BACKGROUND: Predicting a difficult airway, including difficult laryngoscopy, intubation or mask ventilation, is paramount in peri-operative management. As clinical predictors are only partially reliable, ultrasound-based measurements might be useful in evaluating anterior neck fat tissues depth. OBJECTIVES: The aim of this systematic review is to report clinical evidence on pre-operative ultrasound as a predictor of difficult laryngoscopy, difficult intubation or difficult mask ventilation. DESIGN: A systematic review of randomised controlled trials and observational studies. DATA SOURCES: The MEDLINE, EMBASE and Google Scholar databases were queried from inception until 28 February 2022. ELIGIBILITY CRITERIA: Studies involving adult patients who had undergone orotracheal intubation after evaluation with airways ultrasound were considered suitable. Exclusion criteria were a clinical history of difficult airways, cancer or trauma, pregnancy, supraglottic airway devices, video-laryngoscopy. Parameters were classified by reporting their accuracy in discriminating ‘difficult’ vs. ‘not difficult’ laryngoscopy, intubation or mask ventilation. RESULTS: Thirty-one observational studies were included and a total of 41 single parameters and 12 different combinations of clinical and ultrasound parameters were reported. The distance from skin to epiglottis midway with neutral position of head and neck, the distance from hyoid bone to skin surface with a neutral position of head and neck and the hyomental distance extended/neutral ratio are the most associated with difficult laryngoscopy or difficult intubation. A combination of clinical and ultrasound parameters (a modified Mallampati score, the distance from the skin to the epiglottis midway with neutral position of the head and neck, and the USED-MSH score) showed high accuracy. Only two studies reported the role of ultrasound in predicting difficult mask ventilation: the distance from hyoid bone to skin surface with neutral position of head and neck, the thickness of the base of the tongue with hyperextension of the head, and the hyomental distance with hyperextension of the head and active subluxation of the mandible are the parameters with the highest correlation. CONCLUSIONS: The use of ultrasound parameters might be useful in predicting difficult laryngoscopy or difficult intubation. Several ultrasound parameters and combinations have been associated with difficult laryngoscopy or difficult intubation prediction. The use of scores combining clinical predictors and ultrasound measures are very promising. Data on difficult mask ventilation are scarce and the role of ultrasound is still controversial. Future studies are needed. CLINICAL TRIAL REGISTRATION: CRD42021250574.

Delayed neurocognitive recovery and postoperative neurocognitive disorders are major complications of surgery, hospitalization, and anesthesia that are receiving increasing attention. Their incidence is reported to be 10–80% after cardiac surgery and 10–26% after non-cardiac surgery. Some of the risk factors include advanced age, level of education, history of diabetes mellitus, malnutrition, perioperative hyperglycemia, depth of anesthesia, blood pressure fluctuation during surgery, chronic respiratory diseases, etc. Scientific evidence suggests a causal association between anesthesia and delayed neurocognitive recovery or postoperative neurocognitive disorders, and various pathophysiological mechanisms have been proposed: mitochondrial dysfunction, neuroinflammation, increase in tau protein phosphorylation, accumulation of amyloid-β protein, etc. Insulin receptors in the central nervous system have a non-metabolic role and act through a neuromodulator-like action, while an interaction between anesthetics and central nervous system insulin receptors might contribute to anesthesia-induced delayed neurocognitive recovery or postoperative neurocognitive disorders. Acute or chronic intranasal insulin administration, which has no influence on the blood glucose concentration, appears to improve working memory, verbal fluency, attention, recognition of objects, etc., in animal models, cognitively healthy humans, and memory-impaired patients by restoring the insulin receptor signaling pathway, attenuating anesthesia-induced tau protein hyperphosphorylation, etc. The aim of this review is to report preclinical and clinical evidence of the implication of intranasal insulin for preventing changes in the brain molecular pattern and/or neurobehavioral impairment, which influence anesthesia-induced delayed neurocognitive recovery or postoperative neurocognitive disorders.

