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Managed care and preventable hospitalization among Medicaid adults.

OBJECTIVE: The study examines the association between managed care enrollment and preventable hospitalization patterns of adult Medicaid enrollees hospitalized in four states. DATA SOURCES/STUDY SETTING: Hospital discharge data from the Healthcare Cost and Utilization Project (HCUP) database of the Agency for Healthcare Research and Quality (AHRQ) for New York (NY), Pennsylvania (PA), Wisconsin (WI), and Tennessee (TN) residents in the age group 20-64 hospitalized in those states, linked to the Area Resource File (ARF) and American Hospital Association (AHA) survey files for 1997. STUDY DESIGN: The study uses separate logistic models for each state comparing preventable admissions with marker admissions (urgent, insensitive to primary care). The model controls for socioeconomic and demographic variables, and severity of illness. PRINCIPAL FINDINGS: Consistently in different states, private health maintenance organization (HMO) enrollment was associated with fewer preventable admissions than marker admissions, compared to private fee-for-service (FFS). However, Medicaid managed care enrollment was not associated with a reduction in preventable admissions, compared to Medicaid FFS. CONCLUSIONS: Our analysis suggests that the preventable hospitalization pattern for private HMO enrollees differs significantly from that for commercial FFS enrollees. However, little difference is found between Medicaid HMO enrollees and Medicaid FFS patients. The findings did not vary by the level of Medicaid managed care penetration in the study states.

Adult↗

Prostate cancer detection in men with prior high grade prostatic intraepithelial neoplasia or atypical prostate biopsy.

PURPOSE: We used clinical variables to predict prostate cancer detection on re-biopsy among patients diagnosed with high grade prostatic intraepithelial neoplasia (PIN) or atypia on initial prostate biopsy. MATERIALS AND METHODS: A total of 45 men with atypia and 43 with high grade PIN were eligible for our study. Clinical variables were tested with univariate and multivariate logistic regression to predict who would have cancer on re-biopsy. We also calculated the odds of detecting cancer with various repeat sampling strategies and determined whether the location of initial atypia or high grade PIN is correlated to that of cancer on re-biopsy. RESULTS: Of the patients in the atypia and high grade PIN groups 51% had cancer on re-biopsy. Cancer was diagnosed significantly earlier in the high grade PIN than in the atypia cohort (average 7.5 versus 22.9 months, respectively, p = 0.005). Multivariate logistic modeling showed that digital rectal examination and patient age were independent predictors of cancer in atypia, whereas no variables were significantly predictive for high grade PIN. Of cancers in the atypia and high grade PIN 65% and 74%, respectively, would have been detected if re-biopsy was focused only at the initial site of disease. CONCLUSIONS: Men with atypia or high grade PIN merit close followup because 50% will have cancer on re-biopsy as will those who are older with an abnormal digital rectal examination. Although re-biopsy should focus primarily on the original site of atypia or high grade PIN, cancer detection significantly increases with the sampling of adjacent sites.

Aged↗

The risk for early-adulthood anxiety and depressive disorders in adolescents with anxiety and depressive disorders.

BACKGROUND: Various studies find relationships among anxiety and depressive disorders of adolescence and adulthood. This study prospectively examines the magnitude of longitudinal associations between adolescent and adult anxiety or depressive disorders. METHODS: An epidemiologically selected sample of 776 young people living in upstate New York received DSM-based psychiatric assessments in 1983, 1985, and 1992 using structured interviews. The magnitude of the association between adolescent and adult anxiety or depressive disorders was quantified using odds ratios generated from logistic regression analyses and from a set of latent Markov analyses. We focus on longitudinal associations among narrowly defined DSM anxiety or depressive disorders. RESULTS: In simple logistic models, adolescent anxiety or depressive disorders predicted an approximate 2- to 3-fold increased risk for adulthood anxiety or depressive disorders. There was evidence of specificity in the course of simple and social phobia but less specificity in the course of other disorders. Results from the analyses using latent variables suggested that while most adolescent disorders were no longer present in young adulthood, most adult disorders were preceded by adolescent disorders. CONCLUSIONS: An anxiety or depressive disorder during adolescence confers a strong risk for recurrent anxiety or depressive disorders during early adulthood. Most anxiety and depressive disorders in young adults may be preceded by anxiety or depression in adolescence.

