title: Continuous monitoring of arterial blood gases and pH during intraoperative rapid blood administration using a Paratrend sensor.
abstract: OBJECTIVE
  The aim of this study was to determine the effects of rapid transfusion of packed red cells on the arterial blood gases and acid-base status of the recipient.
  
  
  METHODS
  We studied 16 patients (mean age 66.3+/-9.9 years) who received rapid transfusion of 632.8+/-287.2 g of packed red cells in CPDA-1, stored before use for a period of 15.2+/-4.4 days. During transfusion, monitoring of pH, PCO2 and PO2 was continuous using an intra-arterial multiparameter sensor (Paratrend 7, Biomedical Sensors, UK).
  
  
  RESULTS
  The rate of the transfusion was 73.1+/-9.6 g/min and the duration of observation was 35.8+/-12.8 min. Arterial pH decreased from 7.446+/-0.023 to 7.385+/-0.034 (p<0.001) and PCO2 increased from 32.31+/-1.35 to 36.41+/-1.86 mmHg (p<0.001). Delta pH and delta PCO2 showed significant correlation to the weight and the age of the transfused blood (p<0.001 for both dependent variables). The rate of pH change was positively but insignificantly correlated to the rate of the transfusion. Base excess was significantly decreased and end-tidal CO2 (PetCO2) was increased from 25.8+/-2.0 to 28.1+/-2.3 mmHg (p<0.05), significantly correlating to the amount and age of the administered component (p<0.05). PetCO2 was not elevated when PCO2 changes were minimal. Alterations in PO2 were not specific and our clinical impression was that they were related to unmeasured parameters.
  
  
  CONCLUSIONS
  Our findings suggest that the fall in pH and the elevation in PCO2 which occur during rapid transfusion of packed red cells may go undetected or be misinterpreted if the acid-base status of the recipient is not monitored continuously. These alterations are mainly of metabolic character and depend on the amount and age of the transfused component. Our data suggest that arterial sampling is essential during massive transfusions.
authors.affiliation: Department of Anaesthesiology, G. Gennimatas Hospital, Thessaloniki, Greece.
authors.forename: G
authors.initials: G
authors.lastname: Vretzakis
authors.forename: B
authors.initials: B
authors.lastname: Papaziogas
authors.forename: E
authors.initials: E
authors.lastname: Matsaridou
authors.forename: G
authors.initials: G
authors.lastname: Vasiliadou
authors.forename: G
authors.initials: G
authors.lastname: Papadopoulos
authors.forename: C
authors.initials: C
authors.lastname: Patsialas
authors.forename: F
authors.initials: F
authors.lastname: Kostopoulou
mesh_terms: D000368:Aged; D001158:Arteries / Q000502:physiology; D015374:Biosensing Techniques / Q000592:standards; D001784:Blood Gas Analysis; D001785:Blood Gas Monitoring, Transcutaneous; D017707:Erythrocyte Transfusion / Q000295:instrumentation* / Q000379:methods; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016018:Least-Squares Analysis; D008297:Male; D008875:Middle Aged; D010108:Oxyhemoglobins / Q000378:metabolism; D013514:Surgical Procedures, Operative
chemical_list: D010108:Oxyhemoglobins