HEAVEN Criteria: Prediction of Difficult Airway for In- Hospital Emergency Airway Management

Study Overview
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Brief Summary
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The HEAVEN criteria were found valid to predict difficult airways during preclinical emergency intubations in a retrospective study. The acronym stands for Hypoxemia, Extremes of size, Anatomic abnormalities, Vomit/blood/fluid, Exsanguination/anaemia, and Neck mobility issues. This is a monocentric prospective observational study to assess the validity of the HEAVEN criteria in the in-hospital setting at a level I adult and pediatric emergency university-based hospital.

Detailed Description
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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.

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

Conditions
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Respiratory Failure

Intervention / Treatment
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* Procedure: Rapid sequence induction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All consecutive patients of all ages who need an in-hospital rapid sequence intubation (RSI) performed by the staff of the Department of Anesthesiology and Pain Medicine Given general consent or delayed obtained general consent after the procedure English, German or French speaking patients Exclusion Criteria: • Patients without informed consent
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients that need emergency rapid sequence inductions<br>Patients of all ages who need emergency rapid sequence inductions due to their medical condition performed by the staff of the Department of Anaesthesiology and Pain Medicine at the Bern University Hospital. We defined emergency as a non scheduled intervention with immediate (or maximum up to 6 hours after announcement) need of general anaesthesia (e.g. trauma patients with need for emergency surgery) and therefore appropriate fastening is not possible. | Procedure: Rapid sequence induction<br>* Rapid sequence induction starts with the administration of rapid acting intravenous narcotics, opioids and neuromuscular blockage and avoids whenever possible positive-pressure ventilation after induction of anesthesia.<br>|
| Patients that need scheduled rapid sequence inductions<br>Patients of all ages who need scheduled rapid sequence inductions due to their medical condition performed by the staff of the Department of Anaesthesiology and Pain Medicine at the Bern University Hospital. Patients of this cohort have a scheduled intervention and therefore can fasten meals for at least 6 hours before induction of general anaesthesia. | Procedure: Rapid sequence induction<br>* Rapid sequence induction starts with the administration of rapid acting intravenous narcotics, opioids and neuromuscular blockage and avoids whenever possible positive-pressure ventilation after induction of anesthesia.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients with first-attempt success rate of RSI | Every attempt starts with the insertion of a laryngoscope blade over the lips and ends with a blocked tube in the trachea and measuring of carbon dioxide (CO2) | 1 hour | 
| Patients with difficulty of intubation | Rated on a scale by the airway manager: easy, difficult, not possible | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall success rate of rapid sequence induction (RSI) | All RSI during the study period are analyzed for success (If intubation is possible or not) | 1 hour | 
| Patients with first-attempt success without desaturation SpO2 <92% during RSI | Saturation will be measured and recorded during the whole intervention and analyzed for the time of the RSI. | 1 hour | 
| Total attempts of intubation in a patient | Every attempt starts with the insertion of a laryngoscope blade over the lips and ends with a blocked tube in the trachea and measuring of CO2 | 1 hour | 
| Cormack & Lehane grade (C&L) or Percentage of Glottis Opening (POGO) in a patient | C&L for direct laryngoscopy or POGO for video laryngoscopy will be recorded for every intubation | 1 hour | 
| Lowest and highest recorded value of patients' heart rate (HR) during RSI | Heart rate will be measured and recorded during the whole intervention and analyzed for the time of the RSI. | 1 hour | 
| Lowest and highest recorded value of patients' blood-pressure (BP) during RSI | BP will be measured and recorded during the whole intervention and analyzed for the time of the RSI. | 1 hour | 
| Lowest and highest recorded value of patients' oxygen saturation (SpO2) during RSI | SpO2 will be measured and recorded during the whole intervention and analyzed for the time of the RSI. | 1 hour | 
| Patients with use of vasoconstrictors during RSI | Use of vasoconstrictors will be recorded during the whole intervention and analyzed for the time of the RSI. | 1 hour | 
| Patients with use of devices/ techniques for intubation | Use of: supraglottic airway device (SAD) intubation guides (Frova, S-Guide) video laryngoscopy (VL) or direct laryngoscopy, shape and size of the blade, flexible scope rigid stylets (C-MAC VS, Bonfils) intubation over SAD emergency front of neck access (eFONA) | 1 hour | 
| Patients with use and type of neuromuscular blockage agent | Yes / No, if Yes, specify: Succinylcholine, Rocuronium, Atracurium, other | 1 hour | 
| Patient's demographics | Patient's age, gender, weight and size | 1 hour | 
| Type of planned procedure | type of surgery by discipline (e.g. ear, nose and throat (ENT), visceral, orthopedic, heart, urology, gynecology) and specification (e.g. appendectomy) | 1 day | 
| Place of intubation | The place where the intubation is performed. Either operation room (OR) or outside OR | 1 day | 
| Time of intubation | the exact time (HH:MM:SS) in central european time of the induction of the RSI | 1 hour | 
| Level of airway manager | nurse, resident or attending anaesthesiologist | 1 hour | 
| Endotracheal tube (ETT) | Type and size of the used ETT(s) during the RSI attempt(s) | 1 hour | 
| Patients with airway-related injuries like blood, damage to tissue, lips or teeth caused directly during intubation | Will be directly recorded if occurred during the RSI by the airway manager or team | 1 hour | 
| Patients with airway-related complains like hoarseness or problems with swallowing until 24 hours after intubation reported subjectively by the patient | All patients will be visited in the first 24 hours after anaesthesia if they report subjectively airway-related complains like hoarseness or problems with swallowing until 24 hours after intubation and evaluated by an anaesthesiologist or further referred to an ENT specialist | 1 day | 
| Patients with suspicion of aspiration during RSI | Newly recorded suspicion of aspiration during intubation will be recorded by the airway team | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Emergency Medicine, Intubation, Intratracheal, Anesthesiology, Rapid Sequence Induction, Difficult Airway, Prediction Tool