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31.
OBJECTIVES:: To compare causes of death (CoDs) from two independent sources: National Basic Death File (NBDF) and deaths reported to the Spanish HIV Research cohort [Cohort de adultos con infección por VIH de la Red de Investigación en SIDA CoRIS)] and compare the two coding algorithms: International Classification of Diseases, 10th revision (ICD-10) and revised version of Coding Causes of Death in HIV (revised CoDe). METHODS:: Between 2004 and 2008, CoDs were obtained from the cohort records (free text, multiple causes) and also from NBDF (ICD-10). CoDs from CoRIS were coded according to ICD-10 and revised CoDe by a panel. Deaths were compared by 13 disease groups: HIV/AIDS, liver diseases, malignancies, infections, cardiovascular, blood disorders, pulmonary, central nervous system, drug use, external, suicide, other causes and ill defined. RESULTS:: There were 160 deaths. Concordance for the 13 groups was observed in 111 (69%) cases for the two sources and in 115 (72%) cases for the two coding algorithms. According to revised CoDe, the commonest CoDs were HIV/AIDS (53%), non-AIDS malignancies (11%) and liver related (9%), these percentages were similar, 57, 10 and 8%, respectively, for NBDF (coded as ICD-10). When using ICD-10 to code deaths in CoRIS, wherein HIV infection was known in everyone, the proportion of non-AIDS malignancies was 13%, liver-related accounted for 3%, while HIV/AIDS reached 70% due to liver-related, infections and ill-defined causes being coded as HIV/AIDS. CONCLUSION:: There is substantial variation in CoDs in HIV-infected persons according to sources and algorithms. ICD-10 in patients known to be HIV-positive overestimates HIV/AIDS-related deaths at the expense of underestimating liver-related diseases, infections and ill defined causes. CoDe seems as the best option for cohort studies.  相似文献   
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BACKGROUND: The purpose of this study was to define risk factors that predict 30-day morbidity and mortality after gastrectomy for cancer in Veterans Affairs (VA) Medical Centers. METHODS: The VA National Surgical Quality Improvement Program prospectively collected data on 708 patients undergoing gastrectomy for cancer in 123 participating VA medical centers from 1991 to 1998. Independent variables included 68 preoperative patient characteristics and 12 intraoperative variables; the dependent variables were 21 defined adverse outcomes and death. Predictive models for 30-day morbidity and mortality were constructed by using stepwise logistic regression analysis. RESULTS: The 30-day morbidity rate was 33.3% (236 of 708). The overall 30-day mortality rate was 7.6% (54 of 708). Significant positive predictors of morbidity (P <.05) included current pneumonia, American Society of Anesthesiologists class IV (threat to life), partially dependent functional status, dyspnea on minimal exertion, preoperative transfusion, extended operative time, and increasing age. Significant positive predictors of mortality (P <.05) included do not resuscitate status, prior stroke, intraoperative transfusion, preoperative weight loss, preoperative transfusion, and elevated preoperative alkaline phosphatase level. CONCLUSIONS: Risk factors predicting morbidity and mortality rates at VA hospitals after gastrectomy for gastric cancer are reported by using a prospectively collected, multi-institutional database. Assigning relative weights to factors associated with adverse outcomes may help improve patient care.  相似文献   
34.
