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1.
J Am Diet Assoc ; 109(8): 1406-10, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19631047

ABSTRACT

The impact of heart failure and its treatment on specific nutrient requirements is unknown. Furthermore, depletion of water-soluble B vitamins that play key roles in the production of cellular energy in patients with heart failure can contribute to depletion of energy reserves observed in the failing heart. A cross-sectional study recently reported that approximately one third of hospitalized patients with heart failure had tissue levels suggestive of thiamin deficiency (vitamin B-1). Riboflavin (vitamin B-2) and pyridoxine (vitamin B-6) are similar to thiamin in that they are water-soluble, subject to renal excretion, have limited tissue storage, and are dependent on intake. Therefore, it was hypothesized that the status of these B vitamins may also be adversely affected by heart failure. As a result, the prevalence of patients at risk of vitamin B-2 (erythrocyte glutathione reductase activity coefficient > or = 1.2) and B-6 deficiency (plasma B-6 < or = 20 nmol/L) was determined in a cross-section of 100 patients hospitalized with heart failure between April 2001 and June 2002 as well as in a group of volunteers without heart failure. Twenty-seven percent of patients with heart failure had biochemical evidence of vitamin B-2 deficiency, while 38% had evidence of B-6 deficiency. These prevalence rates were significantly higher than those observed in the volunteers without heart failure (2% and 19%, respectively; P < or = 0.02). Use of common B-vitamin-containing supplements by patients with heart failure did not significantly reduce deficiency rates in comparison with those who did not use supplements (B-2 P=0.38 or B-6 P=0.18)). Finally, while 80% of patients with heart failure took diuretics, neither the dose nor the duration of furosemide use was related to the presence of either B-2 or B-6 deficiency. Given the physiologic importance of these vitamins, further investigations aimed at determining the effect of heart failure on specific nutrient requirements as well as the safety and efficacy of B-vitamin supplementation are warranted.


Subject(s)
Heart Failure/blood , Nutritional Requirements , Nutritional Status , Riboflavin Deficiency/epidemiology , Vitamin B 6 Deficiency/epidemiology , Aged , Chi-Square Distribution , Cross-Sectional Studies , Dietary Supplements , Female , Heart Failure/epidemiology , Heart Failure/etiology , Hospitalization , Humans , Logistic Models , Male , Middle Aged , Odds Ratio , Ontario/epidemiology , Prevalence , Riboflavin/administration & dosage , Riboflavin/blood , Riboflavin Deficiency/blood , Riboflavin Deficiency/drug therapy , Risk Factors , Statistics, Nonparametric , Thiamine/administration & dosage , Thiamine/blood , Thiamine Deficiency/blood , Thiamine Deficiency/drug therapy , Thiamine Deficiency/epidemiology , Vitamin B 6/administration & dosage , Vitamin B 6/blood , Vitamin B 6 Deficiency/blood , Vitamin B 6 Deficiency/drug therapy
2.
Chest ; 135(3): 678-687, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19265087

ABSTRACT

BACKGROUND: Survivors of ARDS have well documented physical limitations, but psychological effects are less clear. We determined the prevalence of self-reported depression and memory dysfunction in ARDS survivors. METHODS: Six to 48 (median 22) months after ICU discharge, we administered instruments assessing depression symptoms (Beck Depression Inventory-II [BDI-II]) and memory dysfunction (Memory Assessment Clinics Self-Rating Scale [MAC-S]) to 82 ARDS patients who were enrolled in a prospective cohort study in four university-affiliated ICUs. RESULTS: Sixty-one (74%), 64 (78%), and 61 (74%) patients fully completed the BDI-II, MAC-S (Ability subscale), and MAC-S (Frequency of Occurrence subscale) instruments. Responders (similar to nonresponders) were young (median 42 years, interquartile range [IQR] 35 to 56), with high admission illness severity and organ dysfunction. The median BDI-II score was 12 (IQR 5 to 25). Twenty-five (41%) patients reported moderate-severe depression symptoms and were less likely to return to work than those with minimal-mild symptoms (8/25 [32%] vs 25/36 [69%]; p = 0.005). Median MAC-S (Ability) and MAC-S (Frequency of Occurrence) scores were 76 (IQR 61 to 93) and 91 (IQR 77 to 102), respectively; 8%, 16%, and 20% scored > 2, > 1.5, and > 1 SD(s), respectively, below age-adjusted population norms for each subscale. BDI-II and MAC-S scores were negatively correlated (Spearman coefficient -0.58 and -0.50 for Ability and Frequency of Occurrence subscales, respectively; p < 0.0001). Univariable analyses showed no demographic or illness-severity predictors of BDI-II (including the Cognitive subscale) or MAC-S (both subscales); results were similar when restricted to patients whose primary language was English. CONCLUSIONS: ARDS survivors report a high prevalence of depression symptoms and a lower prevalence of memory dysfunction 6 to 48 months after ICU discharge. Depression symptoms may hinder the return to work, or patients may report these symptoms because of inability to re-enter the workforce.


