Frank Bloos | University Hospital Jena (original) (raw)
Papers by Frank Bloos
German medical science : GMS e-journal, 2017
Quality improvement in medicine is depending on measurement of relevant quality indicators. The q... more Quality improvement in medicine is depending on measurement of relevant quality indicators. The quality indicators for intensive care medicine of the German Interdisciplinary Society of Intensive Care Medicine (DIVI) from the year 2013 underwent a scheduled evaluation after three years. There were major changes in several indicators but also some indicators were changed only minimally. The focus on treatment processes like ward rounds, management of analgesia and sedation, mechanical ventilation and weaning, as well as the number of 10 indicators were not changed. Most topics remained except for early mobilization which was introduced instead of hypothermia following resuscitation. Infection prevention was added as an outcome indicator. These quality indicators are used in the peer review in intensive care, a method endorsed by the DIVI. A validity period of three years is planned for the quality indicators.
European Journal of Intensive Care Medicine
German medical science : GMS e-journal, 2014
Quality improvement and safety in intensive care are rapidly evolving topics. However, there is n... more Quality improvement and safety in intensive care are rapidly evolving topics. However, there is no gold standard for assessing quality improvement in intensive care medicine yet. In 2007 a pilot project in German intensive care units (ICUs) started using voluntary peer reviews as an innovative tool for quality assessment and improvement. We describe the method of voluntary peer review and assessed its feasibility by evaluating anonymized peer review reports and analysed the thematic clusters highlighted in these reports. Retrospective data analysis from 22 anonymous reports of peer reviews. All ICUs - representing over 300 patient beds - had undergone voluntary peer review. Data were retrieved from reports of peers of the review teams and representatives of visited ICUs. Data were analysed with regard to number of topics addressed and results of assessment questionnaires. Reports of strengths, weaknesses, opportunities and threats (SWOT reports) of these ICUs are presented. External...
German medical science : GMS e-journal, 2013
Quality indicators are key elements of quality management. The quality indicators for intensive c... more Quality indicators are key elements of quality management. The quality indicators for intensive care medicine of the German Interdisciplinary Society of Intensive Care Medicine (DIVI) from the year 2010 were recently evaluated when their validity time expired after two years. Overall one indicator was replaced and further three were in part changed. The former indicator I "elevation of head of bed" was replaced by the indicator "Daily multi-professional ward rounds with the documentation of daily therapy goals" and added to the indicator IV "Weaning and other measures to prevent ventilator associated pneumonias (short: Weaning/VAP Bundle)" (VAP = ventilator-associated pneumonia) which aims at the reduction of VAP incidence. The indicator VIII "Documentation of structured relative-/next-of-kin communication" was refined. The indicator X "Direction of the ICU by a specially trained certified intensivist with no other clinical duties in a de...
PloS one, 2012
Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based meth... more Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis. This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO(®)) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p<0.01). PCR median time to result was dependent on tech...
Encyclopedia of Intensive Care Medicine, 2012
Virulence, 2013
Fast and appropriate therapy is the cornerstone in the therapy of sepsis. However, the discrimina... more Fast and appropriate therapy is the cornerstone in the therapy of sepsis. However, the discrimination of sepsis from non-infectious causes of inflammation may be difficult. Biomarkers have been suggested to aid physicians in this decision. There is currently no biochemical technique available which alone allows a rapid and reliable discrimination between sepsis and non-infectious inflammation. Procalcitonin (PCT) is currently the most investigated biomarker for this purpose. C-reactive protein and interleukin 6 perform inferior to PCT in most studies and their value in diagnosing sepsis is not defined. All biomarkers including PCT are also released after various non-infectious inflammatory impacts. This shortcoming needs to be taken into account when biomarkers are used to aid the physician in the diagnosis of sepsis. Polymerase chain reaction (PCR) based pathogen detection may improve time to adequate therapy but cannot rule out the presence of infection when negative.
