Search PubMed⌕ Search

Biomedical subjects

A Kurz

Publications and source records attributed to A Kurz.

At least 73 records · Page 4Linked to original sources
PubMed2001

Body warmer and upper extremities position affect the accuracy of cutaneous thermometers during anesthesia.

STUDY OBJECTIVE: To evaluate whether axillary skin temperature can accurately reflect distal esophageal temperature. DESIGN: Prospective, randomized study. SETTING: Teaching hospital. PATIENTS: 48 ASA physical status I and II adult patients undergoing abdominal surgery. INTERVENTIONS: Patients received standard general anesthesia. 19 patients had abducted upper extremities and an upper body surface warmer, 19 patients had abducted upper extremities with no upper body surface warmer, and 10 patients had adducted upper extremities with no upper body surface warmer. MEASUREMENTS AND MAIN RESULTS: The temperatures were measured 60 minutes after the induction of general anesthesia. There was no significant difference between axillary skin temperature (36 +/- 1.7) (degrees C) and core temperature (36 +/- 0.7) (degrees C) when the upper body surface warmer was used. There was no difference between axillary skin temperature (35.5 +/- 0.4) (degrees C) and core temperature (35.8 +/- 0.4) (degrees C) when upper extremity was adducted 0 degrees. CONCLUSIONS: At 0 degrees of arm adduction, or at 90 degrees using the upper body, forced-air surface warmer, axillary skin temperature accurately identified the core temperature in patients during general anesthesia.

Anesthesia↗
PubMed2001

Ondansetron is no more effective than supplemental intraoperative oxygen for prevention of postoperative nausea and vomiting.

UNLABELLED: Supplemental oxygen maintained during and for 2 h after colon resection halves the incidence of nausea and vomiting. Whether supplemental oxygen restricted to the intraoperative period is sufficient remains unknown. Similarly, the relative efficacy of supplemental oxygen and ondansetron is unknown. We tested the hypothesis that intraoperative supplemental oxygen reduces the incidence of postoperative nausea and vomiting. Patients (n = 240) undergoing gynecological laparoscopy were given a standardized isoflurane anesthetic. After induction, they were randomly assigned to the following three groups: routine oxygen administration with 30% oxygen, balance nitrogen (30% Oxygen group), supplemental oxygen administration with 80% oxygen, balance nitrogen (80% Oxygen group), and Ondansetron 8 mg (immediately after induction), combined with 30% oxygen, balance nitrogen (Ondansetron group). The overall incidence of nausea and/or vomiting during the initial 24 postoperative h was 44% in the patients assigned to 30% oxygen and 30% in the Ondansetron group, but only 22% in those given 80% oxygen. The incidence was thus halved by supplemental oxygen and was significantly less than with 30% oxygen. There were, however, no significant differences between the 30% oxygen and ondansetron groups, or between the ondansetron and 80% oxygen groups. We conclude that supplemental oxygen effectively prevents postoperative nausea and vomiting after gynecological laparoscopic surgery; furthermore, ondansetron is no more effective than supplemental oxygen. IMPLICATIONS: Supplemental oxygen reduces the risk of postoperative nausea and vomiting (PONV) as well or better than 8 mg of ondansetron. Because oxygen is inexpensive and essentially risk-free, supplemental oxygen is a preferable method of reducing PONV.

Adult↗
PubMed2001

Negative pressure rewarming vs. forced air warming in hypothermic postanesthetic volunteers.

We compared changes in core temperature and systemic heat balance with a new negative pressure/warming device (Vital Heat(R) ) that uses negative pressure combined with heat to facilitate warming in vasoconstricted postoperative patients to those resulting from passive insulation or forced air. Seven healthy volunteers were anesthetized and cooled to a tympanic membrane temperature near 34 degrees C. Anesthesia was discontinued and shivering was prevented by using meperidine. The vasoconstricted volunteers were rewarmed for 2 h using three randomly assigned methods: 1) Vital Heat plus cotton blanket; 2) one layer of cotton blanket; 3) forced-air warming. Thermal flux was recorded from 15 skin-surface sites; metabolic heat production was estimated from total body oxygen consumption. Metabolic heat production remained constant throughout the study. Systemic heat loss remained constant during warming with cotton blankets but decreased significantly during the other treatments. Systemic heat balance increased significantly more with forced air (140 +/- 21 kcal) than with Vital Heat (66 +/- 19 kcal) or cotton blankets (47 +/- 18 kcal). Core temperature increased no faster with Vital Heat warming (1.3 +/- 0.4 degrees C) than with a cotton blanket (1.2 +/- 0.4 degrees C). In contrast, core temperature increased more rapidly with forced air warming (2.6 +/- 0.6 degrees C). In this study we show that calories from a negative pressure rewarming device are largely constrained to the forearm and that heat does not flow to the core thermal compartment.