Subject(s)
Depressive Disorder/etiology , Memory Disorders/etiology , Respiratory Distress Syndrome/psychology , APACHE , Adult , Aged , Female , Humans , Male , Middle Aged , Self-Assessment , Surveys and Questionnaires
3.
Can J Cardiol ; 24(9): 677-82, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18787717

ABSTRACT

BACKGROUND: Disadvantaged inner-city populations have significantly higher cardiovascular disease (CVD) mortality rates than the general population. Whether a deficiency in the level of awareness, a prerequisite for change, exists that contributes to this socioeconomic divide has not been well established. OBJECTIVES: To address CVD risk by assessing the knowledge of CVD risk factors of an inner-city population and comparing it with that of the general population by establishing determinants of CVD knowledge and identifying potential barriers to CVD risk factor reduction in the inner city. METHODS: Cross-sectional survey of 136 consecutive patients 40 years of age and older attending an inner-city community health centre. The comparison group consisted of 807 age-matched respondents from the Canadian Heart Health Study, a random sample survey of the general adult Canadian population. Outcome measures included CVD risk factor knowledge, CVD risk factor prevalence and barriers to reducing CVD risk. RESULTS: There was no significant difference between inner-city respondent ability to name five of the seven CVD risk factors compared with the general population. Two CVD risk factors were more readily recalled by the inner-city group (lack of exercise, P<0.001; heredity, P=0.003). The average number of risk factors named by an individual from the inner city was significantly higher than the general population (3.1 versus 2.6; P<0.001). Among the inner-city respondents, socioeconomic factors, including higher education level (OR 5.224; P<0.001) and being married (OR 3.651; P=0.008), were independently related to good CVD knowledge; high CVD risk was not related. Lack of motivation (57%), lack of time (34%) and lack of money (30%) were commonly reported as barriers to addressing CVD risk. CONCLUSIONS: Elevated CVD risk in the inner city may not be attributable to a deficiency in the level of awareness. However, the relationship between socioeconomic status and knowledge is maintained within the lowest social class tier. The identification of barriers linked to inner-city life has implications for prevention of CVD in the inner city; results suggest that interventions that combine health education with motivational approaches, while necessary, may not be sufficient.


Subject(s)
Cardiovascular Diseases/prevention & control , Health Knowledge, Attitudes, Practice , Urban Population , Age Factors , Cardiovascular Diseases/etiology , Case-Control Studies , Cross-Sectional Studies , Educational Status , Exercise , Female , Health Promotion , Humans , Income , Male , Marital Status , Middle Aged , Motivation , Multivariate Analysis , Ontario , Risk Factors , Social Class , Surveys and Questionnaires , Time Factors , Urban Health
4.
J Pers Disord ; 21(1): 72-86, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17373891

ABSTRACT

This study employed an Experience Sampling Methodology (ESM) to test whether various elements of affective instability can predict future suicide ideation in patients with borderline personality disorder (BPD) and a history of recurrent suicidal behavior. Eighty-two individuals with BPD and a history of recurrent suicidal behavior were followed prospectively for one month during which time they recorded their current mood states, 6 times daily over three weeks. Accounting for a set of robust suicide risk factors in multiple regression analyses, only negative mood intensity was significantly related to intensity of self-reported suicide ideation and to number of suicidal behaviors over the past year. Other elements of affective instability examined (e.g., mood amplitude, dyscontrol, and reactivity) were not associated with future suicide ideation or with recent suicidal behavior. Affective instability in patients with BPD is highly variable from one individual to another and is characterized by high levels of intense negative mood. These negative mood states, versus other aspects of mood variability, seem to be more closely tied to the occurrence of suicidal ideation and behavior.