Journal of critical care, Jan 30, 2014
Current guidelines and most trials do not consider elevated lactate (Lac) serum concentrations wh... more Current guidelines and most trials do not consider elevated lactate (Lac) serum concentrations when grading sepsis severity. We therefore assessed the association of different types of circulatory dysfunction regarding presence of hyperlactatemia and need for vasopressor support with clinical presentation and outcome of sepsis. In a secondary analysis of a prospective observational multicenter cohort study, 988 patients with severe sepsis were investigated regarding vasopressor support, Lac levels, and outcome. Twenty-eight-day mortality regarding shock or hyperlactatemia was as follows: hyperlactatemia more than 2.5 mmol/L and septic shock (tissue dysoxic shock): 451 patients with a mortality of 44.8%; hyperlactatemia without vasopressor need (cryptic shock): 72 patients, mortality 35.3%; no hyperlactatemia with vasopressor need (vasoplegic shock): 331 patients, mortality 27.7%; and absence of hyperlactemia or overt shock (severe sepsis): 134 patients, mortality 14.2% (P < .001)...
The Journal of Emergency Medicine, 2014
Journal of Critical Care, 2013
Journal of Critical Care, 2013
Purpose: The purposes of this study were to calculate attributable costs of candidemia in patient... more Purpose: The purposes of this study were to calculate attributable costs of candidemia in patients with severe sepsis and to obtain preliminary data regarding the potential effects of polymerase chain reaction-based pathogen detection on antifungal therapy for these patients. Methods: Patients treated between 2004 and 2010 because of severe sepsis were included into this retrospective analysis. The hospital management provided annual fixed costs per patient-day; data for variable intensive care unit costs were taken from the literature. Multiplex polymerase chain reaction (PCR) was used (VYOO®, SIRS-Lab, Jena, Germany) for pathogen detection in the blood. Results: Thirty-two patients with candidemia were identified. Of 874 patients with sepsis, propensity score matching found 32 corresponding patients with sepsis but without candida infection but similar risk factors for developing candidemia. Attributable costs of candidemia were 7713.79 Euro (cost increase, 19.4%). Initiation of antifungal therapy was reduced from 67.5 (52.4, 90) hours in the group, where candida infection was determined by blood culture, to 31.0 (28.0, 37.5; P b .01) hours after detection by multiplex PCR. Conclusions: Candidemia increases costs of care in patients with septic shock. Polymerase chain reaction-based pathogen detection significantly reduces the time to initiation of antifungal therapy. This might impact on the clinical course of the disease but need to be confirmed in further trials.
Intensive Care Medicine, 2005
Intensive Care Medicine, 2010
Objective: Moxifloxacin is an 8-methoxy quinolone with a broad range of activity against clinical... more Objective: Moxifloxacin is an 8-methoxy quinolone with a broad range of activity against clinically important pathogens. Therefore it is frequently administered in severe respiratory tract infections. Continuous venovenous haemodiafiltration (CVVHDF) is an important extracorporeal renal replacement therapy for intensive care patients suffering from sepsis and multiple organ failure. The aim of this study was to investigate the pharmacokinetics of intravenous moxifloxacin in anuric critically ill patients undergoing CVVHDF.
Intensive Care Medicine, 2010
A multicenter trial to compare blood culture with polymerase chain reaction in severe human sepsis
Critical Care, 2014
Introduction: Current sepsis guidelines recommend antimicrobial treatment (AT) within one hour af... more Introduction: Current sepsis guidelines recommend antimicrobial treatment (AT) within one hour after onset of sepsis-related organ dysfunction (OD) and surgical source control within 12 hours. The objective of this study was to explore the association between initial infection management according to sepsis treatment recommendations and patient outcome. Methods: In a prospective observational multi-center cohort study in 44 German ICUs, we studied 1,011 patients with severe sepsis or septic shock regarding times to AT, source control, and adequacy of AT. Primary outcome was 28-day mortality. Results: Median time to AT was 2.1 (IQR 0.8 -6.0) hours and 3 hours (-0.1 -13.7) to surgical source control. Only 370 (36.6%) patients received AT within one hour after OD in compliance with recommendation. Among 422 patients receiving surgical or interventional source control, those who received source control later than 6 hours after onset of OD had a significantly higher 28-day mortality than patients with earlier source control (42.9% versus 26.7%, P <0.001). Time to AT was significantly longer in ICU and hospital non-survivors; no linear relationship was found between time to AT and 28-day mortality. Regardless of timing, 28-day mortality rate was lower in patients with adequate than non-adequate AT (30.3% versus 40.9%, P < 0.001).
