Factors influencing cesarean delivery operative times: a prospective observational cohort study.

BACKGROUND: This study aimed to determine the distribution of operative delivery times for uncomplicated parturients undergoing elective cesarean delivery with neuraxial anesthesia. A secondary aim was to explore patient and surgical factors associated with longer cesarean delivery times. METHODS: A prospective observational study of 331 parturients undergoing elective cesarean delivery with neuraxial anesthesia was conducted. Factors examined included age, body mass index, ethnicity, number of previous cesarean deliveries, stretch mark and scar severity and surgical experience. RESULTS: Operative times ranged from 13 to 108 min with a mean (SD) of 43.4 (±15.7) min. Only 6 (1.8%) parturients had operative times >90 min and none were converted to general anesthesia. As the number of previous cesarean deliveries increased, the mean operative time increased linearly from 39.5 (±13.0) min in subjects with no previous cesarean deliveries to 52.8 (±18.1) min in subjects with 3 or 4 previous cesarean deliveries (P<0.0005). For parturients with previous cesarean deliveries, operative times were longer for those with scar scores > or =5 than for those with scores <5 (P<0.01). Stretch mark scores were not associated with operative times. Tubal ligation prolonged the total operative time by a mean of 7 min (P<0.0005), and attending staff required a mean of 6 more min than residents or fellows (P<0.01). There was no correlation between operative times, age and body mass index and little variation with ethnicity. CONCLUSIONS: These findings identify previous cesarean deliveries, increased scar intensity, tubal ligation and surgical experience as factors that increase operative times for cesarean delivery. The data also suggest that neuraxial anesthesia lasting 90 min should provide adequate analgesia for most uncomplicated parturients undergoing elective cesarean delivery.

Anaphylactoid reaction to intravenous sodium ferric gluconate complex during pregnancy.

We report the first case of a severe anaphylactic or anaphylactoid reaction to sodium ferric gluconate complex in a pregnant patient. Sodium ferric gluconate complex is felt to be one of the safest forms of iron therapy during pregnancy. This case highlights the need for extreme caution and vigilance in pregnant patients receiving any type of parenteral iron therapy.

Increased intrapartum antibiotic administration associated with epidural analgesia in labor.

To determine whether women who receive continuous epidural analgesia for labor and delivery are more likely to receive antibiotic therapy compared to those parturients who do not use epidural analgesia, a chart review was performed for 300 women 100 in each group using narcotics alone epidural alone, or parenteral narcotics followed by epidural analgesia. While only 2% of women with narcotics alone developed an intrapartum temperature > or = 37.8 degrees C, 16% and 24% of women with epidural use alone or in addition to narcotics did so, respectively. Antibiotic administration was increased among women utilizing epidural analgesia, exclusively or following parenteral narcotics. No parturient with culture or pathological evidence of chorioamnionitis had maternal temperature elevation as an isolated finding. A probable causal relationship between maternal temperature elevation and epidural use in labor is supported. Rather than treating all women with temperature elevations and epidurals for presumed chorioamnionitis, it is reasonable to target treatment to those with fetal tachycardia, meconium stained fluid, or abnormal amniotic fluid studies.

Hyperthyroidism and seizures during pregnancy.

Untreated hyperthyroidism during pregnancy is associated with increased maternal and perinatal morbidity. Some features of this disease simulate preeclampsia, which may encourage delivery of the fetus. We report a case of poorly controlled hyperthyroidism associated with generalized seizures, where patient management was directed at a diagnosis of preeclampsia-eclampsia. Although the presence of eclampsia and marked hyperthyroidism is very rare, this case illustrates the importance of aggressive medical management of hyperthyroidism. A 17-year-old gravida was diagnosed with hyperthyroidism at 15 weeks' gestation. At 26 weeks' gestation, she was admitted to the hospital after noting edema of the upper and lower extremities, nausea, vomiting, shortness of breath, and a cough. At admission, she was hypertensive, tachycardic, and dyspneic. The patient was believed to have preeclampsia with pulmonary edema complicated by hyperthyroidism. We initiated magnesium sulfate therapy and administered several bolus doses of hydralazine, with little effect on blood pressure. Oliguria was noted, and a pulmonary artery catheter was inserted. Hours later, generalized seizure activity occurred, and a decision was made for abdominal delivery. Postoperatively, cardiovascular function stabilized. On postoperative day 3, we received the results of the thyroid function tests obtained at admission, which suggested a markedly hyperthyroid condition. Untreated or poorly treated hyperthyroidism may present a clinical picture similar to preeclampsia. In our case, both disease processes coexisted in their severest forms. It is possible, although completely unproven, that a relationship exists between poorly controlled hyperthyroidism and preeclampsia-eclampsia. More importantly, accurate diagnosis of hyperthyroidism should lead to prompt medical or surgical management, thereby decreasing maternal and perinatal morbidity.

Estrogen mediates the pregnancy-enhanced cardiotoxicity of cocaine in the isolated perfused rat heart.

