HEAVEN Criteria: a Monocentric Prospective Observational Study to Validate the Prediction of Difficult Airway for In-Hospital Emergency Airway Management

Emergency intubations are prone to present a difficult airway. A difficult airway can lead to prolonged intubation time and to hypoxemia in situations where oxygenation is not possible that can finally result in hypoxic cardiac arrest and irreversible brain damage caused by hypoxic ischemic encephalopathy.

Tools to predict difficult airways are rather poor concerning specificity and sensitivity. A score to predict difficult airway developed in the pre-clinical setting are the HEAVEN criteria. The acronym HEAVEN stands for: Hypoxemia, Extremes of size, Anatomic abnormalities, Vomit/blood/fluid, Exsanguination/anaemia, and Neck mobility issues and does not need patients' cooperation. It has been recently validated in the pre-clinical emergency setting and was found to be useful.

The study aim is to evaluate if the HEAVEN criteria are suitable to be used to predict difficult airway in in-hospital emergency intubation to finally increase patients' safety during rapid sequence induction (RSI).

This prospective observational single-centre study in emergency intubation will consecutively recruit all patients of all ages who need RSI due to their medical condition performed by the staff of the Department of Anaesthesiology and Pain Medicine at the Bern University Hospital. We will record data that are gathered during routine patient care and stored primarily in the departmental anaesthesia information systems.

The primary objective is to validate if the HEAVEN criteria, an existing prehospital difficult airway prediction tool, is able to predict airways difficulties during RSI in the clinical in-hospital setting. The secondary objective is, to assess the subcomponent of the HEAVEN criteria and if differences and adaptations are needed comparing it to the prehospital setting.