Atrial fibrillation after coronary artery bypass grafting without cardiopulmonary bypass

OBJECTIVE

Atrial fibrillation is the most common complication after heart surgery. It rarely has a fatal outcome but causes patient instability, prolongs hospital stay, or even is the reason for perioperative infarction. Although conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass has excellent short-term and long-term results, the number of coronary operations on a beating heart without cardiopulmonary bypass is still growing. To reduce surgical trauma, off-pump coronary artery bypass grafting via sternotomy (OPCABG) or minimally invasive direct vision coronary artery bypass grafting (MIDCABG) via small thoracotomy are performed. The aim of this study was to estimate the frequency of atrial fibrillation in patients after myocardial revascularization without cardiopulmonary bypass.

METHODS

A retrospective analysis of 48 patients undergoing myocardial revascularization without cardiopulmonary bypass was performed. Twenty-four patients underwent OPCABG and 24 were operated using the MIDCABG technique. The incidence of cardiac arrhythmias was analyzed since operation to the fourth postoperative day. Each patient had continuous ECG monitoring with option of arrhythmia analysis during ICU stay. After discharge from ICU 24-h ECG monitor studies were carried out. Surface 12-lead ECG was accomplished once a day, and additionally each time symptoms of cardiac arrhythmia occurred. Risk factors of atrial fibrillation were estimated.

RESULTS

Atrial fibrillation occurred in 25% of patients after MIDCABG, in 29% after OPCABG, and in 18% after CABG with cardiopulmonary bypass. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups.

CONCLUSIONS

Atrial fibrillation is a common complication after procedures of myocardial revascularization, performed with or without cardiopulmonary bypass. The occurrence is not dependent on the type of operation.

Thermographic assessment of stellate ganglion block effectiveness during cardiosurgical procedures

The study present thermographic assessment of the effectiveness of temporary stellate blockade performed during cardiosurgical procedures. The assumption behind this method was the increase in the temperature of upper extremity on the side of blockade, due to the broadening of arterial bed.

MATERIAL AND METHOD

The study was conducted on a group of 30 patients (21 men and 9 women) operated due to coronary disease involving three vessels. Mean age of the patients was 53 years. After introduction of anaesthesia blockade were performed with 2 ml 2% lignocainum and 8 ml 0.5% bupivacaine solution using peratracheal approach. Blockade effectiveness was assessed on the basis of images obtained in thermovisual camera, comparing the temperatures of upper extremity before and within 15 minutes after performing the blockade. Free blood outflow from radial artery, its diameter and length were also evaluated. The results obtained were subject to statistical analysis.

RESULTS

Twenty-three patients (76.6%) displayed the increase in the temperature of upper extremity by 1-3 degrees C. Free blood outflow from radial artery was greater in this group than in the remaining patients.

CONCLUSIONS

Thermography is a useful method for the assessment of stellate blockade effectiveness. Effective blockade results in the increased blood flow in radial artery.

[Less invasive coronary artery bypass grafting]

Myocardial revascularization had its beginnings in the early 1900s with extracardiac operations, such as sympathetic denervation and thyroid ablation. Since than it evolved to saphenous vein- and mammary artery-coronary artery bypass grafting (CABG) on the beating heart in the 1960s and after 1975 with the use of cardiopulmonary bypass (CPB) and cardioplegic arrest. Although excellent short-term and long-term results have been obtained with conventional CABG on cardiopulmonary bypass, there is still significant mortality and morbidity associated with the procedure, especially in the higher risk patients. To reduce surgical trauma off-pump coronary artery bypass grafting (OPCABG) and minimally invasive direct vision coronary artery bypass grafting (MIDCABG) are performed. Totally endoscopic operations are still in experimental stage. In the article optional less invasive surgical techniques are described.

Insurance coverage for prescription drugs: effects on use and expenditures in the Medicare population

BACKGROUND

Although most of the elderly are covered by Medicare, they potentially face large out-of-pocket costs for their health care because of excluded services. Aside from nursing home care, the exclusion of prescription drugs is one of the most significant. Several earlier policy initiatives have proposed adding prescription drug coverage to the Medicare program. To determine the effects of such an expansion, one must account for the potential increase in the demand for prescription drugs from providing insurance coverage.

METHODS

The study uses a new data source, the RAND Elderly Health Supplement to the 1990 Panel Study of Income Dynamics (PSID). The endogenity of insurance coverage is tested using instruments that exploit the longitudinal nature of the data. Equations are estimated on 910 persons (> or = 66 years) using a two-part model.

