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Stawicki SP, Goyal M, Sarani B. High-frequency oscillatory ventilation (HFOV) and airway pressure release ventilation (APRV): a practical guide. J Intensive Care Med 2009; 24:215-29. [PMID: 19617228 DOI: 10.1177/0885066609335728] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Despite advances in ventilator management, 31% to 38% of patients with adult respiratory distress syndrome (ARDS) will die, some from progressive respiratory failure. Inability to adequately oxygenate patients with severe ARDS has prompted extensive efforts to identify what are now known as alternative modes of ventilation including high-frequency oscillatory ventilation and airway pressure release ventilation. Both modalities are based on the principles of the open-lung concept and aim to improve oxygenation by keeping the lung uniformly inflated for an extended period of time. Although a mortality benefit has not been proven, some patients may benefit from these alternative modes of ventilation as rescue measures while the underlying process resolves. The purpose of this article is to review the evidence and mechanisms underlying each modality and to describe the fundamental steps in initiating, adjusting, and terminating these modes of ventilation.
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Affiliation(s)
- S P Stawicki
- Division of Traumatology and Surgical Critical Care, Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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2
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Putensen C, Muders T, Varelmann D, Wrigge H. The impact of spontaneous breathing during mechanical ventilation. Curr Opin Crit Care 2006; 12:13-8. [PMID: 16394778 DOI: 10.1097/01.ccx.0000198994.37319.60] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW In patients with acute respiratory distress syndrome, controlled mechanical ventilation is generally used in the initial phase to ensure adequate alveolar ventilation, arterial oxygenation, and to reduce work of breathing without causing further damage to the lungs. Although introduced as weaning techniques, partial ventilator support modes have become standard techniques for primary mechanical ventilator support. This review evaluates the physiological and clinical effects of persisting spontaneous breathing during ventilator support in patients with acute respiratory distress syndrome. RECENT FINDINGS The improvements in pulmonary gas exchange, systemic blood flow and oxygen supply to the tissue which have been observed when spontaneous breathing has been maintained during mechanical ventilation are reflected in the clinical improvement in the patient's condition. Computer tomography observations demonstrated that spontaneous breathing improves gas exchange by redistribution of ventilation and end-expiratory gas to dependent, juxtadiaphragmatic lung regions and thereby promotes alveolar recruitment. Thus, spontaneous breathing during ventilator support counters the undesirable cyclic alveolar collapse in dependent lung regions. In addition, spontaneous breathing during ventilator support may prevent increase in sedation beyond a level of comfort to adapt the patient to mechanical ventilation which decreases duration of mechanical ventilator support, length of stay in the intensive care unit, and overall costs of care giving. SUMMARY In view of the recently available data, it can be concluded that maintained spontaneous breathing during mechanical ventilation should not be suppressed even in patients with severe pulmonary functional disorders.
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Affiliation(s)
- Christian Putensen
- Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany.
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3
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Putensen C, Hering R, Muders T, Wrigge H. Assisted breathing is better in acute respiratory failure. Curr Opin Crit Care 2005; 11:63-8. [PMID: 15659947 DOI: 10.1097/00075198-200502000-00010] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
PURPOSE OF REVIEW Mechanical ventilation is usually provided in acute lung injury to ensure alveolar ventilation and reduce the patients' work of breathing without further damaging the lungs by the treatment itself. Although partial ventilatory support modalities were initially developed for weaning from mechanical ventilation, they are increasingly used as primary modes of ventilation, even in patients in the acute phase of pulmonary dysfunction. The aim of this paper is to review the role of spontaneous breathing ventilatory modalities with respect to their physiologic or clinical evidence. RECENT FINDINGS By allowing patients with acute lung injury to breathe spontaneously, one can expect improvement in gas exchange and in systemic blood flow, on the basis of both experimental and clinical trials. In addition, by increasing end-expiratory lung volume, as will occur when airway pressure release ventilation is used, recruitment of collapsed or consolidated lung is likely to occur, especially in juxtadiaphragmatic lung regions. Until recently, traditional approaches to mechanical ventilatory support of patients with acute lung injury have called for adaptation of the patient to the mechanical ventilator using heavy sedation and administration of neuromuscular blocking agents. Recent investigations have questioned the utility of sedation, muscle paralysis, and mechanical control of ventilation. Further, evidence exists that lowering sedation levels will decrease the duration of mechanical ventilatory support, the length of stay in the intensive care unit, and the overall costs of hospitalization. SUMMARY On the basis of currently available data, the authors suggest the use of techniques of mechanical ventilatory support that maintain, rather than suppress, spontaneous ventilatory effort, especially in patients with severe pulmonary dysfunction.
