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PubMed1987

Improved delivery through biological membranes. XXX. Synthesis and biological aspects of a 1,4-dihydropyridine based chemical delivery system for brain-sustained delivery of hydroxy CCNU.

A redox chemical delivery system based on the NADH in equilibrium NAD+ model was applied to an active metabolite (D) of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), i.e. CCNU-OH. The 1,4-dihydrotrigonelline ester of CCNU-OH, N-(2-chloro ethyl)-N'-[trans-4-(1,4-dihydro-1-methyl-3-pyridinecarbonyloxy)cyc lohexyl]- N-nitrosourea (D-CDS) was prepared by a direct hydride transfer reaction of the corresponding pyridinium precursor (D-Q+) with a highly reactive 1-benzyl-1,2-dihydroisonicotinamide. The in vitro kinetics in biological fluids indicated facile oxidative conversion of D-CDS to D-Q+. An in vivo study showed that one intravenous injection to rats of D-CDS resulted in rapid brain accumulation of D-Q+, followed by a sustained release of CCNU-OH, while D-Q+ was rapidly eliminated from systemic circulation. The ratio of brain/blood concentration of D-Q+ was found to increase progressively with time. At an equimolar dose of CCNU-OH, the ratio of brain/blood concentration for CCNU-OH was found to be close to unity.

Animals↗
PubMed2002

A state-wide assessment of the obstetric, anesthesia, and operative team personnel who are available to manage the labors and deliveries and to treat the complications of women who attempt vaginal birth after cesarean delivery.

OBJECTIVE: The purpose of this study was to determine on a state-wide basis the range of obstetric, anesthesia, and surgical team personnel who were available immediately to manage the labors and deliveries of women who attempted vaginal birth after cesarean delivery. Additionally, we tried to determine whether hospitals had stopped performing vaginal births after cesarean delivery or made changes in their policies regarding vaginal birth after cesarean delivery as a result of recent American College of Obstetricians and Gynecologists recommendations. STUDY DESIGN: Available immediately was defined as "being present in the hospital." All hospitals that provided obstetric care in the State of Ohio were surveyed to determine whether an obstetrician with cesarean privileges, an anesthesiologist, or an anesthetist capable of independently administering anesthesia for a cesarean section, and a surgical team were available immediately when women attempted vaginal birth after cesarean delivery. The hospitals were also asked whether they had stopped allowing vaginal births after cesarean delivery or had made changes in their vaginal birth after cesarean delivery policies in response to the recent recommendations of the American College of Obstetricians and Gynecologists. Data were computerized and analyzed by the chi(2) test. RESULTS: Seventy-seven (93.9%), 35 (100%), and 13 (100%) of level I, II, and III hospitals performed vaginal births after cesarean delivery. An obstetrician was immediately available in 27.3%, 62.9%, and 100% of level I, II, and III institutions, respectively (P <or=.001). Anesthesia availability was 39%, 100%, and 100% of level I, II, and III institutions, respectively (P <or=.001). A surgical team was available in 35.1%, 97.1%, and 100% of level I, II, and III hospitals, respectively (P <or=.001). A complete complement was available in 15.6%, 62.9%, and 100% of level I, II and III institutions, respectively (P <or=.001). Two hospitals had stopped the performance of vaginal births after cesarean delivery, and 10 additional hospitals were considering stopping the performance of vaginal births after cesarean delivery. Policy changes had been adopted in 15 institutions, and 4 other institutions were considering changes. CONCLUSION: Most level I and many level II hospitals provide less than optimum staffing when women are attempting vaginal birth after cesarean delivery. Because vaginal births after cesarean delivery are equally distributed among level I, II, and III institutions in this state, many women may be attempting vaginal birth after cesarean delivery under less than optimal conditions. The data suggest the need for changes in staffing or referral patterns to safely meet the Healthy People 2010 goal of increasing the vaginal birth after cesarean delivery rate nationally.

Anesthesia, Obstetrical↗
PubMed1999

Pharmacokinetics and consistency of pericardial delivery directed to coronary arteries: direct comparison with endoluminal delivery.

