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1.
Rev. colomb. anestesiol ; 49(1): e500, Jan.-Mar. 2021. graf
Article in English | LILACS, COLNAL | ID: biblio-1149798

ABSTRACT

Abstract Hemodynamic monitoring of a critically ill patient is an indispensable tool both inside and outside intensive care; we currently have invasive, minimally invasive and non-invasive devices; however, no device has been shown to have a positive impact on the patient's evolution; arterial and venous blood gases provide information on the patient's actual microcirculatory and metabolic status and may be a hemodynamic monitoring tool. We aimed to carry out a non-systematic review of the literature of hemodynamic monitoring carried out through the variables obtained in arterial and venous blood gases. A non-systematic review of the literature was performed in the PubMed, OvidSP and ScienceDirect databases with selection of articles from 2000 to 2019. It was found that there are variables obtained in arterial and venous blood gases such as central venous oxygen saturation (SvcO2), venous-to-arterial carbon dioxide pressure (Δpv-aCO2), venous-to-arterial carbon dioxide pressure/arteriovenous oxygen content difference (Δpv-aCO2/ΔCavO2) that are related to cellular oxygenation, cardiac output (CO), microcirculatory veno-arterial flow and anaerobic metabolism and allow to assess tissue perfusion status. In conclusion, the variables obtained by arterial and venous blood gases allow for non-invasive, accessible and affordable hemodynamic monitoring that can guide medical decision-making in critically ill patients.


Resumen El monitoreo hemodinámico de un paciente en estado crítico es una herramienta indispensable tanto dentro como fuera de la terapia intensiva; actualmente se cuenta con dispositivos invasivos, mínimamente invasivos y no invasivos; sin embargo, ningún dispositivo ha demostrado tener impacto positivo en la evolución del paciente; la gasometría arterial y venosa proporcionan información del estado microcirculatorio y metabólico real del paciente pudiendo ser una herramienta de monitoreo hemodinámico. El objetivo de esta revisión fue realizar una revisión no sistemática de la literatura del monitoreo hemodinámico realizado mediante las variables obtenidas en la gasometría arterial y venosa. Se estudiaron las bases de datos de PubMed, OvidSP y ScienceDirect con selección de artículos del 2000 al 2019. Se encontró que hay variables obtenidas en la gasometría arterial y venosa como la saturación venosa central de oxígeno (SvcO2), la diferencia de presión venoarterial de dióxido de carbono (Δpv-aCO2), la diferencia de presión venoarterial de dióxido de carbono/diferencia del contenido arteriovenoso de oxígeno (Δpv-aCO2/ΔCa-vO2) que están relacionadas con la oxigenación celular, con el gasto cardiaco (GC), con el flujo venoarterial microcirculatorio y con el metabolismo anaerobio que permiten realizar una valoración del estado de perfusión tisular. En conclusión, las variables obtenidas por gasometría arterial y venosa permiten realizar un monitoreo hemodinámico no invasivo, accesible y asequible que pueden guiar la toma de decisiones médicas en el paciente en estado crítico.


Subject(s)
Humans , Blood Gas Analysis , Hemodynamic Monitoring , Microcirculation , Carbon Dioxide , Decision Making
2.
Chinese Journal of Biotechnology ; (12): 1229-1236, 2021.
Article in Chinese | WPRIM | ID: wpr-878626

ABSTRACT

Lactate is an important industrial chemical and widely used in various industries. In recent years, with the increasing demand for polylactic acid (PLA), the demand for lactate raw materials is also increasing. The contradiction between the high cost and the market demand caused by the heterotrophic production of lactate attracts researchers to seek other favorable solutions. The production of lactate from photosynthetic carbon fixation by cyanobacteria is a potential new raw material supply strategy. Based on the photosynthetic autotrophic cell factory, it can directly produce high optical purity lactate from carbon dioxide on a single platform driven by solar energy. The raw materials are cheap and easy to obtain, the process is simple and controllable, the products are clear and easy to separate, and the double effects of energy saving and emission reduction and production of high value-added products are achieved at the same time, which has important research and application value. This paper reviews the development history of cyanobacteria carbon sequestration to produce lactate, summarizes its research progress and encounters technical difficulties from the aspects of metabolic basis, metabolic engineering strategy, metabolic kinetics analysis and technical application, and prospects the future of this technology.


