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PubMed1994

Use of total reflection X-ray fluorescence analysis in the life sciences.

Total Reflection X-ray Fluorescence Analysis (TXRF) is accepted as a powerful analytical tool. TXRF is basically an energy-dispersive technique with the sample excitated in total reflection geometry. Simultaneous detection of almost all chemical elements and lower limits of detection for medium Z elements in the range of a few hundred fg are achievable at optimized excitation conditions. Aqueous and acidic solutions are the preferred sample types, so a lot of applications in the life sciences are given. For solids and other samples, special preparation techniques are required.

Animals↗

PubMed1998

Central venous pressure from common iliac vein reflects right atrial pressure.

PURPOSE: To determine whether central venous pressure at the common iliac vein reflects right atrial pressure in adult patients. METHODS: In this prospective, non-blinded study 26 mechanically-ventilated adult patients were studied. Simultaneous pressure readings were obtained from the right atrium (TCVP) and the common iliac vein (ACVP). RESULTS: There was a correlation between TCVP and ACVP (r = 0.987; P < 0.0001). The mean difference between TCVP and ACVP was 0.93 mm Hg. And the limits of agreement were: -1.93 to 1.77 mm Hg. CONCLUSION: Venous pressure recorded from the common iliac vein reflects that in the right atrium. Adopting a femoral route for central venous pressure measurement may avoid some of the complications associated with the subclavian route.

Adolescent↗

PubMed1995

Does the initial distribution volume of glucose reflect plasma volume after haemorrhage in dogs?

To test the hypothesis that the initial distribution volume of glucose (IDVG) reflects plasma volume, the relationship between the IDVG and indocyanine green (ICG) assessments of plasma volume (Vd-ICG) were evaluated simultaneously both before and after induced haemorrhage (30 ml.kg-1) in eight mongrel dogs. The IDVG and the Vd-ICG were calculated with a one-compartment model from repeated measurements of plasma glucose three to seven minutes, and of plasma ICG three to nine minutes after simultaneous infusions of both glucose 100 mg.kg-1 and ICG 0.5 mg.kg-1. The IDVG calculated with a one-compartment model (IDVG-OCM) was also compared with a two-compartment model within 15 min (IDVG-TCM) on nine occasions among a total of 12 determinations. Using Bland and Altman analysis to compare the two analytical models, the IDVG-OCM tends to overestimate the IDVG-TCM by an average of 0.04 L. Although the IDVG-OCM was two to three times larger than the Vd-ICG at each corresponding point, a correlation was obtained between the IDVG-OCM and the Vd-ICG before and after induced haemorrhage (r = 0.85, n = 16, P < 0.001). We conclude that the IDVG reflects plasma volume in normal and hypovolaemic dogs, although the IDVG cannot be used directly to estimate plasma volume.

Animals↗

PubMed2000

Does central venous pressure reflect the circulating blood volume for the decrement of compliance just after esophagectomy?

This study investigates whether the pressure parameters obtained from the Swan-Ganz catheter (SGC) accurately reflect the circulating blood volume just after en bloc resection of the thoracic esophagus with regional lymph node dissection. It is well known that this operation induces severe hemodynamic changes and although the pressure parameters obtained from the SGC are an accepted means of monitoring circulating blood volume, we have often experienced a discrepancy between the SGC data and the clinical state. We examined the pressure parameters and diameter of the inferior vena cava (IVC) and left ventricle (LV), and the central venous compliance using SGC and echocardiography in ten patients who underwent esophagectomy for esophageal cancer. The central venous pressure, pulmonary arterial mean pressure, and pulmonary artery wedged pressure were significantly increased just after the operation compared with the preoperative levels, while the diameters of the IVC and LV decreased just after the operation. The compliances of the IVC decreased significantly just after the operation. The hemodynamic shift to the third space after esophagectomy induces decrement of the compliances of IVC. As the CVP does not always reflect the circulating blood volume, measuring the diameter of the IVC using echocardiography is extremely useful for monitoring circulating blood volume just after esophagectomy.

Blood Volume↗

PubMed1999

Current definitions of acute lung injury and the acute respiratory distress syndrome do not reflect their true severity and outcome.

