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.     

Epidural analgesia during labor

Epidural analgesia is a commonly employed technique of providing pain relief during labor. The number of parturients given intrapartum epidural analgesia is reported to be over 50 percent at many institutions in the United States. The procedure has few contraindications, the primary ones being patient refusal, maternal hemorrhage and coagulopathy. Induction of epidural analgesia in early labor remains controversial. However, many physicians induce analgesia as soon as the diagnosis of active labor has been established and the patient has requested pain relief. The most common complications occurring with epidural analgesia are maternal hypotension and postdural puncture headache. Retrospective studies have demonstrated an association between epidural analgesia and increases in duration of labor, instrumental vaginal delivery and cesarean section for labor. However, several recent prospective studies have concluded that epidural analgesia does not adversely affect the progress of labor or increase the rate of cesarean section. These remain controversial issues among practicing physicians.     

The comparative effects of postoperative analgesic therapies on pulmonary outcome: cumulative meta-analyses of randomized, controlled trials

We performed meta-analyses of randomized, control trials to assess the effects of seven analgesic therapies on postoperative pulmonary function after a variety of procedures: epidural opioid, epidural local anesthetic, epidural opioid with local anesthetic, thoracic versus lumbar epidural opioid, intercostal nerve block, wound infiltration with local anesthetic, and intrapleural local anesthetic. Measures of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), vital capacity (VC), peak expiratory flow rate (PEFR), PaO2, and incidence of atelectasis, pulmonary infection, and pulmonary complications overall were analyzed. Compared with systemic opioids, epidural opioids decreased the incidence of atelectasis (risk ratio [RR] 0.53, 95% confidence interval [CI] 0.33-0.85) and had a weak tendency to reduce the incidence of pulmonary infections (RR 0.53, 95% CI 0.18-1.53) and pulmonary complications overall (RR 0.51, 95% CI 0.20-1.33). Epidural local anesthetics increased PaO2 (difference 4.56 mm Hg, 95% CI 0.058-9.075) and decreased the incidence of pulmonary infections (RR 0.36, 95% CI 0.21-0.65) and pulmonary complications overall (RR 0.58, 95% CI 0.42-0.80) compared with systemic opioids. Intercostal nerve blockade tends to improve pulmonary outcome measures (incidence of atelectasis: RR 0.65, 95% CI 0.27-1.57, incidence of pulmonary complications overall: RR 0.47, 95% CI 0.18-1.22), but these differences did not achieve statistical significance. There were no clinically or statistically significant differences in the surrogate measures of pulmonary function (FEV1, FVC, and PEFR). These analyses support the utility of epidural analgesia for reducing postoperative pulmonary morbidity but do not support the use of surrogate measures of pulmonary outcome as predictors or determinants of pulmonary morbidity in postoperative patients. IMPLICATIONS: When individual trials are unable to produce significant results, it is often because of insufficient patient numbers. It may be impossible for a single institution to study enough patients. Meta-analysis is a useful tool for combining the data from multiple trials to increase the patient numbers. These meta-analyses confirm that postoperative epidural pain control can significantly decrease the incidence of pulmonary morbidity.     

Peridural anesthesia versus subarachnoid anesthesia in cesarean section. Prospective clinical study

OBJECTIVE: To compare technical and clinical differences between epidural and spinal anesthesia for cesarean section. STUDY DESIGN: Randomized prospective trial. PATIENTS AND METHODS: 64 pregnant women at term scheduled for elective cesarean section. Two groups were randomized: A) PD Group (n = 32): continuous epidural anesthesia by administration of bupivacaine 0.5% plus epinephrine 1/400,000 via an epidural catheter. Epidural morphine 3 mg was administered at the end of surgery. B) SP Group (n = 32): "single shot" spinal anesthesia by intrathecal administration of hyperbaric 1% bupivacaine 1-1.4 ml plus morphine 0.2 mg. The pin prick block level reached T2-T6 at incision time. DATA COLLECTION: 1) Time from the beginning of anesthesia to surgical incision. 2) Hypotension episodes. 3) Ephedrine consumption. 4) Intraoperative discomfort at delivery, traction and uterine manipulation, peritoneal toilette. 5) Nausea and vomiting. 6) Apgar score. 7) Postoperative headache. RESULTS: Women in the SP group had more hypotensive episodes (81% vs 53%: p < 0.05) and more ephedrine consumption with a large individual variability (29.12 mg +/- 20.4 vs 12.83 +/- 13.8: p < 0.01) when compared to PD group, without any difference in the Apgar score. The SP group required less time consumption (10.5 min. +/- 6.7 vs 35.9 min. +/- 17.3: p < 0.01) and had less intraoperative discomfort with less analgesic and/or sedative drugs consumption (9.7% vs 29%: p < 0.05) and less vomiting (3% vs 22.5%: p < 0.05). No postoperative headache was noticed in both groups. CONCLUSIONS: With the described pharmacological and technical approach, spinal anesthesia is more suitable than continuous epidural technique for cesarean section, unless contraindicated.     

