Search results for "Trachea"

Verification of a commercial implementation of the Macro-Monte-Carlo electron dose calculation algorithm using the virtual accelerator approach.

2009

Abstract In this work, the accuracy of the implementation of the Macro Monte Carlo electron dose calculation algorithm into the radiation therapy treatment planning system Eclipse is evaluated. This implementation – called eMC – uses a particle source based on the Rotterdam Initial Phase-Space model. A three-dimensional comparison of eMC calculated dose to dose distributions resulting from full treatment head simulations with the Monte Carlo code package EGSnrc is performed using the ‘virtual accelerator’ approach. Calculated dose distributions are compared for a homogeneous tissue equivalent phantom and a water phantom with air and bone inhomogeneities. The performance of the eMC algorithm…

Adverse Events and Unsuccessful Intubation Attempts Are Frequent During Neonatal Nasotracheal Intubations.

2021

Background: Intubation of neonates is difficult and hazardous. Factors associated with procedure-related adverse events and unsuccessful intubation attempts are insufficiently evaluated, especially during neonatal nasotracheal intubations.Objective: Aim of this study was to determine the frequency of tracheal intubation–associated events (TIAEs) during neonatal nasotracheal intubations and to identify factors associated with TIAEs and unsuccessful intubation attempts in our neonatal unit.Methods: This was a prospective, single-site, observational study from May 2017 to November 2019, performed at a tertiary care neonatal intensive care unit in a German academic teaching hospital. All endotr…

The influence of Ca2+ antagonists on the ciliary activity of the guinea pig trachea.

1990

The ciliary activity of the guinea pig tracheal respiratory epithelium was measured using a photoelectric device. Fourteen animals were administered 75 mg diltiazem/kg body weight 2 days, 1 day and 4 h prior to the investigation. Thirteen animals served as controls. In the pretreated group, the mean ciliary stroke frequency (13.4 +/- 3.0 Hz) was significantly lower (P = 0.02) than in the control group (16.6 +/- 3.7 Hz). The application of aerosolized 0.3 mmol/l nifedipine solution on the tracheal preparations of the control animals also significantly reduced the stroke frequency (P = 0.02). The ciliary activity never dropped beyond a frequency of about 8 Hz. The most probable interpretation…

Nasal high-flow preoxygenation for endotracheal intubation in the critically ill patient? Pro

2019

Endoscopic palliative management of esophageal and tracheal rupture

2014

The increasing number of patients requiring intensive care and airway support has led to a growing recognition that significant short- and long-term morbidity may be associated with the use of artificial airways; this is despite significant improvements in the materials used in laryngeal tubes, which aim to decrease the trauma associated with long-term intubation. We present the first case, to our knowledge,of huge, nontraumatic, esophageal perforation, widely communicating with the trachea, and which was treated successfully with double endoscopic stent placement.

Update on perioperative management of the child with asthma

2012

Asthma represents the leading cause of morbidity from a chronic disease among children. Dealing with this disease during the perioperative period of pediatric surgical procedures is, therefore, quite common for the anesthesiologist and other professionalities involved. Preoperative assessment has a key role in detecting children at increased risk of perioperative respiratory complications. For children without an optimal control of symptoms or with a recent respiratory tract infection elective surgery should be postponed, if possible, after the optimization of therapy. According to clinical setting, loco-regional anesthesia represents the desirable option since it allows to avoid airway ins…

Rolipram inhibits airway microvascular leakage induced by platelet-activating factor, histamine and bradykinin in guinea-pigs.

1993

Abstract Rolipram (0·1–1000 μg kg−1, i.v.) reduced the increase in microvascular permeability induced by platelet-activating factor (PAF; 50 ng kg−1, i.v.) at different sites of the guinea-pig airways. Rolipram (1–100μg kg−1, i.v.) inhibited histamine (30μg kg−1, i.v.)-and bradykinin (0·3 μg kg, i.v.)-induced airway microvascular leakage. These effects of rolipram were obtained at doses which inhibit histamine (7–20 μg kg−1 min−1)-induced bronchoconstriction (IC50 = 3 ± 1 μg kg, i.v.) without depressing arterial blood pressure in the guinea-pig. Aminophylline (50 mg kg−1) did not change the effect of PAF. The anti-exudative effect of rolipram is of potential therapeutic value in asthma.

Epithelium-derived inhibition of [3H]acetylcholine release from the isolated guinea-pig trachea

1990

To investigate presynaptic, regulatory mechanisms on parasympathetic nerve fibres innervating the airways, the release of newly-synthesized [3H]acetylcholine from the isolated trachea was studied. Reverse phase HPLC followed by liquid scintillation spectrometry was used to separate and quantify the radioactive compounds choline, phosphorylcholine and acetylcholine in the incubation medium and the tissue. During the incubation of the tracheae with [3H]choline a significant synthesis of [3H]acetylcholine (35,000 dpm/preparation) and [3H]phosphorylcholine (500,000 dpm/preparation) occurred. In epithelium-deficient tracheae the formation of [3H]phosphorylcholine was enhanced, whereas the conten…

Current Strategies for Tracheal Replacement: A Review

2021

Airway cancers have been increasing in recent years. Tracheal resection is commonly performed during surgery and is burdened from post-operative complications severely affecting quality of life. Tracheal resection is usually carried out in primary tracheal tumors or other neoplasms of the neck region. Regenerative medicine for tracheal replacement using bio-prosthesis is under current research. In recent years, attempts were made to replace and transplant human cadaver trachea. An effective vascular supply is fundamental for a successful tracheal transplantation. The use of biological scaffolds derived from decellularized tissues has the advantage of a three-dimensional structure based on t…

Characterization of endogenous noradrenaline release from intact and epithelium-denuded rat isolated trachea.

1991

1. Overflow of endogenous noradrenaline (NA) from the in vitro incubated rat trachea evoked by two periods of electrical field stimulation (S1, S2 at 3 or 15 Hz) or by high potassium (60 mM) was determined by high performance liquid chromatography (h.p.l.c.) with electrochemical detection. 2. In the presence of the neuronal uptake inhibitor desipramine, the alpha 2-adrenoceptor antagonist, yohimbine, enhanced the overflow of NA evoked by stimulation at 3 Hz by about 100% suggesting the presence of presynaptic inhibitory autoreceptors on the sympathetic nerves innervating the trachea. 3. When desipramine and yohimbine were present throughout the experiments, the overflow of NA evoked by the …