Adult↗
PubMed2000

Association of an interleukin 1 alpha polymorphism with Alzheimer's disease.

BACKGROUND: Retrospective epidemiologic studies suggest that individuals exposed to anti-inflammatory agents such as nonsteroidal anti-inflammatory drugs have a lower probability of developing AD as well as an older age at onset for the illness. Neuroinflammation may play an important role in the pathogenesis of AD. Interleukin 1 (IL-1), a potent proinflammatory cytokine, is colocalized immunohistochemically to neuritic plaques, a requisite neuropathologic feature for AD. A polymorphism in the 5'-flanking regulatory region at -889 of the IL-1 alpha gene (a C-to-T transition designated as IL-1A[-889] allele 2) may cause an overexpression of IL-1 alpha, a finding shown to be associated with inflammatory diseases. The IL-1A(-889) allele 2 polymorphism may be associated with AD pathogenesis. METHODS: A total of 259 patients with AD and 192 nondemented control subjects were included from two different centers (Indianapolis, IN, and Munich, Germany). Genotyping for APOE alleles and IL-1A(-889) allele 2 was performed by PCR-based amplification followed by restrictive endonuclease digestion. Statistical analyses were conducted by center-, gender group-, and age group-stratified Mantel-Haenszel odds ratios, CI, and p values. RESULTS: The allele frequency of IL-1A(-889) allele 2 was 46% in clinically diagnosed patients with probable AD versus 34% in control subjects from the combined centers. CONCLUSION: The authors found an increased risk for AD with an estimated Mantel-Haenszel odds ratio of 1.68 (95% CI 1.1 to 2.6; p = 0.022) for heterozygous carriers and 7.2 (95% CI 2.0 to 24.5; p = 0.003) for individuals homozygous for IL-1A(-889) allele 2. They found no evidence for an interaction between the IL-1A and the apoE epsilon 4 polymorphisms (carriers and homozygotes), age, or gender with regard to conferred risk. The data strongly support an association between the IL-1A(-889) allele 2, especially in homozygotes, and later-onset AD.

Aged↗
PubMed2000

Cerebrospinal beta-amyloid ((1-42)) in early Alzheimer's disease: association with apolipoprotein E genotype and cognitive decline.

The concentration of beta-Amyloid ((1-42)) protein (Abeta42) in cerebrospinal fluid (CSF) was determined in 75 Alzheimer's disease (AD) patients, 35 patients with other causes of dementia and 30 cognitively healthy age-matched controls. A significant decrease of Abeta42 concentration was found in AD patients, even in 25 subjects with very mild dementia as compared to patients with other causes of dementia and controls. Within AD patients we observed a significant decline of Abeta42 from very mild to mild and moderate dementia. In addition, Abeta42 levels were negatively correlated with the severity of cognitive impairment and with the number of varepsilon4 alleles inherited. We conclude that measurement of Abeta42 in CSF might be helpful for identifying AD at an early stage and also for tracking the clinical course.

Age Factors↗
PubMed2000

Head injury and the risk of AD in the MIRAGE study.

