1 December 2015

Platelet Count Considerations for Labor Epidural Catheter Placement Guidelines

The Society for Obstetric Anesthesia and Perinatology (SOAP) Patient Safety Committee surveyed its members to assess current practices surrounding labor epidural catheters and platelet counts. The survey results highlighted the varying parameters for requiring a routine platelet count prior to labor epidural placement in low-risk patients.

The clinical significance of thrombocytopenia and the need to routinely obtain a platelet count on all parturients prior to a neuraxial block are areas of debate. Causes for thrombocytopenia range from gestational thrombocytopenia, idiopathic thrombocytopenia, preeclampsia and HELLP syndrome. According to Anesthesia and Analgesia, there is a 5-7 percent incidence of asymptomatic thrombocytopenia (platelet count less than 150K) in women presenting for delivery. The ASA guidelines strongly agree that obtaining a platelet count in patients with suspected or existing preeclampsia, HELLP syndrome or a suspected coagulopathy reduces maternal anesthetic complications. However, the ASA obstetrical guidelines state that “The anesthesiologist’s decision to order or require a platelet count should be individualized and based on a patient’s history, physical examination, and clinical signs. A routine platelet count is not necessary in the healthy parturient.” Unfortunately, no data define the platelet count that will insure against the occurrence of an epidural hematoma. Most clinicians feel comfortable with a platelet count between 80-100,000, although if platelet counts are stable and there are no confounding comorbidities, some practitioners will proceed with platelet counts as low as 50,000. When faced with a low platelet count or downward trend in platelet number, a thorough history and physical exam directed at any evidence of petechiae, ecchymosis or oozing from IV sites is needed.

The balance between efficiency and safety cannot always be easily reconciled when timely pain relief could outweigh clinical best practices: pain is considered “the 5th vital sign” and timely pain relief can contribute to overall patient satisfaction. Similarly, abnormal lab results often necessitate further testing that can be of low clinical yield and cause further procedural delay. Laboratory turnaround times for specimen processing can be a source of provider and patient dissatisfaction.

The decision to perform a neuraxial block depends on many factors: history and physical exam, laboratory findings, and clinical course. Considerations when developing guidelines for your unit include:

  1. Are there individuals who can reliably assess which patients require a platelet count?
  2. Are there individuals who can accurately evaluate patients throughout the labor processes? If a patient’s condition changes to show signs and symptoms of preeclampsia, it must be determined whether there is an appointed provider who can evaluate and order a platelet count.
  3. Are there anesthesia practitioners in your group who are not comfortable proceeding without a resulted platelet count if one is ordered, even if the parturient is healthy?

Determine what a “healthy parturient” is for your particular unit and develop guidelines. For patients who have no signs or symptoms of preeclampsia and lack comorbidities, ordering or waiting for a platelet count may not be warranted. In high risk patients who have attendant comorbidities, or who have a suspected coagulopathy, obtaining a platelet count may be advisable. It is important for all practitioners and staff, including labor and delivery nurses and obstetricians, to agree which patients fall into each category so that each patient receives the care indicated for their situation.

Discuss laboratory requirement rationale with obstetricians and nurse leadership. It is worth investing the time to discuss management decisions with staff. Often there are reasons to proceed with neuraxial analgesia in the presence of low platelet counts. For example, explaining the traumatic nature of an epidural needle and catheter compared to a single shot spinal technique can support particular clinical decisions. Similarly, the desire to avoid intubation can support a neuraxial approach when faced with a low platelet count.

Operationalize a reasonable and safe approach to routine lab studies. It is important to develop a reasonable, livable and safe protocol for your particular unit’s patient population and clinical environment. Anesthesia practitioner experience in regional anesthesia skill sets often varies within a group practice. There must be allowance for individual practice and consideration for evidence-based clinical choices. Members of an anesthesia department should discuss parameters for lab requests to avoid confusion and delay in patient analgesia. Varying practices exist due to institutional differences and group culture, so implementation and sustained change of lab requirements should include education of obstetricians, nurse midwives, and labor and delivery nurses regarding supportive evidence for platelet count requirements. Continued adherence to lab requirements necessitates departmental consensus and ongoing support of established criteria. Clear and well communicated policies can help support both safe and efficient neuraxial analgesia.