The impact on renal function of fluid resuscitation with hemoglobin vesicle solution in moderate hemorrhagic shock.

In this study, hemoglobin vesicle (HbV), a type of artificial oxygen carrier, was infused in a hemorrhagic shock model, and the findings were compared with those of red blood cell (RBC) transfusion to evaluate the effects on blood pressure and renal function. In rats maintained in hemorrhagic shock for 30 min under general anesthesia, either irradiated stored RBCs from the same strain or HbVs were used for resuscitation. Blood pressure, serum creatinine concentration, and creatinine clearance 24 h after shock were measured. At 2 and 24 h after shock, the kidneys were removed, and the heme oxygenase-1 (HO-1) mRNA level was measured. A histopathology study was performed 24 h after shock. In both the RBC and HbV group, blood pressure recovered significantly immediately after fluid resuscitation, and blood pressure 24 h after shock did not differ significantly between the two groups. Serum creatinine concentration and creatinine clearance 24 h after shock did not differ significantly between the two groups. After 24 h, there was no significant difference in HO-1 mRNA between the groups. In the renal histopathology samples taken at 24 h after shock, there were no obvious differences between the two groups. In conclusion, HbV transfusion improved blood pressure in a manner equivalent to RBC transfusion when administered during hemorrhagic shock, and no renal dysfunction was apparent after 24 h.

Atrial natriuretic peptide alleviates cardiovascular and metabolic disorders in a rat endotoxemia model: a possible role for its anti-inflammatory properties.

BACKGROUND: Atrial natriuretic peptide (ANP) plays important roles in the regulation of cardiovascular and renal homeostasis. Furthermore, several studies have shown that ANP may have anti-inflammatory activities. We hypothesized that ANP may alleviate cardiovascular and/or metabolic disorders in rats with lipopolysaccharide (LPS)-induced endotoxemia. METHODS: In rats anesthetized with pentobarbital, LPS was injected and ANP was continuously infused at 0.15 µg/kg/min. Mean arterial pressure and pulse rate were monitored hourly, and arterial blood gases were analyzed before LPS injection and at 1, 4, and 6 hours after LPS injection. The expression in the rat left ventricle of mRNAs encoding nitric oxide synthase 2 and 3 (iNOS, eNOS), heme oxygenase 1 and 2 (HO-1, 2), tumor necrosis factor α (TNFα), and interleukin (IL)-1ß was measured with the real-time reverse transcriptase-polymerase chain reaction. RESULTS: LPS increased the expression of TNFα, IL-1ß, iNOS, and HO-1, which was inhibited by infusion of ANP. Furthermore, the LPS-induced decrease in mean arterial pressure was attenuated, and the acid-base imbalance caused by increased lactate production was improved 6 hours after the administration of ANP. CONCLUSIONS: Our results suggest that continuous infusion of ANP counteracts the cardiovascular and metabolic disorders associated with endotoxemia, possibly via anti-inflammatory mechanisms.

The reciprocal relationship between heme oxygenase and nitric oxide synthase in the organs of lipopolysaccharide-treated rodents.

The production of nitric oxide (NO) by inducible NO synthase (NOS) and carbon monoxide (CO) by inducible heme oxygenase (HO) contributes greatly to endotoxemia. Reciprocal relationships have been proposed between the NO/NOS and CO/HO systems. However, the interaction between these systems during endotoxemia is unclear, and it is unknown whether the interactive behavior differs among organs. Using endotoxic rats, we studied the effects of the inducible NOS (iNOS) inhibitor L-canavanine (CAN), and the HO inhibitor zinc protoporphyrin (ZPP) on gene expression and protein levels of iNOS, endothelial NOS (eNOS), inducible HO (HO-1), and constitutive HO (HO-2) in the brain, lung, heart, liver and kidney tissue. Intravenous injection of LPS significantly increased iNOS and HO-1 gene expression in all organs. The effects of LPS on eNOS gene expression differed among organs, with increased expression in the liver and kidney, and no change in the lung, brain and heart. ZPP administration down-regulated the LPS-induced increase in HO-1 expression and produced a further increase in iNOS expression in all organs. These data suggest that the CO/HO system modifies the NO/NOS system in endotoxic organs, and that there were only minor organ-specific behaviors in terms of the relationship between these systems in the organs examined.

A transient inflammatory reaction in the lung after experimental hemorrhagic shock and resuscitation with a hemoglobin-vesicles solution compared with rat RBC transfusion.

Transfusion for hemorrhagic shock can improve oxygenation, but immunoreactions may induce inflammation. Artificial oxygen carriers have been developed to address clinical concerns of infection and stability, but whether an artificial oxygen carrier might induce inflammation is not well known. To address this question, we compared inflammatory reactions after resuscitation with hemoglobin vesicles (HbVs) or red blood cells (RBCs) in a hemorrhagic shock rat model. Both HbVs and the stored and irradiated rat RBCs deprived of buffy coat were suspended in recombinant human serum albumin [(Hb) = 8.6 g/dL]. Under anesthesia, hemorrhagic shock was induced for 30 min, followed by resuscitation by 20 min transfusion of HbVs or rat RBCs in a volume equivalent to the volume of withdrawn blood. Lungs were excised 2 or 24 h after resuscitation, and mRNA levels of tumor necrosis factor alpha (TNF-alpha), intercellular adhesion molecule-1 (ICAM-1), nitric oxide synthase 2 (iNOS), nitric oxide synthase 3, hypoxia-inducible factor 1 alpha, and heme oxygenase 1 (HO-1) were measured. In rats resuscitated with HbVs, mRNA levels of TNF-alpha and HO-1 2 h after resuscitation were significantly higher than those in the rat RBC group, but the levels at 24 h were similar in both groups. The expression of iNOS and ICAM-1, second messengers of inflammation, was not affected, and inflammatory levels after 24 h with HbVs are similar to rat RBC transfusion. The rat RBC group did not show an expected inflammatory reaction related to a transfusion-induced lung injury, and a clinical relevance concerning this level of transient inflammatory reaction induced by HbVs is not known; however, attention to the early stage of resuscitation in ongoing studies of HbV is required.

[Anesthesia management for laparoscopic prostatectomy and open prostatectomy].

BACKGROUND: For anesthetic management of traditional open prostatectomy, preparation for hemorrhage is necessary. However, it has been considered that the amount of bleeding under laparoscopic prostatectomy is less than that of traditional open surgery. METHODS: The amount of bleeding and autologous blood preparation, fluid balance, and anesthetic management were investigated in patients who had undergone laparoscopic or open prostatectomy at the Nippon Medical School Hospital between June, 2004 and November, 2005, retrospectively. The difference of these aspects between the two surgical method groups was evaluated. RESULTS: Thirty-two patients underwent prostatectomy in the investigation period. In these patients, 4 patients were excluded due to incomplete anesthesia record or change of surgical method. The amount of bleeding, and both amount of autologous blood preparation and transfusion in the laparoscopic surgery were less than those in the open surgery. There were no significant differences in the fluid balance and amount of urine output between the two groups. CONCLUSIONS: We conclude that preparation of autologous blood transfusion is necessary for the traditional open prostatectomy, but not for the laparoscopic prostatectomy.