Changes In Cardiopulmonary Function Research Articles

Changes in cardiopulmonary variables and platelet count during anesthesia for total hip replacement in dogs.

Changes in cardiopulmonary function and platelet count were determined in 22 dogs of various breeds that underwent total hip replacement with cemented femoral prostheses. In 11 dogs (group I) polymethylmethacrylate (PMMA) was inserted without venting the reamed and lavaged femoral canal. In a second group of 11 dogs (group II) a urethral catheter (ID: approximately 2.7 mm) was placed into the medullary cavity before the insertion of PMMA. The application of PMMA resulted in a decrease in end-tidal carbon dioxide tension (PETCO2) until 5 minutes after insertion of bone cement. Increases in arterial to end-tidal pCO2 gradient [P(a-ET)CO2] and physiological dead space (VD/VT) were recorded between 2 minutes before and 5 minutes after insertion of PMMA in 12 dogs. A significant decrease in platelet count occurred in both groups of dogs. Decreases in arterial pO2 (PaO2), arterial/alveolar oxygen tension ratio (PaO2/PAO2), and percent O2 saturation of hemoglobin in arterial blood (SaO2) were not statistically significant. No significant differences could be detected between data obtained from both groups of dogs. An increase in femoral intramedullary pressure caused by the insertion of PMMA and subsequent pulmonary microembolism by medullary contents has been considered the most likely cause for changes in pulmonary function. The lack of statistically significant differences in cardiopulmonary variables and platelet count between the two groups of dogs could have been related to inefficient pressure reduction by the method used.

Postoperative ventilation: a goal-directed approach?

After every operation, the anaesthetist makes a decision as to whether his/ber patient requires or would benefit from mechanical ventilatory support. In high-risk patients, this decision is considered preoperatively; however, intraoperative events can mandate a re-assessment of the need for postoperative ventilation. The assumption is often made that ventilation can prevent postoperative respiratory complications. Yet, there is no evidence that temporary ventilatory support, as a routine measure, prevents atelectasis or pneumonia. In fact, some reviewers suggest that the opposite may be true. The decision to provide postoperative ventilation often initiates the admission to an intensive care unit (ICU) with comprehensive monitoring and nursing care. This decision, therefore, initiates the use of other technologies and resources. Routine postoperative ventilation can resuit in the use of ICU care by default, based on convenience rather than physiological need. As many as 30% of surgical ICU admissions 2,3 require monitoring only with no life-threatening events. Large discrepancies in the use of ICU interventions for similar postoperative patients suggests that a re-evahiation of critical care utilization is required.4 No one questions that there are benefits of postoperative positive pressure ventilation (PPV) for appropriately selected patients. However, the risks and benefits are yet to be determined. 5,6 The challenge is to select appropriate patients and to tailor the intraoperative management to the anticipated postoperative needs. This review will focus on indications for postoperative ventilation based on physiological principles .and current understanding of postoperative respiratory physiology. Based on a thorough preoperative assessment and an understanding of intraoperative and anticipated postoperative changes in cardiopulmonary function, the clinician's goals should focus on correcting reversible components of postoperative respiratory dysfunction. Weaning and extubation follow.

LEFT VENTRICULAR DYSFUNCTION AND ACUTE LUNG INJURY INDUCED BY CONTINUOUS ADMINISTRATION OF ENDOTOXIN IN SHEEP

Sixteen sheep were surgically prepared for chronic study. Seven days later, Escherichia coli endotoxin (10 ng/kg/min, lipopolysaccharide (LPS) group, n = 10) or an equivalent amount of 0.9% NaCl (Control group n = 6) was administered. Between 1 and 8 h post-LPS, there was a hypodynamic state with low cardiac index (CI, LPS 5.0 +/- 0.2; sham 6.3 +/- 0.4 liters/min/m2 at 4 h). During this period, the left ventricular end-systolic pressure-diameter relationship (ESPDR), a sensitive index of myocardial contractility, was also lower (LPS 10.4 +/- 1.2; sham 17.2 +/- 0.8 mmHg/mm). Mean pulmonary arterial pressure (PAP) and pulmonary vascular resistance index (PVRI) were remarkably increased 1 h after the administration of LPS (PAP:LPS 37.5 +/- 1.9; sham 21.8 +/- 0.9 mmHg, PVRI: LPS 600 +/- 58; sham 158 +/- 23 dynes x s x cm-5 x m2). The early changes in cardiopulmonary function occurred concomitantly with an elevation in tumor necrosis factor (LPS 1221 +/- 520; sham 0 +/- 0 pg/ml) and thromboxane B2 (LPS 1382 +/- 266; baseline 82 +/- 20 pg/ml) in arterial blood. Following this first phase, the sheep presented a persistent hyperdynamic state characterized by a significant increase in CI. The ESPDR continued to fall. By 24 h post-LPS the CI was 10.1 +/- 0.5 liters/min/m2 (sham, 6.3 +/- 0.3) but the ESPDR had fallen to 8.2 +/- 2.3 mmHg/mm (sham 16.0 +/- 3.0). The pulmonary hypertension was maintained for the duration of the LPS infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Time Course of Pulmonary Function Before Admission Into ICU: A Two-year Retrospective Study of COLD Patients with Hypercapnia