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Affiliation(s)
- Christian Putensen
- Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany.
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4
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Putensen C, Wrigge H. Clinical review: biphasic positive airway pressure and airway pressure release ventilation. Crit Care 2004; 8:492-7. [PMID: 15566621 PMCID: PMC1065046 DOI: 10.1186/cc2919] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
This review focuses on mechanical ventilation strategies that allow unsupported spontaneous breathing activity in any phase of the ventilatory cycle. By allowing patients with the acute respiratory distress syndrome to breathe spontaneously, one can expect improvements in gas exchange and systemic blood flow, based on findings from both experimental and clinical trials. In addition, by increasing end-expiratory lung volume, as occurs when using biphasic positive airway pressure or airway pressure release ventilation, recruitment of collapsed or consolidated lung is likely to occur, especially in juxtadiaphragmatic lung legions. Traditional approaches to mechanical ventilatory support of patients with acute respiratory distress syndrome require adaptation of the patient to the mechanical ventilator using heavy sedation and even muscle relaxation. Recent investigations have questioned the utility of sedation, muscle paralysis and mechanical control of ventilation. Furthermore, evidence exists that lowering sedation levels will decrease the duration of mechanical ventilatory support, length of stay in the intensive care unit, and overall costs of hospitalization. Based on currently available data, we suggest considering the use of techniques of mechanical ventilatory support that maintain, rather than suppress, spontaneous ventilatory effort, especially in patients with severe pulmonary dysfunction.
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Affiliation(s)
- Christian Putensen
- Department of Anaesthesiology and Intensive Care Medicine, University of Bonn, Bonn, Germany.
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5
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Videtta W, Villarejo F, Cohen M, Domeniconi G, Santa Cruz R, Pinillos O, Rios F, Maskin B. Effects of positive end-expiratory pressure on intracranial pressure and cerebral perfusion pressure. ACTA NEUROCHIRURGICA. SUPPLEMENT 2003; 81:93-7. [PMID: 12168368 DOI: 10.1007/978-3-7091-6738-0_25] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The effect of positive end-expiratory pressure (PEEP) on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) has been reported by several investigators, without any consensus being reached. Acute neurological and neurosurgical patients suffer intracranial hypertension and acute lung injury with hypoxemia. Since PEEP may improve hypoxemia but elevate ICP and decrease CPP, it is important to determine the influence of varying levels of PEEP on ICP and CPP. The aim of the study was to investigate the changes in ICP and CPP associated with different levels of PEEP. Twenty patients requiring ICP monitoring and mechanical ventilation were enrolled. Patients had severe head injury (n = 10), spontaneous intracerebral haemorrhage (n = 5), and subarachnoid haemorrhage (n = 5). PEEP was raised from 5 (basal) to 15 cm H2O in steps of 5 cm H2O. After at least 10 minutes of each new PEEP setting, ICP and CPP were measured. PEEP at 10 and 15 cm H2O produced a significant (p < 0.05) increase in intracranial pressure 11.6 +/- 5.6 and 14.6 +/- 6.28 mm Hg, respectively; no significant (p = 0.819) change occurred in CPP.
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Affiliation(s)
- W Videtta
- ICU, Hospital Nacional Prof. A. Posadas, University of Buenos Aires, Haedo, Argentina
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6
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Abstract
On the basis of currently available data, it can be suggested that maintained spontaneous breathing during mechanical ventilation should not be suppressed even in patients with severe pulmonary dysfunction if no contraindications, such as increased intracranial pressure, are present. Improvements in pulmonary gas exchange, systemic blood flow, and oxygen supply to tissues, which have been observed when spontaneous breathing was allowed during ventilatory support, are reflected in the clinical improvement in the patient's condition, as indicated by significantly fewer days with ventilation, earlier extubation, and shorter stays in the intensive care unit. The positive effects of spontaneous breathing have been documented only for some of the available partial ventilatory support modalities. If ventilatory modalities are limited to those whose positive effects have been documented, then partial ventilatory support can be used as a primary modality even in patients with severe pulmonary dysfunction. Whereas controlled mechanical ventilation followed by weaning with partial ventilatory support modalities has been the earlier standard in ventilation therapy, this approach should be reconsidered in view of the available data.
