At the same time, Margaret Piehl was a nurse working in a small community hospital ICU in America. She noted that when patients with acute respiratory distress syndrome (ARDS) were placed in the prone position their oxygenation levels improved. Margaret described this phenomenon in a ground-breaking paper published in Critical Care Medicine in 1976. Together with physician Robert Brown she described the improvements in arterial oxygenation on 5 patients brought about by “extreme position changes”⁽¹⁾

In the following years other physicians studied this observation to understand who would benefit from the technique, when it should be carried out and how long a patient should be in the prone position. It took many years of clinical trials to confirm that prone positioning improves arterial oxygenation. Finally in 2013 the PROSEVA⁽²⁾ trial was published in the New England journal of Medicine. This trial showed that early intervention with the use of prone positioning in ARDS patients with the most severe hypoxemia resulted in a 17% absolute reduction in mortality. Prone positioning has the most impact on survival of ARDS patients than any other intervention. Thank you, Margaret Piehl, for your keen eye back in 1976.

For over 40 years this remarkable but simple technique has helped save the lives of many ARDS patients in ICU and the world barely noticed. Scroll forward to 2020 and Covid 19 sweeps across the globe. Images appear on our TV screens of ICU’s full of desperately ill Covid 19 patients being treated by incredible nurses and doctors. ARDS is often associated with Covid 19, resulting in many patients being proned. We see proning in action and start to take an interest in Margaret Piehl’s observation.

It can be quite a complicated manoeuvre that is described brilliantly in the Intensive Care Society Guidelines for Prone Positioning in Adult Critical Care⁽³⁾:

• You need at least 5 trained healthcare professionals with someone taking control at the head of the patient.
• Staff are allocated to manage the airway and the drains etc. and are positioned along the side of the patient.
• The patient is on a clean sheet with a slide sheet underneath.
• Pillows are placed strategically on the patient who is then covered with another sheet leaving the head and neck free.
• The edges of the top and bottom sheets are rolled together to tightly wrap the patient.
• The patient is then moved to the edge of the bed and turned through 90°, so they are lying on their side.
• The rolled-up sheet is pulled up from beneath the patient whilst the patient is carefully turned into the prone position.
• All the leads and ETT are checked to ensure they are not kinked.
• The patients’ arms are placed in the “swimmers” position, head turned to one side, and they are nursed at 30° in the reverse trendelenburg position.

• In the supine position, the lungs are compressed by the heart and abdominal organs. Gas exchange is reduced in areas of collapsed lung, resulting in low oxygen levels. In the prone position, lung compression is less, improving lung function.
• The body has mechanisms to adjust blood flow to different portions of the lung. In ARDS, an imbalance between blood and air flow develops, leading to poor gas exchange. Prone positioning redistributes blood and air flow more evenly, reducing this imbalance and improving gas exchange.
• With improved lung function in the prone position, less support from the ventilator is needed to achieve adequate oxygen levels. This may reduce risk of ventilator-induced lung injury, which occurs from overinflation and excess stretching of certain portions of the lung.
• Prone positioning may improve heart function in some patients. In the prone position, blood return to the chambers on the right side of the heart increases and constriction of the blood vessels of the lung decreases. This may help the heart pump better, resulting in improved oxygen delivery to the body.
• Because the mouth and nose are facing down in the prone position, secretions produced by the disease process in the lung may drain better.

The benefits of proning severely ill patients are very clear but there are risks associated with the procedure. Placing patients in this position may put them at risk for complications such as pressure injuries, airway complications, facial injuries, peripheral nerve injuries, musculoskeletal injuries, and cognitive impairment.

The Intensive Care Society Guidelines⁽³⁾ recommend that there should be no direct pressure on the eyes. Unfortunately, this is not always possible and prone nursed patients may suffer direct pressure on the eyes or raised orbital/ophthalmic pressure due to gravitational effects or periocular swelling. This can cause number of complications including acute primary angle closure glaucoma, ischaemic optic neuropathy, vascular occlusion, orbital apex syndrome and corneal abrasions. In a busy ICU full of seriously ill patients taking care of the proned patients’ eyes can be missed. Eye care can contribute enormously to improved patient recovery by ensuring the eyes are not painful or swollen and vision isn’t blurred. Additionally, painful corneal abrasions and infections are avoided.

The Intensive Care Society Guidelines⁽³⁾ recommend that prior to proning, the eyes are assessed, cleaned, ointment applied and then covered with eye coverings. Eye condition should be checked every 2 to 4 hours and corneal clarity checked.

It surely makes sense that the eye covering of choice in this situation should be EyePro.™ which has clear advantages over micropore tape. EyePro™ is sterile and ensures rapid, complete, and safe eyelid closure. By sealing around the eye circumferentially, all moisture is retained, thus preventing the eye from drying out.

Additionally, a clear central window allows direct observation of eyelid closure. EyePro™ was specifically designed for one purpose; to protect the eyes during general anaesthesia. In doing so, EyePro™ provides a superior level of protection against corneal abrasions.