bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein Requirements of Very Low Birth Weight Infants
Authors: Ziegler Ekhard E 
Published: March 2009

ABSTRACTObjective:To review existing information regarding protein (and energy) requirements of very low birth weight infants, and to determine whether revisions may be indicated in view of the commonly observed postnatal growth failure, or in view of adverse consequences of accelerated growth.Results:Nutrient requirements of very low birth weight infants have been estimated by the factorial method and by empirical methods. These approaches yield similar estimates of nutrient requirements. The factorial method provides estimates of requirements for protein and energy, including those of extremely small infants. Empirical methods yield estimates of protein requirements but tend to exclude extremely small infants. They also provide estimates of protein intakes that lead to catch‐up growth. Reports of actual nutrient intakes received by very low birth weight infants show that intakes are generally less than estimated requirements.Conclusions:Growth failure is adequately explained by insufficient nutrient intakes. Upward revision of requirements is not indicated until it can be shown that growth failure occurs despite intakes that match current estimates of requirements. Downward revision also is not indicated because accelerated growth, in spite of some adverse effects later in life, is associated with improved neurocognitive outcome.
Mutation Analysis of Endothelin‐B Receptor Gene in Patients With Hirschsprung Disease in Taiwan
Authors: Lin Yu‐Cheng , Lai Hong‐Shiee , Hsu Wen‐Ming , Lee Ping‐Ing , Chen Huey‐Ling , Chang Mei‐Hwei 
Published: March 2009

ABSTRACTBackground:Endothelin‐B receptor (EDNRB) signaling pathway is associated for Hirschsprung disease (HSCR). The aim of this study was to investigate the EDNRB gene mutation in patients with HSCR in Taiwan and correlate the genotype and phenotype.Patients and Methods:Using polymerase chain reaction amplification and direct sequencing, we screened for mutations in the coding regions and intron/exon boundaries of the EDNRB gene in 39 isolated HSCR cases and compared them with those in 400 control chromosomes.Results:In 3 cases, heterozygous variations in exon 1 and 2 of the EDNRB gene predicted missense mutations of the first cytosolic (M132I), second transmembrane (I157V), second exoplasmic (M173T), and third transmembrane (V185M) domains of the EDNRB protein. Three of the 4 mutations in our study have not been reported previously. For total 39 unrelated cases, the mutation rates were estimated to be 10% (3 of 30) for short‐segment HSCR and 7.7% (3 of 39) for all HSCR cases.Conclusions:We did not detect a significant genotype–phenotype correlation. In conclusion, this study identified 4 mutations within the EDNRB gene associated with HSCR. Because HSCR is a multifactorial and multigene disorder, the higher mutation rate of 10% for short‐segment HSCR suggests the important role that the EDNRB gene plays in the pathogenesis of short‐segment HSCR in Taiwan.
Magnitude of the Second Gas Effect on Arterial Sevoflurane Partial Pressure
Authors: Peyton Philip J. , Horriat Maryam , Robinson Gavin J. B. , Pierce Robert , Thompson Bruce R. 
Published: March 2009

Background
A number of studies have demonstrated a faster rate of increase in end-expired partial pressure as a fraction of inspired (Pa/Pi) for volatile agents in the presence of high concentrations of nitrous oxide, consistent with the second gas effect. However, no study has demonstrated a similar effect on arterial blood concentrations.

Methods
The authors compared arterial and end-tidal partial pressures of sevoflurane (Pa/Pisevo and Pa/Pisevo) in 14 patients for 30 min after introduction of either 70% nitrous oxide or nitrous oxide-free gas mixtures to determine the magnitude of the second gas effect. Blood partial pressures were measured using a double headspace equilibration technique.

Results
Both Pa/Pisevo and Pa/Pisevo were significantly higher in the nitrous oxide group than in the control group (P < 0.001 on two-way analysis of variance). This difference was significantly greater (P < 0.05) for Pa/Pisevo (23.6% higher in the nitrous oxide group at 2 min, declining to 12.5% at 30 min) than for Pa/Pisevo (9.8% higher in the nitrous oxide group at 2 min) and was accompanied by a significantly lower Bispectral Index score at 5 min (40.7 vs. 25.4; P = 0.004).

