Abstract:
BACKGROUND:To determine whether temperature and haematocrit (Hct) alter the relationship between blood flow (BF) and blood flow velocity (BFV). METHODS:Using a transcranial Doppler apparatus, we measured the peak velocity of whole blood cells pumped by a cardiopulmonary bypass (CPB) circuit, through a 0.15-cm internal diameter segment of rigid tubing. BF and BFV relationships were obtained at temperatures of 19, 28, and 37 degrees C and at Hct of 0.05, 0.22, 0.39, and 0.54, by altering CPB flow over a range from 10 to 100 cc/min. Linear regression analysis was performed. RESULTS:The relationship between velocity and flow for the pooled Hct data was y=(0.43)x+0.86, r2=0.998 and 95% CI (0.999-1) whereas the association for the temperature data was y=(0.42)x+0.02, r2=0.9998 and 95% CI (0.999-0.9997). Changes of blood viscosity had no effect on velocity at a given flow rate. The combined effect of Hct and temperature on velocity for the relationship with flow is expressed by: y=1.3+2.4x. CONCLUSION:In fixed diameter vessels with laminar flow, the linear relationship between flow and velocity is not affected by changes in temperature and Hct in clinical ranges. These results are explained by the Fahraeus-Lindquist effect. They support the use of transcranial Doppler sonography to estimate cerebral blood flow in infants who may have large variations of Hct and/or temperature during bypass.
journal_name
Br J Anaesthjournal_title
British journal of anaesthesiaauthors
Paut O,Bissonnette Bdoi
10.1093/bja/88.2.277subject
Has Abstractpub_date
2002-02-01 00:00:00pages
277-9issue
2eissn
0007-0912issn
1471-6771pii
S0007-0912(17)36540-6journal_volume
88pub_type
杂志文章abstract::Using in vivo microdialysis, we have investigated the effects of propofol on acetylcholine (ACh) release from various regions of the rat brain. Propofol 25 and 50 mg kg-1 i.p. decreased basal ACh release from the frontal cortex by 70% and 85%, respectively. Propofol 25 and 50 mg kg-1 i.p. decreased basal ACh release f...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/80.5.644
更新日期:1998-05-01 00:00:00
abstract::Standard methods for accurate intraoperative measurement of neuromuscular block are either expensive or inconvenient and are not used widely. We have evaluated a new method of monitoring neuromuscular block using a low-frequency microphone. The method is based on the phenomenon of low-frequency sound emission by contr...
journal_title:British journal of anaesthesia
pub_type: 临床试验,杂志文章
doi:10.1093/bja/83.3.405
更新日期:1999-09-01 00:00:00
abstract::Cumulation and interaction of neuromuscular blocking effects of neomycin and tubocurarine were determined on responses of the tibialis anterior muscle of the anaesthetized cat to indirect stimulation. Neuromuscular block produced by neomycin was cumulative despite rapid and apparent full recovery of twitch tension and...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/53.6.571
更新日期:1981-06-01 00:00:00
abstract:BACKGROUND:Malposition of tracheostomy tubes is difficult to detect at the bedside and may contribute to eventual device misplacement. Endoscopic examination can be undertaken via tracheoscopic (T-view) or trans-laryngeal (L-view) approach, offering more precise detail regarding positioning within the airway. The aims ...
journal_title:British journal of anaesthesia
pub_type: 评论,信件
doi:10.1093/bja/aew336
更新日期:2017-01-01 00:00:00
abstract::A blood-gas study of the respiratory effects of sodium nitroprusside during anaesthesia has shown a marked reduction in PaO2 when the drug was administered. After nitroprusside PaO2 returned to the previous values. It is suggested that the reduction in PaO2 is a result of an increased scatter of ventilation/perfusion ...