RESULTS

Insurance coverage for prescription drugs significantly increases the probability of use, but not of total expenditures, among those who use prescription drugs. However, insurance coverage significantly lowers out-of-pocket expenditures, thereby decreasing the financial burden on elderly households associated with prescription drug use. Medicaid coverage has effects that are smaller than those for private insurance, but the magnitude is less precisely estimated. These findings imply that if prescription drug coverage were added to Medicare, expected expenditures on drugs would rise by on average $83 for each elderly Medicare beneficiary (in 1990 dollars), although this increase is significant only at the 90% level. If the benefit had been included under Medicare, expected spending on prescription drugs by the elderly would have risen by approximately 20%, or $2.6 billion in 1990.

Stroke volume variability--cardiovascular response to orthostatic maneuver in patients with coronary artery diseases

The dynamics of cardiovascular responses to postural stress have not been fully recognized. To determine whether coronary artery bypass grafting (CABG) has any effect on stroke volume variability (SVV), the power spectrum components of SVV were measured in 60 patients before and at 6 weeks after CABG. Stroke volume was assessed by means of the thoracic bioimpedance method. The thoracic impedance cardiogram and ECG were recorded in the supine and standing positions with controlled breathing rate (0.25 Hz) during 10-minute periods. The analysis of SVV was done by means of the autoregressive method. The total power, the power in the low-frequency band LFSV (0.05-0.15 Hz), the power in the high-frequency band HFSV (0.15-0.5 Hz), and the LFSV/HFSV ratio were analyzed. Before CABG, we did not notice any significant changes in the stroke volume spectral power indices. After CABG, all spectral indices were significantly decreased in the standing position.

Measuring the cost of neonatal and perinatal care

This article provides an overview of neonatal intensive care unit (NICU) treatment costs. It discusses data sources as well as the methods for measuring costs, contrasting the strengths and weaknesses of alternate approaches. In addition, detailed information on NICU treatment costs is presented from a nationally representative sample of 25 hospitals with NICUs. The sample consists of 3288 very low birth weight infants (</=1500 g at birth) with admission dates between January 1, 1993, and September 30, 1994. Information on median treatment cost per infant, ancillary costs, accommodation costs, length of stay, and cost per day are presented. In addition, ancillary costs are disaggregated further into those for respiratory therapy, laboratory, radiology, pharmacy, and all other ancillary services.

Cost-effectiveness of care for very low birth weight infants

OBJECTIVE

Very low birth weight (VLBW)infants (those with birth weights <1500 g) account for only 1.2% of births but 46% of infant deaths. Large improvements in neonatal technology in the last 2 decades have significantly improved survival prospects for infants with low birth weights, but at a high cost. Due largely to a lack of data, the costs of medical care during the period in which infant mortality is measured (the first year of life), as well as the cost-effectiveness of that care for VLBW infants, have not been quantified. Despite this fact, public policies both toward providing insurance coverage for their care, as well as denying payment for their treatment, have either been proposed or implemented on cost-effectiveness grounds.

PATIENTS

The study includes all VLBW single live births in the state of California during 1986 and 1987 that were continuously eligible (through traditional channels) for the state's Medicaid program.

MAIN OUTCOME MEASURES

Treatment costs were measured for all medical care received during the first year of life, including all inpatient and outpatient care received. The cost-effectiveness of care is measured by aggregate treatment costs for all singleton VLBW liveborns divided by the number of first-year survivors.

RESULTS

Average treatment costs per first-year survivor for infants <1500 g was $93 800 (in 1987 constant dollars). Treatment costs per survivor were twice as high for infants <750 g ($273 900) as for the next highest birth weight group 750 to 999 g ($138 800) which was itself almost twice as high as for the 1000 to 1249 g group ($75 100). The gradient in cost-effectiveness with birth weight then drops off to $58 000 per survivor for infants with birth weights between 1250 and 1499 g.

CONCLUSION

Public policies aimed at improving birth outcomes by providing insurance coverage for pregnant women and children, such as the recent Medicaid expansions, can potentially be very cost-effective. Although maternal interventions such as prenatal care are relatively inexpensive, each normal birth that results instead in a VLBW birth saves $59 700 in first year medical expenses. However, cost savings attributable to increased birth weights depend on where in the birth weight distribution the increase occurs as well as the size of the birth weight increase. For infants with birth weights >750 g, significant gains can accrue from even a small shift in the birth weight distribution. A shift of 250 g at birth saves an average of $12 000 to $16 000 in first year medical costs and a shift of 500 g generates $28 000 in savings. However, there is a threshold effect on birth weight. For infants <750 g, increases in birth weight may increase medical expenditures. For instance, a shift in birth weight to the 750 to 999 g range increases costs by $29 000.

