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PubMed2000

Non-traumatic gas gangrene in the abdomen: report of six autopsy cases.

Six autopsy cases of non-traumatic gas gangrene in the abdomen are reported. Five of the six were caused by clostridia, as identified by culture or histology. There were associated underlying diseases, such as alcoholism, liver cirrhosis, diabetes mellitus, and malignant disease. Three of the six patients had gas gangrene in the liver. Bacterial proliferation and gas accumulation were found in the sinusoids of the liver, and congestion and edema with extensive gas embolism were found in the lungs. Pulmonary gas embolism was considered to be the direct cause of death in these three patients. The other three patients had intestinal clostridial gas gangrene, with alcoholism as an underlying condition. None of the six patients was clinically diagnosed as having gas gangrene. We suggest that gas gangrene should be considered in any patient with abdominal infection. A review of 19 autopsy cases of gas gangrene in the abdomen reported in the Japanese literature is also presented.

Abdomen↗
PubMed1997

Carbon dioxide and oxygen partial pressure measurements in the cerebrospinal fluid in a conventional blood gas analyzer: analysis of bias and precision.

Cerebrospinal fluid (CSF) gas tension measurements have been used as a marker of cerebral oxygenation in animal models and in human studies. Discrepancies in the measurement of PCO2 and PO2 in non-blood solutions by standard blood gas analyzers have been described. The CSF is a physiological non-blood fluid with an ability to carry only dissolved O2 or CO2. The aim of this experiment was to determine the bias and precision of CSF pCO2 and pO2 measurements of a contemporary blood gas analyzer and a continuous gas sensor. CSF from human patients was tonometered to known PCO2 and PO2 using standard calibration gases in a bubble tonometer. Following equilibration, a continuous measurement of the partial pressure of gases in the CSF in the tonometer solution was made using a calibrated Paratrend 7 gas sensor (Biomedical Sensors, Bucks., UK) inserted into the equilibration chamber of the tonometer and continuous CSF pH, PCO2 and PO2 measurements recorded at 1-min intervals. After equilibration, a 3-ml CSF sample was aspirated anaerobically from the tonometer and analysed in duplicate using an ABL 620 (Radiometer, Copenhagen) blood gas analyser. The measured pCO2 and pO2 from the ABL 620 blood gas analyser and the Paratrend 7 sensor were paired with the expected values to calculate bias and precision. Small offsets in PCO2 and large offsets in PO2 measurement were seen with the ABL 620 blood gas analyser. This study brings into question clinical decisions based on CSF PO2 measurements. The implications for calibrating CSF sensors against CSF gas measurements are discussed.

Blood Gas Analysis↗
PubMed2002

The automatic lung parameter estimator (ALPE) system: non-invasive estimation of pulmonary gas exchange parameters in 10-15 minutes.

OBJECTIVE: Clinical measurements of pulmonary gas exchange abnormalities might help prevent hypoxaemia and be useful in monitoring the effects of therapy. In clinical practice single parameters are often used to describe the abnormality e.g., the "effective shunt." A single parameter description is often insufficient, lumping the effects of several abnormalities. A more detailed picture can be obtained from experiments where FiO2 is varied and two parameters estimated. These experiments have previously taken 30-40 minutes to complete, making them inappropriate for routine clinical use. However with automation of data collection and parameter estimation, the experimental time can be reduced to 10-15 minutes. METHODS: A system has been built for non-invasive, Automatic, Lung Parameter Estimation (ALPE). This system consists of a ventilator, a gas analyser with pulse oximeter, and a computer. Computer programs control the experimental procedure, collect data from the ventilator and gas analyser, and estimate pulmonary gas exchange parameters. Use of the ALPE system, i.e. in estimating gas exchange parameters and reducing experimental time, has been tested on five normal subjects, two patients before and during diuretic therapy, and on 50 occasions in patients before and after surgical intervention. RESULTS: The ALPE system provides estimation of pulmonary gas exchange parameters from a simple, clinical, non-invasive procedure, automatically and quickly. For normal subjects and in patients receiving diuretic therapy, data collection by clinicians familiar with ALPE took (mean +/- SD) 13 min 40 sec +/- 1 min 23 sec. For studies on patients before and after surgery, data collection by an intensive care nurse took (mean +/- SD) 10 min 47 sec +/- 2 min 14 sec. Parameter estimates were: for normal subjects, shunt = 4.95% +/- 2.64% and fA2 = 0.89 +/- 0.01; for patients with heart failure prior to diuretic therapy, patient 1, shunt = 11.50% fA2 = 0.41, patient 2 shunt = 11.61% fA2 = 0.55; and during therapy: patient 1, shunt = 11.51% fA2 = 0.71, patient 2, shunt = 11.22% fA2 = 0.49. CONCLUSIONS: The ALPE system provides quick, non-invasive estimation of pulmonary gas exchange parameters and may have several clinical applications. These include, monitoring pulmonary gas exchange abnormalities in the ICU, assessing post-operative gas exchange abnormalities, and titrating diuretic therapy in patients with heart failure.

