Clinical trial NCT00787241: Platelet Count Trends in Pre-eclamptic Parturients
Official title: Platelet Count Trends in Pre-eclamptic Parturients: What is the Predictive Value of an Initial Platelet Count During Labor?
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Obstetric Labor Complications
Preeclampsia
Thrombocytopenia
Keywords: Platelets
Labor
Preeclampsia
Lead sponsor: Northwestern University
Sponsor class: OTHER
First posted: 2008-11-07
Enrollment: 445
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Pregnant Women

Brief summary: Thrombocytopenia (platelet count \< 100,000/mL) occurs in approximately 15% of women with preeclampsia. Neuraxial analgesia is contraindicated in parturients with a coagulopathy; therefore, the platelet count(PC) is routinely checked prior to the initiation of neuraxial analgesia in women with preeclampsia/eclampsia. Catheter removal is also contraindicated in the presence of a coagulopathy. Some women have an acceptable PC at the initiation of neuraxial analgesia, but may become significantly more thrombocytopenic during labor and delivery. In a study of severely preeclamptic parturients, some with HELLP (H=hemolysis of red blood cells, EL=elevated liver enzymes, LP=low platelet count) syndrome, the admission PC correlated with the PC nadir. However, the natural progression of the PC has not been studied in women with mild preeclampsia. We hypothesize that women with mild preeclampsia or severe preeclampsia without HELLP syndrome, and whose admission PC is greater than 150,000/mL, will have a stable PC during the course of labor and delivery and do not require another PC check prior to initiation of neuraxial analgesia or removal of the epidural catheter. The purpose of this study is to determine the positive predictive value of an initial PC greater than 150,000/mL for maintaining a PC greater than 80,000/mL during labor and delivery.

Detailed description: All women who delivered from 1/2000 through 12/2002, with the discharge diagnosis of mild preeclampsia, severe preeclampsia (including HELLP and eclampsia), and preeclampsia superimposed on chronic hypertension were identified through the Perinatal Database. Platelet counts (PC) for each patient, from one month prior to the delivery admission, until hospital discharge, were analyzed. The number of PC determinations per parturient was determined. For each diagnosis, the positive predictive value (PPV) of an initial PC \> 150,000/mL for maintaining subsequent PC \> 80,000/mL, as well as the PPV of the PC prior to initiation of neuraxial analgesia was calculated. The median time interval from the closest PC determination to initiation of neuraxial analgesia was calculated.

Eligibility criteria: Inclusion Criteria:

* All participants who delivered between January 1, 2000 and December 31, 2002, identified as having preeclampsia (without HELLP syndrome) in the Perinatal Database.

Exclusion Criteria:

* Participants not diagnosed with preeclampsia and/or outside the given criteria dates.

Primary outcomes:
measure: Positive Predictive Value of Earliest Available Platelet Count
timeFrame: 0 to 72 hours following delivery
Secondary outcomes:
measure: Positive Predictive Value of Platelet Count Closet to Neuraxial Analgesia
timeFrame: 0 to 72 hours following delivery
measure: Time Interval (Hours) From Closet Platelet Count to Initiation of Neuraxial Analgesia
timeFrame: 1 week to time of neuraxial analgesia
Other outcomes:
Locations:
city: Chicago
country: United States
facility: Northestern University
state: Illinois
Study officials:
affiliation: Northwestern University
name: Cynthia A Wong, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Weiner CP. Preeclampsia-eclampsia syndrome and coagulation. Clin Perinatol. 1991 Dec;18(4):713-26.
citation: Leduc L, Wheeler JM, Kirshon B, Mitchell P, Cotton DB. Coagulation profile in severe preeclampsia. Obstet Gynecol. 1992 Jan;79(1):14-8.