The financial burden of prescription drug use among elderly persons

Expenditures for prescription drugs are not covered by Medicare and are thus a potential source of large out-of-pocket expenditures for elderly persons. This study, using a new data source, the 1990 Elderly Health Supplement to the Panel Study of Income Dynamics (PSID), demonstrates that, among elderly persons, insurance coverage for drugs reduces the fraction of household income spent on prescription drugs by 50 percent. Groups most likely to benefit from insurance coverage are elderly women and those with common chronic conditions, low incomes, and rural residences.

Long-term determinants of patterns of health insurance coverage in the Medicare population

Using data from the 1990 Health Supplement to the Panel Study of Income Dynamics, we examine the determinants of patterns of insurance coverage among the elderly. Among those with supplemental insurance through an employment-based source, the primary determinant of having insurance is work history, specifically job tenure and occupation of household heads and their spouses. Among those who do not have employer-provided insurance, wealth is the most important economic factor in the purchase of private insurance. Blacks, persons with less education and women household heads are less likely to purchase supplemental insurance. We find little evidence that persons in prior poor health are more likely to purchase supplemental insurance, and the most important determinant of dental or drug coverage is having employer-based insurance. The current trend toward decreased generosity of post-retirement benefits implies that fewer older Americans will have insurance for these services.

Hospital and patient characteristics associated with variation in 28-day mortality rates for very low birth weight infants. Vermont Oxford Network

BACKGROUND

The outcomes for very low birth weight infants vary among neonatal intensive care units (NICUs), but the reasons for this variation are not well understood. We used the database of a large neonatology research network to determine whether either admission characteristics of the infants or specific characteristics of the units such as annual patient volume and the presence of a pediatric residency program could account for observed differences in neonatal mortality rates among units.

METHODS

We studied 7672 infants with birth weights from 501 to 1500 g treated during 1991 and 1992 at 62 NICUs participating in the Vermont Oxford Network Database.

RESULTS

Overall, 14.7% of the study infants died within 28 days of birth (interquartile range 9.9% to 18.1%). The ratio of the number of observed deaths at an NICU to the number of deaths predicted based on the characteristics of infants treated at the NICU (standardized neonatal mortality ratio, [SNMR]) varied significantly among units (range 0 to 1.69, z = 4.24). There was no association between annual patient volume and either mortality rate (r = .17) or SNMR (r = .22). Observed mortality rates (17% vs 13%) and SNMR (1.04 vs .87) were both higher at the 24 hospitals with pediatric residency training programs than at the 38 hospitals without such programs. Hospitals with residency programs had higher average annual patient volumes (104 vs 66). In an analysis simultaneously adjusting for patient characteristics, volume, and presence of a residency program, neither volume (odds ratio [OR] per 10 additional cases treated 1.01, 95% confidence interval [CI], .98 to 1.04) nor presence of a pediatric residency program (OR 1.18, 95% CI, .94 to 1.47) was significantly associated with neonatal mortality risk.

CONCLUSION

There are differences in neonatal mortality rates among NICUs that cannot be explained by differences in the measured admission characteristics of the infants, suggesting that the effectiveness of medical care varies among units. Neither the annual volume of very low birth weight infants treated in a unit nor the presence of a pediatric residency training program was independently associated with neonatal mortality rates for very low birth weight infants.

Functional associations of "trouble seeing"

The purpose of this study was to determine how vision problems affect health status. The information was collected in 1990 from 2,249 household heads and spouses over 50 years of age during an annual survey of a nationally representative sample that was adjusted for attrition and nonresponse. Vision problems were defined as "trouble seeing (even with glasses or contact lenses)." Health status was measured principally with the Medical Outcomes Study Short-Form 36. Regression analyses found a significant relationship between "trouble seeing" and each of five health-status domains. We conclude that it may not be appropriate to require specific functional limitations as a precondition for cataract surgery and that instruments for measuring functional disabilities related to vision should include more general questions.

Reproductive history, socioeconomic status, and self-reported health status of women aged 50 years or older

OBJECTIVES

This paper describes the relationship between self-reported general health status and several facets of reproductive history.

METHODS

We analyzed survey data on a national probability sample of 1341 women aged 50 and older from the Panel Study of Income Dynamics. We used multivariate regression techniques to control for differences in health indices that assessed health status and functioning.

RESULTS

Women with a history of six or more completed pregnancies were found to be disadvantaged in educational attainment, financial resources, and health status compared with women with no or fewer pregnancies. When current sociodemographic factors were controlled, six or more pregnancies were associated with worse general health and worse physical role functioning. When sociodemographic factors and number of births were controlled, among women with at least one delivery, women who had experienced an infant's death reported worse health as measured by all three indices. Women with a first delivery before the age of 18 were more likely to report a functional limitation.

