CHAPTER 23 



Blood Grouping 



HISTORICAL REVIEW THE RH FACTOR 



Significance in multiple transfusions 

 BLOOD TRANSFUSIONS Significance in pregnancy 



Typing of blood 

 Cross matching of blood QUESTIONS OF DISPUTED PARENTAGE 



HISTORICAL REVIEW 



Some readers may question the inclusion of a chapter on blood 

 grouping in a book of this nature. Since serological reactions are 

 involved in these blood determinations, and since some courses in 

 introductory microbiology consider this application of the aggluti- 

 nation reaction, a brief discussion will be presented for those who 

 want to use this material. 



About 45% of the blood in humans is comprised of cells— 

 leucocytes (white cells), erythrocytes (red cells), and platelets 

 (small discs or cell-like bodies of uncertain function). The re- 

 maining liquid portion of the blood is plasma, about nine-tenths of 

 which is water. 



An average human adult has about twelve or thirteen pints of 

 blood in his body containing a total of about thirty trillion 

 (30,000,000,000,000) red blood cells. Women have approximately 

 10% less blood than men, and persons living at high altitudes have 

 a materially higher erythrocyte count than those individuals re- 

 siding at or near sea level. 



During the last decade of the nineteenth century when funda- 

 408 



