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At least 541 records · Page 30Linked to original sources
PubMed2005

A simple device for humidification of inspired gases during volatile anesthesia in rats.

The typical setup for administering volatile anesthetics to laboratory rats does not provide for humidification of the inspired gases, although it is known that failing to provide humidification can lead to airway inflammation and impaired pulmonary function during prolonged experimental protocols. We developed a simple humidification system in which a nebulizer was inserted into the nonrebreathing circuit used with a standard isoflurane vaporizer. We show here that the nebulizer system resulted in anesthetic stability, as measured by withdrawal reflex latency. Although the isoflurane concentration in the delivered gases was reduced, the reduction was a consistent percentage of the vaporizer output throughout the anesthetic range, thereby permitting straightforward adjustment of the vaporizer output.

Administration, Inhalation↗
PubMedDate not supplied

[Determination of butane in respiratory gases by means of GC/MS and GC/MS-MS].

Butane is inhaled in order to achieve a pleasurable state of intoxication. An overdose can lead to death. In two deaths from our own investigation material the circumstances were suspicious for the inhalation of liquid gas, and the presence of butane should be demonstrated in the respiratory gases. For detection, a method of ion trap gas chromatography/mass spectrometry (GC/MS) and tandem-mass spectrometry (GC/MS-MS) was developed, whereby the gas samples from the lung tissue were directly injected into the GC. The GC/MS tests revealed the presence of butane. Moreover, it was found that during the MS-MS tests reaction products appeared which had formed in the ion trap. Systematic investigations of these reaction products showed that these appeared regularly and could be used as additional backup for the proof of butane. Thus phenomena in the ion trap were used which would not have been expected to occur in normal mass spectrometry or tandem-MS and had not been described in the forensic literature so far. The detected amount of butane could be quantified by means of serial dilutions with nitrogen and room air. The described method shows that small molecules or gases can be demonstrated with the ion trap mass spectrometer.

Adolescent↗
PubMed1992

The effects of intraocular gases on rabbit blood-retinal barrier permeability.

The effects of intravitreal expansile gases, sulfur hexafluoride and octafluoropropane, as well as air and needle insertion alone were assessed by iris fluorescein angiography and blood-retinal barrier permeability determination. Iris angiography, at 3 days after injection, indicated no differences between experimental and paired control eyes. Vitreous fluorophotometry on day 1, day 4 and day 7 after gas or sham injection also showed no differences between paired control and experimental eyes regardless of which experimental condition was employed. The results indicate that these gases are non-toxic to the blood-retinal barrier over a 7 day time course.

Animals↗
PubMed2005

[Correlation between the area of arterial blood gases graph and the acid-base disturbance in 92 cases with chronic obstructive pulmonary disease].

OBJECTIVE: To study the correlation between the area of arterial blood gases graph (ABGG) and the acid-base disturbance (ABD). METHODS: Using the software developed by ourselves, the results of arterial blood gases and concomitant electrolyte (K(+), Na(+), Cl(-), HCO(3)(-)) determination in 313 episodes were analyzed in 92 cases with chronic obstructive pulmonary diseases (COPD) during hospitalization, and the correlation was studied. RESULTS: (1)On admission, among 92 cases, in 9 cases the results of blood gas analysis were in the area of compensated ventilation and deranged gas exchange (area IV), in 82 cases the results were in the area of insufficient ventilation and deranged gas exchange (area V), and 1 case in the area of excessive ventilation and deranged gas exchange (area VI). There were 8 types of the ABDs, and respiratory acidosis (RAC)+metabolic alkalosis (MAL), RAC, RAC+metabolic acidosis (MAC) with increase in anion gap (AG) ranked in above order. (2)At the time of discharge, in 2 cases the distribution of ABGG was in the normal area (area I), 5 cases in the area IV, 20 cases in the area V, and 1 case in the area VI. There were 5 types of the ABDs. RAC+MAL and RAC ranked in the first two positions. (3)During hospitalization, the correlations between the area of ABGG and ABD in 313 episodes were as follows: ABD normal and MAC of AG increased in the area I; ABD normal and MAL, MAC with AG increased, RAC+MAC, respiratory alkalosis (RAL)+MAL, MAL+MAC of AG increased, RAC+MAL+MAC of AG increased and RAL+MAL+MAC of AG increased in the area IV; RAC, MAL, RAC+MAL, RAC+MAC of AG increased, MAL+MAC of AG increased, and RAC+MAL+MAC of AG increased in the area V; MAC of AG increased, RAC+MAC, RAL+MAL, MAL+MAC of AG increased, and RAL+MAL+MAC of AG increased in the area VI. No ABD occurred in the areas II and III. CONCLUSION: The correlation between ABGG and ABD can be analyzed easily and quickly and the accuracy of results is ensured by using the software.