Diuretics↗
PubMed1991

[Sonographic detection of gas in the vascular system of the liver: an image essay].

Gas within the vascular system of the liver was demonstrated sonographically in 5 patients. In contrast, plain films of the abdomen in these patients failed to demonstrate this serious finding. 3 patients presented with gas within the hepatic portal venous system, 1 patient with gas in the liver veins. In these patients, gas formation was probably caused by sepsis with gas-producing bacteria. In the last patient, air within the hepatic arterial system was caused by insufflation of air thru a port-a-cath catheter located in the main hepatic artery. The characteristic sonographic appearance of intravascular gas are highly echogenic particles flowing within the vessels. Different pathophysiologic mechanisms of gas formation in the hepatic portal venous system include sepsis with gas forming organisms, gastrointestinal necrosis of various origin in combination with elevation of intramural pressure and alteration of gas solubility of blood. The significance of sonography as a very sensitive and specific modality is outlined.

Adult↗
PubMed1998

Substantial changes in arterial blood gases during thoracoscopic surgery can be missed by conventional intermittent laboratory blood gas analyses.

UNLABELLED: Substantial and clinically relevant changes in arterial blood gases are likely to occur during thoracoscopic surgery with one-lung ventilation (OLV). We hypothesized that they may be missed when using the conventional intermittent blood gas sampling practice. Therefore, during 30 thoracoscopic procedures with OLV, the sampling intervals between consecutive intermittent laboratory blood gas analyses (BGA) were evaluated with respect to changes of PaO2, PaCO2, and pHa ([H+]) using a continuous intraarterial blood gas monitoring system. Frequency and timing of BGA were based on the clinical judgment of 16 experienced anesthesiologists who were blinded to the continuously measured values. Extreme fluctuations of PaO2 (37-625 mm Hg), PaCO2 (27-56 mm Hg), and pHa (7.24-7.51) were observed by continuous blood gas monitoring. During 63% of all sampling intervals, PaO2 decreased >20% compared with the preceding BGA value, which remained undetected by intermittent analysis. In 10 patients with a continuously measured minimal PaO2 value < or = 60 mm Hg, the preceding BGA overestimated this minimal PaO2 by > 47%. Correspondingly, PaCO2 increases of > 10% were observed in 35% of all sampling intervals, and [H+] increases of > 10% were observed in 24% of all sampling intervals. Because these blood gas changes were not reliably detected by using noninvasive monitoring and their magnitude is not predictable during OLV, intermittent BGA with short sampling intervals is warranted. In critical cases, continuous blood gas monitoring may be helpful. IMPLICATIONS: The magnitude of blood gas changes during thoracoscopic surgery with one-lung ventilation is not predictable and not reliably detected by noninvasive monitoring. Using a continuous intraarterial blood gas monitoring device, we demonstrated that intermittent laboratory blood gas analysis with short sampling intervals is warranted to detect arterial hypoxemia.

Adolescent↗
PubMed1993

Initial evaluation of a new intra-arterial blood gas system in humans.

