The Daily Dose • Sunday, April 29

New Innovations in the Management of Postpartum Hemorrhage

By Dr. Nawal Ragheb-Mueller, from the IARS 2018 Annual Meeting*

Postpartum Hemorrhage is an event anesthesiologists invariably manage but dread. Every one of us will encounter it at some point: it’s the most common maternal morbidity in the developed world, affecting 18% of births in developed countries. However, with the evolution of our understanding of massive hemorrhage, the refinement of treatment approaches, and the advancement of team models, improved outcomes survival – and good outcomes – are no longer a pipe dream, but an expectation.

What is postpartum hemorrhage?

Defined as a loss of blood of greater than 500cc in the postpartum period.

What is a massive hemorrhage protocol?

A protocol to standardize the response to large blood loss in a variety of situations, including trauma, vascular, GI, OB and other emergent scenarios.

Interestingly, the use of an MHP seems to have some fairly variable results within the obstetric world. While statistically the use of the MHP improves the “appearance” of some measured parameters used for comparison (namely patient pH, patient temperature and presence of coagulopathy), these comparisons didn’t amount to a statistically significant change in net clinical outcome.

In thinking about the MHP, there are seven important phases, each contributing to its overall quality and safety: Triggering, Team, Testing, Tranexamic Acid, Temperature, Transfusion and Termination.

  • Triggering: How will your institution’s MHP be activated? Are we too quick or too slow to “pull the trigger” on initiating these protocols? Key point: It’s crucial to avoid under-triggering the system. Better to activate and terminate later if found to be unnecessary.
  • Team: Who is part of the MHP team? Are they fluent in the steps and procedures that comprise your institutions protocol? Key point: RNs and MDs should have the protocol memorized to avoid taking time to stop and re-read procedures. Adequate “drilling” needs to be performed to make sure entire team–from leading attending right down to blood product porters–are familiar with what to do.
  • Testing: While activation of the protocol shouldn’t necessarily wait for the return of laboratory results, labs should be sent and used to provide some objective evidence for the rational direction of MHP use.
  • Tranexamic Acid: TXA improves coagulopathy in the massive blood loss setting and should be part of any MHP.
  • Temperature: Temperature of less than 34C associated with an increase in mortality associated with blood loss and coagulopathy; temperature decreases by just 1C increase the risk of transfusion by 22%, and that risk compounds for every continued degree of temperature loss. Patient temps should be measured every 15 minutes and should not fall below 36C.
  • Transfusion: The old 1:1:1 paradigm needs refinement. This is a fine place for the MHP to start, but it should be targeted as soon as the patient’s actual needs are known.
  • Termination: We need to know when to stop! Transfusing just because “its there” leads to exposing the patient to blood products unnecessarily, as well as wastes precious resources.

Ultimately, MHPs are fantastic tools but need to be deployed by teams that are well-trained, and at institutions committed to post-activation analysis to allow continuous quality improvement.

Elucidating Fibrinogen’s Role

Fibrinogen has been isolated as a crucial parameter of interest when thinking about prevention, treatment and control of PPH. However, recent years have yielded a plethora of data, and, not surprisingly, some of it seems to conflict. Some key features of fibrinogen’s part in PPH:

  • Fibrinogen levels are a great marker to track severe PPH (defined as blood loss resulting in Hgb decrease greater than or equal to 4g/L, requiring greater than or equal to 4U of PRBC replacement, requiring hemostatic intervention, or resulting in death). In fact, the PPV of a fibrinogen level less than or equal to 2g/L in predicting severe PPH.
  • Increasing fibrinogen levels pre-emptively does not protect against PPH. One study noted that patients who received pre-emptive fibrinogen required just as much intervention for PPH-related events as their placebo-treated cohorts.
  • Triggering infusion of fibrinogen concentrate using FibTEM does not improve outcomes in PPH. However, restricting the use of FFP based on viscoelastometry is feasible and does not result in significantly different clinical outcomes – suggesting this type of test, like many of our tools, has a role to play but can’t be the “be all, end all.”
  • A good place to start for the activation of fibrinogen replacement in treatment of PPH might be a fibrinogen of less than 2g/L

As with many emerging frontiers in our field the landscape is ever-evolving; when it comes to prevention and treatment of PPH, the use of MTPs and attention to fibrinogen as a transfusion guide represent two crucial areas of further research and refinement.

*Cover from the Panel, New Innovations in the Management of Postpartum Hemorrhage