Polyhemoglobin Resuscitation in Guinea Pigs

Fully conscious, heparinized animals underwent 50% ET with PolyCHb solution (Hb concentration 6%, human albumin 4%; the PolyCHb and human albumin were mixed immediately before ET). The blood was collected through the arterial catheter, and the PolyCHb solution was transfused through the venous catheter by syringe pumps simultaneously at a rate of 1 mL/min. The total blood volume of a guinea pig was calculated as 0.07 (milliliters per gram) × body weight (grams) (Ancill, 1956 (link)). Immediately after ET, AA injection solution was injected to the body via the venous catheter, by a 1 mL disposable syringe. The dosage of AA is calculated by multiplying the target concentration (2 mmol/L) with the blood volume. Blood samples (300 μL) were obtained from the arterial catheter pre-transfusion together at 0 and 4 h after ET. The guinea pigs were individually housed in metabolism cages for 4 h pre- and post-ET to collect the urine samples. The animals were sacrificed 4 h post-ET and the kidneys were dissected and rinsed with pre-cold saline. One kidney was cut in half and frozen immediately in liquid nitrogen, and the other kidney was fixed in 10% paraformaldehyde.