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Oxygen Saturation (oxygen + saturation)
Kinds of Oxygen Saturation Terms modified by Oxygen Saturation Selected AbstractsMixed Venous Oxygen Saturation in the Diagnosis of Cardiac TamponadeJOURNAL OF CARDIAC SURGERY, Issue 2 2008David A. Fullerton M.D. No abstract is available for this article. [source] Effect of Oxygen Saturation in Water on Reproductive Performances of Pacu Piaractus brachypomusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2003Konrad Dabrowski Broodstock pacu Piaractus brachypomus as well as their eggs during their embryonic development were exposed to either normoxia (5.5,7.5 mg O2/L) or hypoxia (2.0,4.5 mg O2/L) conditions. The plasma concentrations of 11-ketotestosterone in males and estradiol-17, in females, as well as that of their precursor testosterone (T) were significantly (P < 0.01) higher in fish maintained under normoxic conditions than in fish exposed to hypoxia. After ovulation and spermiation induced by hormonal treatments, the plasma concentrations of T and 17,20,-dihydroxy-4-pregnen-3-one (17,20,P) significantly (P 0.05) increased in both sexes under both normoxic and hypoxic conditions. The plasma levels of T and 17,20,P achieved under normoxic conditions were higher than the ones recorded under hypoxia, except for those of 17,20,P in males. Males responded positively to the hormonal treatments, and the concentration of spermatozoa was 10.5 ± 0.8 109/mL under both oxygen conditions. Hypoxia resulted in significantly lower survival of embryos (17.3 ± 28%) in comparison to normoxic conditions (68.5 ± 25%). Moreover, larval deformities were found when exposed to hypoxia (91.6 ± 6%). During embryonic development of this species 4 mg/L of oxygen is tolerated at 26,27 C without negative impact. We conclude that despite the highly adaptable nature of adult pacu to environmental hypoxia, oxygen concentrations below 4 mg/L severely impacted survival of embryos. [source] Clinicopathologic Conference: A 28-year-old Woman with Perioral Cyanosis and Low Oxygen SaturationACADEMIC EMERGENCY MEDICINE, Issue 4 2008Jeffrey Sankoff MD Abstract The authors present a case of a 28-year-old woman on trimethoprim/sulfamethoxazole for 9 months, who presented to the emergency department with weakness, shortness of breath, and cyanosis. The patient's clinical course is outlined. A discussion of the potential etiologies, as well as the clinical management, is provided. [source] Comparison of desaturation and resaturation response times between transmission and reflectance pulse oximetersACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010S. J. CHOI Background: In general, there is a response time between actual arterial hypoxemia and its detection by pulse oximeters. We compared the desaturation and resaturation response times between two types of pulse oximeters, transmission and reflectance pulse oximeters, to find out which oximeter has a more rapid response time. Methods: Thirty-three ASA 1 or 2 patients were enrolled in this study. A transmission pulse oximeter was placed on the index finger and a reflectance pulse oximeter was placed on the forehead and monitored simultaneously. After the induction of general anesthesia without pre-oxygenation, we waited until the oxygen saturation value of any of two pulse oximeters declined to 90%, and then mask ventilation was started with 100% oxygen. Oxygen saturation was recorded at an interval of 2 s during this time. Results: The desaturation response time of SpO2 to 95% after apnea was 82.0 s (interquartile range: 67.0,98.5 s) vs. 94.0 s (interquartile range: 84.0,106.5 s) (P<0.001) and SpO2 to 90% was 94.0 s (interquartile range: 75.5,109.5 s) vs. 100.0 s (interquartile range: 84.5,114.5 s) (P<0.001) in the reflectance and transmission oximeters, respectively. The resaturation response time from mask ventilation to 100% SpO2 was 23.2±5.6 vs. 28.9±7.6 s (P<0.001) in the reflectance and transmission oximeters, respectively. Conclusion: In clinical situations in which rapid changes in oxygen saturation are expected, we recommend the forehead reflectance pulse oximeter because it responds more quickly in detecting oxygen desaturation and resaturation compared with the transmission pulse oximeter. [source] Influence of hypobaric hypoxia on bispectral index and spectral entropy in volunteersACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2009T. IKEDA Background: Hypoxia has been shown to change electroencephalogram parameters including frequency and amplitude, and may thus change bispectral index (BIS) and spectral entropy values. If hypoxia per se changes BIS and spectral entropy values, BIS and spectral entropy values may not correctly reflect the depth of anaesthesia during hypoxia. The aim of this study was to examine the changes in BIS and spectral entropy values during hypobaric hypoxia in volunteers. Methods: The study was conducted in a high-altitude chamber with 11 volunteers. After the subjects breathed 100% oxygen for 15 min at the ground level, the simulated altitude increased gradually to the 7620 m (25,000 ft) level while the subjects continued to breathe oxygen. Then, the subjects discontinued to breath oxygen and breathed room air at the 7620 m level for up to 5 min until they requested to stop hypoxic exposure. Oxygen saturation (SpO2), heart rate, 95% spectral edge frequency (SEF), BIS, response entropy (RE), and state entropy (SE) of spectral entropy were recorded throughout the study period. Results: Of the 11 subjects, seven subjects who underwent hypoxic exposure for 4 min were analysed. SpO2 decreased to 69% at the 7620 m level without oxygen. However, SEF, BIS, RE, and SE before and during hypoxic exposure were almost identical. Conclusion: These data suggest that hypoxia of oxygen saturation around 70% does not have a strong effect on BIS and spectral entropy. [source] Temperature-dependent changes in energy metabolism, intracellular pH and blood oxygen tension in the Atlantic codJOURNAL OF FISH BIOLOGY, Issue 6 2003F. J. Sartoris