Expanding access to coronary artery bypass surgery: who stands to gain?

OBJECTIVE--To determine the perceptions of general practitioners (GPs) about the benefits of coronary artery bypass surgery, in terms of gains in life expectancy, for different groups of patients. DESIGN--A questionnaire survey of all GPs in Northern Ireland. SETTING--A survey conducted collaboratively by the departments of public health medicine in each of the four health boards in the province, serving a total population of 1.5 million. MAIN OUTCOME MEASURES--The median and mean gain in life expectancy perceived by groups of doctors for smoking and non-smoking male and female 55 year old patients. The percentage of 50 year old and 70 year old non-smoking patients considered likely to have their lives extended with bypass surgery. Differences were assessed using the Mann-Whitney U test for unpaired samples and the Wilcoxon signed rank tests for paired. RESULTS--541 GPs replied (response rate 56%). The median (and mean) perceived gain in life expectancy after cardiac surgery for non-smoking 55 year old subjects was 120 (104) months for men and 120 (112) months for women (z = 6.42; P < 0.0001; Wilcoxon signed rank test). For male and female smokers of the same age, the perceived gains were 48 (47) and 60 (52) months respectively (z = 6.72; P < 0.0001; Wilcoxon signed ranks test), both figures being significantly different than for non-smokers. The median (and mean) percentage of patients that the doctors considered would have their lives extended by bypass surgery was 70 (64) of every 100 "young" patients and 40 (42) of every 100 "old" patients, (z = 16.2; P < 0.0001). CONCLUSIONS--These results point to a significant overestimation of the benefits of coronary artery bypass surgery by GPs in Northern Ireland and to a need to develop guidelines for referral.     

Teratogenic and embryocidal effects of Zidovudine (AZT) in sprague-dawley rats

Objective: The purpose of the present investigation was to analyze the effets of zidovudine on the postimplantation embryo and fetus.Methods: Pregnant Sprague-Dawley rats were given various doses (10 mg/kg, 30 mg/kg, 150 mg/kg) of zidovudine or saline by an endotracheal tube during the period of embryogenesis (days 6-8, 9-11, 6-11 postconception). The animals were sacrificed on days 18-19 of pregnancy, and their fetuses were removed by hysterotomy. Autopsies under low (15x) and high (40x) power light microscopy were performed on all fetuses.Results: There was no statistically significant difference among the groups with respect to maternal weight gain. There were more pregnancy resorptions in the group receiving high-dose zidovudine (150 mg/kg/day) throughout embryogenesis than in the control group (P = 0.001, respectively). Four major structural anomalies were noted among the 689 fetuses examined, but zidovudine was not associated with an increased frequency of congenital anomalies in rats when it was administered in doses similar to, 3-, and 15-fold higher than the regimen recommended for adult humans. The drug, however, was embryocidal in the high-dose group (P = 0.002).Conclusions: These findings are consistent with previous studies of preimplantation mouse embryos that demonstrated an embryocidal effect on preimplantation conceptuses. In summary, post-implantation embryonic zidovudine exposure was associated with significantly increased pregnancy losses (resorptions and intrauterine deaths).     

Outcomes of 17,137 pregnancies in 2 urban areas of Ukraine

OBJECTIVES: Frequent terminations of pregnancy and high rates of fetal loss have been reported, but not confirmed, in the former eastern bloc. A census of pregnancies in Ukraine, a former eastern bloc country, was conducted to determine the rates of these events. METHODS: All pregnancies registered in 2 urban areas were enumerated. During a 19-month period between 1992 and 1994, 17,137 pregnancies and their outcomes were recorded. RESULTS: Sixty percent of the pregnancies were voluntarily terminated, generally before the 13th week. In pregnancies delivered at 20+ weeks, fetal mortality was 29 per 1000, nearly 5 times the rate among Whites in the United States. There was a greater proportion of very early deliveries (20-27 weeks) in Ukraine, as well as higher death rates at all gestational ages. Perinatal mortality was estimated to be 35 per 1000, about 3 times the US rate. CONCLUSIONS: This is believed to be the first study in the former eastern bloc to ascertain all of the clinically recognized pregnancies in a specified period and to determine their outcomes. The data document elevated reproductive risks in a former Soviet state.     

Comparison of soft tissue profile changes in serial extraction and late premolar extraction

To assess soft tissue profile changes through time, a comparison was made of patients treated by serial extraction without subsequent orthodontic treatment (n=28), patients treated with serial extraction and orthodontic treatment (n=30), and patients treated orthodontically with late extraction (n=30). Cephalometric radiographs were traced and digitized; linear and angular measurements were made with a custom computer program that allowed digitization of specific soft tissue points. Maxillary, mandibular, and overall cephalometric superimpositions and linear measurements of change from the superimpositions were done by hand. Statistical analyses were made to determine if significant differences existed within each group at each time period and between groups at each time period, as well as between males and females at each time period. Data were also analyzed to determine if significant correlations existed between any hard tissue variable and any soft tissue variable, or between any soft tissue variable and any other soft tissue variable. It was found that in those patients treated with late premolar extraction, the most labial point of the mandibular incisor was more posterior from pretreatment to posttreatment than in the serial extraction group. While a great number of associations existed between variables, no significant differences were found between the soft tissue profiles of these three groups of patients. The gender differences that were found to exist were most likely due to normal maturational changes, not the treatment itself.     