Adolescent↗

Thirty-year projections for deaths from ischemic stroke in the United States.

BACKGROUND AND PURPOSE: The age adjustment of stroke mortality rates may obscure the impact of population changes on the total burden of disease. Deaths from ischemic stroke may rise unless future declines in stroke death rates offset the projected growth in high-risk populations. METHODS: Using data on ischemic stroke mortality from the National Center of Health Statistics for 1979 to 1998, we fit a logistic model to predict changes in stroke death rates as a function of time for each of 42 sex-race-age groups. Using population projections from the US Census Bureau, we then calculated the expected number of deaths in the United States from ischemic stroke over the next 30 years on the basis of age, sex, and race. RESULTS: Models generally fit historical data well (median R2=0.81; interquartile range, 0.43 to 0.97) and consistently predicted small declines in future death rates. The total predicted number of stroke deaths increased by 98% from 139,000 in 2002 to 275,000 in 2032, whereas the total US population was projected to increase by only 27% in the same period. The largest percentage increases in stroke deaths were predicted to occur in blacks (134%) and nonwhite, nonblack races (221%). CONCLUSIONS: If recent trends in ischemic stroke mortality continue, increases in US stroke deaths will outpace overall population growth, with a doubling in deaths over the next 30 years.

Adolescent↗

After-hours discharges from intensive care are associated with increased mortality.

OBJECTIVE: To investigate the change in pattern of discharge of patients from an intensive care unit (ICU) to hospital wards and to determine the impact of discharge time on subsequent hospital mortality. DESIGN AND PARTICIPANTS: A retrospective cohort study of 10 903 patients discharged alive from a single ICU between 1 January 1992 and 31 December 2002. MAIN OUTCOME MEASURE: In-hospital mortality. RESULTS: Of the 10 903 patients discharged alive from the ICU, 486 (4.5%) died in hospital wards. When discharge times were categorised according to nursing shift (morning, 07:00-14:59; afternoon, 15:00-21:59; and night, 22:00-06:59), patients were more likely to be discharged on an afternoon shift (odds ratio, 3.63; 95% CI, 3.05-4.30) or night shift (4.52; 95% CI, 3.15-6.64) in 2000-2002 compared with 1992-1994. In a multiple logistic model, hospital mortality after discharge from the ICU was increased by higher APACHE II score (1.14; 95% CI, 1.12-1.16); admission to ICU from the operating room (1.47; 95% CI, 1.11-1.95) and from the general ward (1.75; 95% CI, 1.37-2.23); and discharge during the afternoon (1.36; 95% CI, 1.08-1.70) and night shifts (1.63; 95% CI, 1.03-2.57). CONCLUSION: Over an 11-year period, more patients are being discharged from the ICU in the afternoon and night suggesting increasing pressure on ICU beds. Patients discharged on these shifts have an increased risk of death.

Adolescent↗

Farm-management and milking practices associated with the presence of Listeria monocytogenes in New York state dairy herds.

Knowledge of the relationship between dairy herd management and milking practices with the occurrence of Listeria monocytogenes on dairy farms might assist in the development of intervention strategies aimed at eliminating this organism at the pre-harvest dairy-food-production level. This paper represents a first step towards that goal. We carried out a cross-sectional study to identify farm factors that were associated with isolation of L. monocytogenes from on-farm in-line milk-filters. Data on these factors were collected by personal interview of the farm owners or managers. Logistic regression was used to evaluate the significance of association of each factor while simultaneously controlling for the presence of other factors. A systematic approach was developed in which the bivariable association of the hypothesized factors initially was evaluated. All significant factors were then jointly evaluated in a multivariable logistic model. Farms that used a bucket system had significantly higher odds of L. monocytogenes as compared to farms that used a round-the-barn pipeline milking system (OR=0.35,P=0.05) or milking parlor (OR=0.21,P=0.01). There was a significant association between pre-milking teat disinfection (OR=0.26,P=0.001) and pre-milking examination of abnormal appearance of milk (OR=0.4,P=0.01) against the occurrence of L. monocytogenes. We also found a significant association between the use of E. coli J5 vaccine (OR=3.3,P=0.03) and how long dry-cow therapy had been used on farm (OR=0.34,P=0.04).