The effect of acute increase in temperature on oxygen partial pressure (Po2) was measured in the gill arches of Atlantic cod Gadus morhua between 10 and 19° C by use of oxygen microoptodes. Oxygen saturation of the gill blood under control conditions varied between 90 and 15% reflecting a variable percentage of arterial or venous blood in accordance with the position of each optode in the gill arch. The data obtained suggested that arterial Po2 remained more or less constant and arterial oxygen uptake did not become limiting during warming. A progressive drop in venous Po2, however, was observed at >10° C indicating that excessive oxygen uptake from the blood is not fully compensated for by circulatory performance, until finally, Po2 levels fully collapse. In a second set of experiments energy and acid,base status of white muscle of Atlantic cod in vivo was measured by magnetic resonance (31P-NMR) spectroscopy in unanaesthetized and unimmobilized fish in the temperature range between 13 and 21° C. A decrease in white muscle intracellular pH (pHi) with temperature occurred between 10 and 16° C (,pH per ° C = ,0·025 per ° C). In white muscle temperature changes had no influence on high-energy phosphates such as phosphocreatine (PCr) or ATP except during exposure to high critical temperatures (>16° C), indicating that white muscle energy status appears to be relatively insensitive to thermal stress if compared to the thermal sensitivity of the whole animal. The data were consistent with the hypothesis of an oxygen limitation of thermal tolerance in animals, which is set by limited capacity of oxygen supply mechanisms. In the case of Atlantic cod circulatory rather than ventilatory performance may be the first process to cause oxygen deficiency during heat stress. [source] Monitoring of pacemaker induced changes in cardiac output with inspired to endtidal oxygen difference in paediatric cardiac surgery patientsPEDIATRIC ANESTHESIA, Issue 2 2001Jan Bengtsson MD Methods:,Fourteen children aged 4,15 months were studied after corrective cardiac surgery. Heart rate was increased by 20% with an external pacemaker. Cardiac output (CO) was measured with thermodilution. Oxygen saturation was measured in systemic artery (SaO2), central vein (ScvcO2) and pulmonary artery (SvO2). Inspiratory to endtidal oxygen difference (FI - ETO2) was measured using a paramagnetic technique. SvO2 was measured continuously using a spectrophotometric technique. Results:,CO increased in three patients and decreased in 11 patients during pacing. Regression between ,CO and ,(1/Sa-vO2), ,(FI - ETO2/Sa-vO2), ,(FI - ETO2/Sa-cvcO2) showed r=0.70, r=0.76 and r=0.75, respectively. ,CO exceeded 10% in 17 of 26 interventions. Changes in FI - ETO2 of equal direction as changes in CO occurred in 12 of these 17 interventions. Conclusions:,Estimations of CO changes, based on SvO2, can be enhanced if changes in FI - ETO2 are also measured. ScvcO2 instead of SvO2 gives equivalent results. Sudden changes in FI - ETO2 after pacemaker initiation or termination can predict the direction of CO changes. [source] Clinic and radiological improvement of lipoid pneumonia with multiple bronchoalveolar lavagesPEDIATRIC PULMONOLOGY, Issue 4 2009Selma M.A. Sias MD Abstract Objective To assess the potential role of multiple bronchoalveolar lavages (BALs) in the treatment of children with lipoid pneumonia (LP). Materials and Methods This prospective study included 10 children (7 female, 3 male) with LP secondary to mineral oil aspiration. The age ranged from 3 months to 7 years and 1,60 days history of mineral oil intake, with a 6 months clinic follow-up. High-resolution computer tomography (CT) was performed 1,7 days prior to treatment and 2,20 days after the last therapeutic BAL, and reviewed by two experienced chest radiologists. Oxygen saturation was measured with digital oximetry. Therapeutic BAL was performed weekly until BAL fluid was nearly transparent and the cell count returned to normal range values. Results In all children, the initial CT scans showed multifocal bilateral consolidation involving mainly the dorsal and central regions. The areas of consolidation had foci of decreased attenuation in eight patients. Following a total of 4,10 therapeutic BALs, the CT scans returned to normal in 3 patients, improved considerably in 5, and showed only slight improvement in 2. Oxygen saturation increased from 88.8,±,3.4% at presentation to 96.2,±,0.8% after treatment (P,<,0.0001). Multiple lavages reduced (P,<,0.003) numbers of lipid-laden macrophages and restored BAL cellularity to normal range values. Conclusion Multiple therapeutic BAL of children with LP results in significant improvement of CT findings, oxygen saturation, restoration of BAL fluid cellularity and clinical recover without any evidence of respiratory distress at the end of treatment and 6 months after the last BAL. Pediatr Pulmonol. 2009; 44:309,315. © 2009 Wiley-Liss, Inc. [source] A comparison of the i-gelÔ with the LMA-UniqueÔ in non-paralysed anaesthetised adult patientsANAESTHESIA, Issue 10 2009H. Francksen Summary This study assessed two disposable devices; the newly developed supraglottic airway device i-gelÔ and the LMA-UniqueÔ in routine clinical practice. Eighty patients (ASA 1,3) undergoing minor routine gynaecologic surgery were randomly allocated to have an i-gel (n = 40) or LMA-Unique (n = 40) inserted. Oxygen saturation, end-tidal carbon dioxide, tidal volume and peak airway pressure were recorded, as well as time of insertion, airway leak pressure, postoperative sore-throat, dysphonia and dysphagia for each device. Time of insertion was comparable with the i-gel and LMA-Unique. There was no failure in the i-gel group and one failure in the LMA-Unique group. Ventilation and oxygenation were similar between devices. Mean airway pressure was comparable with both devices, whereas airway leak pressure was significantly higher (p < 0.0001) in the i-gel group (mean 29 cmH2O, range 24,40) compared with the LMA-Unique group (mean 18 cmH2O, range 6,30). Fibreoptic