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Lying facedown on your stomach is described as being in the prone position. This position is often used to help patients who are experiencing respiratory distress.
Since the coronavirus pandemic began, doctors have been using this position to help patients with severe COVID-19. It can sometimes help patients avoid the need for a ventilator. It’s also been shown to improve survival rates for patients on ventilators.
Prone position is the medical term for lying flat on your stomach. Lying flat on your back is referred to as the supine position.
Prone position is used in medical settings to help patients with certain conditions and symptoms get relief. For example, people in respiratory distress are often carefully placed in prone position by medical staff. Turning someone so that they’re in prone position is called proning.
COVID-19 affects your respiratory system. It causes inflammation and swelling in your throat and lungs.
In mild or moderate cases of COVID-19, the inflammation leads to symptoms such as dry cough and sore throat. In severe cases, the inflammation causes fluid to build up in your lungs. The fluid in your lungs makes it extremely difficult to breathe. This is called acute respiratory distress syndrome (ARDS).
While more research needs to be conducted, doctors have found that the prone position helps patients with severe COVID-19.
Proning allows the back of your lungs to expand fully. It can also help you cough up more of the fluid in your lungs and can improve the way oxygen travels through your body. This can lead to better breathing overall.
Patients who are put in the prone position are carefully monitored. Medical staff will place them in the prone position for a set number of hours before transitioning them back to the supine position for a few hours.
The process might be repeated over the course of several days if the person is breathing better and can tolerate the treatment. In some cases, this has helped people avoid being intubated and placed on ventilators in the ICU.
The prone position has also been successfully used on COVID-19 patients who were using ventilators. Careful use of the prone position has been shown to improve the survival rate for ventilated patients.
Much of the research that has been done isn’t specific to COVID-19, but doctors are able to apply techniques, such as proning, that have been proven to help patients experiencing ARDS caused by other conditions.
The prone position is used for ARDS caused by any condition. Other conditions that might lead to ARDS include:
- pneumonia
- pancreatitis
- sepsis
ARDS can also be caused by serious accidents and injuries such as:
- breathing in harmful substances
- drowning
- severe injuries to your head, chest, or other body parts
Not all patients experiencing ARDS are good candidates for the prone position. People with burns, wounds, fractures, or spinal instability might not be able to tolerate the prone position. Proning is also not recommended for people who’ve had tracheal surgery or are in later stages of pregnancy.
The prone position is used during surgeries that require access to the back of your body. Some common examples include:
Medical staff will assist you in slowly and carefully laying on your stomach if you need to be in the prone position for a surgery. You’ll generally receive anesthesia first and will be hooked up to any needed monitors, IVs, or other medical equipment before being placed in the prone position. There will be supportive cushioning to prevent injury to your face, breasts, and pelvic region.
Proning is the medical term for carefully placing a patient facedown. It’s often used to improve breathing in patients experiencing respiratory distress, including patients with severe cases of COVID-19.
The prone position can sometimes prevent the need for a ventilator. It can also help patients who have been placed on a ventilator and has been shown to improve the odds of survival.
