australia were selected for a study.
Twenty (74%) patients received proning at least once, six (22%) never received proning despite clinical indication (e.g. refused) and for one patient proning was documented but no data were available.
For the patients who received proning, the median number of treatments per patient was three, and their duration was 105 minutes.
In summary, in spontaneously breathing patients with COVID‐19, on an analysis of close to 100 treatments, we found no evidence of reproducible response to proning and no relationship between the effect of proning on first treatment with subsequent treatments.
https://onlinelibrary.wiley.com/doi/full/10.1111/resp.14008
Infection with SARS-CoV-2 can result in Coronavirus Disease–19 (COVID-19). While the majority of patients are asymptomatic or have mild disease, approximately 14% develop more severe disease including hypoxemic respiratory failure and/or Acute Respiratory Distress Syndrome (ARDS). A synthesis of 35 studies (414 patients) was carried out, that examined the use of awake prone positioning for non-intubated patients with hypoxemic respiratory failure.
The duration of prone positioning sessions varied from <1 h to >18 h and was not reported in three studies. All studies demonstrated improvements in oxygenation while patients were in the prone position except one. When reported, improvements in oxygenation were generally not sustained after returning to the supine position except in two studies in which patients were receiving NIV (Non-Invasive Ventilation assists breathing by supplying a mixture of air and oxygen using positive pressure to help the patient to take deeper breaths). One hundred twenty-one patients (29%) of the 414 patients required invasive mechanical ventilation. Adverse events were variably reported and included 42 deaths among the 414 patients (10.1% of all patients).
In summary, although awake prone positioning may be a promising therapy for patients with hypoxemic respiratory failure (including those with COVID-19), the supporting evidence is limited to case reports and cohort studies.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7450241/
60 patients diagnosed with acute hypoxic respiratory failure secondary to COVID −19 pneumonia requiring 4 or more litres of oxygen to maintain a saturation of ≥ 92% were recruited in this study.
Thirty patients each were randomised to either standard care or awake prone group. Patients randomised to the standard care were allowed to change their position as per comfort and patients randomized to the prone group were encouraged to self-prone for at least 6 hours a day.
In the prone group, 43% (13 out of 30) of patients were able to self-prone for 6 or more hours a day. The median maximum prone duration per session was 2 hours. In the supine group, 47% (14 out of 30) were completely supine and 53% spent some hours in the prone position, but none exceeded 6 hours. There was no significant difference in any of the secondary outcomes between the two groups and there were no adverse events.
https://www.medrxiv.org/content/10.1101/2021.03.13.21253499v1