Changes in cardiopulmonary function were retrospectively evaluated back to two years before acute exacerbations requiring ICU admission in 16 COLD patients with chronic hypercapnic respiratory insufficiency (age: 61 +/- 6 years, group A). Fifteen hypercapnic COLD patients matched for age, sex, lung function, and blood gas values not requiring an ICU admission in a period of two years, served as control subjects (age: 66 +/- 7, group B). Periodic assessments of spirometry, arterial blood gas values, echocardiography, body weight, and red blood cell count performed in stable state were compared for differences between groups and changes over a period of two years. The results indicated that basal body weight, rate of deterioration over time in FEV1, VC, blood gas values, bicarbonates, and RVD may be related to the necessity of ICU admission in COLD patients with hypercapnic respiratory insufficiency.

Cardiopulmonary effects of etomidate in hypovolemic dogs

Summary Cardiopulmonary effects of etomidate administration were studied in hypovolemic dogs. Baseline cardiopulmonary data were recorded from conscious dogs after instrumentation. Hypovolemia was induced by withdrawal of blood from dogs until mean arterial pressure of 60 mm of Hg was achieved. Blood pressure was maintained at 60 mm of Hg for 1 hour, by further removal or replacement of blood. One milligram of etomidate/kg of body weight was then administered iv to 7 dogs, and the cardiopulmonary effects were measured 3, 15, 30, and 60 minutes later. After blood withdrawal and prior to etomidate administration, heart rate, arterial oxygen tension, and oxygen utilization ratio increased. Compared with baseline values, the following variables were decreased: mean arterial pressure, mean pulmonary arterial pressure, central venous pressure, pulmonary wedge pressure, cardiac index, oxygen delivery, mixed venous oxygen tension, mixed venous oxygen content, and arterial carbon dioxide tension. Three minutes after etomidate administration, central venous pressure, mixed venous and arterial carbon dioxide tension, and venous admixture increased, and heart rate, arterial and venous pH, and arterial oxygen tension decreased, compared with values measured immediately prior to etomidate administration. Fifteen minutes after etomidate injection, arterial pH and heart rate remained decreased. At 30 minutes, only heart rate was decreased, and at 60 minutes, mean arterial pressure was increased, compared with values measured before etomidate administration. Results of this study indicate that etomidate induces minimal changes in cardiopulmonary function when administered to hypovolemic dogs.

Perioperative smoking cessation and anesthesia: A review

Perioperative smoking causes acute changes in cardiopulmonary function that can have unfavorable implications for patients undergoing anesthesia. These cardiopulmonary effects are carbon monoxide and nicotine mediated changes in oxygen (O 2) delivery and myocardial OZ balance. Smokers also are at increased risk for postoperative pulmonary complications that are secondary to chronic changes in lung function. Smoking-induced acute changes in cardiopulmonary function can be largely avoided by a brief period of preoperative smoking abstinence. Bringing about a decrease in postoperative pulmonary complications requires a much longer period of preoperative abstinence. Because the perioperative period is in many ways an ideal time to abandon the smoking habit permanently, anesthesiologists, in cooperation with other health professionals, can perhaps play a more active role in facilitating this process.

Effects of allopurinol on smoke inhalation in the ovine model

We hypothesized that the pulmonary damage induced by smoke inhalation is the result of ischemic reperfusion injury. We determined the effect of allopurinol (xanthine oxidase inhibitor) on the pulmonary microvascular fluid flux in an ovine model after inhalation of cotton smoke (n = 13) and compared these data with those from untreated similarly smoke-injured (n = 7), as well as sham- (air, n = 9) smoked, animals and sheep given an equivalent dose of CO (n = 7). Smoke injury resulted in an increased lung lymph flow, lymph-to-plasma protein ratio, lung content of polymorphonuclear cells, and extravascular lung water (gravametric), in addition to histological evidence of tissue (pulmonary) edema and destruction. No significant difference was found in these variables between the sheep that were injured with smoke whether or not they were pretreated with allopurinol. The sham-smoked and CO-insufflated animals showed no significant changes in cardiopulmonary function or morphology. We conclude that there are few data to support a role of ischemic reperfusion injury in the pulmonary damage seen after smoke inhalation.

