Lung Ventilation and Gas Exchange in Asymptomatic Emphysema

2015 ◽  
pp. 117-132
Author(s):  
J. E. Cotes
Keyword(s):  
Gas Exchange ◽  
Lung Ventilation

scholarly journals Venovenosus extrakorporális membránoxigenizációval (ECMO) végzett mellkassebészeti műtétek tapasztalatai Magyarországon. Retrospektív klinikai tanulmány

2019 ◽  
Vol 160 (42) ◽  
pp. 1655-1662
Author(s):  
Ildikó Madurka ◽  
Jenő Elek ◽  
Ákos Kocsis ◽  
László Agócs ◽  
Ferenc Rényi-Vámos
Keyword(s):  
Gas Exchange ◽  
Lung Resection ◽  
Lung Ventilation ◽  
Clinicopathological Characteristics ◽  
Morbidity And Mortality ◽  
Related Complication ◽  
Single Lung Ventilation ◽  
Perioperative Morbidity ◽  
Venovenous Ecmo ◽  
Vv Ecmo

Abstract: Introduction: Most modern thoracic operations are performed with single-lung ventilation balancing between convenient surgical approach and adequate gas exchange. The technical limitations include difficult airways or insufficient parenchyma for the intraoperative single-lung ventilation. Earlier, cardiopulmonary bypass was the only solution, however, today the extracorporeal membrane oxygenation is in the forefront. Aim: We retrospectively analysed our elective operations by use of venovenous ECMO to assess the indication, safety, perioperative morbidity and mortality. Patients and method: 12 patients were operated using venovenous (VV-) ECMO between 28 April 2014 and 30 April 2018 in the National Institute of Oncology. The main clinicopathological characteristics, data regarding the operation, the use of ECMO and survival were collected. Results: The mean age was 45 years, 2 patients had benign and 10 had malignant diseases. Extreme tracheal stricture was the indication for ECMO in 3 cases, while 4 patients had previous lung resection and lacked enough parenchyma for single-lung ventilation. 5 patients had both airway and parenchymal insufficiency. The average time of apnoea was 142 minutes without interruption in any of the cases. We did not experience any ECMO-related complication. We had no intraoperative death and 30-day mortality was 8.33%. Conclusion: In case of technical inoperability, when there is no airway or insufficient parenchyma for gas exchange, but pulmonary vascular bed is enough and there is no need for great-vessel resection, VV-ECMO can safely replace the complete gas exchange without further risk of bleeding. The use of VV-ECMO did not increase the perioperative morbidity and mortality. Previously inoperable patients can be operated with VV-ECMO. Orv Hetil. 2019; 160(42): 1655–1662.

Ventilation and gas exchange in lizards during treadmill exercise.

1997 ◽  
Vol 200 (20) ◽  
pp. 2629-2639
Author(s):  
T Wang ◽  
D R Carrier ◽  
J W Hicks
Keyword(s):  
Exchange Rate ◽  
Gas Exchange ◽  
Oxygen Uptake ◽  
Minute Ventilation ◽  
Oxygen Demand ◽  
Lung Ventilation ◽  
Iguana Iguana ◽  
Maximal Aerobic Speed ◽  
Gas Exchange Rate ◽  
Treadmill Locomotion

The extent to which lizards ventilate their lungs during locomotion is controversial. Direct measurements of airflow across the nostrils suggest a progressive reduction in tidal volume and minute ventilation with increased running speed, while other studies have demonstrated that arterial PO2 remains constant during exercise. To resolve these conflicting findings, we measured minute ventilation and gas exchange rate in five specimens of Varanus exanthematicus and five specimens of Iguana iguana during treadmill locomotion at speeds between 0.14 and 1.11ms-1 at 35 degrees C. These speeds are much lower than maximal running speeds, but are greater than the maximal aerobic speed. In both species, the ventilatory pattern during locomotion was highly irregular, indicating an interference between locomotion and lung ventilation. In Varanus exanthematicus, treadmill locomotion elicited a six- to eightfold increase in minute ventilation from a pre-exercise level of 102mlkg-1min-1, whereas the rate of oxygen uptake increased approximately threefold (from 3.9 to 12.6mlkg-1min-1). After exercise, both minute ventilation and gas exchange rate decreased immediately. Because minute ventilation increased more than did oxygen consumption, an increase in lung PO2 during exercise is predicted and, thus, Varanus exanthematicus appears effectively to ventilate its lungs to match the increased metabolic rate during locomotion at moderate speed. In Iguana iguana, both minute ventilation and gas exchange rate increased above resting values during locomotion at 0.28ms-1, but both decreased with further increases in locomotor speed. Furthermore, following exercise, both minute ventilation and oxygen uptake rate increased significantly. Iguana iguana, therefore, appears to be unable to match the increased oxygen demand with adequate ventilation at moderate and higher speeds.