journal_title:British journal of anaesthesia
pub_type: 临床试验,杂志文章
doi:10.1093/bja/47.11.1205
更新日期:1975-11-01 00:00:00
abstract::We have estimated the effect of omitting antagonism of neuromuscular block on postoperative nausea and vomiting. A systematic search (MEDLINE, EMBASE, Biological Abstracts, Cochrane library, reference lists and hand searching; no language restriction, up to March 1998) was performed for relevant randomized controlled ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,meta分析
doi:10.1093/bja/82.3.379
更新日期:1999-03-01 00:00:00
abstract::Although rare, spinal haematoma and abscess after central neuraxial blocks may cause severe permanent neurological injury. Optimal treatment and outcome remain unclear. In order to identify possible predisposing patient characteristics and describe the ensuing clinical course, we searched Medline, Embase, and the Coch...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,评审
doi:10.1016/j.bja.2017.11.105
更新日期:2018-04-01 00:00:00
abstract:Background:There is growing evidence that beta-blockade may reduce mortality in selected patients with sepsis. However, it is unclear if a pre-existing, chronic oral beta-blocker therapy should be continued or discontinued during the acute phase of severe sepsis and septic shock. Methods:The present secondary analysis...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/aex231
更新日期:2017-10-01 00:00:00
abstract::Volume loading with crystalloid solution results in more pronounced haemodilution in patients who develop arterial hypotension during induction of extradural anaesthesia than in those who remain normotensive. The aim of this study was to describe the time course of this increase in haemodilution. Heart rate, systolic ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/77.2.223
更新日期:1996-08-01 00:00:00
abstract::A new design of tracheal tube cuff was compared with two types of high-volume, low-pressure (HVLP) cuffed tracheal tube for leakage of fluid from the subglottic space into the trachea. Spontaneous and positive-pressure ventilation were simulated using a mechanical lung, an intubated model trachea and a ventilator. Exc...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/80.6.796
更新日期:1998-06-01 00:00:00
abstract:BACKGROUND:Dexmedetomidine (DEX) has been shown to provide good perioperative haemodynamic stability with decreased intraoperative opioid requirements. It may have neural protective effects, and thus may be a suitable anaesthetic adjuvant to neurosurgical anaesthesia. METHODS:Fifty-four patients scheduled for elective...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/ael220
更新日期:2006-11-01 00:00:00
abstract::The activity of the enzyme methionine synthase in fetal and maternal liver was investigated before and after exposure to nitrous oxide. Timed-pregnant rats on day 19 of gestation were exposed to either 10% or 50% nitrous oxide for various times up to 240 min. After exposure, fetal and maternal livers were removed and ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/56.5.523
更新日期:1984-05-01 00:00:00
abstract:BACKGROUND:A significantly increased risk of acute kidney injury (AKI) with the prophylactic use of aprotinin has been reported in adults undergoing cardiac surgery, but not in children. Blood product transfusions have also been shown to carry an independent risk of AKI. The present study assessed associations between ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/aes002
更新日期:2012-05-01 00:00:00
abstract:BACKGROUND:Balloon dilatational tracheostomy using the Ciaglia Blue Dolphin device has recently been introduced as a modification of the Ciaglia technique. The aim of this study was to compare the new Dolphin system with the single-step dilatational tracheostomy (Ciaglia Blue Rhino) in intensive care unit (ICU) patient...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aeq087
更新日期:2010-06-01 00:00:00
abstract::Mice, previously immunized with sheep erythrocytes, were anaesthetized with halothane and the splenic lymphoid cells were incubated with 3H-thymidine at 1-h intervals. Abiphasic response was observed; 0.9 and 1.5% halothane reduced 3H-thymidine incorporation into the primed lymphoid cells by 83 and 94% respectively, w...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/48.12.1129
更新日期:1976-12-01 00:00:00
abstract:BACKGROUND:Tapentadol is an analgesic agent for treatment of acute and chronic pain that activates the µ-opioid receptor combined with inhibition of neuronal norepinephrine reuptake. Both mechanisms are implicated in activation of descending inhibitory pain pathways. In this study, we investigated the influence of tape...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aeu056
更新日期:2014-07-01 00:00:00
abstract::The activity of a new i.v. anesthetic agent ICI 35 868, a compound unrelated to currently used barbiturate, eugenol or steroid agents, has been examined in a range of animal species. Some of the properties of ICI 35 868 resemble those of thiopentone in that it is a rapidly acting agent which produces anaesthesia of sh...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/52.8.731
更新日期:1980-08-01 00:00:00
abstract::The evidence for an association between hypertensive disease, elevated admission arterial pressure, and perioperative cardiac outcome is reviewed. A systematic review and meta-analysis of 30 observational studies demonstrated an odds ratio for the association between hypertensive disease and perioperative cardiac outc...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,meta分析,评审
doi:10.1093/bja/aeh091
更新日期:2004-04-01 00:00:00
abstract::We have compared the effects of dexmedetomidine and propofol on endocrine, metabolic, inflammatory and cardiovascular responses in patients in the intensive care unit (ICU) after major surgery. Twenty patients who were expected to require 8 h of post-operative sedation and ventilation were allocated randomly to receiv...