Higher rate of fetal acidemia after regional anesthesia for elective cesarean delivery

OBJECTIVE: To determine the prevalence of fetal acidemia associated with regional anesthesia for elective cesarean delivery in healthy paturients with uncomplicated singleton term pregnancies. METHODS: This was an epidemiologic study using the data base of the Swiss obstetric study group (Arbeitsgemeinschaft Schweizerischer Frauenkliniken). After the exclusion of cases with extraneous factors that may have affected the health of the neonate, we analyzed the umbilical artery pH, Apgar score, and other neonatal outcome measures after cesarean delivery with reference to the anesthetic technique. RESULTS: From 1985 to 1994, 327,763 deliveries, including 40,858 (12.47%) by cesarean, were registered in the data base. Of these, 5806 patients fulfilled the study criteria. The study population included 1002 spinal, 2155 epidural, and 2649 cases of general anesthesia. The frequency of fetal acidemia (pH less than 7.10) was significantly increased in the spinal-anesthesia group (odds ratio [OR] 4.67; 95% confidence interval [CI] 2.73, 8.01) and in the epidural group (OR 2.39; 95% CI 1.42, 4.04) compared with the general-anesthesia group. CONCLUSION: The rate of fetal acidemia is significantly increased after regional anesthesia. This risk must be judged in light of the risks inherent with general anesthesia.     

Epidural fentanyl, adrenaline and clonidine as adjuvants to local anaesthetics for surgical analgesia: meta-analyses of analgesia and side-effects

BACKGROUND: The risk/benefit ratio of adding fentanyl, adrenaline and clonidine to epidural local anaesthetics for improving intraoperative analgesia is unclear. This meta-analysis was performed to clarify this issue. METHODS: Trials retrieved by search were considered if they were prospective, controlled, epidural analgesia (without combining general anaesthesia) was planned and occurrence of pain during surgery or side-effects were reported. Papers entered meta-analysis if they reached a predefined minimum quality score. Pooled odds ratios (OR) and confidence intervals (CI) were computed. P < 0.05 was considered as significant. RESULTS: Eighteen trials were included in the analysis for fentanyl. Fentanyl decreased the likelihood of pain (OR = 0.21, 95% CI = 0.15-0.30, P < 0.001) and increased the incidence of pruritus (OR = 5.59, 95% CI = 3.12-10.05, P < 0.001) and sedation (OR = 1.88, 95% CI = 1.19-2.98, P = 0.003), compared to control (local anaesthetic without fentanyl). Fentanyl had no effect on respiratory depression, nausea, vomiting and Apgar score. One case of respiratory depression of a newborn was observed. Because of the very low number of trials selected, evaluation of adrenaline and clonidine was not feasible. CONCLUSION: The analysis of current literature shows that the addition of fentanyl to local anaesthetics for intraoperative epidural analgesia is safe and advantageous. The reduction in the incidence of pain during surgery is quantitatively high and therefore clinically significant. Side-effects are mild. Randomized, controlled trials have to be performed in order to clarify the role of adrenaline and clonidine as epidural adjuvants for surgical analgesia.     