Risk factors for assaults on nursing staff: childhood abuse and education level

OBJECTIVES: This study examined risk factors for nursing staff associated with being assaulted in the workplace and described the prevalence of staff assaults on patients. BACKGROUND: Most studies examining assaults in the workplace examine patient variables. Scant empirical investigation has occurred of staff variables. METHODS: A random mailed survey measuring physical and psychological assaults, sexual assault, and trauma history was employed. Childhood abuse and education were unique predictors of physical and sexual assault by patients. The results also revealed that staff members sometimes abuse patients. IMPLICATIONS: These results can help inform the training and supervision of nursing staff. Strategies to decrease staff vulnerability of being assaulted may reduce the risk. The finding that education also may be a protective factor has important implications for trends in managed care to downsize nursing. Protecting patients and staff are important administrative priorities in the workplace.     

Modification of the cardiovascular response to hemorrhage by somatic afferent nerve stimulation with special reference to gut and skeletal muscle blood flow.

BACKGROUND: Tissue injury modifies heart rate and blood pressure responses to hemorrhage. The effect of concomitant injury on the hemorrhage-induced redistribution of cardiac output is much less clear. However, if injury elicits the visceral alerting response of the defense reaction, then a change in this redistribution of peripheral blood flow might be expected. If such a change compromised the gut circulation, then it might explain the deleterious effects of injury on the ability to withstand hemorrhage. METHODS: Immature pigs anesthetized with Saffan were bled 30% of blood volume with or without concomitant somatic afferent (brachial) nerve stimulation (to mimic injury). In addition to global cardiovascular and oxygen transport variables, blood flow was measured in the cranial mesenteric (gut) and right femoral (skeletal muscle) arteries after a 60-minute stabilization period after surgery, at the end of the 30-minute hemorrhage, and after a 30-minute shock period. RESULTS: Hemorrhage induced the expected cardiovascular and oxygen transport changes accompanied by a reduction in skeletal muscle blood flow and a 55% increase in skeletal muscle vascular resistance, but gut blood flow and vascular resistance were unchanged. However, in the presence of brachial nerve stimulation, the pattern of response to hemorrhage was modified, such that gut blood flow was now reduced and gut vascular resistance increased. CONCLUSION: The sparing of the gut circulation after hemorrhage was abolished in the presence of "injury." This finding is consistent with injury eliciting the defense reaction and may help explain the deleterious effects of injury on resistance to hypovolemia.     

Increased quantal release of acetylcholine at the neuromuscular junction following scald injury in the rat

Following severe burns, patients frequently develop a profound resistance to nondepolarizing neuromuscular blockers. Several mechanisms have been proposed to account for this, including upregulation of nicotinic acetylcholine receptors. We investigated the effects of a 30% body surface area (BSA) scald on neuromuscular transmission in slow-twitch soleus (SOL) and fast-twitch extensor digitorum longus (EDL) of rats. Rats were sacrificed 72 h after the injury, a time at which sepsis is unlikely and body weight gain and core temperature have returned to normal. Further groups of rats were sham operated and either pair fed to the scalded rats or freely fed to assess the influence of food restriction. When compared with muscle from pair-fed control rats, scald resulted in an almost 50% increase in miniature endplate potential (mEPP) frequency in both SOL and EDL. However, scald did not increase mean mEPP amplitude in SOL, although it did cause a 10% increase in EDL. Scald injury did produce a significant increase in the size of the evoked endplate potential in SOL (33%) and EDL (37%). These data indicate that a significant increase in the quantal content of evoked transmitter released in SOL (38%) and EDL (30%) occurred by 72 h after scald. Such an increase may contribute to the resistance to nondepolarizing neuromuscular blockers documented in patients following thermal injury.     

Abdominal wound problems after hysterectomy with electrocautery vs. scalpel subcutaneous incision

The purpose of this study was to evaluate the relationship between postoperative abdominal incision problems and opening subcutaneous tissues with electrocautery or scalpel. Women scheduled for elective abdominal hysterectomy who gave informed consent were randomly assigned to subcutaneous abdominal wall tissue incision by electrocautery or scalpel. Postoperative abdominal wound problem diagnoses included seroma, hematoma, infection, or dehiscence without identifiable etiology. Fifteen of 380 women (3.9%) developed a wound problem; six had scalpel and nine had electrosurgical subcutaneous incisions (P = 0.4). Thicker subcutaneous tissues (P = 0.04) and concurrent pelvic infection (P < 0.001) were significant risk factors for postoperative wound problems. Only two women (0.5%) developed an infection. We conclude that the method of subcutaneous tissue incision was unrelated to the development of postoperative abdominal incision problems in 380 women undergoing elective abdominal hysterectomy.     

A Field Test of the Sweat Patch

The sweat patch is a new, noninvasive method designed to estimate the ethanol consumption of drinking subjects. It consists of salt-impregnated absorbent pads protected by a plastic chamber with attached water-tight adhesive. The patch reportedly collects transepidermal fluid at a steady rate for up to 10 days. Recent laboratory research has indicated a linear relationship between the concentration of ethanol in transepidermal fluid and mean concentration of ethanol in blood. Levels of ethanol in the sweat patch allowed identification of persons drinking at least 0.5 g of ethanol/kg/day with 100% sensitivity and specificity. The study reported here was conducted to test the field effectiveness of this sweat patch in normal, active research subjects. First, several pretests were conducted to determine the optimal location of the patch on the body and its fluid uptake at various sites. A laboratory experiment using nonalcoholic subjects was conducted to replicate previous work, and methods of measuring ethanol concentration in the patch were refined. A field test of the patch was then carried out. Healthy active volunteers drank a single "moderate" dose of ethanol (0.5 g of ETOH/kg of body weight) and then remained abstinent for the next 3 days. A week later, a "heavy" dose (1.0/kg of body weight) was consumed. Only a trace of ethanol was detected in any of the patches worn in either experiment. The patch did not measure ethanol in the transepidermal fluid under field conditions. Thus, further design modifications and pilot testing are required before the full benefits of this unobtrusive measure of drinking can be realized.