Subject(s)
Affect , Borderline Personality Disorder/psychology , Suicide/psychology , Adult , Aged , Anxiety , Female , Humans , Male , Middle Aged , Prospective Studies , Regression Analysis , Reproducibility of Results , Risk Assessment , Suicide, Attempted/psychology
5.
Am Heart J ; 152(2): 277-84, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16875908

ABSTRACT

BACKGROUND: Prior research suggests that patients may be entered into clinical trials with different electrocardiographic (ECG) findings than specified by study protocol criteria; the extent and impact of this variability in a large-scale trial have not been previously described. METHODS: We evaluated the relationship between case report form (CRF) categorization of the admission ECG and a Core Laboratory and subsequent outcome in a retrospective analysis of a trial of patients with acute ischemia and a broad spectrum of ECG changes (the GUSTO-IIb trial). RESULTS: In 11,037 patients with CRF information and an interpretable ECG, there was agreement in 89.1% of ST-elevation and 81.9% of non-ST-elevation cases. Among patients designated as having no ST elevation on the CRF, 1-year mortality rates were significantly higher in the subgroup of patients with Core Laboratory-determined ST elevation as compared with those where both the CRF and Core Laboratory classification were in agreement (8.8% vs 6.8%, P = .0093). Among patients designated as having ST elevation by the CRF, 1-year mortality rates were similar in both the subgroup of patients with and without Core Laboratory agreement (7.7% vs 8.2%, P = .72). CONCLUSIONS: These findings have important implications for clinicians in routine practice because even a simple evaluation (presence or absence of ST elevation) on the admission ECG was often discordant and was associated with adverse clinical outcome.


Subject(s)
Angina, Unstable/mortality , Electrocardiography , Myocardial Infarction/mortality , Aged , Female , Hospitalization , Humans , Male , Middle Aged , Multivariate Analysis , Prognosis , Randomized Controlled Trials as Topic , Retrospective Studies , Syndrome
6.
Am J Respir Crit Care Med ; 174(5): 538-44, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-16763220

ABSTRACT

RATIONALE: Little is known about the long-term outcomes and costs of survivors of acute respiratory distress syndrome (ARDS). OBJECTIVES: To describe functional and quality of life outcomes, health care use, and costs of survivors of ARDS 2 yr after intensive care unit (ICU) discharge. METHODS: We recruited a cohort of ARDS survivors from four academic tertiary care ICUs in Toronto, Canada, and prospectively monitored them from ICU admission to 2 yr after ICU discharge. MEASUREMENTS: Clinical and functional outcomes, health care use, and direct medical costs. RESULTS: Eighty-five percent of patients with ARDS discharged from the ICU survived to 2 yr; overall 2-yr mortality was 49%. At 2 yr, survivors continued to have exercise limitation although 65% had returned to work. There was no statistically significant improvement in health-related quality of life as measured by Short-Form General Health Survey between 1 and 2 yr, although there was a trend toward better physical role at 2 yr (p = 0.0586). Apart from emotional role and mental health, all other domains remained below that of the normal population. From ICU admission to 2 yr after ICU discharge, the largest portion of health care costs for a survivor of ARDS was the initial hospital stay, with ICU costs accounting for 76% of these costs. After the initial hospital stay, health care costs were related to hospital readmissions and inpatient rehabilitation. CONCLUSIONS: Survivors of ARDS continued to have functional impairment and compromised health-related quality of life 2 yr after discharge from the ICU. Health care use and costs after the initial hospitalization were driven by hospital readmissions and inpatient rehabilitation.


Subject(s)
Health Care Costs , Health Services/economics , Health Services/statistics & numerical data , Quality of Life , Respiratory Distress Syndrome/economics , Respiratory Distress Syndrome/therapy , Adult , Cohort Studies , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Recovery of Function/physiology , Respiratory Distress Syndrome/physiopathology , Respiratory Function Tests , Time Factors
7.
J Am Coll Cardiol ; 47(2): 354-61, 2006 Jan 17.
Article in English | MEDLINE | ID: mdl-16412860

ABSTRACT

OBJECTIVES: The purpose of this study was to determine the prevalence of thiamin deficiency (TD) in a cross section of hospitalized congestive heart failure (CHF) patients and to investigate factors that contribute to its development. BACKGROUND: Thiamin deficiency manifests as symptoms of CHF and, therefore, may worsen existing heart failure. Congestive heart failure patients may be at increased risk for TD as a result of diuretic-induced urine thiamin excretion, disease severity, malnutrition, and advanced age. METHODS: Erythrocyte thiamin pyrophosphate concentrations, using high-performance liquid chromatography, were measured in 100 CHF patients and compared to 50 control subjects. Variables including diuretics (type and dose), left ventricle dysfunction, New York Heart Association functional classification, creatinine clearance, thiamin intake (diet and supplements), malnutrition, appetite ratings, and age were related to TD using univariate statistics and multiple logistic regression analysis. RESULTS: Thiamin deficiency was more prevalent in CHF patients (33%) compared to control subjects (12%) (p = 0.007). Thiamin deficiency was related to urine thiamin loss (p = 0.03), non-use of thiamin-containing supplements (p = 0.06), and preserved renal function (p = 0.05). Increased urinary thiamin loss (mug/g creatinine) was found to be the only significant positive predictor of thiamin status on multiple logistic regression analysis (p = 0.03). CONCLUSIONS: One-third of hospitalized CHF patients were TD. In contrast to previous studies, increased urinary losses of thiamin were predictive of improved thiamin status. Thiamin supplementation may be protective against TD in the clinical setting. Future studies are warranted to determine if thiamin supplementation improves thiamin status and disease severity in CHF patients.