BACKGROUND: Despite intensive research, there are no universally accepted clinical definitions for acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS). A recent joint American-European Consensus Conference on ARDS formally defined the difference between ALI and ARDS based on the degree of oxygenation impairment. However, this definition may not reflect the true prevalence, severity and prognosis of these syndromes. METHODS: During a 22-month period, 56 consecutive mechanically ventilated patients who met the American-European Consensus definition for ARDS [arterial oxygen tension/fractional inspired oxygen (PaO(2)/FIO(2) </= 200 mmHg regardless of the level of positive end-expiratory pressure (PEEP), bilateral pulmonary infiltrates, and no evidence of left heart failure] were admitted into the intensive care units (ICU) of the Hospital del Pino, Las Palmas, Spain, and prospectively studied. The diagnosis of ALI and ARDS was made by a PEEP-FIO(2) trial, 24 h after patients met the Consensus inclusion criteria. Patients were classified as having ALI(-24 h) if the PaO(2)/FIO(2) was > 150 mmHg with PEEP = 5 cmH(2)O, and ARDS(-24 h) if the PaO(2) /FIO(2) was </= 150 mmHg with PEEP >/= 5 cmH(2)O. RESULTS: Overall mortality was 43 % (24 of 56). However, 24 h after inclusion, PaO(2) response to PEEP 5 cmH(2)O allowed the separation of our patients into two different groups: 31 patients met our ALI(-24 h) criteria (PaO(2)/FIO(2) > 150 mmHg) and their mortality was 22.6 %; 25 patients met our ARDS(-24 h) criteria (PaO(2)/FIO(2) </= 150 mmHg) and their mortality was 68 % (p = 0.0016). The differences in the respiratory severity index during the first 24 h of inclusion, PaO(2)/FIO(2) ratio at baseline and at 24 h, maximum plateau airway pressure, maximum level of PEEP, and number of organ system failures during the ICU stay were statistically significant. CONCLUSIONS: Since the use of PEEP in the American-European Consensus criteria for ARDS is not mandatory, that definition does not reflect the true severity of lung damage and outcome. Our data support the need for guidelines based on a specific method of evaluating oxygenation status before the American-European Consensus definition is adopted.

Adolescent↗

PubMed2002

The distinction between eye and object motion is reflected by the motion-onset visual evoked potential.

Humans are able to distinguish eye movement-induced retinal image motion and physical object motion during smooth pursuit eye movements. We investigated the neurophysiological basis of this ability by comparing motion-onset visual evoked potentials (VEPs) to onset of: (1) physical object motion during fixation, (2) eye movement-induced retinal image motion, and (3) physical object motion during eye movements. Electro-oculographic (EOG) artifacts were removed and the influence of eye-movement quality was evaluated. Retinal image shift was of similar magnitude in all conditions (9 degrees /s) and elicited typical motion-onset VEPs, with N2 at occipital and P2 at central derivations. During smooth pursuit, physical object motion induced N2 and P2 of higher latencies than during fixation. In the absence of physical object motion, i.e., for exclusively eye movement-induced retinal image motion, the N2 amplitude was reduced. This is taken as evidence that the activity of detectors of physical object motion is reflected by a part of the N2 component. N2 also reflects eye movement-induced retinal image motion. It is concluded that headcentric motion detection and the detection of eye movement-induced retinal image motion is mediated by brain mechanisms with similar latencies and, within the resolution limits of VEPs, at similar locations.

Electroencephalography↗

PubMed2005

Evaluation and development of automatic two-dimensional measurements of histomorphometric parameters reflecting trabecular bone connectivity: correlations with dual-energy x-ray absorptiometry and quantitative ultrasound in human calcaneum.

In osteoporosis, bone fragility results from both bone loss and changes in trabecular microarchitecture, which can be quantified by bone histomorphometric parameters. Twenty human calcaneum were collected after necropsy. All measurements were performed at the same anatomical location. Bone histomorphometric parameters were measured on histological slides with an automatic image analyzer. The aims of our study were (1) to develop automatic measurements of four additional parameters reflecting trabecular network connectivity and complexity, i.e., trabecular bone pattern factor (TBPf), Euler number/tissue volume (Euler) according to the three definitions previously reported and to a fourth one established in the laboratory (Euler(strut.cavity)), marrow star volume, and interconnectivity index, and to determine their usefulness in microarchitecture characterization; and (2) to validate these parameters by evaluating their relationship with dual-energy X-ray absorptiometry and quantitative ultrasound (QUS) measurements performed on the same samples. The statistical analysis showed that TBPf and Euler(strut.cavity) appeared to be the most significant connectivity parameters, independently of bone quantity (bone mineral density, apparent density, cancellous bone volume). For QUS, after adjustment for bone quantity, only speed of sound (SOS) was significantly and negatively correlated to Euler(strut.cavity). Broadband ultrasound attenuation depends only on bone quantity. In conclusion, TBPf (a strut analysis parameter extrapolable in three dimensions) and Euler(strut.cavity) (the only bone connectivity parameter reflecting SOS) are two valid bone microarchitecture parameters. These new parameters were significantly correlated to the established trabecular structure parameters: trabecular thickness or trabecular spacing, being weakly correlated with SOS.