BACKGROUND AND HYPOTHESIS: Pharmacologic modulation of the contents of the pericardial space has been shown to influence the response of coronary arteries to balloon injury. Endoluminal (EL) local delivery of various drugs into coronaries has been found to be limited by short residence time, as well as by highly variable deposited agent concentration. We hypothesized that compounds placed into the pericardial space (P) would penetrate into coronary tissue with greater consistency than seen after EL delivery and provide for prolonged coronary exposure to agents. METHODS AND RESULTS: 125I-labeled basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF), albumin, or 131I-labeled diazeniumdiolated albumin (NONO-albumin) were delivered as model/therapeutic proteins into the porcine pericardial space (n = 15 pigs) or into coronaries using an EL delivery catheter (n = 48 arteries). In subjects receiving 125I-labeled proteins, the delivery target or mid-regions of the left anterior descending (LAD) and left circumflex (LCx) arteries were harvested at 1 h or 24 h for gamma-counting and autoradiography, and fractional intramural delivery (FID) or retention measured as percent agent in 100 mg artery/agent in infusate for both time points. In the animals receiving 131I-labeled NONO-albumin, serial gamma imaging was employed to evaluate the rate of redistribution in individual animals following either pericardial or endoluminal delivery. At 1 h, FID values ranged from 0.00064 to 0.0052% for P delivery (median 0.0022%), and from 0.00021 to 6.7 for EL delivery (median 0.27%). At 24 h, FID values ranged from 0.00011 to 0.003 for P delivery (median 0.0013), and from 0.0002 to 1.4 for EL delivery. The estimated T1/2 for bFGF redistribution from the vascular tissue was 22 h (P) and 7 h (EL), respectively, while the directly determined T1/2 values for NONO-albumin redistribution from the delivery region were 22.2 h (P) and 2.5 h (EL). CONCLUSIONS: These data show that pericardial fluid contents can access coronary arteries with intramural concentrations which typically vary by 10-15-fold, while EL delivery results in a remarkably wide intramural concentration range with up to 33,000-fold variability. The apparent redistribution rate is more rapid following EL delivery, possibly due to sustained diffusive tissue loading from the pericardial space. Pericardial delivery appears to offer substantial advantages over EL administration with respect to residence time and reproducibility.

Albumins↗
PubMed2006

IMRT delivery to a moving target by dynamic MLC tracking: delivery for targets moving in two dimensions in the beam's eye view.

A new modification of the dynamic multileaf collimator (dMLC) delivery technique for intensity-modulated therapy (IMRT) is outlined. This technique enables the tracking of a target moving through rigid-body translations in a 2D trajectory in the beam's eye view. The accuracy of the delivery versus that of deliveries with no tracking and of 1D tracking techniques is quantified with clinically derived intensity-modulated beams (IMBs). Leaf trajectories calculated in the target-reference frame were iteratively synchronized assuming regular target motion. This allowed the leaves defined in the lab-reference frame to simultaneously follow the target motion and to deliver the required IMB without violation of the leaf maximum-velocity constraint. The leaves are synchronized until the gradient of the leaf position at every instant is less than a calculated maximum. The delivered fluence in the target-reference frame was calculated with a simple primary-fluence model. The new 2D tracking technique was compared with the delivered fluence produced by no-tracking deliveries and by 1D tracking deliveries for 33 clinical IMBs. For the clinical IMBs normalized to a maximum fluence of 200 MUs, the rms difference between the desired and the delivered IMB was 15.6 +/- 3.3 MU for the case of a no-tracking delivery, 7.9 +/- 1.6 MU for the case where only the primary component of motion was corrected and 5.1 +/- 1.1 MU for the 2D tracking delivery. The residual error is due to interpolation and sampling effects. The 2D tracking delivery technique requires an increase in the delivery time evaluated as between 0 and 50% of the unsynchronized delivery time for each beam with a mean increase of 13% for the IMBs tested. The 2D tracking dMLC delivery technique allows an optimized IMB to be delivered to moving targets with increased accuracy and with acceptable increases in delivery time. When combined with real-time knowledge of the target motion at delivery time, this technique facilitates improved target conformality relative to no-tracking deliveries and allows PTV margin reduction.

Algorithms↗
PubMed2005

Preterm delivery predicted by soluble CD163 and CRP in women with symptoms of preterm delivery.