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Affiliation(s)
- Christian Putensen
- Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany.
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8
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Hartmann M, Rosberg B, Jönsson K. The influence of different levels of PEEP on peripheral tissue perfusion measured by subcutaneous and transcutaneous oxygen tension. Intensive Care Med 1992; 18:474-8. [PMID: 1289372 DOI: 10.1007/bf01708584] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To compare subcutaneous (PscO2) and transcutaneous (PtcO2) oxygen tension measurements in relation to hemodynamic variables at different levels of PEEP, and to evaluate the usefulness of these measurements as monitors of peripheral tissue perfusion. DESIGN Prospective trial. SETTING Intensive care unit in a university hospital. PATIENTS Seven patients with gastric cancer who where undergoing total gastrectomy. INTERVENTIONS Silicone catheter was placed in the upper arm and transcutaneous oxygen monitor was placed on the upper part of the chest. A pulmonary artery catheter was placed in the right pulmonary artery. MEASUREMENTS AND RESULTS PscO2 and PtcO2 together with hemodynamic variables were measured at different levels of PEEP. Progressive increase of PEEP reduced cardiac index (CI) (p < 0.05) with a concomitant decrease of PscO2 (p < 0.05) and oxygen delivery (DO2) (p < 0.05). Changes in PtcO2 paralleled changes in arterial oxygen tension (PaO2), but no correlation was found between PtcO2, CI and DO2. CONCLUSION PscO2 is a sensitive indicator of subcutaneous tissue perfusion, which can be used to identify the PEEP level, with optimum peripheral perfusion. PscO2 seems to be a more reliable indicator of tissue perfusion than PtcO2.
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MESH Headings
- Aged
- Aged, 80 and over
- Blood Gas Analysis/standards
- Blood Gas Monitoring, Transcutaneous/instrumentation
- Blood Gas Monitoring, Transcutaneous/methods
- Blood Gas Monitoring, Transcutaneous/standards
- Cardiac Output
- Catheterization, Swan-Ganz
- Evaluation Studies as Topic
- Gastrectomy
- Humans
- Intensive Care Units
- Middle Aged
- Monitoring, Physiologic/instrumentation
- Monitoring, Physiologic/methods
- Monitoring, Physiologic/standards
- Oxygen/blood
- Oxygen/pharmacokinetics
- Oxygen Consumption
- Polarography/instrumentation
- Polarography/methods
- Polarography/standards
- Positive-Pressure Respiration/methods
- Positive-Pressure Respiration/standards
- Prospective Studies
- Sensitivity and Specificity
- Stomach Neoplasms/surgery
- Tissue Distribution
- Tonometry, Ocular/instrumentation
- Tonometry, Ocular/methods
- Tonometry, Ocular/standards
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Affiliation(s)
- M Hartmann
- Department of Anaesthesiology, Malmö General Hospital, University of Lund, Sweden
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9
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Nishimura M, Takezawa J, Imanaka H, Taenaka N, Yoshiya I. Jet flow-regulated expiratory resistance to maintain constant CPAP during the entire respiratory phase. Chest 1989; 95:876-80. [PMID: 2647423 DOI: 10.1378/chest.95.4.876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We have developed a new continuous positive airway pressure (CPAP) device that consists of a microcomputer, a pressure transducer, and a pair of electronic interface valves. One of these valves creates the inspiratory demand flow, and the other creates the opposing jet flow by acting as an expiratory valve to maintain a constant CPAP. By controlling the two electronic interface valves, the airway pressure can be kept constant during the entire respiratory cycle. We compared our device with CPAP systems supplied with commercially available ventilators: the Puritan-Bennett 7200a, the Bear 5, the Servo 900C, and the CV 2000. A two-chambered spring loaded model lung was used to simulate inspiration and a piston pump model lung to simulate active exhalation. We compared both the inspiratory triggering work (WWIt) and expiratory flow-resistive work (WE) of each ventilator while in CPAP mode by calculating the corresponding areas of the pressure-volume loops using electrical integration. The WWIt of our apparatus and demand-flow ventilators was much smaller than that of the CV 2000. In our device, WE was also much smaller than those of the others. These results indicate that our device can be used for CPAP without causing airway pressure fluctuation, and therefore, without imposing an extra workload on the patient.
