Obstet Gynecol Clin North Am
June 2011
Despite persisting controversy over shoulder dystocia prediction, prevention, and injury causation, the authors find considerable evidence in recent research in the field to recommend additional guidelines beyond the current American College of Obstetricians and Gynecologists and Royal College of Obstetricians and Gynecologists guidelines to improve clinical practice in managing patients at risk for experiencing shoulder dystocia. In this article, the authors offer health care providers information, practical direction, and advice on how to limit shoulder dystocia risk and, more importantly, to reduce adverse outcome risk.
View Article and Find Full Text PDFBackground: Severe shoulder dystocia is disproportionately associated with large-for-gestational-age infants.
Case: A nulliparous patient at 38 weeks' gestation had an uncomplicated antenatal course. Clinical pelvimetry revealed an acute-angle pubic arch but otherwise normal diameters, conjugate and sacral concavity.
Objective: To determine if gestational age (GA) at delivery or tumor size impacts outcome in neonates with very large sacrococcygeal teratomas (SCTs).
Methods: Retrospective chart review from 1990 to 2006 of live-born infants with very large SCTs, defined as diameters exceeding 10 cm. Data analyzed using the independent t test and Fisher's exact test, with p values <0.
Fetal responses to induced maternal relaxation during the 32nd week of pregnancy were recorded in 100 maternal-fetal pairs using a digitized data collection system. The 18-min guided imagery relaxation manipulation generated significant changes in maternal heart rate, skin conductance, respiration period, and respiratory sinus arrhythmia. Significant alterations in fetal neurobehavior were observed, including decreased fetal heart rate (FHR), increased FHR variability, suppression of fetal motor activity (FM), and increased FM-FHR coupling.
View Article and Find Full Text PDFUsing an evidence-based, medical approach, the strengths and pitfalls of the causation- and standard-of-care-based arguments proffered by plaintiff and defense counsel in shoulder dystocia- associated birth injury litigation are reviewed based on medical plausibility. The role of the expert witness as arbiter of the relationship between medical care rendered and the untoward outcome of such care is distinguished from that of other court members. Proposed solutions to the medical malpractice litigation crisis are also examined in light of relevant differences in the pathogenetic bases for birth injuries of various types.
View Article and Find Full Text PDFA practical clinical review of those aspects of shoulder dystocia management that are directly relevant to birth injury is presented. In contrast to more popular viewpoints, the tenets of this paper are that, with few exceptions, clinically relevant, permanent brachial plexus injury is nearly universally associated with shoulder dystocia, injury is causally related to mechanical stresses induced during shoulder dystocia delivery, and management algorithms can be optimized to reduce the incidence of mechanical birth injury from shoulder dystocia. Advantages of direct rotational manipulation of the fetus within the birth canal are emphasized, supported by critical analysis of maneuver-related outcomes research.
View Article and Find Full Text PDFExtreme obesity remains a frustrating and formidable disease, with most sufferers requiring surgical intervention in order to achieve long-term, sustained weight loss. Most bariatric procedures today are performed on women, many of whom are of reproductive age; yet minimal evidence exists to guide clinicians in the care of such women before, during, and after pregnancy. This review outlines the fundamental nutritional and surgical alterations of the most commonly performed bariatric procedures with the aim to elucidate a physiologically sound approach to counseling and management of extremely obese women of childbearing age who are either contemplating or have already undergone bariatric surgery.
View Article and Find Full Text PDFObjective: Previous computer simulations of shoulder dystocia (SD) explored the effect of SD itself on the mechanical response of the fetus. Our objective was to perform a mechanical simulation study to explore the variations in fetal response during routine, unilateral SD (USD), and bilateral SD (BSD) deliveries.
Study Design: Using a biofidelic birthing simulator, we performed 30 experiments mimicking passage of the fetus through the pelvis.
Among risk factors for shoulder dystocia, a prior history of delivery complicated by shoulder dystocia is the single greatest risk factor for shoulder dystocia occurrence, with odds ratios 7 to 10 times that of the general population. Recurrence rates have been reported to be as high as 16%. Whereas prevention of shoulder dystocia in the general population is neither feasible nor cost-effective, intervention efforts directed at the particular subgroup of women with a prior history of shoulder dystocia can concentrate on potentially modifiable risk factors and individualized management strategies that can minimize recurrence and the associated significant morbidities and mortality.
View Article and Find Full Text PDFBackground: We sought to determine to what extent intraoperative salvaged red blood cells (RBC) might theoretically reduce exposure to appropriately transfused allogenic erythrocytes in Cesarean delivery patients.
Methods: Medical records of Cesarean delivery patients requiring blood transfusions from January 1, 1992 to June 30, 1996 and June 1, 1998 to June 30, 2003 were reviewed. For each patient, we calculated the number of allogenic RBC units that could have theoretically been avoided had intraoperative autotransfusion been performed, based upon estimated blood loss, preoperative hematocrit, and the amount of retrieved blood needed to yield a single RBC unit.