Absorptiometry, Photon↗

PubMed2006

Identification of the time-point which gives a plasma rabeprazole concentration that adequately reflects the area under the concentration-time curve.

OBJECTIVE: The purpose of this study is to evaluate whether a simple formula using limited blood samples can predict the area under the plasma rabeprazole concentration-time curve (AUC) in co-administration with CYP inhibitors. METHODS: A randomized double-blind placebo-controlled crossover study design in three phases was conducted at intervals of 2 weeks. Twenty-one healthy Japanese volunteers, including three CYP2C19 genotype groups, took a single oral 20-mg dose of rabeprazole after three 6-day pretreatments, i.e., clarithromycin 800 mg/day, fluvoxamine 50 mg/day, and placebo. Prediction formulas of the AUC were derived from pharmacokinetics data of 21 subjects in three phases using multiple linear regression analysis. Ten blood samples were collected over 24 h to calculate AUC. Plasma concentrations of rabeprazole was measured by an HPLC-assay (l.l.q.=1 ng/ml). RESULTS: The AUC was based on all the data sets (n=63). The linear regression using two points (C3 and C6) could predict AUC(0-infinity) precisely, irrespective of CYP2C19 genotypes and CYP inhibitors (AUC(0-infinity)=1.39xC3+7.17xC6+344.14, r (2)=0.825, p<0.001). CONCLUSION: The present study demonstrated that the AUC of rabeprazole can be estimated by the simple formula using two-point concentrations. This formula can be more accurate for the prediction of AUC estimation than that reflected by CYP2C19 genotypes without any determination, even if there are significant differences for the CYP2C19 genotypes. Therefore, this prediction formula might be useful to evaluate whether CYP2C19 genotypes really reflects the curative effect of rabeprazole.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2002

Lipid discrimination in phospholipid monolayers by the antimicrobial frog skin peptide PGLa. A synchrotron X-ray grazing incidence and reflectivity study.

We present a first study using synchrotron grazing incidence diffraction and X-ray reflectivity measurements on mixed phospholipid/peptide monolayers at the air/water interface. The thermodynamic properties of the pure and mixed monolayers were characterized using the classical film balance technique. Surface pressure/potential-area isotherms showed that the antimicrobial frog skin peptide PGLa formed a very stable monolayer with two PGLa molecules per kinetic unit and a collapse pressure of ~22 mN/m. X-ray grazing incidence diffraction indicated that the peptide-dimer formation did not lead to self-aggregation with subsequent crystallite formation. However, the scattering length density profiles derived from X-ray reflectivity measurements yield information on the PGLa monolayer that protrudes into the air phase by about 0.8 nm, suggesting that the peptide is aligned parallel to the air/water interface. The monolayers, composed of disaturated phosphatidylcholines or phosphatidylglycerols, were stable up to 60 mN/m and exhibited a first-order transition from a liquid-expanded to a liquid-condensed state around 10 mN/m. Structural details of the phospholipid monolayers in the presence and absence of PGLa were obtained from synchrotron experiments. Thereby, the X-ray data of distearoylphosphatidylcholine/PGLa can be analyzed by being composed of the individual components, while the peptide strongly perturbed the lipid acyl chain order of distearoylphosphatidylglycerol. These results are in agreement that PGLa mixes at a molecular level with negatively charged lipids, but forms separate islands in zwitterionic phosphatidylcholine monolayers and demonstrates that antimicrobial peptides can discriminate between the major phospholipid components of bacterial and mammalian cytoplasmic membranes.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed2005

Noninvasive vascular testing--a 35-year reflection.

