bluuebunny/crossref_metadata_2025_split huggingface dataset:
Randomized Trial of Hypotensive Epidural Anesthesia in Older Adults
Authors: Williams-Russo Pamela , Sharrock Nigel E. , Mattis Steven , Liguori Gregory A. , Mancuso Carol , Peterson Margaret G. , Hollenberg James , Ranawat Chitranjan , Salvati Eduardo , Sculco Thomas 
Published: November 2003

Background
Data are sparse on the incidence of postoperative cognitive, cardiac, and renal complications after deliberate hypotensive anesthesia in elderly patients.

Methods
This randomized, controlled clinical trial included 235 older adults with comorbid medical illnesses undergoing elective primary total hip replacement with epidural anesthesia. The patients were randomly assigned to one of two levels of intraoperative mean arterial blood pressure management: either to a markedly hypotensive mean arterial blood pressure range of 45-55 mmHg or to a less hypotensive range of 55-70 mmHg. Cognitive outcome was assessed by within-patient change on 10 neuropsychologic tests assessing memory, psychomotor, and language skills from before surgery to 1 week and 4 months after surgery. Prospective standardized surveillance was performed for cardiovascular and renal outcomes, delirium, thromboembolism, and blood loss and replacement.

Results
The two groups were similar at baseline in terms of age (mean, 72 yr), sex (50% women), comorbid conditions, and cognitive function. After operation, no significant differences in the incidence of early or long-term cognitive dysfunction were observed between the two blood pressure management groups. There were no significant differences in the rates of other adverse consequences, including cardiac, renal, and thromboembolic complications. In addition, no differences occurred in the duration of surgery, intraoperative estimated blood loss, or transfusion rates.

Conclusions
Elderly patients can safely receive controlled hypotensive epidural anesthesia with this protocol. There was no evidence of greater risks, or early benefits, with the use of the more markedly hypotensive range.
Risk Factors of Delayed Extubation, Prolonged Length of Stay in the Intensive Care Unit, and Mortality in Patients Undergoing Coronary Artery Bypass Graft with Fast-track Cardiac Anesthesia
Authors: Wong David T. , Cheng Davy C. H. , Kustra Rafal , Tibshirani Robert , Karski Jacek , Carroll-Munro Jo , Sandler Alan 
Published: November 2003

Background
Risk factors of delayed extubation, prolonged intensive care unit (ICU) length of stay (LOS), and mortality have not been studied for patients administered fast-track cardiac anesthesia (FTCA). The authors' goals were to determine risk factors of outcomes and cardiac risk scores (CRS) for CABG patients undergoing FTCA.

Methods
Consecutive CABG patients undergoing FTCA were prospectively studied. Outcome variables were delayed extubation > 10 h, prolonged ICU LOS > 48 h, and mortality. Univariate analyses were performed followed by multiple logistic regression to derive risk factors of the three outcomes. Simplified integer-based CRS were derived from logistic models. Bootstrap validation was performed to assess and compare the predictive abilities of CRS and logistic models for the three outcomes.

Results
The authors studied 885 patients. Twenty-five percent had delayed extubation, 17% had prolonged ICU LOS, and 2.6% died. Risk factors of delayed extubation were increased age, female gender, postoperative use of intraaortic balloon pump, inotropes, bleeding, and atrial arrhythmia. Risk factors of prolonged ICU LOS were those of delayed extubation plus preoperative myocardial infarction and postoperative renal insufficiency. Risk factors of mortality were female gender, emergency surgery, and poor left ventricular function. CRSs were modeled for the three outcomes. The area under the receiver operating characteristic curve for the CRS-logistic models was not significantly different: 0.707/0.702 for delayed extubation, 0.851/0.855 for prolonged ICU LOS, and 0.657/0.699 for mortality.

Conclusion
In CABG patients undergoing FTCA, the authors derived and validated risk factors of delayed extubation, prolonged ICU LOS, and mortality. Furthermore, they developed a simplified CRS system with similar predictive abilities as the logistic models.
Effect of Mivazerol on Perioperative Cardiac Complications during Non-cardiac Surgery in Patients with Coronary Heart Disease
Authors: Oliver Michael F. , Goldman Lee , Julian Desmond G. , Holme Ingar 
Published: November 2003

Background
Mivazerol is a drug with alpha2-agonist properties that reduces post-ganglionic noradrenaline availability and spinal efferent sympathetic output.