Subject(s)
Heart Failure/epidemiology , Thiamine Deficiency/epidemiology , Aged , Comorbidity , Cross-Sectional Studies , Erythrocytes/metabolism , Female , Hospitalization , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Ventricular Dysfunction, Left/epidemiology
8.
Crisis ; 26(4): 160-9, 2005.
Article in English | MEDLINE | ID: mdl-16485841

ABSTRACT

Assertive community treatment appears to have limited impact on the risk of suicide in persons with severe and persistent mental illness (SPMI). This exploratory prospective study attempts to understand this observation by studying the contribution of suicidality to the occurrence of crisis events in patients with SPMI. Specifically, an observer-rated measure of the need for hospitalization, the Crisis Triage Rating Scale, was completed at baseline, crisis occurrence, and resolution to determine how much the level of suicidality contributed to the deemed level of crisis. Second, observer-ratings of suicidal ideation, the Modified Scale for Suicide Ideation, and psychopathology and suicidality, Brief Psychiatric Rating Scale, were measured at baseline, crisis occurrence, and resolution. A self-report measure of distress, the Symptom Distress Scale, was completed at baseline, crisis occurrence, and resolution. Finally, the patients' crisis experiences were recorded qualitatively to compare with quantitative measures of suicidality. Almost 40% of the subjects experienced crisis events and more than a quarter of these events were judged to be severe enough to warrant the need for hospitalization. Our findings suggest that elevation of psychiatric symptoms is a major contributor to the crisis occurrences of individuals with SPMI; although the risk of suicide may have to be conceived as somewhat separate from crisis occurrence.


Subject(s)
Mental Disorders/psychology , Suicide/psychology , Adult , Aged , Canada , Case Management , Crisis Intervention , Female , Humans , Male , Middle Aged , Prospective Studies , Psychiatric Status Rating Scales , Risk , Suicide Prevention
9.
Cardiovasc Radiat Med ; 5(2): 59-63, 2004.
Article in English | MEDLINE | ID: mdl-15464941

ABSTRACT

BACKGROUND: Percutaneous coronary interventions (PCIs) are often complicated by postprocedural myocardial necrosis as manifested by elevated cardiac markers. PURPOSE: To assess the incidence and risk factors of elevated troponin-I (TnI) after PCI. METHODS AND RESULTS: We performed a retrospective analysis on 522 PCI cases over a 1-year period at a single center. An elevated postprocedural TnI (>1.0 ng/ml) occurred in 213 patients (40.8%). Overall, glycoprotein (GP) IIb/IIIa inhibitors were used in 52% of cases. Baseline clinical characteristics were similar between the positive and the negative TnI groups. A univariate analysis revealed that patients with elevated TnI post-PCI had significantly more multivessel (28% vs. 15%, P = .001) and multilesion interventions (44% vs. 27%, P<.0001). The lesions were longer, more often angulated and involving bifurcations, and more complex in the TnI-positive group. Stent use and number of stents was higher in the TnI-positive group, and longer inflation times (>30 s) or higher inflation pressures (>14 atm) were used more often in the TnI-positive group. GP IIb/IIIa inhibitor use was higher in the TnI-positive group (61% vs. 45%, P = .0007). After multivariable analysis, independent predictors of elevated TnI after PCI included multilesion intervention, lesion length, lesion angulation, and GP IIb/IIIa inhibitor use. CONCLUSION: TnI is elevated in approximately 40% of cases after PCI. TnI is more likely to be elevated after intervention on multiple lesions, angulated or long lesions.