Animal Husbandry↗

Ondansetron versus metoclopramide in the treatment of postoperative nausea and vomiting.

In this prospective, randomized, double-blind study, we compared the efficacy and safety of ondansetron and metoclopramide in the treatment of postoperative nausea and vomiting (PONV). One hundred seventy-five patients with PONV during recovery from anesthesia for gynecological laparoscopy were treated intravenously with either ondansetron 4 mg (58 patients), metoclopramide 10 mg (57 patients), or placebo (60 patients). Early antiemetic efficacy (abolition of vomiting within 10 min and of nausea within 30 min from the administration of the study drugs with no further vomiting or nausea episodes during the first hour) was obtained in 54 of 58 patients (93.1%) in the ondansetron group, in 38 of 57 patients (66.7%) in the metoclopramide group, and in 21 of 60 patients (35%) in the placebo group (P < 0.001). This difference was still significant when controlling for age, body weight, history of motion sickness, previous PONV episodes, duration of anesthesia, and intraoperative fentanyl consumption using a logistic model. Early antiemetic efficacy was inversely related to the amount of fentanyl administered during anesthesia, regardless of treatment. According to the Kaplan-Meier method, the probability of remaining PONV-free for 48 h after a successful treatment was 0.59 (95% confidence interval 0.45-0.71) in the ondansetron group, 0.45 (0.29-0.60) in the metoclopramide group, and 0.33 (0.15-0.53) in the placebo group (P = 0.003). In conclusion, ondansetron 4 mg is more effective than metoclopramide 10 mg and placebo in the treatment of established PONV.

Adolescent↗

Analysis of factors affecting uptake of Tc-99m Sn-N-pyridoxyl-5-methyltryptophan by hepatocellular carcinoma.

We performed Tc-99m PMT imaging in 176 patients with HCC and evaluated factors affecting 99mTc-PMT uptake by HCC with a logistic model. The probability of HCC showing increase in uptake of the radioisotope was 104.6 times higher in patients with the Ed I type than in those with the Ed III type and 12.1 times higher in patients with a tumor diameter of 5.0-7.9 cm than in those with a tumor diameter of 2.0-5.0 cm. Among the other variables, the serum AFP level and sex were suggested to have effects similar to those of the tumor size on Tc-99m PMT uptake by HCC. The grade of morphological differentiation of the tumor was therefore most markedly related to Tc-99m PMT uptake.

Age Factors↗

Orthotopic heart transplantation for failing single ventricle physiology.

OBJECTIVE: Evaluation of incremental risk factors for early mortality in children undergoing orthotopic heart transplantation (OHT) for failing single ventricle physiology. METHODS: Between 1988 and 2002, 25 patients (mean age 9.3+/-7.1 years) underwent OHT for complex congenital heart disease (CHD) with a functional right (15 patients) or left (10 patients) single ventricle. Palliative staging towards Fontan completion had been previously accomplished in 22 patients (88%). Transition to OHT occurred from a shunt stage in 10, a bi-directional cavopulmonary anastomosis (BDG) stage in nine, and after Fontan failure in six patients. RESULTS: Thirty-day survival was 68.0+/-9.3% with no additional mortality up to 14.1 years. OHT following BDG staging exhibited 100% long-term survival, as opposed to 66.7+/-15.7% for OHT after systemic-to-pulmonary shunt, and 33.3+/-19.2% for OHT following failing Fontan (p=0.032). Regression logistic modelling indicated failing Fontan circulation as predictor of higher mortality after OHT (p=0.041). Reintervention was necessary in four patients 40+/-11 months after OHT to address residual superior vena cava (two) and isthmic (two) stenosis. Overall freedom from reintervention was 88.3+/-8.1% at 5 years. CONCLUSIONS: OHT for structural CHD with single ventricle physiology entails substantial early mortality while BDG enables the best transition to heart transplant. OHT should be considered in the decision-making process as an alternative to Fontan completion in high-risk candidates, since rescue-OHT after failing Fontan seems unwarranted.