Noninvasive vascular testing has made a major contribution to the care of vascular surgery patients. This article a reflection on a 35-year corroborative association with Doctor Norman Rich, during which many of the advances in noninvasive vascular testing have been witnessed and effected. I served my vascular surgery fellowship under Doctor Rich in 1967-68 at Walter Reed Army Hospital. The only noninvasive vascular equipment then was a pencil probe Doppler. The value of the Doppler in the management of peripheral vascular disease that year and in determining limb viability in combat surgery in Vietnam the following year was established, and both experiences were published. Later, Doctor Rich established the annual Military Vascular Surgery Meeting and was appointed as the first Chair of the Department of Surgery at the Uniformed Services University for Health Sciences (USU). I entered private practice in Central California in 1976, and ultrasonic imaging was developed which allowed noninvasive examination of the carotid arteries. I then developed a protocol to screen for the three silent, immediate causes of stroke, employing a "a quick carotid scan" for carotid artery disease, a lead II rhythm strip for atrial fibrillation, and blood pressure determination for hypertension so that these common causes of strokes could be recognized and treated, and potentially prevent the majority of strokes. My association with USU, Doctor Rich, and others involved proved instrumental in initiating implementation of stroke prevention screening. The structure established at USU provides a means of establishing the protocol nationally. Noninvasive vascular testing is an addition to Medical Science that has led to significant improvements in individual patient care and that has the potential of allowing a major reduction in death and disability from stroke and other vascular diseases. Throughout a 35-year collaborative association with Doctor Norman M. Rich, I have witnessed and developed many of these advances. These contributions to noninvasive vascular testing reflect the value of our collaboration.

History, 20th Century↗

PubMed2003

[Determination of the concentration distribution of macular pigment from reflection and fluorescence images].

OBJECTIVE: The macular pigment xanthophyll protects the macula in two ways: firstly, it absorbs hazardous blue light and secondly, it acts as a radical scavenger. A low concentration of xanthophyll may be regarded as a risk factor for age-related macular degeneration (AMD). Therefore, we investigated a simple method to determine the xanthophyll concentration at the fundus which is suitable for patient screening. METHOD: The local distribution of xanthophyll density was determined from monochromatic blue reflection images and autofluorescence images of the fundus in 18 healthy volunteers (mean age: 23.9 years). The significance of the parameters maximal, global, and mean concentration were compared. RESULTS: The maximal optical density of xanthophyll determined from reflection images was found to be 0.29+/-0.08 (mean for all test persons) which is in good agreement with literature data. The total xanthophyll concentration which is proportional to the maximal density, appeared to be appropriate to describe a person's overall xanthophyll status. Because of the low intensity of autofluorescence images, these are less useful for the determination of the xanthophyll concentration. CONCLUSIONS: Because of it's simplicity, the determination of xanthophyll concentration as described here can be performed by every ophthalmologist using a fundus camera and is, therefore, suitable as a screening method.

Adolescent↗

PubMed1997

[Measurements of ultrasound reflectivity of oculomotor muscles in endocrine orbitopathy].

BACKGROUND: In the course of Graves' disease (GD) the extraocular muscles become fibrotic after an acute inflammatory stage. Differentiation of these two stages is important for therapy. MATERIALS AND METHODS: First, we examined the eye muscles of 30 healthy volunteers with the 10 MHz-B probe (Ultrascan) Digital B 2000) and then those of 20 patients with GD. The thickness was measured in the longitudinal displayed muscle always with the same gain. The amplitude of the highest inner muscle spikes expressed as a percentage of amplitude of retina-sclera spike provided the internal reflectivity. The stage of GD was determined by clinical signs. RESULTS: In GD, thickness of inferior and medial rectus was significantly enhanced in both the inflammatory and fibrotic stages, while internal reflectivity was only significantly higher in the latter stage. CONCLUSIONS: Ultrasound discriminates the acute from chronic course of GD in eye muscles and thus provides a very useful tool for making therapeutic decisions.

Adult↗

PubMed2004

Serum hyaluronan as a marker reflecting the severity of cirrhosis and portal hypertension in postoperative biliary atresia.

