Charles Hoff

Pneumonia as a Complication of Pregnancy

Objective: To identify risk factors for the development of antepartum pneumonia and to describe maternal and perinatal outcome in pregnant women with pneumonia.Methods: The study group consisted of 59 women with antepartum pneumonia. Pneumonia was defined by the presence of lower respiratory tract symptoms, radiographic findings, no other source of infection, and at least two of the following: oral temperature ≥38°C, white blood cell count ≥15,000/ml, auscultatory findings, and/or positive sputum cultures. For comparison, a control group (n = 118) of pregnant women was formed by selecting the first mother who delivered immediately before and after an index study subject.Results: Mothers in the study group were significantly more likely than women in the control group to have either a history of asthma (P = 0.022) or an admission hematocrit ≥30% (P < 0.001). Women with pneumonia were also more likely to receive a tocolytic agent (P < 0.001) and/or beta-methasone to enhance fetal lung maturity (P < 0.001). ...

Elevated plasma endothelin-1 levels in sickle cell anemia: Relationships to oxygen saturation and left ventricular hypertrophy

Endothelin‐1 (Et‐1) is a vasoconstrictor produced by endothelial and vascular smooth muscle cells in response to hypoxia, which induces hypertrophy in cultured cardiac myocytes. We measured plasma Et‐1 levels and left ventricular dimensions in 13 patients with sickle cell anemia (SCD) and in 12 African‐American controls ages 16–29 years. Endothelin‐1 concentrations are significantly higher in SCD subjects than controls (10.6 + 1.9 vs. 3.0 + 1.3 pmol/L). There was a negative correlation between oxygen saturation and Et‐1 levels in SCD patients (r = ‐0.71, P = 0.01). SCD subjects have more dilated and hypertrophied hearts corrected for body surface area than controls as evidenced by significant increases in left ventricular end diastolic dimension (31 + 0.8 vs. 24 + 0.9 mm/m2, P < 0.001), left ventricular end systolic dimension (20 + 0.9 vs. 16 &plus 0.8 mm/m2, P = 0.002), left ventricular posterior wall thickness (5.0 &plus 0.1 vs. 4.0 &plus 0.1 mm/m2, P < 0.001), and left ventricular mass (125 + 7.2 vs. 69 + 5.1 g/m2, P < 0.001). The index of left ventricular function, the shortening fraction, was not different between groups (34 + 1.2% in SCD vs. 35 + 1.5% in controls). The correlation between left ventricular mass and levels of Et‐1 in SCD subjects was not significant (r = 0.47, P = 0.121). Am. J. Hematol. 58:195–199, 1998.

High vagal tone is associated with more efficient regulation of homeostasis in low‐risk human fetuses

Homeostasis is maintained primarily by the parasympathetic nervous system and is thought to provide a physiological substrate for the development of complex behaviors. This investigation was undertaken to test the hypothesis that infants with high parasympathetic tone are more efficient regulators of homeostasis than infants with low parasympathetic tone. Respiratory sinus arrhythmia (RSA) was used as a measure of parasympathetic tone, and the efficiency of homeostatic control was quantified, for each infant, by the slope (SRSA) and correlation coefficient (RRSA) of the regression line relating fluctuations in heart period and fluctuations in RSA. To test our hypothesis, we examined the relationship between RSA and both SRSA and RRSA in 34 low-risk human fetuses between 36 and 40 weeks gestation. We found that fetuses who were parasympathetic-dominated had larger SRSA and RRSA values, and hence were more efficient regulators of homeostasis, than fetuses who were sympathetic-dominated. The results of our analyses are important because they establish, very early in development, a physiological basis for the relationship between vagal tone and the development of complex behaviors.

In vitro lymphocyte activity in women with endometriosis—an altered immune response? * †

OBJECTIVE To determine the possible role of the immune system in the pathogenesis of endometriosis. DESIGN The lymphocyte proliferative response in the presence of autologous endometrial cells was assayed by tritiated thymidine incorporation. SETTING Patients were recruited from a university outpatient clinic. MAIN OUTCOME MEASURE To determine the lymphocyte proliferative response to endometrium in controls and patients with endometriosis. PARTICIPANTS Twenty patients with endometriosis and 26 control women were studied. RESULTS The lymphocyte proliferative response in the presence of autologous endometrium was significantly lower in women with endometriosis when compared with controls. CONCLUSION This study indicates that an altered lymphocyte/endometrial cell relationship is operational in women with endometriosis and may contribute to the pathogenesis of the disease.

Trend associations of smoking with maternal, fetal, and neonatal morbidity.

&NA; Smoking habits, prenatal health, and pregnancy outcome were surveyed among 1700 nulliparous women. During pregnancy, increases in levels of hemoglobin and hematocrit and the frequency of women reporting bleeding and decreases in diastolic pressure and frequency of toxemia were observed with increased maternal smoking. A higher frequency of fetal bradycardia was detected among women smoking greater than or equal to one‐half pack per day. With increased smoking there was an increased frequency of abnormal placentas. Mean birth weight and crown‐heel length decreased with increased smoking, and neonates born to women smoking greater than or equal to one‐half pack per day had a higher frequency of jaundice. The association between smoking and reduced birth weight and crown‐heel length persisted after controlling for gestational age, maternal weight gain, prenatal visits, and other confounding variables. (Obstet Gynecol 68:317, 1986)

Blood Pressure Changes in Normotensive Women Readmitted in the Postpartum Period with Severe Preeclampsia/Eclampsia