Acid-Base Equilibrium↗
PubMed2005

[Experimental study on changes in myocardial systolic function and arterial blood gases after impact injury to liver in rabbits].

OBJECTIVE: To explore the effects of impact injury of liver on myocardial systolic function and arterial blood gases in rabbits. METHODS: A model of hepatic impact injury was reproduced in rabbits by hitting the xiphoid area with two falling steel balls. Myocardial systolic function and arterial blood gases were measured respectively before injury, immediately and 0.5, 1, 2 hours after injury, and before the death. RESULTS: After injury, heart rate (HR), left ventricular systolic pressure (LVSP), the maximum change rate of left ventricular pressure rise and fall (+/-dp/dt max) descended significantly, while left ventricular end-diastolic pressure (LVEDP) showed no statistically significant change. At the same time, blood pH and HCO(3)(-) fell gradually, and negative base excess (BEecf) showed a significant increase, indicating metabolic acidosis gradually developed. There was no obvious significant difference in partial pressure of carbon dioxide in artery (PaCO(2)) between the values before and after injury. Partial pressure of oxygen in artery (PaO(2)) decreased gradually, but no significant differences were found between the values of 0.5 hour and 1 hour after injury and that before injury. CONCLUSION: After hepatic impact injury, myocardial systolic function deteriorates, metabolic acidosis appears.

Animals↗
PubMedDate not supplied

[Total intravenous anaesthesia without medical gases during economic blockade of the country].

In June and July 1992, when the corridor--through which we received the necessary medical supply--was closed, 61 patients (mostly wounded persons, 62%) underwent an urgent surgery. Because of the lack of oxygen and nitric oxydul, the patients were administered the intravenous total anaesthesia without medical gases. The control group was composed of 30 patients operated on in June and July 1991. The patients received Mydasolam (0.3 mg/kg) for general anaesthesia. Anaesthesia was maintained with Phentanil (15 mg/kg) and Alcurone (0.3 mg/kg). The control group was subjected to standard balanced anaesthesia (Thiopenton + nitric oxydul/oxygen + Halotin + Pancuron). The results of the two groups were compared. The observed, analysed and compared parameters were: the introduction period to anaesthesia, systolic blood pressure, diastolic blood pressure and time elapsed from the end of surgery to extubation. The introduction to anaesthesia was markedly unfavourable (p), the systolic and diastolic blood pressures, measured in five-minute intervals during anaesthesia, were significantly lower (p). The difference was especially great in the period from the end of surgery to the time of extubation: 73 +/- 12 minutes in the studied group, and 7 +/- 5 minutes in the control group. The method of total intravenous anaesthesia without medical gases satisfied our needs and expectations during the shortage of medical supplies. However, the standard balanced anaesthesia is a better method because it provokes a faster introduction to general anaesthesia, haemodynamic effects are less compromized, revival from anaesthesia is faster, the use of anaesthetics and equipment and engagement of the personnel are not great.

Adult↗
PubMed2006

[Effects of different durations of thromboembolism on blood gases, hemodynamics, pulmonary arteriography and thrombo-pathology in a canine model with selective embolization of pulmonary lobar arteries].

