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J A Thorp

Publications and source records attributed to J A Thorp.

At least 37 records · Page 2Linked to original sources
PubMed1996

Epidural analgesia in labor: an evaluation of risks and benefits.

BACKGROUND: Intrapartum epidural analgesia has become increasingly popular because it is the most effective method of providing pain relief during labor. Much attention is given to its safety and efficacy, and many health care providers and consumers are unaware of its potential drawbacks. This article reviews the literature about the effects of epidural analgesia on the mother and infant. METHODS: We performed a computer-assisted MEDLINE search for articles and a review of bibliographies from articles on epidural analgesia. When reported data were incomplete, authors were contacted for more detailed information. RESULTS: The most common procedure-related complications, hypotension, inadvertent dural puncture, and headache, are easily treated and usually self-limited. Permanent morbidity and mortality are rare. Retrospective studies and randomized controlled trials both demonstrate that epidural analgesia is associated with increases in duration of labor, instrument vaginal delivery, and cesarean birth. To date only three trials randomized patients to narcotic versus epidural groups, and all showed a twofold to threefold increase in cesarean section for dystocia. Limiting epidural use in nulliparous labor and delaying its placement until after 5 cm of cervical dilation may reduce the risk of operative intervention for dystocia. Epidural analgesia may also increase intervention for fetal distress. Several studies show its association with maternal fever in labor. Its association with chronic back pain, neonatal behavioral changes, and maternal-infant bonding are more tenuous and require further study. CONCLUSIONS: Epidural analgesia is a safe and effective method of relieving pain in labor, but is associated with longer labor, more operative intervention, and increases in cost. It must remain an option; however, caregivers and consumers should be aware of associated risks. Women should be counseled about these risks and other pain-relieving options before the duress of labor.

Analgesia, Epidural↗
PubMed1995

The predictive value of maternal serum testing for detection of fetal anemia in red blood cell alloimmunization.

OBJECTIVE: Current management protocols for pregnancies complicated by red blood cell alloimmunization use the maternal antibody titer to predict the need for invasive testing for detection of fetal anemia. We investigated the use of three maternal serum tests to assess their usefulness in predicting fetal disease: indirect Coombs' titer, Marsh score, and monocyte monolayer assay. STUDY DESIGN: Forty-seven serum samples from pregnant women with red blood cell antibodies associated with fetal anemia were analyzed at cordocentesis. Fetal blood was analyzed for hematocrit (corrected for gestational age) and antigen status. Fetal anemia was defined as a hematocrit value of < 2 SD from the mean value for gestational age. Fetuses were classified into three groups: Antigen positive with anemia (n = 19), antigen positive without anemia (n = 17), antigen negative (n = 11). Statistical methods included Kruskal-Wallis test, Newman-Keuls test, Spearman's rank correlation, and receiver-operator characteristic curves; p < 0.05 was considered significant. RESULTS: The median monocyte monolayer assay (phagocytosis, adherence, and association) did not differ among the three groups. Both maternal titers and Marsh scores were significantly higher in fetuses with anemia compared with the other two groups of fetuses (256 vs 64 vs 64, p < 0.001, and 86 vs 69 vs 64, p = 0.02, respectively). Both titer and Marsh score exhibited significant correlations with corrected fetal hematocrit (r = -0.70, p < 0.001; r = -0.63, p < 0.001, respectively). Comparison of the overall receiver-operator characteristic curves for titer and Marsh score revealed no statistical difference; however, a Marsh score of 57 was noted to have a superior specificity than a titer of 16 (p = 0.02). CONCLUSION: The maternal Marsh score can be performed in conjunction with standard indirect Coombs' titers to enhance the predictability of fetal anemia.

Coombs Test↗
PubMed1995

The effect of maternal oxygen administration during the second stage of labor on umbilical cord blood gas values: a randomized controlled prospective trial.

OBJECTIVE: Our aim was to determine whether supplemental oxygen during the second stage of normal labor affects cord blood gas and cooximetry values. STUDY DESIGN: Patients at term pregnancy were prospectively randomized to the control or treatment group at the onset of the second stage of labor. The treatment group received 10 L/min oxygen by face mask, which result in a mean fractional inspired oxygen concentration of 0.81. RESULTS: There were 86 patients randomized into the study. In the oxygen group there were significantly more cord arterial pH values < 7.20 (9/41 vs 2/44, p < 0.05). The control group was compared with two subgroups of patients receiving oxygen: those receiving oxygen therapy for < or = 10 minutes and those receiving oxygen for > 10 minutes. Analysis of variance demonstrated significant differences (7.285 +/- 0.058, 7.312 +/- 0.056, 7.237 +/- 0.064; F test 8.3, p = 0.0005). Among several independent variables, regression analysis demonstrated that only duration of oxygen therapy had a significant inverse relation to cord arterial pH (F test = 15.6, p = 0.0002). CONCLUSIONS: Prolonged oxygen treatment during the second stage of normal labor resulted in a deterioration of cord blood gas values at birth.