OBJECTIVE: To evaluate the in vivo performance of a continuous intra-arterial blood gas monitor as compared with in vitro arterial blood gases for measurements of PaO2, PaCO2, and arterial pH. DESIGN: Consecutive patient enrollment. SETTING: Medical intensive care unit of a county teaching hospital. PATIENTS: Five critically ill patients. INTERVENTIONS: All patients had a fiberoptic sensor placed through a 20-gauge cannula inserted into the radial artery. Sensor and arterial blood gas measurements were monitored up to 68 hrs. Arterial blood gases were analyzed on two blood gas analyzers. MEASUREMENTS AND MAIN RESULTS: A total of 104 arterial blood gases were obtained for comparison of sensor measurements with blood gas analyzer values. Comparison of the sensor values with the blood gas analyzer values showed bias and precision values of -0.021 and 0.037 for arterial pH, 1.74 and 6.06 torr (0.23 and 0.81 kPa) for PaCO2, and -5.89 and 13.19 torr (-0.79 and 1.76 kPa) for PaO2, respectively. Comparison of the two blood gas analyzer measurements showed bias and precision values of -0.030 and 0.010 for arterial pH, 1.96 and 2.55 torr (0.26 and 0.34 kPa) for PaCO2, and -5.77 and 17.15 torr (-0.77 and 2.29 kPa) for PaO2, respectively. No complications attributable to the sensor were detected. CONCLUSIONS: The performance of this fiberoptic continuous intra-arterial blood gas monitor is comparable to that of blood gas analyzers and compares favorably with previously reported studies utilizing other sensors in reliably and reproducibly approximating PaO2, PaCO2, and arterial pH values. This monitoring capability was accomplished with no patient morbidity. Further study is indicated to confirm these initial results and to establish the role of a continuous intra-arterial blood gas monitor in critically ill patients.

Adult↗
PubMed1996

Sweep gas flowrate and CO2 exchange in artificial lungs.

A simple analysis and graphic result are presented for characterizing the dependence of CO2 exchange on the sweep gas (ventilating gas) flowrate in artificial lungs. The analysis requires no knowledge of the device-specific mass transfer characteristics of an artificial lung, nor does it require detailed mathematical modeling or computer simulation. Rather, it uses appropriate normalization to establish generic features of the gas flow dependency of CO2 exchange that are applicable to all artificial lung devices. Principal results are that the transition from relatively gas flow-sensitive to gas flow-insensitive CO2 exchange occurs at sweep gas flowrates of approximately 40-60 times the CO2 exchange rate. Achieving a CO2 exchange rate within 85% of maximal (for a given oxygenator and blood-side conditions) requires a sweep gas flowrate of no less than approximately 50 times the nominal CO2 exchange rate. When the sweep gas flowrate is less than 20 times the CO2 exchange rate, CO2 exchange is highly gas flow dependent and less than one-half the maximal possible rate.

Artificial Organs↗
PubMed1995

Blood gas monitors.

In vitro blood gas analysis requires limitation of the frequency of serial blood gas measurements for two major reasons--blood loss and cost. In vivo or ex vivo blood gas monitors eliminate these factors because the measurements are available continuously, or as frequently as deemed desirable, without permanently removing blood or imparting additional cost. For patients with arterial catheters in place, the propriety of blood gas monitors is obvious as long as there is no requirement to alter the size, location, or placement of the arterial catheter and the routine use of the arterial catheter system is unaffected. Further, personnel exposure to the patient's blood, and the risk of nosocomial infection from contaminated arterial catheters, should be reduced because the integrity of the arterial catheter and tubing system is not interrupted to obtain blood gas values. Blood gas monitors and point-of-care analyzers should significantly reduce therapeutic decision time (the interval from ordering the test to initiating a therapeutic action based on the test results), thereby enabling rapid titration of common therapeutic modalities such as oxygen administration, positive pressure ventilation, positive end-expiratory pressure, and manipulation of acid-base balance. The transfer of blood gas measurements from laboratory analyzers to the combination of blood gas monitors and point-of-care analyzers should have as profound an impact on acute care medicine as did the introduction of laboratory-based blood gas analysis over 30 years ago. In the current medico-economic environment, however, we must be certain that these devices are reliable, consistent, and cost beneficial in order to avoid widespread application of yet another technology that provides more data, greater costs, and only questionable patient benefits.

Blood Gas Analysis↗
PubMed1986

Determination of permeabilities for two gases from recording the partial pressure of one gas.