journal_title:British journal of anaesthesia
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1093/bja/86.5.650
更新日期:2001-05-01 00:00:00
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journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1016/j.bja.2019.07.030
更新日期:2019-12-01 00:00:00
abstract::We have studied the effect of analgesia on maternal temperature (oral and tympanic membrane) progression in 53 women during normal spontaneous labour. Three groups were studied: two received extradural analgesia with a continuous infusion of 0.25% bupivacaine with or without the addition of fentanyl; the third group r...
journal_title:British journal of anaesthesia
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1093/bja/67.5.565
更新日期:1991-11-01 00:00:00
abstract:Background:Cognitive aids improve the technical performance of individuals and teams dealing with high-stakes crises. Hand-held electronic cognitive aids have rarely been investigated. A randomized controlled trial was conducted to investigate the effects of a smartphone application, named MAX (for Medical Assistance e...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aex256
更新日期:2017-11-01 00:00:00
abstract:BACKGROUND:This study was undertaken to compare the effects of general anaesthesia (GA) and spinal anaesthesia (SA) on the need for postoperative hospitalization and early postoperative comfort in patients undergoing fast-track total knee arthroplasty (TKA). METHODS:One hundred and twenty subjects were randomly alloca...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aet104
更新日期:2013-09-01 00:00:00
abstract:BACKGROUND:We investigated the extent and frequency of dose errors and treatment delays made as a consequence of preparing drug infusions at the bedside, rather than using pre-filled syringes. METHODS:Forty-eight nurses with critical care experience volunteered to take part in this randomized, blinded, controlled stud...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aes257
更新日期:2012-11-01 00:00:00
abstract::The serum vasopressin (S-AVP) concentration, serum sodium concentration and osmolality, central venous pressure and fluid balance were measured during 10-min periods in 32 patients undergoing transurethral resection of the prostate. Concentration of S-AVP was unaffected by uncomplicated resection; irrigant absorption ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/63.3.330
更新日期:1989-09-01 00:00:00
abstract:BACKGROUND:The 15-item Quality of Recovery (QoR-15) scale is a validated patient-reported outcome questionnaire that measures the quality of postoperative recovery. This study aimed to validate a translated Korean version of QoR-15 (QoR-15K) in a broad range of surgical patients. METHODS:After Korean translation of th...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1016/j.bja.2020.06.040
更新日期:2020-10-01 00:00:00
abstract::The arterial to end-tidal PCO2 difference (PaCO2-PE'CO2) was measured in five anaesthetized dogs during controlled ventilation at 0.25 Hz (15 b.p.m.) and during high frequency jet ventilation at 1, 3 and 5 Hz. Because of the slow response of the infra-red carbon dioxide analyser, satisfactory recordings of end-tidal c...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/59.2.240
更新日期:1987-02-01 00:00:00
abstract:BACKGROUND:Arterial catheterization is painful and is associated with patient stress and anxiety. Analgesia is usually provided by subcutaneous injection of local anaesthetic. An alternative is topical anaesthesia, such as Rapydan which is a novel topical anaesthetic patch containing 70 mg each of lidocaine and tetraca...
journal_title:British journal of anaesthesia
pub_type: 杂志文章,随机对照试验
doi:10.1093/bja/aes254
更新日期:2012-11-01 00:00:00
abstract:BACKGROUND:Several medications have proved to be useful in preventing postoperative nausea and vomiting (PONV). However, routine antiemetic prophylaxis is not cost-effective. We evaluated the accuracy and discriminating power of an artificial neural network (ANN) to predict PONV. METHODS:We analysed data from 1086 in-...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/ael282
更新日期:2007-01-01 00:00:00
abstract:BACKGROUND:The perioperative period may be associated with a marked neurohumoral stress response, significant fluid losses, and varied fluid replacement regimes. Acute changes in serum sodium concentration are therefore common, but predictors and outcomes of these changes have not been investigated in a large surgical ...
journal_title:British journal of anaesthesia
pub_type: 杂志文章
doi:10.1093/bja/aeu409
更新日期:2015-04-01 00:00:00