OBJECTIVE: To investigate the effects of different durations of thromboembolism on blood gases, hemodynamic parameters, pulmonary arteriography and thrombo-pathology in an animal model mimicking chronic pulmonary thromboembolism (PTE). METHODS: Sixteen dogs were embolized with five thrombi developed by autologous blood into the left lower pulmonary artery (n = 15) and the right lower pulmonary artery (n = 1, used to confirm the available method of selective embolization). The 15 dogs were divided into three groups: sham group (n = 5), one-week group (n = 5) and two-week group (n = 5) according to the different durations of embolization. Swan-Ganz catheter was used to guide a plastic duct, through which the thrombi were injected selectively into the left or right lower pulmonary artery by X-ray fluoroscopy. Local pulmonary arteriography of lower pulmonary arteries was taken. Blood pressure (BP), and blood gases were measured. Central venous pressure (CVP), mean pulmonary arterial pressure (MPAP), pulmonary arteriole wedge pressure (PAWP), and cardiac output (CO) were recorded, and pulmonary vascular resistance (PVR) was calculated. Each dog underwent muscular injection with tranexamic acid for one or two weeks to prevent thrombolysis. The lower lung lobe was dissected to confirm the thromboembolism after one or two weeks. The lung sections were stained with phosphotungstic acid hematoxylin (PTAH) to observe thromboemboli with optical microscopy. RESULTS: In the PTE group, PaO(2)/FiO(2), MPAP and PVR changed significantly as compared to baseline values (P < 0.05) after one hour of embolization, with MPAP increasing from (15 +/- 3) mm Hg to (21 +/- 4) mm Hg, PVR increasing from (178 +/- 114) mm Hg.s/L to (404 +/- 260) mm Hg.s/L, and PaO(2)/FiO(2) decreasing from (508 +/- 58) mm Hg to (395 +/- 100) mm Hg; these parameters returned to the baseline values one or two weeks later. After embolization, pulmonary arteriography demonstrated lower lobar artery cut-off perfusion defects. One week later, pulmonary arteriography demonstrated irregularities and stiffness of the arterial wall, enlarged proximal part of lower pulmonary artery and cut-off perfusion defects. Poor filling at embolus site was evident after embolization for two weeks. In the 1-week PTE group, organized tissue covered with the blue-purple fibrin nest was observed in the thrombus with PTAH stain. In the two-week group, the well organized thrombi were partially recanalized and surrounded and invaded by hyperplastic tissues from pulmonary artery wall. CONCLUSIONS: A canine model mimicking chronic PTE can be established by the use of fibrinolytic inhibitor tranexamic acid. Different manifestations on pulmonary arteriography and varied degree of organization of thrombi are evident at different times after embolization.

Angiography↗
PubMed1991

Umbilical cord blood gases and mortality and morbidity in the very low birth weight infant.

Umbilical cord blood gas values and morbidity and mortality were correlated in 191 very low birth weight (VLBW) infants (500-1500 g). The mean umbilical arterial pH and base excess differed significantly between survivors and non-survivors. The presence of at least moderate acidosis (arterial pH 7.15 or lower) was related significantly to mortality, particularly in infants younger than 26 weeks. The mean cord blood gas values did not predict the presence or severity of hyaline membrane disease or intraventricular hemorrhage, but Apgar scores did. Bronchopulmonary dysplasia, neurologic sequelae, necrotizing enterocolitis, and sepsis also did not correlate with mean cord gas values, but neither did Apgar scores. Furthermore, the severity and type of acidosis did not relate to morbidity. Combining cord blood gases and Apgar scores did not help predict morbidity, which was not surprising because cord pH values correlated poorly with Apgar scores (all r values less than or equal to 0.26). We urge caution in interpreting cord gases as predictors of morbidity in the VLBW infant.

Acidosis↗
PubMedDate not supplied

[A computer program for the interpretation of the acid-base status and respiratory gases].

A computer program for analysing the parameters of the acid-base status and respiratory gases has been designed. The program separates cases which are included into classical picture of certain respiratory, metabolic and mixed disorders. Out of a test series of 200 findings, 93% findings have been accurately interpreted. The program is written in BASIC, translated into machine code and occupies about 25 Kbyte computer memory. The main parts of the program use commands which do not favorize any version of BASIC increasing the program portability to other systems. The classification of respiratory gases and acid-base status was based on the already known facts.

Acid-Base Equilibrium↗
PubMedDate not supplied

[Effect of replacement of air nitrogen by inert gases on oxygen consumption by the liver tissues in albino rats on various fatty diets].