When a flexible diffusion layer separates two closed gas chambers containing different mixtures of several gases, the different permeabilities of the layer for these gases lead to differences in the total gas pressures of the two chambers resulting in bulging of the layer and consequent changes in the chamber volumes. Application of the gas laws to binary gas mixtures provides two equations relating the partial pressure changes of one gas in any of the two chambers to the partial pressure difference between the two chambers across the layer. This permits the calculation of the two unknown factors, permeability (or Krogh's diffusion coefficient) of the layer for the measured gas and the permeability ratio of the two gases. Thus the permeabilities of both gases can be determined from recording the partial pressure of one of the gases only. We filled the gas chambers with different mixtures of oxygen and a second gas (nitrogen or carbon dioxide) at atmospheric pressure, closed the chambers, and measured the diffusion of the gases across thin (12-500 microns) layers of various materials by recording the oxygen partial pressure in both chambers with polarographic oxygen electrodes. Permeabilities of these layers for oxygen and the other gas were determined for plastic layers (MEM213, Silastic, Teflon), as well as water and methemoglobin solutions either in a fluid layer or soaked in Millipore filters. The data agreed well with those obtained from other studies in most cases.

Gases↗
PubMed2000

Postoperative intra-abdominal free gas after open colorectal resection.

PURPOSE: An erect chest radiograph for subdiaphragmatic free gas can be a useful adjunct in detecting a defect in gastrointestinal continuity. The usefulness of this test after laparotomy has not been defined, because the period of persistence of free gas is unknown. We set out to determine the length of time for natural absorption of postlaparotomy pneumoperitoneum in a prospective cohort study. METHOD: Plain erect chest radiographs were performed on the second and fourth postoperative day and daily thereafter until the disappearance of subdiaphragmatic free gas after laparotomy. RESULTS: Seventy-five consecutive patients were studied after informed consent. The mean age was 62.1 (standard error of the mean, 1.7) years. On the fifth postoperative day, sixth postoperative day, and seventh postoperative day, 71.6, 80, and 89 percent of patients, respectively, had no visible subdiaphragmatic gas. Five patients had gas persisting beyond the tenth postoperative day. Two of these patients did not have an anastomosis. The use of drainage tubes did not affect significantly the mean time to disappearance of subdiaphragmatic free gas (4.5 vs. 4.9 days; P = 0.45: t-test). The duration of surgery, body mass index, and time to resume bowel function had no significant effect on gas disappearance. Two patients had a clinical leak on the fifth postoperative day. This was manifested as an increase in the collection of subdiaphragmatic gas during the course of a day. CONCLUSION: By the sixth postoperative day 80 percent of patients had no subdiaphragmatic free gas on an erect chest radiograph regardless of the presence of a drainage tube. The erect chest radiograph may therefore be a simple and readily available adjunct in the evaluation of postoperative abdominal pain, especially after the sixth postoperative day when a similar prior examination is done routinely on the fourth postoperative day for comparison.

Anastomosis, Surgical↗
PubMed1997

The characterization of the nv-gvpACNOFGH gene cluster involved in gas vesicle formation in Natronobacterium vacuolatum.

The haloalkaliphilic archaeon Natronobacterium vacuolatum forms cylinder-shaped gas vesicles throughout the growth cycle when grown in media containing 15-25% NaCl. Cells cultivated in media containing 13% NaCl are, however, gas-vesicle-free. The major gas vesicle structural protein, nv-GvpA, was detected by an antiserum raised against the gas vesicles of Haloferax mediterranei; the antiserum reacted with an 8.3-kDa protein in samples containing cell extracts or purified gas vesicles of N. vacuolatum. The gene encoding nv-GvpA was isolated together with six additional gvp genes; these genes are arranged consecutively in a cluster as nv-gvpACNOFGH and are cotranscribed. Transcript analysis by primer extension revealed only one start site three nucleotides upstream of the nv-gvpA reading frame. This arrangement of gvp genes differs from that of the gas-vesicle-encoding genes in Halobacterium salinarium and Hf. mediterranei. The comparison of the deduced Gvp protein sequences indicated similarities with the respective halobacterial Gvp proteins, with GvpA exhibiting the highest degree of conservation (97-100%). The second gas vesicle structural protein, nv-GvpC, was 150-250 amino acids longer than all other halobacterial GvpC proteins and was much less conserved (48-73%). The expression of the nv-gvp genes was monitored in N. vacuolatum cells cultivated in 20 or 13% salt media. Northern and Western analyses showed that despite the lack of gas vesicles in cells grown in 13% salt medium, the gvpACNOFGH gene cluster was transcribed and GvpA protein was synthesized, suggesting that the absence of gas vesicles is not due to a lack of transcription.

Amino Acid Sequence↗
PubMed2005

Bloating and intestinal gas.