Subject(s)
Carbon Cycle , Carbon Dioxide , Cyanobacteria/genetics , Lactic Acid , Metabolic Engineering , Photosynthesis
3.
Rev. Col. Bras. Cir ; 48: e20202632, 2021. graf
Article in English | LILACS | ID: biblio-1155371

ABSTRACT

ABSTRACT The current Covid-19 pandemic has been the most discussed topic of the year, mostly about protection and ways to avoid dissemination of the virus. In the healthcare system, especially in the operating rooms, the viability of laparoscopic surgery was questioned, mostly because of the transmission through aerosol. This article tries to suggest a way to minimize risks of laparoscopic surgery, during this situation, by using electrostatic filters, a simple, effective and low cost alternative.


RESUMO A atual pandemia do Covid-19 tem sido o assunto mais discutido do ano de 2020, principalmente no que se refere a proteção e as formas de limitar a disseminação do vírus. No cenário hospitalar, mais especificamente no centro cirúrgico, a viabilidade da cirurgia laparoscópica foi questionada, em relação a transmissibilidade do vírus por aerossol. Este artigo sugere uma forma de minimizar os riscos em cirurgias laparoscópicas durante esse cenário, com o uso de filtros eletrostáticos de ventilação mecânica. Uma alternativa simples, eficaz e de baixo custo.


Subject(s)
Humans , Pneumoperitoneum , Carbon Dioxide , Infection Control/methods , Laparoscopy , COVID-19/prevention & control , Pandemics
4.
Rev. argent. cir ; 112(4): 438-444, dic. 2020. graf, il
Article in Spanish | LILACS, BINACIS | ID: biblio-1288155

ABSTRACT

RESUMEN Antecedentes: la pandemia de COVID-19 presentó nuevos desafíos en el manejo de la patología quirúrgica laparoscópica. Objetivos: presentar el sistema de filtrado de bajo costo utilizado para la laparoscopia durante la pandemia en nuestro Servicio de Cirugía. Material y métodos: se realizó búsqueda bibliográfica y se diseñó un protocolo y sistema de filtrado para evacuar el CO2 contenido en el neumoperitoneo para evitar el contagio por el virus SARS-CoV-2. Resultados: se pone en práctica el empleo de un sistema de filtrado del neumoperitoneo en época de pandemia, el cual es de bajo costo y armado sencillo con materiales disponibles habitualmente en las áreas quirúrgicas. Conclusiones: la cirugía laparoscópica es factible durante la pandemia de SARS-CoV-2 utilizando un método sencillo y económico de filtrado del neumoperitoneo.


ABSTRACT Background: Background: the COVID-19 pandemic gave rise to new challenges in the management of laparoscopic surgery. Objectives: the aim of this study is to present a low-cost filtering system used for laparoscopic surgery during the pandemic in our Department of Surgery. Material and methods : a bibliographic search was conducted and a protocol and filtering system were designed to evacuate the pneumoperitoneum avoiding contact with the SARS-CoV-2. Results: this low-cost filtering system to evacuate the pneumoperitoneum during the pandemic is easy to assemble using materials that are usually available at the operating room. Conclusions: laparoscopic surgery is feasible during the COVID-19 pandemic using a simple, low-cost carbon dioxide filtering system.


Subject(s)
Carbon Dioxide , Laparoscopy , Filtration/methods , COVID-19/prevention & control , Pneumoperitoneum/prevention & control , Protocols , Personal Protective Equipment , SARS-CoV-2
5.
Int. j interdiscip. dent. (Print) ; 13(1): 40-43, abr. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1114892

ABSTRACT

OBJETIVO: El propósito de esta revisión fue evaluar sistemáticamente la literatura científica sobre los resultados clínicos que se obtienen al remover los frenillos aberrantes al utilizar los procedimientos quirúrgicos convencionales y el láser. MATERIALES Y MÉTODOS: Búsqueda detallada en las bases de datos PubMed, ScienceDirect, Cochrane y SciELO para obtener la información más actualizada los resultados clínicos (dolor posoperatorio, dolor al hablar, dolor al masticar y complicaciones posquirúrgicas) entre las técnicas convencionales (uso del escalpelo) y las técnicas de remoción con el láser (búsqueda de ensayos clínicos). RESULTADOS: De los 501 archivos identificados inicialmente, se excluyeron reportes clínicos, revisiones, estudios observacionales, comentarios, estudios con pacientes pediátricos, etc. Se incluyeron cuatro ensayos clínicos que contrastaron las variables entre la técnica convencional y las técnicas con el láser Nd: YAG y láser CO2 CONCLUSIÓN: La percepción del dolor posoperatorio, el dolor al hablar y el disconfort al masticar luego de la frenectomía es menor en las técnicas que utilizan el láser de Nd: YAG y CO2 frente a las técnicas que utilizan el escalpelo. El tiempo quirúrgico con el uso del láser es significativamente menor que al utilizar el escalpelo. La heterogeneidad de los estudios limita la realización de un metanálisis con respecto a los resultados.