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| Antunes (2016) [45] | Mini Wright® (Clement Clarke International Ltd. Edinburgh Way Harlow, Essex, UK) peak flow meter portable device with a disposable mouthpiece | Random position order | 1 min | Moderate |
| Badr (2002) [46] | Pressure manometer, vitalograph (Compact, Vitalograph Ltd., Buckingham, UK) | Random position order Random test order (PEF and PEmax) Subjects instructed on equipment use, practiced before test | 5 min | Low |
| Baydur (2001) [35] | Spirometry | Random position order | N/A | Moderate |
| Ben-Dov (2009) [17] | Spirometry | N/A | N/A | Moderate |
| Benedik (2009) [52] | Helium dilution | First position always sitting | 5 min | Moderate |
| Ceridon (2011) [18] | Spirometry, DLCO measured by rebreathe technique | N/A | 30 min supine position prior to test Time prior to seated measurement not mentioned | Moderate |
| Chang (2005) [53] | Spirometry, FRC measured using helium dilution | First position always supine | 5 min | Moderate |
| Costa (2015) [54] | Mouth pressure meter | Random position order | 10 min | Moderate |
| De (2012) [29] | Spirometry | First position was always sitting | N/A | Moderate |
| Elkins (2005) [47] | Pressure manometer, spirometry - mass flow sensor | Random position and test order (PEF, PEmax) Subjects instructed on equipment use, practiced before test | 5 min | Low |
| Faggiano (1998) [58] | Single breath technique using a Medical Graphics PF/DX module (Medical Graphics St. Paul, Minn, USA) for determining DLCO | Random position order | 10 min | Moderate |
| Ganapathi (2015) [19] | Digital spirometry (BIOPAC System Inc. Goleta, California, USA) | N/A | N/A | Moderate |
| Gianinis (2013) [48] | Portable peak expiratory flow-device | Random position order | N/A | Moderate |
| Kim (2012) [36] | Spirometry | N/A | N/A | Moderate |
| Linn (2000) [33] | Spirometry | Random position order | N/A | Moderate |
| Manning (1999) [20] | Spirometry, single breath for determining DLCO | Two protocols (Session A & B). First chosen at random then alternated for successive subjects. First position always sitting. | 15 min | Moderate |
| McCoy (2010) [49] | Peak flow meter | Random position order. Subjects instructed on equipment use, practiced before test | N/A | Moderate |
| Melam (2014) [30] | Spirometry (Excel/PC-based pulmonary function tests) | Random position order | N/A | Moderate |
| Meysman (1998) [3] | Spirometry, peak flow meter | Random position order | 10 min | Moderate |
| Miccinilli (2016) [40] | Spirometry | N/A | N/A | Moderate |
| Mohammed (2017) [31] | Spirometry | Order of positions always standing, sitting, supine, lateral decubitus | N/A | Moderate |
| Myint (2017) [42] | Spirometry | Order of positions was standing, sitting, supine | N/A | Moderate |
| Naitoh (2014) [39] | Spirometry, breath dynamometer (Chest Co. Ltd) | First position always sitting | N/A | Moderate |
| Ogiwara (2002) [55] | Vitalpower KH-101 (Chest M.I. Inc., Japan) | Random position order | 10 min | Moderate |
| Ottaviano (2016) [50] | Peak flow meter | Random position order | N/A | Moderate |
| Palermo (2005) [21] | Spirometry, DLCO measured by a single breath technique | Random position order | 15 min | Moderate |
| Park (2010) [34] | Spirometry | N/A | N/A | Moderate |
| Patel (2015) [22] | Spirometry | First position always sitting | N/A | Moderate |
| Peces-Barba (2004) [56] | Single breath technique, rebreathing technique for determining DLCO | N/A | 3–5 min | Moderate |
| Poussel (2014) [38] | Spirometry | Random position order | N/A | Moderate |
| Razi (2007) [32] | Spirometry | Alternately sitting, standing | N/A 15 min between positions | Moderate |
| Roychowdhury (2011) [44] | Spirometry | N/A | N/A 5 min rest between positions | Moderate |
| Saxena (2006) [23] | Spirometry | N/A | N/A | Moderate |
| Sebbane (2015) [41] | Spirometry, multiple breath helium dilution method | First position always sitting | N/A | Moderate |
| Stewart (2000) [24] | Single breath method for determining DLCO | N/A, 72 h between positions | 15 min | Moderate |
| Terson de Paleville (2014) [37] | Spirometry, MP45–36-350 differential pressure transducer Validyne Engineering, (Northridge Ca, USA) | First position always sitting | 30 min | Moderate |
| Terzano (2009) [57] | Single breath DLCO technique | Random position order | At least 15 min | Moderate |
| Tsubaki (2009) [28] | Micro RPM 01 (Micro Medical, UK), spirometry | Random position order | N/A | Moderate |
| Varrato (2001) [25] | Spirometry | N/A | N/A | Moderate |
| Vilke (2000) [26] | Spirometry | First position always supine/prone | N/A | Moderate |
| Wallace (2013) [51] | Peak flow meter | Random position order | N/A | Moderate |
| Watson (2005) [43] | Multi-breath helium dilution, spirometry | N/A | N/A | Moderate |
| Yap (2000) [27] | Spirometry, FRC was measured using helium dilution | First position always sitting | 5 min | Moderate |
- Risk of bias was assessed using the Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group [15, 16]
- DLCO Diffusing capacity of the lungs for carbon monoxide, FRC Functional residual capacity
- N/A Not available, not reported in the study