In patients with head injury, endotracheal suctioning (ETS) is a potentially dangerous procedure, because it can increase intracranial pressure (ICP). The purpose of this prospective nonrandomized study was to evaluate the impact of ETS on intracranial dynamics in the acute phase of head injury. Seventeen patients with severe head injury (Glasgow Coma Score < or = 8, range 4-8), sedated and mechanically ventilated, were studied during the first week after trauma. Single-pass ETS maneuver (with a 16-French catheter, negative pressure of 100 mm Hg, and duration of less than 30 seconds) was performed 60 seconds after the FiO2 was increased to 100%. After ETS, FiO2 was maintained at 100% for another 30 seconds. Before and after ETS, arterial blood gases and jugular oxygen saturation (S(j)O2), ICP, and mean arterial pressure (MAP) were measured and cerebral perfusion pressure (CPP) was calculated. A total of 131 ETS episodes, which consisted of repeated assessment of each patient, were analyzed. Six patients in 20 cases coughed and/or moved during ETS because of inadequate sedation. After ETS, ICP increased from 20 +/- 12 to 22 +/- 13 mm Hg in well-sedated patients and from 15 +/- 9 to 28 +/- 9 mm Hg in patients who coughed and/or moved (mean change, 2 +/- 6 versus 13 +/- 6 mm Hg, P <.0001). CPP and S(j)O2 increased in well-sedated patients (from 78 +/- 16 to 83 +/- 19 mm Hg, and from 71 +/- 10 to 73 +/- 13%, respectively) and decreased in patients who reacted to ETS (from 79 +/- 14 to 72 +/- 14 mm Hg and from 69 +/- 7 to 66 +/- 9%, respectively), and the differences were significant (mean change, CPP: 5 +/- 14 versus -7 +/- 15 mm Hg, P =.003; (S(j)O2) 2 +/- 5 vs. -3 +/- 5%, P <.0001). In well-sedated patients, endotracheal suctioning caused an increase in ICP, CPP, and S j O 2 without evidence of ischemia. In contrast, in patients who coughed or moved in response to suctioning, there was a slight and significant decrease in CPP and S(j)O2. In the case of patients with head injuries who coughed or moved during endotracheal suctioning, we strongly suggest deepening the level of sedation before completing the procedure to reduce the risk of adverse effects.  相似文献   
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36.
BACKGROUND: A surgical risk model is used to analyze postoperative mortality and late survival for older veterans who underwent above- or below-knee amputations in 119 Veterans Affairs (VA) hospitals from 1991 to 1995. METHODS: Preoperative medical conditions and laboratory values abstracted by the VA National Surgical Quality Improvement Program were linked to subsequent hospitalization and survival through 1999. Logistic regression and proportional hazards models were used to develop risk indexes for postoperative mortality and long-term survival. RESULTS: Thirty-day postoperative mortality was 6.3% for 1909 below-knee and 13.3% for 2152 above-knee amputees. Mortality varied greatly between the lowest-highest risk index quartiles (0.8%-18.4% for below-knee amputation and 2.3%-31.1% for above-knee amputation). Surviving patients had 10,827 subsequent VA hospitalizations during a median 32-month follow-up. Survival probabilities for below- and above-knee amputees were 77% and 59% at 1 year, 57% and 39% at 3 years, and 28% and 20% at 7.5 years. The lowest quartile of survival risk had a 61% five-year survival compared with 14% for the highest-risk quartile. CONCLUSION: A generic surgical risk model can be of use in stratifying prognosis after major amputation. The heavy burden of hospital use by these patients suggests the need for better disease management for this high-risk, high-cost patient population.  相似文献   
37.
Background. Over the years, reticular prostheses have undergone changes in their structure and composition to give rise to today's partially absorbable lightweight meshes. This study was designed to assess the biological and biomechanical behavior of these prostheses to establish whether they offer any advantages over nonabsorbable lightweight polypropylene prostheses. Materials and Methods. 7 × 5 cm defects were created in the anterior abdominal wall of New Zealand White rabbits and repaired by securing different prostheses to the edges of the defect with a running 4/0 polypropylene suture. The lightweight biomaterials compared were two nonabsorbable meshes: Parietene® and Optilene elastic®, and two partially absorbable prostheses: Vypro II® and Ultrapro®. At 14 and 90 days postimplant, tissue/prosthesis specimens were subjected to histological, immunohistochemical, shrinkage, and biomechanical analyses. Results. Adhesion formation on the peritoneum-facing surface of the meshes was significantly less extensive in the meshes with absorbable components at 90 days postimplant. The newly formed tissue around the prosthetic filaments was comprised of collagen fibers, fibroblasts, blood vessels, and macrophages. The partially absorbable meshes showed higher macrophage proportions (due to remnants of absorbable material and their structure) than the nonabsorbable meshes at 90 days, although differences were not significant. At 90 days postimplant, similar tensile strengths were recorded for all the implants. Conclusions. All the prosthetic materials induced good host tissue ingrowth, with no significant differences in tensile strength observed. Our findings suggest that partially absorbable lightweight prostheses could offer advantages over nonabsorbable lightweight meshes since less foreign material persists in the recipient, improving abdominal wall compliance.  相似文献   
38.