OBJECTIVE: To evaluate whether soluble CD163 (sCD163) and C-reactive protein (CRP) can predict spontaneous preterm delivery in women with symptoms of preterm delivery. DESIGN: Prospective cohort study. Setting Labour ward at a tertiary university hospital. POPULATION: Ninety-three women with symptoms of preterm delivery before 34 weeks of gestation. METHODS: sCD163 and CRP were individually examined as predictors of preterm delivery. A model for prediction of preterm delivery was established using exact logistic regression for risk factors individually associated with preterm delivery. MAIN OUTCOME MEASURES: Gestational age at delivery. RESULTS: In women with symptoms of preterm delivery, median sCD163 and CRP levels were significantly higher statistically in women delivering preterm (3.4 mg/L, and 62 nmol/L) compared with the women delivering at term (2.7 mg/L, and <48 nmol/L, Mann-Whitney U test, P < 0.01 and P < 0.001) for sCD163 and CRP, respectively. sCD163 above 5 mg/L was associated with an increased risk of preterm delivery (crude OR = 10, [95% CI 1.3-466], adjusted OR = 27, [0.7-infinity]). CRP above 47 mg/L was associated with an increased risk of preterm delivery (crude OR = 5 [1.8-14], adjusted OR = 5 [1.04-31]). Likelihood ratio of a positive test was 8.6 [2.8-14] and 2.8 [0-6.2] for sCD163 and CRP, respectively. The logistic regression model was able to predict 85% of preterm deliveries with 13% false positive, giving a likelihood ratio of 8 [2.2-13.5]. CONCLUSION: High levels of sCD163 or CRP are associated with an increased risk of preterm delivery in women with symptoms of delivery. Good prediction of preterm delivery before 34 weeks of gestation was obtained by a combination of preterm prelabour rupture of membranes (PPROM), overweight, relaxin, CRP and sCD163.

Antigens, CD↗
PubMed2003

Cohort study of maternal views on future mode of delivery after operative delivery in the second stage of labor.

OBJECTIVE: The purpose of this study was to assess maternal views on the future mode of delivery after either previous instrument vaginal delivery or cesarean delivery at full dilatation. STUDY DESIGN: We conducted a prospective cohort study of 393 women with term singleton cephalic pregnancies. RESULTS: More than one half of the cohort intended to have a further pregnancy, with no significant differences between the instrument vaginal delivery and caesarean delivery groups (51% vs 54% before discharge; adjusted odds ratio, 1.04; 95% CI, 0.2, 6.0), and there was little change in maternal views over time. Women were more likely to aim for a future vaginal delivery after an instrument vaginal delivery (79% vs 39% before discharge; adjusted odds ratio, 4.5; 95% CI, 2.2, 9.2), but the proportion decreased over time (68% vs 42% at 1 year; adjusted odds ratio, 3.6; 95% CI, 1.6, 8.1). There were no significant differences in preferred future mode of delivery for women who had a caesarean delivery after a failed instrument delivery and those who were delivered by immediate caesarean delivery. CONCLUSION: A high proportion of women who have had a previous difficult instrument vaginal delivery would still prefer vaginal delivery in a future pregnancy.

Cesarean Section↗
PubMed1990

[Primaparas' perceptions of their delivery experience and their maternal-infant interactions: compared according to delivery method].

One of the important tasks for new parents, especially mothers, is to establish warm, mutually affirming interpersonal relationships with the new baby in the family, with the purpose of promoting the healthy development of the child and the wellbeing of the whole family. Nurses assess the quality of the behavioral characteristics of the maternal-infant interaction. This study examined the relationships between primiparas perceptions of their delivery experience and their maternal infant interaction. It compared to delivery experience of mothers having a normal vaginal delivery with those having a cesarean section. The purpose was to explore the relationships between the mother's perceptions of her delivery experience with her maternal infant interaction. The aim was to contribute to the development of theoretical understanding on which to base care toward promoting the quality of maternal-infant interaction. Data were collected directly by the investigator and a trained associate from Dec. 1, 1987 to March 8, 1988. Subjects were a random sample of 62 mothers, 32 who had a normal vaginal delivery and 30 who had a non-elective cesarean section (but without other perinatal complications) at three general hospitals in Seoul. Instruments used were the Stainton Parent-infant Interaction Scale (1981) and the Marut and Mercer Perception of Birth Scale (1979). The first observations were made in the delivery room (for vaginally delivered mothers only), followed by day 1, day 2, day 3, and 2 weeks, 4 weeks, 6 weeks and 8 weeks after birth, for a total of 7-8 contacts (Cesarean section mothers were observed on days 4 and 5 but the data not used for analysis). Observations in the hospital were made during the hour prior to scheduled feedings. The infant was placed beside the mother. Later contacts were made at home. Data analysis was done by computer using as SPSS program and included X2 test, paired t-test, t-test, and Pearson Correlation coefficient: the results were as follows. 1. Mothers who had a normal vaginal delivery tended to perceive the delivery experience more positively than cesarean section mothers (p = 0.002). The finding supported the hypothesis I that perception of delivery would vary according to the method of delivery. Mother's perceptions of birth were classified into three dimensions, labor, delivery and the baby. There was a significantly different and positive perception by the vaginally delivered mothers to the delivery experience (p = 0.000) but no differences for labor or the baby according to the delivery method (p = 0.096, p = 0.389).(ABSTRACT TRUNCATED AT 400 WORDS)