Subject(s)
Angioplasty, Balloon, Coronary/adverse effects , Heart Diseases/epidemiology , Troponin I/blood , Aged , Female , Humans , Incidence , Male , Middle Aged , Multivariate Analysis , Necrosis/epidemiology , Necrosis/etiology , Platelet Aggregation Inhibitors/administration & dosage , Platelet Glycoprotein GPIIb-IIIa Complex/antagonists & inhibitors , Predictive Value of Tests , Retrospective Studies , Risk Factors , Stents/statistics & numerical data
10.
Anesth Analg ; 99(2): 528-35, table of contents, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15271734

ABSTRACT

Transfusion of anemic patients with hemoglobin-based oxygen carriers (HBOCs) may improve cerebral oxygen delivery. Conversely, cerebral vasoconstriction, associated with HBOC transfusion, could limit optimal cerebral tissue oxygenation. We hypothesized that hemodilution with a HBOC would maintain cerebral tissue oxygenation, despite the occurrence of cerebral vasoconstriction. Isoflurane-anesthetized rats (100% oxygen) underwent direct measurement of mean arterial blood pressure (MAP), caudate tissue oxygen tension (P(Br)o(2)), and regional cortical cerebral blood flow (rCBF) before and after 50% of the estimated blood volume (30 mL/kg) was exchanged with either an HBOC (hemoglobin raffimer; Hemolink) or pentastarch (n = 6). Hemodilution with hemoglobin raffimer caused a transient increase in P(Br)o(2) from 24.9 +/- 13.3 mm Hg to 32.2 +/- 19.1 mm Hg (P < 0.05), a sustained increase in MAP, and no change in rCBF. Arterial blood oxygen content was maintained despite an increase in methemoglobin and reduced oxygen saturation. Hemodilution with pentastarch caused a transient increase in MAP, no change in P(Br)o(2), and a sustained increase in rCBF (P < 0.05), whereas the hemoglobin concentration and oxygen content were significantly reduced. Hemodilution with hemoglobin raffimer augmented P(Br)o(2) and prevented the increase in rCBF observed after similar hemodilution with pentastarch. These data suggest that transfusion with hemoglobin raffimer may help to maintain cerebral oxygenation during severe anemia.


Subject(s)
Blood Substitutes/pharmacology , Brain Chemistry/drug effects , Hemodilution , Oxygen Consumption/drug effects , Animals , Blood Gas Analysis , Cerebrovascular Circulation/drug effects , Hydroxyethyl Starch Derivatives/pharmacology , Laser-Doppler Flowmetry , Microelectrodes , Phenylephrine/pharmacology , Plasma Substitutes/pharmacology , Polarography , Rats , Vasoconstrictor Agents/pharmacology
11.
Heart Rhythm ; 1(5): 540-7, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15851216

ABSTRACT

OBJECTIVES: The purpose of this study was to compare rate-only detection to enhanced detection in a dual-chamber implantable cardioverter-defibrillator (ICD), to discriminate ventricular tachycardia from supraventricular tachycardia. BACKGROUND: ICDs are highly effective in treating ventricular tachycardia (VT) or ventricular fibrillation (VF). However, they frequently deliver inappropriate therapy during supraventricular tachycardia (SVT). METHODS: We conducted a randomized clinical trial of detection enhancements in a dual-chamber ICD compared to control (rate-only) detection to discriminate VT from SVT. Detection enhancements included a specific standardized protocol identical for all patients for programming rate stability, sudden onset, atrial-to-ventricular relationship (sudden onset = 9% and rate stability = 10 ms; V > A "on"), and "sustained rate duration" (3 minutes). The primary endpoint was the time to first inappropriate therapy classified by a blinded events committee. RESULTS: One hundred forty-nine patients had a history of sustained VT or VF. Mean age (+/- SD) was 60 +/- 13 years; 83% were male, and mean ejection fraction was 35 +/- 15%. Control (n = 70) and "enhanced" (n = 79) groups did not differ with regard to age, sex, ejection fraction, or primary arrhythmia. The proportion of patients free of inappropriate therapy over time was significantly higher in the enhanced versus the control group (hazard ratio = 0.47, P = .011). High-energy shocks were reduced from 0.58 +/- 4.23 shocks/patient/month in the control group to 0.04 +/- 0.15 shocks/patient/month in the enhanced group (P = .0425). No patient programmed per protocol failed to receive therapy for VT detected by the ICD (422 VT episodes). CONCLUSIONS: Standardized programming in a dual-chamber ICD leads to a significant and clinically important reduction in inappropriate therapies compared to rate-only detection and does not compromise safety with respect to appropriate treatment of VT.