OBJECTIVE: To determine whether pregnancy enhances cocaine toxicity in the isolated perfused whole rat heart model and whether this enhanced toxicity can be simulated by pre-treatment with either estrogen or progesterone. METHODS: Hearts excised from 65 female Sprague-Dawley rats were attached to a Langendorff apparatus for measurement of left ventricular systolic pressure, heart rate, and contractility. Before excision, the animals were assigned to one of five groups: 1) nonpregnant, 2) pregnant, 3) nonpregnant pretreated with progesterone, 4) nonpregnant pretreated with estrogen, and 5) nonpregnant pretreated with estrogen and progesterone. Each group was exposed serially to the following cocaine concentrations: 5 x 10(-6), 1 x 10(-5), and 6 x 10(-5) mol/L. RESULTS: Heart rate declined at all doses of cocaine (9.2, 6.9, and 31.0%, respectively). The lowest dose of cocaine had positive inotropic effects, with a 23.2% increase in left ventricular pressure and a 15.3% increase in contractility. Exposure to the two higher doses resulted in negative inotropic effects (a 24.8% decrease in left ventricular pressure and a 39.7% decrease in contractility for the highest dose). Although pre-treatment with estrogen, alone or with progesterone, resulted in responses similar to those seen in pregnant animals, progesterone pre-treatment alone failed to do so. CONCLUSIONS: Cocaine displayed cardiotoxicity in isolated rat hearts similar to that in other animal models. This toxicity was enhanced by pregnancy. We were able to simulate changes by pretreating the animals with estrogen. Perhaps the enhanced cardiotoxicity of cocaine in pregnancy is partially mediated by estrogen.

Central hemodynamic effects of cocaine and ritodrine in the isolated, perfused rat heart.

OBJECTIVE: To explore the cardiac interactions of cocaine and ritodrine in pregnancy. METHODS: Using the isolated, perfused rat-heart model, hearts from pregnant Sprague-Dawley rats were exposed to increasing concentrations of ritodrine: 25, 50, 100, and 250 ng/mL. Hearts of half of the animals, the experimental group, were exposed to cocaine (5 x 10(-6) mol/L). Left ventricular systolic pressure, heart rate, and contractility were measured. RESULTS: Ritodrine had marked positive inotropic and chronotropic effects. Cocaine exposure resulted in smaller increases in all indices. CONCLUSION: Cocaine blunted but did not obliterate the cardiac stimulatory effects of ritodrine in this model.

Do nifedipine and verapamil potentiate the cardiac toxicity of magnesium sulfate?

We hypothesized that verapamil and nifedipine would potentiate the cardiac toxicity of magnesium in a dose-dependent manner. The hypothesis was tested in the isolated perfused rat heart model (Langendorff's apparatus) with Sprague-Dawley rats. After excision of hearts, each heart was exposed to increasing doses of verapamil and nifedipine followed by magnesium sulfate. Heart rate, contractility, and left ventricular systolic pressure were measured. Nifedipine and verapamil infusion in this model caused dose-dependent decreases in all three parameters measured (p values 0.05 to 0.01). The addition of magnesium sulfate potentiated these dose-dependent decreases (p values 0.01 to 0.0002). Nifedipine and verapamil caused similar depression at equivalent doses. Nifedipine and verapamil cause dose-dependent cardiac depression that is potentiated by the addition of magnesium sulfate in the isolated perfused rat heart. Caution is called for when magnesium sulfate and calcium channel blockers are administered in combination.

Pregnant patients in the intensive care unit: a descriptive analysis.

We present a descriptive analysis of experience with pregnant women in the intensive care units at a tertiary hospital. During the period from 1983 through 1990, 38 women were admitted to our intensive care units during their pregnancy or within 2 weeks postpartum. This was a rate of 1 per 400 pregnant patients. The mean age of these 38 women was 25 years; 68% of them were white and 32% were primigravidas. Nineteen of the 38 women were mechanically ventilated. Twelve women were admitted for hypertensive disease and 10 for adult respiratory distress syndrome. Maternal mortality was 18% (7/38). Follow-up was available for 33 women. The fetal and neonatal loss rate in this group was 4 of 33 pregnancies. In this case series of 38 very ill women, it was apparent that a team approach of obstetricians, anesthesiologists, and intensive care workers provided optimal management for the mother and child.

The effect of lateral tilt on maternal and fetal hemodynamic variables.

We measured maternal blood pressure and heart rate, fetal heart rate, and umbilical artery velocity waveforms in 25 healthy women placed in the supine and in both right and left 5 degrees and 10 degrees lateral tilt positions. Although we found no significant difference among these variables in the various maternal positions, two of 25 women became hypotensive and symptomatic in the supine and 5 degrees tilt positions. Because we could not predict which women would become symptomatic, we recommend lateral tilt of all pregnant women during operative procedures beyond 20 weeks' gestation, including those in the lithotomy position for vaginal delivery.