OBJECTIVES: It has been suggested in some studies that head injury is a risk factor for AD, and that this risk is heightened among carriers of the APOE-epsilon4 allele. We examined the effects of head injury and APOE genotype on AD risk in a large family study. SUBJECTS: A total of 2,233 probands who met criteria for probable or definite AD and their 14,668 first-degree family members (4,465 parents, 7,694 siblings, and 2,509 spouses) were ascertained at 13 centers in the United States, Canada, and Germany participating in the MIRAGE (Multi-Institutional Research in Alzheimer Genetic Epidemiology) project. Information on head injury was collected by interview of multiple informants and review of medical records. Nondemented relatives and spouses served as control subjects for this study. METHODS: Odds of AD for head trauma with or without loss of consciousness were computed by comparing probands with unaffected spouses using conditional logistic regression analysis. To account for the unique biologic relationship between probands and their parents and siblings, odds of AD were computed using a generalized estimating equation (GEE) Poisson regression approach. GEE logistic regression was used to examine the joint effects of APOE genotype and head injury on the odds of AD in probands and a control group comprised of unaffected siblings and spouses. RESULTS: Comparison of probands with their unaffected spouses yielded odds ratios for AD of 9.9 (95% CI, 6.5 to 15.1) for head injury with loss of consciousness and 3.1 (2.3 to 4.0) for head injury without loss of consciousness. The corresponding odds derived from the comparison of probands with their parents and sibs were 4.0 (2.9 to 5.5) for head injury with loss of consciousness and 2.0 (1.5 to 2.7) for head injury without loss of consciousness. Head injury without loss of consciousness did not significantly increase the risk of AD in spouses (OR = 1.3; 95% CI, 0.4 to 4.1). The joint effects of head injury and APOE genotype were evaluated in a subsample of 942 probands and 327 controls (spouses and siblings). Head injury increased the odds of AD to a greater extent among those lacking epsilon4 (OR = 3.3) than among epsilon4 heterozygotes (OR = 1.8) or homozygotes (OR = 1.3). CONCLUSION: Head injury is a risk factor for AD. The magnitude of the risk is proportional to severity and heightened among first-degree relatives of AD patients. The influence of head injury on the risk of AD appears to be greater among persons lacking APOE-epsilon4 compared with those having one or two epsilon4 alleles, suggesting that these risk factors may have a common biologic underpinning.

Aged↗
PubMed2000

Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection.

BACKGROUND: Destruction by oxidation, or oxidative killing, is the most important defense against surgical pathogens and depends on the partial pressure of oxygen in contaminated tissue. An easy method of improving oxygen tension in adequately perfused tissue is to increase the concentration of inspired oxygen. We therefore tested the hypothesis that the supplemental administration of oxygen during the perioperative period decreases the incidence of wound infection. METHODS: We randomly assigned 500 patients undergoing colorectal resection to receive 30 percent or 80 percent inspired oxygen during the operation and for two hours afterward. Anesthetic treatment was standardized, and all patients received prophylactic antibiotic therapy. With use of a double-blind protocol, wounds were evaluated daily until the patient was discharged and then at a clinic visit two weeks after surgery. We considered wounds with culture-positive pus to be infected. The timing of suture removal and the date of discharge were determined by the surgeon, who did not know the patient's treatment-group assignment. RESULTS: Arterial oxygen saturation was normal in both groups; however, the arterial and subcutaneous partial pressure of oxygen was significantly higher in the patients given 80 percent oxygen than in those given 30 percent oxygen. Among the 250 patients who received 80 percent oxygen, 13 (5.2 percent; 95 percent confidence interval, 2.4 to 8.0 percent) had surgical-wound infections, as compared with 28 of the 250 patients given 30 percent oxygen (11.2 percent; 95 percent confidence interval, 7.3 to 15.1 percent; P=0.01). The absolute difference between groups was 6.0 percent (95 percent confidence interval, 1.2 to 10.8 percent). The duration of hospitalization was similar in the two groups. CONCLUSIONS: The perioperative administration of supplemental oxygen is a practical method of reducing the incidence of surgical-wound infections.

Colon↗
PubMed2000

Perioperative collagen deposition in elderly and young men and women.

