All India difficult airway association (AIDAA) consensus guidelines for airway management in the operating room during the COVID-19 pandemic.

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) which causes coronavirus disease (COVID-19) is a highly contagious virus. The closed environment of the operation room (OR) with aerosol generating airway management procedures increases the risk of transmission of infection among the anaesthesiologists and other OR personnel. Wearing complete, fluid impermeable personal protective equipment (PPE) for airway related procedures is recommended. Team preparation, clear methods of communication and appropriate donning and doffing of PPEs are essential to prevent spread of the infection. Optimal pre oxygenation, rapid sequence induction and video laryngoscope aided tracheal intubation (TI) are recommended. Supraglottic airways (SGA) and surgical cricothyroidotomy should be preferred for airway rescue. High flow nasal oxygen, face mask ventilation, nebulisation, small bore cannula cricothyroidotomy with jet ventilation should be avoided. Tracheal extubation should be conducted with the same levels of precaution as TI. The All India Difficult Airway Association (AIDAA) aims to provide consensus guidelines for safe airway management in the OR, while attempting to prevent transmission of infection to the OR personnel during the COVID-19 pandemic.

Critical language during an airway emergency: Time to rethink terminology?

Clear language should be used during emergency airway management to aid communication and understand the nature of the emergency. Unfortunately, during emergency airway management, there is no uniform language used for communication. Various difficult airway guidelines use different terminologies. Terminologies like "can't intubate, can't oxygenate" (CICO) and "can't intubate, can't ventilate" (CICV) have certain limitations. Though terminology like "Front of Neck Access" (FONA) is dominant in the literature,"emergency cricothyroidotomy" is used more often in clinical practice, suggesting a disconnect between the dominant terminology in the literature and in clinical practice. Terminology should not be used merely because it is catchy, simple and advocated by a few. It must accurately reflect the nature of the situation, convey a sense of urgency, and suggest an action sequence. An initiative to achieve consensus among existing terminologies is much needed. Leaders in the field should work towards refining airway terminology and replace poor phrases with ones that are more concise, precise and can be used universally in an airway emergency.

Republication: All India Difficult Airway Association 2016 Guidelines for Tracheal Intubation in the Intensive Care Unit.

Tracheal intubation (TI) is a routine procedure in the Intensive Care Unit (ICU) and is often lifesaving. In contrast to the controlled conditions in the operating room, critically ill patients with respiratory failure and shock are physiologically unstable. These factors, along with under evaluation of the airway and suboptimal response to preoxygenation, are responsible for a high incidence of life-threatening complications such as severe hypoxemia and cardiovascular collapse during TI in the ICU. The All India Difficult Airway Association (AIDAA) proposes a stepwise plan for safe management of the airway in critically ill patients. These guidelines have been developed based on available evidence; Wherever, robust evidence was lacking, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the (AIDAA) and Indian Society of Anaesthesiologists. Noninvasive positive pressure ventilation for preoxygenation provides adequate oxygen stores during TI for patients with respiratory pathology. Nasal insufflation of oxygen at 15 L/min can increase the duration of apnea before hypoxemia sets in. High flow nasal cannula oxygenation at 60-70 L/min may also increase safety during intubation of critically ill patients. Stable hemodynamics and gas exchange must be maintained during rapid sequence induction. It is necessary to implement an intubation protocol during routine airway management in the ICU. Adherence to a plan for difficult airway management incorporating the use of intubation aids and airway rescue devices and strategies is useful.

All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in adults.

The All India Difficult Airway Association (AIDAA) guidelines for management of the unanticipated difficult airway in adults provide a structured, stepwise approach to manage unanticipated difficulty during tracheal intubation in adults. They have been developed based on the available evidence; wherever robust evidence was lacking, or to suit the needs and situation in India, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists. We recommend optimum pre-oxygenation and nasal insufflation of 15 L/min oxygen during apnoea in all patients, and calling for help if the initial attempt at intubation is unsuccessful. Transnasal humidified rapid insufflations of oxygen at 70 L/min (transnasal humidified rapid insufflation ventilatory exchange) should be used when available. We recommend no more than three attempts at tracheal intubation and two attempts at supraglottic airway device (SAD) insertion if intubation fails, provided oxygen saturation remains ≥ 95%. Intubation should be confirmed by capnography. Blind tracheal intubation through the SAD is not recommended. If SAD insertion fails, one final attempt at mask ventilation should be tried after ensuring neuromuscular blockade using the optimal technique for mask ventilation. Failure to intubate the trachea as well as an inability to ventilate the lungs by face mask and SAD constitutes 'complete ventilation failure', and emergency cricothyroidotomy should be performed. Patient counselling, documentation and standard reporting of the airway difficulty using a 'difficult airway alert form' must be done. In addition, the AIDAA provides suggestions for the contents of a difficult airway cart.

All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in obstetrics.

