Ultrasound assessment of gastric contents in children before general anaesthesia for acute appendicitis.

There is increasing evidence that a minority of adults with acute appendicitis have gastric contents, posing an increased risk of pulmonary aspiration. This study aimed to evaluate the proportion of children with acute appendicitis who have gastric contents considered to pose a higher risk of pulmonary aspiration. We analysed point-of-care gastric ultrasound data routinely collected in children before emergency appendicectomy in a specialist paediatric hospital over a 30-month period. Based on qualitative and quantitative antral assessment in the supine and right lateral decubitus positions, gastric contents were classified as 'higher-risk' (clear liquid with calculated gastric fluid volume > 0.8 ml.kg-1 , thick liquid or solid) or 'lower-risk' of pulmonary aspiration. The 115 children studied had a mean (SD) age of 11 (3) years; 37 (32%; 95%CI: 24-42%) presented with higher-risk gastric contents, including 15 (13%; 95%CI: 8-21%) with solid/thick liquid contents. Gastric contents could not be determined in 13 children as ultrasound examination was not feasible in the right lateral decubitus position. No cases of pulmonary aspiration occurred. This study shows that gastric ultrasound is feasible in children before emergency appendicectomy. This technique showed a range of gastric content measurements, which could contribute towards defining the risk of pulmonary aspiration.

Gas embolism produced by hydrogen peroxide abscess irrigation in an infant.

The production of gaseous oxygen when hydrogen peroxide interacts with tissue is a well-known phenomenon that has been reported as a rare cause of gas embolism. We present the case of an 11-month-old infant who sustained an immediate cardiorespiratory arrest following the use of this agent during a minor surgical procedure. Clinical features, radiological findings and the rapid response to resuscitation were strongly suggestive of major gas embolism. Adverse effects of inappropriate use of hydrogen peroxide, and the diagnosis and management of these problems are discussed.

Mediastinal mass obscured by a large pericardial effusion in a child: a potential cause of serious anaesthetic morbidity.

Anaesthesia in the presence of a mediastinal mass is known to be hazardous. We report a case of a 5-year-old boy with a presumed postviral pericardial effusion presenting for pericardiocentesis under general anaesthesia. Cardiorespiratory collapse following induction of anaesthesia occurred due to an undiagnosed mediastinal tumour. The reasons for misdiagnosis, mechanisms for perioperative complications and optimal management are discussed. Mediastinal masses and underlying malignancy should always be considered in patients with large pericardial effusions.