Streptokinase in acute stroke: effect on reperfusion and recanalization. Australian Streptokinase Trial Study Group

BACKGROUND: The minimum local analgesic concentration (MLAC) has been defined as the median effective local analgesic concentration in a 20-ml volume for epidural analgesia in the first stage of labor. The aim of this study was to determine the local anesthetic-sparing efficacy of epidural sufentanil by its effect on the MLAC of bupivacaine. METHODS: In this double-blind, randomized, prospective study, 147 parturients at < or = 7 cm cervical dilation who requested epidural analgesia were allocated to one of four study groups. After a lumbar epidural catheter was placed, study participants received 20 ml bupivacaine (n = 38), bupivacaine with sufentanil 0.5 microg/ml (n = 38), bupivacaine with sufentanil 1 microg/ml (n = 33), or bupivacaine with sufentanil 1.5 microg/ml (n = 38). The concentration of bupivacaine was determined by the response of the previous patient using up-down sequential allocation. The analgesic efficacy was assessed using 100-mm visual analog pain scores, with < or = 10 mm within 30 min defined as effective. RESULTS: The MLAC of bupivacaine alone was 0.104% wt/vol (95% CI, 0.090-0.117). The addition of sufentanil at doses of 0.5 microg/ml, 1 microg/ml, and 1.5 microg/ml resulted in significant reductions (P < 0.0001) in the MLAC of bupivacaine to 0.048% wt/vol (95% CI, 0.030- 0.065), 0.021% wt/vol (95% CI, 0-0.055), and 0.009% wt/vol (95% CI, 0-0.023), respectively. CONCLUSIONS: This study showed a significant (P < 0.0001) dose-dependent reduction in the MLAC ofbupivacaine by sufentanil.     

Biological control of nematode parasites of livestock in Fiji: screening of fresh dung of small ruminants for the presence of nematophagous fungi

OBJECTIVE: To assess risk factors and outcomes associated with nuchal cord at birth. STUDY DESIGN: A population-based, case-control study was conducted using linked birth and hospitalization records. Three thousand newborns were randomly selected from all singleton births with nuchal cord as noted on the birth record (n = 5,426) in King County, Washington, 1992-1993. For comparison, 3,000 controls were randomly selected from the 46,952 unaffected singleton births. RESULTS: An increased risk of nuchal cord was associated with induction of labor (odds ratio [OR] adjusted for maternal age and parity 2.0, 95% confidence interval [CI] 1.7-2.3), African American infant race (OR 1.3, 95% CI 1.0-1.6), primiparity (OR 1.2, 95% CI 1.0-1.5) and male sex (OR 1.2, 95% CI 1.0-1.3). After exclusion of selected obstetric complications, the risk of nuchal cord associated with induction of labor increased (OR 2.4, 95% CI 2.0-3.0). Nuchal cord was associated with increased risks of fetal distress (OR 2.7, 95% CI 2.1-3.4), meconium staining (OR 2.1, 95% CI 1.7-2.6), five-minute Apgar score < 7 (OR 1.6, 95% CI 1.1-2.4) and assisted ventilation < 30 minutes (OR 1.9, 95% CI 1.4-2.6). Although hospital charges for newborns with nuchal cord were slightly greater than for those without (P = .02), hospital lengths of stay did not differ significantly. CONCLUSION: Induction of labor was identified as an independent risk factor for nuchal cord. Certain adverse perinatal outcomes are increased in neonates with nuchal cord. However, neonates with nuchal cord do not have significantly longer neonatal hospital stays, and thus the adverse effects of nuchal cord may be transient.     

Epidural fentanyl produces labor analgesia by a spinal mechanism

BACKGROUND: The purpose of this study was to determine if epidural fentanyl produces analgesia in laboring patients by a primary spinal or supraspinal action. METHODS: Fifty-four parturients were randomized to receive epidural 0.125% bupivacaine plus one of three treatments: epidural saline-intravenous saline, epidural fentanyl (20 microg/h)-intravenous saline, or epidural saline-intravenous fentanyl (20 microg/h). The study treatments were administered by continuous infusion, whereas epidural bupivacaine use was patient controlled. RESULTS: Epidural bupivacaine use was significantly reduced by epidural (11.5+/-4.6 ml/h) but not by intravenous fentanyl (15.9+/-4.5 ml/h) compared with saline control (16+/-5.9 ml/ h). Analgesia characteristics and side effects were similar among groups. CONCLUSIONS: Low-dose epidural infusions of fentanyl produce labor analgesia by a primary spinal action.     