Adult↗
PubMed1995

Heparin versus normal saline as a peripheral line flush in maintenance of intermittent intravenous lines in obstetric patients.

OBJECTIVE: To compare heparin sodium (100 United States Pharmacopeia U/mL) with 0.9% sodium chloride for use in the maintenance of intermittent intravenous (IV) devices during pregnancy. METHODS: Women at 26-34 weeks' gestation who required serial phlebotomy were assigned randomly to heparin or normal saline flush, administered in a double-blind fashion. Catheter sites were examined and flushed with the study solution at least once every 6 hours. Partial thromboplastin times (PTTs) were measured at catheter insertion and 48 hours later. Statistical analysis was performed with Student t test, Mann-Whitney U test, Fisher exact test, log-rank, and X2 analysis, as appropriate. RESULTS: There was a significant increase in catheter patency rate at 48 and 72 hours in the heparin group (26 of 31 versus 17 of 33, and 21 of 31 versus nine of 33, respectively; P < .01). In addition, there was a significantly lower rate of catheter complications in the heparin group (four of 31 versus 13 of 33; P < .01). There were no differences in PTTs. CONCLUSION: During pregnancy, dilute heparin flush to maintain patency of intermittent IV site devices results in the following: a greater catheter patency rate at 48 and 72 hours after insertion of the catheter, a lower rate of catheter complications requiring therapy, and no alteration in PTT.

Adult↗
PubMed1995

Combined antenatal vitamin K and phenobarbital therapy for preventing intracranial hemorrhage in newborns less than 34 weeks' gestation.

UNLABELLED: ōk--q----_xD-xD whether maternal antenatal therapy with vitamin K and phenobarbital prevents intracranial hemorrhage in premature newborns. METHODS: Women at high risk for spontaneous or indicated premature delivery before 34 weeks' gestation were randomly assigned to receive either placebo or vitamin K and phenobarbital. All patients received betamethasone and antibiotics and were managed uniformly by a single perinatal group in one hospital. All newborns were managed uniformly in the same nursery by one neonatal group. Two independent interpretations of neonatal head ultrasound examinations were obtained. RESULTS: The duration of gestation at study entry and at delivery were similar in the placebo (181 mothers) and treatment (191) groups. With the hospital radiology group (the primary interpreter), the incidence rates of severe intracranial hemorrhage (8 versus 7%) and mild intracranial hemorrhage (38 versus 32%) were similar for both groups. With the secondary interpreter (a single pediatric radiologist), the incidence rates of severe intracranial hemorrhage (9 versus 7%) and mild intracranial hemorrhage (27 versus 26%) were also similar. Neonatal mortality was equivalent in both the placebo and treatment groups (8 versus 10%). CONCLUSION: Combined antenatal therapy with vitamin K and phenobarbital does not reduce the frequency or severity of intracranial hemorrhage in premature newborns.

Adolescent↗
PubMed1995

The effect of combined antenatal vitamin K and phenobarbital therapy on umbilical blood coagulation studies in infants less than 34 weeks' gestation.

OBJECTIVE: To determine if antenatal vitamin K and phenobarbital therapy affect coagulation studies in umbilical blood at birth, and to provide 95% reference ranges for umbilical blood coagulation parameters in premature gestations. METHODS: Patients at imminent risk for spontaneous or indicated premature delivery less than 34 weeks' gestation were randomized to receive either placebo or vitamin K and phenobarbital. Prothrombin time (PT), activated partial thromboplastin time (PTT), functional coagulation factors, and decarboxylated prothrombin assays were performed on umbilical blood specimens. Decarboxylated prothrombin, also known as "protein induced by vitamin K absence-factor II" or precursor prothrombin, is a sensitive marker for vitamin K deficiency. Standardized values of PT and PTT are reported in seconds and standardized values of factor assays in percentage of normal adult functional activity (mean +/- one standard deviation). RESULTS: Newborns in the placebo and treatment groups had similar umbilical blood PT (12.6 +/- 1.2 versus 12.7 +/- 1.4 seconds), PTT (48.8 +/- 13.4 versus 49.6 +/- 13.8 seconds), and functional activity of factor II (40.3 +/- 12.5 versus 42.0 +/- 12.1%), factor VII (67.0 +/- 20.9 versus 66.8 +/- 18.9%), factor IX (27.4 +/- 12.8 versus 25.8 +/- 8.9%), and factor X (47.0 +/- 12.8 versus 49.2 +/- 11.6%). Newborns in the treatment group were about half as likely as those in the placebo group to have detectable decarboxylated prothrombin levels in umbilical blood at birth (gestational age-adjusted odds ratio 0.47, 95% confidence interval 0.22-1.01; P = .05). CONCLUSIONS: Combined maternal therapy with vitamin K and phenobarbital before premature delivery does not affect umbilical blood PT, PTT, or functional activity of vitamin K-dependent coagulation factors II, VII, IX, and X. However, it is associated with the reduced presence of decarboxylated prothrombin in umbilical blood at birth. There is significant improvement in umbilical blood coagulation tests as gestational age advances from 24 to 34 weeks.