Impact of carbon monoxide on cardiopulmonary dysfunction after smoke inhalation injury.

With the inhalation of smoke, there are both cardiopulmonary changes and elevated levels of carbon monoxide (CO). We hypothesize that these changes in cardiopulmonary function are the result of a histotoxic hypoxia associated with CO poisoning. This hypothesis was tested in chronically instrumented sheep (n = 19). Piezoelectric crystals were attached to the left ventricle for the measurement of its external minor and major diameters in addition to wall thickness. A pressure transducer was placed in the left ventricle via the apex. The caudal-mediastinal lymph node was also cannulated. After a five-day recovery period, six sheep (smoke group) were insufflated with four series of 16 breaths (700 ml/breath) of cotton smoke, and five sheep (control group) were insufflated with air using a modified bee smoker (smoke group: COHb, 90 +/- 6%; control group: COHb, 6 +/- 1%). Eight sheep (CO group) were ventilated with 2% CO in air to reach a COHb of 90% (COHb, 92 +/- 1%). In the smoke group, lung lymph flow reached 42 +/- 10 ml/hr at 24 hours after smoke insufflation (baseline, 6 +/- 1 ml/hr). The maximum elastance of the left ventricle (end-systolic pressure-volume ratio), a sensitive index of myocardial contractility, was significantly decreased from a baseline of 6.5 +/- 0.9 to 3.3 +/- 0.7 mm Hg/ml. In the control and CO group, neither lung lymph flow nor maximum elastance varied from the baseline value. We conclude that the cardiopulmonary dysfunction after smoke inhalation does not occur after a similar exposure to CO. Initial CO poisoning alone is not a causative factor of cardiopulmonary dysfunction after smoke inhalation.

Cardiopulmonary Function Changes after Swimming Training in Subjects with Sequela of Poliomyelitis

Cardiopulmonary Function Changes after Swimming Training in Subjects with Sequela of Poliomyelitis

Cardiopulmonary effects of the volume recruitment manoeuvre in infant swine

The volume recruitment manoeuvre is a non-invasive technique used to measure respiratory mechanics in infants. Because airway pressure increases during this manoeuvre, lung volume, compliance and cardiac output may change. In order to assess possible changes in cardiopulmonary function caused by the volume recruitment manoeuvre, we applied this technique to seven intubated infant swine breathing spontaneously during anaesthesia with halothane and N2O. Tidal volume (VT), respiratory frequency, arterial blood gases, cardiac output (CO) and total respiratory compliance were measured before and after the manoeuvre. In three swine functional residual capacity (FRC) was measured by helium dilution before the manoeuvre, and in four swine diaphragmatic EMG was recorded continuously. Finally, all swine were paralysed during volume recruitment to assess the contribution of the respiratory muscles to post-manoeuvre respiratory mechanics. VT and f increased immediately after the manoeuvre but there were no significant changes in PaCO2, or alveolar to arterial oxygen gradient. There was a small but statistically significant decrease in CO. Compliance increased by 17.8 +/- 3.6 per cent and FRC increased by a mean of 41.1 ml (or 51.9 per cent increase above the baseline FRC). The increase in FRC could not be explained by active mechanisms since the diaphragmatic EMG showed no post-inspiratory activity and neuromuscular paralysis did not decrease FRC. We conclude that the volume recruitment manoeuvre increases FRC and compliance by recruiting collapsed alveoli, and this effect must be taken into consideration when applying this test to infants.

A new experimental approach for the study of cardiopulmonary physiology during early development.

In this report, an experimental approach and newly designed apparatus for liquid ventilation of preterm animals are described. Findings of age-related changes in cardiopulmonary function of this animal preparation are presented. Thirty-one lambs, 102-137 days gestation (term 147 +/- 3 days), were studied. The carotid artery, jugular vein, and trachea of the exteriorized fetus were cannulated under local anesthesia. Immediately after cesarean section delivery, ventilation commenced; warmed (39 degrees C) and oxygenated (PIO2 greater than 500 Torr) liquid fluorocarbon (RIMAR 101) was delivered to the lung by a mechanically assisted liquid ventilation system. Skeletal muscle paralysis, low-dose exogenous buffering, and thermal support were maintained during the 3-h experiment. Pulmonary gas exchange, acid-base status, and cardiopulmonary and metabolic function were assessed. By utilizing these techniques, effective arterial oxygenation, CO2 elimination, acid-base status, and cardiovascular stability were supported independent of gestational age. The results demonstrate a developmental increase in specific lung compliance and mean arterial pressure and decrease in heart rate and systemic O2 consumption per kilogram with advancing gestational age. These findings demonstrate that liquid ventilation negates the dependency of effective pulmonary gas exchange on surfactant development, thereby extending the limits of viability of the immature extrauterine lamb. As such this new experimental approach is useful for the study of physiological development over an age range previously limited to fetal animal preparations and, therefore, may provide insight regarding adaptation of the premature to the extrauterine environment.