Comparison of 0.25% ropivacaine and bupivacaine for epidural analgesia for labor and vaginal delivery

STUDY OBJECTIVE: Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects. DESIGN: Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study. SETTING: Labor and delivery units of two academic hospitals. PATIENTS: Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor. INTERVENTIONS: For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours. MEASUREMENTS AND MAIN RESULTS: For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 +/- 0.14 microgram/ml and 0.10 +/- .02 microgram/ml, respectively; the umbilical venous total and free concentrations were 0.19 +/- 0.03 microgram/ml and 0.12 +/- 0.07 microgram/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.05) than the bupivacaine group. CONCLUSION: Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate.     

Severe preeclampsia remote from term: labor induction or elective cesarean delivery?

OBJECTIVES: The study's objectives were as follows: (1) to determine the rate of vaginal delivery after labor induction in severe preeclampsia remote from term and (2) to determine potential predictors of success. STUDY DESIGN: Retrospective chart review was conducted on live-born singleton pregnancies complicated by severe preeclampsia and delivered at 24 to 34 weeks' gestation from January 1, 1992, to December 31, 1996. Exclusion criteria included eclampsia, presence of labor or spontaneous rupture of membranes on admission, and complication of pregnancy by an ultrasonographically detected fetal congenital anomaly. Patients were divided into 3 groups: elective cesarean delivery without labor, cesarean delivery after labor induction, and vaginal delivery after labor induction. Statistical analyses included multiple logistic regression, the Student t test, the chi2 test, and the Mann-Whitney test. P 32 weeks' gestation. The most common indication for cesarean delivery after induction, in 50.7% of the cases, was nonreassuring fetal heart rate. The median Bishop score was significantly higher (3 vs 2, P =.004) and the total hospital stay was significantly shorter in the vaginal delivery after induction group than in the cesarean delivery after induction group. However, there were no significant differences between the 2 groups in use of cervical ripening agents, gestational age at delivery, birth weight, 5-minute Apgar score, or postpartum endometritis. After exclusion of cesarean deliveries performed for malpresentation, there was no statistically significant difference in classic incision rates between the elective cesarean delivery without labor and cesarean delivery after induction groups (13.6% vs 6.8%; P =.137). According to logistic regression analysis, only the Bishop score was significantly associated with a successful induction (odds ratio 1.38, 95% confidence interval 1.11-1.71). Gestational age reached marginal significance (odds ratio 1.30, 95% confidence interval 0.89-1.89). CONCLUSIONS: (1) Labor induction should be considered a reasonable option for patients with severe preeclampsia at 相似文献   

Delayed childbearing--are there any risks?

OBJECTIVE: To determine whether women delivering their first child at age 35 years or older are at increased risk of adverse (non-genetic) pregnancy outcomes. DESIGN AND SETTING: A cross-sectional analytic study of singleton deliveries in Northern Sydney Area Health Service (NSAHS) hospitals. PARTICIPANTS: All women aged > or = 20 years delivering their first child between 1 January 1990 and 31 December 1991. MAIN OUTCOME MEASURES: Obstetric complications and procedures, type of delivery and neonatal outcomes. RESULTS: Compared with women aged 20-29 years, women delivering their first child at > or = 35 years were at increased risk of pre-existing maternal hypertension (adjusted odds ratio [OR], 3.5; 95% confidence interval [CI], 1.7-7.0), antepartum haemorrhage (adjusted OR, 2.4; 95% CI, 1.6-3.7), preterm delivery (33-36 weeks) (adjusted OR, 2.0; 95% CI, 1.5-2.8) and breech presentation (adjusted OR, 1.8; 95% CI, 1.3-2.4). Women aged > or = 35 years were also substantially more likely to have an operative delivery, induced labour and/or epidural anaesthesia. Neither these women nor their infants were at increased risk of pregnancy-induced hypertension, gestational diabetes, threatened premature labour, postpartum haemorrhage, very preterm delivery (< or = 32 weeks), perinatal death, low Apgar scores or the need for neonatal resuscitation. CONCLUSIONS: Women who delay the birth of their first child face some increased risks, but these risks, for the most part, are manageable in the context of modern obstetric care.     

