Abstract:
OBJECTIVE:Heptafluoropropane is an inert gas commercially used as propellant for inhalers. Since heptafluoropropane can be detected in low concentrations, it could also be used as a tracer gas to measure functional residual capacity and ventilation homogeneity. The aim of the present study was to validate functional residual capacity measurements by heptafluoropropane wash-in/wash-out (0.8%) during mechanical ventilation in small, surfactant-depleted lungs using a newborn piglet model. DESIGN:Prospective laboratory and animal trial. SETTING:Animal laboratory in a university setting. SUBJECTS:Sixteen newborn piglets (age<12 hrs, median weight 1390 g [705-4200 g]) before and after surfactant depletion (Pao2<100 torr in Fio2=1.0) by lung lavage. INTERVENTIONS:Heptafluoropropane was measured with a new infrared mainstream sensor connected with the flow sensor of the Dräger Babylog 8000. Accuracy and precision of the measurement technique were tested in a mechanical lung model with a volume range from 11 to 35 mL. Reproducibility of the method and its sensitivity to detect changes of functional residual capacity were assessed in vivo by variation of ventilatory variables. MEASUREMENTS AND MAIN RESULTS:In vitro the absolute error of functional residual capacity was <1 mL (relative errors<3%) with a coefficient of variation<4%. The coefficient of variation of consecutive in vivo measurements was only slightly higher (<5.1%). Measurement of heptafluoropropane concentrations in blood showed no significant accumulation for repeated functional residual capacity measurements within short time periods. After lung lavage, the functional residual capacity decreased from 20.9 mL/kg to 14.5 mL/kg (p<.05) despite increased ventilatory pressures, and lung clearance index (p<.001) and moment ratios (p<.01) increased significantly due to uneven alveolar ventilation. In healthy lungs, the increase in peak inflation pressure and positive end-expiratory pressure by 3-4 cm H2O had only a moderate effect on functional residual capacity (20.9+/-8.6 vs. 26.0+/-11.9 mL/kg, p=.17) and no effect on ventilatory homogeneity, whereas in surfactant-depleted lungs the functional residual capacity increased from 14.5+/-6.7 mL/kg to 29.9+/-12.6 mL/kg (p<.001) and lung clearance index and moment ratios decreased significantly (p < .01). CONCLUSIONS:Heptafluoropropane is a suitable tracer gas for precise functional residual capacity measurements tested in vitro and allows for reproducible measurements in ventilated small lungs without any adverse effects on mechanical ventilation. The sensitivity of the method is sufficiently high to demonstrate the effect of changes in ventilatory settings on the functional residual capacity and ventilation homogeneity.
journal_name
Crit Care Medjournal_title
Critical care medicineauthors
Proquitté H,Kusztrich A,Auwärter V,Pragst F,Wauer RR,Schmalisch Gdoi
10.1097/01.CCM.0000220065.93507.ABsubject
Has Abstractpub_date
2006-06-01 00:00:00pages
1789-95issue
6eissn
0090-3493issn
1530-0293journal_volume
34pub_type
杂志文章abstract:OBJECTIVE:When treating patients with cardiac arrest with mild therapeutic hypothermia, a reliable and easy-to-use temperature probe is desirable. This study was conducted to investigate the accuracy and safety of tracheal temperature as a measurement of body temperature. DESIGN:Observational cohort study. SETTING:Em...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/CCM.0b013e3181e47a20
更新日期:2010-07-01 00:00:00
abstract:OBJECTIVE:To determine the sensitivity, specificity, and predictive values of cultures done with blood drawn through a central venous or arterial catheter compared with peripheral venipuncture. DESIGN:Retrospective cohort study of critically ill surgical patients in whom samples for paired cultures were drawn through ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-200201000-00002
更新日期:2002-01-01 00:00:00
abstract::Simple insertion of a nasogastric (NG) tube was successful in only 52 of 100 anesthetized intubated patients. After the larynx was manually pulled forward, the NG tube was successfully inserted in 33 patients. In the remaining 15 patients, the NG tube was inserted only with the aid of a finger or a laryngoscope used w...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-198503000-00013
更新日期:1985-03-01 00:00:00
abstract:OBJECTIVES:Extracellular mitochondrial DNA and N-formyl peptides released following tissue damage may contribute to systemic inflammation through stimulation of the innate immune system. In this review, we evaluate existing in vivo human data regarding a role for mitochondrial DNA and N-formyl peptides in producing sys...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/CCM.0000000000003381
更新日期:2018-12-01 00:00:00
abstract::Measuring gas exchange in critically ill patients can provide valuable information on their nutritional status and energy expenditure. Several semiautomated machines are available for measuring oxygen consumption (VO2) and carbon dioxide production (VCO2). This study evaluated, under controlled laboratory conditions, ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-198609000-00010
更新日期:1986-09-01 00:00:00
abstract::Given the limitations of high-dose diuretics and vasodilators and the increasing literature showing that inotropes, regardless of the dose used, have a detrimental effect on mortality, a variety of new agents are under investigation for the treatment of pulmonary and systemic congestion and restoration of cardiac outp...