Adult↗
PubMed1995

Parvovirus B19 infection in hospital workers: community or hospital acquisition?

A suspected nosocomial outbreak of parvovirus B19 infection in a maternity ward was investigated in February 1994. Questionnaires were administered and sera collected from maternity ward staff (n = 91), other ward staff in the same hospital (n = 101), and maternity ward staff at a nearby hospital (n = 81). Blood donors (n = 265) were used as community controls. Recent infection (parvovirus B19 IgM positivity) in susceptible persons (parvovirus B19 IgG-negative or IgM-positive) was common among all 4 groups (23%-30%). This high rate of recent infection occurred during a large community outbreak of fifth disease. Environmental samples collected from a room where a stillborn parvovirus B19-infected fetus was delivered were positive for parvovirus B19 DNA. Thus, this suspected nosocomial outbreak actually reflected transmission outside the hospital, but contaminated environmental surfaces were identified as one potential source for transmission of parvovirus B19.

Antibodies, Viral↗
PubMed1995

Current concepts and controversies in the use of vitamin K.

Vitamin K is a fat-soluble vitamin crucial to the production of many proteins involved with the coagulation process. It is integral in the synthesis of coagulants (factors II, VII, IX and X) and anticoagulants (proteins C and S). It is generally recognised that routine administration of vitamin K (phytomenadione) shortly after birth will prevent major neonatal morbidity and mortality related to haemorrhage. Vitamin K supplementation during pregnancy is also recommended if mothers are on anticonvulsant therapy or prolonged treatment with certain antibiotics. These medications, if ingested by pregnant women, predispose the neonate to a bleeding tendency caused by vitamin K deficiency. Vitamin K treatment of pregnant mothers before premature delivery has also been suggested to reduce the incidence of severe intracranial haemorrhage (ICH) in premature neonates. Although further studies are pending, the data to date do not support using antenatal vitamin K for preventing ICH.

Anticonvulsants↗
PubMed1994

Epidural analgesia in labor and cesarean delivery for dystocia.

Published studies assessing the effect of epidural analgesia in nulliparous labor on the frequency of cesarean delivery for dystocia are reviewed. There are at least four retrospective studies and two prospective studies that suggest that epidural analgesia may increase the risk of cesarean delivery for dystocia in first labors. The potential for epidural to increase the frequency of cesarean delivery for dystocia is likely influenced by multiple variables including parity, cervical dilatation at epidural placement, technique of epidural placement, management of epidural during labor, and the obstetrical management of labor after placement of epidural analgesia. Two studies suggest that delaying placement of the epidural until 5 cm of cervical dilatation or greater may reduce the risk of cesarean birth. Epidural is safe and may be a superior labor analgesic when compared with narcotics. However, patients should be informed that epidural analgesia may increase the risk of cesarean birth in first labors.

Analgesia, Epidural↗
PubMed1994

Antepartum vitamin K and phenobarbital for preventing intraventricular hemorrhage in the premature newborn: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To determine whether antepartum phenobarbital and vitamin K reduce the risk of intraventricular hemorrhage in premature newborns. METHODS: Patients at imminent risk for spontaneous or indicated premature delivery between 24-34 weeks' gestation were randomized to receive either placebo or vitamin K and phenobarbital. All patients received betamethasone and antibiotics and were managed uniformly by a single perinatal group in one hospital. All newborns were managed uniformly in the same facility by a single neonatal group. RESULTS: There was a nonsignificant reduction in all grades of intraventricular hemorrhage in the treatment group when compared to the placebo group (48.2 versus 38.3%; P > .05). Frequencies were reduced for severe intraventricular hemorrhage (grades 3 and 4) (6.0 versus 2.5%; P > .05) and mild intraventricular hemorrhage (grades 1 and 2) (42.2 versus 35.8%; P > .05). CONCLUSIONS: Antepartum phenobarbital and vitamin K effected a nonsignificant reduction in both mild and severe intraventricular hemorrhage. The incidence of severe intraventricular hemorrhage in our control group was significantly less than that observed in previous studies.