score of the position of the devices was significantly better in the i-gel group. Post-operative sore-throat and dysphagia were comparable with both devices. Both devices appeared to be simple alternatives to secure the airway. Significantly higher airway leak pressure suggests that the i-gel may be advantageous in this respect. [source] 2321: Retinal vessel diameter affects oxygen saturation measurementsACTA OPHTHALMOLOGICA, Issue 2010SH HARDARSON Purpose To test whether retinal vessel oxygen saturation measurements are affected by vessel diameter and to compare saturation between the temporal and nasal retina. Methods The Oxymap retinal oximeter is based on a fundus camera. It measures light absorbance at two wavelengths of light and calculates oxygen saturation in retinal vessels as well as vessel diameter. Measurements were performed on 12 healthy individuals. The effect of vessel diameter on saturation measurements was tested by measuring before and after the first bifurcation in the retina (1st degree parent vessels and 2nd degree daughter vessels). Arteriolar saturation can be assumed to be equal before and after bifurcation. Results The ratio between oxygen saturation in 1st degree parent arteriole and 2nd degree daughter arteriole was 0.97±0.02 (mean±SD). The ratio was significantly lower than the theoretical value of 1.00 (p<0.001, n=12) The corresponding ratio for venules was 0.90±0.04 (p<0.001). Oxygen saturation was 94±6% in 1st degree superotemporal arterioles and 99±6% in superonasal arterioles (p=0.057). Oxygen saturation in inferotemporal arterioles was 89±6% and 95±4% in inferonasal arterioles (p=0.009). There was no significant difference in venous saturation between temporal and nasal quadrants. Conclusion Measured oxygen saturation is lower in 1st degree parent vessels than in their 2nd degree daughter branches. This indicates that retinal vessel diameter affects oxygen saturation measurements. The higher measured saturation in the nasal arterioles, compared to temporal arterioles, may also be due to the fact that the nasal vessels are narrower. A correction for the effect of vessel diameter should be incorporated into oxygen saturation measurements. Commercial interest [source] 2324: Comparison of algorithms for oximetry in vivo and ex vivoACTA OPHTHALMOLOGICA, Issue 2010D DE BROUWERE Purpose Several authors have proposed a number of algorithms to extract the oxygen saturation in retinal blood vessels based on multispectral image analysis. We evaluated the outcomes of seven known algorithms based on hyperspectral retinal images. Methods Hyperspectral images are acquired using a fundus camera where a slit spectrograph is registered onto a retinal image. This combination compromises both accurate spatial and spectral information over the selected slit. Hyperspectral image analysis was used as input for the oximetry calculations described in the literature. We used a model eye to evaluate the different techniques in a controlled setup. Defibrinated horse blood was perfused through microtubules placed in front of a white (spectralon) background. Oxygen saturation was controlled by mixing different concentrations of sodium dithianate in the blood. Results Oxygen saturation was varied in five equidistant steps between 0 and 1. We correlated the outcomes to the metric of Harvey et al. [Biomed Optics 6631, 2007] Linear correlation with other algorithms resulted in r2 values between 0.881 and 0.985, however we observed a large discrepancy of the slope of each correlation line. The algorithms were also evaluated in images recorded in five healthy volunteers. In all techniques, veins could be separated from arteries by their reduces oxygen saturation, although values varied strongly between the different techniques. Conclusion Our findings confirm the working of a number of noninvasive retinal oximetry algorithms. Different readings can be can be attributed to an offset caused by an uncertainty of pigmentation and scattering parameters in the calibration procedure. [source] Serum and 24-hour Urine Analysis in Adult Cyanotic and Noncyanotic Congenital Heart Disease PatientsCONGENITAL HEART DISEASE, Issue 3 2009Efrén Martínez-Quintana MD ABSTRACT Introduction., Glomerulopathy is a complication of congenital heart disease patients. The risk of developing renal impairment is particularly high in cyanotic patients. Objective., The aim of this study was to determine the prevalence of renal dysfunction and microalbumiuria in adult cyanotic and non cyanotic congenital heart disease patients. Methods., Fourteen cyanotic and 22 noncyanotic congenital heart disease patients were studied in the Adult Congenital Heart Disease Unit at the Complejo Hospitalario Universitario Insular-Materno Infantil. Demographic characteristics, complete blood count, and 24-hour urianalysis were obtained, including abdominal ultrasound in those with cyanosis. Results., No differences were seen between age (years) (27.4 ± 8.2; 26.4 ± 8.3; P = .71), sex, size, weight, or glomerular filtration rate (mL/min/1.73 m2) (81.1 ± 22.9 vs. 84.9 ± 9.2, P = .482) between cyanotic and noncyanotic patients. However, Eisenmenger patients had significantly impaired renal function when compared with noncyanotic patients (73.0 ± 17.3 vs. 84.9 ± 9.2 mL/min/1.73 m2, P = .023). Significant differences were obtained in oxygen saturation (%) (83.8 ± 5.8 vs. 97.8 ± 0.8; P = .000), hematocrit (%) (59.3 ± 8.1 vs. 40.9 ± 8.5; P = .000), platelets (103/µL) (161.5 ± 70.5 vs. 277.9 ± 57.6; P = .000), serum uric acid (mg/dL) (7.5 ± 2.3 vs. 5.6 ± 1.5; P = .008) and microalbuminuria (mg/24 hours) (12.8 [0, 700.2] vs. 2.4 [0, 18.9]; P = .000) between cyanotic and noncyanotic patients. Five cyanotic patients (35.7%) had microalbuminuria (>30 mg/24 hours) and three of them (21.4%) proteinuria (>1 g/24 hours). No significant differences were seen between serum and urine parameters between cyanotic patients who had microalbuminuria (>30 mg/24 hours) and those cyanotic patients who did not have it (<30 mg/24 hours). Conclusions., Renal