Prone: Let’s Not Get It Back To Front

In this activity, we’ll discuss proning: how it helps, why transferring in the prone position might be necessary and how this can be performed safely. The transfer of critically ill patients carries significant risks, especially when patients have respiratory and cardiovascular instability and are mechanically ventilated…

…and all this is even trickier when proned!

• Proned ventilation improves survival in patients with severe acute respiratory distress syndrome (ARDS) as demonstrated by the PROSEVA trial.

When performed by experienced and familiar staff proning can be safe with minimal to no complications.

A proned patient on the way to the ambulance

• Proning in ARDS patients improves oxygenation, promotes lung protective ventilation and minimises ventilator associated lung injury, with the benefits divided into ventilation and perfusion categories.

Proning Comes With Certain Risks…

• During turning lines and tubes can become dislodged. Lines and tubes can malfunction and the patient can experience persistent hypoxia and haemodynamic instability.
• Cardiovascular and respiratory instability can become apparent and life-threatening and there is almost always need for increased sedation and the use of neuromuscular blocking agents.
• Pressure sores on the face, chest and pelvis. Eyes are particularly prone to injury such as retinal damage, conjunctival oedema or haemorrhage.

The risk of complications is raised in the following conditions and careful consideration should be weighted. – raised intra-abdominal and intra-cranial pressure, spinal fractures or instability, pelvic fractures, severe haemodynamic instability and pregnancy

• The decision to prone a patient should be assessed on a case-by-case basis.

Why Would It Be Needed?

• ARDS and refractory hypoxaemia carry significant mortality. Available treatments are somewhat limited, such as supportive care with Extracorporeal Membrane Oxygenation (ECMO).
• ECMO is available in Severe Respiratory Failure (SRF) centres which the patient needs to be transferred to. The best option for patient safety is to transfer the patient already established on ECMO, which is often done by a specialist ECMO team at the referral hospital who then also retrieve the patient. See more on ECMO later in the week.
• However, ECMO pre-transfer is not always possible for logistical reasons. In these situations, the patient needs to be transferred to the SRF centre before ECMO, which can be challenging.
• The patients are usually severely hypoxic and haemodynamically unstable, and often are already prone in order to achieve adequate gas exchange. De-proning the patient for transfer may decompensate the gas exchange and make the patient unsafe for transfer.

Transfer in the prone position in these situations is the safest – and possibly the only – option.

Patient prepared for a prone transfer

The Prone Practicalities

• Consensus of the plan by the entire crew is necessary and discussing concerns and troubleshooting in advance is essential. Maintain good communication informing all parties at both referring and receiving hospitals.

All necessary interventions should take place prior to proning if the patient is supine prior to the transfer (e.g. line insertion, bronchoscopy, drain insertion)

• Consider deepening sedation and the use of neuromuscular blockade.
• Transfer onto the stretcher using a horizontal pull if already prone, or if supine the patient can be proned directly onto the stretcher.
• Particular attention needs to be paid to securing lines and tubes.

• The face and endotracheal tube (ETT) should be facing towards the medical team during the transfer. Avoid excessive pressure on critical points of the face (eyes, nose, ears). The use of a silicone or towel ring on an anaesthetic pillow if available is useful for this. Silicone pads can be used to shield the shoulders, pelvis and knees from pressure.
• The arms are usually placed by the side of the patient (in contrast to the ‘swimmer’s position’ commonly used on ICUs) mainly due to the limited space on a stretcher. In some cases, the arms are placed by the patient’s head – for example in bariatric patients.
• The patient should then be secured at 3 distinct points as a minimum with stretcher straps to avoid unwanted movement along the stretcher.