CARDIOGENIC MIXING: MECHANISMS AND EXPERIMENTAL EVIDENCE IN DOGS

Cardiogenic mixing was studied in seven anaesthetized closed-chestdogs undergoing mechanical ventilation by comparing single-breathwashout of two poorly soluble inert gases of widely differingdiffusivities (helium (He) and sulphur hexafluoride (SFg)) innormal conditions with the heart beating (control), and duringreversible temporary myocardial arrest (heart arrest). Cardiacarrest of approximately 20 s duration was induced repeatedly(8–15 times) by intracoronary injection of acetylcholine(approximately 35 mg) facilitated by a non-occluding 7–Frenchgauge angiographic catheter maintained in the left coronaryartery. After equilibration of lung gas with 1 % helium and1 % SFg, single breath, constant flow expirograms were recordedin the trachea! tube by mass spectrometry after inspirationof test gas-free air. Series deadspace (Vd) and relative alveolarslope (S) increment of expired partial pressure, normalizedto mixed expired-inspired partial pressure difference per incrementof expired volume (S = {AI{e–i)}IAVe litre–1)),were determined as indices for intrapulmonary gas mixing. Theeffects attributable to the action of the heart were quantifiedby the heart arrest: control ratio of Vd and S, which were notsignificantly different from unity (P > 0.05) (Vd: 0.95 (SD0.05) for helium and 0.94 (0.07) for SFS;S: 1.03 (O.1O) forhelium and 1.05 (0.14) for SFg. The He:SFs ratios of Vd andS (0.90 and 0.64, respectively), indicating diffusion dependentseparation of gases, also were unaffected by the mechanicalaction of the heart. The data indicate that convective mixingby the mechanical action of the heart did not significantlyenhance intrapulmonary mixing and transport.     

The effects of patient suicide on nursing staff

• ? Attitudes towards patient suicide, and the effects that this has on nursing staff are rather complex, and should not be viewed on a simple negative/positive continuum.
• ? Suicide is a difficult but inevitable incident that affects psychiatric units, and the limited literature on nurses' attitudes to suicide, and the effects that patient suicide has on them has highlighted the need for emotional and professional support from their colleagues, including senior nurses, psychiatrists and managers, to cope better after a patient has committed suicide. Furthermore, the importance of regular meetings and reviews of assessment and prevention policies has also been emphasized.
• ? The present study looked at the effects that suicide has on nursing staff, their attitudes, and ways of improving their coping skills. Major findings include the lack of emotional support, the need for training, formal assessment of patients at risk, regular multidisciplinary meetings following a suicide and nursing staff's acceptance of suicide as the patient's personal choice.
• ? Recommendations for helping nursing staff during the post-suicide period are suggested.

     

Did the role of the neurologist in the emergency department change during the COVID-19 pandemic? Evidence from an Italian nationwide survey

Neurological Sciences - This study aims to assess whether the role of neurologists in the emergency department changed during the coronavirus (COVID)-19 pandemic. Data from an Italian national...