impairment is frequently seen in congenital heart disease patients, being associated occasionally with proteinuria and microalbuminuria in cyanotic ones. [source] Stent Dilatation of a Right Ventricle to Pulmonary Artery Conduit in a Postoperative Patient with Hypoplastic Left Heart SyndromeCONGENITAL HEART DISEASE, Issue 2 2008Rowan Walsh MD ABSTRACT A 10-day-old child with hypoplastic left heart syndrome (HLHS) underwent first-stage palliation for HLHS, Norwood procedure with a Sano modification, i.e., placement of a right ventricular to pulmonary artery (RV-PA) conduit. The patient developed progressively worsening systemic oxygen desaturation in the immediate postoperative period. Stenosis of the proximal RV-PA conduit was diagnosed by echocardiography. In the catheterization laboratory stent placement in the conduit was performed. This resulted in increased systemic oxygen saturation. The patient was eventually discharged from the hospital with adequate oxygen saturations. [source] Evaluation of Right Ventricular Fibrosis in Adult Congenital Heart Disease Using Gadolinium-enhanced Magnetic Resonance Imaging: Initial Experience in Patients with Right Ventricular Loading ConditionsCONGENITAL HEART DISEASE, Issue 5 2006Lopa P. Hartke MD ABSTRACT Objective., Gadolinium-enhanced cardiac magnetic resonance imaging has been used to show myocardial fibrosis, a finding that appears as late gadolinium enhancement. Its role in the evaluation of right ventricular fibrosis in congenital heart disease is unclear. The purpose of this study was to demonstrate late gadolinium enhancement of the right ventricle in adult and adolescent congenital heart disease and to investigate the relationship between this enhancement and clinical and pathophysiological data. Design., In total, 24 patients, 16 patients with congenital heart disease and right ventricular loading conditions and 8 controls, underwent gadolinium-enhanced viability imaging. Diagnoses varied and included repaired, palliated, and unrepaired lesions. The presence and extent of right ventricular late gadolinium enhancement was compared with patient clinical and hemodynamic data. Exact Wilcoxon tests, Fisher's exact tests, and Spearman's rank correlation were used to compare variables. Results., Nine of 16 patients (56%) were found to have right ventricular late gadolinium enhancement, ranging from 5% to 80% of right ventricular myocardium affected (mean 36.1%, SD 29.7). The combination of right ventricular systolic pressure ,98 mm Hg and systemic oxygen saturation ,93% strongly suggested the presence of right ventricular late gadolinium enhancement (positive predictive value 100%), but no single variable or combination of variables could reliably predict its absence (negative predictive values ,75%). Extent of right ventricular late gadolinium enhancement did not correlate with degree of either hypoxia or right ventricular hypertension. Conclusions., Gadolinium-enhanced cardiac magnetic resonance demonstrates right ventricular late gadolinium enhancement in some patients with congenital heart disease and right ventricular loading conditions. Clinical variables were associated with the presence of fibrosis but did not reliably predict severity. Myocardial preservation is likely a multifactorial process that may affect the right and left ventricles differently. [source] Blunted Hemodynamic Response and Reduced Oxygen Delivery With Exercise in Anemic Heart Failure Patients With Systolic DysfunctionCONGESTIVE HEART FAILURE, Issue 2 2007Jennifer Listerman MD Anemic heart failure patients with systolic dysfunction are known to have reduced exercise capacity. Whether this is related to poor hemodynamic adaptation to anemia is not known. Peak exercise oxygen consumption (VO2) and hemodynamics at rest and peak exercise were assessed among 209 patients and compared among those who were (n=90) and were not (n=119) anemic. Peak VO2 was significantly lower among anemic patients (11.7±3.3 mL/min/kg vs 13.4±3.1 mL/min/kg; P=.01). At rest, right atrial pressure was higher (10±5 mm Hg vs 8±4 mm Hg; P=.02) and venous oxygen saturation lower (62%±8% vs 58%±10%; P<.01) among anemic patients. At peak exercise, anemic patients had a higher wedge pressure (27±9 mm Hg vs 24±10 mm Hg; P=.04). No significant differences in stroke volume, cardiac index, systemic vascular resistance, or oxygen saturation were noted between the 2 groups. In conclusion, the relative hemodynamic response to exercise among anemic heart failure patients appears blunted and may contribute to worse exercise tolerance. [source] Circulatory effects of apnoea in elite breath-hold diversACTA PHYSIOLOGICA, Issue 1 2009F. Joulia Abstract Aim:, Voluntary apnoea induces several physiological adaptations, including bradycardia, arterial hypertension and redistribution of regional blood flows. Elite breath-hold divers (BHDs) are able to maintain very long apnoea, inducing severe hypoxaemia without brain injury or black-out. It has thus been hypothesized that they develop protection mechanisms against hypoxia, as well as a decrease in overall oxygen uptake. Methods:, To test this hypothesis, the apnoea response was studied in BHDs and non-divers (NDs) during static and dynamic apnoeas (SA, DA). Heart rate, arterial oxygen saturation (SaO2), and popliteal artery blood flow were recorded to investigate the oxygen-conserving effect of apnoea response, and the internal carotid artery blood flow was used to examine the mechanisms of cerebral protection. Results:, The bradycardia and peripheral vasoconstriction were accentuated in BHDs compared with NDs (P < 0.01), in association with a smaller SaO2 decrease (,2.7% vs. ,4.9% during SA, P < 0.01 and ,6% vs. ,11.3% during DA, P < 0.01). Greater increase in carotid artery blood flow was also measured during apnoea in BHDs than in controls. Conclusion:, These results confirm that elite divers present a potentiation of the well-known apnoea response in both SA and DA conditions. This response is associated with higher brain perfusion which may