Adolescent↗

Can a pain management and palliative care curriculum improve the opioid prescribing practices of medical residents?

BACKGROUND: Although opioids are central to acute pain management, numerous studies have shown that many physicians prescribe them incorrectly, resulting in inadequate pain management and side effects. We assessed whether a case-based palliative medicine curriculum could improve medical house staff opioid prescribing practices. DESIGN: Prospective chart review of consecutive pharmacy and billing records of patients who received an opioid during hospitalization before and after the implementation of a curricular intervention, consisting of 10 one-hour case-based modules, including 2 pain management seminars. MEASUREMENTS: Consecutive pharmacy and billing records of patients who were cared for by medical residents (n = 733) and a comparison group of neurology and rehabilitative medicine patients (n = 273) that received an opioid during hospitalization in 8-month periods before (1/1/97 to 4/30/97) and after (1/1/99 to 4/30/99) the implementation of the curriculum on the medical service were reviewed. Three outcomes were measured: 1) percent of opioid orders for meperidine; 2) percent of opioid orders with concomminant bowel regimen; and 3) percent of opioid orders using adjuvant nonsteroidal anti-inflammatory drugs (NSAIDs). MAIN RESULTS: The percentage of patients receiving meperidine decreased in the study group, but not in the comparison group. The percentages receiving NSAIDs and bowel medications increased in both groups. In multivariate logistic models controlling for age and race, the odds of an experimental group patient receiving meperidine in the post-period decreased to 0.55 (95% confidence interval [95% CI], 0.32 to 0.96), while the odds of receiving a bowel medication or NSAID increased to 1.48 (95% CI, 1.07 to 2.03) and 1.53 (95% CI, 1.01 to 2.32), respectively. In the comparison group models, the odds of receiving a NSAID in the post-period increased significantly to 2.27 (95% CI, 1.10 to 4.67), but the odds of receiving a bowel medication (0.45; 95% CI, 0.74 to 2.00) or meperidine (0.85; 95% CI, 0.51 to 2.30) were not significantly different from baseline. CONCLUSIONS: This palliative care curriculum was associated with a sustained (>6 months) improvement in medical residents' opioid prescribing practices. Further research is needed to understand the changes that occurred and how they can be translated into improved patient outcomes.

Aged↗

Hemodialysis-associated hypotension as an independent risk factor for two-year mortality in hemodialysis patients.

BACKGROUND: The relationship between blood pressure (BP) and mortality in hemodialysis patients has remained controversial. Some studies suggested that a lower pre- or postdialysis BP was associated with excess mortality, while others showed poorer outcome in patients with uncontrolled hypertension. We conducted a multicenter prospective cohort study to evaluate the impact of hemodialysis-associated hypotension on mortality. METHODS: We recruited 1244 patients (685 males; mean age, 60 +/- 13 years) who underwent hemodialysis in 28 units during the two-year study period beginning in December 1999. Pre-, intra-, and postdialysis BP, and BP upon standing soon after hemodialysis, were measured in all patients at entry. Logistic regression analysis was used to assess the effect on mortality of pre-, intra-, and postdialysis BP, a fall in BP during hemodialysis, and a fall in BP upon standing soon after hemodialysis. RESULTS: During the study period, 149 patients died. Logistic models identified the lowest intradialysis systolic blood pressure (SBP) and degree of fall in SBP upon standing soon after hemodialysis as significant factors affecting mortality, but not pre- or postdialysis SBP and diastolic BP. The adjusted odds ratio for death was 0.79 (95% CI 0.64-0.98) when the lowest intradialysis SBP was analyzed in increments of 20 mm Hg, and was 0.82 (95% CI 0.67-0.98) when the fall in SBP upon standing soon after hemodialysis was analyzed in increments of 10 mm Hg. CONCLUSION: These results suggest that intradialysis hypotension and orthostatic hypotension after hemodialysis are significant and independent factors affecting mortality in hemodialysis patients.

Aged↗

Do allelic variants in alpha2A and alpha2C adrenergic receptors predispose to hypertension in blacks?

