Flight Criteria: Matching the Patient, Resource and Clinical Need

One of the most consequential decisions in helicopter emergency medical services is made before the aircraft leaves the ground:

Is HEMS the most appropriate resource for this patient?

At ROCKET HEMS, flight criteria provide a structured and clinically defensible framework for answering this question. At every stage of the assessment, the patient remains central to the decision.

The purpose is not simply to determine whether a patient is critically ill or injured. It is to establish which available resource and clinical pathway will provide the most appropriate care, within the required timeframe and with the lowest reasonable transport risk.

Image credit: Stefan Schlimmer

This assessment considers three principal clinical factors:

• Acuity: The severity of the patient’s current illness or injury, including physiological instability, immediate clinical risk and the level of intervention or monitoring required.

  
  

• Progressiveness: Whether the patient’s condition is deteriorating, the anticipated rate of deterioration and the likelihood of further physiological compromise without timely intervention.

  
  

• Consequence: The probable effect of delayed intervention, delayed transfer or delayed access to definitive care.

These factors form part of a broader patient-centred question:

What meaningful clinical difference can HEMS make for this patient?

For some patients, the benefit is reduced time to definitive care or a time-critical intervention. For others, it is the ability to bring advanced critical care capability directly to a location where that level of care is not immediately available.

HEMS may also provide the most appropriate transport pathway for a critically ill or injured patient whose physiology, clinical requirements or geographical location makes prolonged ground transfer unsuitable. In these circumstances, the aircraft may offer a combination of access, speed, specialist clinical capability and an appropriate transport environment that cannot be achieved effectively by other available resources.

However, serious illness or injury does not automatically justify helicopter activation. In some cases, ground transport, local stabilisation or an alternative clinical pathway may provide the safest and most appropriate response.

A patient-centred decision therefore considers the complete clinical and operational context, including:

• The patient’s current physiological condition

• The risk and rate of deterioration

• The intervention or level of care required

• The time required to reach definitive treatment

• The capability of the referring and receiving facilities

• The clinical risks associated with ground and air transport

• The patient’s location and accessibility

• Weather, aviation and landing-site considerations

• Aircraft availability and operational feasibility

• The comparative benefit that HEMS can provide

The decision to fly must be based on whether HEMS offers a meaningful advantage for the patient, rather than on the availability of the aircraft alone.

Flight Criteria: Ensuring Clinical Integrity in HEMS Activation Decisions

Clinical eligibility and funding authorisation are separate considerations. The first responsibility is to determine whether HEMS is clinically indicated, operationally appropriate and likely to benefit the patient. Funding processes may affect how the resource is accessed, but they should not redefine the patient’s clinical need or influence the integrity of the initial assessment.

Every activation decision draws on information from the ROCKET Command Centre, Clinical-on-Call team, medical crew and pilots. Each contributes a different component of the assessment, including clinical urgency, logistical requirements, transport risk, environmental conditions and aviation feasibility.

Enhancing Decision-Making in HEMS Through Multidisciplinary Evaluation and Continuous Review

This multidisciplinary process supports a balanced decision that considers not only whether the mission can be conducted, but whether it should be conducted in the patient’s best interests.

Emergency medical decisions are frequently made using incomplete or evolving information. Flight criteria must therefore support sound professional judgement rather than replace it. As the patient’s condition, location or clinical requirements change, the suitability of HEMS may need to be reassessed.

Ongoing review of accepted, declined and cancelled missions forms an essential part of clinical governance. This enables the service to evaluate whether flight criteria are being applied consistently, identify opportunities for improvement and strengthen future patient-selection and tasking decisions.

Measuring HEMS Effectiveness: Quality Over Quantity

An effective HEMS service is not measured by the number of missions flown. It is measured by the quality, consistency and clinical integrity of its decisions.

The central objective remains clear:

to keep the patient at the centre of every assessment and deploy the right resource at the right time, for the right clinical reason.