Biomedical subjects

M D Berkus

Publications and source records attributed to M D Berkus.

10 recordsLinked to original sources

PubMed1992

The development and testing of new instruments for operative vaginal delivery.

OBJECTIVE: Little innovation has occurred in recent years in the instruments available for operative vaginal delivery. The purpose of this study is to develop a technique to test the utility of an investigational device, the obstetric bonnet, and measure the forces it places on the fetal head. STUDY DESIGN: We constructed a model of the fetal head capable of measuring both compression and vacuum created by an applied device. A total of 18 devices were tested to a maximum traction of 60 pounds. RESULTS: A significant linear relationship exists between the traction applied and the compression (R2 = 0.42, p = 0.0004) and vacuum (R2 = 0.85, p = 0.0001) created. Compression and vacuum recorded at maximum recommended traction were 1.1 lb/sq in and 31 cm Hg, respectively. CONCLUSION: These findings explain the mechanics of this interesting device, and demonstrate forces that compare favorably with those known to occur with forceps or vacuum extraction.

Female↗

PubMed1992

Glucose tolerance test periodicity as a descriptor of glucose tolerance abnormality.

The periodicity of the standard 100-g glucose tolerance test (GTT) was examined in a prospective study of 194 pregnant patients to determine how well gestational diabetes could be identified. A simplified formula, the GTT periodicity, was used to estimate the time for the GTT curve to return to the fasting level. One hundred one study subjects had all normal glucose values by the National Diabetes Data Group criteria (0-abnormal group), 47 had one value greater than normal (1-abnormal group), and 46 had more than one value abnormal or gestational diabetes. The 0-abnormal patients had a significantly shorter GTT periodicity than did 1-abnormal or gestational diabetic mothers (3.6 versus 4.8 versus 6.6 hours, respectively; P less than .04). Calculating the periodicity for the corresponding insulin excursions yielded significantly increasing values in a graduated fashion for each group (5.2 versus 6.9 versus 9.6 hours, respectively; P less than .05). Examination of the oscillation of the GTT curve about the fasting level allows a physiologic description of normal and abnormal glucose responses in pregnancy. Furthermore, our findings suggest that glucose and insulin periodicities are useful predictors of gestational diabetes in patients with positive screening.

Adult↗

PubMed1991

Combination antibiotics and indomethacin in idiopathic preterm labor: a randomized double-blind clinical trial.

Subclinical infection may play a role in the failure of magnesium sulfate tocolysis. Using a double-blind randomized study design, we administered a combination of ampicillin-sulbactam and indomethacin or corresponding placebos to patients in preterm labor who were receiving intravenous magnesium sulfate tocolysis. The mean gestational age at enrollment was 30.1 weeks, and mean cervical dilatation was 2.15 cm. No differences were noted between placebo (n = 43) and study patients (n = 43) in gestational age at delivery, term deliveries, days gained, or neonatal outcome. Preterm delivery (less than 36 weeks) occurred in 61% of the total population. The likelihood of a beta error was 0.07 to 0.23 on the basis of outcome analysis. In our population adjunctive ampicillin-sulbactam with indomethacin did not improve the success of magnesium sulfate tocolysis.

Ampicillin↗

PubMed1991

Shoulder dystocia: should the fetus weighing greater than or equal to 4000 grams be delivered by cesarean section?

A total of 75,979 women who were delivered vaginally in the period 1970 to 1985 were stratified into diabetic and nondiabetic groups. Overall, the incidence of macrosomia (greater than or equal to 4000 gm) was 7.6% (5674/74390) in the nondiabetic group and 20.6% (328/1589) in the diabetic group. Patients were further subdivided by weight categories at 250 gm intervals. Eight percent of shoulder dystocia occurred in the diabetic group when fetal weight was greater than or equal to 4250 gm. In contrast, 20% of shoulder dystocia in the nondiabetic group could have been prevented by elective cesarean section when the fetal weight was greater than or equal to 4500 gm. Furthermore, logistic regression analysis demonstrated that birth weight, diabetes, and labor abnormalities were the principal contributors to shoulder dystocia. Elective cesarean section is strongly recommended for diabetics with fetal weights greater than or equal to 4250 gm, and trial of vaginal delivery for nondiabetic fetuses with weights greater than or equal to 4000 gm is recommended. In all cases the clinician must be watchful for labor abnormalities in macrosomic fetuses.

