Management of I HAVE NOTHING TO Category II FHRT- A DISCLOSE Standardized Approach Steven L. Clark, M.D. Texas Children’s Hospital/Baylor College of Medicine Rates of neonatal encephalopathy and cerebral palsy remain unchanged
WHY? • Maybe we have simply expected too much of a single physiologic parameter – heart rate. “A disappointing story” Roger Freeman, MD New Eng J Med 1990 WHY? WHY? • Maybe the use and interpretation of FHRM is • Maybe we have simply expected too much of so vastly disparate and inconsistent that this a single physiologic parameter – heart rate. variation overwhelms and masks the intrinsic • Can we really expect analysis of heart rate value of a highly effective tool. alone to give us a detailed window into CNS oxygenation and acid/base balance of a baby one minute before birth when we know it is of virtually no value in monitoring these parameters one minute after birth?
WHY? • Maybe the use and interpretation of FHRM is so vastly disparate and inconsistent that this variation overwhelms and masks the intrinsic value of a highly effective tool. • Because of this inconsistency, there has never been a standard, testable hypothesis dealing with interpretation and management of FHRT. Inconsistent application of a tool may mask its intrinsic value
Fetal Heart Rate Monitoring A Device Introduced Without an Instruction Manual Category I
Category III >80% of all FHRT exhibit category II patterns No specific, authoritative guidelines for management of these patterns exist. Category II FHRT • Present in vast majority of patients. • These are the cases that are missed and cause preventable fetal injury. • These are the cases that result in litigation. • These are the cases that result in unnecessary cesareans. • Yet no clear management guidelines exist!
Management of Category II FHRT General Principles • Goal is to delivery babies before they develop severe acidemia – implications for variability and decelerations.
General Principles Mean 5 th Percentile Nulliparas Rate of cervical dilatation 3 cm/hr 1.2 cm/hr Duration of 2 nd stage 33 min 117 min Multiparas Rate of cervical dilatation 5.7 cm/hr 1.5 cm/hr Duration of 2 nd stage 8.5 min 46.5 min • Goal is to delivery babies before they develop E. Friedman: Progression of spontaneous labor at term: 1978 What Constitutes “Normal Progress”? severe acidemia – implications for variability and decelerations. Suggested definition of “Normal Progress” • Progress in labor must also be considered. Nulliparas Active phase: 1 cm/hr Second stage: 2 hours Multiparas Active phase: 1.5 cm/hr Second stage: 1 hour General Principles General Principles • Goal is to delivery babies before they develop • Sudden, catastrophic events can never be severe acidemia – implications for variability eliminated • Features such as fetal tachycardia are not and decelerations. • Progress in labor must also be considered. addressed: other patterns will emerge prior • Moderate variability/accelerations remain the to need for delivery. only reliable sign that no damaging hypoxia/acidemia is present
Definitions The algorithm treats absent and minimal Variability variability as being equivalent despite the literature supporting the fact that only the • Variability = predominant pattern over 30 min. former reliably reflects a high degree of • Marked variability = moderate variability correlation with severe fetal acidemia. • Diminished variability = Absent variability MINIMAL Application of Algorithm Definitions • May be delayed for up to 30 minutes to try S ignificant Decelerations intrauterine resuscitation. • Variables: ≥60 bpm from baseline X ≥ 60 sec • Applied every 30 minutes while category II • Variables: < 60 bpm X ≥ 60 seconds regardless pattern persists. • When delivery is indicated, deliver within 30 of baseline • Any late decelerations minutes. • Discontinue if pattern changes to category I or III. • Does not apply to extreme prematurity, VBAC or abruption.
A PROLONGED DECELERATION WITH TACHYSYSTOLE Algorithm does not address prolonged decelerations Clinical Context is All Important Examples
IUGR FETUS WITH Additional Points OLIGOHYDRAMNIOS • This is not intended to represent THE exclusive standard of care.
Additional Points • This is not intended to represent THE exclusive standard of care. • This is intended to represent ONE approach which complies with the standard of care, as we see it. Additional Points Additional Points • This algorithm is not intended to represent • This algorithm will allow prevention of THE exclusive standard of care. preventable intrapartum HIE. • This algorithm is intended to represent ONE • Future modifications may allow the same approach which complies with the standard of results with less intervention (or maybe not.) • Use of this algorithm should provide both care, as we see it. • This algorithm is derived from currently optimal care, and optimal safety. available basic science, clinical evidence and expert opinion.
The Future? Random, ever-changing, individual interpretation and Options for management of labor management of abnormal FHRT is no longer an option Use the algorithm that Offer primary cesarean Offer unmonitored Offer labor only with represents current as the only way the only Such management only increases the labor as the way to best continuous category I evidence-based way to exclude avoid cesarean FHRT medicine intrapartum injury cesarean rate and adds to litigation woes without significantly improving outcomes.
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