The majority of patients with biliary atresia (BA) develop progressive liver disease and serious complications of portal hypertension, including esophageal varices and ascites, despite successful Kasai operation. The aim of this study was to evaluate whether serum hyaluronan (HA) reflects the severity of cirrhosis and its complications in patients with postoperative BA. Fifty-four postoperative BA patients aged 1 to 19 years were recruited into this study. Serum HA was determined by ELISA-based assay, and serum HA levels were compared among groups of patients according to Child's classification as well as the presence of esophageal varices and ascites. Mean serum HA concentration was significantly increased in patients with Child C (534.35 +/- 573.02 ng/ml) in comparison to patients with Child B (97.67 +/- 104.22 ng/ml, p = 0.002) and Child A (36.27 +/- 71.41 ng/ml, p < 0.001). Mean serum HA concentration was also significantly higher in patients who had ascites or esophageal varices than in those who did not suffer from these complications. Furthermore, patients who had variceal hemorrhage had significantly higher mean serum HA levels than those without bleeding. Thus, serum HA levels may reflect the severity of cirrhosis and its complications, and may be useful in monitoring the clinical outcomes of patients with postoperative BA.

Adolescent↗

PubMed2005

Increased cytokine transcripts in pouchitis reflect the degree of inflammation but not the underlying entity.

BACKGROUND AND AIMS: After ileopouch anal anastomosis (IPAA), 10-40% of patients with ulcerative colitis (UC) but only 5% of patients with familial adenomatous polyposis (FAP) develop pouchitis. Immunoregulatory abnormalities might be of importance in the pathogenesis of the disease. Therefore, we characterized cytokine and chemokine transcripts in inflamed and non-inflamed pouches in patients with UC compared to those with FAP and Crohn's disease (CD). PATIENTS AND METHODS: Mucosal biopsies were taken from 87 patients with IPAA [UC (n=70), CD (n=8) or FAP (n=9)]. Patients with active ileal CD (n=14), active UC (n=17) and non-inflammatory conditions (n=12) served as controls. The expression of 20 gene transcripts was quantified using real-time polymerase chain reaction. RESULTS AND FINDINGS: Pro-inflammatory cytokines and chemokines are significantly increased in IPAA patients with acute pouchitis. This increase is independent of the underlying disease (UC or CD) and reflects the degree of inflammation. A good correlation between pouchitis activity (using the Pouchitis Disease Activity Index) and the MRP-14, interleukin-8, macrophage inflammatory protein-2alpha and matrix metalloproteinase-1 transcripts was observed. INTERPRETATIONS AND CONCLUSIONS: Our data support the view that pouchitis reflects an inflammatory process that is different from that of underlying inflammatory bowel diseases, as the cytokine and chemokine patterns in pouchitis are neither typical of CD nor of UC, but maybe due to bacterial intestinal microflora overgrowth in the pouch lumen. Quantification of transcript levels allows an estimation of the extent of mucosal inflammation and may become helpful in the evaluation of the disease, especially in clinical trials.

Adolescent↗

PubMed1997

Enhanced resolution of specific chromosome and nuclear regions by reflectance laser scanning confocal microscopy.

DNA sequences digested by HaeIII and reconstructed by in situ nick translation employing digoxigenin-labelled nucleotides are usually revealed either by horseradish peroxidase or FITC fluorescence. To obtain a significant improvement in terms of resolution, sensitivity and specificity, colloidal gold has been used instead of FITC (as the reporter molecule) to reveal the labelled DNA. Colloidal gold and propidium iodide were visualised by employing the reflectance mode and the 488-nm laser line of a confocal laser scanning microscope. In chromosomes, the fluorescent reaction pattern showed diffuse areas of labelling in which it was impossible to identify any specific kind of banding along the arms. In some chromosomes and, in particular, 1 and 9, a C-negative banding due to the negativity of the centromeric areas was seen. A more accurate localisation on chromosomes, including telomeric regions, often organised in spot pairs that resembled an R-like banding, was detected using 1-nm colloidal gold. A fine labelling was also demonstrated in nuclei, especially at their peripheral heterochromatin. The non-fading properties of colloidal gold combined with visualisation by reflectance confocal laser scanning microscopy demonstrated the possibility of obtaining a higher spatial resolution than when using conventional fluorophores or higher laser wavelength. This improved way to study the localization of HaeIII digestion sites in single chromosomes and in interphase nuclei made the reaction a valuable tool for the detection of antigens or of specific DNA sequences in biological preparations.

Cell Nucleus↗

PubMedDate not supplied

Do the kinetics of peripheral muscle oxygenation reflect systemic oxygen intake?