Methods
A double-blind randomized placebo-controlled trial was conducted in 61 European centers during a 2.5-yr period on 2,854 patients: 1,897 with coronary heart disease and 957 patients without overt coronary heart disease but classified as at high risk for it. The present analysis was restricted to those patients with previous known coronary heart disease of whom 48% had vascular surgery, 32% non-vascular thoracic or abdominal surgery, and 20% orthopedic surgery. Mivazerol or placebo were given intravenously from the induction of anesthesia for up to 72 h.

Results
In the 1,897 patients with established coronary heart disease, mivazerol did not reduce the primary endpoint--the combination of myocardial infarction or death--or all-cause deaths significantly. A preplanned subgroup analysis of 904 patients with known coronary heart disease undergoing vascular surgery showed that there were fewer primary endpoints in those receiving mivazerol (risk ratio [RR], 0.67; 95% CL, 0.45-0.98; P = 0.037) and fewer cardiac deaths (6 of 454 vs. 18 of 450: RR, 0.33; 95% confidence limits, 0.13-0.82; P = 0.017). The all-cause death rate was also decreased (RR, 0.41; 95% CL, 0.18-0.91; P = 0.024), although there was no significant reduction in myocardial infarction.

Conclusion
The alpha2-adrenergic agonist, mivazerol, did not alter the rates of myocardial infarction or cardiac death in patients with known coronary heart disease undergoing noncardiac surgery. However, it may have protected patients undergoing vascular surgery from further coronary events, and a specific study of such patients is now indicated.
Randomized Trial of Informed Consent and Recruitment for Clinical Trials in the Immediate Preoperative Period
Authors: Myles Paul S. , Fletcher Helen E. , Cairo Sesto , Madder Hilary , McRae Roderick , Cooper James , Devonshire Debra , Hunt Jennifer O. , Richardson Jo , Machlin Howard , Morgan Brian E. , Moloney John , Downey Glen 
Published: November 2003

Background
The standard process of obtaining informed consent sometimes prevents physicians or patients from participating in clinical trials, partly because they are concerned about eventual treatment allocation or the physician is concerned the patient might harbor some uncertainty about the best treatment. Alternative randomization methods have been advocated that may address these and other concerns.

Methods
After institutional ethics committee gave its approval, the authors interviewed 770 patients before operation and asked them to consider enrolling in a mock anesthesia trial. Patients were allocated randomly to one of five methods of randomization and consent: one-sided informed consent (the most common approach), prerandomized consent to experimental treatment, prerandomized consent to standard treatment, one-sided physician-modified informed consent, or one-sided patient-modified informed consent. Recruitment rates were compared and sociodemographic and perioperative predictors of recruitment were identified.

Results
The randomization method did not result in any significant difference in recruitment rates: one-sided informed consent, 55.6%; prerandomized consent to experimental treatment, 53.3%; prerandomized consent to standard treatment, 53%; one-sided physician-modified informed consent, 60.7%; and one-sided patient-modified informed consent, 56.7% (P = 0.66). Multivariate predictors of recruitment were patient age >45 yr (odds ratio, 1.44; 95% confidence interval [CI], 1.08 to 1.93), English-speaking at home (1.49; 1.0 to 2.21), and male researcher-male patient interaction (1.37; 1.20 to 1.57).

Conclusions
No evidence emerged that alternative randomization and consent designs resulted in increased recruitment rates compared with simple one-sided informed consent for a sham anesthesia trial in patients awaiting elective surgery. Older, male patients were more likely to provide consent.
Postoperative Pain Facilitates Nonthermoregulatory Tremor
Authors: Horn Ernst-Peter , Schroeder Frank , Wilhelm Stefan , Sessler Daniel I. , Standl Thomas , Busche Katja von dem , Esch Jochen Schulte am 
Published: November 2003

Background
Spontaneous tremor is relatively common in normothermic patients after operation and has been attributed to many causes. The hypothesis that nonthermoregulatory shivering-like tremor is facilitated by postoperative pain was tested. In addition, the effects of intravenous lidocaine on nonthermoregulatory tremor were evaluated.