OBJECTIVE: The purpose of this review was to evaluate systematically the scientific literature on the clinical results obtained by removing aberrant frenulums using conventional surgical procedures and laser. MATERIALS AND METHODS: A detailed search was performed in the PubMed, ScienceDirect, Cochrane and SciELO databases to obtain the most up-to-date clinical results (postoperative pain, pain when speaking, pain when chewing and postoperative complications) among conventional (scalpel use) and laser removal techniques (search for clinical trials). RESULTS: Of the 501 records initially identified, clinical reports, reviews, observational studies, comments, studies with pediatric patients, etc. were excluded. We included four clinical trials that contrasted the variables between the conventional technique and the techniques with the Nd: YAG laser and CO2 laser. CONCLUSION: The perception of postoperative pain, pain when speaking and chewing discomfort after frenectomy is lower in the techniques using the Nd: YAG and CO2 laser versus the techniques using the scalpel. The surgical time when using of laser is significantly lower than when using the scalpel. The heterogeneity of the studies limits the performance of a meta-analysis with respect to the results.


Subject(s)
Humans , Oral Surgical Procedures/methods , Labial Frenum/surgery , Postoperative Complications , Surgery, Oral , Carbon Dioxide , Treatment Outcome , Laser Therapy , Lasers, Solid-State , Operative Time
6.
Electron. j. biotechnol ; 44: 47-57, Mar. 2020. tab, ilus, graf
Article in English | LILACS | ID: biblio-1087699

ABSTRACT

BACKGROUND: The determination of kinetic parameters and the development of mathematical models are of great interest to predict the growth of microalgae, the consumption of substrate and the design of photobioreactors focused on CO2 capture. However, most of the models in the literature have been developed for CO2 concentrations below 10%. RESULTS: A nonaxenic microalgal consortium was isolated from landfill leachate in order to study its kinetic behavior using a dynamic model. The model considered the CO2 mass transfer from the gas phase to the liquid phase and the effect of light intensity, assimilated nitrogen concentration, ammonium concentration and nitrate concentration. The proposed mathematical model was adjusted with 13 kinetic parameters and validated with a good fit obtained between experimental and simulated data. CONCLUSIONS: Good results were obtained, demonstrating the robustness of the proposed model. The assumption in the model of DIC inhibition in the ammonium and nitrate uptakes was correct, so this aspect should be considered when evaluating the kinetics with microalgae with high inlet CO2 concentrations.


Subject(s)
Carbon Dioxide/analysis , Microalgae/radiation effects , Microalgae/physiology , Kinetics , Weirs , Photons , Microalgae/isolation & purification , Microalgae/growth & development , Photobioreactors , Waste Water , Models, Biological , Nitrates , Nitrogen
7.
Chinese Journal of Biotechnology ; (12): 2126-2138, 2020.
Article in Chinese | WPRIM | ID: wpr-878472

ABSTRACT

Development of "liquid sunshine" could be a key technology to deal with the issue of fossil fuel depletion. β-caryophyllene is a terpene compound with high energy density and has attracted attention for its potential application as a jet fuel. The high temperature and high light-tolerant photosynthetic cyanobacterium Synechococcus elongatus UTEX 2973 (hereafter Synechococcus 2973), whose doubling time is as short as 1.5 h, has great potential for synthesizing β-caryophyllene using sunlight and CO₂. In this study, a production of ~121.22 μg/L β-caryophyllene was achieved at 96 h via a combined strategy of pathway construction, key enzyme optimization and precursor supply enhancement. In addition, a final production of ~212.37 μg/L at 96 h was realized in a high-density cultivation. To our knowledge, this is the highest production reported for β-caryophyllene using cyanobacterial chassis and our study provide important basis for high-density fuel synthesis in cyanobacteria.


