Nitrous oxide-induced myeloneuropathy: an emerging public health issue.

Increasing use of nitrous oxide as a recreational drug has been reported among young adults in western countries over the past decade. We present two cases of young males presenting to the Emergency Department (ED) of a large urban university hospital in Dublin with progressive neurological dysfunction related to nitrous oxide use. We review the pathophysiology, clinical features and treatment of nitrous oxide neurotoxicity. It is important that clinicians are aware of this evolving public health issue and are able to recognize the clinical features of this rare presentation, which may become more common in Irish EDs and GP surgeries as nitrous oxide abuse becomes more prevalent.

Intravascular lithotripsy-assisted PCI for severely calcified coronary lesions: evaluating the impact on quality of life and outcomes.

BACKGROUND: Despite the increased uptake of intravascular lithotripsy (IVL) for treating severely calcified coronary lesions, there is limited patient-level data examining the effect of IVL on quality of life, symptomatology, and outcomes beyond 30 days. We sought to assess demographics, procedural characteristics, outcomes, and impact of IVL on patient-reported angina after a minimum of 6 months follow-up. METHODS: A retrospective single-center study was conducted of patients treated with coronary IVL between January and October 2020. Baseline demographics were obtained from electronic patient records and SYNTAX scores were calculated from index coronary angiograms. Technical success and complications were assessed along with clinical outcomes, which included all-cause mortality, myocardial infarction (MI), target lesion revascularization (TLR), and MACE (composite of death, stroke, MI, and TLR). Canadian Cardiovascular Society (CCS) angina classification was assessed at virtual clinical follow-up. RESULTS: Forty-seven consecutive patients were included. At a mean follow-up of 306 ± 74 days, the mean CCS angina score was reduced by 53% post-IVL-assisted PCI (2.9 vs 1.4, p < 0.001). Technical and procedural success were high (94% and 92%, respectively). One patient (2%) met the pre-specified criteria for in-hospital MACE and 4 (9%) met pre-specified MACE at follow-up, including 2 deaths and 2 TLR. Procedural complications included coronary dissection (11%) and coronary perforation (6%) and were managed either conservatively or with PCI. CONCLUSIONS: Coronary IVL is a safe and effective adjunctive therapy for treating heavily calcified coronary lesions. This cohort shows high procedural success and a significant reduction in CCS angina at follow-up.

Increasing radiation exposure from computed tomography in liver transplant recipients over time.

OBJECTIVES: To evaluate changes in radiation exposure from computed tomography (CT) among patients undergoing liver transplantation in our unit over a 10-year period. METHODS: We evaluated 134 elective patients, without hepatocellular carcinoma or cholangiocarcinoma who underwent transplantation in 2007-2008 and 2017-2018. CT scans performed in our hospital up to 2 years pre transplant and 1 year post transplant were evaluated. RESULTS: There was an increase in mean estimated effective radiation dose per patient in 2017-2018 compared to 2007-2008 (77.8 mSv ± 6.2 vs 56.7 mSv ± 5.9, p < 0.05). This change was mainly due to an increased number of pre-transplant CT scans per patient (2.9 ± 0.3 vs 1.4 ± 0.14, p = 0.0001). High radiation dose scan protocols were more frequently used in 2017-2018, with 4-phase liver CT accounting for a larger proportion of scans both pre-transplant (61% vs 43%, p = 0.004) and post-transplant (29% vs 13%, p = 0.002). A greater proportion of patients were exposed to > 100 mSv of ionising radiation in the 2017-2018 patients (29% vs 11%, p < 0.01). These figures are likely to be a significant under-estimate as they exclude other imaging modalities and CT scans performed at other institutions. CONCLUSION: Radiation exposure from diagnostic imaging has increased among liver transplant recipients at our institution over the last decade. This appears to be due to an increase in the number of CT scans performed, and a shift towards higher dose scan protocols.