Recreational nitrous oxide and thrombotic events: a case series.

Background: The study aimed to elucidate the prevalence of nitrous oxide (N2O) usage in patients with unexplained venous thromboembolism (VTE), highlighting the potential association with hyperhomocysteinaemia (HHcy). Methods: We conducted a retrospective study at the Royal London Hospital, examining cases of N2O-related VTE from March to August 2023. Among 50 patients identified, four (8%) had recent unprovoked VTE. Patient data were collected based on N2O ambulatory emergency care pathway admissions. Results: Among the 50 patients identified, four (8%) had recent or concurrent VTE. Three were male (75%), with an ethnic distribution of 50% Asian or Asian British and 50% Black or Black British. Patients were distributed across quintiles of the index of multiple deprivation. All had actual or functional vitamin B12 deficiency. Discussion: The association between N2O use and VTE requires further investigation, though a plausible mechanism involving HHcy has been proposed. Clinicians should be vigilant for VTE in N2O users, especially those presenting with unexplained symptoms. VTE prophylaxis may be worth considering, particularly if continued exposure to nitrous oxide is anticipated. Conclusion: N2O misuse may increase the risk of VTE, warranting attention from healthcare providers. Further research is needed to elucidate this association and inform preventive strategies. Public awareness about the risks of N2O remains essential.

Predicting Length of Stay in Hospital Using Electronic Records Available at the Time of Admission.

Predicting a patient's hospital length of stay (LoS) can help manage staffing. In this paper, we explore LoS prediction for a large group of patients admitted non-electively. We use information available at admission, including demographics, acute and long-term diagnoses and physiological tests results. Data were extracted from the electronic health records (EHR), so that the LoS prediction would not require additional data entry. Although the data can be accessed, the system does not present a unified view of the data for one patient: to resolve this we designed a process of cleaning and combining data for each patient. The data was used to fit semi-parametric, parametric and competing outcomes survival models. All models performed similarly, with concordance of approximately 0.7. Calibration results showed underestimation of predicted discharges for patients with high discharge probabilities and overestimation of predicted discharges for those with low discharge probabilities. The main challenges in operationalizing LoS predictions are delays in entering admissions data into EHR and absent data about non-medical factors determining discharges.

Validation of interphase fluorescence in situ hybridization (iFISH) for multiple myeloma using CD138 positive cells.

BACKGROUND: Multiple myeloma is a plasma cell neoplasm with acquired genetic abnormalities of clinical and prognostic importance. Multiple myeloma differs from other hematologic malignancies due to a high fraction of low proliferating malignant plasma cells and the paucity of plasma cells in bone marrow aspiration samples, making cytogenetic analysis a challenge. An abnormal karyotype is found in only one-third of patients with multiple myeloma and interphase fluorescence in situ hybridization is the most useful test for studying the chromosomal abnormalities present in almost 90% of cases. However, it is necessary to study the genetic abnormalities in plasma cells after their identification or selection by morphology, immunophenotyping or sorting. Other challenges are the selection of the most informative FISH panel and determining cut-off levels for FISH probes. This study reports the validation of interphase fluorescence in situ hybridization using CD138 positive cells, according to proposed guidelines published by the European Myeloma Network (EMN) in 2012. METHOD: Bone marrow samples from patients with multiple myeloma were used to standardize a panel of five probes [1q amplification, 13q14 deletion, 17p deletion, t(4;14), and t(14;16)] in CD138(+) cells purified by magnetic cell sorting. RESULTS: This test was validated with a low turnaround time and good reproducibility. Five of six samples showed genetic abnormalities. Monosomy/deletion 13 plus t(4;14) were found in two cases. CONCLUSION: This technique together with magnetic cell sorting is effective and can be used in the routine laboratory practice. In addition, magnetic cell sorting provides a pure plasma cell population that allows other molecular and genomic studies.