Subject(s)
Biofuels/microbiology , Carbon Dioxide/metabolism , Light , Photosynthesis , Synechococcus/radiation effects
8.
Article in Chinese | WPRIM | ID: wpr-878390

ABSTRACT

OBJECTIVE@#To observe and compare the clinical efficacy of CO₂ fractional laser in the early control of scar post-secondary repair in patients with a cleft lip.@*METHODS@#In the treatment group, 43 patients with secondary repair of cleft lip were treated via CO₂ fractional laser. The control group covered 70 patients post-cheiloplasty. The effect in the two groups after six months was compared. The duration from the beginning of the laser treatment to surgery and patient gender were analyzed to determine if they affected the efficacy of the laser treatment for scars.@*RESULTS@#1) The curative effect in the treatment group was better than that in the control group (P<0.000 1), the total effectiveness rate was 90.7% in the treatment group. 2) No significant statistical difference in efficacy was observed between men and women (P=0.487). Moreover, no significant statistical difference in efficacy (P=0.055) was observed among patients one year after surgery, within the duration of <3 months, and within the duration of ≥3 months.@*CONCLUSIONS@#CO₂ fractional laser had a definite effect on the treatment of scar post-secondary repair in patients with a cleft lip. No significant correlation was observed between treatment effect and patient gender, and no difference was noted among patients one year after surgery. In the beginning of the laser treatment, no difference was observed between the durations of <3 months and ≥3 months after the reconstruction, Therefore, early intervention of scars a year after secondary repair of a cleft lip can achieve good results.


Subject(s)
Carbon Dioxide , Cicatrix/pathology , Cleft Lip/surgery , Female , Humans , Lasers , Male , Treatment Outcome
11.
Rev. colomb. gastroenterol ; 35(1): 18-24, 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1115597

ABSTRACT

Resumen Objetivo: comparar la magnitud del dolor y el perímetro abdominal; la incidencia del dolor y la distensión abdominal, y las complicaciones según el agente insuflante utilizado. Pacientes y método: estudio prospectivo analítico de cohorte. Se recolectaron datos de 43 colangiopancreatografías retrógradas endoscópicas (CPRE) y 20 colonoscopias insufladas con dióxido de carbono (CO2); para cada una se buscó un examen control con aire ambiente. En total, se sumaron 86 CPRE y 40 colonoscopias. Además, se realizó una caracterización clínica, un análisis bivariado y multivariado. Resultados: el procedimiento más doloroso fue la colonoscopia; sin embargo, el 60 % de los pacientes de colonoscopia, y el 70 % de aquellos de CPRE, no presentaron dolor 15 minutos después de haber despertado luego del examen. Asimismo, no se hallaron diferencias estadísticamente significativas según la indicación del examen, la presencia o intensidad de dolor al momento del procedimiento, la edad, el sexo o el diagnóstico. El riesgo relativo (RR) de dolor inmediato fue 4,8 veces superior, cuando la insuflación se realizó con aire en vez de CO2 (RR = 4,8; intervalo de confianza [IC], 95 %: 2,3 a 9,2; p <0,001). Entre tanto, el riesgo de distensión abdominal en el grupo con aire fue 2,6 veces superior, en comparación con el grupo insuflado con CO2 (RR = 2,6; IC, 95 %: 1,8 a 3,9; p <0,001). El CO2 redujo la probabilidad y la magnitud de la distensión abdominal y de los dolores inmediatos, posteriores a la colonoscopia o a la CPRE. No hubo complicaciones en ninguno de los 126 pacientes. Conclusiones: el dolor y la distensión abdominal se presentan con menor frecuencia e intensidad cuando se usa CO2 como agente insuflante. Ninguno de los procedimientos presentó complicaciones mayores.


Abstract Objective: This study compares the incidence of abdominal pain and distension, the magnitude of pain, abdominal perimeter, and related complications related to two different insufflating agents. Patients and Method: Prospective analytical cohort study. Data were collected from 43 performances of endoscopic retrograde cholangiopancreatography (ERCPs) and 20 colonoscopies in which patients were insufflated with CO2. A control examination using ambient air for insufflation was performed for each patient. In total, 86 ERCPs and 40 colonoscopies were performed. The study includes clinical characterizations, bivariate analysis and multivariate analysis. Results: The most painful procedure was colonoscopy, but 60% of colonoscopy patients and 70% of ERCP patients had no pain 15 minutes after waking up following their examinations. No statistically significant differences related to reasons for examination, presence or intensity of pain at the time of the procedure, age, sex or diagnosis were found. The relative risk (RR) of immediate pain is 4.8 times higher when insufflation is done with air instead of CO2 (RR = 4.8; 95% CI: 2.3 to 9.2; p <0.001). The risk of abdominal distension in the air group was 2.6 times higher than that of the group insufflated with CO2 (RR = 2.6; 95% CI: 1.8 to 3.9; p <0.001). CO2 reduces the likelihood and extent of abdominal distension and immediate post colonoscopy or ERCP pain. There were no complications in any of the 126 patients. Conclusions: Abdominal pain and bloating occur less frequently and less intensely when CO2 is used as an insufflating agent. None of the procedures presented major complications.