Cerebral Hemorrhage↗
PubMed1993

The effect of intrapartum epidural analgesia on nulliparous labor: a randomized, controlled, prospective trial.

OBJECTIVE: Our purpose was to determine the effect of epidural analgesia on nulliparous labor and delivery. STUDY DESIGN: Normal term nulliparous women in early spontaneous labor were randomized to receive either narcotic or epidural analgesia. RESULTS: When compared with the group receiving narcotic analgesia (n = 45), the group receiving epidural analgesia (n = 48) had a significant prolongation in the first and second stages of labor, an increased requirement for oxytocin augmentation, and a significant slowing in the rate of cervical dilatation. Epidural analgesia was associated with a significant increase in malposition (4.4% vs 18.8%, p < 0.05). Cesarean delivery occurred more frequently in the epidural group (2.2% vs 25%, p < 0.05), primarily related to an increase in cesarean section for dystocia (2.2% vs 16.7%, p < 0.05). CONCLUSIONS: In a randomized, controlled, prospective trial epidural analgesia resulted in a significant prolongation in the first and second stages of labor and a significant increase in the frequency of cesarean delivery, primarily related to dystocia.

Adult↗
PubMed1993

The risk of pulmonary edema and colloid osmotic pressure changes during magnesium sulfate infusion.

OBJECTIVES: The purposes of this study were to evaluate the effect of magnesium sulfate therapy on colloid osmotic pressure and to determine whether changes in colloid osmotic pressure increased the risk of pulmonary edema. STUDY DESIGN: During a 1-year time period 294 patients received parenteral magnesium sulfate for the treatment of preterm labor or preeclampsia. Both changes in colloid osmotic pressure and magnesium sulfate values and their relationship to clinical outcome parameters were analyzed. RESULTS: Serum magnesium levels were similar for both patients with preeclampsia and patients with preterm labor. Pulmonary edema developed in only four patients, all of whom had preeclampsia and low colloid osmotic pressure values. CONCLUSIONS: This study demonstrated that parenteral magnesium sulfate therapy does not cause significant changes in colloid osmotic pressure values until nearly 48 hours of continuous therapy.

Adult↗
PubMed1992

Nonimmune hydrops caused by massive fetomaternal hemorrhage and treated by intravascular transfusion.

Fetal hydrops at 26 weeks' gestation was diagnosed following a massive fetomaternal hemorrhage. Fetal intravascular transfusion was performed, and the hydrops completely resolved within 72 hours. The fetus required one more transfusion at 27 weeks' gestation. A subsequent percutaneous umbilical blood sampling at 30 weeks' gestation demonstrated a normal fetal hematocrit. A vaginal delivery at term resulted in a normal newborn. Massive fetomaternal hemorrhage is a well-known cause of nonimmune hydrops and may occur spontaneously in an otherwise normal pregnancy. Confirmation by percutaneous umbilical blood sampling and treatment by intravascular transfusion is recommended when massive fetomaternal hemorrhage causes hydrops in preterm gestations.

Adult↗
PubMed1992

Antepartum fetomaternal hemorrhage. Report of a case with the use of cordocentesis in diagnosis and management.

Clinical recognition of antepartum fetomaternal hemorrhage (FMH) is most often achieved by the observation of characteristic fetal heart rate (FHR) patterns and positive Kleihauer-Betke acid elution staining. Both methods are noted to lack sensitivity and specificity. A case of suspected antepartum FMH occurred with intermittent sinusoidal FHR tracings. Fetal blood sampling by cordocentesis in situations with equivocal antenatal testing, such as in this case, allows not only confirmation of fetal anemia but assessment of fetal acid-base status. In pregnancies of less than 32 weeks' gestation complicated by severe antepartum FMH, intravascular transfusion may be offered via this technique. Cordocentesis is beneficial in the management of pregnancies with uncertain FHR patterns when antepartum FMH is suspected.

Adult↗
PubMed1991

Hyporegenerative anemia associated with intrauterine transfusion in rhesus hemolytic disease.

Serial erythropoietin and ferritin levels were monitored in a fetus and newborn requiring three intravascular transfusions (in utero) for severe Rh disease. The newborn had a hematocrit of 37% at birth; however a hyporegenerative transfusion-dependent anemia developed and lasted approximately 3 months. The prolonged hyporegenerative anemia may be caused in part by erythropoietin suppression as a result of the fetal intravascular transfusions. In addition, anti-D antibody may also contribute to this anemia by a direct toxic effect on erythroid precursors and by peripheral hemolysis of reticulocytes.

Adult↗