The aim of this study is to review/identify the existing definition and management strategies for a physiologically difficult airway (PDA), to generate expert consensus on the various aspects of managing a patient with a PDA using the Delphi method, and to provide guidance to clinicians worldwide on safe tracheal intubation practices in patients with PDA to help improve patient outcomes.

The Delphi method involves the following 4 steps:

Step 1: Establishing a preliminary list of broad domains

A focused literature review was performed by select membership of the Society of Critical Care Anesthesiologists (SOCCA), and based on their input, the steering committee identified six broad domains, which were used to draft statements for Round one of the Delphi process.

List of domains:

1. Definitions of PDA
2. Preparing the team for airway management in a patient with PDA
3. Preparing the patient with a PDA for success with airway management
4. Performing tracheal intubation
5. Post-intubation care
6. Areas of Future Research

Step 2: Preparation of the Delphi Round One Survey The list of questions related to the above-mentioned domains will be sent to the Experts as a Delphi questionnaire. The anonymity of the Experts will be maintained during the Delphi rounds. The Experts would be requested to answer questions related to PDA based on their experience and knowledge of the subject. The questions will be multiple choice or in the form of a 7-point Likert scale (strongly agree, agree, somewhat agree, neither agree nor disagree, somewhat disagree, disagree, strongly disagree). The experts can also provide their opinion on addition, deletion on questions or choices through free-text. The responses of experts will be collated during the analysis of results and shared in the following survey as controlled feedback.

Step 3: Subsequent Delphi Rounds The steering committee will review the results of round one. The statements listed will be modified, deleted, or added if found ambiguous based on the feedback and comments of the results. The remaining statements will be continued in the subsequent rounds until consensus is achieved (>80% of respondents). The summary results of round two will be presented to experts, and the survey process will be repeated with the modified questionnaire. The Delphi rounds will be continued till desired consensus and stability is achieved for statements. The steering committee will also check the stability using chi-square test of the statements from Round 3 onwards and statement is said to be stable if p-value is > 0.05 for two consecutive rounds.

Step 4: Final Consensus The summary results of the last stable round will be used to issue the consensus on the various statements related to the above-mentioned domains. The results of the final survey, consensus statements, and the manuscript will be circulated among the experts for approval before submission for publication.

Inclusion Criteria:

• Clinical expertise in the airway management of critically ill patients
• Teaching experience in airway management
• Research projects and/or publications in airway management

Exclusion Criteria:

• People don't meet the inclusion criteria

Experts must meet the following three criteria:

Clinical expertise in the airway management of critically ill patients, teaching experience in airway management, and have/had research projects and/or publications in airway management