Subject(s)
Defibrillators, Implantable , Tachycardia, Supraventricular/diagnosis , Tachycardia, Supraventricular/therapy , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/therapy , Age Factors , Diagnosis, Differential , Equipment Design , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Multivariate Analysis
12.
Can J Anaesth ; 50(10): 1061-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14656789

ABSTRACT

PURPOSE: To test the hypotheses that deliberate elevation of PaCO(2) increases cerebral tissue oxygen tension (PBrO(2)) by augmenting PaO(2) and regional cerebral blood flow (rCBF). METHODS: Anesthetized rats were exposed to increasing levels of inspired oxygen (O(2)) or carbon dioxide (CO(2); 5%, 10% and 15%, n = 6). Mean arterial blood pressure (MAP), PBrO(2) and rCBF were measured continuously. Blood gas analysis and hemoglobin concentrations were determined for each change in inspired gas concentration. Data are presented as mean +/- standard deviation with P < 0.05 taken to be significant. RESULTS: The PBrO(2) increased in proportion to arterial oxygenation (PaO(2)) when the percentage of inspired O(2) was increased. Proportional increases in PaCO(2) (48.7 +/- 4.9, 72.3 +/- 6.0 and 95.3 +/- 15.4 mmHg), PaO(2) (172.2 +/- 33.1, 191.7 +/- 42.5 and 216.0 +/- 41.8 mmHg), and PBrO(2) (29.1 +/- 9.2, 49.4 +/- 19.5 and 60.5 +/- 23.0 mmHg) were observed when inspired CO(2) concentrations were increased from 0% to 5%, 10% and 15%, respectively, while arterial pH decreased (P < 0.05 for each). Exposure to CO(2) increased rCBF from 1.04 +/- 0.67 to a peak value of 1.49 +/- 0.45 (P < 0.05). Following removal of exogenous CO(2), arterial blood gas values returned to baseline while rCBF and PBrO(2) remained elevated for over 30 min. The hypercapnia induced increase in PBrO(2) was threefold higher than that resulting from a comparable increase in PaO(2) achieved by increasing the inspired O(2) concentration (34.9 +/- 14.5 vs 11.4 +/- 5.0 mmHg, P < 0.05). CONCLUSION: These data support the hypothesis that the combined effect of increased CBF, PaO(2) and reduced pH collectively contribute to augmenting cerebral PBrO(2) during hypercapnia.


Subject(s)
Brain/metabolism , Cerebrovascular Circulation/physiology , Hypercapnia/metabolism , Oxygen Consumption/physiology , Animals , Blood Gas Analysis , Male , Models, Animal , Rats , Rats, Sprague-Dawley
13.
N Engl J Med ; 348(8): 683-93, 2003 Feb 20.
Article in English | MEDLINE | ID: mdl-12594312

ABSTRACT

BACKGROUND: As more patients survive the acute respiratory distress syndrome, an understanding of the long-term outcomes of this condition is needed. METHODS: We evaluated 109 survivors of the acute respiratory distress syndrome 3, 6, and 12 months after discharge from the intensive care unit. At each visit, patients were interviewed and underwent a physical examination, pulmonary-function testing, a six-minute-walk test, and a quality-of-life evaluation. RESULTS: Patients who survived the acute respiratory distress syndrome were young (median age, 45 years) and severely ill (median Acute Physiology, Age, and Chronic Health Evaluation score, 23) and had a long stay in the intensive care unit (median, 25 days). Patients had lost 18 percent of their base-line body weight by the time they were discharged from the intensive care unit and stated that muscle weakness and fatigue were the reasons for their functional limitation. Lung volume and spirometric measurements were normal by 6 months, but carbon monoxide diffusion capacity remained low throughout the 12-month follow-up. No patients required supplemental oxygen at 12 months, but 6 percent of patients had arterial oxygen saturation values below 88 percent during exercise. The median score for the physical role domain of the Medical Outcomes Study 36-item Short-Form General Health Survey (a health-related quality-of-life measure) increased from 0 at 3 months to 25 at 12 months (score in the normal population, 84). The distance walked in six minutes increased from a median of 281 m at 3 months to 422 m at 12 months; all values were lower than predicted. The absence of systemic corticosteroid treatment, the absence of illness acquired during the intensive care unit stay, and rapid resolution of lung injury and multiorgan dysfunction were associated with better functional status during the one-year follow-up. CONCLUSIONS: Survivors of the acute respiratory distress syndrome have persistent functional disability one year after discharge from the intensive care unit. Most patients have extrapulmonary conditions, with muscle wasting and weakness being most prominent.