Birth Weight↗

PubMed1990

Does fasting interval affect the glucose challenge test?

The relationship between fasting interval and glucose screening was assessed in a prospective study of 153 non-diabetic pregnant patients undergoing a standard 50g glucose challenge test. An interval of less than 3 hours after the last meal was found to be associated with a significantly greater insulin response as opposed to a fasting interval of more than 3 hours (121.3 pmol/l vs. 83.5 pmol/l, p less than .001) and a greater insulin/glucose index (0.92 vs. 0.66, p less than .001), with no difference in plasma glucose. Overall, obese patients had a higher glucose response than non-obese, but only higher insulin levels (107 pmol/l vs. 69 pmol/l, p less than .001) and insulin/glucose index (0.79 vs. 0.59, p less than .02) when the fasting interval was greater than 3 hours. Our data suggest that the fasting interval can influence insulin response during a glucose challenge test and the aberration in insulin secretion may effect screening results, especially in the high-risk gravida with glucose abnormality.

Adult↗

PubMed1990

Relationships between glucose levels and insulin secretion during a glucose challenge test.

The relationship between glucose and insulin levels was examined in a prospective study of 153 pregnant patients without diabetes who underwent a standard 50 gm glucose challenge test. One hundred eighteen women had normal screening results (glucose level less than 140 mg/dl) and 35 had abnormal screening values but a normal oral glucose tolerance test. Abnormal responders had greater insulin levels (149 vs 82 pmol/L, p less than 0.0001), and a higher insulin/glucose index (0.96 vs. 0.72, p less than 0.007). Patients with glucose levels less than 100 mg/dl had significantly lower insulin/glucose indices. Overall, obese patients had significantly greater glucose and insulin measurements than did nonobese women, but there was no difference within normal and abnormal groups. Glucose levels accounted for 52% of the insulin output and 29% of the insulin/glucose index variance. Neither age, parity, nor obesity contributed significantly to insulin levels in the multiple regression model. Therefore the accepted threshold for glucose screening reflects abnormal insulin output and this aberration may be indicative of the primary defect in gestational diabetes.

Adult↗

PubMed1990

Effect of tocolytic agents on fetal umbilical velocimetry.

In this prospective study, we sought to examine the changes in umbilical vascular resistance induced by tocolytic therapy. Umbilical artery velocimetry was performed in 46 patients with preterm labor before tocolysis and at 1 hour and 24 hours after tocolysis was initiated. Raw systolic/diastolic ratios were corrected for concomitant changes in fetal heart rate. Thirty patients received subcutaneous terbutaline and 16 were treated with intravenous magnesium. Systolic/diastolic ratios decreased in patients treated with terbutaline. This decline persisted after correction for increases in fetal heart rate. No significant changes in systolic/diastolic ratios were seen in patients treated with magnesium. We conclude that terbutaline may affect umbilical vascular resistance. Possible clinical implications of these findings are discussed.

Blood Pressure↗

PubMed1990

Lamicel for induction of labor.

Lamicel is a synthetic osmotic cervical dilator currently used as a method of cervical dilation in first- and second-trimester pregnancy termination. It works by extracting fluid from the cervical tissue and softening the cervix. This study evaluated its effectiveness in nonelective medical induction of labor in high-risk patients. Forty inpatients who, for medical and obstetric reasons, required delivery within the next 24-48 hours were studied. Patients were evaluated to make certain that a 12- to 24-hour delay was safe for mother and child. The evening prior to the day of induction, a pelvic examination determined the Bishop score, and bacterial cultures were obtained from the endocervix. As many Lamicels as possible (usually one to three) were then placed in the endocervix without rupturing the membranes. The next morning the devices were removed, a repeat Bishop score obtained, amniotomy performed, internal monitors placed and oxytocin infusion initiated. Data were collected for preinsertion and postinsertion Bishop scores, induction-delivery times, duration of ruptured membranes, and cesarean and vaginal birth rates. Maternal and neonatal infectious morbidity was determined. A comparison group of patients with premature rupture of the membranes was selected. From data studied at our institution, patients were matched for parity and duration of labor (not significantly different from the Lamicel group). The study revealed that Lamicel can be an effective means of ripening the cervix for induction of labor.

