Search results for "PNI"
showing 10 items of 159 documents
Effects of Fenoldopam on Intracranial Pressure and Hemodynamic Variables at Normal and Elevated Intracranial Pressure in Anesthetized Pigs
1994
Fenoldopam (FE), a dopamine DA1-receptor agonist, has been introduced for treatment of arterial hypertension and heart failure and for preservation of renal function. Vasodilators are generally assumed to affect all vascular beds including the cerebral circulation. We have evaluated effects of FE-induced (4 micrograms.kg-1.min-1) arterial hypotension on intracranial pressure (ICP) and intraocular pressure (IOP) under conditions of normal and increased intracranial elastance. ICP and IOP responses to hypertension were tested by infusion of angiotensin II (15 micrograms.kg-1.min-1), and the response to hypercapnia was tested by elimination and reintegration of soda lime canisters in the breat…
Regional anticoagulation with heparin of an extracorporeal CO2 removal circuit: a case report
2019
Abstract Background Extracorporeal carbon dioxide removal is an increasingly used respiratory support technique. As is true of all extracorporeal techniques, extracorporeal carbon dioxide removal needs proper anticoagulation. We report a case of a patient at risk of bleeding complications who was treated with extracorporeal carbon dioxide removal and anticoagulated with a regional technique. Case presentation A 56-year-old Caucasian man with a history of chronic obstructive pulmonary disease exacerbation required extracorporeal carbon dioxide removal for severe hypercapnia and acidosis despite mechanical ventilation. The extracorporeal circuit was anticoagulated using a regional heparin tec…
Dynamics of tumor oxygenation and red blood cell flux in response to inspiratory hyperoxia combined with different levels of inspiratory hypercapnia.
2002
Abstract Background and purpose : Increasing arterial oxygen partial pressure (pO 2 ) by breathing hyperoxic gases is an effective means of improving tumor oxygenation, although the efficacy of adding CO 2 to the inspiratory gas has been discussed controversially. This study aimed at analyzing the impact of different inspiratory CO 2 fractions on the time course of oxygenation and perfusion changes in experimental tumors during and after inspiratory hyperoxia. Material and methods : Perfusion and oxygenation of rat DS-sarcomas were studied during spontaneous breathing of pure oxygen or hyperoxic gas mixtures containing different CO 2 fractions (1, 2.5 or 5%). Red blood cell (RBC) flux was a…
Hypoxyradiotherapy: lack of experimental evidence for a preferential radioprotective effect on normal versus tumor tissue as shown by direct oxygenat…
1998
Abstract Aim : In order to investigate possible pathophysiological mechanisms underlying the postulated preferential protective effect of hypoxia on normal tissue during radiotherapy, the impact of acute respiratory hypoxia (8.2% O 2 + 91.8% N 2 ) on tissue oxygenation was assessed. Methods : Tumor and normal tissue oxygenation was directly determined using O 2 -sensitive electrodes in two experimental rat tumors (DS and Yoshida sarcomas) and in the normal subcutis of the hind foot dorsum. Results : During respiratory hypoxia, arterial blood O 2 tension (pO 2 ), oxyhemoglobin saturation and mean arterial blood pressure decreased. Changes in the arterial blood gas status were accompanied by …
Noninvasive Ventilatory Assistance During Exercise for Patients with Kyphoscoliosis
2007
The goal was to determine whether noninvasive ventilatory assistance (NIV) could facilitate exercise performance and benefit physiologic parameters for eight hypercapnic kyphoscoliosis patients using a cycloergometer for 6-min periods at a constant power (20 W). The exercise protocols were performed in random order while breathing unaided (spontaneous breathing test or SBT) and also while receiving NIV (NIV test or NIVT). The NIV was pressure support (15 cm H2O) plus positive end expiratory pressure (PEEP) (4 cm H2O) via a nasal mask. Of the compared parameters, heart rate was not significantly different, but acidosis (pH = 7.32 +/- 0.04 vs. 7.36 +/- 0.04), hypoxia (PaO2 = 61.5 +/- 15.9 vs.…