Adrenalectomy for a solitary adrenal metastasis from lung cancer

Intrathecal sufentanil provides approximately 2 h of excellent labor analgesia with minimal motor blockade. Epidural sufentanil has received less scrutiny but may provide the same benefits as intrathecal sufentanil. In this study, we compared epidural sufentanil 40 microg after a lidocaine with an epinephrine test dose with intrathecal (i.t.) sufentanil 10 microg with respect to onset and duration of analgesia, degree of motor block, side effect profile, and mode of delivery. Seventy ASA physical status I or II parturients in early labor (< or = 4 cm cervical dilation) were randomized to receive either i.t. sufentanil 10 microg with a combined spinal-epidural technique (CSE) or epidural sufentanil 40 microg (e.p.) after epidural catheter placement and testing with 3 mL of 1.5% lidocaine with epinephrine (15 microg). After the administration of analgesia, pain scores and side effects were recorded for each patient at 5, 10, 15, 20, and 30 min, and every 30 min thereafter, by an observer blinded to the technique used. The study period was completed when the patients requested additional analgesia. All patients, except one, achieved adequate analgesia with the initial study dose and satisfactorily completed the study. There were no demographic differences between the two groups. Pain relief was rapid for all patients; pain scores were significantly lower at 5 and 10 min in the i.t. group versus the e.p. group. The mean duration of analgesia was similar between the e.p. group (127 +/- 40 min) and the i.t. group (110 +/- 48 min). No patient experienced any motor block. Side effects were similar between the two groups, except for pruritus-both the incidence and severity were significantly more profound at 5, 10, 15, 20, and 30 min in the i.t. group. There was no difference in time from analgesic to delivery, incidence of operative or assisted delivery, or cervical dilation at the time of redose. For early laboring patients, epidural sufentanil 40 microg after a lidocaine test dose provides analgesia comparable to that of i.t. sufentanil 10 microg with less pruritus. Implications: We compared the efficacy and side effects of intrathecal sufentanil with epidural sufentanil with a local anesthetic test dose for analgesia during labor. Analgesia was equally good, although the intrathecal group experienced more itching.     

Obstetric analgesia in Norwegian hospitals]

We report the results of a questionnaire sent to anaesthetists and midwives on the use of obstetric analgesia and anaesthesia in Norwegian hospitals in 1996. 95% of the 49 hospitals involved responded to the questionnaire, representing a total of 56,884 births. The use of epidural analgesia in labour varied from 0 to 25% in the different hospitals with a mean value of 15%. Epidural analgesia was much more widely used in university and regional hospitals than in local hospitals (p < 0.001). Five of the local hospitals did not offer epidural analgesia during labour at all. The combination of low-dose local anaesthetic and an opioid (either sufentanil or fentanyl) had not been introduced in nine of the hospitals (20%). The optimal use of epidural analgesia to relieve labour pain was judged to be more frequent by the anaesthetists than by the midwives (19% versus 11%, p < 0.01). In response to what factors limited the frequency of epidural analgesia, the anaesthetists specified factors related to the attitude of the midwife, and the midwives specified factors related to the anaesthetist. Only five of the hospitals provided written information on the various analgesic methods that could be employed during labour. The majority of midwives considered the analgesic methods employed on their maternity ward to be good or excellent. The frequency of Caesarean section was 12%; spinal anaesthesia was used in 55%, epidural anaesthesia in 17%, and general anaesthesia in 28% of the cases.     

