Patient selection: Trauma patient following immediate resuscitation.
Goal: To minimize the amount of blood transfused.
Parameters:
(1) underlying status of the patient
(2) hemoglobin value used as the decision level to transfuse
(3) evidence of hypovolemia
(4) evidence of impaired oxygen delivery
The hemoglobin value used to trigger transfusion varies with the underlying status of the patient:
(1) The default level set by the authors was a hemoglobin < 7 g/dL.
(2) A healthy patient with no comorbid conditions can tolerate a lower hemoglobin level.
(3) A patient with severe cardiovascular disease will often require transfusion at a higher hemoglobin level to prevent cardiac ischemia. For the implementation I will use 10 g/dL ("liberal threshold" for acute blood loss)..
Criteria for impaired oxygen delivery - one or more of the following:
(1) low oxygen saturation in mixed venous blood
(2) persistent base deficit
(3) lactic acidosis
Management steps, performed on an ongoing basis:
(1) If the hemoglobin is less than the transfusion decision level, then transfuse the patient.
(2) If the patient is hypovolemic, then administer fluids to achieve normovolemia. Following fluid administration recheck hemoglobin.
(3) If there is evidence of impaired oxygen delivery, then consider:
(3a) placement of a pulmonary artery catheter
(3b) measurement of the cardiac output
(3c) optimize oxygen delivery