Conclusion
Nitrous oxide uptake exerts a significant second gas effect on arterial sevoflurane partial pressures. This effect is two to three times more powerful than the effect on end-expired partial pressures. The authors explain how this is due to the influence of ventilation-perfusion scatter on the distribution of blood flow and gas uptake in the lung.
Young Age as a Risk Factor for Impaired Cerebral Autoregulation after Moderate to Severe Pediatric Traumatic Brain Injury
Authors: Freeman Serena S. , Udomphorn Yuthana , Armstead William M. , Fisk Dana M. , Vavilala Monica S. 
Published: March 2009

Background
Little is known about age and cerebral autoregulation in children with traumatic brain injury (TBI). The authors compared cerebral autoregulation between young (aged <4 yr) and older (aged > or =4 yr) children with TBI.

Methods
After University of Washington's institutional review board approval, a retrospective analysis of prospectively collected data (May 2002 and June 2007) was performed. Eligibility criteria included age 16 yr or younger, moderate to severe (admission Glasgow Coma Scale score <13) TBI, TBI on computed tomography scan, and tracheal intubation. Cerebral autoregulation testing was performed within 72 h after TBI, and autoregulation was quantified using the autoregulatory index. An autoregulatory index less than 0.4 represents impaired cerebral autoregulation. The 12-month Glasgow outcome score was measured. Data are presented as mean +/- SD or range.

Results
Thirty-seven children (8.9 +/- 5.1 yr; 0.8-16 yr) were enrolled. Children younger than 4 yr had a higher incidence of impaired cerebral autoregulation (8 of 10 vs. 7 of 27; P = 0.006) and worse 12-month outcome (Glasgow outcome score 3.0 +/- 1.0 vs. 4.0 +/- 1.0; P = 0.02) than older children. Age less than 4 yr (adjusted odds ratio, 12.2; 95% confidence interval, 1.5-98.5) and low Glasgow Coma Scale score (adjusted odds ratio for higher Glasgow Coma Scale, 0.53; 95% confidence interval, 0.30-0.96) were independently associated with impaired cerebral autoregulation.

Conclusions
Age less than 4 yr was a risk factor for impaired cerebral autoregulation, independent of TBI severity. Age-related factors may play a role in the mechanisms maintaining or worsening cerebral autoregulation in children after TBI.
Ambulatory Continuous Femoral Nerve Blocks Decrease Time to Discharge Readiness after Tricompartment Total Knee Arthroplasty
Authors: Ilfeld Brian M. , Le Linda T. , Meyer R Scott , Mariano Edward R. , Vandenborne Krista , Duncan Pamela W. , Sessler Daniel I. , Enneking F Kayser , Shuster Jonathan J. , Theriaque Douglas W. , Berry Linda F. , Spadoni Eugene H. , Gearen Peter F. 
Published: March 2009

Background
The authors tested the hypotheses that, compared with an overnight continuous femoral nerve block (cFNB), a 4-day ambulatory cFNB increases ambulation distance and decreases the time until three specific readiness-for-discharge criteria are met after tricompartment total knee arthroplasty.

Methods
Preoperatively, all patients received a cFNB (n = 50) and perineural ropivacaine 0.2% from surgery until the following morning, at which time they were randomly assigned to either continue perineural ropivacaine or switch to perineural normal saline. Primary endpoints included (1) time to attain three discharge criteria (adequate analgesia, independence from intravenous analgesics, and ambulation of at least 30 m) and (2) ambulatory distance in 6 min the afternoon after surgery. Patients were discharged with their cFNB and a portable infusion pump, and catheters were removed on postoperative day 4.

Results
Patients given 4 days of perineural ropivacaine attained all three discharge criteria in a median (25th-75th percentiles) of 25 (21-47) h, compared with 71 (46-89) h for those of the control group (estimated ratio, 0.47; 95% confidence interval, 0.32-0.67; P <0.001). Patients assigned to receive ropivacaine ambulated a median of 32 (17-47) m the afternoon after surgery, compared with 26 (13-35) m for those receiving normal saline (estimated ratio, 1.21; 95% confidence interval, 0.71-1.85; P = 0.42).

Conclusions
Compared with an overnight cFNB, a 4-day ambulatory cFNB decreases the time to reach three important discharge criteria by an estimated 53% after tricompartment total knee arthroplasty. However, the extended infusion did not increase ambulation distance the afternoon after surgery. (ClinicalTrials.gov No. NCT00135889.).
Success of Tracheal Intubation with Intubating Laryngeal Mask Airways
Authors: Liu Eugene H. , Goy Raymond W. , Lim Yvonne , Chen Fun-Gee 
Published: March 2009

Background
The LMA CTrach system (The Laryngeal Mask Company, Singapore) is a development of the LMA Fastrach system (The Laryngeal Mask Company, Singapore), with integrated fiberoptic bundles and a detachable liquid crystal display viewer. This randomized study of 271 patients compared tracheal intubation with these two systems.