Sequence variations in the human alpha2 adrenergic receptor genes (ADRA2A and ADRA2C) have been implicated as a cause of hypertension in blacks. Although certain alleles are selectively enriched in blacks, their association with hypertension is based on small convenience samples and has not been evaluated in larger populations. From a stratified random population sample of 3398 individuals (52% blacks), we obtained DNA samples together with an in-home health interview, 10 in-home measurements of blood pressure, and cardiac MRI. We tested for associations among hypertension, untreated blood pressure, and parameters of hypertensive heart disease with 2 alleles, a DraI restriction fragment length polymorphism in the ADRA2A gene and a deletion of residues 322 to 325 in the ADRA2C gene. Although both alleles were selectively enriched in this black population, we found no association of either allele with hypertension, untreated blood pressure, or any of the cardiac function parameters. In a logistic model that controlled for age, body mass index, diabetes, and smoking, the adjusted odds ratio (OR) for hypertension was 1.0 (95% CI, 0.8 to 1.2), and 1.0 (95% CI, 0.9 to 1.2) for ADRA2A and ADRA2C variant alleles. In subjects not receiving prescription blood pressure medication, neither of these alleles, alone or in combination, was predictive of blood pressure, heart rate, left ventricular mass, cardiac output, systemic vascular resistance, or aortic compliance. Both the DraI restriction fragment length polymorphism in ADRA2A and the ADRA2C (Del 322 to 325) can be excluded as major candidate alleles for hypertension in blacks.

Adult↗

Spirometrically gated high-resolution CT findings in COPD: lung attenuation vs lung function and dyspnea severity.

STUDY OBJECTIVES: The aim of this study was to investigate the relationship between high-resolution CT (HRCT) lung attenuation measurements, acquired under spirometric control of inspiratory and expiratory lung volume, and pulmonary dysfunction as well as dyspnea severity in patients with COPD. PATIENTS AND DESIGN: In 51 patients with COPD, we compared by linear regression, univariate and multivariate logistic regression airflow limitation (FEV(1)/vital capacity [VC]), hyperinflation (percentage of predicted residual volume [RV%]), parenchymal loss (percentage of predicted diffusing capacity of the lung for carbon monoxide [Dlco%]), and Medical Research Council (MRC) dyspnea scale with relative area with attenuation values < - 950 HU at 90% of VC [RAI(950)] and < - 910 HU at 10% of VC, respectively, and with mean lung attenuation measured at the same levels of VC (mean CT lung density at 10% of VC, and mean CT lung density at 90% of VC [MeanCTEXP]). RESULTS: All HRCT attenuation measurements were significantly related with functional abnormalities and dyspnea severity. In multivariate logistic models, with 1 indicating worse changes in dichotomous outcome variables, MeanCTEXP independently predicted FEV(1)/VC (odds ratio [OR], 0.24; 95% confidence interval [CI], 0.11 to 0.56), RV% (OR, 0.57; 95% CI, 0.42 to 0.77), and MRC dyspnea scale (OR, 0.63; 95% CI, 0.48 to 0.82), while RAI(950) independently predicted Dlco% (OR, 1.90; 95% CI, 1.37 to 2.65). CONCLUSIONS: Spirometrically gated measurements of HRCT lung attenuation reflect differently functional changes and dyspnea perception in COPD. Inspiratory measurements assess the extent of emphysematous tissue loss, and expiratory measurements may reflect airflow limitation and lung hyperinflation with attendant dyspnea perception. Pulmonary dysfunction in COPD cannot be assessed by a single modality of lung attenuation measurement.

Adult↗

Exposure to acellular blood products and risk of HIV infection in hemophiliacs from Belo Horizonte, Brazil.