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Affiliation(s)
- M Nishimura
- Intensive Care Unit, Osaka University Hospital, Japan
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10
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Perkins MW, Dasta JF, DeHaven B. Physiologic implications of mechanical ventilation on pharmacokinetics. DICP : THE ANNALS OF PHARMACOTHERAPY 1989; 23:316-23. [PMID: 2658376 DOI: 10.1177/106002808902300408] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Numerous factors present in the critically ill patient decrease drug clearance. The contribution of one factor, mechanical ventilation, to this decrease is largely unknown and unquantified. This article attempts to review the physiologic effects of mechanical ventilation and to propose theoretical changes in the pharmacokinetics of concomitantly administered drugs. Mechanical ventilation with or without positive end-expiratory pressure is a well-documented cause of decreases in cardiac output, hepatic and renal blood flow, glomerular filtration rate, and urine flow. The mean airway pressure delivered, the pathophysiologic state of the patient, and coexisting therapeutic interventions affect the degree of hemodynamic alteration. Theoretically, these hemodynamic changes can decrease the clearance of several drugs frequently administered to critically ill patients. Decreased hepatic blood flow decreases the clearance of nonrestrictively cleared drugs. The pharmacokinetics of drugs predominantly renally cleared, by either glomerular filtration or tubular secretion, are affected by a decrease in renal blood flow or glomerular filtration rate. Also, the clearance of agents for which tubular reabsorption is important may decrease because the reduction in urine flow resulting from mechanical ventilation allows increased time for drug reabsorption. Interventions that minimize the decrease in cardiac output and organ blood flow and, theoretically, the risk of the adverse drug reactions from decreased drug clearance include expansion of intravascular volume, administering positive inotropic agents, and decreasing mean airway pressure. Monitoring serum concentration of critical and toxic agents suspected to have altered clearance in patients receiving mechanical ventilation is recommended. We hope that our article will stimulate future research in this area to give clinicians guidelines for drug dosing in patients receiving mechanical ventilation.
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Affiliation(s)
- M W Perkins
- College of Pharmacy, Ohio State University, Columbus 43210
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11
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Abstract
Adult respiratory distress syndrome, a clinical syndrome of respiratory failure that follows many kinds of insults, often in patients with no previous pulmonary disease, occurs in pediatric patients. This group of disorders has a typical clinical, pathologic, and pathophysiologic course, the hallmark of which is injury to the alveolar-capillary membrane with increased permeability of the pulmonary vasculature and pulmonary edema. Resolution may occur at any stage, but most patients die and many develop chronic lung disease requiring respiratory support for weeks or months. Multiple organ system failure, secondary infection, and irreversible respiratory dysfunction are responsible for the poor outcome. The underlying mechanisms that relate injury to the development of pulmonary disease are unclear. In some cases there may be direct injury to the lung, but in others, such as septic shock, there are mediators that link the initial insult to the subsequent lung injury. The leukocyte may have a central role in this process, although this is uncertain. Therapeutic measures needed to support the patient, especially increased inspired oxygen, are additional factors in the progression of lung disease. Current therapy, as summarized in Table II, is primarily supportive. Efforts to treat ARDS after it is clinically apparent have been disappointing. The pathogenic mechanisms that lead to ARDS are probably well advanced by the time the syndrome is diagnosed on the basis of the usual clinical signs. Therefore an emphasis on understanding the mechanisms of lung injury so that specific markers can be used to predict which patients will develop ARDS, allowing intervention in the early stages of the process, may prove rewarding.
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Affiliation(s)
- J Royall
- Pediatric Intensive Care Unit, Children's Medical Center, University of Texas Health Science Center of Dallas
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12
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Haake R, Schlichtig R, Ulstad DR, Henschen RR. Barotrauma. Pathophysiology, risk factors, and prevention. Chest 1987; 91:608-13. [PMID: 3549176 DOI: 10.1378/chest.91.4.608] [Citation(s) in RCA: 142] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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13
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Woodcock GB, Nickles GB, Savage MG, Kramer HS. Adult respiratory distress syndrome as a complication of oral and maxillofacial surgery. J Oral Maxillofac Surg 1985; 43:782-5. [PMID: 3862776 DOI: 10.1016/0278-2391(85)90334-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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14
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Fauss BG, Rah KH. Continuous mixed venous oxygen saturation monitoring for perioperative management of a boy undergoing a modified Fontan procedure. J Clin Monit Comput 1985; 1:52-7. [PMID: 4093788 DOI: 10.1007/bf02832687] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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15
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Steinhoff HH, Kohlhoff RJ, Falke KJ. Facilitation of renal function by intermittent mandatory ventilation. Intensive Care Med 1984; 10:59-65. [PMID: 6425381 DOI: 10.1007/bf00297559] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The effects of intermittent mandatory ventilation (IMV) and controlled mechanical ventilation (CMV) on excretory function and the hemodynamics of the kidneys were studied in two groups of anaesthetized dogs during periods of 3 and 4 h. IMV was associated with statistically significant improved urinary output and renal plasma flow of approximately 50 and 35%, respectively. Graphical and statistical analysis revealed certain cross-over effects indicating that the beneficial effect of IMV was more pronounced if it was used following CMV. The improvements in renal function were interpreted as consequences of decreased mean intrathoracic pressures during IMV as compared to CMV. A correlation to global hemodynamic changes could not be established. IMV does facilitate kidney function and hence may successfully counteract the retention of water and salt which occurs during prolonged mechanical ventilation.