Gas exchange and its control in non-steady-state systems: the consequences of evolution from water to air breathing in the vertebrates

1988 ◽  
Vol 66 (1) ◽  
pp. 109-123 ◽  
Author(s):  
G. Shelton ◽  
P. C. Croghan
Keyword(s):  
Steady State ◽  
Gas Exchange ◽  
Dynamic Models ◽  
Continuous Process ◽  
Circulatory System ◽  
Lung Ventilation ◽  
Burst Duration ◽  
Air Breathing ◽  
Arterial Blood ◽  
Dissociation Curves

Control of breathing and gas exchange has been extensively investigated in unimodal animals, particularly mammals, in which ventilation is characteristically a regular and continuous process and gas exchange approximates to a steady-state system. Both static and dynamic models have been developed in control-theory analyses. Similar analyses are possible in unimodal fish, though few have been carried out. Control in bimodal animals, such as air-breathing fish and amphibians, is more difficult to understand and model. The evolutionary change from water to air breathing in vertebrates involves not only the adjustment of many control processes but also the development, in the early stages, of non steady states in gas exchangers, blood, and tissues. A simple control-system model, differing from mammalian counterparts in its greater emphasis on storage functions and its intermittently activated controller, is described for two suggested stages in the evolution of air breathing. The first of these stages is air gulping, in which a fixed and rather brief pattern of air breathing is activated by internal signals generated as a result of the inadequacy of the gills to provide sufficient oxygen for tissue metabolism. The second stage is that of burst breathing, in which lung ventilation is both begun and ended by internal signals so that burst duration is variable. The effects of adjusting parameters on variables of evolutionary importance, such as dive duration, burst duration, store renewal, and metabolic rate, can be examined in these two versions of the model. Refinements to incorporate arterial and venous compartments in the circulatory system, the shunting of venous and arterial blood streams in the heart, realistic oxygen dissociation curves, controller inputs from a wider range of sources, and the capacity to respond to some conditions with changes in ventilation rate as well as in burst and dive durations, are being developed. They should make the complex, non-steady-state interactions between gas exchangers, circulating blood, and tissues easier to understand and indicate the likely steps toward the evolution of steady-state systems seen in birds and mammals.

Lung Recruitment Improves the Efficiency of Ventilation and Gas Exchange During One-Lung Ventilation Anesthesia

2004 ◽  
pp. 1604-1609 ◽  
Author(s):  
Gerardo Tusman ◽  
Stephan H. B??hm ◽  
Fernando Su??rez Sipmann ◽  
Stefan Maisch
Keyword(s):  
Gas Exchange ◽  
Lung Ventilation ◽  
Lung Recruitment ◽  
One Lung Ventilation

scholarly journals Anaesthesiological Maintenance of Patients with Obesity

2008 ◽  
Vol 62 (4-5) ◽  
pp. 189-192
Author(s):  
Margarita Vyzhigina ◽  
Viktor Titov ◽  
Svetlana Zhukova ◽  
Oksana Kurilova
Keyword(s):  
Morbid Obesity ◽  
Body Weight ◽  
Gas Exchange ◽  
High Efficiency ◽  
Lung Ventilation ◽  
Ideal Body Weight ◽  
Intermittent Positive Pressure Ventilation ◽  
Positive Pressure ◽  
Ideal Body ◽  
Special Approach