The most common symptoms associated with intestinal gas are eructation, flatulence, abdominal bloating, and distention. Aerophagia is an uncommon cause of eructation in which repetitive air swallowing results in belching, abdominal distention, and increased flatus. Few therapies have been shown to be effective in treating these symptoms. Eructation can be treated by decreasing excessive air swallowing. Occasionally, behavioral therapy and psychotherapy are employed. Bloating, distention, and other gas-related symptoms are common in functional gastrointestinal disorders; however, their pathophysiology is poorly understood. Additionally, evidence supporting the use of various available therapies in treating gas-related symptoms is either absent or poor. Dietary therapy may be effective in patients with excessive gas production. Excessive gas production, identified by increased flatus, may benefit from a low-carbohydrate diet. Many patients with gas-related symptoms have normal gas production but may have either impaired gas transport or transit through the gut or visceral hypersensitivity. Few studies have addressed the treatment of impaired gas transport.

Journal Article↗
PubMed1991

Percutaneous coronary and peripheral angioscopy with saline solution and carbon dioxide gas in porcine and canine arteries.

To obtain a clear view with angioscopy, blood must be displaced. Carbon dioxide (CO2) gas has proved to be a safe intraarterial contrast agent, and it may have advantages over saline solution as an infusion medium for angioscopy. This study compared the use of CO2 gas and saline solution in the femoral artery, in the presence and absence of a proximal occlusion, in nine pigs and six dogs. The applicability of CO2 gas in the coronary arteries was also evaluated. In total 185 angioscopy procedures were evaluated. With proximal occlusion, angioscopy with CO2 gas was successful in all 28 peripheral procedures, whereas with saline solution only 65% of the procedures resulted in a clear view (p less than 0.005). Without proximal occlusion, angioscopy was successful with CO2 gas and saline solution in 61% and 3% of procedures, respectively (p less than 0.0001). Cardiovascular parameters and blood gases showed minor changes after administration of CO2 gas. During coronary angioscopy with CO2 gas, mechanical heart failure occurred in all instances, which was lethal in 12 animals. None of the animals died as a result of saline angioscopy. In conclusion, CO2 gas is a safe medium for angioscopy in the peripheral arteries and in general offers a better view than saline solution. In contrast to saline solution, without proximal balloon occlusion CO2 gas provided a clear view in 61% of the peripheral procedures. In the coronary arteries, however, CO2 angioscopy was generally fatal in both animal models.

Animals↗
PubMed1976

Ternary gas diffusion - in vitro studies.

The purpose of these experiments was to compare diffusive gas movement in a two-gas system with that in a three-gas system. Gas mixtures of different compositions were placed initially on either side of a removable partition dividing a cylindrical lucite diffusion chamber, filled with 3 mm glass beads. This served to slow diffusion, minimize convective currents generated by removing the partition, and stabilize temperature within the chamber. In two-gas systems, after the partition was removed, oxygen equilibrated between the two parts of the chamber more rapidly in a helium environment than in a nitrogen environment, conforming with predictions based on binary gas laws. Results obtained with a three-gas system differed significantly from those obtained with the binary system. With 21% oxygen in belium initially in one half of the chamber and 21% oxygen in nitrogen in the other, PO2 rose transiently in the He-O2 side of the chamber. Qualitatively, similar results were obtained when the O2-N2 mixture was replaced by 100% nitrogen. Pressure in the system remained essentially constant. The possible mechanisms responsible for the PO2 rise were studied using a computer model of the system. This showed that movement of a given gas may be affected significantly by movement of other gases in the system. Hence, application of binary gas diffusion laws to systems containing more than two gases may lead to significant errors.

Diffusion↗
PubMed1980

Effect of lower body negative pressure release on hyperpnea induced by inhaled gas.

Transient breath-by-breath ventilation (VI) and end-tidal gases were measured on 6 men in response to: (1) the release of lower body negative pressure (LBR); (2) the one-min inhalation of a gas mixture (GAS) containing 5.4% CO2, 14% O2, balance N2; (3) the two combined (LBR + GAS) with LBR preceding GAS inspiration by 5 sec. With LBR a + 29% peak response in VI occurred after 20 sec whereas with GAS and LBR + GAS, VI tended to level off after 25 sec at + 100% and + 180%, respectively. Simultaneously, PETCO2 had risen 2, 5 and 8 mm Hg and PETO2 had fallen 7, 14 and 19 mm Hg, respectively. LBR accelerated and potentiated the VI response to GAS. Leg volume indicated that 50% of the pooled blood returned from the legs after 4 sec, presumably with high PCO2 and low PO2 contributing an endogenous respiratory stimulus to the exogenous one of GAS. VI with LBR + GAS was greater than the sum of each, suggesting an enhancement of the chemoreceptor response by returning pooled blood.