Results of a HIV prevalence study conducted in hemophiliacs from Belo Horizonte, Brazil are presented. History of exposure to acellular blood components was determined for the five year period prior to entry in the study, which occurred during 1986 and 1987. Patients with coagulations disorders (hemophilia A = 132, hemophilia B = 16 and coagulation disorders other than hemophilia = 16) were transfused with liquid cryoprecipitate, locally produced, lyophilized cryoprecipitate, imported from São Paulo (Brazil) and factor VIII and IX, imported from Rio de Janeiro (Brazil), Europe, and United States. Thirty six (22%) tested HIV seropositive. The univariate and multivariate analysis (logistic model) demonstrated that the risk of HIV infection during the study period was associated with the total units of acellular blood components transfused. In addition, the proportional contribution of the individual components to the total acellular units transfused, namely a increase in factor VIII/IX and lyophilized cryoprecipitate proportions, were found to be associated with HIV seropositivity. This analysis suggest that not only the total amount of units was an important determinant of HIV infection, but that the risk was also associated with the specific component of blood transfused.

Adolescent↗

Black women receive less mammography even with similar use of primary care.

BACKGROUND: Black women with breast cancer have a decreased 5-year survival rate in comparison with white women, possibly because of less frequent use of mammography. Having a regular provider or source of health care is the most important determinant of mammography use. OBJECTIVE: To examine whether the difference in mammography use between elderly black women and elderly white women is related to the number of visits made to a primary care physician. DESIGN: Retrospective review of 1990 Health Care Financing Administration billing files (Medicare part B) from 10 states. SETTING: Outpatient mammography services in 10 states. PARTICIPANTS: Black women and white women, 65 years of age and older, residing in one of the 10 states. MEASUREMENTS: Any mammogram. Predictors included race, number of visits to a primary care physician (0, 1, 2, or 3 or more), median income of ZIP code of residence (a surrogate measure of income), and state. RESULTS: The following are findings from Georgia; similar results were found in each state studied. The mean age of the 335,680 women was 75 years; 20% were black. Sixty-eight percent of the black women and 69% of the white women made at least one visit to a primary care physician. Overall, 14% of the women had had mammography; black women had mammography less often than white women (9% compared with 15%). At each primary care visit level (1, 2, or 3 or more visits), black women had mammography less often than white women (1 visit, 7% compared with 15%; 2 visits, 12% compared with 21%; and 3 or more visits, 12% compared with 20%). Even among women who had made at least one visit to a primary care physician, a deficit for blacks occurred in each income quintile (lowest quintile, 13% compared with 20%; low, 10% compared with 18%; middle, 12% compared with 18%; high, 10% compared with 19%; and highest, 12% compared with 22%) and in each state (in Georgia, for example, the percentages were 14% compared with 21%). An age-, income-, and state-adjusted logistic model predicting mammography use for 2.9 million white women in all 10 states shows the powerful effect of primary care use on mammography (odds ratios for 1, 2, and 3 or more visits were, respectively, 2.73 [95% CI, 2.70 to 2.77]; 3.98 [CI, 3.93 to 4.03]; and 4.62 [CI, 4.58 to 4.67]). The same model fit to 250 000 black women shows a lesser effect (analogous odds ratios were 1.77 [CI, 1.67 to 1.87]; 2.49 [CI, 2.36 to 2.63]; and 3.15 [CI, 3.04 to 3.25]). CONCLUSION: Among older women, mammography is used less often for blacks than for whites. More frequent use of mammography is associated with more visits to a primary care physician in both groups, but the deficit for black women persists at each income level and in each state, even after primary care use is considered. Primary care visits are less likely to "boost" mammography use for black women than for white women.

Black or African American↗

[Automated complex diagnosis and choice of treatment method in benign prostatic hyperplasia].

The paper deals with rational choice of conservative and surgical treatment of patients with benign prostatic hyperplasia (BPH), based on an automatic diagnostic approach and realization of four stages of a logistic model of choice of BPH treatment policy with individual features of the status of urological patients being borne in mind. The procedure was tested in 72 patients from a Voronezh regional clinical hospital of the South-Western Railway, in 92 patients from a Voronezh regional clinical treatment-and-diagnosis center. The values of informative parameters were obtained on the basis of computer-aided patients' self-testing, results of baseline examinations, up-to-date non-invasive studies of the prostate: urofluometry, ultrasound bilocation, MR tomography, etc. The findings lead to the conclusion that integration of computer technologies and up-to-date medical equipment is promising for enhancing the quality of diagnosis and treatment of BPH.