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Snyder JV, Carroll GC, Schuster DP, Culpepper J, Klain M. Mechanical ventilation: physiology and application. Curr Probl Surg 1984; 21:1-87. [PMID: 6368135 DOI: 10.1016/0011-3840(84)90002-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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18
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Abstract
Acute respiratory failure is frequently fatal. Attempts to decrease mortality must include attention to pulmonary and extrapulmonary complications. Pulmonary complications include pulmonary emboli, barotrauma, fibrosis, and pneumonia. Swan-Ganz catheters, tracheal intubation, and mechanical ventilation can also result in pulmonary complications. Extra-pulmonary complications such as gastrointestinal hemorrhage, renal failure, infection, and thrombocytopenia may increase mortality. Early diagnosis, aggressive treatment, and prophylaxis of complications should increase survival.
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Abstract
The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs.
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MESH Headings
- Adult
- History, 16th Century
- History, 17th Century
- History, 18th Century
- History, 19th Century
- History, 20th Century
- Humans
- Infant, Newborn
- Positive-Pressure Respiration
- Respiration, Artificial/history
- Respiration, Artificial/trends
- Safety
- Ventilators, Mechanical/history
- Ventilators, Mechanical/trends
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20
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Prakash O, Meij S, Van Der Borden B. Spontaneous ventilation test vs intermittent mandatory ventilation. An approach to weaning after coronary bypass surgery. Chest 1982; 81:403-6. [PMID: 6978235 DOI: 10.1378/chest.81.4.403] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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21
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Steinhoff H, Falke K, Schwarzhoff W. Enhanced renal function associated with intermittent mandatory ventilation in acute respiratory failure. Intensive Care Med 1982; 8:69-74. [PMID: 7076977 DOI: 10.1007/bf01694869] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In ten patients suffering from acute respiratory failure (ARF) renal function was evaluated during 2-h periods of intermittent mandatory ventilation (IMV) or controlled mechanical ventilation (CMV). Urine flow, osmolal and creatinine clearances were significantly lower during CMV in comparison to both IMV phases and the free water clearance was less negative. Potassium excretion declined with CMV but remained reduced during the second IMV phase. There was no change in sodium excretion. This study suggests that in order to maintain renal function and prevent water retention the use of IMV should be considered whenever a sufficient mechanical reserve for partial spontaneous ventilation is present.
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22
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Simonneau G, Lemaire F, Harf A, Carlet J, Teisseire B. A comparative study of the cardiorespiratory effects of continuous positive airway pressure breathing and continuous positive pressure ventilation in acute respiratory failure. Intensive Care Med 1982; 8:61-7. [PMID: 7042791 DOI: 10.1007/bf01694868] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Positive end expiratory pressure (PEEP) produces cardiopulmonary effects whether administered by controlled positive pressure ventilation (CPPV) or continuous positive airway pressure (CPAP). In eight patients with acute respiratory failure, the effects of 20 cm PEEP administered via CPPV and CPAP were compared. An esophageal balloon was used to calculate the transmural vascular pressures. The control values under mechanical ventilation with no PEEP (IPPV) for PaO2 and QS/QT (FiO2 being 1.0) were respectively 132 +/- 15 mmHg and 31 +/- 3%; CPPV gave a PaO2 of 369 +/- 27 mmHg and QS/QT fo 14 +/- 1.6%, CPAP 365 +/- 18 mmHg and 18 +/- 1.3% respectively. The two different modes of ventilation (CPPV and CPAP) gave identical blood gas improvement through the same level of end expiratory transpulmonary pressure despite marked differences between absolute mean airway and esophageal pressures. Conversely, hemodynamic tolerance was very different from one technique to the other: CPPV depressed cardiac index from 3.4 +/- 0.3 to 2.4 +/- 0.2 1/min/m2 as well as decreasing transmural filling pressures, suggesting a reduction in venous return. Conversely, filling pressures maintained at control values during CPAP and cardiac indexes were unchanged.