partly explain the high levels of world apnoea records. [source] Intravenous lidocaine for status epilepticus during childhoodDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2006Shin-ichiro Hamano MD; The clinical efficacy of lidocaine for convulsive status epilepticus in 53 convulsive episodes was examined in 37 children (17 males, 20 females). Mean age of patients receiving lidocaine was 3 years 7 months (SD 3y 5mo). Lidocaine administration achieved control of status epilepticus in 19 of 53 convulsive episodes (35.8%). Seizures ceased within 5 minutes of lidocaine administration in all 19 patients who were responsive to the drug. Regarding aetiology of status epilepticus and types of seizures, there was no statistical difference in effectiveness. Mild decrease of oxygen saturation, monitored by pulse oximetry, was observed in one patient, which improved by oxygenation using a mask. Lidocaine is a useful anticonvulsive agent; however, the response rate to lidocaine appears to be quite low, as less than half of the seizures were effectively controlled by lidocaine. Favourable properties of the drug include prompt responses, less alteration of consciousness, and fewer adverse effects, including less respiratory depression. [source] Abnormalities in cardiac and respiratory function observed during seizures in childhoodDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2005Mary E O'Regan MRCP MRCPCH The aim of this study was to observe any changes in cardiac and respiratory function that occur during seizures. Thirty-seven children (20 males, 17 females; median age 7y 6mo, range 1y 6mo to 15y 6mo) were studied. We recorded electroencephalograms, respiratory rate, heart rate, electrocardiograms, blood pressure, oxygen saturation, heart rate variability (time domain analysis), and cardiac vagal tone. A respiratory pause was defined as an interruption in respiration lasting more than 3s but less than 15s. Apnoea was defined as absence of respiration for more than 15s. Tachypnoea was defined as a 10% increase in respiratory rate from the pre-ictal baseline. Bradypnoea was defined as a 10% decrease in respiratory rate from the pre-ictal baseline. Significant hypoxia was defined as a saturation of less than 85%. A significant change in heart rate was taken as a 10% increase or decrease below the baseline rate. Data were obtained from 101 seizures: 40 focal seizures, 21 generalized seizures, and 40 absences. Focal seizures were frequently associated with significant respiratory abnormalities, tachypnoea in 56%, apnoea in 30%, frequent respiratory pauses in 70%, and significant hypoxaemia in 40%. The changes seen in respiratory rate were statistically significant. Changes in cardiac parameters, an increase or decrease in heart rate, were observed in only 26% of focal seizures and 48% of generalized seizures. We conclude that seizure activity can disrupt normal physiological regulation and control of respiratory and cardiac activity. [source] DEXMEDETOMIDINE FOR SEDATION DURING UPPER GASTROINTESTINAL ENDOSCOPYDIGESTIVE ENDOSCOPY, Issue 4 2008Kazutoshi Hashiguchi Background:, A clinical study was conducted to investigate the safety and efficacy of dexmedetomidine for sedation of patients undergoing routine upper gastrointestinal (GI) endoscopy. Methods:, Forty middle-aged patients who were admitted for medical examination were randomized to receive an initial loading dose infusion of dexmedetomidine 6.0 µg/kg per h over 10 min followed by a maintenance infusion of 0.6 µg/kg per h (group A) or rapid infusion of midazolam 0.05 mg/kg (group B) as sedation for routine endoscopy. Sixty patients did not receive sedative agent (group C). Assessment included measurement of heart rate (HR), blood pressure (BP), oxygen saturation, and endoscopy duration. Results:, There were no statistically significant differences among the groups in baseline characteristics. The level of sedation was similar between groups A and B, and the gag response score was significantly lower in the sedated groups than in group C. Hemodynamic stability was also demonstrated in group A during and after the endoscopic procedure. Increased systolic/diastolic BP was significantly attenuated in group A compared with group C. Interestingly, HR was significantly suppressed in group A than in groups B and C. In groups A and B, SpO2 was decreased compared with group C during and after the procedures; however, there was no significant difference between the two groups. There was no significant difference among the groups with endoscopy duration. Conclusions:, For sedation during upper endoscopy, dexmedetomidine is as safe and effective as midazolam, and it significantly reduces HR and BP during and after the endoscopic procedures. [source] EXAMINATION OF RESPIRATORY AND CIRCULATORY DYNAMICS DURING EXAMINATION USING A THIN GASTROINTESTINAL ENDOSCOPE IN ADVANCED-AGE SUBJECTSDIGESTIVE ENDOSCOPY, Issue 2 2007Miyako Niki Background:, Endoscopic examination influences cardiovascular hemodynamics. Upper gastrointestinal examinations are currently performed with a thin endoscope. In the present study, respiratory and circulatory dynamics and autonomic nervous activity using a thin endoscope (XP260) or a standard endoscope (XQ240) were investigated. Methods:, The subjects were 25 healthy adults aged less than 60 years (middle-aged group) and 15 healthy adults aged 60 years or older (advanced-age group). Percutaneous oxygen saturation, tonometric blood pressure, heart rate, and autonomic nervous activity were evaluated before the examination. After the endoscopic procedure, a questionnaire survey regarding examination-related stress was conducted. Results:, In the questionnaire survey, the proportion of subjects who answered ,very stress free' in the thin endoscope group was significantly higher than that in the standard endoscope group. The low frequency power of blood pressure variability (LFBP), an indicator of sympathetic nervous activity, was significantly lower during the thin endoscopic procedure than during the standard