Conf Proc IEEE Eng Med Biol Soc
June 2007
We report on the design, testing and implementation of a novel birthing simulator developed specifically to research the delivery process and improve clinical training in uncommon but inevitable complicated human births. The simulator consists of a maternal model and an instrumented fetal model, used in conjunction with an existing force-sensing system and a data-acquisition system. The maternal model includes a bony, rotatable pelvis, flexible legs, and a uterine expulsive system.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
June 2007
We have created a bioimpedance probe designed to detect subtle changes in human cervical tissue composition in vivo, and thereby detect the onset of cervical remodeling in a noninvasive manner sooner than existing clinical methods allow. Our cervical bioimpedance measurement device, which can be used during a routine pelvic examination, is composed of a contoured probe with disposable tip and, within the probe's handle, a bioimpedance sensor equipped with an integrated chip capable of generating sinusoidal voltage of varying frequencies. A constant force spring assures consistent measurements through a range of contact forces applied.
View Article and Find Full Text PDFPurpose: To evaluate the efficacy of topical human amniotic fluid (HAF) in the treatment of ocular acute alkali burns in mice.
Design: Experimental study.
Methods: A chemical burn with 2 microl of sodium hydroxide 0.
Am J Obstet Gynecol
February 2006
Objective: To ascertain whether brachial plexus palsy (BPP) that occurs without shoulder dystocia (SD) represents a traction injury during unrecognized SD or a natural phenomenon with a different mechanism of injury, we compared risk factors and outcomes between SD-associated and non-SD-associated BPP.
Study Design: Neonates with BPP after cephalic vaginal delivery were pooled from all deliveries at Johns Hopkins (June, 1993-December, 2004) and a dataset of litigated permanent BPP from multiple institutions (1986-2003), grouped by SD association based on clinician documentation and compared by using Fisher exact and t tests.
Results: Thirty percent of 49 non-SD-BPP and 11% of 280 SD-BPP lacked all risk factors for SD (P = .
Background: Although many retrospective studies report that brachial plexus palsies occur after vaginal delivery in the absence of recorded shoulder dystocia, there are no known prospective reports by a treating clinician (PubMed, English language only, 1952-June 2004, search terms: shoulder dystocia, nonshoulder dystocia, obstetric brachial plexus injury, Erb's palsy, Erb-Duchenne palsy, spontaneous vaginal delivery).
Case: A multiparous patient presented with a birth plan requesting that the baby be allowed to deliver on its own, without traction on the head and without suctioning. Although induced at term for elevated blood pressure, the otherwise healthy patient experienced a normal labor with a 30-minute second stage.
This study investigated the trajectory of physiological and psychological functioning during the second half of pregnancy and compared responsiveness to a laboratory stressor between pregnant and non-pregnant women. Monitoring of 137 pregnant women at 20, 24, 28, 32, 36, and 38 weeks of pregnancy included measures of heart period (HP), heart period variability (HPV), skin conductance (SCL), respiratory period (RP), respiratory sinus arrhythmia (RSA), and self-report of mood disturbance. HP and RSA declined during this period; SCL and mood disturbance increased.
View Article and Find Full Text PDFObjective: This study was undertaken to objectively compare delivery traction force, fetal neck rotation, and brachial plexus elongation after 3 different initial shoulder dystocia maneuvers: McRoberts', anterior Rubin's, and posterior Rubin's.
Study Design: We developed a laboratory birthing simulator comprised of a maternal model with a 3-dimensional bony pelvis, an instrumented fetal model, a force-sensing glove, and a computer-based data acquisition system. A single operator performed 30 simulated shoulder dystocia deliveries using standard downward traction after 1 maneuver was performed.
Objective: In severe shoulder dystocia, when initial maneuvers fail, either episiotomy or fetal manipulation (Rubin, Woods' screw, or posterior arm release) is recommended. We sought to compare maternal and neonatal outcomes between severe shoulder dystocia deliveries managed with episiotomy versus fetal manipulation.
Study Design: We identified severe shoulder dystocia deliveries from three databases: all shoulder dystocia deliveries (1993-2003 and 1994-1997) from two teaching institutions and litigated cases of shoulder dystocia-associated permanent brachial plexus palsy from multiple U.
The enigmatic quality of the maternal-fetal relationship has been extolled throughout history with little empirical support. We apply time series analysis to data for 137 maternal-fetal pairs collected at 20, 24, 28, 32, 36, and 38 weeks gestation. Maternal heart rate and skin conductance data were digitized in tandem with fetal heart rate and motor activity.
View Article and Find Full Text PDFLongitudinal neurobehavioral development was examined in 237 fetuses of low-risk pregnancies from 2 distinct populations--Baltimore, Maryland, and Lima. Peru--at 20, 24, 28, 32, 36, and 38 weeks gestation. Data were based on digitized Doppler-based fetal heart rate (FHR) and fetal movement (FM).
View Article and Find Full Text PDFObjective: The purpose of this study was to compare the descent curves and second-stage length among grand multiparous, nulliparous, and lower parity multiparous women.
Study Design: Retrospective cohorts of spontaneously laboring, vertex-presenting, term, grand multiparous women (parity >or=5) from two medical centers over 5.5 years were matched randomly to nulliparous women and lower parity multiparous women controlled for age, hospital, and year of delivery.