Methods
Patients undergoing knee surgery were anesthetized with 2 microg/kg intravenous fentanyl and 0.2 mg/kg etomidate. Anesthesia was maintained with 1.7 +/- 0.8% (mean +/- SD) isoflurane. Intraoperative forced-air heating maintained normothermia The initial 44 patients were randomly allocated to receive an intra-articular injection of 20 ml saline (n = 23) or lidocaine, 1.5% (n = 21). The subsequent 30 patients were randomly allocated to receive an intravenous bolus of 250 microg/kg lidocaine followed by an infusion of 13 microg x kg(-1) x h(-1) lidocaine or an equivalent volume of saline when shivering was observed. Patient-controlled analgesia was provided for all patients: 3.5 mg piritramide, with a lockout interval of 5 min, for an unlimited total dose. Shivering was graded by a blinded investigator using a four-point scale. Pain was assessed by a 100-mm visual analog scale (0 = no pain and 100 = worst pain). The arteriovenous shunt status was evaluated with forearm-minus-fingertip skin-temperature gradients.

Results
Morphometric characteristics and hemodynamic responses were similar in the four groups. Core and mean skin temperature remained constant or increased slightly compared with preoperative values, and postoperative skin-temperature gradients were negative (indicating vasodilation) in nearly all patients. After intra-articular injection of saline, pain scores for the first postoperative hour averaged 46 +/- 32 mm (mean +/- SD), and 10 of the 23 (43%) patients shivered. In contrast, the pain scores of patients who received intra-articular lidocaine were significantly reduced to 5 +/- 9 mm and shivering was absent in this group (P < 0.05). In the second portion of the study, neither intravenous lidocaine nor saline reduced the magnitude or duration of nonthermoregulatory tremor or the patients' pain scores.

Conclusions
Intra-articular, but not intravenous, lidocaine reduced surgical pain and prevented nonthermoregulatory shivering. Therefore, these data indicate that postoperative pain facilitates nonthermoregulatory shivering.
Correlation between Cerebral Oxygen Saturation Measured by Near-infrared Spectroscopy and Jugular Oxygen Saturation in Patients with Severe Closed Head Injury
Authors: Minassian Aram Ter , Poirier Nicolas , Pierrot Marc , Menei Philippe , Granry Jean Claude , Ursino Mauro , Beydon Laurent 
Published: November 2003

Unlabelled
Near-infrared spectroscopy has been used to monitor cerebral oxygen saturation during cerebral circulatory arrest and carotid clamping. However, its utility has not been demonstrated in more complex situations, such as in patients with head injuries. The authors tested this method during conditions that may alter the arteriovenous partition of cerebral blood in different ways.

Methods
The authors compared changes in measured cerebral oxygen saturation and other hemodynamic parameters, including jugular venous oxygen saturation, in nine patients with severe closed head injury during manipulation of arterial carbon dioxide partial pressure and after mean arterial pressure was altered by vasopressors.

Results
The Bland and Altman representation of cerebral oxygen saturation versus jugular oxygen saturation showed a uniform scatter. Values for changing arterial carbon dioxide partial pressure were: bias = 1.1%, 2 SD = +/-21%, absolute value; and those for alterations in mean arterial pressure: bias = 3.7%, 2 SD = +/-24%, absolute value. However, a Bland and Altman plot of changes in cerebral oxygen saturation versus changes in jugular oxygen saturation had a negative slope (alteration in arterial carbon dioxide partial pressure: bias = 2.4%, 2 SD = +/-17%, absolute value; alteration in mean arterial pressure: bias = -4.9%, 2 SD = +/-31%, absolute value). Regression analysis showed that changes in cerebral oxygen saturation were positively correlated with changes in jugular venous oxygen saturation during the carbon dioxide challenge, whereas correlation was negative during the arterial pressure challenge.

Conclusions
Cerebral oxygen saturation assessed by near-infrared spectroscopy does not adequately reflect changes in jugular venous oxygen saturation in patients with severe head injury. Changes in arteriovenous partitioning, infrared-spectroscopy contamination by extracerebral signal, algorithm errors, and dissimilar tissue sampling may explain these findings.
Comparable Postoperative Pulmonary Atelectasis in Patients Given 30% or 80% Oxygen during and 2 Hours after Colon Resection
Authors: Akça Ozan , Podolsky Andrea , Eisenhuber Edith , Panzer Oliver , Hetz Hubert , Lampl Karl , Lackner Franz X. , Wittmann Karin , Grabenwoeger Florian , Kurz Andrea , Schultz Anette-Marie , Negishi Chiharu , Sessler Daniel I. 
Published: November 2003

Background
High concentrations of inspired oxygen are associated with pulmonary atelectasis but also provide recognized advantages. Consequently, the appropriate inspired oxygen concentration for general surgical use remains controversial. The authors tested the hypothesis that atelectasis and pulmonary dysfunction on the first postoperative day are comparable in patients given 30% or 80% perioperative oxygen.