The purpose of this study was to determine whether women who had no clinical evidence of preeclampsia at delivery, but who were later readmitted with postpartum severe preeclampsia or eclampsia, differed in mean arterial pressure (MAP) and clinical presentation from women who either remained normotensive or had severe preeclampsia or eclampsia at the time of delivery. Control subjects did not require readmission and were matched (2:1) with study subjects in consecutive order for date of delivery and maternal age, race, and parity. Women in the study group had a significantly greater increase in MAP after delivery than control subjects, and analysis of variance for linear trends demonstrated highly significant differences between the study and control groups in the average intrapartum and postpartum MAPs. Compared to women in either control group, mothers who were readmitted were significantly more likely to demonstrate a > 10-mm Hg increase in MAP between the intrapartum and postpartum periods (delta MAP). Normotensive women with a delta MAP > 10 mm Hg had more than a threefold risk of readmission in the postpartum period with severe preeclampsia or eclampsia. Women who were readmitted reported a significantly greater frequency of headaches and nausea and vomiting than women with intrapartum preeclampsia. In summary, our findings indicate that MAP increase following delivery in normotensive women who were later readmitted with severe preeclampsia or eclampsia.

Protection Afforded by Sickle-Cell Trait (Hb AS): What Happens when Malarial Selection Pressures Are Alleviated?

A study of reproductive outcome in Mobile, AL was conducted among a large maternal cohort with sickle-cell disease (Hb SS), sickle-cell trait (Hb AS), and no hemoglobinopathies (Hb AA). It was found that mean gravidity and live births among Hb AS women were significantly higher than among Hb AA women. These findings were surprising since it is generally held that once malarial pressure is alleviated, any reproductive advantage that might be conferred by Hb AS would disappear and fertility levels would reach levels similar to or slightly less than that of Hb AA women. A search of the literature was subsequently conducted and a large cohort study of an African-derived population was found in the United Kingdom. Results from this study also showed that parity was significantly higher among Hb AS women compared to Hb AA women. If survivorship is similar among Hb AS and Hb SS women, findings from these two studies raise doubts whether directional selection is occurring against the Hb S allele in nonmalarial environments. Balancing selection may still be occurring.

Association Between Maternal‐Fetal HLA‐DR Relationships and Fetal Growth

PROBLEM: To determine whether maternal‐fetal human leukocyte antigen (HLA) antigenic relationships are associated with differential fetal growth in weight.

Hepatic function as assessed by lidocaine metabolism in sickle cell disease

OBJECTIVE To evaluate hepatic drug metabolism, as determined by the formation of monoethylglycinexylidide (MEGX) after lidocaine injection and indocyanine green (ICG) clearance, in patients with sickle cell disease. STUDY DESIGN A case-control study including 19 patients with homozygous hemoglobin S, and 13 age- and sex-matched black control subjects. Serum MEGX concentration was measured after intravenous injection of 1 mg/kg (maximum 50 mg) lidocaine. ICG (0.5 mg/kg) was injected concomitantly and absorbance (805 nm) of serum was measured over time to determine its volume of distribution, serum half-life, and hepatic blood flow. RESULTS MEGX formation at 15 minutes was decreased in patients with sickle cell disease compared with formation in the control subjects (39.9 +/- 18.0 vs 65.6 +/- 50.0 micrograms/L, respectively, p < 0.02). The volume of distribution of ICG was increased in patients with sickle cell disease compared with that in the control subjects (0.21 +/- 0.09 vs 0.11 +/- 0.03 L/kg, p < 0.01). This partly accounts for the decreased MEGX formation. The ICG half-life was similar in both groups (3.8 +/- 1.5 vs 3.1 +/- 1.0 min). Hepatic blood flow, derived from ICG clearance, was increased in sickle cell patients compared with that of the control subjects (12.2 +/- 4.5 vs 8.1 +/- 2.1 ml/kg/min, p < 0.01). CONCLUSION Hepatic drug metabolism, as assessed by MEGX formation after lidocaine injection, is impaired in patients with sickle cell disease. This impairment may have clinical implications when using hepatically metabolized medications in patients with sickle cell disease.

Methods used to diagnose premature rupture of membranes: a national survey of 812 obstetric nurses

Objective To identify methods used to diagnose premature rupture of membranes (PROM). Methods A 14-item questionnaire was mailed to 1992 registered nurses certified in inpatient obstetrics to determine information on practice facility, obstetric services, procedures used to obtain vaginal fluids for testing, and methods used to diagnose PROM. Results A total of 812 (40.8%) surveys were available for analysis. Of tests used to confirm PROM, observation of pooling fluid in the posterior fornix and fern tests were much more likely to be used in teaching and military hospitals and in facilities with tertiary obstetric services than in private hospitals (all P values < .001). To obtain vaginal fluids for fern and nitrazine testing, the dry glove method (ie, insertion of a gloved hand or nitrazine strip into the vagina) was used significantly more often in private hospitals than in teaching or military facilities (P < .001). In addition, the dry glove method was used significantly more often (P < .001) and the speculum examination was used less often (P < .001) to collect vaginal fluids for testing when private physicians performed more than 75% of deliveries at a particular hospital. In contrast, vaginal fluid was obtained during a sterile speculum examination more often in facilities in which more than 75% of deliveries were performed by residents (P < .001), and/or when more than 75% of speculum examinations were performed by nursing personnel (P < .001). Multiple linear regression analyses indicated that observation of pooling fluid and use of the fern test were significantly associated with hospital type, percentage of deliveries by private physicians, and percentage of speculum examinations performed by nursing personnel (all P values < .001). Conclusion A sterile speculum examination is used more often to obtain vaginal fluids for testing and to diagnose ruptured membranes in teaching or military facilities and when nursing personnel have been trained in speculum examinations.