PeriGen Research

ABSTRACTS

Title: Comparison of 5 experts and computer analysis in rule-based fetal heart rate interpretation
Publication: American Journal of Obstetrics and Gynecology
Date: July 14, 2010
Author: Parer JT, Hamilton EF

Full Article

Abstract:

OBJECTIVE: The purpose of this study was to measure agreement among 5 expert clinicians and a computerized method with the use of a strict fetal heart rate classification method.
STUDY DESIGN: Five providers independently scored 769 8-minute segments from the last 3 hours of 30 tracings with the use of a 5-tier color-coded framework that contains pattern descriptions and proposals for management. Computer analysis was performed with PeriCALM Patterns (PeriGen, Princeton, NJ) to detect and classify patterns.
RESULTS: The clinicians agreed exactly with the majority opinion in 57% (95% confidence interval [CI], 49-64%) of the segments and were within 1 color code in 89% (95% CI, 81-96%). The average proportion of agreement was 0.83 (95% CI, 0.73-0.94). Weighted Kappa scores averaged 0.58 (range, 0.48-0.68). The computer-based results were not statistically different: 0.87 and 0.52, respectively.
CONCLUSION: These 5 clinicians achieved moderate-to-substantial levels of agreement overall using a strictly defined method to classify fetal heart rate tracings. The result of the computerized method was similar to the conclusions of these clinicians.

Title: Graded classification of fetal heart rate tracings: association with neonatal metabolic acidosis and neurologic morbidity
Publication: American Journal of Obstetrics and Gynecology
Date: March 1, 2010
Author: Colm Elliot, MEng; Philip Warrick, PhD; Ernest Graham, MD; Emily F. Hamilton, MD

Full Article

Abstract:
OBJECTIVE: The objective of the study was to measure the performance of a 5-tier, color-coded graded classification of electronic fetal monitoring (EFM). STUDY DESIGN: We used specialized software to analyze and categorize 7416 hours of EFM from term pregnancies. We measured how often and for how long each of the color-coded levels appeared in 3 groups of babies: (A) 60 babies with neonatal encephalopathy (NE) and umbilical artery base deficit (BD) levels were greater than 12 mmol/L; (I) 280 babies without NE but with BD greater than 12 mmol/L; and (N) 2132 babies with normal gases. RESULTS: The frequency and duration of EFM abnormalities considered more severe in the classification method were highest in group A and lowest in group N. Detecting an equivalent percentage of cases with adverse outcomes required only minutes spent with marked EFM abnormalities compared with much longer periods with lesser abnormalities. CONCLUSION: Both degree and duration of tracing abnormality are related to outcome. We present empirical data quantifying that relationship in a systematic fashion. Copyright 2010 Mosby, Inc. All rights reserved.

Title: Effect of clinical-decision support on documentation compliance in an electronic medical record
Publication: Obstetrics & Gynecology
Date: August 1, 2009
Author: Shoshana Haberman, MD, PhD; Joseph Feldman, DrPH; Zaher O. Merhi, MD; Glenn Markenson, MD; Wayne Cohen, MD; Howard Minkoff, MD

Full Article

Abstract:
OBJECTIVE: To investigate the efficacy of enhancing an existing prompt system in our obstetric electronic medical record in regard to documentation of estimated fetal weights and indications for labor induction. METHODS: Preintervention rates of documentation of indications for labor induction and estimated fetal weight were established at two hospital sites that used the same obstetric electronic medical record system. A compliance adherence mechanism with an enhanced prompting system was installed at the intervention hospital. Changes in the percentage of records with completed documentation were then calculated at the intervention and control hospitals. Additionally, the effects of the intervention on the pattern of documentation of indications for labor induction and on the accuracy of estimated fetal weight were tested. RESULTS: In the intervention hospital, the documentation rate increased from 42% to 69.4% for indications for labor induction, and from 55.7% to 77% for estimated fetal weight (both P<.001) during the study period although the estimated fetal weight documentation rate did not reach the level seen at base in the control hospital (92.5%). In the control hospital, there were no significant changes in rates of estimated fetal weight during the study period, but there was a decrease in indications for labor induction documentation rates. The accuracy of estimated fetal weights did not change with the enhanced documentation compliance mechanism. CONCLUSION: Increasing the frequency and modifying the methodology of prompts in an electronic medical record increased the documentation of both estimated fetal weight and indications for labor induction but did not lead to full compliance with documentation. LEVEL OF EVIDENCE: I.

Title: Is Shoulder Dystocia with Brachial Plexus Injury Preventable?
Publication: Fetal and Maternal Medicine Review
Date: December 1, 2008
Author:  Henry Lerner, MD and Emily Hamilton, MD et al.

Full Article

Abstract: The sequelae of shoulder dystocia with persistent brachial plexus injury (BPI) are among the most serious of obstetrical complications. Shoulder dystocia with BPI generally places second or third in the list of the top causes of permanent birth-related neonatal injuries. Apart from the devastating medical and social consequences of lifelong impairment for the family, ensuing litigation with its allegations regarding poor care exacts a heavy toll on the medical profession.