Methods
Thirty patients aged 18-65 yr were anesthetized with isoflurane and randomly assigned to 30% or 80% oxygen during and for 2 h after colon resection. Chest radiographs and pulmonary function tests (forced vital capacity and forced expiratory volume) were obtained preoperatively and on the first postoperative day. Arterial blood gas measurements were obtained intraoperatively, after 2 h of recovery, and on the first postoperative day. Computed tomography scans of the chest were also obtained on the first postoperative day.

Results
Postoperative pulmonary mechanical function was significantly reduced compared with preoperative values, but there was no difference between the groups at either time. Arterial gas partial pressures and the alveolar-arterial oxygen difference were also comparable in the two groups. All preoperative chest radiographs were normal. Postoperative radiographs showed atelectasis in 36% of the patients in the 30%-oxygen group and in 44% of those in the 80%-oxygen group. Relatively small amounts of pulmonary atelectasis (expressed as a percentage of total lung volume) were observed on the computed tomography scans, and the percentages (mean +/- SD) did not differ significantly in the patients given 30% oxygen (2.5% +/- 3.2%) or 80% oxygen (3.0% +/- 1.8%). These data provided a 99% chance of detecting a 2% difference in atelectasis volume at an alpha level of 0.05.

Conclusions
Lung volumes, the incidence and severity of atelectasis, and alveolar gas exchange were comparable in patients given 30% and 80% perioperative oxygen. The authors conclude that administration of 80% oxygen in the perioperative period does not worsen lung function. Therefore, patients who may benefit from generous oxygen partial pressures should not be denied supplemental perioperative oxygen for fear of causing atelectasis.
Overexpression of bcl-xLProtects Astrocytes from Glucose Deprivation and Is Associated with Higher Glutathione, Ferritin, and Iron Levels
Authors: Xu Lijun , Koumenis Iphigenia L. , Tilly Jonathan L. , Giffard Rona G. 
Published: November 2003

Background
The possibility of altering outcome from ischemia-like injury by overexpressing the anti-cell death gene bcl-xL was studied. Cells are known to die by different pathways including apoptosis, or programmed cell death, and necrosis. The bcl-xL gene is a member of a family of apoptosis regulating genes and often displays the death-inhibiting properties of the prototype of this family, bcl-2. It is of special interest to study bcl-xL for possible brain protection, because, unlike bcl-2, it is important for normal brain development.

Methods
Overexpression of bcl-xL was achieved in primary astrocyte cultures using a retroviral vector. Cultures of astrocytes overexpressing bcl-xL or a control gene were injured by hydrogen peroxide, glucose deprivation, or combined oxygen and glucose deprivation. Outcome was assessed morphologically and by release of lactate dehydrogenase. We assessed antioxidant effects by measuring glutathione using monochlorobimane, ferritin by immunoblotting, the level of iron spectrophotometrically, and superoxide using iodonitrotetrazolium violet and dihydroethidium.

Results
Protection by bcl-xL was found against glucose deprivation and hydrogen peroxide exposure but not combined oxygen and glucose deprivation. Higher levels of superoxide were found, without increased levels of lipid peroxidation. Overexpression of bcl-xL was associated with elevated glutathione levels, elevated ferritin levels, and increased amounts of iron. The increased glutathione contributed to the protection from glucose deprivation.

Conclusions
Overexpression of bcl-xL protects astrocytes from oxidative injury with the same spectrum of protection seen previously for bcl-2. The increased antioxidant defense observed should be beneficial against both apoptotic and necrotic cell death. The effects on levels of ferritin and iron are novel and identify a new area of interest for this gene family. Whether this relates to the effects of these genes on mitochondrial function remains to be elucidated.
Xenon Does Not Trigger Malignant Hyperthermia in Susceptible Swine
Authors: Froeba Gebhard , Marx Thomas , Pazhur Johannes , Baur Christoph , Baeder Stefan , Calzia Enrico , Eichinger Hans M. , Radermacher Peter , Georgieff Michael 
Published: November 2003

Background
Xenon is a noble gas with anesthetic properties currently under investigation for use in humans. This study was performed to evaluate whether xenon may trigger malignant hyperthermia in susceptible swine.

