PLASMA SUBSTITUTES 



79 



maintained the blood volume at 90 % at 24 hours. Six 

 per cent acacia produced the same effect. Three per 

 cent acacia maintained the blood volume at 85 % of 

 control at 24 hours. Handford and associates (45) 

 bled dogs a volume of blood equivalent to 5 % of 

 body weight and then infused an equal volume of 

 pectin as 4% glycerol pectate. The blood pressure re- 

 turned to control levels and was maintained, but 

 fell slowly over a 24-hour period. The plasma volume 

 was expanded and remained expanded for 12 hours. 

 Taylor & Waters (102) showed that 7% isinglass in 

 0.9% saline was capable of restoring blood pressure 

 in bled animals and permitted an increased per- 

 centage of recovery from otherwise fatal bleeding in 

 dogs. Ivy and associates (57) found only a slight 

 improvement in death rate of bled dogs when the 

 volume of blood removed was replaced with 5% 

 gelatin instead of normal saline. 



CLINICAL USES AND EFFECTS OF PLASMA SirBSTITUTES 



We should now like to consider the effects of plasma 

 substitutes in human subjects suffering from various 

 types of shock. Bayliss (8) used 3 "-"c or 6 % gum arable 

 in saline in wound shock. His patients appeared to 

 respond well to this. Those who did not respond also 

 failed to respond to subsequent blood infusions. Bayliss 

 stated that one must use a colloid to maintain blood 

 volume. Gelatin was said to be objectionable because 

 it may contain tetanus spores and may cause intra- 

 vascular clotting. He found no evidence of hemolysis, 

 red cell agglutination, or increased blood viscosity 

 with gum arable. Gum arabic in amounts equal to 

 half the whole blood volume was stated to be 

 innocuous. Figueroa & Lavieri (28) used i ':"(' grape- 

 fruit pectin in dogs shocked by intestinal massage 

 and found that the onset of shock was delayed as com- 

 pared to saline-treated controls. Five patients received 

 350 to 1000 ml of o.75'^7 pectin. The blood pressure 

 rose if low, but there was no immediate or delayed 

 reaction. The blood volume at 4 hours was increased 

 to a degree comparable to the amount infused. After 

 20 hours the blood volume was still slightly increased. 

 Jacobson & Smyth (60) used 5 % osseous gelatin in 

 isotonic sodium chloride (Upjohn). Fifty injections 

 were gixen to patients in shock. The response in 

 shock was satisfactory and no sensitivity was seen 

 when the injections were repeated. In three patients, 

 in whom postmortems were performed, no tissue 

 changes were seen. No reactions or urinary changes 

 were seen. Blood amino acids did not change and the 



authors thought that gelatin was probably not me- 

 tabolized. Popper and associates (85) used 5% gelatin, 

 average molecular weight 35,000, in saline and dex- 

 trose, and used pectin in saline with a molecular 

 weight of 45,000 to 60,000 in their studies. Both 

 substances produced hemodilution, which was more 

 pronounced in shock patients. One liter of gelatin 

 lowered the hematocrit an average of 11.6% in con- 

 trols and 19.5 "Tc in shock patients. Pectin lowered 

 the hematocrit an average of 10.3% in controls and 

 18.8% in shock patients. Both increased the sedi- 

 mentation rate of erythrocytes. The authors con- 

 cluded that the hemodynamic effects of the two 

 substances were similar, but tissue changes after pectin 

 caused them to prefer gelatin. Strumia and associates 

 (99) treated 15 patients with shock with modified 

 globin, average molecular weight 34,000, in 0.85% 

 saline. All patients treated responded satisfactorily. 

 Artz and associates (6) gave 4000 units of dextran to 

 2000 battle casualties. No urticaria, bronchospasm, 

 vasomotor instability, or untoward bleeding was ob- 

 served. The dextran employed was made by Com- 

 mercial Solvents Corporation, and was of average 

 molecular weight 43,000 to 48,000. Early effective 

 resuscitation was accomplished when blood loss was 

 20 to 30 % of estimated blood volume. Blood was 

 usually required in addition if the loss was equal to 

 35% of blood volume. These authors stated that 25% 

 depression of hematocrit by dextran seemed to be the 

 lower limit of safety. Freezing did not impair the 

 effectiveness of dextran. Also, modified fluid gelatin 

 was used in 200 units of 500 ml each. The gelatin had 

 an average molecular weight of 34,000. As much as 

 3000 ml of gelatin were recei\ed by some wounded 

 soldiers. The circulation was supported for the period 

 of evacuation, which was 3.5 hours, and no toxicity 

 was observed. In some patients 2000 ml of dextran 

 was given before and during wound debridement. The 

 authors felt that blood should be added if over 1 500 

 ml of plasma expander was required. Ohlke & Scales 

 (82) used dextran in 56 surgical cases, and PVP 

 (3.5 "i^ Subtosan) in 60 surgical cases. None of these 

 had reactions, and the majority had a good blood 

 pressure response. These writers found that the blood 

 pressure rose to expected levels if low, or did not fall 

 when the expanders were given prophylactically. 

 Weil & W'ebster (112) used dextran and Subtosan 

 P\'P in patients with blood loss. These agents were 

 able to maintain or restore blood pressure in in- 

 stances where blood loss did not exceed 1000 ml. No 

 allergic or pyrogenic or other reactions were seen. No 

 remote complications were seen, and there was no 



