A review of the first 4000 reports to the webAIRS anaesthesia incident reporting database was performed to analyse cases reported as difficult or failed intubation. Patient, task, caregiver and system factors were evaluated. Among the 4000 reports, there were 170 incidents of difficult or failed intubation. Difficult or failed intubation incidents were most common in the 40–59 years age group. More than half of cases were not predicted. A total of 40% involved patients with a body mass index >30 kg/m2 and 41% involved emergency cases. A third of the reports described multiple intubation attempts. Of the reports, 18% mentioned equipment problems including endotracheal tube cuff rupture, laryngoscope light failure, dysfunctional capnography and delays with availability of additional equipment to assist with intubation. Immediate outcomes included 40 cases of oxygen desaturation below 85%; of these cases, four required cardiopulmonary resuscitation. The majority of the incidents resulted in no harm or minor harm (45%). However, 12% suffered moderate harm, 3.5% severe harm and there were three deaths (although only one related to the airway incident). Despite advances and significant developments in airway management strategies, difficult and failed intubation still occurs. Although not all incidents are predictable, nor are all preventable, the information provided by this analysis might assist with future planning, preparation and management of difficult intubation.

This audit of airway incidents was conducted over six months in 12 tertiary level hospitals across Australia and New Zealand. During that time, 131,233 patients had airway management and 111 reports were submitted (incidence 0.08%). The airway incidents included a combination of difficult airway management (83), oxygen desaturation (58), aspiration (19), regurgitation (14), laryngospasm (16), airway bleeding (10), bronchospasm (5) and dental injury (4), which gave a total of 209 events in 111 reports. Most incidents occurred during general anaesthesia (GA; 83.8%) and normal working hours (81.1%). Forty-three percent were associated with head and neck surgery and 12.6% with upper abdominal procedures. Of these patients, 52% required further medical treatment or additional procedures and 16.2% required unplanned admission to an intensive care unit or a high dependency unit. A total of 31.5% of patients suffered from temporary harm and 1.8% from permanent harm. There was one death. The factors associated with a high relative risk (RR) of an airway incident included American Society of Anesthesiologists Physical Status (ASA PS) (ASA PS 2 versus 1, RR 1.75; ASA PS 3 versus 1, RR 3.56; ASA PS 4 versus 1, RR 6.1), and emergency surgery (RR 2.16 compared with elective). Sedation and monitored anaesthesia care were associated with lower RRs (RR 0.49 and RR 0.73 versus GA, respectively). Inadequate airway assessment, poor judgement and poor planning appeared to be contributors to these events. Future teaching and research should focus on these areas to further improve airway management and patient safety.

Purpose of review The purpose is to show the advantages of a Bowtie diagram as a versatile tool for displaying and understanding the evolvement and management of critical incidents. Recent findings The Bowtie diagram has been used recently in anesthesia to depict critical incidents having been used in high-risk industries for several decades. This diagram displays the progression from latent factors to potential harm in five steps. Summary The Bowtie diagram combines the features of a fault tree and an event tree with the adverse event, known as the Top Event separating the two sections. The fault tree is similar in concept to a Swiss Cheese diagram and the event tree similar in concept to an emergency management algorithm. Preventive barriers and escalation measures are used to detect and trap abnormal states. If these fail, the event proceeds to a crisis, leading to the Top Event, a time for making decisions. A recovery state follows, which depicts an emergency state mandating immediate life or limb-saving management to recover from the crisis. Finally, in the aftermath state, a time for reflection and learning, ultimate outcomes are shown in the right-hand column. Video abstract The Bowtie Diagram. Designed and created by Yasmin Endlich, Martin D. Culwick and Stavros N. Prineas.