journal_title:Critical care medicine
pub_type: 杂志文章,评审
doi:10.1097/01.CCM.0000296810.74724.8D
更新日期:2008-01-01 00:00:00
abstract:OBJECTIVE:Physiologic and pathologic comparison of two modes of assisted ventilation, nasal intermittent positive-pressure ventilation (NIPPV) and synchronized intermittent mandatory ventilation (SIMV), in spontaneously breathing term newborn piglets with saline lavage-induced lung injury. DESIGN:After inducing acute ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/01.CCM.0000295311.61378.7D
更新日期:2008-01-01 00:00:00
abstract:OBJECTIVE:High-frequency oscillation has been proposed for use in adult acute respiratory distress syndrome. However, limited data are available on the effect of pressure amplitude and rate (Hz) on tidal volumes delivered during high-frequency oscillation in adults. DESIGN:Prospective, animal model, lung injury study....
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-200301000-00035
更新日期:2003-01-01 00:00:00
abstract::To understand better the incidence and meaning of hyperamylasemia in the intensive care setting, cellulose acetate membrane electrophoresis was used to measure the isoenzymes of serum amylase in 192 patients with a variety of critical illnesses. Seventy of these patients had elevated serum amylase levels, but none had...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-198507000-00003
更新日期:1985-07-01 00:00:00
abstract:OBJECTIVES:To determine the rate of unplanned PICU readmissions, examine the characteristics of index admissions associated with readmission, and compare outcomes of readmissions versus index admissions. DESIGN:Retrospective cohort analysis. SETTING:Ninety North American PICUs that participated in the Virtual Pediatr...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/CCM.0b013e31829eb970
更新日期:2013-12-01 00:00:00
abstract:OBJECTIVE:To define changes in intramyocardial pH and PCO2 during cardiac arrest and resuscitation. DESIGN:Prospective and observational trial. SETTING:Mammalian research laboratory utilizing a porcine model of cardiac arrest. SUBJECTS:Sixteen domestic pigs. INTERVENTIONS:Ventricular fibrillation was induced by an ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199306000-00020
更新日期:1993-06-01 00:00:00
abstract:OBJECTIVES:Ethicists advise that life-sustaining treatment decisions should be made in keeping with patient preferences. Until recently, there has been little systematic study of the impact of patient preferences on the use of various life-sustaining treatments or the consequent cost of hospital care. This prospective ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199611000-00009
更新日期:1996-11-01 00:00:00
abstract:OBJECTIVES:To evaluate the internal consistency, validity, responsiveness, and minimal important difference of the Functional Status Score for the ICU, a physical function measure designed for the ICU. DESIGN:Clinimetric analysis. SETTINGS:Five international datasets from the United States, Australia, and Brazil. PA...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/CCM.0000000000001949
更新日期:2016-12-01 00:00:00
abstract:OBJECTIVE:Acute respiratory distress syndrome is an abrupt inflammatory illness that involves damage from reactive oxygen species. We examined the efficacy and safety of oxothiazolidine-4-carboxylic acid (OTZ), a free radical scavenger, in treating acute respiratory distress syndrome. DESIGN:Double-blind, placebo-cont...
journal_title:Critical care medicine
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1097/CCM.0B013E318164E7E4
更新日期:2008-03-01 00:00:00
abstract:OBJECTIVES:Our primary goal was to evaluate the impact on in-hospital mortality rate of adequate empirical antibiotic therapy, after controlling for confounding variables, in a cohort of patients admitted to the intensive care unit (ICU) with sepsis. The impact of adequate empirical antibiotic therapy on early (<3 days...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/01.CCM.0000098031.24329.10
更新日期:2003-12-01 00:00:00
abstract:BACKGROUND:We have previously described a method for the precise delivery of inhaled nitric oxide (iNO) via a conventional, continuous-flow, pressure-limited, time-cycled ventilator. Because of the augmented effect of iNO decreasing pulmonary vascular resistance with high-frequency oscillatory ventilation (HFOV), we de...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199911000-00038
更新日期:1999-11-01 00:00:00
abstract:OBJECTIVE:The objective of the study is to test whether multimodal magnetic resonance imaging can provide a reliable outcome prediction of the clinical status, focusing on consciousness at 1 year after severe traumatic brain injury (TBI). DESIGN:Single center prospective cohort with consecutive inclusions. SETTING:Cr...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/CCM.0b013e31819cf050
更新日期:2009-04-01 00:00:00
abstract:OBJECTIVE:To investigate whether a redistribution of blood flow from the mucosa to the muscular layer of the intestinal wall contributes to the observed increased arterial-mucosal Pco2 gradient and the decreased mucosal tonometric pH during endotoxic shock. DESIGN:A prospective, controlled, animal study. SETTING:Anim...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199608000-00013
更新日期:1996-08-01 00:00:00
abstract:OBJECTIVE:Nondepolarizing neuromuscular blocking agents are commonly used in the intensive care setting, but they have occasionally been associated with development of myopathy. In addition, diaphragmatic atrophy and a reduction in diaphragmatic force were reported after short-term controlled mechanical ventilation in ...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/01.CCM.0000245783.28478.AD
更新日期:2006-12-01 00:00:00
abstract:OBJECTIVE:To determine the significance of moderate elevations of serum troponin I in a surgical intensive care unit patient population in terms of its impact on indexes of outcome including mortality, morbidity, and hospital and intensive care unit length of stay. DESIGN:Retrospective chart review and analysis of cli...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/01.CCM.0000089931.09635.D2
更新日期:2003-11-01 00:00:00
abstract:OBJECTIVE:An increasing number of ICU patients survive and develop mental, cognitive, or physical impairments. Various interventions support recovery from this postintensive care syndrome. Physicians in charge of post-ICU patients need to know which interventions are effective. DATA SOURCES:Systematic literature searc...