endoscopic procedure. Moreover, the ratio of low frequency power to high frequency power of heart rate variability (LFRR/HFRR), an indicator of sympathetic nervous activity, was significantly lower during thin endoscopic procedure than during the standard endoscopic procedure. The maximum rates of change in the LFBP and HFRR powers in the advanced-age group using thin and standard endoscopic procedures were significantly lower than in the middle-aged group. Conclusions:, The findings, although not in cross-over study, suggest that a thin endoscope has a less marked influence on circulatory kinetics. Gastrointestinal endoscopic examinations using a thin endoscope might reduce complications related to endoscopic screening examinations in advanced-age subjects. [source] Characteristics of Exercise-Induced Intrapulmonary Arteriovenous Fistula in Patients with Unexplained Exertional DyspneaECHOCARDIOGRAPHY, Issue 8 2010Stephanie J. Kelly B.S. Dynamic appearance of intrapulmonary arteriovenous fistula (AVF) during exercise may be associated with unexplained exertional dyspnea (UED) and can be diagnosed with an agitated saline contrast study during exercise echocardiography. However, the occurrence of AVF during exercise in patients with UED has not been well described. Thus, the frequency of exercise-induced intrapulmonary AVF in the outpatients with UED was retrospectively analyzed. Thirty-nine outpatients (age: 53 ± 12, 33 female) with UED underwent symptom-limited supine bicycle exercise echocardiography. Ten patients (26%) developed exercise-induced intrapulmonary AVF. Patients with and without AVF showed the similar peak exercise heart rate, systolic blood pressure, and rate-pressure product. The patients with AVF demonstrated a small but significant decrease in arterial oxygen saturation with exercise as compare to baseline (95.6 ± 2.8% at peak, vs. 97.5 ± 2.5% at baseline, P < 0.05 with a paired Student t -test). Our study suggests that exercise-induced intrapulmonary AVF is relatively common in the outpatients with UED and associated with mild exercise desaturation; however, the mechanism of desaturation could not be determined by this study. Further investigation to characterize and determine the clinical significance of AVF is warranted. (Echocardiography 2010;27:908-913) [source] Bispectral Electroencephalographic Analysis of Patients Undergoing Procedural Sedation in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 6 2003James R. Miner MD Abstract Objective: To determine whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction. Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS using propofol, methohexital, etomidate, and the combination of fentanyl and midazolam. Consenting patients were monitored by vital signs, pulse oximetry, nasal-sample end-tidal carbon dioxide (ETCO2), and BIS monitors during PS. Respiratory depression (RD) was defined as an oxygen saturation <90%, a change from baseline ETCO2 of >10 mm Hg, or an absent ETCO2 waveform at any time during the procedure. After the procedure, patients were asked to complete three 100-mm visual analog scales (VASs) concerning their perception of pain, recall of the procedure, and satisfaction with the procedure. Patients were divided into four groups based on the lowest BIS score recorded during the procedure, group 1, >85; group 2, 70,85; group 3, 60,69; group 4, <60. Rates of RD and VAS outcomes were compared between groups using chi-square statistics. Results: One hundred eight patients were enrolled in the study. No serious adverse events were noted. RD was seen in three of 14 (21.4%) of the patients in group 1, seven of 34 (20.6%) in group 2, 16 of 26 (61.5%) in group 3, and 18 of 34 (52.9%) in group 4. The rate of RD in patients in group 2 was not significantly different from that in group 1 (p = 0.46). The rate of RD in group 2 was significantly lower than that in groups 3 (p = 0.0003) and 4 (p = 0.006). For the VAS data, when group 1 was compared with the combined groups 2, 3, and 4, it had significantly higher rates of pain (p = 0.003) and recall (p = 0.001), and a dissatisfaction rate (p = 0.085) that approached significance. When groups 2, 3, and 4 were compared with chi-square test, there was not a significant difference in pain (p = 0.151), recall (p = 0.27), or satisfaction (p = 0.25). Conclusions: Patients with a lowest recorded BIS score between 70 and 85 had the same VAS outcomes as more deeply sedated patients and the same rate of RD as less deeply sedated patients. This range of scores represented the optimally sedated patients in this study. [source] Sleep staging and respiratory events in refractory epilepsy patients: Is there a first night effect?EPILEPSIA, Issue 12 2008Linda M. Selwa Summary Purpose:, We performed this analysis of possible first night effects (FNEs) on sleep and respiratory parameters in order to evaluate the need for two serial night polysomnograms (PSGs) to diagnose obstructive sleep apnea (OSA) in epilepsy patients. Methods:, As part of a pilot multicenter clinical trial investigating the effects of treating sleep apnea in epilepsy, two nights of PSG recording were performed for 40 patients with refractory epilepsy and OSA symptoms. Sleep architecture was examined in detail, along with respiratory parameters including apnea/hypopnea index (AHI) and minimum oxygen saturation. Analysis included two-tailed t -tests, Wilcox sign rank analysis, and Bland Altman measures of agreement. Results:, Total sleep time differed between the two nights (night 1,363.8 min + 59.4 vs. 386.3 min + 68.6, p = 0.05). Rapid eye movement (REM) sleep and percentage of REM sleep were increased during night two (night 1: 12.3% + 5.9 vs. night 2: 15.5% + 6.2, p = 0.007), and the total minutes of slow-wave sleep (SWS) were increased (night 1: 35.6 + 60.7 vs. night 2: 46.4 + 68.1, p = 0.01). No other sleep or respiratory variables differed between the two nights. Given an AHI inclusion criterion of five apneas per hour, the first PSG identified all but one patient with OSA. Discussion:, Respiratory