Critical Care, 2008
Critical Care 2008, 12(Suppl 5):P1 (doi: 10.1186/cc7034)
Critical Care, 2011
Introduction: A semi-upright position in ventilated patients is recommended to prevent ventilator... more Introduction: A semi-upright position in ventilated patients is recommended to prevent ventilator-associated pneumonia (VAP) and is one of the components in the Ventilator Bundle of the Institute for Health Care Improvement. This recommendation, however, is not an evidence-based one.
Critical Care, 2011
Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II ce... more Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II cells (A549). To study in vitro the direct influence of alveolar type II cells on mechanical stretch. Methods A549 were treated with different doses of lipopolysaccharide (LPS), 0 ng/ml, 1 ng/ml, 10 ng/ml, 100 ng/ml, 1000 ng/ml, and then A549 were lengthened 5%, 15%, 30% using a FLEXCELL tension unit 4000, a vacuum-driven device that applies strain to cells, which were cultured in six-well plates coated with collagen-I, and 12 cycles/min for 4 hours. Apoptosis was measured using the flow cytometry method that measures annexin V and propidium iodide (PI) staining. The morphological changes of apoptotic cells were observed by transmission electron microscope. Results Apoptosis could be induced in alveolar type II cells (A549) by mechanical stretch. The percentage of annexin V + PI cells increased after being treated with cyclic stretch for 4 hours by 5%, 15%, 30% in all groups. The morphological features of apoptotic cells demonstrated by transmission electron microscope were as follows: shrinkage of the cell, chromatin condensation and aggregation under the nuclear membrane as a crescent or lump, membrane-encapsulated nuclear fragment or cell organ formed by invagination of the cell membrane, and apoptotic body formation followed by vacuolization. Conclusion Apoptosis induced by mechanical stretch and LPS is dose dependent. Mechanical stretch aggravates apoptosis especially in cells treated with LPS. Annexin V and PI double staining is a specific, sensitive, and quantitative method for analyzing apoptotic cells. It is also helpful to clarify the protective mechanism of low-volume ventilation in ARDS. PaO 2 /FiO 2 430 [421; 440] # 380 [349; 397] 165 [68; 289] # C (ml/cmH 2 O) 28 [24; 32]* 18 [16; 21]* 12 [8; 17]* R i (cmH 2 O/l/s) 4.1 [3.9; 4.5] 4.5 [4.3; 5.1] 5.1 [3.7; 7.9] # P < 0.05 control vs 24-hour peritonitis, *P < 0.05 control vs 12-hour and 24-hour peritonitis.
Anesthesiology, 1988
The hemodynamic and metabolic effects of 90 minutes normobaric hyperoxia were studied in 20 criti... more The hemodynamic and metabolic effects of 90 minutes normobaric hyperoxia were studied in 20 critically ill patients (11 septic, 9 nonseptic) requiring mechanical ventilation with inspired O2 fraction (FIO2) less than 0.40. Thirty minutes after increasing the FIO2 to 1.0, arterial PO2 had increased from about 100 to about 400 mm Hg, and whole body oxygen uptake (VO2) was decreased 10 percent (p less than 0.05) due to an 18 percent decrease in O2 extraction ratio. During the subsequent 60 minutes of hyperoxia, there was no further significant change in VO2. Cardiac index did not change in hyperoxia, but it increased 10 percent (p less than 0.05) in recovery as systemic vascular resistance decreased. VO2 returned to baseline after 30 minutes recovery at original FIO2 due to increased O2 extraction as well as the increased cardiac output. The decrease in VO2 without a decrease in O2 delivery may reflect maldistribution of blood flow and functional O2 shunting to protect tissue from unphysiologically high PO2. While brief oxygenation is advisable before periods of hypoventilation, the present data suggest that hyperoxic ventilation in these patients with already adequate O2 delivery was counterproductive.
German medical science : GMS e-journal, 2017
Quality improvement in medicine is depending on measurement of relevant quality indicators. The q... more Quality improvement in medicine is depending on measurement of relevant quality indicators. The quality indicators for intensive care medicine of the German Interdisciplinary Society of Intensive Care Medicine (DIVI) from the year 2013 underwent a scheduled evaluation after three years. There were major changes in several indicators but also some indicators were changed only minimally. The focus on treatment processes like ward rounds, management of analgesia and sedation, mechanical ventilation and weaning, as well as the number of 10 indicators were not changed. Most topics remained except for early mobilization which was introduced instead of hypothermia following resuscitation. Infection prevention was added as an outcome indicator. These quality indicators are used in the peer review in intensive care, a method endorsed by the DIVI. A validity period of three years is planned for the quality indicators.