Cesarean Section↗
PubMed1981

[Differential peridural analgesia for vaginal delivery. A randomised study of its influence on the progress and mode of delivery (author's transl)].

This randomised study of 611 deliveries deals with the side effects of a modified extradural analgesic technique. The modification is based on a flexible reduction of local anaesthetic concentration (bupivacaine) which allows a reliable analgesia without a marked loss of labour sensation and bearing down reflex. Randomisation was achieved by offering this analgesia to the parturients in an alternating 24 hours rhythm. Statistical comparisons were carried out for the following groups of deliveries: 1. for deliveries on both of the two alternating days (Group A). 2. for deliveries with and without extradural analgesia of the peridural days (Group B). - 3. for all deliveries with and without extradural analgesia (Group C). - 4. For deliveries without extradural analgesia on "peridural days" and on "alternating days" (Group D). - The main subjects of investigation were the duration of the two stages of delivery, the dynamics of both the cervical dilation and the movement of the fetal head and the frequency, modes and causes of operative and instrumental deliveries. The safety of the analgesic technique was investigated by evaluating its influence on the status of the newborn and on the maternal regulation of body temperature and circulation. The results were obtained as follows: 1. In the group of parturients who had chosen extradural analgesia several antenatal factors accumulated which evidently had a greater influence on the course of delivery than the analgesic technique itself. - 2. The low concentration of local anaesthetic adapted to the labour pain produced a sufficient analgesia in almost every case. - 3. The duration of both stages of delivery was not altered directly by this technique. An average increase of the duration of the second stage by 116 minutes was due to postponed indications of instrumental and operative deliveries by analgesia. - 4. There was no influence on the overall frequency of operative and instrumental deliveries. Extradural analgesia, however, significantly reduced the frequency of caesarean sections to the same extent as it increased instrumental deliveries from the bottom of the pelvis. - 5. The extradural analgesia had no influence on the status of the newborn. - 6. The regulatory mechanisms of circulation and body temperature were not altered by this dosage of extradural analgesia.

Adult↗
PubMed1991

Drug delivery systems 5A. Oral drug delivery.

The two main advantages of controlled drug delivery systems are: maintenance of therapeutically optimum drug concentrations in the plasma through zero-order release without significant fluctuations; and elimination of the need for frequent single dose administrations. The oral and other therapeutic systems in human use have validated the concept that controlled continuous drug release can minimize the daily dose of a drug required to maintain the required therapeutic effect, while minimizing unwanted pharmacological effects. By minimizing patient intervention, a design feature of therapeutic systems, compliance is automatically enhanced. Oral drug delivery systems, in particular, have required innovation in materials science to provide materials biocompatible during prolonged contact with body tissues, bioengineering to develop drug delivery modules, and clinical pharmacology for elucidation of drug action under conditions of continuous controlled drug administration. Recent work in advanced oral delivery has been primarily focused on liposome technology and the concept that substances that are normally destroyed by the stomach can be protected long enough before they could be absorbed downstream. For cost and patient convenience, oral delivery certainly would be an attractive method. The nature of biologic substances, however, with their unique technical problems, will probably limit greatly those that can be delivered orally. Besides, where delivery rate control is critical, oral delivery, even when possible, would probably be insufficiently precise. Oral delivery would also limit the substance to bloodstream delivery to the disease site. Even so, oral controlled drug delivery systems will likely find primary usefulness in specific carefully controlled therapies and prophylactic situations with due regard for drug interactions. This system represents a potentially very significant therapeutic modality. These delivery systems will find usefulness primarily in certain well-defined and well-controllable areas with due regard for individual patient variations. The purpose of the present article is to review oral controlled-release drug delivery systems, with particular emphasis on the practical aspects of testing and fabricating these systems and the underlying mechanisms by which control over drug release rate is accomplished.

