Does deprivation index modify the acute effect of black smoke on cardiorespiratory mortality?

OBJECTIVES: To investigate whether deprivation index modifies the acute effect of black smoke on cardiorespiratory mortality. METHODS: Generalised linear Poisson regression models were used to investigate whether deprivation index (as measured by the Carstairs deprivation index) modified the acute effect of black smoke on mortality in two largest Scottish cities (Glasgow and Edinburgh) between January 1981 and December 2001. Lag periods of up to 1 month were assumed for the effects of black smoke. RESULTS: Deprivation index significantly modified the effect of black smoke on mortality, with black smoke effects generally increasing as level of deprivation increased. The interaction coefficient from a parametric model assuming a linear interaction between black smoke (microg/m(-3)) and deprivation in their effect on mortality--equivalent to a test of 'linear trend' across Carstairs categories--was significant for all mortality outcomes. In a model where black smoke effects were estimated independently for each deprivation category, the estimated increase in respiratory mortality over the ensuing 1-month period associated with a 10 microg/m(3) increase in the mean black smoke concentration was 8.0% (95% CI 5.1 to 10.9) for subjects residing in the 'most' deprived category (Carstairs category 7) compared to 3.7% (95% CI -0.7 to 8.4) for subjects residing in the 'least' deprived category (Carstairs category 1). CONCLUSIONS: The results suggest a stronger effect of black smoke on mortality among people living in more deprived areas. The effect was greatest for respiratory mortality, although significant trends were also seen for other groups. If corroborated, these findings could have important public health implications.

Interacting effects of particulate pollution and cold temperature on cardiorespiratory mortality in Scotland.

OBJECTIVES: To determine whether the effect of black smoke on cardiorespiratory mortality is modified by cold temperatures. METHODS: Poisson regression models were used to investigate the relationship between lagged black smoke concentration and daily mortality, and whether the effect of black smoke on mortality was modified by cold temperature for three Scottish cities from January 1981 to December 2001. MAIN RESULTS: For all-cause respiratory and non-cardiorespiratory mortality, there was a significant association between mortality and lagged black smoke concentration. Generally the maximum black smoke effect occurred at lag 0, although these estimates were not statistically significant. A 10 mugm(-3) increase in the daily mean black smoke concentration on any given day was associated with a 1.68% (95% CI 0.72 to 2.65) increase in all-cause mortality and a 0.43% (95% CI -0.97 to 1.86), 5.36% (95% CI 2.93 to 7.84) and 2.13% (95% CI 0.82 to 3.47) increase in cardiovascular, respiratory and non-cardiorespiratory mortality, respectively, over the ensuing 30-day period. The effect of black smoke on mortality did not vary significantly between seasons (cool and warm periods). For all-cause, cardiovascular and non-cardiorespiratory mortality the inclusion of interaction terms did not improve the models, although for all-cause and non-cardiorespiratory mortality there was a suggestion for interaction between temperature and recent black smoke exposure. CONCLUSIONS: The results of this study suggested a greater effect of black smoke on mortality at low temperatures. Since extremes of cold and particulate pollution may coexist, for example during temperature inversion, these results may have important public health implications.

The lagged effect of cold temperature and wind chill on cardiorespiratory mortality in Scotland.

AIMS: To investigate the lagged effects of cold temperature on cardiorespiratory mortality and to determine whether "wind chill" is a better predictor of these effects than "dry bulb" temperature. METHODS: Generalised linear Poisson regression models were used to investigate the relation between mortality and "dry bulb" and "wind chill" temperatures in the three largest Scottish cities (Glasgow, Edinburgh, and Aberdeen) between January 1981 and December 2001. Effects of temperature on mortality (lags up to one month) were quantified. Analyses were conducted for the whole year and by season (cool and warm seasons). MAIN RESULTS: Temperature was a significant predictor of mortality with the strongest association observed between temperature and respiratory mortality. There was a non-linear association between mortality and temperature. Mortality increased as temperatures fell throughout the range, but the rate of increase was steeper at temperatures below 11 degrees C. The association between temperature and mortality persisted at lag periods beyond two weeks but the effect size generally decreased with increasing lag. For temperatures below 11 degrees C, a 1 degrees C drop in the daytime mean temperature on any one day was associated with an increase in mortality of 2.9% (95% CI 2.5 to 3.4), 3.4% (95% CI 2.6 to 4.1), 4.8% (95% CI 3.5 to 6.2) and 1.7% (95% CI 1.0 to 2.4) over the following month for all cause, cardiovascular, respiratory, and "other" cause mortality respectively. The effect of temperature on mortality was not observed to be significantly modified by season. There was little indication that "wind chill" temperature was a better predictor of mortality than "dry bulb" temperature. CONCLUSIONS: Exposure to cold temperature is an important public health problem in Scotland, particularly for those dying from respiratory disease.

