Application Effect Analysis of Three Methods of Heating and Humidification for Weaning Patients in ICU

Objectives Adequate humidity and temperature of the inhaled mixed air are important for patients weaning from ventilators. It can not only prevent the damage of dry gas on respiratory tract, but also facilitate the discharge of sputum. We aim to investigate the humidification and heating effects of artificial nose, Venturi device plus thermostatic humidification T-tube (referred as VT), Venturi device plus thermostatic humidification T-tube and PEEP valve (referred as VTP) in critical ill patients with tracheotomy in ICU.Design:Retrospective cohort study.Setting: Tertiary academic medical center.Patients: A total of 166 patients were engaged in this study. Clinical and laboratory examination data were used to determine the heating and humidification performance of 3 different methods.Methods A retrospective, single-center cohort study was conducted in all critically ill patients ready to be weaned from mechanical ventilators. Three groups of patients were compared in terms of vital signs, the effect of artificial airway heating and humidification, and blood gas indicators. Basic patient data (age, gender, mechanical ventilation duration, ICU stay, disease type) were recorded. Vital signs include heart rate, blood pressure, respiratory rate, oxygen saturation; The performance of heating and humidifying the artificial airway were defined as the number of sputum suction and coughing within 24 hours, sputum characteristics, whether there is bloody sputum formation, whether there is phlegm callus formation; Blood gas indicators include pH, oxygen partial pressure, carbon dioxide partial pressure, lactic acid, residual base, and bicarbonate.Results In terms of the heating and humidification performance of patients in ICU, the VT method and the VTP method were significantly superior to those of artificial nasal method.SpO2 was significantly higher in patients treated with the VTP method than that in patients treated with VT.ConclusionCompared with the artificial nose method, the VTP method and VT methods are better. In terms of improving oxygenation, the VTP method could improve the patient's oxygen sum more than the VT mothod.

What is the “Status questionis” of the e-nose. The future of artificial nose

An artificial nose (e-nose) is a multipotential electronic device, based on various sensors with the ability to recognize different odours, in the same way that the human olfactory sense does. An updated e-nose system will allow us to detect different oncological and/or degenerative diseases of the human being that today are diagnosed late. Other options would include providing specific information on the quality and condition of food, analysing and detecting the degree of environmental pollution, analysing perfumes and their essences, determining the composition and characteristics of certain beverages such as wine, tea, oil, cocoa and other products. The application of new technologies, such as artificial intelligence and nanotechnology, make it easier to distinguish many different odours in less time. In this paper, we have made a current investigation of the different types of e-nose existing today. Aim of the study Currently nanotechnology, artificial intelligence and computer science are tools that have revolutionary possibilities for the construction of a new e-nose device and progress over the current scopes. If we manage to unite the advantages provided by each of these new technologies that we have mentioned, we will be able to build a very useful device applicable in various fields such as health, food and beverage industry, perfumes and environment. Therefore, the objectives we have in this study are the following: To learn where artificial nose technology stands and what has been developed so far. Based on these findings, ask ourselves the following question: Is it possible to achieve an effective functioning or is it an unreachable project? To compile the majority of scientific articles published mainly in the last 10 years with examples of the use that has been made of artificial noses in the measurement of volatile compounds in the different fields mentioned. In the same way to gather the information published in the last years in relation to the usefulness, existence in the market and purposes of equipment that can measure the olfaction in the human being, what we will call the Smell-o-meter or olfactometer for human use. Material and Methods In the first part of this research we will gather most of the information existing so far in the international bibliography, as well as the achievements and utilities obtained to date. Following we will analyse all the new concepts related to e-nose devices that exist on sensors, gas chromatography, nanotechnology application, electronic engineering, materials and techniques as preliminary ideas for the development of the devices.

Sniffing Bacteria with a Carbon-Dot Artificial Nose

Highlights Novel artificial nose based upon electrode-deposited carbon dots (C-dots). Significant selectivity and sensitivity determined by “polarity matching” between the C-dots and gas molecules. The C-dot artificial nose facilitates, for the first time, real-time, continuous monitoring of bacterial proliferation and discrimination among bacterial species, both between Gram-positive and Gram-negative bacteria and between specific strains. Machine learning algorithm furnishes excellent predictability both in the case of individual gases and for complex gas mixtures. Abstract Continuous, real-time monitoring and identification of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals. We introduce an artificial nose for sensing and distinguishing vapor molecules, based upon recording the capacitance of interdigitated electrodes (IDEs) coated with carbon dots (C-dots) exhibiting different polarities. Exposure of the C-dot-IDEs to volatile molecules induced rapid capacitance changes that were intimately dependent upon the polarities of both gas molecules and the electrode-deposited C-dots. We deciphered the mechanism of capacitance transformations, specifically substitution of electrode-adsorbed water by gas molecules, with concomitant changes in capacitance related to both the polarity and dielectric constants of the vapor molecules tested. The C-dot-IDE gas sensor exhibited excellent selectivity, aided by application of machine learning algorithms. The capacitive C-dot-IDE sensor was employed to continuously monitor microbial proliferation, discriminating among bacteria through detection of distinctive “volatile compound fingerprint” for each bacterial species. The C-dot-IDE platform is robust, reusable, readily assembled from inexpensive building blocks and constitutes a versatile and powerful vehicle for gas sensing in general, bacterial monitoring in particular.