Administration, Oral↗
PubMed1988

The intraperitoneal delivery of radiolabeled monoclonal antibodies: studies on the regional delivery advantage.

The i.p. delivery of murine monoclonal antibody was compared with i.v. delivery in normal mice and rats, in normal nude mice and in those with i.p. human ovarian carcinoma xenografts. In normal rats, all classes of antibodies and antibody fragments evaluated were cleared from the peritoneal cavity at comparable rates. The regional delivery (Rd1) advantage to the peritoneal cavity following i.p. delivery was thus most dependent on the rate of clearance of the antibody or fragment from the blood stream. Determining the exact i.p. delivery advantage was problematic due to the difficulty in reliably obtaining peritoneal fluid later than 9-10 h after i.p. injection in normal animals. During the first 9 h following i.p. injection, the Rd(0-9/0-9) was, for a murine IgG2ak Fab greater than F(ab')2 greater than IgG (at 13.6 greater than 10 greater than 7.9). Two murine IgMs evaluated differed in Rd(0-9) at 27.1 and 9.2 respectively. When blood levels were extrapolated to infinity, these Rd (0-9/affinity) values were considerably lower with the Fab having the highest Rd at 4.67. The i.p. Rd advantage was almost solely due to the i.p. antibody levels seen in the first 24 h after injection, as after that time, blood levels become comparable to those seen following i.v. injection. Normal tissues obtained at sacrifice 5-7 days after i.p. injection. Normal tissues obtained at sacrifice 5-7 days after i.p. or i.v. injection in rats showed comparable levels of radioantibody activity, whether the injection was i.p. or i.v. (except for higher diaphragmatic levels following i.p. delivery). In nude mice with i.p. human-derived ovarian tumors, intact IgG clearance from the peritoneal cavity to the blood was considerably slower than in normal animals, and early i.p. tumor uptake of specific antibody was significantly higher than that following i.v. antibody delivery. With higher early tumor uptake and lower systemic exposure, early tumor/nontumor ratios were significantly greater than those for i.v. delivery, though not beyond 48 h after i.p. injection. This study demonstrates the pharmacokinetic rationale for i.p. monoclonal antibody delivery, especially for agents cleared rapidly from the blood, such as antibody fragments. In addition, definite i.p. delivery benefit for antibody specific to i.p. tumors in the i.p. ovarian cancer system was shown soon after injection. These data regarding i.p. antibody delivery should be useful in rationally planning diagnostic and therapeutic studies involving the i.p. delivery of unmodified and immunoconjugated monoclonal antibodies.

Animals↗
PubMed2005

Intravenous delivery of liposome-mediated nonviral DNA is less toxic than intraperitoneal delivery in mice.

Suicide gene therapy has been shown to be an effective means of destroying pancreatic cancer cells. Liposomes have been described as having better efficacy in gene delivery, and an advantage of using liposomes as gene carriers is that they can be used repeatedly in vivo. The objective of this study is to compare the effect of gene delivery routes and to determine whether systemic delivery of the rat insulin promoter (RIP)-directed suicide gene construct would permit cell-specific gene delivery in vivo. Severe combined immunodeficient (SCID) mice were injected with liposome-RIP-TK (thymidine kinase) complex by either the intraperitoneal or the intravenous route. Twenty-four hours post gene delivery, mice received ganciclovir (GCV) treatment twice daily for 14 days. Mice were sacrificed at various time points. Complete necropsy and serum chemistry analysis were performed. Islet morphology was determined using hematoxylin and eosin (H&E) staining. Serum glucose and insulin levels were also determined. To determine the toxic effect on pancreatic islet cells, immunostaining of insulin-producing and glucagon-producing cells was carried out at each time point. H&E staining indicated that both intravenous and intraperitoneal liposome-RIP-TK gene expression had no effect in normal endocrine islet cells. Both gene-delivery routes in mice resulted in normal glycemia and serum insulin levels. The endocrine islets were intact, with a normal distribution pattern of insulin-producing beta cells and glucagon-secreting alpha cells. However, serum chemistry analysis revealed significantly elevated levels of liver enzymes; suggesting that possible liver damage had occurred with the intraperitoneal gene delivery of liposome-pRIP-TK. Intravenous liposome-mediated gene delivery had no effect on liver enzyme levels. Liposome-mediated gene delivery via intravenous injection was less toxic than intraperitoneal delivery. This gene-delivery route requires fewer liposome-DNA complexes and maintains normal liver function. Thus, intravenous delivery of gene therapy would be superior to intraperitoneal administration of gene therapy in mice.

