Effekte stromafreier Hämoglobinlösungen auf die Mikrozirkulation im quergestreiften Rückenhautmuskel beim Hamster
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vor 22 Jahren
Effects of stroma free hemoglobin solutions on microcirculation in
the striated dorsal skin muscle of the hamster: Since ischemia and
hypoxia lead to cellular necrosis by failure of microvascular
perfusion, oxygen delivery to the tissue is crucial for survival of
the organism. For decades there was pursuit of developing oxygen
carrying blood substitutes, but the breakthrough of stroma free
hemoglobin solutions has failed due to different issues such as
nephrotoxicity, systemic activation of complement cascade,
vasoconstriction and other side effects. To prove the in vivo
safety and efficiency of the solutions available to date,
quantitative analysis of the microcirculation is needed as a
crucial parameter of tissue integrity. In the present study, the
skin fold chamber model of the hamster was used to investigate the
effects of bovine and human hemoglobin solutions on the
microcirculation of the striated dorsal skin muscle by means of
computer assisted microcirculation analysis. This was done under
physiologic conditions by a hypervolemic infusion of appr. 10 % of
the calculated blood volume, and by an isovolemic hemodilution to a
hematocrit of appr. 25 %, respectively. For pathophysiologic
conditions a hemorrhagic shock as a stress model was induced by
non-fractioned withdrawal of half the calculated blood volume
within a few minutes, and treated by volume substitution with the
respective solutions. Our results demonstrate that the application
of the investigated hemoglobin solutions under physiologic
conditions does not impair the microcirculation. Under
pathophysiologic conditions they lead to an improved recovery of
blood flow as compared to common volume substitutes. However, the
level of tissue perfusion provided by retransfusion of autologous
blood was not achieved by treatment with the hemoglobin solutions.
Nevertheless, a sufficient tissue oxygenation was warranted by the
specific properties of the hemoglobin solutions. In clinical trials
the studied hemoglobin solutions were effective in elective surgery
with expected major blood loss but not in trauma patients. The
development of an oxygen carrying blood substitute suitable for
trauma patients is still being pursued.
the striated dorsal skin muscle of the hamster: Since ischemia and
hypoxia lead to cellular necrosis by failure of microvascular
perfusion, oxygen delivery to the tissue is crucial for survival of
the organism. For decades there was pursuit of developing oxygen
carrying blood substitutes, but the breakthrough of stroma free
hemoglobin solutions has failed due to different issues such as
nephrotoxicity, systemic activation of complement cascade,
vasoconstriction and other side effects. To prove the in vivo
safety and efficiency of the solutions available to date,
quantitative analysis of the microcirculation is needed as a
crucial parameter of tissue integrity. In the present study, the
skin fold chamber model of the hamster was used to investigate the
effects of bovine and human hemoglobin solutions on the
microcirculation of the striated dorsal skin muscle by means of
computer assisted microcirculation analysis. This was done under
physiologic conditions by a hypervolemic infusion of appr. 10 % of
the calculated blood volume, and by an isovolemic hemodilution to a
hematocrit of appr. 25 %, respectively. For pathophysiologic
conditions a hemorrhagic shock as a stress model was induced by
non-fractioned withdrawal of half the calculated blood volume
within a few minutes, and treated by volume substitution with the
respective solutions. Our results demonstrate that the application
of the investigated hemoglobin solutions under physiologic
conditions does not impair the microcirculation. Under
pathophysiologic conditions they lead to an improved recovery of
blood flow as compared to common volume substitutes. However, the
level of tissue perfusion provided by retransfusion of autologous
blood was not achieved by treatment with the hemoglobin solutions.
Nevertheless, a sufficient tissue oxygenation was warranted by the
specific properties of the hemoglobin solutions. In clinical trials
the studied hemoglobin solutions were effective in elective surgery
with expected major blood loss but not in trauma patients. The
development of an oxygen carrying blood substitute suitable for
trauma patients is still being pursued.
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