Title: Partnering with technology to reduce OB losses
Publication:  Journal of Healthcare Risk Management
Date: December 2007
Author: Larry L. Smith, JD and Dorothy Berry, RN, BSN, HRM, CPHRM

Full Article

Abstract: Following a catastrophic birth injury that occurred as a result of deviations from the expected standards of care, the OB Risk Reduction Task Force of a healthcare network identified criteria to transform care at the bedside from theory to practice: 1) protocol-driven, real-time alerts to help healthcare providers meet clinical guidelines; and 2) the ability to produce reliable data to monitor and measure adherence to accepted standards of care. The group selected a technological solution to achieve that end. This case study illustrates how a strong partnership model between healthcare and technology solution providers can achieve much when both parties are focused on the same goals of performance improvement and active risk reduction.

Title: Shoulder dystocia: What if you could see it coming?
Publication: CONTEMPORARY OB GYN
Date: November 2007
Author: Henry Lerner, MD, Emily Hamilton, MD

Full Article

Abstract: The authors say that this formula—which focuses on the size of both the baby and the mother—allows obstetricians to determine which women are at greatest risk for shoulder dystocia with permanent brachial plexus injury.

Title: Labor Pains Unraveling the Complexity of OB Decision Making
Publication: Critical Care Nursing Quarterly
Date: December 2006
Author: Hamilton A, Wright, E.

Full Article

Abstract: While a discussion of technology and childbirth seems paradoxical, the use of statistical modeling can extend the capacity of the human mind to quantify risk, to communicate clearly, and to recognize when action is necessary in an obstetrical setting. These models provide clinicians envelopes that define safe and reasonable clinical paths. They obviate the myriad of environmental, experiential, and individual factors that inevitably affect the process of identifying and responding to unsafe situations. As the number of variables increases, the ability of the human mind to analyze multiple, interrelated factors diminishes and is not consistent across place and time. The top obstetrical problems leading to birth-related injury and litigation are discussed: shoulder dystocia, hypoxic ischemic encephalopathy, and prolonged or difficult labor. Two case histories are presented to demonstrate the factors promoting medical error and the application of these new technologies.

Title: Prediction of risk for shoulder dystocia with neonatal injury
Publication: Journal of Obstetrics and Gynecology
Date: July 17 2006
Author: Dyachenko A, Ciampi A, Fahey J, Mighty H, Oppenheimer L, Hamilton EF

Full Article

Abstract:
OBJECTIVE: The purpose of this study was to develop a predictive model of risk for shoulder dystocia (ShD) with injury. STUDY DESIGN: Medical records in 3 urban university teaching hospitals were reviewed to identify and characterize 498 cases of ShD, including 90 with neonatal injury and a comparison group with of 622 with vaginal delivery (VgD) without ShD. The data were subjected to logistic regression modeling to find the best combination of variables to discriminate between the injury and VgD groups. RESULTS: The best model included birth weight in combination with maternal height and weight as well as gestational age and parity. A score over 0.5 detected 50.7% of the shoulder dystocia cases with brachial plexus injury along with a false positive rate of 2.7%. CONCLUSION: Using a statistical model it is possible to identify adverse combinations of factors that are associated with ShD and neonatal injury along with a relatively low false positive rate.

Title: Fetal heart rate deceleration detection from the discrete cosine transform spectrum.
Publication: Abstract presentation at EMBS
Date: Jan 1 2005
Author: Philip A. Warrick, Doina Precup, Emily Hamilton, Robert Edward Kearney

Full Article

Abstract: Automated detection of decelerations in fetal heart rate (FHR) signals can be posed as a problem of signal detection in the presence of noise. We present an algorithm that adaptively selects the resolution of analysis and uses the discrete cosine transform (DCT) to describe the spectrum at short-term and longer-term scales. In so doing we generate near-orthogonal and scale-invariant features that are presented to a feedforward neural network for classification.

Title: Neural network based detection of fetal heart rate patterns
Publication: Abstract presentation at IJCNN
Date: Jan 1 2005
Author:     Philip Warrick, Emily Hamilton, Maciej Macieszczak

Full Article and Abstract

Title: Fetal heart rate patterns and hypoxic ischemic encephalopathy
Publication: American Journal of Perinatology
Date:  Jan 1 2005
Author: EF Hamilton, RW Platt

Full Article and Abstract

Title: The effect of computer-assisted evaluation of labor on cesarean rates
Publication: Journal of Healthcare Quality
Date: Jan 1 2005
Author: Hamilton E, Platt R, Gauthier R, McNamara H, Miner L, Rothenberg S, Asselin G, Sabbah R, Benjamin A, Lake M, Vintzileos

Full Article

Abstract: Dystocia, or slow labor, is the leading cause of first-time cesarean sections. Current diagnostic guidelines for dystocia are vague, and there is no clear postoperative confirmatory evidence to assess the correctness of this diagnosis. For several decades, various professional organizations have indicated that cesarean rates could be lowered safely and have recommended levels that are far below national averages. The three major factors, of roughly equal importance, associated with cesarean for slow labor are the baby's weight, the mother's height, and the threshold at which the physician believes it is reasonable to intervene. The last is the only modifiable factor, and quality programs are a major part of changing medical behavior. By using two study designs, the effect of a mathematical method for evaluating labor progress on the rate of cesarean section was measured. In the prospective randomized clinical trial, the relative risk of cesarean in the experimental group was unchanged at 1.04. In the pretest-posttest analysis, the rates fell from 19.54% to 17.04% at 6 months and 16.62% at 12 months.