Anaesthesiological Maintenance of Patients with Obesity Pathophysiological features of morbid obesity and the associated functional-anatomical changes in an organism demand the special approach to anaesthesiological maintenance. Methods of anaesthesiological protection and maintenance of effective gas exchange in morbide obesity patients have been proved. Anaesthesias for 110 patients have been analysed. Multicomponent anesthesia with traditional and combined artificial lung ventilation (ALV) (IPPV+HFJV) (intermittent positive pressure ventilation and high frequency jet ventilation) was used. Since 2000, morbid obesity patients receive intubation only with fibrobronchoscope with self breathing under local anesthesia. In IPPV for morbid obesity patients high peak pressure in airways, low V/Q, and low PaO2 occurs. Technology of combined ALV (IPPV+HFJV) has led to pressure decrease in airways and to effective arterial oxygenation improvement, intrapulmonary shunt has decreased. Retrospective analysis of anesthesia components revealed that the applied anaesthetic doses correspond to calculations on ideal body weight, and not true weight. Thus, anaesthesiological maintenance of operated patients with morbid obesity requires trachea intubation with fibroscope under local anaesthesia with self-breathing; high efficiency of ALV methods, allowing lower pressure in airways and high oxygenation (IPPV+HFJV), which provides effective gas exchange; doses correction of intravenous anaesthetics for due body weight is required.

scholarly journals Inflammation during Lung Cancer Progression and Ethyl Pyruvate Treatment Observed by Pulmonary Functional Hyperpolarized 129Xe MRI in Mice

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Atsuomi Kimura ◽  
Seiya Utsumi ◽  
Akihiro Shimokawa ◽  
Renya Nishimori ◽  
Neil J. Stewart ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Gas Exchange ◽  
Cancer Progression ◽  
Ethyl Pyruvate ◽  
Late Phase ◽  
Precancerous Lesion ◽  
Lung Ventilation ◽  
Negative Control ◽  
Functional Changes ◽  
Hyperpolarized 129Xe

This study aimed to assess the suitability of hyperpolarized 129Xe (HPXe) MRI for noninvasive longitudinal evaluation of pulmonary function in preclinical lung cancer models. A mouse model of lung cancer (LC) was induced in 5 mice by intraperitoneal injection of urethane, while a negative-control (NC) mice (N = 5) was prepared by injection of saline solution. Longitudinal HPXe MRI was performed over a 5-month period to monitor lung ventilation and gas exchange. The treatment efficacy of ethyl pyruvate (EP), an anti-inflammatory drug, to the mouse LC model was monitored using HPXe MRI by commencing administration of EP pre (early-phase) and 1-month post (late-phase) injection of urethane (N = 5 mice for each group). Gas-exchange function in LC mice was significantly reduced at 1-month after urethane injection compared with NC mice administered with saline ( P < 0.01 ). Thereafter, it remained consistently lower than that of the NC group for the full 5-month measurement period. In contrast, the ventilation function of the LC model mice was not significantly different to that of the NC mice. Histological analysis revealed alveolar epithelial hyperplasia in LC mice alveoli at 1 month after urethane injection, and adenoma was confirmed 3 months after the injection. The early- and late-phase EP interventions were found to improve HPXe MRI metrics (reduced at 1 month postinjection of urethane) and significantly inhibit tumor growth. These results suggest that HPXe MRI gas-exchange metrics can be used to quantitatively assess changes in the precancerous lesion microenvironment and to evaluate therapeutic efficacy in cancer. Thus, HPXe MRI can be utilized to noninvasively monitor pulmonary pathology during LC progression and can visualize functional changes during therapy.

scholarly journals Ventilation and gas exchange during treadmill locomotion in the American alligator (Alligator mississippiensis)

2000 ◽  
Vol 203 (11) ◽  
pp. 1671-1678 ◽  
Author(s):  
C.G. Farmer ◽  
D.R. Carrier
Keyword(s):  
Gas Exchange ◽  
Large Volume ◽  
Low Frequency ◽  
Lung Ventilation ◽  
Alligator Mississippiensis ◽  
Air Breathing ◽  
Air Convection ◽  
Exercise Ventilation ◽  
Anatomical Characters ◽  
Treadmill Locomotion

A number of anatomical characters of crocodilians appear to be inconsistent with their lifestyle as sit-and-wait predators. To address this paradoxical association of characters further, we measured lung ventilation and respiratory gas exchange during walking in American alligators (Alligator mississippiensis). During exercise, ventilation consisted of low-frequency, large-volume breaths. The alligators hyperventilated severely during walking with respect to their metabolic demands. Air convection requirements were among the highest and estimates of lung P(CO2) were among the lowest known in air-breathing vertebrates. Air convection requirements dropped immediately with cessation of exercise. These observations indicate that the ventilation of alligators is not limited by their locomotor movements. We suggest that the highly specialized ventilatory system of modern crocodilians represents a legacy from cursorial ancestors rather than an adaptation to a lifestyle as amphibious sit-and-wait predators.

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