Initiation of high-frequency oscillatory ventilation and its effects upon cerebral circulation in pigs: an experimental study
2006
BACKGROUND: Current practice at high-frequency oscillatory ventilation (HFOV) initiation is a stepwise increase of the constant applied airway pressure to achieve lung recruitment. We hypothesized that HFOV would lead to more adverse cerebral haemodynamics than does pressure controlled ventilation (PCV) in the presence of experimental intracranial hypertension (IH) and acute lung injury (ALI) in pigs with similar mean airway pressure settings. METHODS: In 12 anesthetized pigs (24-27 kg) with IH and ALI, mean airway pressure (P(mean)) was increased (to 20, 25, 30 cm H(2)O every 30 min), either with HFOV or with PCV. The order of the two ventilatory modes (cross-over) was randomized. Mean art…
Perioperative Adverse Events in Obstructive Sleep Apnea and Use of Noninvasive Mechanical Ventilation: Key Topics and Clinical Implications
2016
Obstructive sleep apnea (OSA) is a common public health care problem and, yet, the perioperative management of OSA remains inadequate. Patients affected by this condition are prone to early postoperative complications, in part due to the negative effects of sedative, analgesic, and anesthetic agents on pharyngeal tone and arousal responses to hypoxia, hypercapnia, and obstruction. The use of opioids may also contribute to late adverse events, mainly by suppressing the rapid eye movement phase of sleep. As a result, preoperative screening of patients at high risk of OSA, as well as the implementation of a perioperative strategy to reduce the risk of complications, should lead to early periop…
Sevoflurane Impairs Cerebral Blood Flow Autoregulation in Rats: Reversal by Nonselective Nitric Oxide Synthase Inhibition
2005
UNLABELLED In this study, we investigated the effects of 1.0 and 2.0 minimum alveolar anesthetic concentration (MAC) sevoflurane on cerebral blood flow (CBF) autoregulation before and after nonselective inhibition of nitric oxide (NO) synthase in rats. Rats were randomly assigned as follows: Group 1 (n = 8): 1.0 MAC sevoflurane; Groups 2 and 3 (n = 8 per group): 2.0 MAC sevoflurane. Assessment of autoregulation within a mean arterial blood pressure range of 140-60 mm Hg was performed by graded hemorrhage before and after administration of l-arginine methyl ester (l-NAME, 30 mg/kg IV, Groups 1 and 2) or during hypocapnia (Group 3). In 10 additional animals, brain tissue NO(2)(-) concentratio…
Der Möbeltischler für das bürgerliche Wohnhaus in allen seinen Räumen
1876
Vorlagen zu Möbeln für Wohn-, Speise- und Schlafzimmer, Gesellschafts- und Arbeitszimmer, für Toilette, Garderobe, Vorsaal, Comptoir, Küche, Garten u. s. w. in den modernsten und gangbarsten Formen : mit besonderer Rücksicht auf das bürgerliche Bedürfniß, wie auf leichte und billige Herstellung. Sechsunddreißig Folio-Tafeln.
Steric stabilization of modified nanoclays triggered by temperature.
2015
Halloysite clay nanotubes were modified through the adsorption of poly(N-isopropylacrylamide)-amine terminated (PNIPA-NH2) onto the external surface by exploiting electrostatic interactions at pH=6. In spite the amount of attached polymer is rather low (1 wt%), the properties of the nanotubes are deeply modified. The apparent specific volume and isentropic compressibilities of the hybrid nanomaterial dispersed in water evidenced the transferring of the termosensitive property from the polymer to halloysite. The hydrodynamic radius as well as the ζ-potential of the nanohybrid are consistent with the attachment of a positively charged polymer onto the negative surface of the nanotube. The col…