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24
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25
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Rosegger H, Trittenwein G, Metzler H, Tscheliessnig KH, Hermann W. Influence of lipid infusion (0.4 g/kg/hr) and positive end expiratory pressure (8 cm H2O) on pulmonary function and hemodynamics in healthy anesthetized pigs. JPEN J Parenter Enteral Nutr 1981; 5:410-3. [PMID: 7031289 DOI: 10.1177/0148607181005005410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Fat emulsions are used increasingly for parenteral nutrition in premature infants suffering from various disorders, including respiratory insufficiency necessitating artificial ventilation with positive end expiratory pressure (PEEP). Both PEEP and lipid infusions (LI) may alter pulmonary hemodynamics. The simultaneous effect of LI and PEEP were therefore investigated. Five adult anesthetized Göttinger minipigs were infused with a 20% LI at a high rate of 0.4 g/kg/hr for 30 min, followed by PEEP of 8 cm H2O for 15 min. Catheters were inserted into the upper vena cava, the pulmonary artery, the right and left atrium, and the aorta, and pressures recorded continuously. Ventilation volume, respiratory fractional gas concentrations of O2 and CO2 (mass spectrometer), and blood gases were measured. The following parameters were calculated: total peripheral resistance, pulmonary arteriolar resistance, right-to-left shunt (QS/QT) dead space ventilation (VD/VT) and effective compliance. Total peripheral resistance remained unchanged. Pulmonary arteriolar resistance increased significantly during PEEP, PEEP + LI, but not during LI alone. QS/QT increased significantly during LI and returned to normal when PEEP was applied. VD/VT and effective compliance did not change during LI. The increased right to left shunt, caused by LI, is reduced by means of PEEP, while the pulmonary arteriolar resistance increased with PEEP and LI.
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26
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Klose R, Osswald PM. Effects of PEEP on pulmonary mechanics and oxygen transport in the late stages of acute pulmonary failure. Intensive Care Med 1981; 7:165-70. [PMID: 7021631 DOI: 10.1007/bf01724836] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In 23 patients with advanced stages of acute respiratory failure, the value of various parameters for estimating the efficiency of ventilation with PEEP were analysed. PEEP increments of 1 cm of water corresponded to an increase of PaO2 of 2 mmHg. The cardiac output decreased from 8.3 +/- 0.3 l/min mean value at ZEEP to 7.3 +/- 0.3 L/min at a PEEP of +15 cm H2O. Corresponding to this, the oxygen transport showed a decrease from 1042 +/- 62 ml/min to 894 +/- 115 ml/min. The total compliance of 34 ml/cm H2O at ZEEP is already significantly reduced (a sign of the severe respiratory failure) and falls still further at a PEEP of 15 cm H2O to 22 ml/cm H2O. No notable recruitment of non ventilated alveolar spaces can be expected, in spite of the slight increase in the arterial oxygen tension. Taking the "best PEEP" (PEEP with maximum oxygen transport) as a reference point, arterial and mixed venous oxygen tension increase, the cardiac output decreases above this point and the total respiratory compliance shows no obvious changes. In the advanced stage of severe respiratory failure one cannot use the mixed venous oxygen tension or the compliance to find the best PEEP. The danger of barotrauma by PEEP ventilation in cases of significantly reduced compliance has to be considered in the choice of the ventilation pattern. The arterial oxygen tension may lead to a wrong estimation of the total efficiency of PEEP.
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27
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PEEP and left ventricular performance. N Engl J Med 1981; 304:1428-9. [PMID: 7015128 DOI: 10.1056/nejm198106043042317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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28
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Good JT, Wolz JF, Anderson JT, Dreisin RB, Petty TL. The routine use of positive end-expiratory pressure after open heart surgery. Chest 1979; 76:397-400. [PMID: 383417 DOI: 10.1378/chest.76.4.397] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Because atelectasis of the left lower lobe is a frequent complication of open heart surgery, we evaluated the efficacy of routine therapy with positive end-expiratory pressure (PEEP) to prevent this complication. Twenty-four patients were randomly assigned to either a group receiving therapy with PEEP (ten patients) or to a group with no PEEP (14 patients). The two groups could not be distinguished by age, weight, the forced expiratory volume in one second (FEV1), the ratio of FEV1 over the forced vital capacity, the time on the pump, the units of blood transfused, the tidal volume, or the hours of mechanical ventilation. There was no significant roentgenographic difference between the two groups in either the degree or frequency of left lower lobe atelectasis. While the arterial-alveolar ratios tended to improve over time in those patients receiving therapy with PEEP, this improvement was not clinically significant. No complications were encountered with the use of PEEP. We conclude that the routine use of PEEP following open heart surgery is safe but offers no advantage over standard ventilatory techniques.
