Introduction: Arterial blood gas (ABG) equipment can also report a bematocrit (HCT) from the ABG specimen. Our hypotheses were two-fold; 1) the platelet component of the complete blood count (CBC) rarely leads to alterations in therapy, even when abnormal, and 2) the HCT obtained from the ABG specimen correlates well with the HCT obtained by CBC. If these hypotheses are correct, the routine CBC on admission in trauma patients could be eliminated. Methods: This was a prospective observational study, blinded to all clinicians. The records of all patients seen in the resuscitation area of our Level 1 Trauma Center between 10/20/95 and 11/27/95 were examined daily. Data regarding ABGs, CBCs, and evidence of interventions made on the basis of abnormal CBC values was recorded Statistical analysis was with Student's west Significance was set at p<.05. Results: 338 patients were seen in the trauma resuscitation area during the study period. 273 had CBCs; 235 were returned from the laboratory with platelet counts. 7 patients with platelet counts completed had abnormally low counts, only one of which was below 50,000/mm3 (36,000/mm3). No patients were transfused platelets in the resuscitation area. Hematocrit and hemoglobin were lower (32% vs. 40%, 10.9g/dl vs. 13.7g/dl, p<.001) in patients transfused in resuscitation. 220 patients had ABGs. Mean pH was lower (7.31 vs. 7.40, rX.OOl) and base deficit was wider (6.6 vs. 1.9, p<.001), in patients transfused in resuscitation. 136 patients had both ABG and CBC. The correlation coefficient (r) of hematocrit obtained by CBCvs. ABG was .93. Conclusion: Platelet count, part of the CBC, was rarely abnormal and led to no specific interventions. HCT obtained by ABG accurately reflects HCT measured by CBC. If initial hematocrit is used in making the decision to transfuse, it is best obtained from the ABG, to the exclusion of the performance of a CBC. The ABG provides more information (pH, base deficit) that is predictive of transfusion. ABG analysis with same specimen HCT should replace the routine CBC in trauma resuscitation.
ASJC Scopus subject areas
- Critical Care and Intensive Care Medicine