To examine whether the kinetics of local muscle oxygenation reflect systemic oxygen intake, we measured the kinetics of local muscle oxygenation and systemic oxygen consumption (VO2). This study included 16 healthy males who performed an exercise tolerance test on a bicycle ergometer. During the exercise test, expiratory gas analysis was performed with an expiratory gas analyzer, and the kinetics of vastus lateralis muscle oxygenation were determined by near-infrared spectroscopy (NIRS). Oxygenated hemoglobin (OxyHb) and tissue blood oxygen saturation (StO2) gradually decreased during the exercise test, while deoxygenated hemoglobin (DeoxyHb) gradually increased. We examined correlations between the mean values of these parameters, which were calculated by time-integrating the values obtained using NIRS and dividing them by the integral time, and VO2. There was a marked positive correlation between DeoxyHb and VO2 (r = 0.893-0.986), and a marked negative correlation between StO2 and VO2 (r = 0.859-0.995). There was a negative correlation between VO2 and OxyHb (r = 0.726-0.978), and no correlation between TotalHb and VO2. These results suggest that the kinetics of peripheral muscle oxygenation reflect systemic VO2.

Adult↗

PubMed2001

Changes in p(i)CO(2) reflect splanchnic mucosal ischaemia more reliably than changes in pH(i) during haemorrhagic shock.

BACKGROUND: Gastric tonometry is intended to reveal alterations in splanchnic perfusion and oxygenation. Based on the tonometric measurement of gastric mucosal partial pressure of carbon dioxide (pCO(2)) and the simultaneous determination of arterial blood gas parameters (bicarbonate concentration [HCO(3-)], pH and pCO(2)), several parameters can be calculated. AIMS: To identify the most suitable tonometric parameter [gastric mucosal pH (pH(i)), intramucosal pCO(2) (p(i)CO(2)), the difference between tonometric and arterial pCO(2) concentrations (pCO(2) gap), [H+] gap] that reliably reflects gastric hypoperfusion and hypoxia during severe haemorrhagic shock. DESIGN: Randomised, controlled experimental study. METHODS: An artificial stenosis of the left anterior descending coronary artery (LAD) was induced. Subsequently, the animals were haemorrhaged to a mean arterial pressure of 45 mmHg, which was maintained for 60 min. MEASUREMENTS AND MAIN RESULTS: Tonometric measurements were performed in 17 land-race pigs before and after induction of LAD stenosis and after haemorrhagic shock. P values obtained using the Wilcoxon signed-rank testing were used to compare the level of significance for the tonometric parameters and the corresponding arterial blood gas values [arterial pCO2 (p(a)CO(2)), [HCO(3-)], arterial pH (pH(a))]. While induction of critical coronary stenosis did not provoke any changes, all parameters changed significantly during haemorrhagic shock. The lowest P value was found for pH(i) (P=0.00013) followed by [H+ gap] (P=0.0005). P values higher by a factor of ten were found for pCO(2) gap (P=0.00119) and were highest for p(i)CO(2) (P=0.00562). P values of the corresponding arterial blood gas parameters were lower by a factor of ten than the P value of p(i)CO(2). CONCLUSION: pH(i), pCO(2) gap and [H+] gap are considerably influenced by changes of systemic arterial blood gas values. This is demonstrated by lower P values of the corresponding arterial blood gas values in comparison with p(i)CO(2). Therefore pH(i), pCO(2) gap and [H+] gap seem to indicate more likely systemic changes, whereas p(i)CO(2) appears to reflect disturbances of regional gastric tissue perfusion and oxygenation more reliably than any other derived tonometric parameter.

Animals↗

PubMed2003

Tympanic temperature reflects intracranial temperature changes in humans.

The purpose of the study was to identify extracranial locations in which temperature changes in humans reflect those of intracranial temperature in a reliable and repeatable way. This was achieved by subjecting 14 non-anaesthetized patients after neurosurgery to face fanning while intracranial and extracranial temperatures were continuously measured. In all patients the cranium was closed and the group included both febrile and non-febrile as well as hyperthermic and normothermic patients. The patients' faces were fanned for 20-30 min, with a small fan at an air speed of 3.25 m s(-1). This gave intracranial temperature changes measured in the subdural space ( T(sd)) that were highly and significantly correlated ( r=0.91, P<0.05, n=14) with changes in tympanic temperatures ( T(ty)). A low, statistically insignificant correlation ( r=0.40, P>0.05, n=12) was found between T(sd) and oesophageal temperatures. In conclusion, intracranial temperature changes, induced by face fanning, were reliably reflected by the changes in T(ty).

Adult↗