Heparin-induced cutaneous necrosis in a postpartum patient.

A case of heparin-induced cutaneous necrosis resembling necrotizing fasciitis occurred in a post-cesarean section patient. She presented with massive necrosis of the skin and abdominal pannus on the sixth postoperative day after a cesarean section for severe preeclampsia and failed induction. A biopsy showed findings characteristic of heparin-induced cutaneous necrosis, permitting conservative therapy.

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

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

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

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

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

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

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.

Decreased tear osmolarity and absence of the inferior marginal tear strip after sleep.

To better understand some of the clinical syndromes that patients experience on eyelid opening in the morning, we examined four patients clinically and measured tear osmolarity immediately after sleep and later in the day. The inferior marginal tear strip was absent, and tear osmolarity was at its nadir on eyelid opening after sleep. We propose a mechanism whereby decreased osmolarity, together with a probable decrease in tear volume, may increase lid-corneal and soft contact lens-corneal adhesion during sleep, and help explain both the development of recurrent corneal erosions on awakening and the tendency of soft contact lenses to adhere to the cornea overnight.

ST segment depression in paired electrocardiograms and serum electrolytes in pregnant women receiving intravenous ritodrine.

Forty-three women admitted for preterm labor had electrocardiograms and serum potassium and glucose levels determined before and two and four hours after the initiation of intravenous ritodrine tocolysis. The ST segment depression found at two and four hours was significant but not dependent upon a fall in potassium or increase in the heart rate or glucose level. Such symptoms as chest pain and dyspnea were also not dependent upon potassium, glucose or heart rate changes. These findings support the concept of an intrinsic drug effect.

Uterine hyperstimulation resulting from intravaginal prostaglandin E2. A case report.

Prostaglandin E2 administered intravaginally is an effective method of improving Bishop scores in patients requiring elective induction of labor. We treated a woman for hypertonic uterine contractions that occurred over a five-hour period after application of 5 mg of prostaglandin E2. Sedation and magnesium sulfate were not effective in decreasing the intensity of the contractions, but terbutaline, 0.25 mg subcutaneously, was.

Percutaneous balloon mitral valvuloplasty in a pregnant woman with mitral stenosis, sickle cell crisis and acute pulmonary edema. A case report.

A woman with acute congestive heart failure secondary to mitral stenosis and sickle cell crisis was treated successfully with a combination of an exchange transfusion and percutaneous balloon valvuloplasty. That combination provided an alternative to surgical mitral commissurotomy, with its significant risks for both the mother and fetus. The patient was able to undergo an uncomplicated pregnancy course despite the increased risk of cardiac decompensation in the intrapartum and postpartum period.

Iatrogenic omental percutaneous shunt and resolution of obstructive fetal uropathy. A case report.

A double pigtail stent was placed to decompress an obstructed fetal kidney. The stent was dislodged, causing an iatrogenic marsupialization between the renal pelvis omentum and skin. The omentum acted as a drain, decompressing the kidney.

Associations between short/medium-term variations in black smoke air pollution and mortality in the Glasgow conurbation, UK.

