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61.
Intensivists have the potential to maintain vital signs almost indefinitely, but not necessarily the potential to make moribund patients whole. Current ethical and legal mandates push patient autonomy to the forefront of care plans. When patients are incapable of expressing their preferences, surrogates are given proxy. It is unclear how these preferences extend to the very brink of inevitable death. Some say that patients should have the opportunity and authority to direct their death spiral. Others say it would be impossible for them to do so because an inevitable death spiral cannot be effectively palliated. Humane principles dictate they be spared the unrelenting discomfort surrounding death. The present case examines such a patient and the issues surrounding a unique end-of-life decision.  相似文献   
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63.
Journal of Cross-Cultural Gerontology - This study aimed to investigate the validity and factor structure of the Self-Assessed Wisdom Scale (SAWS; Webster in J Adult Dev 10:13–22, 2003) in an...  相似文献   
64.
BACKGROUND: Vascular inflammation generating oxidized metabolites at the site of balloon angioplasty is believed to play a major role in the process of vessel restenosis. Glutathione, the most potent endogenous antioxidant, may have protective effects after angioplasty by suppressing local inflammatory response. The aim of the study was to test the hypothesis that oral administration of N-acetyl-cysteine (NAC, a precursor of glutathione) reduces restenosis in an animal model of vascular injury. METHODS: In New Zealand white rabbits, an atherosclerotic lesion was introduced to both iliac arteries by air denudation of the endothelium while feeding the animals a high-cholesterol diet. After 4 weeks, all animals underwent balloon angioplasty of the endothelial injury site and half of the group was started on 150 mg/kg NAC per day. Quantitative angiography was performed prior to the angioplasty and at the final procedure 3 weeks later. Glutathione levels were determined in all animals at the beginning and the end of the study. RESULTS: Although not statistically significant, plasma glutathione level increased in the NAC group from 32.4+/-4.4 to 39.7+/-11.6 micromol/l, while it decreased from 30.6+/-13.4 to 28.3+/-11.5 micromol/l in the control group. During the study period, 6 vessels occluded leaving 14 vessels for analysis. Quantitative angiographic analyses prior to angioplasty and at follow-up showed no significant difference with respect to stenosis progression between the groups. Measurement of neointima formation by histology showed also no significant difference between the groups (0.175+/-0.040 mm(2) vs. 0.123+/-0.075 mm(2)), neither did intimal macrophage count as a marker for local inflammatory response. CONCLUSIONS: Despite an increase in plasma glutathione level in the NAC-treated group, there was no reduction in lesion progression after balloon angioplasty. Therefore, NAC does not seem to prevent restenosis after vascular intervention in this animal model.  相似文献   
65.
66.
Freshwater bodies and, consequently, drinking water treatment plants (DWTPs) sources are increasingly facing toxic cyanobacterial blooms. Even though conventional treatment processes including coagulation, flocculation, sedimentation, and filtration can control cyanobacteria and cell-bound cyanotoxins, these processes may encounter challenges such as inefficient removal of dissolved metabolites and cyanobacterial cell breakthrough. Furthermore, conventional treatment processes may lead to the accumulation of cyanobacteria cells and cyanotoxins in sludge. Pre-oxidation can enhance coagulation efficiency as it provides the first barrier against cyanobacteria and cyanotoxins and it decreases cell accumulation in DWTP sludge. This critical review aims to: (i) evaluate the state of the science of cyanobacteria and cyanotoxin management throughout DWTPs, as well as their associated sludge, and (ii) develop a decision framework to manage cyanobacteria and cyanotoxins in DWTPs and sludge. The review identified that lab-cultured-based pre-oxidation studies may not represent the real bloom pre-oxidation efficacy. Moreover, the application of a common exposure unit CT (residual concentration × contact time) provides a proper understanding of cyanobacteria pre-oxidation efficiency. Recently, reported challenges on cyanobacterial survival and growth in sludge alongside the cell lysis and cyanotoxin release raised health and technical concerns with regards to sludge storage and sludge supernatant recycling to the head of DWTPs. According to the review, oxidation has not been identified as a feasible option to handle cyanobacterial-laden sludge due to low cell and cyanotoxin removal efficacy. Based on the reviewed literature, a decision framework is proposed to manage cyanobacteria and cyanotoxins and their associated sludge in DWTPs.  相似文献   
67.

Objective

The purpose of the present study is to compare efficacy and safety of buccal midazolam with intravenous diazepam in control of seizures in Iranian children.

Methods

This is a randomized clinical trial. 92 patients with acute seizures, ranging from 6 months to 14 years were randomly assigned to receive either buccal midazolam (32 cases) or intravenous diazepam (60 cases) at the emergency department of a children''s hospital. The primary outcome of this study was cessation of visible seizure activity within 5 minutes from administration of the first dosage. The second dosage was used in case the seizure remained uncontrolled 5 minutes after the first one.

Findings

In the midazolam group, 22 (68.8%) patients were relieved from seizures in 10 minutes. Meanwhile, diazepam controlled the episodes of 42 (70%) patients within 10 minutes. The difference was, however, not statistically significant (P=0.9). The mean time required to control the convulsive episodes after administration of medications was not statistically significant (P=0.09). No significant side effects were observed in either group. Nevertheless, the risk of respiratory failure in intravenous diazepam is greater than in buccal midazolam.