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Venus B, Jacobs HK, Lim L. Treatment of the adult respiratory distress syndrome with continuous positive airway pressure. Chest 1979; 76:257-61. [PMID: 380940 DOI: 10.1378/chest.76.3.257] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Fifteen patients in the early stages of the adult respiratory distress syndrome with severe hypoxemia who were capable of maintaining adequate spontaneous ventilation were treated with continuous positive airway pressure (CPAP). The optimal level of CPAP was adjusted for each patient to achieve the highest oxygenation with the least adverse hemodynamic effects. The optimal intravascular volume, judged by pulmonary arterial occlusion pressure, was maintained by infusion of lactated Ringer's solution. Application of an optimal CPAP ranging between 10 and 25 cm H2O significantly reduced the intrapulmonary shunt, increased the forced vital capacity, and decreased the respiration rate. The improvement in pulmonary status was achieved with no significant changes in cardiac output or the arterial-mixed venous oxygen content difference. Early application of an adjusted level of positive end-expiratory pressure using CPAP in patients with adequate levels of fluid is an effective and safe method of treating selected groups of patients in the early stages of the adult respiratory distress syndrome.
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Rao PS, Marino BL, Robertson AF. Usefulness of continuous positive airway pressure in differential diagnosis of cardiac from pulmonary cyanosis in newborn infants. Arch Dis Child 1978; 53:456-60. [PMID: 356748 PMCID: PMC1544947 DOI: 10.1136/adc.53.6.456] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Differential diagnosis of cyanosis in the neonate is difficult and cardiac catheterisation may be required for a correct diagnosis. It has been suggested that the response of PaO2 to continuous positive airway pressure (CPAP) with 100% oxygen may be useful. The purpose of this study was to test further this hypothesis by studying all neonates investigated for cyanosis with a PaO2 less than or equal to 50 torr in 0-8 to 1-0 F1O2. Arterial blood samples were obtained in an F1O2 of 0-21-0-4 and 0-8-1-0, and in an F1O2 of 0-8-1-0 with 8-10 cm CPAP, and were analysed for PaO2, PaCO2, and pH, bicarbonate being calculated. The final diagnoses were congenital heart disease (CHD) 21 cases, pulmonary parenchymal disease (PD) 10 cases, and persistent fetal circulation (PFC) 3 cases. No significant difference in pH, bicarbonate, or PaCO2 was observed among the three groups or with CPAP. In the CHD and PFC infants CPAP produced no significant change in PaO2. In the PD babies PaO2 increased by an average of 33 torr (P less than 0-05). Despite thus attaining statistical significance 2 PD infants had no increase in PaO2 with CPAP. An increase of PaO2 greater than 10 torr with CPAP suggests PD, and a nonsignificant increase in PaO2 does not rule out PD. Irrespective of initial PaO2, final PaO2 in 0-8-1-0 F1O2 with CPAP greater than 50 torr suggests PD, and less than 50 torr suggests CHD. The results indicate that CPAP may be used as an adjunct in differentiating cardiac from pulmonary disease.
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Sladen RN, Jenkins LC. Intermittent mandatory ventilation and controlled mechanical ventrilation without positive end-expiratory pressure following cardio-pulmonary bypass. CANADIAN ANAESTHETISTS' SOCIETY JOURNAL 1978; 25:166-72. [PMID: 656988 DOI: 10.1007/bf03004875] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In a group of 18 male patients undergoing coronary artery bypass grafting with cardiopulmonary bypass, the overall incidence of post-operative atelectasis was 60%. Nearly three-quarters occurred during anaesthesia. After operation there was no difference whether CMV or IMV without PEEP was provided overnight. Atelectasis already present did not improve and further atelectasis occurred. A role for IMV is not excluded, since it facilitates the use of PEEP. Many factors operate and interact to provoke atelectasis during anaesthesia, which increases post-operative morbidity. Many of these factors are prevertible or reversible if their physiological basis is understood. Optimal post-operative ventilation should be tailored to the needs of the individual patient and demands close co-operation between anaesthetist and surgeon.