Nifedipine enhances the cardiac toxicity of magnesium sulfate in the isolated perfused Sprague-Dawley rat heart.

Magnesium sulfate is commonly used in tocolytic regimens and as prophylaxis against seizures. Nifedipine may be used simultaneously in either situation. With the isolated perfused rat heart model (Sprague-Dawley rats), we investigated the effects of these agents on cardiac function. Whereas each agent alone depressed cardiac performance, the two drugs together had maximal depressive effects on the heart.

Anesthetic management for obstetric hysterectomy: a multi-institutional study.

A prospectively designed review of all obstetric hysterectomies performed in five university hospitals between November 1, 1984 and October 31, 1987 has been performed. There were 41,107 deliveries and 46 obstetric hysterectomies, an incidence of 0.11%. Twenty-five hysterectomies were elective and 21 were emergent. The indication for 11 of the 21 emergency hysterectomies was placenta previa and/or accreta. Women in the emergency group had greater intraoperative blood loss, were more likely to have intraoperative hypotension, and were more likely to receive donor blood than women in the elective group (P less than 0.05). Twelve patients (eight from the elective group and four from the emergency group) received continuous epidural anesthesia, and none required intraoperative induction of general anesthesia. There was no evidence that epidural anesthesia significantly affected blood loss, crystalloid replacement, or requirement for transfusion in the elective group. Abnormal placentation now represents a major indication for emergency obstetric hysterectomy. Furthermore, significant hemorrhage is more likely with emergency obstetric hysterectomy than with elective hysterectomy. Finally, elective cesarean hysterectomy is not a contraindication to performance of continuous epidural anesthesia.

Maternal cardiovascular effects of drugs that alter uterine activity.

All drugs that modify uterine activity have cardiovascular effects. These changes, which include alterations in blood pressure, heart rate, cardiac output, the peripheral vascular resistance, can have significant impact on both mother and fetus. The intensity of these effects is dependent on the concentration of the agent, its infusion rate, and the additive effects of other drugs administered concomitantly. A knowledge of these potentially adverse cardiovascular properties of medications that alter uterine activity is required for competent management of preterm and term labor and delivery.

Cerebrospinal fluid correlates of depression in Huntington's disease.

Patients with Huntington's disease (HD) commonly have concomitant depressive disorders. Prompted by reports of elevated corticotropin releasing factor (CRF) and reduced 5-hydroxyindoleacetic acid (5-HIAA) concentrations in lumbar cerebrospinal fluid (CSF) of patients with major depression, these CSF constituents were examined in 56 nonmedicated patients who were in the early stages of HD. Elevated CRF concentrations were found in patients with HD in comparison with a control group of 21 subjects without neurologic illness. The CSF 5-HIAA concentrations in patients with HD did not differ from that in four normal volunteers. Patients with HD who had depressive disorders (major depression or dysthymia) did not differ from those without depression with respect to CSF 5-HIAA or CRF concentration. However, a positive correlation was observed between severity of major depression and CRF concentration. These findings suggest that the depression associated with HD may differ neurochemically from that seen in other major depressive disorders, and support the notion that clinically significant depressive symptoms reflect heterogeneous pathophysiologic conditions with different neurochemical correlates.

The effect of human amniotic fluid on the isolated perfused rat heart.

To test the hypothesis that amniotic fluid directly affects cardiac function, isolated rat hearts were perfused with varying concentrations of centrifuged and filtered human amniotic fluid. The most consistent change seen was a dose-dependent decrease in coronary flow rate. With 10% concentrations, a wide spectrum of changes was seen in both a positive and a negative direction for left ventricular pressure and change in pressure with respect to time, which were closely correlated with the degree of decrease in coronary flow rate. If amniotic fluid has a direct role in depressing cardiac function in amniotic fluid embolism, it may act by decreasing coronary flow rather than by directly suppressing myocardial activity.

Local versus general anesthesia for laparoscopic sterilization: a randomized study.

Despite the contention by some that local anesthesia is a preferred alternative to general anesthesia for laparoscopic sterilization, there have been no randomized studies comparing these techniques. To better characterize the relative safety and acceptability of these techniques for laparoscopic sterilization, we randomly assigned 100 women undergoing bipolar electrocoagulation or spring clip application to either local or general anesthesia. Of the 53 women assigned local anesthesia, four had their procedures completed using another technique because of technical problems related to obesity. Thirteen other obese women, however, underwent successful surgery with local anesthesia. Women undergoing local anesthesia had a slightly shorter anesthesia time (30 versus 36 minutes) and recovery room stay (65 versus 78 minutes). Women having general anesthesia were 2.3 and 1.5 times more likely to have maximum systolic and diastolic blood pressures above 160 and 90 mmHg, respectively. They were also 5.7 times more likely to have a maximum heart rate 110 or higher. Patient movement was reported to be a concern in five women undergoing general anesthesia, but in none having local anesthesia. An equal percentage (80%) of women in each group expressed satisfaction with their anesthetic technique.