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41.
An electrical impedance-based noninvasive respiratory volume monitor (RVM) accurately reports minute volume, tidal volume and respiratory rate. Here we used the RVM to quantify the occurrence of and evaluate the ability of clinical factors to predict respiratory depression in the post-anesthesia care unit (PACU). RVM generated respiratory data were collected from spontaneously breathing patients following intraperitoneal surgeries under general anesthesia admitted to the PACU. Respiratory depression was defined as low minute ventilation episode (LMVe, <?40% predicted minute ventilation for at least 2 min). We evaluated for associations between clinical variables including minute ventilation prior to opioid administration and LMVe following the first PACU administration of opioid. Also assessed was a low respiratory rate (<?8 breaths per minute) as a proxy for LMVe. Of 107 patients, 38 (36%) had LMVe. Affected patients had greater intraoperative opioid dose, P?=?0.05. PACU opioids were administered to 45 (42.1%) subjects, of which 27 (25.2%) had LMVe (P?=?0.42) within 30 min following opioid. Pre-opioid minute ventilation <?70% of predicted normal value was associated with LMVe, P?<?0.01, (sensitivity?=?100%, specificity?=?81%).Low respiratory rate was a poor predictor of LMVe (sensitivity?=?11.8%). Other clinical variables (e.g., obstructive sleep apnea) were not found to be predictors of LMVe. Using RVM we identified that mild, clinically nondetectable, respiratory depression prior to opioid administration in the PACU was associated with the development of substantial subsequent respiratory depression during the PACU stay.  相似文献   
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43.

Context

Risk profiling of oncology patients based on their symptom experience assists clinicians to provide more personalized symptom management interventions. Recent findings suggest that oncology patients with distinct symptom profiles can be identified using a variety of analytic methods.

Objectives

The objective of this study was to evaluate the concordance between the number and types of subgroups of patients with distinct symptom profiles using latent class analysis and K-modes analysis.

Methods

Using data on the occurrence of 25 symptoms from the Memorial Symptom Assessment Scale, that 1329 patients completed prior to their next dose of chemotherapy (CTX), Cohen's kappa coefficient was used to evaluate for concordance between the two analytic methods. For both latent class analysis and K-modes, differences among the subgroups in demographic, clinical, and symptom characteristics, as well as quality of life outcomes were determined using parametric and nonparametric statistics.

Results

Using both analytic methods, four subgroups of patients with distinct symptom profiles were identified (i.e., all low, moderate physical and lower psychological, moderate physical and higher Psychological, and all high). The percent agreement between the two methods was 75.32%, which suggests a moderate level of agreement. In both analyses, patients in the all high group were significantly younger and had a higher comorbidity profile, worse Memorial Symptom Assessment Scale subscale scores, and poorer QOL outcomes.