HYPOTHESIS: Women deposit more collagen after major abdominal surgery than men. DESIGN: A post hoc analysis of data obtained from 2 prospective, randomized, double-blind clinical trials. SETTING: University hospital general surgical service. PATIENTS: One hundred sixteen patients undergoing colon resection. MAIN OUTCOME MEASURES: Protein and hydroxyproline (collagen) deposition during the first 7 postoperative days in expanded polytetrafluoroethylene implants positioned subcutaneously. RESULTS: On univariate analysis, men and women deposited comparable amounts of collagen (257 +/- 120 vs 281 +/- 117 ng/mm, respectively). When potential confounding factors were entered into a generalized mixed-effects model, only the interaction between age and sex was a significant factor (P = .047). Collagen deposition decreased with age in men, being 317 +/- 133 ng/mm in men younger than 45 years, but only 238 +/- 113 ng/mm in those older than 45 years (P = .03). In contrast, collagen deposition was virtually identical in women younger than 45 years (280 +/- 133 ng/mm) and in those older than 45 years (281 +/- 110 ng/mm). Only 3 of these women were receiving hormone replacement therapy. CONCLUSIONS: Collagen deposition after surgery decreased significantly with age in men, while remaining unchanged in women. Younger men and women deposited similar amounts of collagen. Therefore, older men made less collagen after surgery than older women, perhaps explaining the consistent observation that wound dehiscence is twice as common in men than in women. Our results differ from previous studies conducted in healthy, nonsurgical volunteers, which showed that (1) young women made significantly more collagen than young men and (2) collagen deposition was reduced in postmenopausal women, but deposition returned to premenopausal values with hormone replacement therapy. Differences between our results and those reported previously likely stem from the populations studied. In particular, multiple perioperative factors decrease collagen deposition, which apparently obscures the differences observed previously in healthy, unstressed volunteers.

Abdominal Muscles↗
PubMed2000

The influence of 2 surgical bandage systems on wound tissue oxygen tension.

HYPOTHESIS: Local wound heating improves tissue oxygen tension in postoperative patients. SETTING: University hospital. PATIENTS: Forty normothermic and well-hydrated patients recovering from elective open abdominal surgery. INTERVENTIONS: A comparison between an experimental bandage system (Warm-Up; Augustine Medical Inc, Eden Prairie, Minn) and conventional gauze covered with elastic adhesive (Medipore Dress-it; 3M, St Paul, Minn). The experimental system is heated to 38 degrees C and does not touch the wound. MAIN OUTCOME MEASURES: Subcutaneous tissue oxygen tension was measured postoperatively and on the first postoperative day. In a subgroup, we also evaluated the effects of bandage pressure per se on tissue oxygen. RESULTS: Initial postoperative tissue oxygen tensions were approximately 30 mm Hg greater with the experimental bandage, even before warming. Subcutaneous oxygen tension during heating remained significantly greater in patients with the warmed bandage than the conventional elastic bandage (116 +/- 40 vs 85 +/- 34 mm Hg, respectively) while the patients were breathing approximately 50% oxygen. The difference was smaller on the first postoperative day, but still statistically significant (82 +/- 30 vs 65 +/- 22 mm Hg, respectively). In the subgroup analysis, tissue oxygen tension increased significantly by 12 +/- 4 mm Hg when the heating bandage was substituted for a conventional bandage (P<.001). CONCLUSION: In normothermic and well-hydrated surgical patients, much benefit from the heating bandage system appears to result from pressure relief. These data suggest that relieving wound pressure markedly improves tissue perfusion and oxygenation.

Abdomen↗
PubMed2000

[Antidepressive agents in dementia].

Antidepressants are used in demented patients for treating depressive symptoms as well as other non-cognitive symptoms including agitation, aggression and irritability. As patients are usually elderly, a dose adjustment is mandatory for all classes of antidepressants. New antidepressants such as the SSRIs and the reversible MAO inhibitors should be the first-line agents in these patients, because their efficacy is not different from that of classic TCA, but they have advantages regarding frequency of adverse effects, ease of use and safety. Improvement in cognitive performance, however, may not be expected from the new antidepressants. For the treatment of agitation, aggression and irritability, antipychotics and benzodiazepines are in frequent use, although their adverse effects are particularly problematic in demented patients. Good alternatives are the antidepressant trazodone and citalopram. All medications mentioned have been studied on small patient samples, so treatment recommendations must be given cautiously.