Subject(s)
Analysis of Variance , Muscle Weakness/etiology , Respiratory Distress Syndrome/complications , APACHE , Adult , Age Factors , Aged , Alopecia/etiology , Fatigue/etiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Quality of Life , Respiration , Respiratory Distress Syndrome/classification , Respiratory Distress Syndrome/physiopathology , Respiratory Function Tests , Survivors , Walking
14.
J Appl Physiol (1985) ; 94(5): 2058-67, 2003 May.
Article in English | MEDLINE | ID: mdl-12533500

ABSTRACT

Severe hemodilutional anemia may reduce cerebral oxygen delivery, resulting in cerebral tissue hypoxia. Increased nitric oxide synthase (NOS) expression has been identified following cerebral hypoxia and may contribute to the compensatory increase in cerebral blood flow (CBF) observed after hypoxia and anemia. However, changes in cerebral NOS gene expression have not been reported after acute anemia. This study tests the hypothesis that acute hemodilutional anemia causes cerebral tissue hypoxia, triggering changes in cerebral NOS gene expression. Anesthetized rats underwent hemodilution when 30 ml/kg of blood were exchanged with pentastarch, resulting in a final hemoglobin concentration of 51.0 +/- 1.2 g/l (n = 7 rats). Caudate tissue oxygen tension (Pbr(O(2))) decreased transiently from 17.3 +/- 4.1 to 14.4 +/- 4.1 Torr (P < 0.05), before returning to baseline after approximately 20 min. An increase in CBF may have contributed to restoring Pbr(O(2)) by improving cerebral tissue oxygen delivery. An increase in neuronal NOS (nNOS) mRNA was detected by RT-PCR in the cerebral cortex of anemic rats after 3 h (P < 0.05, n = 5). A similar response was observed after exposure to hypoxia. By contrast, no increases in mRNA for endothelial NOS or interleukin-1beta were observed after anemia or hypoxia. Hemodilutional anemia caused an acute reduction in Pbr(O(2)) and an increase in cerebral cortical nNOS mRNA, supporting a role for nNOS in the physiological response to acute anemia.


Subject(s)
Anemia/enzymology , Anemia/etiology , Brain Chemistry/genetics , Gene Expression Regulation, Enzymologic/genetics , Hemodilution/adverse effects , Nitric Oxide Synthase/biosynthesis , Animals , Blood Gas Analysis , Calibration , Cerebrovascular Circulation/physiology , Electrophoresis, Agar Gel , Hemoglobins/metabolism , Hypoxia/enzymology , Laser-Doppler Flowmetry , Microelectrodes , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type I , Nitric Oxide Synthase Type III , Polarography , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Up-Regulation
15.
Am Heart J ; 144(2): 243-50, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12177641

ABSTRACT

BACKGROUND: Data on non-Q myocardial infarctions (MI) are derived primarily from prethrombolytic era studies. Previous trials demonstrated different development rates and none reported on clinical outcomes. METHODS: Our goal was to determine the incidence and prognosis of non-Q-wave MI among patients with ST-segment elevation receiving thrombolysis. A retrospective analysis of 5 randomized controlled trials was made. The main outcome measures included rates of (1) transformation of ST-segment elevation to Q- and non-Q-wave MI and (2) inhospital and 1-year mortality and reinfarction among patients who subsequently develop a Q or non-Q MI postthrombolysis as compared to controls. RESULTS: Non-Q wave development was greater among patients receiving thrombolysis versus placebo/control (3.1% absolute difference, 95% CI 1.2%-5.0%). Among patients receiving thrombolysis, those who developed a non-Q MI experienced significantly lower inhospital and 1-year mortality (absolute differences -3.8% [95% CI -5.2% to -2.4%] and -6.4% [95% CI -9.9% to -3.0%], respectively) and reinfarction (absolute differences -2.9% [95% CI -4.3% to -1.6%] and -3.5% [95% CI -6.1% to -0.9%], respectively) rates, compared with those who evolved a Q MI. Inhospital and 1-year mortality was also significantly lower when compared to placebo/control patients who developed a non-Q MI (absolute differences 4.6% [95% CI -8.2% to -1.1%] and -7.5% [95% CI -12.5% to -2.5%], respectively). CONCLUSIONS: Patients receiving thrombolysis more often develop a non-Q-wave MI and have a better prognosis than either those who develop a Q MI postthrombolysis or a non-Q MI after standard medical therapy.


Subject(s)
Myocardial Infarction/epidemiology , Electrocardiography , Hospital Mortality , Humans , Incidence , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Myocardial Reperfusion , Observer Variation , Prognosis , Randomized Controlled Trials as Topic , Recurrence , Retrospective Studies , Survival Rate , Thrombolytic Therapy/statistics & numerical data , Treatment Outcome
16.
Am Heart J ; 143(6): 1092-100, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12075268