Subject(s)
Humans , Male , Female , Pain Measurement , Carbon Dioxide , Endoscopy , Control , Colonoscopy , Cholangiopancreatography, Endoscopic Retrograde , Air
12.
Braz. arch. biol. technol ; 63: e20190302, 2020. tab
Article in English | LILACS | ID: biblio-1132249

ABSTRACT

Abstract In a climate change context, the buildup of CO2 will affect plant communities worldwide. This study evaluated the effects of CO2 enrichment on the development and defense of two Cerrado native species Baccharis dracunculifolia and B. platypoda and their associated endophytic fungi richness. The study took place in Open-Top Chambers, two with ambient CO2 concentration (~400 ppm) and two in an enriched environment (~800 ppm). Baccharis platypoda developed 20% more leaves under enriched CO2 conditions, whereas B. dracunculifolia was 30% taller and showed 27% more leaves than those under ambient conditions. In both species, leaf polyphenol concentration did not differ between treatments. Nevertheless, polyphenol content had a positive correlation with plant height on both species' individuals grown under CO2 enriched conditions. Endophytic fungi richness and colonization rate on both plant species did not differ between ambient and enriched conditions. Our results show the positive effect of CO2 fertilizer in at least one of the measured growth parameters. An important new finding was a synergistic increase in growth and chemical defense in both studied species under enriched CO2 conditions, suggesting higher carbon assimilation and accumulation. This study suggests that the effects on primary productivity and secondary metabolites of Baccharis species will potentially reflect on the diversity and distribution of Cerrado plants and their associated animal communities.


Subject(s)
Carbon Dioxide/pharmacology , Baccharis/growth & development , Fertilizers , Endophytes/growth & development , Polyphenols/biosynthesis , Baccharis/microbiology , Baccharis/chemistry
13.
Int. arch. otorhinolaryngol. (Impr.) ; 23(3): 354-359, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1040017

ABSTRACT

Abstract Introduction Schwannomas are benign, solitary, encapsulated tumors that may originate at any site of the peripheral nervous system, with the exception of the olfactory and optic nerves. Schwannomas of the base of tongue are very rare, and only sporadic cases are documented. The tongue base represents a challenge for surgeons. Carbon dioxide (CO2) laser might provide an effective surgical option for such lesions because of the easy access to the lesion, the bloodless surgical field and optimum epithelization of wounds. Objective We present an unusual case of pedunculated schwannoma of the tongue base treated via transoral CO2-assisted excision. We also provide a review of the available literature, in English language, on humans. Data synthesis The authors searched the PubMed database and Google up to July 2018. The following search terms were applied: tongue and lingual, combined with schwannoma and neurilemmoma. Titles and abstracts were screened, and, then, only supraglottic (hypopharyngeal) tongue base masses were considered. Fourteen articles were included in this review, reporting 17 cases. The age of the patients ranged from 9 to 39 years, affecting predominantly females. Dysphagia and lump sensations were the most common presenting symptoms, and the mean follow-up period range was 1.5 to 60 months (mean = 13 months). There was no evidence of recurrence in any of the cases. Conclusion We could conclude that tongue base schwannomas are rare. Transoral complete excision of the tumor is the treatment of choice. CO2 laser surgery is a minimally invasive treatment option that has been performed in few reports with no recurrence and with favorable outcomes.


Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Aged , Tongue Neoplasms/surgery , Carbon Dioxide/therapeutic use , Laser Therapy/methods , Neurilemmoma/surgery , Tomography, X-Ray Computed , Diagnosis, Differential , Neurilemmoma/diagnosis , Neurilemmoma/pathology
14.
Rev. bras. ter. intensiva ; 31(2): 113-121, abr.-jun. 2019. graf
Article in Portuguese | LILACS | ID: biblio-1013758