The effects of helium and argon, inert gases, on oxygen consumption have been studied on liver tissue of white rats who were delivered different fatty products plus to basic food). It is shown that the effects of helium and argon on the tissue respiration depend on the nature of fatty products. The role of membrane structure in realization of the influence of inert gases on tissue respiration is under discussion.

Animals↗
PubMed1989

[Clinical study on hemodynamics, blood gases and hemorheologic monitoring of patients with cor pulmonale].

14 patients of cor pulmonale in convalescent stage were studied with Swan-ganze catheter technique. The pulmonary arterial pressure, cardiac output, arterial blood gases, transcutaneous gases tension and hemorrheologic measurement were monitored simultaneously at definite intervals within 24 hours. The results showed that the mean value of the pulmonary arterial pressure (MPAP), arterial carbon dioxide tension (PaCO2), transcutaneous carbon dioxide tension (tcPCO2), hematocrit(H), whole blood viscosity (eta b) and plasma viscosity (eta p) were higher at night than those at daytime. While the value of cardiac output (CO), arterial oxygen tension (PaO2) and transcutaneous oxygen tension (tcPO2) showed a converse result, most of them showed more predominant at daytime and tended to be lowered at night. The MPAP in some of convalescent patients might decrease to normal, but in the pulmonary hypertension group [MPAP greater than or equal to 2.66 Kpa (20 mmHg)] the day and night measurements of MPAP, CO, PaO2, PaCO2, tcPO2, tcPCO2 were fluctuate more obviously than in normal group (P less than 0.01). The day and night hemorrheologic measurements such as H, eta b, eta p etc. showed that the blood viscosity increased more significantly at night than at daytime. The cardiac output (CO, CI) seemed to be a little bit lower in some patients especially in those with high pulmonary arterial pressure and at night. These results suggest that the variation of the day and night measurements of hemodynamics, blood gas, hemorrheologic changes have some rule.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

[CFC gases in medicinal sprays].

In 1987, approximately 1.18 million aerosol dispensers for medicinal use were sold in Denmark. These contained approximately 29 tons of completely halogenized CFC gases ("Freon") and the preparations were employed for the treatment of bronchial asthma and rhinitis. The possibilities of substitutes are discussed in this article. Preparations are already available which do not contain CFC. Producers of CFC are also attempting to develop new aerosol gases which do not damage the environment. Perhaps these will be found in medicinal preparations in the future.

Aerosols↗
PubMed1989

[Invasive monitoring of arterial gases in intensive care. Indications, misuse and hazards].

Although arterial blood gas analysis remains the "gold standard" for oxygen (O2) and carbon dioxide (CO2) measurements during critical illness, several new techniques are now available for clinicians in this field, i.e. pulse oximetry, transcutaneous (PtcO2) and transconjunctival (PcjO2) O2 monitoring, CO2 continuous measurements in expired gases (capnography) and transcutaneous PCO2 (PtcCO2). While it seems too early to assign a definite role to all these techniques in the management of critically ill patients, several points can be emphasized: 1. pulse oximetry is a cheap, versatile device for monitoring of nonhypoxemic patients; 2. PtcO2 is a good index of poor skin oxygenation and is related to PaO2, but this index should be interpreted with caution in unsteady patients; perhaps its main value is as an early warning that "something is wrong with the patient". PcjO2 may be promising, but more data are needed; 3. PtcCO2 and capnography seem more suitable for research purposes or for patient monitoring in the operating theatre. Finally, it should be emphasized that invasive arterial blood gas measurements using an indwelliing arterial catheter are safe and provide with the best possible acid-base and hemodynamic monitoring. Noncontinuous monitoring of blood gases and, perhaps, the delay between arterial puncture and completion of the analysis seem to be the only drawbacks of this technique.

Blood Gas Analysis↗
PubMed1979

Blood volume and arterial blood gases in patients with chronic obstructive lung disease during and after acute respiratory failure.