journal_title:Critical care medicine
pub_type: 杂志文章,评审
doi:10.1097/CCM.0000000000000148
更新日期:2014-05-01 00:00:00
abstract:OBJECTIVE:The aim of the present study was to characterize pulmonary surfactant properties in children undergoing cardiovascular surgery with cardiopulmonary bypass. DESIGN:Prospective clinical trial. SETTING:University hospital pediatric intensive care unit. PATIENTS:Fifty pediatric patients with congenital cardiac...
journal_title:Critical care medicine
pub_type: 临床试验,杂志文章
doi:10.1097/00003246-200301000-00045
更新日期:2003-01-01 00:00:00
abstract:PURPOSE:To review the rationale for adenosine triphosphate-magnesium chloride (ATP-MgCl2) administration in shock, ischemia, and sepsis; the beneficial effects on cellular and organ functions and survival; and possible mechanisms of these effects. DATA SOURCES:Current literature review. STUDY SELECTION:Articles deeme...
journal_title:Critical care medicine
pub_type: 杂志文章,评审
doi:10.1097/00003246-199202000-00015
更新日期:1992-02-01 00:00:00
abstract:BACKGROUND:Noncuffed, percutaneously inserted central venous catheters (CVCs) are widely used and cause at least 250,000 bloodstream infections (BSIs) in U.S. hospitals each year. We report a prospective study to determine whether inflammation at the insertion site is predictive of CVC-related BSI. METHODS:Percutaneou...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-200212000-00003
更新日期:2002-12-01 00:00:00
abstract::We studied prospectively 40 critically ill neurosurgical patients who required prolonged mechanical ventilation to determine the current incidence of stress-related gastroduodenal erosions and ulcers, and to assess endoscopically the efficacy of acid-reducing prophylactic treatment. Nineteen patients were randomized t...
journal_title:Critical care medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/00003246-199003000-00004
更新日期:1990-03-01 00:00:00
abstract:OBJECTIVE:Cocaine, which first made its appearance >1,000 yrs ago, is now widely used throughout the world. The physiologic responses to cocaine may cause severe pathologic effects. This review highlights the many critical care challenges resulting from these effects. DESIGN:Historical vignettes, epidemiologic factors...
journal_title:Critical care medicine
pub_type: 杂志文章,评审
doi:10.1097/01.CCM.0000063258.68159.71
更新日期:2003-06-01 00:00:00
abstract:OBJECTIVES:Despite having dysregulated iron metabolism, critically ill patients may receive exogenous iron for the treatment of anemia. Iron is associated with increased tissue apoptosis and may facilitate bacterial growth. We hypothesized that exogenous iron administration given after the onset of sepsis would lead to...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/01.ccm.0000124878.02614.4c
更新日期:2004-05-01 00:00:00
abstract:BACKGROUND AND METHODS:To determine the effects of reduced cerebral perfusion pressures produced by hemorrhage alone or in combination with intracranial hypertension on thromboxane A2 (TxA2) production, we undertook a randomized study in 38 anesthetized, mongrel dogs. Animals were subjected to 30 mins of hemorrhagic sh...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199104000-00013
更新日期:1991-04-01 00:00:00
abstract:OBJECTIVE:To define the occurrence rate of acute respiratory distress syndrome (ARDS) using established criteria in a well-defined general patient population, to study the clinical course of ARDS when patients were ventilated using a "lung-protective" strategy, and to define the total costs of care. DESIGN:A 3-yr (199...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199911000-00008
更新日期:1999-11-01 00:00:00
abstract:OBJECTIVE:To examine the pulmonary and cardiac function of children who survived an episode of acute hypoxemic respiratory failure. DESIGN:Descriptive cohort analysis. SETTING:Pediatric clinical research center of a university hospital. PATIENTS:Utilizing the criteria of PaO2 < 75 torr (< 10 kPa) with an FIO2 of > 0...
journal_title:Critical care medicine
pub_type: 杂志文章
doi:10.1097/00003246-199601000-00024
更新日期:1996-01-01 00:00:00