Point of care ultrasound: a clinical decision support tool for COVID-19

The COVID-19 global pandemic has overwhelmed health services with large numbers of patients presenting to hospital, requiring immediate triage and diagnosis. Complications include acute respiratory distress syndrome, myocarditis, septic shock, and multiple organ failure. Point of care ultrasound is recommended for critical care triage and monitoring in COVID-19 by specialist critical care societies, however current guidance has mainly been published in webinar format, not a comprehensive review. Important limitations of point of care ultrasound include inter-rater variability and subjectivity in interpretation of imaging findings, as well as infection control concerns. A practical approach to clinical integration of point of care ultrasound findings in COVID-19 patients is presented to enhance consistency in critical care decision making, and relevant infection control guidelines and operator precautions are discussed, based on a narrative review of the literature.

A review of COVID-19-related thrombosis and anticoagulation strategies specific to the Asian population.

The coronavirus disease 2019 (COVID-19) pandemic has placed an immense burden on healthcare systems worldwide. There is intensive research targeted at better understanding of the virus pathogenicity, development of effective treatment strategies and vaccines against COVID-19. It is increasingly being recognised that the pathogenicity of COVID-19 extends beyond the respiratory system. In severe cases, there can be widespread activation of the immune system, vascular injury and a resultant pro-thrombotic state. Severe COVID-19 is widely regarded as a risk factor for venous thromboembolism. Interim European and American guidelines have been created to guide anticoagulation strategies in COVID-19 patients. However, it is unclear if these guidelines can be extrapolated directly to Asians, in whom there are differences in the baseline risk of thrombosis and bleeding. Our review article aimed to summarise the current understanding of arteriovenous thromboembolic complications in COVID-19 and discuss management strategies for prevention and treatment of thrombotic events in Asian COVID-19 patients.

Shock due to an Obstructed Endotracheal Tube.

Endotracheal tube obstruction by a mucus plug causing a ball-valve effect is a rare but significant complication. The inability to pass a suction catheter through the endotracheal tube with high peak and plateau pressure differences are classical features of an endotracheal tube obstruction. A case is described of endotracheal tube obstruction from a mucus plug that compounded severe respiratory acidosis and hypotension in a patient who simultaneously had abdominal compartment syndrome. The mucus plug was not identified until a bronchoscopic assessment of the airway was performed. Due to the absence of classical signs, the delayed identification of the obstructing mucus plug exacerbated diagnostic confusion. It resulted in various treatments being trialed whilst the patient continued to deteriorate from the evasive offending culprit. We suggest that earlier and more routine use of bronchoscopy should be employed in an intensive care unit, especially as a definitive way to rule out endotracheal obstruction.

Is hypotensive anaesthesia guided by invasive intraarterial monitoring required for orthognathic surgery? - A retrospective review of anaesthetic practice and intraoperative blood loss in orthognathic surgery in a tertiary hospital.

BACKGROUND AND AIMS: Orthognathic surgeries for maxillofacial deformities are commonly performed globally and are associated with significant blood loss. This can distort the surgical field and necessitate blood transfusion with its concomitant risks. We aimed to review if invasive intraarterial (IA) line monitoring and/or hypotensive anaesthesia is required for orthognathic surgeries, and their effects on intraoperative blood loss and transfusion requirements. METHODS: This was a retrospective observational study conducted in patients admitted for orthognathic surgeries in a public tertiary hospital. Anaesthetic techniques and intraoperative haemodynamics were studied for their effects on intraoperative blood loss. RESULTS: The data from 269 patients who underwent orthognathic-bimaxillary surgeries was analysed. Inhalational anaesthetic combined with remifentanil was administered for 86.6%, total intravenous anesthesia to 11.2% patients, while the rest received inhalational anaesthesia. Hypotensive anaesthesia was achieved in 48 subjects (17.8%) and associated with shorter duration of surgery (349 vs 378 min, P = 0.02) and a trend towards lower blood loss (874 mL vs 1000 mL, P = 0.058) but higher transfusion requirement (81.3% vs 58.8%, P = 0.004). An IA line was used in 119 patients (44.2%) and was not associated with a higher probability of achieving hypotensive anaesthesia (19.3% vs 16.7%, P = 0.06). However, less blood loss (911 vs 1029 mL, P = 0.05) occurred compared to noninvasive blood pressure monitoring. CONCLUSION: Invasive blood pressure monitoring is as effective as noninvasive methods to achieve hypotensive anaesthesia. It does not aid in achieving lower target blood pressure. There is a lack of association between a reduction in blood loss and higher blood transfusion during hypotensive anaesthesiaand thiswill require further evaluation.

Sedation and Delirium in the Intensive Care Unit-A Practice-Based Approach.

INTRODUCTION: Critically ill patients often require sedation for comfort and to facilitate therapeutic interventions. Sedation practice guidelines provide an evidence-based framework with recommendations that can help improve key sedation-related outcomes. MATERIALS AND METHODS: We conducted a narrative review of current guidelines and recent trials on sedation. RESULTS: From a practice perspective, current guidelines share many limitations including lack of consensus on the definition of light sedation, optimal frequency of sedation assessment, optimal timing for light sedation and consideration of combinations of sedatives. We proposed several strategies to address these limitations and improve outcomes: 1) early light sedation within the first 48 hours with time-weighted monitoring (overall time spent in light sedation in the first 48 hours-sedation intensity-has a dose-dependent relationship with mortality risk, delirium and time to extubation); 2) provision of analgesia with minimal or no sedation where possible; 3) a goal-directed and balanced multimodal approach that combines the benefits of different agents and minimise their side effects; 4) use of dexmedetomidine and atypical antipsychotics as a sedative-sparing strategy to reduce weaning-related agitation, shorten ventilation time and accelerate physical and cognitive rehabilitation; and 5) a bundled approach to sedation that provides a framework to improve relevant clinical outcomes. CONCLUSION: More effort is required to develop a practical, time-weighted sedation scoring system. Emphasis on a balanced, multimodal appraoch that targets light sedation from the early phase of acute critical illness is important to achieve optimal sedation, lower mortality, shorten time on ventilator and reduce delirium.

Acute unilateral submandibular gland swelling associated with the laryngeal mask airway

We describe a rare complication of acute unilateral submandibular gland swelling following the use of laryngeal mask airway (LMA) in two patients with otherwise uneventful perioperative airway management. This is likely to be a consequence of the pressure exerted by the airway cuff on the tissues within the submandibular triangle. As this complication is rarely reported, its true incidence may in fact be higher, suggesting a need for greater attention on LMA cuff pressures and degree of cuff inflation. We discuss the presenting clinical features, pathophysiology and utilisation of ultrasonographic confirmation of sialadenopathy, and review the current anaesthetic literature to raise awareness of this unusual and under-reported complication of LMA. This complication can be mitigated by incorporating routine manometric checks and limiting intracuff pressures to < 60 cmH2O, potentially avoiding LMA insertions in patients with sialolithiasis and avoiding the use of nitrous oxide.