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Liu CT, DeLauter RD, Griffin MJ, Hadick CL. Effects of staphylococcal enterotoxin B on functional and biochemical changes of the lung in rhesus monkeys. Toxicon 1978; 16:543-50. [PMID: 103247 DOI: 10.1016/0041-0101(78)90181-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Gilston A. The effects of PEEP on arterial oxygenation. An examination of some possible mechanisms. Intensive Care Med 1977; 3:267-71. [PMID: 338659 DOI: 10.1007/bf01641118] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The effect of positive and expiratory pressure (PEEP) on arterial oxygenation depends on many factors. Two of the most important are the "quality" and the "quantity" of the physiological shunt. The "quality" depends on the mixed venous oxygen tension, and the "quantity" on the shunt fraction. Each of these factors may rise or fall with PEEP, depending on the pulmonary and circulatory state of the patient. Their ultimate balance influences the change in arterial oxygen tension.
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Sjöstrand U. Summary of experimental and clinical features of high-frequency positive-pressure ventilation--HEPPV. ACTA ANAESTHESIOLOGICA SCANDINAVICA. SUPPLEMENTUM 1977; 64:165-78. [PMID: 339652 DOI: 10.1111/j.1399-6576.1977.tb01269.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Borg U, Lyttkens L, Nilsson LG, Sjöstrand U. Physiologic evaluation of the HFPPV pneumatic valve principle and PEEP. An experimental study. Acta Anaesthesiol Scand 1977; 64:37-53. [PMID: 22976 DOI: 10.1111/j.1399-6576.1977.tb01261.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In experiments in dogs the ventilatory and circulatory conditions prevailing with the ventilatory pattern in high-frequency positive-pressure ventilation (HFPPV) were investigated with use of a pneumatic valve principle and a ventilator system of an "open" character. Keeping the gas input constant the importance of insufflation frequency and insufflation time and the reactions to various levels of positive end-expiratory pressure (PEEP) were investigated in terms of changes in arterial pH, Pco2 and Po2. With the volumes of delivered gas kept constant, an increasing insufflation frequency from 60 to 100 per min gave a parallel decrease in tidal volume accompanied by lower maximum intratracheal pressures and a significant decrease in alveolar ventilation. Also taking into account the possibilities of inducing a suppression of the spontaneous respiration, higher ventilatory frequencies than 60 per min do now seem to introduce any further advantages. Including the associated effects on cardiac output and venous admixture, the cardio-pulmonary and circulatory parameters studied did not show any substantial changes with PEEP levels below 7.5--10 cm H2O. Thus the level of PEEP, which often is part of the ventilatory pattern in HFPPV, does not seem to have any untoward influence on the circulation (stroke volume, cardiac output, total peripheral vascular resistance) and oxygen transport (arterial oxygen content and oxygen flux) in normovolaemic dogs.
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Zarins CK, Bayne CG, Rice CL, Peters RM, Virgilio RW. Does spontaneous ventilation with IMV protect from PEEP-induced cardiac output depression? J Surg Res 1977; 22:299-304. [PMID: 402505 DOI: 10.1016/0022-4804(77)90147-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Douglas ME, Downs JB. Pulmonary function following severe acute respiratory failure and high levels of positive end-expiratory pressure. Chest 1977; 71:18-23. [PMID: 318613 DOI: 10.1378/chest.71.1.18] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In an 18-month period, we treated 561 patients with mechanical ventilation. Fifty-four (10 percent) of these patients had acute respiratory failure, requiring treatment with positive end-expiratory pressure (PEEP) in excess of 20 mm Hg (range, 20 to 40 mm Hg). All patients were allowed to breathe spontaneously between volume-limited mechanical breaths delivered at a rate sufficient to maintain an arterial pH greater than or equal to 7.35. PEEP was applied until calculated pulmonary venous admixture was minimized. Forty-three (80 percent) of these 54 patients were alive and asymptomatic three months after dischage from the hospital, and tests of pulmonary function were performed on ten patients within one year after hospitalization. Abnormalities in pulmonary function appeared to be reversible, and pulmonary function gradually approached normal within one year. It appears that neither acute respiratory failure nor exposure to high airway pressures caused significant permanent pulmonary damage in the ten patients studied.
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