ABSTRACT

RESUMO Objetivo: Descrever a transferência de energia do ventilador mecânico para os pulmões; o acoplamento entre a transferência de oxigênio por oxigenação por membrana extracorpórea venovenosa (ECMO-VV) e o consumo de oxigênio do paciente; a remoção de dióxido de carbono com ECMO; e o efeito potencial da oxigenação venosa sistêmica na pressão arterial pulmonar. Métodos: Modelo matemático com cenários hipotéticos e utilização de simulações matemáticas por computador. Resultados: A transição de ventilação protetora para ventilação ultraprotetora em um paciente com síndrome da angústia respiratória aguda grave e complacência respiratória estática de 20mL/cmH2O reduziu a transferência de energia do ventilador para os pulmões de 35,3 para 2,6 joules por minuto. Em um paciente hipotético, hiperdinâmico e ligeiramente anêmico com consumo de oxigênio de 200mL/minuto, é possível atingir saturação arterial de oxigênio de 80%, ao mesmo tempo em que se mantém o equilíbrio entre a transferência de oxigênio pela ECMO e o consumo de oxigênio do paciente. O dióxido de carbono é facilmente removido e a pressão parcial de dióxido de carbono normal é facilmente obtida. A oxigenação do sangue venoso, por meio do circuito da ECMO, pode direcionar o estímulo da pressão parcial de oxigênio na vasoconstrição pulmonar por hipóxia para valores normais. Conclusão: A ventilação ultraprotetora reduz amplamente a transferência de energia do ventilador para os pulmões. A hipoxemia grave no suporte com ECMO-VV pode ocorrer, a despeito do acoplamento entre a transferência de oxigênio, por meio da ECMO, e o consumo de oxigênio do paciente. A faixa normal de pressão parcial de dióxido de carbono é fácil de atingir. O suporte com ECMO-VV potencialmente alivia a vasoconstrição pulmonar hipóxica.


ABSTRACT Objective: To describe (1) the energy transfer from the ventilator to the lungs, (2) the match between venous-venous extracorporeal membrane oxygenation (ECMO) oxygen transfer and patient oxygen consumption (VO2), (3) carbon dioxide removal with ECMO, and (4) the potential effect of systemic venous oxygenation on pulmonary artery pressure. Methods: Mathematical modeling approach with hypothetical scenarios using computer simulation. Results: The transition from protective ventilation to ultraprotective ventilation in a patient with severe acute respiratory distress syndrome and a static respiratory compliance of 20mL/cm H2O reduced the energy transfer from the ventilator to the lungs from 35.3 to 2.6 joules/minute. A hypothetical patient, hyperdynamic and slightly anemic with VO2 = 200mL/minute, can reach an arterial oxygen saturation of 80%, while maintaining the match between the oxygen transfer by ECMO and the VO2 of the patient. Carbon dioxide is easily removed, and normal PaCO2 is easily reached. Venous blood oxygenation through the ECMO circuit may drive the PO2 stimulus of pulmonary hypoxic vasoconstriction to normal values. Conclusion: Ultraprotective ventilation largely reduces the energy transfer from the ventilator to the lungs. Severe hypoxemia on venous-venous-ECMO support may occur despite the matching between the oxygen transfer by ECMO and the VO2 of the patient. The normal range of PaCO2 is easy to reach. Venous-venous-ECMO support potentially relieves hypoxic pulmonary vasoconstriction.


Subject(s)
Humans , Female , Adult , Oxygen/metabolism , Respiratory Distress Syndrome/therapy , Extracorporeal Membrane Oxygenation/methods , Models, Theoretical , Oxygen Consumption , Computer Simulation , Carbon Dioxide/metabolism , Pulmonary Gas Exchange , Energy Transfer , Hypertension, Pulmonary/physiopathology , Lung/metabolism , Lung/pathology
15.
Rev. méd. Chile ; 147(6): 683-692, jun. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1020716

ABSTRACT

Background: Reproductive number (R0)-maps estimate risk zones of vector-borne diseases and geographical distribution changes under climate change. Aim: To map R0 aiming to estimate the epidemiological risk of Chagas disease in Chile, its distribution and possible changes due to the global climate change. Material and Methods: We used a relationship between R0 and entomological parameters of vectors as function of environmental variables, to map the risk of Chagas disease in Chile, under current and projected future environmental conditions. Results: We obtained a geographical R0 estimation of Chagas disease in Chile. The highest R0averages correspond to the Central-Northern regions of Chile. T. cruzi transmission area could increase in the future due to climate changes. Independent of the future condition, both for optimistic and pessimistic climate change scenarios, the area of potential risk for Chagas disease transmission would increase. The estimated R0 values suggest that, if a control of T. infestans is not maintained, Chagas disease endemic status will persist or increase, independently of the climate change scenarios. Conclusions: Mapping R0 values is an effective method to assess the risk of Chagas disease. The eventual increase in the transmission area of the disease is worrisome.


