Point-of-care viscoelastic testing with rotational thromboelastography (ROTEM) is associated with significant reductions in transfusion requirements and better outcomes in patients with severe postpartum hemorrhage.
“Contrary to our success in other areas in medicine, maternal mortality in the U.S. continues to grow, slowly but steadily,” said Denis Snegovskikh, MD, assistant professor of anesthesiology and associate chief of obstetrical anesthesia at Yale University School of Medicine, in New Haven, Conn. “Among other potentially preventable causes of this sad phenomenon, the Joint Commission identified more frequent episodes of severe obstetric hemorrhage. Although the work of an anesthesiologist has limited effect on leading causes of maternal mortality, our impact on outcomes among bleeding parturients is quintessential.
“It has been our mission at Yale to do everything possible to prevent mothers dying from bleeding,” he continued. “After the FDA approved the FIBTEM [involving fibrinogen] assay of ROTEM in 2012, we developed a new strategy in the management of massively bleeding patients. Goal-directed transfusion [GDT] is based on utilization of bedside testing devices, which provide comprehensive assessment of hemostasis and measure levels of hemoglobin and electrolytes in a matter of minutes.”
He added, “While the utilization of bedside viscoelastic testing devices was reported to improve outcome among cardiac patients and patients undergoing liver transplant, its impact on outcome in obstetric patients is essentially unknown.”
To help fill this information gap, Dr. Snegovskikh and his colleagues reviewed the records of patients who delivered at Yale-New Haven Hospital between Jan. 1, 2011 and July 31, 2015. The patients all had severe postpartum hemorrhage, which was defined as an estimated blood loss of 1,500 mL or greater.
Dramatic Improvement Found
Several clinical outcomes were abstracted from the patients’ medical records, including estimated blood loss, blood product replacement, hysterectomy, ICU admission and hospital length of stay. Of the 86 patients who met the study’s inclusion criteria, 28 underwent GDT based on point-of-care testing; 58 underwent transfusion before point-of-care testing was available. The groups were demographically similar.
“Point-of-care viscoelastic testing allowed a dramatic improvement in outcomes among parturients with severe postpartum hemorrhage,” Dr. Snegovskikh reported at the 2015 annual meeting of the American Society of Anesthesiologists (abstract A3032). Point-of-care testing was associated with less transfusion of packed red blood cells (1 vs. 4 median units; P<0.0001) and fresh frozen plasma (0 vs. 3 median units; P<0.0001). Furthermore, the percentage of patients receiving platelets was 0% in the GDT group compared with 44.6% of non-GDT counterparts (P=0.0001). Cryoprecipitate transfusion was similar between groups.
The GDT patients also fared much better with respect to outcomes. Only one patient (3.6%) required ICU admission, significantly fewer than the 25 non-GDT patients (43.1%; P=0.0001). “This is a tremendous financial savings,” Dr. Snegovskikh said in an interview with Anesthesiology News. Similarly, the median length of postpartum hospitalization was a day shorter in the GDT group (4 vs. 5 days; P=0.0007). Finally, only 25% of ROTEM patients underwent a hysterectomy, compared with 53.5% of those in the non-GDT group (P=0.02). Other differences are summarized in the Table.
“So not only are we getting a tremendous savings in terms of cost—with shortening the length of stay, decreasing ICU admission rates and reducing blood product usage—in GDT patients, but we also improved their outcomes,” he said.
These data, he added, suggest that point-of-care viscoelastic testing as part of a goal-directed transfusion strategy may change the face of severe postpartum he morrhage management. “I think the explanation is that when we implement goal-directed transfusion therapy, we individualize our care,” Dr. Snegovskikh said. “That allows us to perform transfusion therapy wisely and eliminate a lot of unnecessary transfusions. In the end, I think goal-directed transfusion should be utilized in any hospital for any patient who develops massive hemorrhage.”
Heather Nixon, MD, understood well the trial’s importance and relevance, as well as its potential drawbacks. “This is something that many obstetric anesthesiologists are interested in using,” said Dr. Nixon, assistant professor of anesthesiology and chief of the Division of Obstetric Anesthesiology at the University of Illinois College of Medicine, in Chicago.
“One of the big problems is that we are really just starting to define what the waveforms should look like in pregnant women, because they’re different than in normal patients. Pregnant women are hypercoagulable, so it makes the interpretation of the data a little more difficult in the middle of a hemorrhage.”
Even though Dr. Nixon lauded technologies that can quickly assist with goal-directed transfusion practices in the obstetric operating room, she recognized that larger studies are needed to define triggers for transfusion practices in the obstetric patient. In the interim, clinical vigilance will go a long way toward optimizing patient outcomes. “I think we still need to strive for accurate estimated blood loss calculations and evaluate the clinical signs of our patients,” she said.
The study results help demonstrate the importance of certain blood products in postpartum hemorrhage management. “I am heartened to see the authors report a decrease in the transfusion of packed red blood cells, platelets and fresh frozen plasma in the ROTEM group,” Dr. Nixon added. “However, the cryoprecipitate transfusion was not different between groups, and we know that fibrinogen levels are very predictive of the severity and subsequent morbidity during a postpartum hemorrhage. So this finding supports the use of cryoprecipitate transfusion as a necessary component in obstetric massive hemorrhage.”