Background Assessment of pulmonary embolism (PE) remains a diagnostic and investigative burden to emergency departments. The decision of which D‐dimer cut‐off to use in low‐risk patients remains controversial. Aims To compare the sensitivity and specificity of varying D‐dimer cut‐offs in the diagnosis of PE for Wells low‐risk patients. Methods Retrospective review of patients presenting to a tertiary emergency department over 42 months who had a D‐dimer performed for PE risk stratification. Wells scores were calculated for each patient, those with Wells score of ≤4 (‘PE unlikely’) were analysed. Four D‐dimer thresholds were compared, including traditional threshold (≥0.5 μg/mL), age‐adjusted (≥age in years × 0.01 μg/mL), doubled‐traditional threshold and YEARS criteria. Results During the study period, 2291 D‐dimers were ordered for suspected PE, of which 2125 were low risk for PE. Of these low‐risk patients 46 (2.2%) were found to have a PE. The sensitivity and specificity for each D‐dimer threshold were traditional threshold (95.6% and 65.6%), age‐adjusted (93.5% and 71.7%), doubled traditional (69.6% and 85.5%) and YEARS criteria (80.4% and 84.0%). Utilising an age‐adjusted threshold, YEARS criteria or doubled‐traditional threshold would have resulted in 70, 217 and 245 fewer imaging investigations. Conclusions The prevalence of PE in this low‐risk cohort was very low. Utilising an age‐adjusted D‐dimer would have reduced imaging tests performed while maintaining good sensitivity. Although The YEARS criteria and doubled‐traditional threshold would have reduced scanning considerably both had sensitivities of less than 90%.

Apneic oxygenation (ApOx) has shown to be effective in adult populations in a variety of settings, including prehospital, emergency departments, intensive care units, and elective surgery. This review aims to assess the available literature for ApOx in the pediatric population to determine its effects on hypoxemia, safe apnea times, and flow rates employed safely.

Introduction In lab-based studies, buprenorphine appears to have a ceiling effect on respiratory depression but not on analgesia. There is increasing evidence in adult patients that buprenorphine has no ceiling effect on analgesia or side effects. The aim of this study was to investigate the efficacy and adverse effects of buprenorphine versus morphine in paediatric acute pain. Methods A systematic review of five databases was performed until May 2018. Only randomised controlled trials were eligible for inclusion. The outcomes of interest included pain, respiratory depression, nausea, sedation, dizziness, and pruritus. Results Four randomised controlled trials (n=195) were included. The only outcome measuring analgesic efficacy was time to breakthrough analgesia. Buprenorphine had a significant increase in time to breakthrough analgesia by 114.98 minutes compared to morphine (95% CI = 42.94 to 187.01; I2 = 0; p=0.002). There was no significant difference in the rates of adverse effects. Conclusions Buprenorphine provided a longer duration of analgesia than morphine. This in combination with its unique sublingual preparation could prove particularly advantageous in the paediatric population. The studies included are likely underpowered to detect differences in the incidence of adverse effects; therefore, the same precautions should be taken as with any other opioid.