Endoluminal repair of an internal carotid artery pseudoaneurysm

OBJECTIVE: To measure the serum levels of interleukin (IL)-8, prostaglandin (PG) F2alpha, and beta-endorphin in parturients with acupuncture treatment and in controls to clarify the effect of acupuncture and duration of labor on the serum levels of substances active in cervical ripening and dilatation. METHODS: A matched pair study was performed involving 80 women with and without prenatal acupuncture treatment, matched for age and parity. Serum levels of IL-8, PGF2alpha, and beta-endorphin were measured in serum samples taken after delivery by use of enzyme-linked immunosorbent assay, enzyme immunoassay, and immunoradiometric assay, respectively. RESULTS: The mean difference in total duration of labor between matched pairs with and without acupuncture was -136.5 minutes (95% confidence interval [CI] 191.1 minutes, -81.9 minutes; paired t test, P < .001). The mean difference of the duration of the first and second stages of labor between matched pairs with and without acupuncture was -138.8 minutes (95% CI 188.6, -89.0 minutes; paired t test, P < .001) and 2.3 minutes (95% CI 15.5, 20.1 minutes; paired t test, P = .8), respectively. The geometric means of ratios of IL-8, PGF2alpha, and beta-endorphin between matched pairs in women with and without acupuncture showed no statistically significant differences. Serum levels of IL-8, PGF2alpha, and beta-endorphin were not significantly correlated with the duration of the first and second stages of labor. CONCLUSION: Prenatal acupuncture treatment significantly reduces the duration of labor and may be a valuable tool in prenatal preparation. Serum levels of IL-8, PGF2alpha, and beta-endorphin are not significantly influenced by acupuncture and are therefore not likely to mediate acupuncture-related effects during labor.     

Increased risk of placenta previa among women of Asian origin

OBJECTIVE: To investigate the frequency of placenta previa among Asian women. METHODS: We conducted a population-based case-control study using Washington state birth certificate data from 1984-1987. Our study population included 810 women with pregnancies complicated by placenta previa and 2917 randomly selected controls. Unconditional logistic regression was used to estimate odds ratios (OR) and their 95% confidence intervals (CI), and interaction terms were used to examine effect modification. Potential confounding by maternal age, gravidity and parity, maternal smoking during pregnancy, and a history of abortion or cesarean delivery was adjusted for in the analysis. RESULTS: The frequency of placenta previa during the study period was 3.3 per 1000 live births. Women of Asian origin were 86% more likely (OR 1.86, 95% CI 1.38-2.51) to have a delivery complicated by placenta previa than were white women. This association was stronger among women without a previous live birth (OR 2.51, 95% CI 1.57-4.01) than those who previously had experienced a live birth (OR 1.50, 95% CI 1.01-2.25). CONCLUSION: Asian women residing in the United States are at increased risk of placenta previa. If confirmed by others, our results suggest that obstetricians should consider meticulous ultrasound evaluations during pregnancy to rule out the presence of placenta previa in Asian-American women.     

Cytotoxic and ichthyotoxic compounds from marine Opisthobranchia and soft coral

Epidural analgesia in labour using local anaesthetics is very efficient, but the technique has been associated with undesired motor block and an increased use of instrumental deliveries. A new epidural analgesia technique, using a combination of low-dose local anaesthetics and opioids (fentanyl and sufentanil), has recently come into practice. The new epidural technique provides excellent analgesia, minimises motor block, allows the mother to ambulate, and minimises the need for instrumental delivery. Furthermore, it constitutes a good alternative to parenteral pethidine. We are of the opinion that all pregnant women should be given detailed information about both the benefits and the possible side-effects of epidural analgesia in good time before they go into labour. This will allow them to participate more actively in deciding whether or not to use analgesia during labour. Optimal use of epidural analgesia not only depends on the availability of a 24-hour anaesthesia service, but also on adequate knowledge and the cooperation and enthusiasm of all those involved, namely midwives, obstetricians and anaesthesiologists.     