CONCLUSIONS

Women with high parity status, a history of an infant's death, and an early first pregnancy may be at greater risk of poor health in later life.

Heart rate power spectral analysis in patients before and 6 weeks after coronary artery bypass grafting

Decreased cardiac vagal activity is a known risk factor in coronary artery disease. The aim of our study was to determine the effect of coronary artery bypass grafting (CABG) on heart rate variability (HRV) before and 6 weeks after CABG. The study group consisted of 34 patients (4 women, 30 men, mean age 56 +/- 9 years). ECGs were recorded in 10 minutes periods in both supine and standing position with controlled breathing rate (0.25Hz). The analysis of HRV power spectrum was done by means of fast Fourier transformation. The total spectral power (TPS), power in very low frequency band (VLF: < 0.05 Hz), low frequency band (LF:0.05-0.15Hz), high frequency band (HF:0.15-0.5Hz), LF/HF ratio and percentage fraction of total power in these frequency bands (%VLF, %LF, %HF) were analysed. Significant attenuation of all spectral components of HRV were found during orthostatic load before CABG (p < 0.05). TPS, VLF, LF, %HF decreased in standing position to about half of their level in supine position, HF decreased to as little as one fourth, while LF/HF ratio and %LF increased significantly (p < 0.05). After the CABG these changes were not significant. We have found significant increase of HF (p < 0.05) and %HF (p < 0.01) in standing position after the CABG. The results suggest that CABG causes an improvement in cardiac vagal activity especially in standing position.

Dental expenditures and insurance coverage among older adults

Using data on 975 elderly persons from the 1990 Health Supplements to the Panel Study of Income Dynamics, we describe the predictors of expenditures for dental services. Forty-four percent of elderly persons reported using some dental services within a year. Thirteen percent had private dental insurance, and 8% had a separate dental policy. The average total expenditure for those who used any dental services was $378, 88% of which was paid out-of-pocket. Persons with a separate dental insurance policy, younger and better educated persons, and those with greater financial resources were more likely to use dental services.

Sociodemographic and health factors in driving patterns after 50 years of age

Data from the 1990 Panel Study of Income Dynamics were used to predict, by means of logistic regression, the likelihood that people who had previously driven would continue to drive and to drive after dark after 50 years of age. The results support the conclusion that driving patterns appear to be explained partly by a combination of sociodemographic factors and health status. Furthermore, it is shown that those reported to drive for nondrivers appear to be the same individuals known to provide most informal support for functionally impaired elderly people.

Aneurysm of the abdominal aorta ruptured to the retroperitoneal space and inferior vena cava. Case report

Case of sixty-six year old male with abdominal aortic aneurysm rupturing into the retroperitoneal space and inferior vena cava is presented because of its rarity. Patient was operated upon with initial success but died probably due to pulmonary embolism with thrombus originating from the inferior vena cava narrowed at surgery.

Supervised six-months treatment of newly diagnosed pulmonary tuberculosis using isoniazid, rifampin, and pyrazinamide with and without streptomycin

In a previous study, we have shown that a 6-month regimen consisting of 2 months of isoniazid, rifampin, pyrazinamide, and streptomycin administered daily (2IRSZ) followed by 4 months of isoniazid and rifampin administered twice weekly (4I2R2) yielded no relapses after 30 months of follow-up. In order to assess the contribution of streptomycin to this treatment regimen, 213 patients with newly detected smear-positive pulmonary tuberculosis were randomly assigned to the following two 6-month treatment regimens: 2IRZ/4I2R2 and 2IRSZ/4I2R2. One hundred seventy-two of the 213 patients (81%) completed therapy, i.e., 116 of 135 patients (86%) treated with 2IRZ/4I2R2 and 56 of 78 patients (72%) treated with 2IRSZ/4I2R2. Adverse reactions requiring withdrawal of drugs for 7 days or longer were observed in 4.2% of patients (3.7% receiving the 2IRZ/4I2R2 regimen and 5.1% receiving the 2IRSZ/4I2R2 regimen). At the end of treatment, all patients in the 2IRZ/I2R2 series had negative smears and cultures. Two of the 116 patients (1.7%) in the 2IRZ/I2R2 series developed isoniazid resistance in the fourth month of treatment and remained sputum positive at the end of treatment. In the follow-up period, 4 patients (3.4%) treated with 2IRZ/4I2R2 relapsed and 1 (1.8%) treated with 2IRSZ/4I2R2 relapsed. The only significant difference between the 2 regimens was the higher dropout rate among those assigned to the 2IRSZ/4I2R2 regimen.