The blood volume and arterial blood gases of 18 patients with chronic obstructive lung disease were studied over a period of 1/2 to 5 years, including 35 acute exacerbations of the lung disease. Treatment during exacerbation was directed at infection, bronchial obstruction and hypervolemia. Long-term diuretic therapy was instituted during the follow-up period. On admission all patients suffered from severe dyspnoea, all but two had signs of peripheral oedema and/or liver congestion and one-third had increased jugular venous pressure. Blood volume was increased in all patients and eight of them had a hematocrit above 50%. PaCO2 was severely reduced and PaCO2 increased on admission. At discharge, these symptoms and signs had all diminished or disappeared. Blood volume had fallen an average of 11 and a further reduction of 0.41 was noticed during the follow-up period. Blood gases had improved by discharge and a further improvement accompanied the reduction of blood volume during the follow-up period. It is suggested that 1) hypervolemia is common in patients with advanced chronic obstructive lung disease; 2) hypervolemia may impair arterial oxygenation; 3) long-term diuretic therapy seems to be necessary for maintaining a normal blood volume.

Adult↗
PubMed1979

[Effect of almitrine on arterial gases in patients with chronic respiratory insufficiency. Comparison with doxapram. Preliminary results].

We compared the effects of almitrine and doxapram on the arterial blood gases and ventilation of patients with chronic respiratory insufficiency and chronic hypercapnia and hypoxemia. Sixteen long-term in-patients were randomly allocated to one of the following treatment groups: the first group (8 patients) received IV almitrine 0.5 mg/kg and the second group (8 patients) IV doxapram 1 mg/kg by IV perfusion during 30 min. All gave their informed consent. Arterial blood gases and ventilation were measured 10 min and 5 min before treatment, at the 5th, 15th and 25th min of perfusion time, and 5, 10 and 15 min after infusion. There was a marked increase in paO2 in almitrine-treated patients, which was maximum at the 25th min of infusion (+ 14.6 mm Hg, p < 0.001), but only a slight improvement was observed in the doxapram group (+ 3.3 mm Hg, p < 0.05). After almitrine the maximum mean paCO2 decrease was at the 10th min after perfusion (-6.9 mm Hg, p < 0.001); after doxapram the maximum decrease, although highly significant, was much less (-2.8 mm Hg, p < 0.01). Thus, at the presently used and well-tolerated doses, almitrine is much more efficient than doxapram in improving gas exchange in patients with chronic hypoxemia and hypercapnia. However, complementary studies using higher dosage of doxapram are warranted.

Aged↗
PubMedDate not supplied

[A rotative control plate for separation of inspired and expired gases (author's transl)].

Some drawbacks of the valve chamber are well known: high flow gas resistance, sensitivity to position and to condensation of water vapour, vibrations of the valve especially at high flow rate. To avoid these defects a rotative control valve separating inhaled and exhaled gases is described. A rotative plate shuts off one of two large ports and separates expired and inspired gases. The rotation of the plate is controlled by a sensor signal, which may be delivered by a pneumotachograph and switches on and off the electrical supply of the motor. The major characteristics of this valve are: its small dead space (11 cm3), a negligible error in the volumes which are to be displaced through either of the two ports, a total insensitivity to water condensation, a very low flow resistance and an insensitivity to position and displacement. This device may be adapted to infants and neonates.

Humans↗
PubMed1983

Anesthetic waste gases in veterinary medicine: analysis of the problem and suggested guidelines for reducing personnel exposures.

Anesthetic waste gases are a concern to veterinarians and their personnel. Investigations have shown that many of the anesthetic units used in veterinary medicine have leaks that contribute to operating room contamination. Many others do not have appropriate scavanging attachments to remove escaping gases. Personnel were frequently observed carelessly using equipment or handling anesthetic agents in a manner contributing to excessive exposure. Proper maintenance of equipment and careful use of gaseous anesthetic agents can significantly reduce waste gas levels and exposure of personnel.

Air Pollutants, Occupational↗
PubMed1980

[The effect of epidural analgesia during labour on the blood gases and acid-base balance (author's transl)].

The effect of epidural analgesia on the blood gases and acid-base balance was studied in 20 women during labour and in the newborn. The measurements were taken during the early first stage, the second and forth stage and in the newborns immediately post partum. 20 women in labour who had not been given epidural analgesia served as a control group. The values for the blood gases and the acid balance were less affected in women who had epidural analgesia, but the incidence of deliveries requiring vaginal operations was higher.

Acid-Base Equilibrium↗