Prognosis and outcomes of patients with community-acquired pneumonia. A meta-analysis

OBJECTIVE: To systematically review the medical literature on the prognosis and outcomes of patients with community-acquired pneumonia (CAP). DATA SOURCES: A MEDLINE literature search of English-language articles involving human subjects and manual reviews of article bibliographies were used to identify studies of prognosis in CAP. STUDY SELECTION: Review of 4573 citations revealed 122 articles (127 unique study cohorts) that reported medical outcomes in adults with CAP. DATA EXTRACTION: Qualitative assessments of studies' patient populations, designs, and patient outcomes were performed. Summary univariate odds ratios (ORs) and rate differences (RDs) and their associated 95% confidence intervals (CIs) were computed to estimate a summary effect size for the association of prognostic factors and mortality. DATA SYNTHESIS: The overall mortality for the 33,148 patients in all 127 study cohorts was 13.7%, ranging from 5.1% for the 2097 hospitalized and ambulatory patients (in six study cohorts) to 36.5% for the 788 intensive care unit patients (in 13 cohorts). Mortality varied by pneumonia etiology, ranging from less than 2% to greater than 30%. Eleven prognostic factors were significantly associated with mortality using both summary ORs and RDs: male sex (OR = 1.3; 95% CI, 1.2 to 1.4), pleuritic chest pain (OR = 0.5; 95% CI, 0.3 to 0.8), hypothermia (OR = 5.0; 95% CI, 2.4 to 10.4), systolic hypotension (OR = 4.8; 95% CI, 2.8 to 8.3), tachypnea (OR = 2.9; 95% CI, 1.7 to 4.9), diabetes mellitus (OR = 1.3; 95% CI, 1.1 to 1.5), neoplastic disease (OR = 2.8; 95% CI, 2.4 to 3.1), neurologic disease (OR = 4.6; 95% CI, 2.3 to 8.9), bacteremia (OR = 2.8; 95% CI, 2.3 to 3.6), leukopenia (OR = 2.5, 95% CI, 1.6 to 3.7), and multilobar radiographic pulmonary infiltrate (OR = 3.1; 95% CI, 1.9 to 5.1). Assessments of other clinically relevant medical outcomes such as morbid complications (41 cohorts), symptoms resolution (seven cohorts), return to work or usual activities (five cohorts), or functional status (one cohort) were infrequently performed. CONCLUSIONS: Mortality for patients hospitalized with CAP was high and was associated with characteristics of the study cohort, pneumonia etiology, and a variety of prognostic factors. Generalization of these findings to all patients with CAP should be made with caution because of insufficient published information on medical outcomes other than mortality in ambulatory patients.     

Sex and reproduction in the nematode C. elegans]

BACKGROUND: An exploratory, case-control study was used to investigate a new hypothesis about suicide among farm operators. This hypothesis suggested a biologically plausible link between exposures to certain pesticides and the occurrence of suicide among farm operators. These analyses were based on data from the Canadian Farm Operator Cohort. METHODS: Canadian male farm operators who committed suicide between 1971-1987 (n = 1,457) were compared with a frequency matched (by age and province) sample of control farm operators (n = 11,656) who were alive at the time of death of individual cases. Comparisons focused on past exposures to pesticides reported to the 1971 Canada Census of Agriculture. RESULTS: Multivariate logistic regression analyses indicated no associations between suicide and (1) acres sprayed with herbicides, (2) acres sprayed with insecticides, and (3) the costs of agricultural chemicals purchased; after controlling for important covariates. There was, however, a suggestive increase in risk for suicide associated with herbicide and insecticide spraying among a subgroup of farm operators who were most likely to be directly exposed to pesticides: OR = 1.71 (95% CI = 1.08-2.71) for 1-48 vs. 0 acres sprayed. Additional risk factors that were identified included seasonal vs. year-round farm work (OR = 1.68; 95% CI = 1.15-2.46); and high levels of paid labor on the farm (e.g., OR = 1.61; 95% CI = 1.24-2.10, for > 13 vs. 0 weeks per year). Factors that were protective included marriage (odds ratio (OR) = 0.69; 95% confidence interval (CI) = 0.58-0.81), having more than one person resident in the farm house (e.g., two vs. one person; OR = 0.62; 95% CI = 0.42-0.92); and higher levels of education (e.g., postsecondary vs. primary; OR = 0.40; 95% CI = 0.17-0.96). CONCLUSIONS: This study does not provide strong support for the main hypothesis under study, that exposure to pesticides is an important risk factor for suicide among farmers. Although secondary to the main hypothesis, a number of other risk factors for suicide were suggested. These have implications for the future study and targeting of suicide prevention programs in rural Canada.