Aged↗
PubMed2000

Peroxidase-catalyzed oxidative damage of DNA and 2'-deoxyguanosine by model compounds of lipid hydroperoxides: involvement of peroxyl radicals.

The peroxidase-catalyzed decomposition of 3-hydroperoxy-1-butene (1), 2,3-dimethyl-3-hydroperoxy-1-butene (2), tert-butyl hydroperoxide (3), ethyl oleate hydroperoxide 4, and linoleic acid hydroperoxide 5 was applied as a chemical model system to assess whether lipid hydroperoxides may cause DNA damage under peroxidase catalysis. For this purpose, the Coprinus peroxidase (CIP), horseradish peroxidase (HRP), and the physiologically important lactoperoxidase (LP) were tested. Indeed, hydroperoxides 1-5 induce strand breaks in pBR 322 DNA upon peroxidase catalysis. For the nucleoside dG, the enzymatic decomposition of hydroperoxides 1-4 led to significant amounts of 4, 8-dihydro-4-hydroxy-8-oxo-2'-deoxyguanosine (4-HO-8-oxo-dG) and guanidine-releasing products (GRP), whereas 7, 8-dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dG) was not obtained. In isolated calf thymus DNA, the efficient conversion of the guanine base (Gua) was observed. Peroxyl radicals, which are generated in situ from the hydroperoxides by one-electron oxidation with the peroxidases, are proposed as the active oxidants on the basis of the following experimental facts. (i) Radical scavengers strongly inhibit the guanine oxidation in dG and DNA and strand-break formation in the latter. (ii) EPR spectral studies with 5, 5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin trap confirmed the formation of peroxyl radicals. (iii) The release of molecular oxygen was demonstrated, produced through the disproportionation of peroxyl radicals. The biological relevance of these findings should be seen in the potential role of the combined action of lipid hydroperoxides and peroxidases in damaging cellular DNA through peroxyl radicals.

Animals↗
PubMed2000

[Clinical aspects of frontotemporal dementia].

Frontotemporal neurodegeneration can cause three typical clinical syndromes: frontotemporal dementia (FTD), primary progressive aphasia (PPA) and semantic dementia (SD). In the present paper we review these syndromes, highlighting FTD. Four case examples are presented. At the early stage of FTD changes of personality and social conduct are prominent, whereas cognitive functions are relatively well preserved. Since the usual dementia tests are not sufficiently sensitive to disclose non-cognitive symptoms, clinical diagnosis as well as differentiation from non-organic psychiatric disorders can be difficult. Detailed history, thorough clinical examination, and neuropsychological testing are required to establish the diagnosis. EEG and functional brain imaging may be helpful. The choice of therapeutic options for FTD is extremely limited. Medications may be used to treat neuropsychiatric symptoms. There is little experience with non-pharmacologic behaviour modification and milieu treatment approaches. The problems that FTD imposes on caregivers are dissimilar to those arising from Alzheimer's disease. Families receive little or no support so that early nursing home admission of patients is common.

Dementia↗
PubMed2000

Temperature monitoring and management during neuraxial anesthesia: an observational study.

UNLABELLED: Temperature monitoring and thermal management are rare during spinal or epidural anesthesia because clinicians apparently restrict monitoring to patients with an expected risk of hypothermia. This implies that anesthesiologists can predict patient thermal status without monitoring core temperature. We therefore, tested the hypotheses that during neuraxial anesthesia: 1) amount of core hypothermia depends on the magnitude and duration of surgery; 2) temperature monitoring and thermal management are used selectively in patients at high risk of hypothermia; and 3) anesthesiologists can estimate patient thermal status. We evaluated thermal status on arrival in the recovery room along with intraoperative thermal management and monitoring in 120 patients. Anesthesiologists were asked if their patients were hypothermic (<36 degrees C). There was no correlation between the magnitude or duration of surgery and initial postoperative core temperature in unwarmed patients. Temperature monitoring and thermal management were not used selectively in high-risk patients. Initial postoperative tympanic membrane temperatures were <36 degrees C in 77% of patients and <35 degrees C in 22%. Body temperature was monitored intraoperatively in 27% of the patients and forced-air warming was used in 31%. Anesthesiologists failed to accurately estimate whether their patients were hypothermic. Our results suggest that temperature monitoring and management during neuraxial anesthesia is currently inadequate. IMPLICATIONS: In this observational study, we evaluated core temperatures and intraoperative thermal management in patients undergoing spinal or epidural anesthesia. Hypothermia was common, however, rarely detected either by temperature monitoring or estimates by anesthesiologists. In addition, it was not treated with active warming. Consequently, temperature monitoring and management have to be done during neuraxial anesthesia.

