Heart rate and arterial pressure changes during whole-body deep hypothermia

Whole-body deep hypothermia (DH) could be a new therapeutic strategy for asphyxiated newborn. This retrospective study describes how DH modified the heart rate and arterial blood pressure if compared to mild hypothermia (MH). Fourteen in DH and 17 in MH were cooled within the first six hours of life and for the following 72 hours. Hypothermia criteria were gestational age 6536 weeks; birth weight 651800\u2009g; clinical signs of moderate/severe hypoxic-ischemic encephalopathy. Rewarming was obtained in the following 6-12 hours (0.5\ub0C/h) after cooling. Heart rates were the same between the two groups; there was statistically significant difference at the beginning of hypothermia and during rewarming. Three babies in the DH group and 2 in the MH group showed HR 520\u2009ms. Infant submitted to deep hypothermia had not bradycardia or Qtc elongation before cooling and after rewarming. Blood pressure was significantly lower in DH compared to MH during the cooling, and peculiar was the hypotension during rewarming in DH group. Conclusion. The deeper hypothermia is a safe and feasible, only if it is performed by a well-trained team. DH should only be associated with a clinical trial and prospective randomized trials to validate its us

"Combined Helium and Combustion Gas Turbine Plant Exploiting Liquid Hydrogen (LH2) Physical Exergy",

The aim of this work is the energy and exergy analysis of a combined plant made up of a conventional gas turbine (heavy-duty or aeroderivative) and a closed helium turbine cycle which exploits liquid hydrogen (LH2) as a lower exergy source. A helium turbine with the characteristics of the fluid allows us to operate between the usual temperatures of the top turbine waste gas and those of the liquid hydrogen available. In this way the combined system reaches efficiency values greater than every combined system proposed to date. The work contains a detailed analysis of the relative entropy productions of the helium cycle and considerations about the realization and technological aspects of helium turbines.</jats:p