Effects of resuscitation with polymerized porcine hemoglobin (pPolyHb) on hemodynamic stability and oxygen delivery in a rat model of hemorrhagic shock

Figures & data

Figure 1. Life-sustaining ability of various resuscitation fluids in a rat hemorrhagic shock model. Rats hemorrhaged 65% of their total blood volume, and then each group (n = 8) received different resuscitation fluids: 1.5 g/kg pPolyHb, 0.6% hetastarch (HES), whole blood (WB), or normal saline (NS), plus twice the lost blood volume of NS. Survival was determined at 1 d intervals starting from the end of infusion of resuscitation fluids.

Table 1. Demographic data and survival times in different groups.

Measurement	pPolyHb	WB	HES	Saline
Number of animals	n = 8	n = 8	n = 8	n = 8
Weight (kg)	0.195 ± 0.015	0.205 ± 0.027	0.206 ± 0.012	0.214 ± 0.019
Hemorrhage (mL)	9 ± 0.9	9.4 ± 1.46	9.25 ± 1.2	9.67 ± 1.3
Hemorrhage (% wt)	66 ± 8	66 ± 6	64 ± 7	64 ± 5
Survivors/total	8/8	7/8	5/8	0/8
Minimum survival time (h)	−	3	12	3.5

Figure 2. Blood pressure and heart rate in rat hemorrhagic shock model. (A) Mean arterial blood pressure (MAP) and (B) heart rate (HR) were monitored every 10 min throughout the experiment. R: resuscitation. *p < 0.05 in comparison with baseline; #p < 0.05 in comparison with the pPolyHb group; $p < 0.05 in comparison with the WB group.

Table 2. Baseline blood gas parameters in different groups.

Parameter	pPolyHb	WB	HES	Saline
MAP (mmHg)	118.928 ± 4.364	119.705 ± 4.556	117.567 ± 4.666	118.442 ± 4.576
HR (bpm)	445 ± 16.823	443 ± 16.849	443 ± 15.767	446 ± 17.515
Lactate (mmol/L)	1.835 ± 0.516	1.830 ± 0.513	1.841 ± 0.514	1.838 ± 0.512
pH	7.391 ± 0.038	7.390 ± 0.032	7.391 ± 0.043	7.392 ± 0.04
BE (mmol/L)	−1.042 ± 1.766	−1.019 ± 1.784	−1.028 ± 1.756	−1.056 ± 1.781
HCO3^− (mmol/L)	22.262 ± 1.986	22.232 ± 1.936	21.762 ± 2.012	22.061 ± 1.902
PaCO2 (mmHg)	37.437 ± 1.559	36.863 ± 1.486	36.112 ± 1.628	36.063 ± 1.893
PaO2 (mmHg)	100.912 ± 5.906	100.823 ± 5.978	99.933 ± 6.007	99.897 ± 6.142

Figure 3. Lactate, base excess (BE), HCO₃⁻, and pH values in hemorrhagic shock model rats. Blood samples were drawn before the start of hemorrhage (baseline), end of shock and end of resuscitation to assess anaerobic metabolism. Blood gas analysis was performed on an ABL 800 (Radiometer, Copenhagen, Denmark). *p < 0.05 in comparison with baseline; #p < 0.05 in comparison with the pPolyHb group; $p < 0.05 in comparison with the WB group. (A) Lactate levels at different periods in rats resuscitated with pPolyHb, WB, HES, or saline. (B) BE levels at different periods in rats resuscitated with pPolyHb, WB, HES, or saline. (C) HCO3 levels at different periods in rats resuscitated with pPolyHb, WB, HES, or saline. (D) pH values at different periods in rats resuscitated with pPolyHb, WB, HES, or saline.

Figure 4. PaO₂ and PaCO₂ levels in hemorrhagic shock model rats. Blood samples were drawn before the start of hemorrhage (baseline), end of shock, and end of resuscitation to test PaO₂ and PaCO₂ levels. Blood gas analysis was performed on an ABL 800 (Radiometer, Copenhagen, Denmark). *p < 0.05 in comparison with baseline; #p < 0.05 in comparison with the pPolyHb group; $p < 0.05 in comparison with the WB group. (A) PaO₂ levels at different periods in rats resuscitated with pPolyHb, WB, HES, or saline. (B) PaCO₂ levels at different periods in rats resuscitated with pPolyHb, WB, HES, or saline.