Methods
In both groups, ventilation was optimized after insertion of the laryngeal mask conduit before proceeding further: intubation with the LMA Fastrach, and optimizing the conduit placement and view and then intubation with the LMA CTrach. The first-attempt and overall success rates of tracheal intubation, and the times required, were recorded.

Results
Tracheal intubation was successful on the first attempt in 93.3% of patients with the LMA CTrach and 67.9% of patients with the LMA Fastrach (P < 0.001). The success rates within three attempts were 100% with the LMA CTrach and 96.4% with the LMA Fastrach (P = 0.06). The median (interquartile range) time for the complete tracheal intubation process was 116 (82-156) s with the LMA CTrachand 100 (74-121) s with the LMA Fastrach (P = 0.002). There was no correlation between the grade of conventional laryngoscopy and success of intubation with either system.

Conclusions
The ability to view the glottis and optimize placement of the LMA CTrach under vision enabled a higher first-attempt success rate of tracheal intubation with the LMA CTrach. However, more time is required with the LMA CTrach, there are failed views in some patients, and its cost effectiveness remains unclear.
Remifentanil Inhibits Rapid Eye Movement Sleep but Not the Nocturnal Melatonin Surge in Humans
Authors: Bonafide Christopher P. , Aucutt-Walter Natalie , Divittore Nicole , King Tonya , Bixler Edward O. , Cronin Arthur J. 
Published: March 2009

Background
Postoperative patients are sleep deprived. Opioids, commonly administered for postoperative pain control, are often mistakenly considered inducers of naturally occurring sleep. This study describes the effect of the opioid remifentanil on nocturnal sleep in healthy volunteers. In addition, this study tests the hypothesis that opioid-induced sleep disturbance is caused by a circadian pacemaker disturbance, reflected by suppressed nocturnal plasma concentration of melatonin.

Methods
Polysomnography was performed in 10 volunteers from 11:00 pm to 7:00 am for four nights at 6-day intervals. On two nights, remifentanil (0.01-0.04 microg x kg x min) was infused from 10:30 pm to 7:00 am, and either a placebo capsule or 3.0 mg melatonin was administered at 10:30 pm. On two additional nights, saline was infused, and the placebo or melatonin capsules were administered at 10:30 pm. Blood was drawn at 12:00 am, 3:00 am, and 6:00 am to measure the plasma concentration of melatonin and cortisol. A repeated-measures analysis of variance model was used to determine the effect of remifentanil on sleep stages, the effect of remifentanil on the plasma concentration of melatonin, and the effect of exogenous melatonin on remifentanil-induced sleep disturbance.

Results
Remifentanil inhibited rapid eye movement sleep (14.1 +/- 7.2% to 3.9 +/- 6.9%). The amount of slow wave sleep decreased from 6.8 +/- 7.6% to 3.2 +/- 6.1%, but this decrease was not statistically significant. Remifentanil did not decrease melatonin concentration. Melatonin administration did not prevent remifentanil-induced sleep disturbance.

Conclusions
An overnight constant infusion of remifentanil inhibits rapid eye movement sleep without suppressing the nocturnal melatonin surge.
Adverse Effects of Methylene Blue on the Central Nervous System
Authors: Vutskits Laszlo , Briner Adrian , Klauser Paul , Gascon Eduardo , Dayer Alexandre G. , Kiss Jozsef Z. , Muller Dominique , Licker Marc J. , Morel Denis R. 
Published: March 2009

Background
An increasing number of clinical observations suggest adverse neurologic outcome after methylene blue (MB) infusion in the setting of parathyroid surgery. Hence, the aim of the current study was to investigate the potentially neurotoxic effects of MB using a combination of in vivo and in vitro experimental approaches.

Methods
Isoflurane-anesthetized adult rats were used to evaluate the impact of a single bolus intravascular administration of MB on systemic hemodynamic responses and on the minimum alveolar concentration (MAC) of isoflurane using the tail clamp test. In vivo, MB-induced cell death was evaluated 24 h after MB administration using Fluoro-Jade B staining and activated caspase-3 immunohistochemistry. In vitro, neurotoxic effects of MB were examined in hippocampal slice cultures by measuring excitatory field potentials as well as propidium iodide incorporation after MB exposure. The impact of MB on dendritic arbor was evaluated in differentiated single cell neuronal cultures.