OBJECTIVES: To examine associations between short/medium-term variations in black smoke air pollution and mortality in the population of Glasgow and the adjacent towns of Renfrew and Paisley over a 25-year period at different time lags (0-30 days). METHODS: Generalised linear (Poisson) models were used to investigate the relationship between lagged black smoke concentrations and daily mortality, with allowance for confounding by cold temperature, between 1974 and 1998. RESULTS: When a range of lag periods were investigated significant associations were noted between temperature-adjusted black smoke exposure and all-cause mortality at lag periods of 13-18 and 19-24 days, and respiratory mortality at lag periods of 1-6, 7-12, and 13-18 days. Significant associations between cardiovascular mortality and temperature-adjusted black smoke were not observed. After adjusting for the effects of temperature a 10 µgm(-3) increase in black smoke concentration on a given day was associated with a 0.9% [95% Confidence Interval (CI): 0.3-1.5%] increase in all cause mortality and a 3.1% [95% CI: 1.4-4.9%] increase in respiratory mortality over the ensuing 30-day period. In contrast for a 10 µgm(-3) increase in black smoke concentration over 0-3 day lag period, the temperature adjusted exposure mortality associations were substantially lower (0.2% [95% CI: -0.0-0.4%] and 0.3% [95% CI: -0.2-0.8%] increases for all-cause and respiratory mortality respectively). CONCLUSIONS: This study has provided evidence of association between black smoke exposure and mortality at longer lag periods than have been investigated in the majority of time series analyses.

Work-related eye injuries.

Twenty-one patients admitted between 1977 and 1982 to the Medical College of Virginia were studied retrospectively for work-related eye injuries. This group comprised 7.7% of all eye-injury admissions. Patients suffered both blunt and penetrating injuries; penetrating injuries had poorer prognoses. Twenty of the 21 patients had not worn protective eyewear. The average per-patient cost related to ocular injury was $2946, and the average hospital stay was 6.4 days. In contrast, the one patient who had worn protective eyewear had ocular-related costs and hospitalization of only $350 and a one-day stay. Protective eyewear is important in lessening the severity of injury as well as decreasing the financial and psychologic burden to the patient, hospital, and employer.

Mid-P confidence intervals for the Poisson expectation.

Conventionally a confidence interval (CI) for the standardized mortality ratio is set using the conservative CI for a Poisson expectation, mu. Employing the mid-P argument we present alternative CIs that are shorter than the conventional ones. The mid-P intervals do not guarantee the nominal confidence level, but the true coverage probability is only lower than the nominal level for a few short ranges of mu. The implications for mid-P confidence intervals of various proposed definitions of two-sided tests for discrete data are discussed.

The sequential use of estradiol and prostaglandin E2 topical gels for cervical ripening in high-risk term pregnancies requiring induction of labor.

We compared the safety and efficiency of 200 mg of estradiol valerate prepared as a topical cervical gel as a preripening agent when used 6 hours before the application of 2 mg of prostaglandin E2 gel for the purpose of cervical ripening in 40 high-risk obstetric patients before indicated oxytocin induction of labor. When compared with a placebo prostaglandin E2 dosage, the estradiol had no effect on the change of Bishop score, length of labor, amount of oxytocin required, or the cesarean delivery rate. While no uterine contractions were noted after the application of the estradiol, 85% of patients had recordable uterine activity after the application of prostaglandin E2, suggesting that even at the 2 mg dosage this sequential regimen is not appropriate for local cervical ripening.

Heat production during sleep.

Heat production during sleep was studied by continuous indirect calorimetry with simultaneous electroencephalographic monitoring. Controlling for gross influences on heat production, comparisons of heat production during different sleep stages showed heat production in stage 4 sleep to be significantly lower than in other sleep stages. There appeared to be a gradation in heat production in non-rapid-eye-movement stages of sleep with stage 2 higher and stage 4 lower than stage 3. Heat production in stage 4 was less variable than in any other sleep stage. Both the level and variability of heat production was similar in stage 2 and rapid-eye-movement sleep. Heat production during the night was 9% lower than during resting wakefulness. The average heat production in stage 4 sleep was 14.4% lower than resting wakeful values.

Clinical significance of transient visual phenomena in the elderly.

To evaluate the significance of transient visual phenomena in the elderly patient, a retrospective study of 43 patients over 40 years of age (mean, 58) presenting between 1971 and 1982 was conducted. Historical, clinical and diagnostic features were collated and analyzed by computer. The study revealed that 31 patients were diagnosed as migraine and 12 as vertebrobasilar insufficiency based on features identified in this review. Follow-up was obtained in 90% of the patients with a mean follow-up of 2.4 years. In general, prognosis proved to be excellent, with two deaths of cardiac origin and an 81% incidence of remission or symptomatic improvement of the visual events. No retinal or cerebral strokes were observed and TIAs occurred in only 9% of the population. This study suggests that transient visual phenomena in the elderly are benign.