Diagnosis, Computer-Assisted↗

Influence of cardiopulmonary resuscitation prior to defibrillation in patients with out-of-hospital ventricular fibrillation.

CONTEXT: Use of automated external defibrillators (AEDs) by first arriving emergency medical technicians (EMTs) is advocated to improve the outcome for out-of-hospital ventricular fibrillation (VF). However, adding AEDs to the emergency medical system in Seattle, Wash, did not improve survival. Studies in animals have shown improved outcomes when cardiopulmonary resuscitation (CPR) was administered prior to an initial shock for VF of several minutes' duration. OBJECTIVE: To evaluate the effects of providing 90 seconds of CPR to persons with out-of-hospital VF prior to delivery of a shock by first-arriving EMTs. DESIGN: Observational, prospectively defined, population-based study with 42 months of preintervention analysis (July 1, 1990-December 31, 1993) and 36 months of post-intervention analysis (January 1, 1994-December 31, 1996). SETTING: Seattle fire department-based, 2-tiered emergency medical system. PARTICIPANTS: A total of 639 patients treated for out-of-hospital VF before the intervention and 478 after the intervention. INTERVENTION: Modification of the protocol for use of AEDs, emphasizing approximately 90 seconds of CPR prior to delivery of a shock. MAIN OUTCOME MEASURES: Survival and neurologic status at hospital discharge determined by retrospective chart review as a function of early (<4 minutes) and later (> or =4 minutes) response intervals. RESULTS: Survival improved from 24% (155/639) to 30% (142/478) (P=.04). That benefit was predominantly in patients for whom the initial response interval was 4 minutes or longer (survival, 17% [56/321] before vs 27% [60/220] after; P = .01). In a multivariate logistic model, adjusting for differences in patient and resuscitation factors between the periods, the protocol intervention was estimated to improve survival significantly (odds ratio, 1.42; 95% confidence interval, 1.07-1.90; P = .02). Overall, the proportion of victims who survived with favorable neurologic recovery increased from 17% (106/634) to 23% (109/474) (P = .01). Among survivors, the proportion having favorable neurologic function at hospital discharge increased from 71% (106/150) to 79% (109/138) (P<.11). CONCLUSION: The routine provision of approximately 90 seconds of CPR prior to use of AED was associated with increased survival when response intervals were 4 minutes or longer.

Aged↗

Early changes in respiratory compliance and resistance during the development of bronchopulmonary dysplasia in the era of surfactant therapy.

Despite the availability of surfactant treatment, extremely low birth weight (ELBW) infants continue to be at high risk of developing bronchopulmonray dysplasia (BPD). Evidence suggests that pathologic changes occur within the first few days of life. We hypothesized that the changes in early respiratory system compliance and resistance in ELBW infants with or without hyaline membrane disease (HMD) would correlate with BPD severity and aid in its prediction. Respiratory system compliance (Crs) and resistance (Rrs) were measured at the end of weeks 1, 2, 3, and 4 in 46 infants weighing 1,000 g or less at birth, using the single breath airway occlusion method. Twenty-four infants had HMD and 22 did not. Fifteen infants with and 10 infants without HMD developed BPD with radiological changes and oxygen needs at 28 days. Twelve BPD infants required supplemental oxygen beyond 36 weeks, defined as chronic lung disease (CLD). Irrespective of whether the infant initially had HMD, the week 1 results showed that infants who subsequently developed BPD had a significantly higher respiratory system resistance than those who did not (P = 0.0014). Though week 1 compliance was lower, it was not statistical significant. Multiple logistic models consisting of simple neonatal variables and week 1 respiratory mechanics showed that Rrs was independently associated with subsequent BPD (P = 0.026) and CLD (P = 0.016), while compliance was not. Prediction of CLD improved with the inclusion of Rrs results as compared to prediction using clinical variables alone. Throughout the 4-week study period, Rrs was significantly higher in BPD infants than in those without BPD, and resistance was particularly abnormal in those who had CLD or subsequently required corticosteroid treatment. These observations provide rationale for interventions to prevent BPD within the first week of life. Respiratory mechanics measurements could be useful in the assessment of therapeutics in the current surfactant era.

Airway Resistance↗