Bacterial Infections↗

PubMed1986

Cohort study of Silastic obstetric vacuum cup deliveries: II. Unsuccessful vacuum extraction.

In a cohort analysis of Silastic vacuum extractor deliveries, 65% were completed with the vacuum extractor alone, 24% with outlet forceps, 3% with midforceps, and 7% with cesarean section (vacuum extractor-cesarean). Control groups were formed by using the next sequential forceps delivery, spontaneous vaginal delivery, and every second cesarean section after a trial of labor. The infants were examined using a neurobehavioral scale, an encephalopathy assessment, cranial ultrasound, and indirect ophthalmoscopy. In the combined vacuum extractor and forceps delivery subgroup (vacuum extractor-forceps), all but 3% were converted from a high mid-forceps delivery to outlet forceps by the initial vacuum extractor procedure, thus eliminating many difficult midforceps deliveries. The study yielded no significant difference in maternal morbidity between vacuum extractor-forceps and forceps delivery, no difference in vaginal trauma for vacuum extractor-cesarean versus vacuum extractor delivery, and no greater hospital stay, infection rate, or need for transfusion for either vacuum extractor-forceps versus forceps delivery or vacuum extractor-cesarean versus cesarean delivery. Neonatal morbidity did not differ between successful and unsuccessful trial of vacuum extractor, except for an increased frequency of retinal hemorrhage. The frequency of scalp trauma, including cephalohematoma, did not differ between vacuum extractor-forceps and forceps delivery, or between vacuum extractor-cesarean and vacuum extractor delivery. For vacuum extractor-forceps versus forceps delivery and vacuum extractor-cesarean versus cesarean section, there were no significant differences in neurobehavioral or encephalopathy scores, or in the frequency of neonatal jaundice, facial palsy, anemia, fractures, or mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Cesarean Section↗

PubMed1985

Cohort study of silastic obstetric vacuum cup deliveries: I. Safety of the instrument.

A prospective study was undertaken to determine the safety of the Silastic vacuum extractor. Between November 1982 and July 1983, a cohort of 84 successful vacuum extractor deliveries was examined, using the next sequential forceps delivery and spontaneous vaginal delivery as controls. In addition to routine neonatal morbidity measures, Scanlon early neonatal neurobehavioral scale and a modified Sarnat encephalopathy staging examination were used to critically assess neurologic functioning; a cranial ultrasound scan was performed to look for intracerebral hemorrhage, and an indirect ophthalmologic examination was done to assess the incidence of retinal hemorrhage. The study yielded no significant increase in maternal vaginal trauma for vacuum extractor versus spontaneous vaginal delivery, but there was a significantly greater incidence for forceps delivery (60%) versus vacuum extractor (25%) and more associated blood loss for forceps delivery (P less than .01). There was no significant increase in neonatal morbidity for vacuum extractor compared with forceps delivery nor in serious morbidity compared with spontaneous vaginal delivery. Specifically, for vacuum extractor versus forceps delivery there was no difference in one- and five-minute Apgar scores, extent of resuscitation, cosmetic injury, jaundice, mean neonatal intensive care unit stay, or incidence of retinal hemorrhage. Notably, there was no mortality related to delivery method, but there were two unrelated deaths. There were no cases of intraventricular or subgaleal hemorrhage on clinical or ultrasound examination, but one stillborn infant, who succumbed to a generalized coagulation defect, had a subarachnoid hemorrhage. Finally, there was no significant difference in Sarnat encephalopathy staging or Scanlon neurobehavioral assessment between spontaneous vaginal, forceps, and vacuum extractor deliveries.(ABSTRACT TRUNCATED AT 250 WORDS)

Apgar Score↗