Nanoengineering Approaches Toward Artificial Nose

Significant scientific efforts have been made to mimic and potentially supersede the mammalian nose using artificial noses based on arrays of individual cross-sensitive gas sensors over the past couple decades. To this end, thousands of research articles have been published regarding the design of gas sensor arrays to function as artificial noses. Nanoengineered materials possessing high surface area for enhanced reaction kinetics and uniquely tunable optical, electronic, and optoelectronic properties have been extensively used as gas sensing materials in single gas sensors and sensor arrays. Therefore, nanoengineered materials address some of the shortcomings in sensitivity and selectivity inherent in microscale and macroscale materials for chemical sensors. In this article, the fundamental gas sensing mechanisms are briefly reviewed for each material class and sensing modality (electrical, optical, optoelectronic), followed by a survey and review of the various strategies for engineering or functionalizing these nanomaterials to improve their gas sensing selectivity, sensitivity and other measures of gas sensing performance. Specifically, one major focus of this review is on nanoscale materials and nanoengineering approaches for semiconducting metal oxides, transition metal dichalcogenides, carbonaceous nanomaterials, conducting polymers, and others as used in single gas sensors or sensor arrays for electrical sensing modality. Additionally, this review discusses the various nano-enabled techniques and materials of optical gas detection modality, including photonic crystals, surface plasmonic sensing, and nanoscale waveguides. Strategies for improving or tuning the sensitivity and selectivity of materials toward different gases are given priority due to the importance of having cross-sensitivity and selectivity toward various analytes in designing an effective artificial nose. Furthermore, optoelectrical sensing, which has to date not served as a common sensing modality, is also reviewed to highlight potential research directions. We close with some perspective on the future development of artificial noses which utilize optical and electrical sensing modalities, with additional focus on the less researched optoelectronic sensing modality.

Application Effect Analysis of Three Methods of Heating and Humidification for Weaning Patients in ICU

Objectives To investigate the effects of artificial nose, Venturi device+thermostatic humidification T-tube, Venturi device+thermostatic humidification T-tube+PEEP valve in patients with tracheotomy in ICU.Design: Cohort study.Setting: Tertiary academic medical center.Patients: A total of 215 patients were engaged in this study. Clinical and laboratory examination data were used to determine the heating and humidification efficiency of 3 different methods.Methods: We conducted randomized controlled trial. Patients who successfully weaned from mechanical ventilation were enrolled, and every patient was randomized to receive one of the above three interventions. Three groups of patients were compared in terms of vital signs, the effect of artificial airway heating and humidification, and blood gas indicators. Basic patient data (age, gender, mechanical ventilation duration, ICU stay, disease type) were recorded. Vital signs include heart rate, blood pressure, respiratory rate, oxygen saturation; The effect of heating and humidifying the artificial airway were defined as the number of sputum suction and coughing within 24 hours, sputum characteristics, whether there is bloody sputum formation, whether there is phlegm callus formation; Blood gas indicators include pH, oxygen partial pressure, carbon dioxide partial pressure, lactic acid, residual base, and bicarbonate.Results: In terms of the heating and humidification effect of patients in ICU, the heating and humidification effect of the Venturi device+T-tube method and the Venturi device+the T-tube +PEEP valve method were significantly superior to those of artificial nasal method (sputum suction number: P =0.0001; sputum scab: P =0.03; Number of cough: P =0.007).SpO2 was significantly higher (P =0.004) in the Venturi device+T tube+PEEP valve than that in the Venturi device+T tube.Conclusion: Compared with the artificial nose method, the T-piece+venturi device and thermostatic heating and humidifying T-tube +PEEP valve method is better. In terms of improving oxygenation, the Venturi device and the thermostatic humidification T tube +PEEP valve could improve the patient's oxygen sum more than the Venturi device and the thermostatic humidification T tube.

Three-dimensional porous SERS powder for sensitive liquid and gas detections fabricated by engineering dense “hot spots” on silica aerogel

A 3D porous SERS powder was developed in this study. Highly sensitive and homogeneous SERS detections on liquid and gas have been achieved, demonstrating potential application for an artificial “nose”.

Investigation of body secretions as bioindicators in cattle estrus detection

The accurate determination of estrus has a fundamental role in cattle reproduction management. The determination of volatile chemical compounds (pheromones) secreted only during estrus in all body fluids can be used for determining accurate estrus time and artificial insemination time and have a potential role in technological animal reproduction control. In this study, Holstein cows were synchronized and their sudor, urine, feces, milk, saliva, vaginal secretions, and blood samples were taken in the preestrus, estrus, and postestrus periods and analyzed by gas chromatography-mass spectrometry for determination of volatile odor compounds. A total of 531 volatile compounds were detected in the preestrus period, 538 in the estrus period, and 494 in the postestrus period. Among these, 8 compounds were found to be common in all body fluids and the ratio of these compounds to those detected in all body fluids was 2.6%. Especially in the estrus, 3-methyl pentane, hexanal, 4-methylphenol (p-cresol), phenylacetaldehyde, 3-phenylpropiononitrile, 1 H-indole, cyclotetrasiloxane octamethyl and pentane 2-methyl were detected. Biotechnology devices such as artificial nose with sensors can be developed, recognizing estrus-specific volatile compounds detected from all body fluids only in estrus period.