Cristina Figueroa Villalba, MD, authored a provocative editorial, When minutes matter: the laboratory’s role in rapid hemostasis assessment in the May/June issue of CLN, a publication of ADLM. Please review this 10-minute read and respond with your recommendations for a rapid-test profile for acute hemorrhage. For instance, would you include a PTT, the DOASENSE® urinary dipstick for DOAC identification, near-patient viscoelastometry, or other choices? Please comment below.
From PBI research colleague, 6-7-26 Dr. Ali-Sadeghi-Khomami: Hi George, I am surprised that aPTT is not part of their bleeding panel. Totally agree, DOACs or anticoagulants in general need to be ruled out if the bleeder is not conscious. A point-of-care device will be a very timely fit in the emergency settings. Click this link to follow a graphic April 2026 LinkedIn post by Dr. Rabiah Alnoshan entitled How To Stop a Bleeder.
Also sent 6-7-26 from colleague Dr. Paul Riley, Portfolio Development & Engagement Scientist, Diagnostica Stago. We had a webinar on this topic in April from Dr. Wayne Chandler that describes a modified fibrinogen procedure to reduce TAT by removing the reflex option for low fib and using a modified low-to-moderate level calibration curve selected only for when low fib is suspected.
In my experience, the recommended assays are PT, fib, CBC (esp. platelets), hematocrit, and maybe anti-Xa with UFH/LMWH if DOAC recent exposure is suspected and the patient is unconscious or unsure of meds and last dose taken. The VET can be performed, but I thought that wasn’t really used for general bleeding risk screening–more for perioperative or severe trauma assessment, along with potentially obstetric, liver use, etc., depending on the method available.
Thank you George for your message and request for comments. In my previous workplace, PT, APTT and fibrinogen besides CBC was ordered. I am surprised as well that APTT is not included. Additionally, anti-Xa and tests for Verify Now (Asn = aspirin test) were ordered to rule out an anticoagulant effect. We did not have a 510(k) cleared DOAC available at that time so a qualitative result (present or absent) was provided based on anti-Xa UFH results to rule it out. For VET, a pathology consult was necessary at times for a rapid assessment, since it was not found required at times.
Hi George and Fritsma Factor readership,
As instructed by George, I have read both the piece by Dr Villalba and the questions raised by George on this post, and offer the following: i) be guided by what is available at your institution; ii) we would add an aPTT to the initial panel; not sure why it was not mentioned in Dr Villalba’s piece. Possibly since the aPTT can sometimes point to red-herrings, such as lupus anticoagulant (LA) or contact factor deficiencies (including factor XII) that do not cause hemorrhage. Thus, the aPTT is not useful as a predictor of bleeding, but can still be useful to investigate a bleeding patient, while being knowledgeable of its limitations. If everything (PT, aPTT, CBC, fibrinogen) is normal, then a factor deficiency as a cause of bleeding is low, but does not exclude FXIII deficiency nor a platelet function defect. If one or more of these initial screening assays are abnormal, then follow the abnormality. If the platelet count is low, maybe you have found the cause of bleeding. If one or more coag tests are prolonged, our first step is to perform mixing studies and thrombin times (TT). If you can use an LA-insensitive aPTT reagent as the coag screen, that’s great; if it is prolonged in the presence of a normal PT – perform FVIII, FIX, FXI, FXII. If the PT is only prolonged, could be FVII or an anticoagulant effect. If both prolonged, could be a common pathway or combined factors deficiency. Follow the trail. If mixing studies are normal (corrected), more likely a factor deficiency; if mixing studies still show a prolongation, could be a factor inhibitor (e.g., FVIII inhibitor if only aPTT was prolonged; FV inhibitor if both PT and aPTT were prolonged) or an anticoagulant (e.g., a DOAC) effect – in our lab we have anti-Xa and direct thrombin inhibitor assays available 24/7 for all the DOACs. In other labs, prolonged TT may suggest heparin or dabigatran (mix TT will be abnormal). Anti-Xa can be used to assess possibility of heparin, apixaban, rivaroxaban, edoxaban). In an emergency setting, DOASENSE® urinary dipstick for DOAC identification can be used instead if available.