Subject(s)
Humans , Animals , Male , Female , Climate Change/statistics & numerical data , Chagas Disease/epidemiology , Risk Assessment/methods , Disease Vectors , Temperature , Triatoma , Trypanosoma cruzi , Carbon Dioxide , Chile/epidemiology , Risk Factors , Chagas Disease/transmission , Statistics, Nonparametric , Geography
16.
Article in English | WPRIM | ID: wpr-759546

ABSTRACT

BACKGROUND: Congenital central hypoventilation syndrome (CCHS) is a rare disorder characterized by alveolar hypoventilation and autonomic dysregulation. Patients with CCHS have adequate ventilation while awake but exhibit hypoventilation while asleep. More severely affected patients exhibit hypoventilation both when awake and when asleep. CASE: Here, we report a case of successful spinal anesthesia and postoperative epidural analgesia in a patient with CCHS who underwent orthostatic surgery. CONCLUSIONS: In patients with CCHS, anesthesia is used with the goal of minimizing respiratory depression to avoid prolonged mechanical ventilation. Regional anesthesia should be considered where appropriate. Continuous oxygen saturation and end-tidal carbon dioxide monitoring must be available.


Subject(s)
Analgesia, Epidural , Anesthesia , Anesthesia, Conduction , Anesthesia, Spinal , Hypoxia , Carbon Dioxide , Humans , Hypoventilation , Oxygen , Respiration, Artificial , Respiratory Insufficiency , Ventilation
17.
Article in English | WPRIM | ID: wpr-759531

ABSTRACT

BACKGROUND: Hypercapnia causes dilation of cerebral vessels and increases cerebral blood flow, resulting in increased intracranial pressure. Sevoflurane is reported to preserve cerebrovascular carbon dioxide reactivity. However, the contribution of inhaled anesthetics to vasodilatory responses to hypercapnia has not been clarified. Moreover, the cerebrovascular response to desflurane under hypercapnia has not been reported. We examined the effects of sevoflurane and desflurane on vasodilatory responses to hypercapnia in rats. METHODS: A closed cranial window preparation was used to measure the changes in pial vessel diameters. To evaluate the cerebrovascular response to hypercapnia and/or inhaled anesthetics, the pial vessel diameters were measured in the following states: without inhaled anesthetics at normocapnia (control values) and hypercapnia, with inhaled end-tidal minimal alveolar concentration (MAC) of 0.5 or 1.0 of either sevoflurane or desflurane at normocapnia, and an MAC of 1.0 of sevoflurane or desflurane at hypercapnia. RESULTS: Under normocapnia, 1.0 MAC, but not 0.5 MAC, of sevoflurane or desflurane dilated the pial arterioles and venules. In addition, under both 1.0 MAC of sevoflurane and 1.0 MAC of desflurane, hypercapnia significantly dilated the pial arterioles and venules in comparison to their diameters without inhaled anesthetics. The degrees of vasodilation were similar for desflurane and sevoflurane under both normocapnia and hypercapnia. CONCLUSIONS: Desflurane induces cerebrovascular responses similar to those of sevoflurane. Desflurane can be used as safely as sevoflurane in neurosurgical anesthesia.


Subject(s)
Anesthesia , Anesthetics , Animals , Arterioles , Carbon Dioxide , Cerebrovascular Circulation , Hypercapnia , Intracranial Pressure , Rats , Vasodilation , Venules
18.
Article in English | WPRIM | ID: wpr-759008

ABSTRACT

BACKGROUND: We investigated the relationship between serum total carbon dioxide (CO₂) and bicarbonate ion (HCO₃⁻) concentrations in pre-dialysis chronic kidney disease (CKD) patients and devised a formula for predicting low bicarbonate (HCO₃⁻< 24 mmol/L) and high bicarbonate (HCO₃⁻ ≥ 24 mmol/L) using clinical parameters. METHODS: In total, 305 samples of venous blood collected from 207 pre-dialysis patients assessed by CKD stage (G1 + G2, 46; G3, 50; G4, 51; G5, 60) were investigated. The relationship between serum total CO₂ and HCO₃⁻ concentrations was analyzed using Pearson’s correlation coefficient. An approximation formula was developed using clinical parameters correlated independently with HCO₃⁻ concentration. Diagnostic accuracy of serum total CO₂ and the approximation formula was evaluated by receiver operating characteristic curve analysis and a 2 × 2 table. RESULTS: Serum total CO₂ correlated strongly with HCO₃⁻ concentration (r = 0.91; P < 0.001). The following approximation formula was obtained by a multiple linear regression analysis: HCO₃⁻ (mmol/L) = total CO₂ − 0.5 × albumin − 0.1 × chloride − 0.01 × (estimated glomerular filtration rate + blood glucose) + 15. The areas under the curves of serum total CO₂ and the approximation formula for detection of low bicarbonate and high bicarbonate were 0.981, 0.996, 0.993, and 1.000, respectively. This formula had superior diagnostic accuracy compared with that of serum total CO₂ (86.6% vs. 81.3%). CONCLUSION: Serum total CO₂ correlated strongly with HCO₃⁻ concentration in pre-dialysis CKD patients. An approximation formula including serum total CO₂ showed superior diagnostic accuracy for low and high bicarbonate compared with serum total CO₂.


