Supraglottic airway devices (SADs) have revolutionised perioperative airway management. These devices have contributed significantly to airway management, especially in the context of anticipated or unanticipated difficult airway, thereby decreasing airway-related morbidity. The use of these devices is now accepted even for positive pressure ventilation due to better seal and modifications (such as a double cuff or cuff material) preventing gastric insufflation with lesser chances of regurgitation. The quality of seal depends on how accurately the cuff matches the dimensions of the laryngeal inlet. Various methods and techniques are used for confirming the optimal placement of SADs with variable success rate. Evaluation based on conventional clinical tests is most commonly used for assessing the correct placement of SADs. However, clinical tests have been associated with limited outcome as they may not definitely be able to detect improper placement of SAD. Malpositioning may increase the incidence of complications such as altered airway dynamics, gastric insufflation, regurgitation and aspiration of gastric contents. The accuracy of these tests to identify malposition has been questioned by recent studies where fibreoptic evaluation of position of SAD identified many unacceptable placements which had been considered acceptable on the basis of clinical tests. Another limitation of these tests is that they fail to provide anatomic evidence of optimal SAD placement. Thus, other methods are required to confirm SAD position to avoid adverse events related to the airway. This review elaborates on the use of ultrasound to assess the optimal placement of supraglottic airway devices.

High-flow nasal cannula (HFNC) is a relatively new mode of oxygen supplementation. Warmed and humidified air/oxygen mixtures are delivered at high flows via a nasal cannula to patients. There are many observed physiological benefits for the use of HFNC. There is, therefore, increasing interest surrounding the use of HFNC in adult patients for improving oxygenation. This highly versatile device has been studied expansively in different clinical scenarios, from critical care, to the operating theatre, and even in palliative care. The usefulness of HFNC in management of the global pandemic of coronavirus disease 2019 further attests to its potential. However, evidence surrounding HFNC is still largely inconclusive. More high-quality randomised studies should be conducted to evaluate and justify the routine use of HFNC. Research efforts focused on developing clinical strategies on initiation, monitoring, escalation, de-escalation and titration will contribute to developing more precise guidelines for HFNC therapy.

The choice of an appropriate study design is one of the crucial steps in the research process after framing a research question. A single research question may fit into different study designs. Each design has its own merits and drawbacks; diligence in implementing the methodology and data collection reflects good study design. Sample size justification and power analysis are foundations of a study design. They should ideally be settled when framing a research question and creating the study design. An adequate sample size minimises random error or chance occurrence. 'A just large enough' sample supports the researcher to estimate expected cost, time and feasibility. The sample 'size' is a tug-of-war between reality and scientific effectiveness and is highly influenced by study designs. Null hypothesis (H₀) is the assumption that there is no difference in the treatment groups, whereas an assumption that there is a difference is called alternate hypothesis (H_a). Type I error (α) finds difference in the absence of one (false-positive conclusion), whereas Type II error (β) indicates probability of false-negative results. If the calculated P value is smaller than α, the researcher rejects the null hypothesis (H₀) and welcomes the alternative hypothesis (Ha). There are several validated software available for sample size calculation. Sample size tends to be smaller for means than percentages. As the sample size increases, the P value tends to become small. Finally, a statistically significant result might not always be clinically relevant.

Various modalities such as cryoprobe-transbronchial lung biopsy (TBLB)/transbronchial lung cryobiopsy (TBLC) have been described for lung biopsy procedure. However, anaesthetic concerns related to periprocedural planning for paediatric TBLC have not been previously reported in the literature as clinical experience with paediatric TBLC is just evolving. The airway and general anaesthetic management of TBLC in a 12-year-old girl is described. TBLC in a child requires rigid bronchoscopy under general anaesthesia by an experienced endoscopist who, along with the anaesthesiologist, is alert all the time to keep the peak airway pressures low to avoid barotrauma.

Being prepared for airway management is of paramount importance in any anaesthetic. This involves knowledge, skill, comprehensive assessment and strategic planning. We present the case of a 17-year-old boy who developed tracheal stenosis following a low-level tracheostomy for prolonged ventilation after polytrauma 2 years prior. The stenosed trachea had been resected and anastomosed 9 months earlier. The patient now presented for brachial plexus repair for a flail dominant right hand. Comprehensive assessment with special focus on the airway, anticipation, interdisciplinary communication with the neurosurgeon and otorhinolaryngological surgeon and consensus planning help in an uneventful and successful surgery.

Airway management in polytrauma patients can create unanticipated challenges, particularly in the presence of tracheal injury. A 24-year-old male who suffered a road traffic accident was diagnosed with complete tracheal disruption with a gap of 3.5 cm with minimal external signs of injury. Initial intubation attempts revealed resistance at 18 cm from the angle of the mouth with the endotracheal tube creating a visible contour just below the skin in the midline of the neck. Associated palpable crepitus in the neck led to the suspicion of tracheal disruption. The patient was then intubated using a bougie. The tube was pushed into the bronchus distal to the suspected gap and then withdrawn to lie just above the carina, thereby providing adequate ventilation and preventing further development of subcutaneous emphysema. Associated injuries were managed by multidisciplinary consultations. Prompt thinking and quick clinical decisions with respect to the airway proved to be life-saving for the patient.