المؤلفون: Arnold Zidulka, David Lockhat, David Langleben

المصدر: The American review of respiratory disease. 146(3)

مصطلحات موضوعية: Pulmonary and Respiratory Medicine, Artificial ventilation, Cardiac output, Functional Residual Capacity, medicine.medical_treatment, Ventilators, Negative-Pressure, Positive pressure, Hemodynamics, Inferior vena cava, Positive-Pressure Respiration, Dogs, medicine, Tidal Volume, Animals, Lung volumes, Respiratory system, Monitoring, Physiologic, business.industry, respiratory tract diseases, medicine.vein, Evaluation Studies as Topic, Anesthesia, Breathing, Blood Gas Analysis, business

الوصف: In seven anesthetized dogs, ventilated with matching lung volumes, tidal volumes, and respiratory rates, we compared the effects on cardiac output (CO), arterial venous oxygen saturation difference (SaO2 - SVO2), and femoral and inferior vena cava pressure (1) intermittent positive pressure ventilation with positive end-expiratory pressure (CPPV); (2) iron-lung ventilation with negative end-expiratory pressure (ILV-NEEP); (3) grid and wrap ventilation with NEEP applied to the thorax and upper abdomen (GW-NEEP). The values of CO and SaO2 - SVO2 with ILV-NEEP were similar to those with CPPV. However, with GW-NEEP as compared with ILV-NEEP, mean CO was greater (2.9 versus 2.6 L/min, p = 0.02) and mean (SaO2 - SVO2) was lower (26.6% versus 28.3%, p = NS). Mean PFEM-IVC was higher with GW-NEEP than with the other types of ventilation. We conclude that (1) ILV-NEEP is hemodynamically equivalent to CPPV and (2) GW-NEEP has less adverse hemodynamic consequences. has less adverse hemodynamic consequences.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4c8eb2560c9f311d92b77b6e4f04fd9eTest
https://pubmed.ncbi.nlm.nih.gov/1519847Test

المؤلفون: D. Fitchett, M. Skaburskis, A. Zidulka, A. Rivero

المصدر: The American review of respiratory disease. 141(4 Pt 1)

مصطلحات موضوعية: Pulmonary and Respiratory Medicine, Artificial ventilation, Heart Failure, Cardiac output, Supine position, business.industry, medicine.medical_treatment, Ventilators, Negative-Pressure, Hemodynamics, Pulmonary Edema, medicine.disease, Pulmonary edema, Oxygen, Positive-Pressure Respiration, Dogs, Anesthesia, Heart failure, Breathing, medicine, Animals, Pulmonary wedge pressure, business, Tidal volume

الوصف: We have previously shown improved cardiac output (QT) with external continuous negative-pressure ventilation (CNPV) compared with continuous positive-pressure ventilation (CPPV) in dogs with low pressure pulmonary edema (1). The current study was done to determine if this effect was reversed in high pressure pulmonary edema. Seven supine, anesthetized dogs were fluid-loaded and treated with disopyramide (3.5 to 7.0 mg/kg) and propranolol (0.25 to 1.5 mg/kg). This produced a mean pulmonary wedge pressure (Ppaw) of 21.0 mm Hg on intermittent positive-pressure ventilation (IPPV). CPPV and CNPV were then alternated at 30-min intervals. Ventilators were matched for oxygen concentration, frequency, tidal volume (VT), and the increment in FRC (delta FRC) produced by a given positive (PEEP) or negative (NEEP) end-expiratory pressure. During 20 cm H2O of PEEP, QT values were significantly depressed from IPPV control values (2.13 +/- 0.2 versus 1.27 +/- 0.2 L/min, p less than 0.05) but not during CNPV with equivalent NEEP (1.66 +/- 0.2 L/min). Although arterial oxygen saturations were similar, mixed venous oxygen saturations were depressed by CPPV with PEEP of 15 and 20 cm H2O (67.9 +/- 3.8% during IPPV versus 54.1 +/- 4.9 and 51.9 +/- 5.8%, respectively, p less than 0.05 in both instances) but not during equivalent CNPV (59.9 +/- 4.3 and 58.7 +/- 4.5%). Despite potentially increased left ventricular afterload, external negative chest wall ventilation with NEEP does not appear to significantly depress QT compared with CPPV even when Ppaw is high and myocardial contractility is impaired.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::434923dc78abd6a0a19b369e2b015eb4Test
https://pubmed.ncbi.nlm.nih.gov/2183657Test

المؤلفون: Gerard J. Criner, John Rassulo, Mary Gilmartin, Mary Bermudez, Gary Miller, Bartolome R. Celli, Howard Lee, Barry J. Make

المصدر: The American review of respiratory disease. 140(5)

مصطلحات موضوعية: Pulmonary and Respiratory Medicine, Artificial ventilation, Male, medicine.medical_specialty, Time Factors, medicine.medical_treatment, Ventilators, Negative-Pressure, Vital Capacity, Airflow obstruction, law.invention, Randomized controlled trial, law, Forced Expiratory Volume, medicine, Humans, Pulmonary rehabilitation, Theophylline, Prospective Studies, Clinical Trials as Topic, business.industry, Respiration, Respiratory disease, medicine.disease, Surgery, Airway Obstruction, Negative pressure ventilation, Respiratory failure, Anesthesia, Chronic Disease, Female, business, medicine.drug, Follow-Up Studies

الوصف: The effect of intermittent external negative pressure ventilation (ENPV) with the Emerson Pulmowrap ventilator upon leg cycle endurance time (ET), maximal transdiaphragmatic pressure (Pdimax), breathing pattern as expressed by the tension time index (TTdi), and sense of well being was studied in 16 patients with severe chronic airflow obstruction (CAO). The patients were randomized to 3 wk of in-hospital pulmonary rehabilitation (Group I, seven patients) or the same program plus ENPV (Group II, nine patients). Both groups were similar in terms of age (65 +/- 8 versus 61 +/- 13 yr), severity of CAO (FEV1 of 0.64 +/- 0.14 versus 0.59 +/- 0.18 L), and PaCO2 (44 +/- 9 versus 45 +/- 7 mm Hg). Blood theophylline levels and nutritional status were also similar in both groups. Baseline ET (2.9 +/- 0.6 versus 3.8 +/- 1.6 min) and Pdimax (45 +/- 15 versus 56 +/- 18 cm H2O) were decreased in both groups. Baseline TTdi was high but similar in both groups; at rest the values were 0.15 +/- 0.05 versus 0.16 +/- 0.04, and at end-exercise they were 0.17 +/- 0.06 versus 0.21 +/- 0.12. After treatment FEV1 and Pdimax remained unchanged, but the patients in both groups manifested clinical improvement and had a significant increase in mean ET (Group I from 2.9 to 6.9 and Group II from 3.8 to 6 min, p less than 0.01). TTdi decreased both at rest (0.14 +/- 0.07 versus 0.13 +/- 0.04) and at end-exercise (0.14 +/- 0.06 versus 0.15 +/- 0.09) with no difference between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::813def56c65eb7bf741aef56a4a6689aTest
https://pubmed.ncbi.nlm.nih.gov/2683904Test