Subject(s)
Acid-Base Equilibrium , Bicarbonates , Carbon Dioxide , Carbon , Glomerular Filtration Rate , Humans , Linear Models , Renal Insufficiency, Chronic , ROC Curve
19.
Article in Korean | WPRIM | ID: wpr-758455

ABSTRACT

OBJECTIVE: Stroke volume (SV) measurements have been used to guide fluid management. Noninvasive, indirect, and convenient measurements of the SV for fluid therapy are required for most patients during spontaneous breathing (SB). On the other hand, the preferred method for an indirect prediction of the SV is unclear. This study examined the best of the indirect and predictable parameters responding to a SV variation during SB. METHODS: Hemodynamic parameters, such as collapsibility of the inferior vena cava (cIVC), peak velocity variation in the common carotid artery (pvvCCA), collapsibility of the internal jugular vein (cIJV), and end-tidal carbon dioxide (ETCO₂) were measured 180 times (6 different positions each in 30 normal subjects). The variables changed with the SV at the upper body elevation of 60°and 30°, in the supine position, at the lower body elevation of 60°and 30°, and lumbar elevation. RESULTS: The SV showed the highest value at 30°of lower body elevation. Following fixed position changes, the ETCO₂ during SB was the factor most correlated with the SV when compared to cIVC, cIJV, and pvvCCA (β coefficient, 2.432 vs. −0.41, −0.033, and −0.654; P=0.004). The adjusted ETCO₂ showed a significant change with the SV, even though the change in ETCO₂ was not large. CONCLUSION: ETCO₂ was less influenced by the SB than cIVC, pvvCCA, and cIJV because the ETCO₂ change was in accordance but the variations of the other blood vessels did not coincide with a SV change. Therefore, ETCO₂ monitoring for predicting the SV would be more important than the variations in the vessels during SB.


Subject(s)
Blood Vessels , Carbon Dioxide , Carbon , Cardiac Output , Carotid Artery, Common , Fluid Therapy , Hand , Hemodynamics , Humans , Jugular Veins , Methods , Respiration , Stroke Volume , Stroke , Supine Position , Ultrasonography , Vena Cava, Inferior
20.
Article in English | WPRIM | ID: wpr-762782

ABSTRACT

BACKGROUND: Lidocaine spray is a local anesthetic that improves random-pattern skin flap survival. The fractional ablative carbon dioxide laser (FxCL) produces vertical microchannels that delivers topically applied drugs to the skin. In this study, we hypothesized that FxCL therapy would enhance the lidocaine effect to improve random-pattern skin flap survival in rats. METHODS: McFarlane random-pattern skin flaps were elevated in 48 rats, which were divided into four groups according to treatment: FxCL+lidocaine, FxCL, lidocaine, and nontreatment (control). On postoperative day 7, necrotic flap areas, the number of capillary vessels, and neutrophil count were evaluated. Anti-rat vascular endothelial growth factor (VEGF) and CD31 antibody activity were also evaluated by immunohistochemical staining. RESULTS: Flap survival rate was 53.41%±5.43%, 58.16%±4.80%, 57.08%±5.91%, and 69.08%±3.20% in the control, lidocaine, FxCL, and FxCL+lidocaine groups, respectively. Mean neutrophil count in the intermediate zone excluding the necrotic tissue was 41.70±8.40, 35.43±6.41, 37.23±7.15, and 27.20±4.24 cells/field in the control, lidocaine, FxCL, and FxCL+lidocaine groups, respectively. Anti-rat VEGF and CD31 antibody activity were the highest in the FxCL+lidocaine group. CONCLUSION: FxCL with lidocaine had a positive effect on random-pattern skin flap survival in rats. Thus, FxCL with lidocaine spray should be considered as a new treatment option to improve flap viability.


Subject(s)
Animals , Capillaries , Carbon Dioxide , Carbon , Lasers, Gas , Lidocaine , Neutrophils , Rats , Skin , Survival Rate , Vascular Endothelial Growth Factor A
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