Conclusion

Both analytic methods can be used to identify subgroups of oncology patients with distinct symptom profiles. Additional research is needed to determine which analytic methods and which dimension of the symptom experience provide the most sensitive and specific risk profiles.  相似文献   
44.
Unipolar and bipolar depressive episodes have a similar clinical presentation that suggests common dysfunction of the brain’s reward system. Here, we evaluated the relationship of both dimensional depression severity and diagnostic category to reward system function in both bipolar and unipolar depression. In total, 89 adults were included, including 27 with bipolar depression, 25 with unipolar depression, and 37 healthy comparison subjects. Subjects completed both a monetary reward task and a resting-state acquisition during 3T BOLD fMRI. Across disorders, depression severity was significantly associated with reduced activation for wins compared with losses in bilateral ventral striatum, anterior cingulate cortex, posterior cingulate cortex, and right anterior insula. Resting-state connectivity within this reward network was also diminished in proportion to depression severity, most notably connectivity strength in the left ventral striatum. In addition, there were categorical differences between patient groups: resting-state connectivity at multiple reward network nodes was higher in bipolar than in unipolar depression. Reduced reward system task activation and resting-state connectivity therefore appear to be a brain phenotype that is dimensionally related to depression severity in both bipolar and unipolar depression. In contrast, categorical differences in reward system resting connectivity between unipolar and bipolar depression may reflect differential risk of mania. Reward system dysfunction thus represents a common brain mechanism with relevance that spans categories of psychiatric diagnosis.  相似文献   
45.
Cardiovascular Drugs and Therapy - Obesity is associated with systemic insulin resistance and cardiac hypertrophy with fibrosis. Peroxisome proliferator-activated receptors (PPARs) regulate...  相似文献   
46.
47.
Mild renal impairment is an important risk factor for late cardiovascular complications. This substudy of the Lescol Intervention Prevention Study (LIPS) assessed the effect of fluvastatin on outcome of patients who had renal dysfunction and those who did not. Complete data for creatinine clearance calculation (Cockcroft-Gault formula) were available for 1,558 patients (92.9% of the LIPS population). Patients were randomized to fluvastatin or placebo after successful completion of a first percutaneous coronary intervention. Follow-up time was 3 to 4 years. The effect of baseline creatinine clearance on coronary atherosclerotic events (cardiac death, nonfatal myocardial infarction, and coronary reinterventions not related to restenosis) was evaluated. Baseline creatinine clearance (logarithmic transformation) was inversely associated with an incidence of adverse events among patients who received placebo (hazard ratio 0.99, 95% confidence interval 0.982 to 0.998, p = 0.01). However, no association was noted between creatinine clearance and the incidence of adverse events among patients who received fluvastatin (hazard ratio 1.0, 95% confidence interval 0.99 to 1.0, p = 0.63). No further deterioration in creatinine clearance was observed during follow-up, regardless of baseline renal function or allocated treatment. Occurrence of adverse events was not related to changes in renal function during follow-up. Fluvastatin therapy markedly decreased the risk of coronary atherosclerotic events after percutaneous intervention in patients who had lower values of creatinine clearance at baseline. The benefit of fluvastatin was unrelated to any effect on renal function.  相似文献   
48.
The prognostic value of a hypertensive blood pressure (BP) response is still unclear. Therefore, the prognostic value of a hypertensive BP response in patients during single-stage exercise testing for peripheral arterial disease (PAD) on long-term mortality and major adverse cerebrovascular and cardiac events (MACCEs) was investigated. In addition, effects of statin, beta-blocker, and aspirin use in patients with known or suspected PAD were studied. A total of 2,109 patients were enrolled in an observational prospective study from 1993 to 2005. Hypertensive BP response was defined as an increase in systolic BP >/=55 mm Hg (95(th) percentile within our population) after a single-stage treadmill exercise test. The outcome was obtained by using the civil registries, and a questionnaire about cardiac events was sent to all survivals. Hypertensive BP response was associated with increased risk of long-term mortality (hazard ratio [HR] 1.42, 95% confidence interval [CI] 1.12 to 1.80) and MACCEs (HR 1.47, 95% CI 1.09 to 1.97). After adjustments for clinical risk factors and propensity score, baseline statin use was associated with reduced risk of long-term mortality (HR 0.59, 95% CI 0.44 to 0.79), and statin, beta-blocker, and aspirin use were associated with reduced risk of MACCEs (HR 0.59, 95% CI 0.43 to 0.81; HR 0.75, 95% CI 0.60 to 0.95; HR 0.73, 95% CI, 0.57 to 0.92, respectively). In conclusion, hypertensive BP response at exercise in patients with known or suspected PAD is an important independent risk factor for all-cause long-term mortality and MACCEs, whereas statin, beta-blocker, and aspirin use were associated with an improved outcome.  相似文献   
49.
The role of uric acid as an independent marker of cardiovascular risk is unclear. Therefore, our aim was to assess the independent contribution of preoperative serum uric acid levels to the risk of 30-day and late mortality and major adverse cardiac event (MACE) in patients scheduled for open vascular surgery. In total, 936 patients (76% male, age 68 +/- 11 years) were enrolled. Hyperuricemia was defined as serum uric acid >0.42 mmol/l for men and >0.36 mmol/l for women, as defined by large epidemiological studies. Outcome measures were 30-day and late mortality and MACE (cardiac death or myocardial infarction). Multivariable logistic and Cox regression analysis were used, adjusting for age, gender, and all cardiac risk factors. Data are presented as odds ratios or hazard ratios, with 95% confidence intervals. Hyperuricemia was present in 299 patients (32%). The presence of hyperuricemia was associated with heart failure, chronic kidney disease, and the use of diuretics. Perioperatively, 46 patients (5%) died and 61 patients (7%) experienced a MACE. Mean follow-up was 3.7 years (range: 0 to 17 years). During follow-up, 282 patients (30%) died and 170 patients (18%) experienced a MACE. After adjustment for all clinical risk factors, the presence of hyperuricemia was not significantly associated with an increased risk of 30-day mortality or MACE, odds ratios of 1.5 (0.8 to 2.8) and 1.7 (0.9 to 3.0), respectively. However, the presence of hyperuricemia was associated with an increased risk of late mortality and MACE, with hazard ratios of 1.4 (1.1 to 1.7) and 1.7 (1.3 to 2.3), respectively. In conclusion, the presence of preoperative hyperuricemia in vascular patients is a significant predictor of late mortality and MACE.  相似文献   
50.
Clenbuterol is a β2‐agonist prescribed for asthmatic patients in some countries. Based on its anabolic and lipolytic effects observed in studies on rodents and in livestock destined for food production, clenbuterol is abused by bodybuilders and athletes seeking leanness. Urinary clenbuterol analysis is part of routine doping analysis. However, the collection of urine samples is time‐consuming and can be intimidating for athletes. Dried blood spot (DBS) appears attractive as an alternative matrix, but the detectability of clenbuterol in humans through DBS has not been investigated. This study evaluated if clenbuterol could be detected in DBS and urine collected from six healthy men after oral intake of 80 μg clenbuterol. The DBS and urine samples were collected at 0, 3, 8, 24, and 72 h post‐ingestion, with additional urine collections on days 7 and 10. Using LC–MS/MS, it was shown that clenbuterol could be detected in all DBS samples for 24 h post‐ingestion and with 50% sensitivity 3 days after ingestion. The DBS method was 100% specific. Evaluation of analyte stability showed that clenbuterol is stable in DBS for at least 365 days at room temperature when using desiccant and avoiding light exposure. In urine, clenbuterol was detectable for at least 7–10 days after ingestion. Urinary clenbuterol concentrations below 5 ng/mL were present in some subjects 24 h after administration. Collectively, these data indicate that DBS are suitable for routine doping control analysis of clenbuterol with a detection window of at least 3 days after oral administration of 80 μg.  相似文献   
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