Transfusing high Hgb because "patient still in shock"?

[Mabel Adams]

We have a 71 yo male patient who has had a week of horrid nosebleeds requiring emergency transfusion of 2 units and later crossmatched units, They eventually fixed the nosebleeds via Interventional Radiology after nothing else worked.  INR never above 1.4; Plt count always >100. Then he was found to have "coincidental diverticulitis complicated by perforation, ileus, and shock". They did a colectomy 18 hours ago, during which he was transfused 4 units RBCs. The op note includes, "A large volume of purulent fluid was evacuated from the abdomen.". That's 12 RBC units over 8 days, never more than 3 per day except during this surgery.  No plasma and never a massive transfusion. Seven hours ago, ~5 hours after the last transfusion, his Hgb was 13.1. They have not run another CBC. The surgeon wants to transfuse 2 more RBCs because he is "still in shock" and the pathologist approved it. Nothing in the chart says he is currently bleeding, just "Acute blood loss anemia still not equilibrated". What do we blood bankers not understand that would justify this transfusion? Is he at risk of overload? @Neil Blumberg  PS, our pathologists are generalists not transfusion medicine experts. 

[Neil Blumberg]

Hemoglobin and hematocrit re-equilibrate over minutes to an hour.  Usually minutes.  Not five hours. That's not compatible with what we know.  Transfusing a patient in this setting is more likely to cause inflammation, thrombosis, congestive heart failure, etc., than help, although it is understandable that the surgeon is trying to "do something" for a patient who is not responding to treatment.  The hemoglobin may or may not be precise, but it tells you that the circulating red cell mass isn't likely the problem.  If the patient is in shock and not bleeding, the problem is almost certainly not fixable by transfusion of red cells is my thought.  But desperation leads people to try stuff that is unlikely to help and may, in some cases, harm.  Likely cause(s) of the shock in such patients is cardiac dysfunction, sepsis or something else not easily fixable.  Not due to anemia/lack of red cell mass obviously.

[Mabel Adams]

Hgb now 14.6 and I see this in chart (by different surgeon), "Puzzling picture following adequate resuscitation; pH is normal, lactate has cleared, UOP and hemodynamic parameters have normalized; and yet base excess remains -10 and serum bicarb remains mid-teens. Anion gap is normal due to hyperchloremia."  I wonder if the surgeon yesterday was treating his base excess. I've heard her say (in the context of MTPs) that she doesn't really look at H&H but uses the base excess to determine if they need blood. We all know that H&H is a moving target during MTP.  Not sure treating base excess works when patient not bleeding, but I am not the expert.  Today's problem list (new surgeon) includes "septic shock", but I see no positive cultures and the list also includes some mostly resolved issues such as "acute blood loss anemia".  Still, there was that "large volume of purulent fluid" pulled from his abdomen.  At least we have filled him up with O neg blood now so maybe he will have less of the first 5 units of O pos that he got for the nosebleed circulating (2 units emergency issued and 3 more units over the next day or so) and not make anti-D.

[Neil Blumberg]

Just for the record, I am not aware of any data, nor can I conceive of a mechanism by which red cell transfusion would correct base excess.  This patient apparently had an extensive and severe infection, so vasodilation due to septic shock seems a real possibility.  Transfusing a patient to a hemoglobin of 14.6 is not something I've ever heard experts in anesthesiology and intensive care medicine advocate, and transfusion to this level would be expected to increase the risk of thrombosis greatly.   

And just for completeness, the diagnosis of septic shock in a patient with a recent serious infection and also likely receiving broad spectrum antibiotics does not require the presence of positive cultures for diagnosis.  Hard to grow bugs in vitro when there are high concentrations of anti-microbials.  This is why DNA tests are probably a better tool to diagnose infection in such patients, if available.  Does not require growth, just the presence of bacterial nucleic acids.

Edited September 13 by Neil Blumberg