Suicide by helium inhalation in the Netherlands between 2012 and 2019.

INTRODUCTION: In 2012 and 2013 a movie and a book about a 'dignified end of life' were published in the Netherlands. These items described suicide using an 'exit bag' to establish asphyxiation using helium (the helium method). 'Right-to-die-organisations' inform the elderly about this method. The purpose of this study is to investigate whether the use of suicidal asphyxiation by means of the helium method substituted other, related, methods following its publication in the Netherlands. MATERIAL AND METHODS: We analysed suicides in the Netherlands over the period from 1 July 2012 to 30 June 2019. We compared the number of deaths caused by the helium method with other, related, cases. Secondly, we related these deaths to the total number of inhabitants and suicides recorded by Statistics Netherlands. RESULTS: The study showed a stable trend in the use of the helium method in the period 2012-2019 and this was the same for the other, related methods. Individuals using the helium method were significantly younger than those using other, related, methods. At the scene of death, information about suicide and suicide notes were found more often at 'helium method' cases than with the 'other, related, methods' cases. Family was significantly more often present during a helium method suicide than during suicide by other, related, methods. DISCUSSION: The number of suicides by the helium method and other, related, cases is stable in the Netherlands over the past years. Therefore, we conclude that there is no substitution effect within this category of suicides. Whilst 'right-to-die-organisations' strive to inform the old and sick of the helium method, it is noteworthy that the individuals using the helium method are significantly younger than the individuals who choose other, related, methods.

Commonly used numbers of microspheres affect cardiac vascular resistance.

The main goal of the study was to examine how the microsphere technique affects the hemodynamics and mitochondrial energy status of the Langendorff-perfused rat heart. The hearts were perfused at a constant flow with Tyrode solution. NADH videofluorometry of the surface of the left ventricle was used to record the mitochondrial energy status as indication of regional ischemia. The effects of seven successive (separated by 10 min) injections of 0.1 ml of saline or (0.05% Tween 20; polysorbate 20, Sigma-Aldrich, St. Louis, MO, U.S.A.) or (0.05% Tween 20 + microspheres) were studied. The number of microspheres per injection were: #1 (2,500), #2 (5,000), #3 (10,000), #4 (20,000), #5 (40,000), #6 (40000), and #7 (80000). The anti-aggregation agent Tween always caused a biphasic response in perfusion pressure. Compared with the Tween effect, the injection of microspheres caused an initial change (mm Hg) in perfusion pressure of #1 (-10), #2 (NS), #3 (NS), #4 (+7.5), #5 (+12.3), #6 (+14.4), #7 (+18.3), and a delayed change (10 min after injection) of #1 (-22.2), #2 (-6.0), #3 (-4.1), #4 (-4.5), #5 (NS), #6 (NS), and #7 (+5.9). The microspheres caused a significant delayed increase in NADH only for injection #6 and #7. Similar results were found for different durations of the input function or when hearts were perfused at constant perfusion pressure. In hearts without flow reserve (10 microM adenosine), Tween injections were without effect, whereas three successive injections of 60,000 microspheres each only caused increases in perfusion pressure and NADH. The data demonstrate that in hearts with flow reserve present, even very low numbers of microspheres (2,000/g heart) cause large decreases in perfusion pressure without obvious signs of ischemia. When flow reserve was exhausted by either microsphere loading or adenosine addition, microspheres only caused increases in perfusion pressure and resulted in detectable ischemia (NADH). It is concluded that microspheres affect the vascular resistance of the heart and that these effects are flow reserve dependent.