Methods
Nine malignant hyperthermia-sensitive swine (Pietrain) were initially anesthetized with pentobarbital and then ventilated with 70% xenon in oxygen for 2 h. Heart rate, mean arterial pressure, cardiac output, body temperature, arterial and mixed-venous blood gases, and plasma catecholamine and lactate levels were measured every 10 min both during xenon-oxygen ventilation and after a 30-min xenon washout phase followed by subsequent administration of halothane (1% inspired) and succinylcholine (3 mg/kg intravenous). During the investigation, no malignant hyperthermia-specific therapy was instituted.

Results
Xenon exposure did not induce any changes in metabolic and hemodynamic parameters nor elevations of the plasma catecholamine levels indicative for an episode of malignant hyperthermia. By contrast, in all animals, within 20 min after the administration of halothane and succinylcholine, fulminant and fatal malignant hyperthermia episodes were initiated.

Conclusions
The authors conclude that xenon does not trigger malignant hyperthermia in susceptible swine.
Intrathecal Ropivacaine for Ambulatory Surgery
Authors: Gautier Ph. E. , De Kock M. , Van Steenberge A. , Poth N. , Lahaye-Goffart B. , Fanard L. , Hody J. L. 
Published: November 2003

Background
The rationale of this study was to evaluate intrathecal ropivacaine for ambulatory surgery.

Methods
One hundred fifty patients with American Society of Anesthesiologists physical status 1 scheduled for knee arthroscopy were studied. Patients were randomly assigned to receive 4 ml of one of five isobaric intrathecal solutions: Patients in group 1 (n = 30) received 8 mg of bupivacaine; patients in group 2 (n = 30) received 8 mg ropivacaine; patients in group 3 (n = 30) received 10 mg ropivacaine; patients in group 4 (n = 30) received 12 mg ropivacaine; and patients in group 5 (n = 30) received 14 mg ropivacaine. The level and duration of sensory anesthesia were recorded along with the intensity and duration of motor block. Patients were interviewed to identify transient neurologic symptoms.

Results
Intrathecal ropivacaine 10 mg produced shorter sensory anesthesia and motor blockade than bupivacaine 8mg (152 +/- 44 min and 135 +/- 41 min vs. 181 +/- 44 min and 169 +/- 52 min, mean +/- SD; P < 0.05). However, the quality of intraoperative analgesia was significantly lower in the 10-mg ropivacaine group (P < 0.05). Ropivacaine 12 mg produced sensory and motor block almost comparable to bupivacaine 8 mg. Ropivacaine 14 mg produced sensory and motor block comparable to ropivacaine 12 mg but significantly increased the time to void. No sign of transient radicular irritation were noted.

Conclusion
Intrathecal ropivacaine 12 mg is approximately equivalent to bupivacaine 8 mg. At this dose, ropivacaine offers no significant advantage compared with bupivacaine.
Intrathecal Bupivacaine in Humans
Authors: Malinovsky Jean-Marc , Renaud Géraldine , Le Corre Pascal , Charles Florence , Lepage Jean-Yves , Malinge Myriam , Cozian Antoine , Bouchot Olivier , Pinaud Michel 
Published: November 2003

Background
The effects of volume and baricity of spinal bupivacaine on block onset, height, duration, and hemodynamics were studied.

Methods
Ninety patients undergoing endoscopic urologic procedures were randomized to receive 10 mg of intrathecal bupivacaine at L2-L3 level in sitting position. In the operating room, commercial products were diluted as needed with NaCl 0.9% to obtain isobaric solutions (density, 1.005-1.008) or with NaC 10.9% and glucose 30% to obtain hyperbaric solutions (density, 1.031-1.037) of 2, 5, or 10 ml (six groups of 15 patients each). Three minutes after spinal injection the patients were placed in lithotomy position. Sensory blockade was assessed using pinprick and cold sensation tests, and motor blockade was assessed using a four-point scale.

Results
Onset times to maximal cephalad spread of spinal blockade were similar with isobaric and hyperbaric solutions. A greater maximal cephalad spread of anesthesia was obtained with diluted isobaric bupivacaine but was not associated with more hypotension. Volume had no effect on cephalad extent of anesthesia with hyperbaric bupivacaine. Times for regression of anesthesia to L2 and offset of motor block were longer with isobaric than with hyperbaric solutions of bupivacaine. The intensity of motor blockade was decreased with diluted hyperbaric bupivacaine. No patient reported back pain.

Conclusion
In this study, volume had no significant influence on either cephalad spread or duration of sensory blockade for either isobaric or hyperbaric bupivacaine. Time for offset of anesthesia was shorter with hyperbaric bupivacaine compared with isobaric solutions.