Effect of heating in a calorstat to the oxygen-carrying function of red blood cell / 临床麻醉学杂志

Objective To study the change of the oxygen-carried function of stored red blood cells,which was warmed in room temperature and calorstat.Methods Randomly removed from 4 ℃storage refrigerator,red blood cell suspension were put in room temperature 30 min (group N)and 37℃ calorstat 30 min (group H),and samples taken to examine electrolyte,blood gas,free Hb,ATP content,2,3-DPG content,oxygen affinity(P50).Results In two groups,blood pH value and blood Na+ did not change obviously due to heating.The content of blood K+ and free Hb increased,glucose fell,but there was no statistically significant difference.The content of ATP and 2,3-DPG in eryth-rocyte increased and P50 increased after heating (P <0.05),which increased more significantly in group H compared with group N (P<0.05).Conclusion Heating stored blood up to 37 ℃ can in-crease the oxygen-carried function of red blood cells,which contribute to improve the effectiveness of transfusion.

Optimized hyperventilation preserves 2,3-diphosphoglycerate in severe traumatic brain injury

INTRODUCTION: The concentration of 2,3-diphosphoglycerate (2,3-DPG/Hct) increases as a physiological occurrence to pH increase and hyperventilation. This response was tested in patients with severe traumatic brain injury (TBI). METHOD: The concentration of 2,3-DPG/Hct was measured daily for six days in eleven patients with severe TBI in need of optimized hyperventilation because of intracranial hypertension. RESULTS:There was correlation between pH and the concentration of DPG/Hct. The concentration of 2,3-DPG/Hct remained predominantly within normal levels with slight increase in the sixth day of the study. The concentration of 2,3-DPG/Hct correlated significantly with measured partial pressure of oxygen that saturates 50 percent the hemoglobin of the blood (P50st), confirming the consistency of our data. CONCLUSION: The expected physiological response of a progressive increase in concentration of 2,3-DPG/Hct to hyperventilation was not observed. This fact may be explained by the intermittent and not sustained hyperventilation as dictated by the protocol of optimized ventilation.

INTRODUÇÃO: A concentração de 2,3-difosfoglicerato nos eritrócitos (2,3-DPG/Hct) aumenta como ocorrência fisiológica ao aumento do pH e à hiperventilação. Esta resposta foi testada em pacientes com traumatismo craniencefálico (TCE) grave. MÉTODO: A concentração de 2,3-DPG/Hct foi medida diariamente, durante seis dias, em 11 pacientes com TCE grave necessitando de hiperventilação otimizada por causa da hipertensão intracraniana. RESULTADOS: Houve correlação entre o pH e a concentração de 2,3-DPG/Hct. A concentração de 2,3-DPG/Hct permaneceu predominantemente dentro da normalidade, com ligeira tendência à elevação no sexto dia de estudo. Houve correlação entre a concentração de 2,3-DPG/Hct e a pressão parcial de oxigênio que satura 50 por cento da hemoglobina (P50st), confirmando a consistência dos dados. CONCLUSÃO: A esperada resposta fisiológica de aumento progressivo da concentração de 2,3-DPG/Hct não foi observada. Este fato pode ser explicado pela aplicação intermitente e não sustentada de hiperventilação, como ditado pelo protocolo clínico de ventilação otimizada.

The Erythrocyte 2,3-diphosphoglycerate Concentration and Its Related Factors in Patients with End-stage Liver Disease / 대한마취과학회지

BACKGROUND: It is believed that an increase in the level of erythrocyte 2,3-diphosphoglycerate is an important compensatory mechanism that allows satisfactory tissue oxygenation in hypoxic patients. This study measured the level of 2,3-diphophoglycerate and the factors affecting its concentration, as well as the position of the oxygen-hemoglobin dissociation curve in patients with end-stage liver disease. METHODS: Fifty patients receiving liver transplantation (experimental group) and forty-five healthy donors (control group) were enrolled in this study. Arterial-mixed venous oxygen content difference, whole body oxygen delivery and consumption were measured after determining the hemodynamic parameters including cardiac output in the experimental group. The erythrocyte 2,3-diphosphoglycerate level was measured using assay procedures. The P50 value was used to determine the position of the oxygen-hemoglobin dissociation curve. RESULTS: The 2,3-diphosphoglycerate level was higher in patients with end-stage liver disease than in the controls. A 0.3 g/L increase in the 2,3-diphosphoglycerate concentration corresponded to a P50 increase in 1.2 mmHg with a rightward displacement of the oxygen-hemoglobin dissociation curve. The 2,3-diphosphoglycerate concentration showed a significant correlation with the PaO2, Ca-vO2, P50, and blood lactate level, but not with the hemodynamic parameters such as the cardiac index, oxygen delivery index, and pH. CONCLUSIONS: End-stage liver disease is associated with an increase in the level of the erythrocyte 2,3-diphosphoglycerate and P50. This is believed to be an important compensatory mechanism to allow better tissue oxygenation. An increase in the 2,3-diphosphoglycerate level correlates well with the oxygenation parameters, rather than with the hemodynamic parameters.

Combined stress of low environmental pressure and temperature on sodium and potassium homeostasis in rat blood.

Adult rats were subjected to the combined stress of low atmospheric pressure and temperature at a simulated altitude of 7620 metres and at 5°C for 5 hours. A significant increase in the influx of rubidium-86 and the efflux of sodium-22 was observed in erythrocytes of experimental rats in vitro. Blood 2,3-diphosphoglycerate was appreciably enhanced while blood sodium and reduced glutathione contents in the experimental animals remained unchanged.