A primary goal in the intrapartum period is to minimize the chance that the pregnant woman has recently received her thromboprophylaxis or higher dose anticoagulants when she desires labor epidural analgesia or needs a neuraxial anesthetic. Key elements in proactive planning include well-established protocols for elective procedures and tools to guide the decision-making process in unplanned circumstances. To facilitate anesthetic decisions in urgent or emergent situations, the SOAP VTE taskforce members have created Decision Aids (Figures 3 and 4) that integrate the ASRA guidelines, pharmacokinetics of anticoagulants in pregnancy, and the competing risks of general anesthesia and fetal well-being.
The integrity and continued growth of the multidisciplinary care team depends, in part, on a culture that promotes nonjudgmental debriefings of cases.
In conclusion, the use of anticoagulant thromboprophylaxis will likely increase in pregnant and postpartum women in the United States in response to recent guidelines and recommended practice changes. The SOAP consensus statement lays the foundation for proactive planning, and multidisciplinary team communication to ensure that pregnant women who qualify for thromboprophylaxis or higher dose anticoagulants will continue to safely benefit from neuraxial anesthesia without an increased risk of SEH.
The taskforce committed to attaining full consensus, in light of the limited available evidence and the potential confusion created by disparate published guidelines on this topic. This approach was particularly controversial for women receiving UFH 5000 U SQ twice daily. Many of the taskforce experts endorsed proceeding with neuraxial anesthesia without a time delay citing the favorable, albeit limited, pharmacokinetic data and the historical lack of reported SEH in this setting. However, some experts felt that there were insufficient data to assess the population risk of SEH with expanded use of thromboprophylaxis, and therefore, it was appropriate to err on the side of being more conservative. In response, the updated ASRA and the SOAP consensus recommendations incorporated language acknowledging that in some instances, the risks of SEH in a pregnant woman receiving neuraxial anesthesia may be lower than the risks of general anesthesia and it may be appropriate to proceed with a neuraxial procedure without delay. All parties agreed that more studies are needed to effectively assess the effects of UFH and LMWH on coagulation in pregnant women and the incidence of SEH in this context.
In urgent clinical settings where pregnant women have received recent thromboprophylaxis or higher dose anticoagulants, the Decision Aids and detailed commentary can help clinicians, in discussion with their patients, make better informed decisions about the competing risks of neuraxial compared to general anesthesia. Further research and rigorous reporting of complications and missed opportunities for neuraxial anesthesia are needed to inform future guidelines in this area.
The full list of members of the SOAP VTE Taskforce is as follows: Chairs of the SOAP VTE Taskforce are as follows: Lisa Leffert, MD, Co-Chair (Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts) and Ruth Landau, MD, Co-Chair (Department of Anesthesiology, Columbia University College of Physicians and Surgeons, New York, New York). Members of the SOAP VTE taskforce are as follows: Katherine Arendt, MD, (Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota); Shannon M. Bates, MDCM, MSc (Department of Medicine, Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada); Alexander Butwick, MBBS, FRCA, MS (Department of Anesthesia, Stanford University School of Medicine, Stanford, California); Brendan Carvalho, MBBCh, FRCA, MDCH (Department of Anesthesia, Stanford University School of Medicine, Stanford, California); Heloise Dubois, BS (Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts); Roshan Fernando, MBChB, FRCA (Department of Anaesthesia and Perioperative Medicine, University College London Hospital, London, United Kingdom); Alex Friedman, MD (Department of Obstetrics and Gynecology, Columbia University College of Physicians and Surgeons, New York, New York); Terese Horlocker, MD (Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota); Tim Houle, PhD (Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts); Sandra Kopp, MD (Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota); Douglas Montgomery, MD (Kaiser Permanente Riverside Medical Center, Riverside, California); Joseph Pellegrini, PhD, CRNA, FAAN (Department of Organizational Systems and Adult Health, Nurse Anesthesia Program, University of Maryland School of Nursing, Baltimore, Maryland); Richard Smiley, MD, PhD (Department of Anesthesiology, Columbia University College of Physicians and Surgeons, New York, New York; he reports stocks owned by spouse from Abbott Labs, Amgen, and Abbvie, outside of the submitted work); and Paloma Toledo, MD, MPH (Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois).
We would like to thank Charles-Marc Samama, MD, PhD, FCCP (Paris Descartes University) for reviewing the section on the “Assessment of Coagulation Status and Spinal Epidural Hematoma Risk in Pregnancy.”
a The Anesthesia Closed Claims Database is funded by the Anesthesia Quality Institute (AQI), the quality division of the ASA. Results were obtained via personal communication from Karen Posner, PhD, Laura Cheney, Professor in Anesthesia Patient Safety, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA. Website: www.asaclosedclaims.org.
b Pregnant patients receiving LMWH heparin without additional risk factors have <1% risk of HIT, and therefore routine monitoring of platelet counts is not recommended.
c The AQI, established in 2008, created the National Anesthesia Clinical Outcomes Registry in 2010 to assess adverse events and improve quality of anesthetic care. The National Anesthesia Clinical Outcomes Registry reports on 45 metrics, such as admission, perioperative mortality, and pain measures.
d MedWatch, founded by the US FDA, is an online, voluntary, adverse event–reporting system available to health professionals and patients.
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