parameters showed little variability between the first and second nights. Sleep architecture was mildly different between the first and second PSG night. Performing two consecutive baseline PSGs to diagnose OSA may not be routinely necessary in this population. [source] A Randomized Controlled Trial of Mist in the Acute Treatment of Moderate CroupACADEMIC EMERGENCY MEDICINE, Issue 9 2002Gina M. Neto MD Abstract Objective: To determine whether the use of mist improves clinical symptoms in children presenting to the emergency department (ED) with moderate croup. Methods: Children 3 months to 6 years of age were eligible for the study if they presented to the ED with moderate croup. Moderate croup was defined as a croup score of 2-7. The patients were randomly assigned to receive either mist (humidified oxygen) via mist stick or no mist. The patients had croup scores measured at baseline and every 30 minutes for up to two hours. At these intervals the following parameters were also measured: heart rate, respiratory rate, oxygen saturation, and patient comfort score. The patients were treated until the croup score was less than 2 or until two hours had elapsed. All patients initially received a dose of oral dexamethasone (0.6 mg/kg). Other treatments, such as racemic epinephrine or inhaled budesonide, were given at the discretion of the treating physician. The research assistants were unaware of the assigned treatments. Results: There were 71 patients enrolled in the study; 35 received mist and 36 received no mist. The two treatment groups had similar characteristics at baseline. The median baseline croup score was 4 in both groups. The outcomes were measured as the change from baseline at 30, 60, 90, and 120 minutes. The change in the croup score from baseline in the mist group was not statistically different from the croup score change in the group that did not receive mist (p = 0.39). There was also no significant difference in improvement of oxygen saturation, heart rate, or respiratory rate at any of the assessment times. There was no adverse effect from the mist therapy. Conclusions: Mist therapy is not effective in improving clinical symptoms in children presenting to the ED with moderate croup. [source] The influence of oxygen saturation on the distributional overlap of predator (cod, Gadus morhua) and prey (herring, Clupea harengus) in the Bornholm Basin of the Baltic SeaFISHERIES OCEANOGRAPHY, Issue 1 2002Stefan Neuenfeldt Environmental heterogeneity can create boundary conditions for the co-occurrence of marine predators and their prey. If one or both are spatially constrained by their tolerance to environmental variables, then spatial differences in the availability of possible habitats define the volume of distributional overlap. Cod (Gadus morhua L.) and its prey, herring (Clupea harengus L.), in the vertically stratified Bornholm Basin of the Baltic Sea are presented as an example. A non-linear model was used to estimate oxygen avoidance thresholds for both species. Herring avoided oxygen saturation levels below 50%, while cod tolerated oxygen saturation down to 16%. The threshold of 50% oxygen saturation, below which cod could not encounter its prey, herring, was applied to a time series of vertical oxygen profiles from the centre of the Bornholm Basin to estimate the size of the overlap volume during the winter period from 1958 to 1999. Dependent on the oxygenation of the deep-water, the overlap volume varied between 57 km3 and 250 km3. [source] Metalloproteinase-9 in circulating monocytes in pulmonary hypertensionFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 4 2006Caroline Cantini-Salignac Abstract The role of matrix metalloproteinases (MMPs) in pulmonary hypertension (PH) is complex as MMPs are involved in both the vascular and cardiac remodelling associated with PH. To gain insight into this problem, monocytes were isolated from pulmonary arterial blood in patients suffering from PH, related to chronic obstructive pulmonary disease (n = 6), chronic pulmonary thromboembolism (n = 3) or pulmonary arterial hypertension (n = 8). The severity of PH was associated with decreases in cardiac index (CI) and mixed venous blood oxygen saturation (SO2), and an increase in right atrial pressure (). Monocyte pro-MMP-9 content (zymography) was positively correlated with SO2 (r = 0.73, P < 0.05) and CI (r = 0.66, P < 0.05), and negatively with (r = 0.54, P < 0.05); there was no significant correlation with pulmonary vascular resistance. In conclusion, the pro-MMP-9 content of circulating monocytes was lower in the more severe forms of PH which showed heart failure suggesting that such MMP enzymatic activity reflects heart failure following pulmonary vascular and myocardial remodelling in PH. [source] Cardiovascular and Metabolic Effects of High-dose Insulin in a Porcine Septic Shock ModelACADEMIC EMERGENCY MEDICINE, Issue 4 2010Joel S. Holger MD Abstract Objectives:, High-dose insulin (HDI) has inotropic and vasodilatory properties in various clinical conditions associated with myocardial depression. The authors hypothesized that HDI will improve the myocardial depression produced by severe septic shock and have beneficial effects on metabolic parameters. In an animal model of severe septic shock, this study compared the effects of HDI treatment to normal saline (NS) resuscitation alone. Methods:, Ten pigs were randomized to an insulin (HDI) or NS group. All were anesthetized and instrumented to monitor cardiovascular function. In both arms, Escherichia coli endotoxin lipopolysaccharide (LPS) and NS infusions were begun. LPS was titrated to 20 ,g/kg/hour over 30 minutes and continued for 5 hours, and saline was infused at 20 mL/kg/hour throughout the protocol. Dextrose (50%) was infused to maintain glucose in the 60,150 mg/dL range, and potassium was infused to maintain a level greater than 2.8 mmol/L. At 60 minutes, the HDI group received an insulin infusion titrated from 2 to 10 units/kg/hour over 40 minutes and continued at that rate throughout the protocol. Survival, heart