Results
Bolus injections of MB significantly reduced isoflurane MAC and initiated widespread neuronal apoptosis. Electrophysiologic recordings in hippocampal slices revealed a rapid suppression of evoked excitatory field potentials by MB, and this was associated with a dose-dependent effect of this drug on cell death. Dose-response experiments in single cell neuronal cultures revealed that a 2-h-long exposure to MB at non-cell-death-inducing concentrations could still induce significant retraction of dendritic arbor.

Conclusions
These results suggest that MB exerts neurotoxic effects on the central nervous system and raise questions regarding the safety of using this drug at high doses during parathyroid gland surgery.
Perioperative Use of Dobutamine in Cardiac Surgery and Adverse Cardiac Outcome
Authors: Fellahi Jean-Luc , Parienti Jean-Jacques , Hanouz Jean-Luc , Plaud Benoît , Riou Bruno , Ouattara Alexandre 
Published: March 2009

Background
Catecholamines, mainly dobutamine, are often administered without institutional guidelines or prespecified algorithms in cardiac surgery. The current study assessed the consequences on clinical outcome of catecholamines simply based on the clinical judgment of the anesthesiologists after cardiopulmonary bypass in adult cardiac surgery.

Methods
Consecutive patients were enrolled in a nonrandomized cohort study. Factors associated with perioperative use of catecholamines and with outcomes were recorded prospectively to conduct bias adjustment, including propensity scores. Major cardiac morbidity (i.e., ventricular arrhythmia, use of an intraaortic balloon pump and postoperative myocardial infarction) and all-cause intrahospital mortality were the primary and secondary endpoints, respectively. Results are expressed as odds ratio (OR) [95% confidence interval].

Results
During the study, 84 of 657 patients (13%) received catecholamines, most often dobutamine (76 of 84, 90%). A higher incidence of both major cardiac morbidity (30 vs. 9%; P < 0.001; OR, 4.2 [2.5-7.3]) and all-cause intrahospital mortality (8 vs. 1%; P < 0.001; OR, 12.9 [3.7-45.2]) was observed in the catecholamine group compared with the control group. After adjusting for channeling bias and confounding factors, catecholamine administration remained significantly associated with major cardiac morbidity after propensity score stratification (OR, 2.1 [1.0-4.4]; P < 0.05), propensity score covariance analysis (OR, 2.3 [1.0-5.0]; P < 0.05), marginal structural models (OR, 1.8 [1.3-2.5]; P < 0.001), and propensity score matching (OR, 3.0 [1.2-7.3]; P < 0.02), but not with all-cause intrahospital mortality.

Conclusions
These results suggest that dobutamine should only be administered when the benefit is judged to outweigh the risks.
Cardiac Surgery Fast-track Treatment in a Postanesthetic Care Unit
Authors: Ender Joerg , Borger Michael Andrew , Scholz Markus , Funkat Anne-Kathrin , Anwar Nadeem , Sommer Marcus , Mohr Friedrich Wilhelm , Fassl Jens 
Published: March 2009

Background
The authors compared the safety and efficacy of a newly developed fast-track concept at their center, including implementation of a direct admission postanesthetic care unit, to standard perioperative management.

Methods
All fast-track patients treated within the first 6 months of implementation of our direct admission postanesthetic care unit were matched via propensity scores and compared with a historical control group of patients who underwent cardiac surgery prior to fast-track implementation.

Results
A total of 421 fast-track patients were matched successfully to 421 control patients. The two groups of patients had a similar age (64 +/- 13 vs. 64 +/- 12 yr for fast-track vs. control, P = 0.45) and European System for Cardiac Operative Risk Evaluation-predicted risk of mortality (4.8 +/- 6.1% vs. 4.6 +/- 5.1%, P = 0.97). Fast-track patients had significantly shorter times to extubation (75 min [45-110] vs. 900 min [600-1140]), as well as shorter lengths of stay in the postanesthetic or intensive care unit (4 h [3.0-5] vs. 20 h [16-25]), intermediate care unit (21 h [17-39] vs. 26 h [19-49]), and hospital (10 days [8-12] vs. 11 days [9-14]) (expressed as median and interquartile range, all P < 0.01). Fast-track patients also had a lower risk of postoperative low cardiac output syndrome (0.5% vs. 2.9%, P < 0.05) and mortality (0.5% vs. 3.3%, P < 0.01).

