OB Early Warning Criteria

Monitoring, also known as clinical surveillance, is ongoing patient assessments, which will identify problems and trigger responses.¹ A warning system is a process that defines observation criteria and sets a limit to trigger a response.¹ Although non-obstetric warning systems have existed for nearly twenty years, there has not been a system to use for obstetric women until recently.

Maternal morbidity and mortality are still on the rise in the United States. Severe maternal morbidity has risen over 200% in the United States from 1993 to 2014.² There are some known reasons for this increase; increases in maternal age, pre-pregnancy obesity, preexisting chronic medical conditions, and cesarean delivery.³ Hemorrhage, hypertension, infection, and venous thrombosis with delays in recognition, diagnosis, and treatment are the cause of many preventable maternal deaths.¹

From 2003 to 2005, the Saving Mothers’ Lives report recommended a modified early obstetric warning system. This system assessed vital signs and scored the woman based on the results. An algorithm was then used to determine what the woman needed. The score showed whether the woman was fine, needed closer monitoring, or needed immediate attention.⁴

After several studies, it was determined that a single-parameter risk assessment system that favors simplicity and specificity over complexity and sensitivity would be easier with an increase in patient specificity. Maternal mortality reviews have shown that in women who died, a disproportionate number demonstrated frankly abnormal vital signs, suggesting that a single-parameter system should maximize specificity for patients who are developing a critical illness.¹ The maternal early warning criteria were created based on what these reviews have shown.

Note. BP = blood pressure.

These triggers cannot address every possible clinical scenario that could be faced by an obstetric clinician and must not replace clinical judgment. As a core safety principal, the bedside nurse should always feel comfortable with escalating concerns at any point.¹

All women who meet any of The Maternal Early Warning Criteria should receive prompt bedside evaluation by a physician with the ability to activate resources in order to initiate emergency diagnostic and therapeutic interventions as needed.¹ It is important to note that one abnormal measure could have been inaccurate; therefore, it should be repeated. If the patient's provider is unavailable for a prompt evaluation, a covering provider should evaluate the patient. If a woman meets criteria and the reason cannot be determined, a maternal-fetal medicine consult, a hospital intensivist consult, or a rapid response team action initiated. Some electronic medical records can be programmed to alert the RN and page appropriate resources (such as the attending physician) when the patient meets criteria.

The most significant barrier to implementing an early warning criteria system is physician and administration buy-in. Providers may not want to be bothered, especially when they are not available. It is crucial to have an in-house provider to cover these circumstances. However, many providers are reluctant to respond to and treat another provider's patients. Nurses who are making the call to the provider may have a difficult time calling a provider who will not respond appropriately. It is vital for hospital administration to support an early warning criteria policy and ensures that providers follow it. Nurses may improve the use of the criteria if they receive praise or acknowledgment for using the criteria appropriately.

The Council on Patient Safety in Women’s Healthcare, a subcommittee of the American College of Obstetrics and Gynecology (ACOG) and the Association of Women’s Health, Obstetric, and Neonatal Nursing (AWHONN) both support the use of maternal early warning criteria. The findings in maternal morbidity reviews support the use as well.⁵

Each hospital should have a policy that includes the criteria to trigger the early warning system, whom to notify, how to notify them, how rapidly to expect a response, and when and how to activate the clinical chain of command in order to ensure an appropriate response.⁵

Maternal early warning criteria can prevent maternal mortality. There are studies to support the effectiveness of these criteria. There are cases of complications such as preeclampsia that may not be preventable, but prompt treatment may prevent maternal morbidity or mortality. All nurses should know these criteria and have a process to activate a response.

Patient M.S. is a 42-year-old who delivered her first baby via c-section 3 hours ago. She had moderate to heavy bleeding during her recovery. Her estimated blood loss measured 1200mL. Her vital signs have been stable. She transfers to the mother-baby unit at 11 pm. She begins to complain of severe abdominal pain. She is given Dilaudid for the pain of 9 out of 10 on the pain scale. Her bleeding is moderate. Her BP is 128/84, HR 140, respirations 18, temp 98.6. Her pulse ox is 98% on room air, and her urine output is adequate. The RN assumes the elevated HR is due to her pain. The RN returns in 1 hour to check on this patient and finds her lethargic with a BP 90/60, HR 150, pulse ox 94%. The RN calls a rapid response. The patient ends up in the OR with a massive hemorrhage requiring a massive transfusion and transfers to ICU.

1. Were the RN's actions appropriate?
2. Should the early warning criteria have been activated?
3. Could the massive transfusion have been prevented?

At 11pm, the patient’s HR met early warning criteria. The HR should have been rechecked and the provider called. The RN’s actions were not appropriate. HR could be elevated due to pain, but the woman had already had a hemorrhage and her bleeding was still moderate. A massive transfusion may have been prevented if the patient was treated with blood products sooner, but it is impossible to say it was preventable. The woman should have received care sooner though.

1. Mhyre JM, Doria R, Hameed AB, et al. The Maternal Early Warning Criteria: A Proposal from the National Partnership for Maternal Safety. Journal of Obstetric, Gynecologic & Neonatal Nursing. 2014;43(6):771-779. DOI:10.1111/1552-6909.12504.
2. Severe Maternal Morbidity in the United States | Pregnancy. Accessed December 1, 2019. Visit Source.
3. Queenan JT. Protocols for High-Risk Pregnancies: An Evidence-Based Approach. Wiley-Blackwell; 2015.
4. Behling DJ, Renaud M. Development of an Obstetric Vital Sign Alert to Improve Outcomes in Acute Care Obstetrics. Nursing for Women's Health. 2015;19(2):128-141. DOI:10.1111/1751-486x.12185.
5. Maternal Early Warning Criteria. Council on Patient Safety in Women's Health Care. Published June 11, 2019. Accessed December 5, 2019. Visit Source.