rate (HR), mean arterial pressure (MAP), pulmonary artery and central venous pressure, cardiac output, central venous oxygen saturation (SVO2), and lactate were monitored for 5 hours (three pigs each arm) or 7 hours (two pigs each arm) or until death. Cardiac index, systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), O2 delivery, and O2 consumption were derived from measured data. Outcomes from the repeated-measures analysis were modeled using a mixed-effects linear model that assumed normally distributed errors and a random effect at the subject level. Results:, No significant baseline differences existed between arms at time 0 or 60 minutes. Survival was 100% in the HDI arm and 60% in the NS arm. Cardiovascular variables were significantly better in the HDI arm: cardiac index (p < 0.001), SVR (p < 0.003), and PVR (p < 0.01). The metabolic parameters were also significantly better in the HDI arm: SVO2 (p < 0.01), O2 delivery (p < 0.001), and O2 consumption (p < 0.001). No differences in MAP, HR, or lactate were found. Conclusions:, In this animal model of endotoxemic-induced septic shock that results in severe myocardial depression, HDI is associated with improved cardiac function compared to NS resuscitation alone. HDI also demonstrated favorable metabolic, pulmonary, and peripheral vascular effects. Further studies may define a potential role for the use of HDI in the resuscitation of septic shock. ACADEMIC EMERGENCY MEDICINE 2010; 17:429,435 © 2010 by the Society for Academic Emergency Medicine [source] Processes governing river water quality identified by principal component analysisHYDROLOGICAL PROCESSES, Issue 16 2002I. Haag Abstract The present study demonstrates the usefulness of principal component analysis in condensing and interpreting multivariate time-series of water quality data. In a case study the water quality system of the lock-regulated part of the River Neckar (Germany) was analysed, with special emphasis on the oxygen budget. Pooled data of ten water quality parameters and discharge, which had been determined at six stations along a 200 km reach of the river between the years 1993 and 1998, were subjected to principal component analysis. The analysis yielded four stable principal components, explaining 72% of the total variance of the 11 parameters. The four components could be interpreted confidently in terms of underlying processes: biological activity, dilution by high discharge, seasonal effects and the influence of wastewater. From analysing the data of single stations separately, these processes were found to be active throughout the complete reach. Considering the oxygen budget of the river, the variance of biological activity, representing the counteracting processes of primary production and microbial degradation, was found to be most important. This principal component explained 79% of the observed variance of oxygen saturation. In contrast, the analysis of a reduced data set from the 1970s showed that oxygen saturation was then dominated by discharge and temperature variations. The findings indicate that the oxygen budget used to be governed directly by the emission of degradable matter, whereas nowadays eutrophication is most important for extreme oxygen concentrations. Therefore, controlling eutrophication has to be the primary goal, in order to mitigate the rare episodes of pronounced oxygen over- and undersaturation in the future. Copyright © 2002 John Wiley & Sons, Ltd. [source] Noncontact measurement of deep tissue absorption coefficient using Spatially Resolved Near-Infrared SpectroscopyIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 4 2007Masatsugu Niwayama Member Abstract We examined the influence of probe-tissue distance on the relationship between the deep tissue absorption coefficient and the spatial profile of light intensity by Monte Carlo simulation and in vivo experiments, using noncontact spatially resolved near-infrared spectroscopy (SRS). These results suggest that noncontact SRS can be reliably used for noncontact measurement of the absorption coefficient and oxygen saturation of deep tissues. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Value of fractional exhaled nitric oxide (FENO) for the diagnosis of pulmonary involvement due to inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 4 2010Ezgi Ozyilmaz MD Abstract Background: Pulmonary involvement due to inflammatory bowel disease (IBD) is frequent when evaluating a patient with IBD and pulmonary involvement remains complicated. Most of the patients are asymptomatic and the methods used are mostly invasive or expensive procedures. The aim of this prospective study is to evaluate the value of the fractional exhaled nitric oxide (FENO) level for the diagnosis of pulmonary involvement due to IBD and to investigate any correlation between FENO level and disease activity. Methods: Thirty-three nonsmoker patients with IBD (25 ulcerative colitis [UC] and 8 Crohn's Disease [CD]) who were free of corticosteroid treatment and 25 healthy subjects as a control group were enrolled in this study. All patients with IBD were investigated for pulmonary involvement with medical history, physical examination, chest roentgenogram, oxygen saturation, blood eosinophil levels, pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and FENO level. Results: Pulmonary involvement was established in 15 patients (45.5%) with IBD. The FENO level was higher in patients with pulmonary involvement than without pulmonary involvement and healthy controls independent from the pulmonary symptoms, eosinophil count, duration of disease, activity of disease, and surgery history (FENO: 32 ± 20; 24 ± 8; 14 ± 8 ppb, respectively) (P < 0.05). In addition, diffusion capacity (DLCO) was found to be significantly lower in patients with CD compared with UC (P < 0.05). Conclusions: This study showed that an increased FENO level may be used for identifying patients with IBD who need further pulmonary evaluation. Inflamm Bowel Dis 2009 [source] | ||||||||||||||||||||||||||||||||||||||||