Of the 146 articles on the use of prone positioning in patients with respiratory conditions that were identified, 32 were relevant to non-mechanically ventilated patients but only five provided details of a proning procedure. Of the remaining 27 studies, two focused on nerve injury relating to prone positioning; a case study (38) and a case series (39). The case series found that 15% of 83 patients admitted to inpatient rehabilitation facilities post-COVID-19 were diagnosed with peripheral nerve injury, 92% of whom had been proned in acute care. Five studies examined patients with ARDS (22, 40–43).
The remaining 25 studies included patients with COVID-19 infection supported with non-invasive ventilation. One study sought to describe sputum characteristics of patients with severe COVID-19, and to determine the effect of airway clearance methods on outcomes in these patients (47) whilst another examined the expansion of the lungs in supine versus prone in COVID-19 using CT scan (48).
The optimal duration of proning has not been determined. Three studies reported a duration of 3 hours or fewer (24, 28, 32), 5 studies reported a duration over 3 hours per day (26, 29, 30, 36, 50), and 3 reported a range across patients: <1hour, 1–3 hours and >3 hours (34), 1–16 hours (25), up to 24 hours a day (35) and 5 studies did not report the duration of proning (27, 31, 33, 37, 49). The results of the studies which did report duration of proning did not provide conclusive evidence to suggest a consensus on optimal duration in the COVID-19 population, although studies that compared duration show a trend towards longer duration being of greater benefit (34, 35).
Five of the 32 studies provided significant detail on the methods of a proning procedure (24, 36, 44–46) and were used to develop our protocol. Two tested the protocol in patients with non-invasive ventilation (24, 36), and 3 described a protocol but did not test it in patients (44–46). Using the data from these 5 articles and from relevant clinical guidelines (51–54), coupled with clinical experience, a protocol was designed by a multidisciplinary team with expertise in caring for older adults with acute COVID-19 infection.
Protocol
This protocol, shown in Figure 1, covers the indications, proning manoeuvre and requisite monitoring. The proning manoeuvre to assist an individual from supine to prone is shown in Figure 2.
Step 1 — Patient selection and suitability
Prone positioning can be trialled for patients who require supplemental oxygen to maintain saturations ≥92% (or ≥88% in the presence of hypercapnic respiratory failure), without severe delirium or impairment in cognition that would preclude compliance with the procedure. Contraindications include spinal instability, unstable pelvic or facial fracture, anterior open wounds or burns, and raised intracranial pressure. In the presence of any relative contraindications, including head injury, uncontrolled seizures, raised intraocular pressure, cardiovascular instability, delirium and morbid obesity, clinical judgement should be used to balance the potential risks and benefits which should be discussed with the patient wherever possible. The relative risks and benefits should be explained, and consent gained where feasible.
Step 2 — Assemble equipment
Up to five staff members may be necessary depending on the degree of assistance required, and appropriate personal protective equipment (PPE) should be worn. The patient’s ability to rotate their cervical spine and head to 45–90° should be checked. All clothing and jewellery should be removed to minimise the risk of a subsequent pressure injury. In advance of the manoeuvre, adequate tubing length and positioning should be checked anticipating the eventual prone position. Suction should be available and functioning. Pre-oxygenation with high flow oxygen via a non-rebreathe mask may be considered where exertion leads to critical desaturation. Given the higher risk to this population of developing pressure injuries, it is strongly recommended that patients should be on an air mattress. Bladder catheter tubing and bags should be placed on the bed, between the legs, rather than affixed to the bedside.
Step 3 — Recording of observations
Older adults are more prone to pressure injury and therefore specific care should be taken of the face, malar area, ears, eyes, shoulders, elbows, breasts, iliac crests, knees and toes (55). Particular attention should be paid to the bridge of the nose for those wearing a face mask, the columella for those wearing nasal cannulae, and the tops of the ears in both instances. Prior to the proning manoeuvre, it is recommended that anterior electrocardiographic electrodes are removed if in situ. These can be reapplied to the posterior chest post-manoeuvre if electrocardiographic monitoring is required. Skin integrity and heart rate, blood pressure, oxygen saturations, temperature, respiratory rate and conscious level should be monitored (51, 54).
Step 4 — Proning manoeuvre
Patients should be encouraged to position themselves independently where they are able. If assistance is required, one individual should co-ordinate the manoeuvre which is achieved by means of a slidesheet-assisted manual handling technique (Figure 2). Once positioning, secretions should be suctioned, and bed angled to 10° (reverse Trendelenburg) which increases adherence, and reduces aspiration risk (52).
Step 5 — Monitoring
Once in the prone position, observations should be recorded at 15 minute intervals for the first hour and according to clinical judgement thereafter. The optimal duration of proning is uncertain with studies of proning in COVID-19 infection reporting a duration of 1–21 hours per day (34, 36). Establishing treatment goals early on will allow the team to assess whether the patient is responding to the proning protocol. There is no strong evidence base to guide the duration after which an individual can be deemed to have responded. Therefore response should be assessed according to clinical judgement with regular proning cycles implemented thereafter in those with satisfactory response. Our experience has been to prone patients as tolerated with shorter recurrent periods prone often facilitating adequate nutrition and hydration at mealtimes. Hourly repositioning, alternating flexion and extension of the arms, with head turned “face facing hand” should be undertaken. If the patient is unable to comply with the positioning requirements we do not advocate the use of physical restraints. Eyes should be lubricated, and face skin should be protected with hyper-oxygenated fatty acids and silicone dressings. Pillows can offload bony prominences such as shoulders, knees, toes and iliac crests and support the chest (52). Ensure oxygen delivery systems are correctly fitted and not too tight across pressure areas.
Step 6 — Post-manoeuvre
After repositioning, observations should be recorded, monitoring particularly for hypotension which can occur during sudden positional changes (56, 57).
Risks and special considerations
If the patient is receiving nutrition via nasogastric (NG) tube, this should be discontinued or aspirated at least one hour prior to the manoeuvre and prone, feed can be restarted at 10ml/h.
Recognised complications of proning include brachial plexus injury (38, 39), pressure ulcers (58, 59) and hypotension on returning to supine (57). As such, regular assessment of pain using a recognised pain score is useful. Proning precludes anterior chest wall observation and there is a risk that recognition of deterioration can be delayed. Whilst successful resuscitation is described in the prone position (60) we advocate that the patient is immediately returned to supine should this need arise. Staffing levels may be a significant factor in limiting feasibility in ward environments, and as such proning should be scheduled to allow for sufficient monitoring.