The various physiological changes in pregnancy make the parturient vulnerable for early and rapid desaturation. Severe hypoxaemia during intubation can potentially compromise two lives (mother and foetus). Thus tracheal intubation in the pregnant patient poses unique challenges, and necessitates meticulous planning, ready availability of equipment and expertise to ensure maternal and foetal safety. The All India Difficult Airway Association (AIDAA) proposes a stepwise plan for the safe management of the airway in obstetric patients. These guidelines have been developed based on available evidence; wherever robust evidence was lacking, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists (ISA). Modified rapid sequence induction using gentle intermittent positive pressure ventilation with pressure limited to ≤20 cm H2O is acceptable. Partial or complete release of cricoid pressure is recommended when face mask ventilation, placement of supraglottic airway device (SAD) or tracheal intubation prove difficult. One should call for early expert assistance. Maternal SpO2 should be maintained ≥95%. Apnoeic oxygenation with nasal insufflation of 15 L/min oxygen during apnoea should be performed in all patients. If tracheal intubation fails, a second- generation SAD should be inserted. The decision to continue anaesthesia and surgery via the SAD, or perform fibreoptic-guided intubation via the SAD or wake up the patient depends on the urgency of surgery, foeto-maternal status and availability of resources and expertise. Emergency cricothyroidotomy must be performed if complete ventilation failure occurs.

All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in Paediatrics.

The All India Difficult Airway Association guidelines for the management of the unanticipated difficult tracheal intubation in paediatrics are developed to provide a structured, stepwise approach to manage unanticipated difficulty during tracheal intubation in children between 1 and 12 years of age. The incidence of unanticipated difficult airway in normal children is relatively rare. The recommendations for the management of difficult airway in children are mostly derived from extrapolation of adult data because of non-availability of proven evidence on the management of difficult airway in children. Children have a narrow margin of safety and mismanagement of the difficult airway can lead to disastrous consequences. In our country, a systematic approach to airway management in children is lacking, thus having a guideline would be beneficial. This is a sincere effort to protocolise airway management in children, using the best available evidence and consensus opinion put together to make airway management for children as safe as possible in our country.

All India Difficult Airway Association 2016 guidelines for the management of anticipated difficult extubation.

Extubation has an important role in optimal patient recovery in the perioperative period. The All India Difficult Airway Association (AIDAA) reiterates that extubation is as important as intubation and requires proper planning. AIDAA has formulated an algorithm based on the current evidence, member survey and expert opinion to incorporate all patients of difficult extubation for a successful extubation. The algorithm is not designed for a routine extubation in a normal airway without any associated comorbidity. Extubation remains an elective procedure, and hence, patient assessment including concerns related to airway needs to be done and an extubation strategy must be planned before extubation. Extubation planning would broadly be dependent on preventing reflex responses (haemodynamic and cardiovascular), presence of difficult airway at initial airway management, delayed recovery after the surgical intervention or airway difficulty due to pre-existing diseases. At times, maintaining a patent airway may become difficult either due to direct handling during initial airway management or due to surgical intervention. This also mandates a careful planning before extubation to avoid extubation failure. Certain long-standing diseases such as goitre or presence of obesity and obstructive sleep apnoea may have increased chances of airway collapse. These patients require planned extubation strategies for extubation. This would avoid airway collapse leading to airway obstruction and its sequelae. AIDAA suggests that the extubation plan would be based on assessment of the airway. Patients requiring suppression of haemodynamic responses would require awake extubation with pharmacological attenuation or extubation under deep anaesthesia using supraglottic devices as bridge. Patients with difficult airway (before surgery or after surgical intervention) or delayed recovery or difficulty due to pre-existing diseases would require step-wise approach. Oxygen supplementation should continue throughout the extubation procedure. A systematic approach as briefed in the algorithm needs to be complemented with good clinical judgement for an uneventful extubation.

The All India Difficult Airway Association 2016 guidelines for tracheal intubation in the Intensive Care Unit.

Tracheal intubation (TI) is a routine procedure in the Intensive Care Unit (ICU) and is often life-saving. In contrast to the controlled conditions in the operating room, critically ill patients with respiratory failure and shock are physiologically unstable. These factors, along with a suboptimal evaluation of the airway and limited oxygen reserves despite adequate pre-oxygenation, are responsible for a high incidence of life-threatening complications such as severe hypoxaemia and cardiovascular collapse during TI in the ICU. The All India Difficult Airway Association (AIDAA) proposes a stepwise plan for safe management of the airway in critically ill patients. These guidelines have been developed based on available evidence; wherever robust evidence was lacking, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists. Non-invasive positive pressure ventilation during pre-oxygenation improves oxygen stores in patients with respiratory pathology. Nasal insufflation of oxygen at 15 L/min can increase the duration of apnoea before the occurrence of hypoxaemia. High-flow nasal cannula oxygenation at 60-70 L/min may also increase safety during TI in critically ill patients. Stable haemodynamics and gas exchange must be maintained during rapid sequence induction. It is necessary to implement an intubation protocol during routine airway management in the ICU. Adherence to a plan for difficult airway management incorporating the use of intubation aids and airway rescue devices and strategies is useful.

Anatomy and physiology of respiratory system relevant to anaesthesia.

Clinical application of anatomical and physiological knowledge of respiratory system improves patient's safety during anaesthesia. It also optimises patient's ventilatory condition and airway patency. Such knowledge has influence on airway management, lung isolation during anaesthesia, management of cases with respiratory disorders, respiratory endoluminal procedures and optimising ventilator strategies in the perioperative period. Understanding of ventilation, perfusion and their relation with each other is important for understanding respiratory physiology. Ventilation to perfusion ratio alters with anaesthesia, body position and with one-lung anaesthesia. Hypoxic pulmonary vasoconstriction, an important safety mechanism, is inhibited by majority of the anaesthetic drugs. Ventilation perfusion mismatch leads to reduced arterial oxygen concentration mainly because of early closure of airway, thus leading to decreased ventilation and atelectasis during anaesthesia. Various anaesthetic drugs alter neuronal control of the breathing and bronchomotor tone.