下部食道噴門がんに対する根治手術 再建術式と術後機能

下部食道噴門がんに対する根治手術 再建術式と術後機能

Application of bromhexine metabolite VIII (NA 872) and bromhexine-glucose in treatment of adult respiratory distress syndrome; experimental and clinical results .

The authors study the changes in cardiopulmonary function after application of bromhexine metabolite VIII (NA 872) in an animal model of adult respiratory distress syndrome (ARDS) and bromhexine glucose solution (BGS) in ARDS patients. After damage of the lung alveolar surfactant by intratracheal atomization of 0.2 M HCl in LEWE Minipigs significant changes in lung compliance, dead space ventilation, venous admixture, alveolo-arterial oxygen tension difference, pulmonary vascular resistance, and oxygen uptake are present under application of NA 872 in comparison to untreated animals. In ARDS patients treated with BGS, pulmonary function is significantly ameliorated indicated by changes in static effective compliance, oxygen exchange ratio, and alveolo-arterial oxygen tension difference.

Response to blunt chest injury: a new experimental model.

MOSELEY, ROGER V. MAJOR MC; VERNICK, JEROME J. MAJOR MC; DOTY, DONALD B. MAJOR MC Author Information

Effects of epinephrine on asthmatic children: Effects of epinephrine on blood glucose, pulmonary function, and heart rate of children with asthma of varying severity

Hyperglycemic responses and changes in cardiopulmonary function following an injection of epinephrine were investigated in four groups of asthmatic children (a total of 61 subjects, 40 boys and 21 girls) 6 to 16 years of age. The groups were classified according to the severity of asthma and the medication needed to control it. Differences were observed in the responses of the four groups, the lowest hyperglycemic response being noted in the most severe cases. Corticosteroids or adrenergic drugs taken within 30 days prior to the study did not appear to influence the responses in any of the groups. The relative improvement in pulmonary function—namely, maximal midexpiratory flow—induced by epinephrine was almost identical in all groups, though the actual ventilatory impairment in absolute terms was much more marked among the children with severe chronic asthma, both before and after epinephrine. There was no uniform pulse acceleration following epinephrine nor was there any correlation between pulse rate and hyperglycemic responses. It is concluded that the magnitude of the hyperglycemic response to injected epinephrine is related to the severity of asthma and may be a useful indicator of the progress and prognosis of this condition.

Changes of Cardiopulmonary Function under Seasonal Influence among the Hospitalized Pneumoconiotic Patients

Changes of Cardiopulmonary Function under Seasonal Influence among the Hospitalized Pneumoconiotic Patients

STUDIES OF THE EFFECT OF INTERMITTENT POSITIVE PRESSURE BREATHING UPON THE CARDIOPULMONARY DYNAMICS

The cardio-pulmonary dynamics were studied in 8 cases of obstructive pulmonary emphysema, 2 cases of non-obstructive pulmonary emphysema and 3 cases of bronchial asthma before, during and after IPPB (intermittent positive pressure breathing) for 10 minutes using room air, and 2 cases of obstructive pulmonary emphysema before and 3 weeks after IPPB therapy and 2 cases of bronchial asthma before and 1 week after the same treatment. We also compared the changes in cardiopulmonary function by IPPB with those by inhalation of 100 percent oxygen. The alveolar hypoventilation was corrected by IPPB causing mechanical hyperventilation, with resultant improvement of ventilation-perfusion relationships. Thus hypoxemia and hypercapnia were corrected. As for the acid base balance, respiratory acidosis was markedly improved. As far as the hemodynamics are concerned, the cardiac output was increased, while the pulmonary arterial pressure and the pulmonary blood volume were decreased, which could be considered to show the therapeutic effect of IPPB on cor pulmonale. The same tendency was observed after treatment with IPPB for 1 or 3 weeks. A danger of respiratory acidosis could be avoided when inhalation of pure oxygen was done by means of IPPB. The conclusion is that IPPB is not a symptomatic treatment, but a therapeutic measure aiming to correct disturbed pulmonary function, and is at present the most effective treatment for chronic pulmonary insufficiency, for which there had not been good therapeutic means.