Adult↗
PubMed1980

Incomplete gas mixing in air sacs of the duck.

During normal breathing, the CO2 concentration in caudal air sacs of birds is higher, and the O2 concentration lower, than expected on the basis of the known air flow pattern. We have experimentally tested two hypotheses which could explain this finding: (1) Preferential shunting of re-inspired dead space gas into caudal air sacs; (2) Incomplete mixing of inspired and residential air sac gas. - Different portions of the inspired air in anesthetized ducks were labeled by injecting a small bolus of argon (Ar) into the trachea. The resulting Ar concentration was recorded continuously in the caudal thoracic air sac at the ostium and in deeper regions.-The amount of Ar entering the sac was found to be independent of the volume inspired prior to injection of the label, and hypothesis (1) thus dismissed. However, during inspiration and subsequent expiration the Ar bolus was found to be neither perfectly mixed within the inspired gas nor with the air sac residential gas. More than 10 sec of breath-hold were necessary for air sac gas to approach an equilibrium value. Gas layering (stratification) in caudal air sacs gas is proposed to cause the high CO2 and low O2 levels during steady state breathing, as air sac residential gas equilibrates with a layer of dead space gas that enters the air sac on each breath and contains a higher CO2 and lower O2 concentration than the mixed inspirate.

Animals↗
PubMed1987

Inspiratory aerodynamic valving in goose lungs depends on gas density and velocity.

The non-reversing gas flow pattern in the avian lung has been attributed to 'aerodynamic valves'. A fundamental property of all aerodynamic valves is their dependence on inertial forces in the gas stream: sufficient reduction of inertial forces will cause aerodynamic valves to fail. If valving in the avian lung is aerodynamic, it should fail when gas stream momentum is reduced. We tested the dependence of the inspiratory valves in the goose lung on gas density and gas flow velocity. A bolus of tracer gas was placed in the tracheal cannula during an end-expiratory pause. Tracer gas appearance in a cranial air sac during the following inspiration and pause was used to deduce failure of the 'inspiratory valve' in cyclically ventilated geese. Little or no tracer entered the sac under control conditions, which approximated resting breathing, indicating highly effective valving. Lower flow rate or lower gas density caused increased tracer appearance, indicating valve failure. These results demonstrate the importance of gas inertial forces to normal valve function, and are direct evidence for the aerodynamic nature of the avian inspiratory valve.

Animals↗
PubMed1988

Relative participation of the gas phase and total particulate matter in the imbalance in prostacyclin and thromboxane formation seen following chronic cigarette smoke exposure.

Chronic exposure to cigarette smoke causes an imbalance in the ratio of PGI2 and TXA2 production and is believed to favor the development of atherosclerosis. Components of the particulate phase of smoke (especially nicotine) as well as the gas phase of smoke have been shown to adversely alter arachidonic acid metabolism. To determine the relative participation of nicotine, particulate and gas phases in eliciting an imbalance in TXA2 formation, male Sprague-Dawley rats were chronically exposed (7 days/wk/mo.) to freshly generated whole smoke or gas phase from University of Kentucky Reference cigarettes and allowed access to regular drinking water or to water supplemented with nicotine (10 micrograms/ml). COHb levels were monitored to confirm smoke or gas phase inhalation. All treatment groups had lower body weights than shams. No differences in body weights were observed between smoke (+/- oral nicotine) and gas phase (+/- oral nicotine) treatment groups but all were significantly lower than oral nicotine treated animals. Platelet TXA2 production was elevated in all treatment groups compared to shams. No differences in TXA2 production were observed between smoke (+/- oral nicotine), gas phase and oral nicotine treated animals. Animals receiving gas phase/oral nicotine exhibited significantly higher platelet TXA2 production compared to the other treatments. Constituents of the gas phase as well as the particulate phase of whole smoke were both shown to elevate platelet TXA2 formation. Components of the particulate matter appear to modulate the effects of nicotine and the gas phase in the perturbation of TXA2 production in the rat smoking model.

Animals↗