ABSTRACT

BACKGROUND: Congestive heart failure depletes the myocardium of carnitine, coenzyme Q10 (CoQ10), and taurine--substances known to influence mitochondrial function and cell calcium. We hypothesized that feeding patients a nutritional supplement that contained carnitine, CoQ10, and taurine would result in higher myocardial levels of these nutrients and improve left ventricular function. METHODS: Forty-one patients who underwent aortocoronary artery bypass with an ejection fraction < or =40% at referral were randomly assigned to a double-blind trial of supplement or placebo. Radionuclide ventriculography was performed at randomization and before surgery. Surgical myocardial biopsies, adjusted for protein content, were analyzed for carnitine, CoQ10, and taurine levels. RESULTS: The groups were well matched. Minor exceptions were supplement group versus placebo group for digoxin use (7 vs 0, respectively; P =.009) and age (62 +/- 11 years vs 69 +/- 5 years, respectively; P =.04). There were significantly higher levels in the treated group compared with the placebo group for myocardial levels of CoQ10 (138.17 +/- 39.87 nmol/g wet weight and 56.67 +/- 23.08 nmol/g wet weight; P =.0006), taurine (13.12 +/- 4.00 micromol/g wet weight and 7.91 +/- 2.81 micromol/g wet weight; P =.003), and carnitine (1735.4 +/- 798.5 nmol/g wet weight and 1237.6 +/- 343.1 nmol/g wet weight; P =.06). The left ventricular end-diastolic volume fell by -7.5 +/- 21.7 mL in the supplement group and increased by 10.0 +/- 19.8 mL in the placebo group (P =.037). CONCLUSIONS: Supplementation results in higher myocardial CoQ10, taurine, and carnitine levels and is associated with a reduction in left ventricular end-diastolic volume in patients with left ventricular dysfunction before revascularization. Because the risk of death for surgical revascularization is related to preoperative left ventricular end-diastolic volume, supplementation could improve outcomes.


Subject(s)
Carnitine/metabolism , Dietary Supplements , Heart Failure/metabolism , Myocardium/metabolism , Taurine/metabolism , Ubiquinone/analogs & derivatives , Ubiquinone/metabolism , Ventricular Dysfunction, Left/therapy , Aged , Carnitine/administration & dosage , Carnitine/analysis , Coenzymes , Double-Blind Method , Female , Humans , Male , Middle Aged , Radionuclide Ventriculography/methods , Taurine/administration & dosage , Taurine/analysis , Ubiquinone/administration & dosage , Ubiquinone/analysis , Ventricular Dysfunction, Left/metabolism
17.
N Engl J Med ; 346(12): 884-90, 2002 Mar 21.
Article in English | MEDLINE | ID: mdl-11907287

ABSTRACT

BACKGROUND: Lidocaine has been the initial antiarrhythmic drug treatment recommended for patients with ventricular fibrillation that is resistant to conversion by defibrillator shocks. We performed a randomized trial comparing intravenous lidocaine with intravenous amiodarone as an adjunct to defibrillation in victims of out-of-hospital cardiac arrest. METHODS: Patients were enrolled if they had out-of-hospital ventricular fibrillation resistant to three shocks, intravenous epinephrine, and a further shock; or if they had recurrent ventricular fibrillation after initially successful defibrillation. They were randomly assigned in a double-blind manner to receive intravenous amiodarone plus lidocaine placebo or intravenous lidocaine plus amiodarone placebo. The primary end point was the proportion of patients who survived to be admitted to the hospital. RESULTS: In total, 347 patients (mean [+/-SD] age, 67+/-14 years) were enrolled. The mean interval between the time at which paramedics were dispatched to the scene of the cardiac arrest and the time of their arrival was 7+/-3 minutes, and the mean interval from dispatch to drug administration was 25+/-8 minutes. After treatment with amiodarone, 22.8 percent of 180 patients survived to hospital admission, as compared with 12.0 percent of 167 patients treated with lidocaine (P=0.009; odds ratio, 2.17; 95 percent confidence interval, 1.21 to 3.83). Among patients for whom the time from dispatch to the administration of the drug was equal to or less than the median time (24 minutes), 27.7 percent of those given amiodarone and 15.3 percent of those given lidocaine survived to hospital admission (P=0.05). CONCLUSIONS: As compared with lidocaine, amiodarone leads to substantially higher rates of survival to hospital admission in patients with shock-resistant out-of-hospital ventricular fibrillation.


Subject(s)
Amiodarone/therapeutic use , Anti-Arrhythmia Agents/therapeutic use , Lidocaine/therapeutic use , Ventricular Fibrillation/drug therapy , Aged , Combined Modality Therapy , Double-Blind Method , Electric Countershock , Emergency Medical Services , Female , Heart Arrest/drug therapy , Heart Arrest/therapy , Hospitalization , Humans , Infusions, Intravenous , Logistic Models , Male , Middle Aged , Recurrence , Survival Rate , Time Factors , Ventricular Fibrillation/mortality , Ventricular Fibrillation/therapy
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