Aged↗
PubMed2000

Aggressive warming reduces blood loss during hip arthroplasty.

UNLABELLED: We evaluated the effects of aggressive warming and maintenance of normothermia on surgical blood loss and allogeneic transfusion requirement. We randomly assigned 150 patients undergoing total hip arthroplasty with spinal anesthesia to aggressive warming (to maintain a tympanic membrane temperature of 36.5 degrees C) or conventional warming (36 degrees C). Autologous and allogeneic blood were given to maintain a priori designated hematocrits. Blood loss was determined by a blinded investigator based on sponge weight and scavenged cells; postoperative loss was determined from drain output. Results were analyzed on an intention-to-treat basis. Average intraoperative core temperatures were warmer in the patients assigned to aggressive warming (36.5 degrees +/- 0.3 degrees vs 36.1 degrees +/- 0.3 degrees C, P< 0.001). Mean arterial pressure was similar in each group preoperatively, but was greater intraoperatively in the conventionally warmed patients: 86+/-12 vs 80+/-9 mm Hg, P<0.001. Intraoperative blood loss was significantly greater in the conventional warming (618 mL; interquartile range, 480-864 mL) than the aggressive warming group (488 mL; interquartile range, 368-721 mL; P: = 0.002), whereas postoperative blood loss did not differ in the two groups. Total blood loss during surgery and over the first two postoperative days was also significantly greater in the conventional warming group (1678 mL; interquartile range, 1366-1965 mL) than in the aggressively warmed group (1,531 mL; interquartile range, 1055-1746 mL, P = 0.031). A total of 40 conventionally warmed patients required 86 units of allogeneic red blood cells, whereas 29 aggressively warmed patients required 62 units (P = 0.051 and 0.061, respectively). We conclude that aggressive intraoperative warming reduces blood loss during hip arthroplasty. IMPLICATIONS: Aggressive warming better maintained core temperature (36.5 degrees vs 36.1 degrees C) and slightly decreased intraoperative blood pressure. Aggressive warming also decreased blood loss by approximately 200 mL. Aggressive warming may thus, be beneficial in patients undergoing hip arthroplasty.

Adult↗
PubMed2000

A genetic variation of cathepsin D is a major risk factor for Alzheimer's disease.

Cathepsin D (catD) is an intracellular acid protease possibly involved in Alzheimer's disease (AD)-related neurodegeneration through cleavage of amyloid precursor protein into amyloidogenic components. We studied whether an exonic polymorphism of the catD gene (C --> T [Ala --> Val] transition at position 224), which possibly influences pro-catD secretion and intracellular maturation of the enzyme, was associated with the risk for the development of AD in 127 demented patients and 184 controls. The catD*T allele was significantly overrepresented in demented patients (11.8%) compared with nondemented controls (4.9%). Carriers of the catD*T allele had a 3.1-fold increased risk for developing AD than noncarriers. Carriers of the apolipoprotein E (ApoE) epsilon4 allele (ApoE*4) had a 3.9-fold increased risk than non-carriers. The adjusted odds ratio for subjects with the ApoE*4 and the catD*T allele was 19.0 compared with subjects with neither of these two alleles. Our data confirm the results of a recently performed pilot study in an independent sample and suggest that the catD genotype is strongly associated with the risk for AD.

Aged↗
PubMed1999

Postoperative pain and subcutaneous oxygen tension.

Surgical patients randomly assigned to standard pain control had postoperative subcutaneous oxygen partial pressures that were significantly less than patients given better pain treatment. Our data suggest that control of postoperative pain is a major determinant of surgical-wound infection and should be given the same consideration as maintaining adequate vascular volume and normothermia.

Adolescent↗