Conclusion

Buccal midazolam is as effective as and safer than intravenous diazepam in control of seizures.  相似文献   
68.

Background

Sepsis complication is a major cause of death in multiple trauma critically ill patients. Defensin (cysteine rich anti-microbial peptides), as an important component of immune system, might play an important role in this process. There is also rising data on immunological effects of N-acetyl-cysteine (NAC), a commonly used anti-oxidant in oxidative stress conditions and glutathione (GSH) deficiencies. The aim of the present study was to evaluate the potential beneficial effects of NAC administration on multiple trauma patients with sepsis.

Methods

In a prospective, randomized controlled study, 44 multiple trauma critically ill patients who were mechanically ventilated and met the criteria of sepsis and admitted to the intensive care unit (ICU) were randomized into two groups . Control group received all standard ICU therapies and NAC group received intravenous NAC 3 gr every 6 hours for 72 hours in addition to standard therapies. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores, length of ICU stay, ICU mortality were recorded. Levels of serum Immunoglobulin M (IgM), Human β-Defensin 2 (HβD2) and GSH were assessed at baseline and 24, 72, 120 hours after intervention.

Results

During a period of 13-month screening, 44 patients underwent randomization but 5 patients had to be excluded. 21 patients in NAC group and 18 patients in control group completed the study. For both groups the length of ICU stay, SOFA score and systemic oxygenation were similar. Mortality rate (40% vs. 22% respectively, p = 0.209) and ventilator days (Mean ± SD 19.82 ± 19.55 days vs. 13.82 ± 11.89 days respectively, p = 0.266) were slightly higher for NAC group. IgM and GSH levels were similar between two groups (p = 0.325, 0.125 respectively), HβD2 levels were higher for NAC group (at day 3).

Conclusion

High dose of NAC administration not only did not improve patients’ outcome, but also raised the risk of inflammation and was associated with increased serum creatinine.  相似文献   
69.

Background

Recently, several studies have been conducted to determine the optimal strategy for intra-operative fluid replacement therapy in renal transplantation surgery. Since infusion of sodium bicarbonate as a buffer seems to be safer than other buffer compounds (lactate, gluconate, acetate)that indirectly convert into it within the liver, We hypothesized tight control of metabolic acidosis by infusion of sodium bicarbonate may improve early post-operative renal function in renal transplant recipients.

Methods

120 patients were randomly divided into two equal groups. In group A, bicarbonate was infused intra-operatively according to Base Excess (BE) measurements to achieve the normal values of BE (−5 to +5 mEq/L). In group B, infusion of bicarbonate was allowed only in case of severe metabolic acidosis (BE ≤ −15 mEq/L or bicarbonate ≤ 10 mEq/L or PH ≤ 7.15). Minute ventilation was adjusted to keep PaCO2 within the normal range. Primary end-point was sampling of serum creatinine level in first, second, third and seventh post-operative days for statistical comparison between groups. Secondary objectives were comparison of cumulative urine volumes in the first 24 h of post-operative period and serum BUN levels which were obtained in first, second, third and seventh post-operative days.

Results

In group A, all of consecutive serum creatinine levels were significantly lower in comparison with group B. With regard to secondary outcomes, no significant difference between groups was observed.

Conclusion

Intra-operative tight control of metabolic acidosis by infusion of Sodium Bicarbonate in renal transplant recipients may improve early post-operative renal function.  相似文献   
70.
Background: The main objective of this study was to evaluate the prevalence of the obesity and the related risk factors in the north of Iran. Methods: This was a population-based cross-sectional study that enrolled 2495 subjects (1247 males and 1248 females) using stratified cluster sampling. Interviewers recorded the data using a multidimensional questionnaire including anthropometric indexes. Body mass index equal to or greater than 25 was considered as overweight and that of 30 and 40 as obese and pathologic obese respectively. SPSS 16.0 software was used for statistical data analysis. Results: Mean age of the subjects was 39.2 [95% CI: 38.6, 39.8] yr. Mean body mass index was 25.3 [95% CI: 25.0, 25.6] kg/m(2) for men and 27.5 [95% CI: 27.2, 27.9] kg/m2 for women. The prevalence rates of overweight, obesity and pathologic obesity were 29.9% (745/2495), 22.5% (561/2495) and 1.8% (44/2495) respectively. The prevalence of obesity was higher in urban residents than rural ones, 27.3% versus 18.9% respectively (P<0.001). The prevalence rates of obesity and pathologic obesity were much higher in women than men were, 30.3% versus 15.4% and 3.0% versus 0.6% respectively (P=0.001). The odds ratio estimate was 1.68 [95% CI: 1.40, 2.02] for urban area compared to rural area; 2.60 [95% CI: 2.14, 3.15] for females compared to males; 5.95 [95% CI: 3.54, 9.99] for married people compared to single people; 1.89 [95% CI: 1.44, 2.84] for age group of 55-65 years compared to age group of 15-24 years; 1.76 [95% CI: 1.17, 2.64] for illiterate people compared to those who had academic education; 1.98 [95% CI: 1.13, 2.49] for poor people compared to people with high economic level. Conclusion: The prevalence of obesity and overweight is very high in the north of Iran, hence is a signal of serious health problem, and should be the focus of special attention.  相似文献   
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