Conclusion
The Leipzig fast-track protocol is a safe and effective method to manage cardiac surgery patients after a variety of operations.
Lack of Analgesia by Oral Standardized Cannabis Extract on Acute Inflammatory Pain and Hyperalgesia in Volunteers
Authors: Kraft Birgit , Frickey Nathalie A. , Kaufmann Rainer M. , Reif Marcus , Frey Richard , Gustorff Burkhard , Kress Hans G. 
Published: March 2009

Background
Cannabinoid-induced analgesia was shown in animal studies of acute inflammatory and neuropathic pain. In humans, controlled clinical trials with Delta-tetrahydrocannabinol or other cannabinoids demonstrated analgesic efficacy in chronic pain syndromes, whereas the data in acute pain were less conclusive. Therefore, the aim of this study was to investigate the effects of oral cannabis extract in two different human models of acute inflammatory pain and hyperalgesia.

Methods
The authors conducted a double-blind, crossover study in 18 healthy female volunteers. Capsules containing Delta-tetrahydrocannabinol-standardized cannabis extract or active placebo were orally administered. A circular sunburn spot was induced at one upper leg. Heat and electrical pain thresholds were determined at the erythema, the area of secondary hyperalgesia, and the contralateral leg. Intradermal capsaicin-evoked pain and areas of flare and secondary hyperalgesia were measured. Primary outcome parameters were heat pain thresholds in the sunburn erythema and the capsaicin-evoked area of secondary hyperalgesia. Secondary measures were electrical pain thresholds, sunburn-induced secondary hyperalgesia, and capsaicin-induced pain.

Results
Cannabis extract did not affect heat pain thresholds in the sunburn model. Electrical thresholds (250 Hz) were significantly lower compared with baseline and placebo. In the capsaicin model, the area of secondary hyperalgesia, flare, and spontaneous pain were not altered.

Conclusion
To conclude, no analgesic or antihyperalgesic activity of cannabis extract was found in the experiments. Moreover, the results even point to the development of a hyperalgesic state under cannabinoids. Together with previous data, the current results suggest that cannabinoids are not effective analgesics for the treatment of acute nociceptive pain in humans.
Influence of Methylenetetrahydrofolate Reductase Gene Polymorphisms on Homocysteine Concentrations after Nitrous Oxide Anesthesia
Authors: Nagele Peter , Zeugswetter Barbara , Wiener Caspar , Burger Hansjörg , Hüpfl Michael , Mittlböck Martina , Födinger Manuela 
Published: March 2009

Background
Mutations in the methylenetetrahydrofolate reductase (MTHFR) gene (677C>T, 1298A>C) cause elevated plasma homocysteine concentrations and have been linked to fatal outcomes after nitrous oxide anesthesia. This study tested the hypothesis that patients with common MTHFR 677C>T or 1298A>C mutations develop higher plasma homocysteine concentrations after nitrous oxide anesthesia than wild-type patients.

Methods
In this prospective, observational cohort study with blinded, mendelian randomization, the authors included 140 healthy patients undergoing elective surgery. All patients received 66% nitrous oxide for at least 2 h. The main outcome variable, plasma total homocysteine, and folate, vitamin B12, and holotranscobalamin II were measured before, during, and after surgery. After completion of the study, all patients were tested for their MTHFR 677C>T or 1298A>C genotype.

Results
Patients with a homozygous MTHFR 677C>T or 1298A>C mutation (n = 25) developed higher plasma homocysteine concentrations (median [interquartile range], 14.9 [10.0-26.4] microm) than wild-type or heterozygous patients (9.3 [7.5-15.5] microm; n = 115). The change in homocysteine after nitrous oxide anesthesia was tripled in homozygous patients compared with wild-type (5.6 microm [+60%] vs. 1.8 microm [+22%]). Only homozygous patients reached average homocysteine levels considered abnormal (> 15 microm). Plasma 5-methyl-tetrahydrofolate concentrations increased uniformly by 20% after nitrous oxide anesthesia, indicating the inactivation of methionine synthase and subsequent folate trapping. Holotranscobalamin II concentrations remained unchanged, indicating no effect of nitrous oxide on vitamin B12 plasma concentrations.

Conclusions
This study shows that patients with a homozygous MTHFR 677C>T or 1298A>C mutation are at a higher risk of developing abnormal plasma homocysteine concentrations after nitrous oxide anesthesia.