Animals↗
PubMed2004

Occurrence and predictors of cesarean delivery for the second twin after vaginal delivery of the first twin.

OBJECTIVE: To estimate the occurrence and to assess clinical predictors of emergent cesarean delivery in the second twin after vaginal delivery of the first twin. METHODS: We conducted a population-based cohort study, using the 1995-1997 linked mother/infant twin data from the United States. The adjusted risk ratios and population attributable risks of clinical predictors of emergent cesarean delivery in second twins were estimated for the overall study sample and for those born at less than 36 or 36 weeks or more of gestation. RESULTS: Among the 61,845 second twin births with the first twin delivered vaginally, 5,842 (9.45%) were delivered by cesarean. The cesarean delivery rate was increased in infants born to mothers with medical or labor and delivery complications. Breech and other malpresentations were the most important predictors of emergent cesarean delivery for the second twin (population attributable risk 33.2%; 95% confidence interval 31.8%, 34.6%). Operative vaginal delivery of the first twin was associated with a decreased risk of cesarean delivery for the second twin. Prediction of emergent cesarean for the second twin by clinical factors was stronger in term births than preterm births. CONCLUSION: In the general population, the cesarean delivery rate for the second twin after vaginal delivery of the first twin is approximately 9.5%. With the presence of breech and other malpresentations, the need for emergent cesarean delivery of the second twin after vaginal delivery of the first twin is increased by 4-fold. LEVEL OF EVIDENCE: II-2

Adult↗
PubMedDate not supplied

Cervical inflammation and preterm delivery in pregnant women with a history of preterm delivery.

BACKGROUND: A previous preterm delivery is a risk factor for preterm delivery in a subsequent pregnancy. We tested the hypothesis that evidence of inflammation on a Papanicolaou smear obtained during pregnancy is a risk factor for preterm delivery for women with a history of preterm delivery. METHODS: We studied women who had two singleton deliveries at a university hospital during an 8-year period. Women eligible for our study were those whose first delivery was preterm (< 37 weeks of gestation) and for whom a Papanicolaou smear was obtained during the second pregnancy. These smears were examined for evidence of inflammation by a cytopathologist. Information about the second pregnancy was obtained by chart review. RESULTS: The cytopathologist reviewed Papanicolaou smears from 92 study pregnancies and found evidence of cervical inflammation on 34 smears (37 percent). Preterm delivery ended 24 (26.1 percent) of the second pregnancies. The incidence of preterm delivery in women with inflammation on Papanicolaou smear was 41.2 percent compared with an incidence of 17.2 percent in women without inflammation (relative risk of 2.40 with a 95 percent confidence interval of 1.19 to 4.83). This association remained significant after controlling for potential confounding variables. A stratified analysis found that the association of cervical inflammation with preterm delivery was limited to women who had systemic exposure to an antibiotic during pregnancy. CONCLUSION: Among pregnant women with a history of preterm delivery, evidence of inflammation on Papanicolaou smear was associated with an increased risk of preterm delivery. If replicated in other studies, this finding might have implications for the management of pregnancies in women with a history of preterm delivery.

Adult↗
PubMed2006

Impact of fetal blood sampling on vaginal delivery and neonatal outcome in deliveries complicated by pathologic fetal heart rate: a population based cohort study.