Introduction: Coronavirus disease 2019 (COVID-19) is a significant and novel cause of acute respiratory distress syndrome (ARDS). During the COVID-19 pandemic, there has been an increase in the incidence of cases involving pneumothorax and pneumomediastinum. However, the risk factors associated with poor outcomes in these patients remain unclear. Methods: This observational study collected clinical and imaging data from COVID-19 patients with PTX and/or PNM across five tertiary hospitals in central Italy between 1 March 2020 and 1 March 2022. This study also calculated the incidence of PTX and PNM and utilized multivariable regression analysis and Kaplan–Meier curve analysis to identify predictor factors for 28-day mortality and 3-day orotracheal intubation after PTX/PNM. This study also considered the impact of the three main variants of concern (VoCs) (alfa, delta, and omicron) circulating during the study period. Results: During the study period, a total of 11,938 patients with COVID-19 were admitted. This study found several factors independently associated with a higher risk of death in COVID-19 patients within 28 days of pulmonary barotrauma. These factors included a SOFA score ≥ 4 (OR 3.22, p = 0.013), vasopressor/inotropic therapy (OR 11.8, p < 0.001), hypercapnia (OR 2.72, p = 0.021), PaO₂/FiO₂ ratio < 150 mmHg (OR 10.9, p < 0.001), and cardiovascular diseases (OR 7.9, p < 0.001). This study also found that a SOFA score ≥ 4 (OR 3.10, p = 0.015), PCO₂ > 45 mmHg (OR 6.0, p = 0.003), and P/F ratio < 150 mmHg (OR 2.9, p < 0.042) were factors independently associated with a higher risk of orotracheal intubation (OTI) within 3 days from PTX/PNM in patients with non-invasive mechanical ventilation. SARS-CoV-2 VoCs were not associated with 28-day mortality or the risk of OTI. The estimated cumulative probability of OTI in patients after pneumothorax was 44.0% on the first day, 67.8% on the second day, and 68.9% on the third day, according to univariable survival analysis. In patients who had pneumomediastinum only, the estimated cumulative probability of OTI was 37.5%, 46.7%, and 57.7% on the first, second, and third days, respectively. The overall incidence of PTX/PNM among hospitalized COVID-19 patients was 1.42%, which increased up to 4.1% in patients receiving invasive mechanical ventilation. Conclusions: This study suggests that a high SOFA score (≥4), the need for vasopressor/inotropic therapy, hypercapnia, and PaO₂/FiO₂ ratio < 150 mmHg in COVID-19 patients with pulmonary barotrauma are associated with higher rates of intubation, ICU admission, and mortality. Identifying these risk factors early on can help healthcare providers anticipate and manage these patients more effectively and provide timely interventions with appropriate intensive care, ultimately improving their outcomes.

Background: The aim of this study was to assess whether procalcitonin levels is a diagnostic tool capable of accurately identifying sepsis and ventilator-associated pneumonia (VAP) even in critically ill COVID-19 patients. Methods: In this retrospective, observational study, all critically ill COVID-19 patients who survived for ≥2 days in a single university hospital and had at least one serum procalcitonin (PCT) value and associated blood culture and/or culture from a lower respiratory tract specimen available were eligible for the study. Results: Over the research period, 184 patients were recruited; 67 VAP/BSI occurred, with an incidence rate of 21.82 episodes of VAP/BSI (95% CI: 17.18–27.73) per 1000 patient-days among patients who were included. At the time of a positive microbiological culture, an average PCT level of 1.25–3.2 ng/mL was found. Moreover, also in subjects without positive cultures, PCT was altered in 21.7% of determinations, with an average value of 1.04–5.5 ng/mL. Both PCT and PCT-72 h were not linked to a diagnosis of VAP/BSI in COVID-19 patients, according to the multivariable GEE models (aOR 1.13, 95% CI 0.51–2.52 for PCT; aOR 1.32, 95% CI 0.66–2.64 for PCT-72 h). Conclusion: Elevated PCT levels might not always indicate bacterial superinfections or coinfections in a severe COVID-19 setting.