Chemotherapy‐induced peripheral neuropathy (CIPN) is a frequent adverse event. Nutritional status can become impaired in cancer patients, potentially contributing to neuropathy's evolution. Our aim was to evaluate serum micronutrients and prealbumin in a cohort of 113 solid‐cancer patients receiving platinum and taxane compounds during the development and recovery of neuropathy, up to 1 year after finishing treatment. CIPN was graded according to Total Neuropathy Score© and NCI.CTCv3 at T0 (baseline), T1 (1–3 months), and T12 (12 months) after chemotherapy. CIPN was classified as asymptomatic (< grade 2) or symptomatic (≥2). CIPN recovery was defined as ≥1 grade improvement at T12. Symptomatic CIPN developed in 52% of patients. Symptomatic patients presented a higher increase in TNSc (p < 0.001), in TNSr© (p < 0.001), and decrease in sural (p < 0.001) and radial nerve conduction (p < 0.001). No significant differences with any of the micronutrients were observed along T0‐T1 period between severity or chemotherapy groups. By T12, symptomatic patients without recovery had a decrease in vitamin E levels (p = 0.019) and prealbumin (p = 0.062) compared with those symptomatic that improved. A correlation between the variation of vitamin E and prealbumin at T0‐T1 (r = 0.626, p = 0.001) and T1‐T12 (r = 0.411, p = 0.06) was observed. After chemotherapy treatment, the improvement of patients displaying symptomatic neuropathy is related to vitamin E and prealbumin serum levels. Our results suggest that nutritional status can play a role in CIPN recovery.  相似文献   
39.
Currently there is debate on whether hypoglycemia is an independent risk factor for atherosclerosis, but little attention has been paid to the effects of recovery from hypoglycemia. In normal control individuals and in people with type 1 diabetes, recovery from a 2-h induced hypoglycemia was obtained by reaching normoglycemia or hyperglycemia for another 2 h and then maintaining normal glycemia for the following 6 h. Hyperglycemia after hypoglycemia was also repeated with the concomitant infusion of vitamin C. Recovery with normoglycemia is accompanied by a significant improvement in endothelial dysfunction, oxidative stress, and inflammation, which are affected by hypoglycemia; however, a period of hyperglycemia after hypoglycemia worsens all of these parameters, an effect that persists even after the additional 6 h of normoglycemia. This effect is partially counterbalanced when hyperglycemia after hypoglycemia is accompanied by the simultaneous infusion of vitamin C, suggesting that when hyperglycemia follows hypoglycemia, an ischemia–reperfusion-like effect is produced. This study shows that the way in which recovery from hypoglycemia takes place in people with type 1 diabetes could play an important role in favoring the appearance of endothelial dysfunction, oxidative stress, and inflammation, widely recognized cardiovascular risk factors.Recent evidence suggests that hypoglycemia may play an important role in the vascular complications of diabetes (1). Hypoglycemia causes oxidative stress (2), inflammation (3), and endothelial dysfunction (4). Oxidative stress is considered the key player in the pathogenesis of diabetes complications (5). During hyperglycemia, oxidative stress is produced at the mitochondrial level (5), similarly as in hypoglycemia (2). Therefore, oxidative stress might be considered the common factor linking hyperglycemia, hypoglycemia, and the vascular complications of diabetes. Consistent with this hypothesis is the evidence that hyperglycemia (6) and hypoglycemia both produce endothelial dysfunction and inflammation through the generation of oxidative stress (4,7). Endothelial dysfunction and inflammation are well-recognized pathogenic factors for vascular disease, particularly in diabetes (8).There is, however, evidence that free radical production rises, not only during hypoglycemia but particularly during glucose reperfusion after hypoglycemia (9). In both mice and cultured neurons, hypoglycemia, followed by different concentrations of glucose reperfusion, has been linked to a degree of superoxide production and neuronal death that increased proportionally with glucose concentrations during the reperfusion period (9).Until now, little attention has been given to studying the effects of recovery from hypoglycemia. The aim of this study was to evaluate these effects and, in particular, to determine if the level of glycemia reached during recovery could have a different impact, in vivo, on oxidative stress generation, inflammation, and endothelial function.  相似文献   
40.
Traditional surgical access to the upper descending aorta is via a left thoracotomy. For postcoarctation pseudoaneurysm repair, this approach is difficult because of the risk of rupture while dissecting the aorta for proximal and distal control. Access from a median sternotomy may be safer, but is difficult because of the depth of the wound and because of the angle of approach to the distal aspect of the repair site. We describe a novel approach via a median sternotomy incision, using circulatory arrest and "elephant trunk" principles to achieve tube graft replacement of the aneurysmal section of aorta.  相似文献   
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