OBJECTIVE: To compare the impact of electronic fetal monitoring (EFM) alone vs. EFM with additional fetal blood sampling (FBS) in vaginal deliveries complicated by pathologic fetal heart rate (FHR). METHODS: All deliveries in Hesse between 1990 and 2000 were evaluated for participation in this study. Inclusion criteria comprised (1) pathologic fetal heart rate, (2) singleton pregnancy, (3) cephalic presentation, (4) vaginal delivery, and (5) gestational age at delivery of more than 35 weeks' gestation. In order to analyze the meaning of additional risk factors at birth for the effectiveness of FBS two subgroups were selected depending on the presence of additional risk factors at birth. To examine the impact of FBS in deliveries with pathologic FHR on the mode of delivery and on neonatal outcome, univariate regression analysis was performed and odds ratios (OR) and their corresponding 95% confidence intervals (95% CI) were calculated. RESULTS: The study population comprised 49,560 deliveries, among deliveries complicated by pathologic FHR, 26% underwent FBS. Deliveries with pathologic FHR and controlled by FBS, with no additional antepartum risk factors, were associated with an increase in spontaneous births OR 1.41 (95% CI 1.27-1.58), and in the presence of additional risk factors OR 1.24 (1.19-1.30). Short-term neonatal outcome parameters were characterized by a lower frequency of severe fetal acidosis (umbilical artery pH <7.0) OR 0.55 (0.42-0.72), and Apgar score <5 after 5 min, OR 0.71 (0.55-0.90). CONCLUSION: In vaginal deliveries with pathologic FHR the use of FBS as an additional means of intrapartum fetal surveillance is associated with less vaginal operative deliveries, and with an improved short-term neonatal outcome.

Blood Chemical Analysis↗
PubMed2002

What is a reasonable time from decision-to-delivery by caesarean section? Evidence from 415 deliveries.

OBJECTIVE: To determine how long it takes from the decision to achieve delivery by non-elective caesarean section (DDI), the influences on this interval, and the impact on neonatal condition at birth. DESIGN: Twelve months prospective data collection on all non-elective caesarean sections. METHODS: Prospective collection of data relating to all caesarean sections in 1996 in a major teaching hospital obstetric unit was conducted, without the knowledge of the other clinicians providing clinical care. Details of the indication for section, the day and time of the decision and the interval till delivery were recorded as well as the seniority of the surgeon, and condition of the baby at birth. RESULTS: The mean time from decision-to-delivery for 100 emergency intrapartum caesarean sections was 42.9 minutes for fetal distress and 71.1 minutes for 230 without fetal distress (P < 0.0001). For 22 'crash' sections the mean time from decision-to-delivery was 27.4 minutes; for 13 urgent antepartum deliveries for fetal reasons it was 124.7 minutes and for 21 with maternal reasons it was 97.4 minutes. The seniority of the surgeon managing the patient did not appear to influence the interval, nor did the time of day or day of the week when the delivery occurred. Intrapartum sections were quicker the more advanced the labour, and general anaesthesia was associated with shorter intervals than regional anaesthesia for emergency caesarean section for fetal distress (P < 0.001). Babies born within one hour of the decision tended to be more acidaemic than those born later, irrespective of the indication for delivery. Babies tended to be in better condition when a time from decision-to-delivery was not recorded than those for whom the information had been recorded. CONCLUSION: Fewer than 40% intrapartum deliveries by caesarean section for fetal distress were achieved within 30 minutes of the decision, despite that being the unit standard. There was, however, no evidence to indicate that overall an interval up to 120 minutes was detrimental to the neonate unless the delivery was a 'crash' caesarean section. These data thus do not provide evidence to sustain the recommendation of a standard of 30 minutes for intrapartum delivery by caesarean section.

Adult↗
PubMed2004

Neonatal respiratory morbidity risk and mode of delivery at term: influence of timing of elective caesarean delivery.

AIM: To establish whether the timing of delivery between 37 + 0 and 41 + 6 wk gestation influences neonatal respiratory outcome in elective caesarean delivery, following uncomplicated pregnancy, thus providing information that can be used to aid planning of elective delivery at term. METHODS: All pregnant women who were delivered by elective caesarean delivery at term during a 3-y period were identified from a perinatal database and compared retrospectively with pregnant women matched for week of gestation, who were vaginally delivered. Maternal characteristics, neonatal outcome, incidence of respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN) were analysed. During this time, 1284 elective caesarean section deliveries occurred at or after 37 + 0 wk of gestation. RESULTS: Neonatal respiratory morbidity risk (odds ratio, OR), including RDS and TTN, was significantly higher in the infant group delivered by elective caesarean delivery compared with vaginal delivery (OR 2.6; 95% CI: 1.35-5.9; p < 0.01). While TTN risk in caesarean delivery was not increased (OR 1.19; 95% CI: 0.58-2.4; p > 0.05), the RDS risk was significantly increased (OR 5.85; 95% CI: 2.27-32.4; p < 0.01). This RDS risk is greatly increased in weeks 37 + 0 to 38 + 6 (OR 12.9; 95% CI: 3.57-35.53; p < 0.01). After 39 + 0 wk, there was no significant difference in RDS risk. CONCLUSIONS: Infants born by elective caesarean delivery at term are at increased risk for developing respiratory disorders compared with those born by vaginal delivery. A significant reduction in neonatal RDS would be obtained if elective caesarean delivery were performed after 39 + 0 gestational weeks of pregnancy.

Cesarean Section↗
PubMed1999

Increased Intramural Retention After Local Delivery of Molecules with Increased Binding Properties: Implications for Regional Delivery of Pharmacologic Agents.

BACKGROUND: Catheter-based local vascular delivery results in concentrated qualtities of pharmaceutical agents or genes into focal areas of the arterial wall. However, intramural retention is short and has reduced the potential efficacy of this approach. It was postulated that agents that possess increased intramural binding would show increased intramural retention. Platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) were models of agents with increased cellular and extracellular matrix binding properties. METHODS AND RESULTS: The delivery efficiency and intramural retention of 2 mL of saline containing I(125) labeled PDGF (n = 35 arteries) and bFGF (n = 24) were compared with albumin (n = 21) after local delivery into porcine coronary arteries. Animals were sacrificed at three or more prespecified timepoints: immediately after delivery, 1 day, or 3 days after delivery and if necessary at 5 or 7 days to document prolonged retention. Autoradiograms of the arterial sections were evaluated for the extent of delivery. Delivery efficiency, defined as the amount leaving the catheter and retrieved from the arterial wall, was 0.60% +/- 0.42% for albumin, 1.98% +/- 0.88% for PDGF (P =.001), and 0.31% +/- 0.11% for bFGF. The calculated intramural half-life of albumin was 7.4 hours, 56.2 hours for PDGF, and 14.9 hours for bFGF (P =.0001 for PDGF). Infusate covering >50% of the medial area was observed in 85% of arteries immediately after delivery. Although myocardial delivery was similar for albumin, PDGF, and bFGF, myocardial retention was significantlylonger for bFGF (P <.001). CONCLUSIONS: Molecules that exhibit preferential intramural binding show a longer intramural residence duration than solutes without such binding properties. In addition, delivery and subsequent prolonged retention in the myocardium can be obtained by local delivery via the arterial lumen of solutions with preferential binding properties.

Journal Article↗
PubMed1995

Local delivery of biodegradable microparticles containing colchicine or a colchicine analogue: effects on restenosis and implications for catheter-based drug delivery.

OBJECTIVES: This study sought to evaluate the delivery efficiency, intramural retention and antirestenotic efficacy of soluble colchicine or colchicine analogue delivered into the arterial wall after angioplasty as well as the efficacy of these medications after prolonged local release from biodegradable microparticles. BACKGROUND: Local delivery of pharmacologic agents is a potential treatment for restenosis. However, the delivery efficiency of the technique and the choice of agent to modulate cellular proliferation are unknown. It was hypothesized that restenosis would be unaffected by colchicine or a hydrophobic colchicine analogue with short intramural retention, whereas it would be reduced after prolonged local release. METHODS: Rabbit atherosclerotic femoral arteries underwent angioplasty followed by local delivery. Delivery efficiency and intramural retention of 3H-colchicine were evaluated. The effect of agents in soluble formulation or released from microparticles on angiographic and morphometric restenosis was evaluated at 2 weeks and compared with that in the control groups (angioplasty only and local infusion of carrier solution). RESULTS: Delivery of efficiency was 0.01% and intramural retention < 24 h. Neither soluble colchicine formulation reduced restenosis. Microparticles releasing the colchicine analogue reduced restenosis compared with control and colchicine microparticles but not angioplasty alone (p = 0.002). Delivery outside the artery was observed, and the long-term release of both colchicine resulted in toxicity to the adjacent musculature. CONCLUSIONS: Colchicine or the colchicine analogue did not reduce restenosis, although the long-term local release of the colchicine analogue reduced neointimal proliferation resulting from local delivery. Local delivery of cytotoxic agents with insufficient vascular specificity may be limited by toxicity to adjacent tissues resulting from a larger than expected delivery area and prolonged agent retention.

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