European Journal of Intensive Care Medicine
German medical science : GMS e-journal, 2014
Quality improvement and safety in intensive care are rapidly evolving topics. However, there is n... more Quality improvement and safety in intensive care are rapidly evolving topics. However, there is no gold standard for assessing quality improvement in intensive care medicine yet. In 2007 a pilot project in German intensive care units (ICUs) started using voluntary peer reviews as an innovative tool for quality assessment and improvement. We describe the method of voluntary peer review and assessed its feasibility by evaluating anonymized peer review reports and analysed the thematic clusters highlighted in these reports. Retrospective data analysis from 22 anonymous reports of peer reviews. All ICUs - representing over 300 patient beds - had undergone voluntary peer review. Data were retrieved from reports of peers of the review teams and representatives of visited ICUs. Data were analysed with regard to number of topics addressed and results of assessment questionnaires. Reports of strengths, weaknesses, opportunities and threats (SWOT reports) of these ICUs are presented. External...
German medical science : GMS e-journal, 2013
Quality indicators are key elements of quality management. The quality indicators for intensive c... more Quality indicators are key elements of quality management. The quality indicators for intensive care medicine of the German Interdisciplinary Society of Intensive Care Medicine (DIVI) from the year 2010 were recently evaluated when their validity time expired after two years. Overall one indicator was replaced and further three were in part changed. The former indicator I "elevation of head of bed" was replaced by the indicator "Daily multi-professional ward rounds with the documentation of daily therapy goals" and added to the indicator IV "Weaning and other measures to prevent ventilator associated pneumonias (short: Weaning/VAP Bundle)" (VAP = ventilator-associated pneumonia) which aims at the reduction of VAP incidence. The indicator VIII "Documentation of structured relative-/next-of-kin communication" was refined. The indicator X "Direction of the ICU by a specially trained certified intensivist with no other clinical duties in a de...
PloS one, 2012
Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based meth... more Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis. This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO(®)) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p<0.01). PCR median time to result was dependent on tech...
Encyclopedia of Intensive Care Medicine, 2012
Virulence, 2013
Fast and appropriate therapy is the cornerstone in the therapy of sepsis. However, the discrimina... more Fast and appropriate therapy is the cornerstone in the therapy of sepsis. However, the discrimination of sepsis from non-infectious causes of inflammation may be difficult. Biomarkers have been suggested to aid physicians in this decision. There is currently no biochemical technique available which alone allows a rapid and reliable discrimination between sepsis and non-infectious inflammation. Procalcitonin (PCT) is currently the most investigated biomarker for this purpose. C-reactive protein and interleukin 6 perform inferior to PCT in most studies and their value in diagnosing sepsis is not defined. All biomarkers including PCT are also released after various non-infectious inflammatory impacts. This shortcoming needs to be taken into account when biomarkers are used to aid the physician in the diagnosis of sepsis. Polymerase chain reaction (PCR) based pathogen detection may improve time to adequate therapy but cannot rule out the presence of infection when negative.
Journal of critical care, Jan 30, 2014
Current guidelines and most trials do not consider elevated lactate (Lac) serum concentrations wh... more Current guidelines and most trials do not consider elevated lactate (Lac) serum concentrations when grading sepsis severity. We therefore assessed the association of different types of circulatory dysfunction regarding presence of hyperlactatemia and need for vasopressor support with clinical presentation and outcome of sepsis. In a secondary analysis of a prospective observational multicenter cohort study, 988 patients with severe sepsis were investigated regarding vasopressor support, Lac levels, and outcome. Twenty-eight-day mortality regarding shock or hyperlactatemia was as follows: hyperlactatemia more than 2.5 mmol/L and septic shock (tissue dysoxic shock): 451 patients with a mortality of 44.8%; hyperlactatemia without vasopressor need (cryptic shock): 72 patients, mortality 35.3%; no hyperlactatemia with vasopressor need (vasoplegic shock): 331 patients, mortality 27.7%; and absence of hyperlactemia or overt shock (severe sepsis): 134 patients, mortality 14.2% (P < .001)...
The Journal of Emergency Medicine, 2014
Journal of Critical Care, 2013
Journal of Critical Care, 2013
Purpose: The purposes of this study were to calculate attributable costs of candidemia in patient... more Purpose: The purposes of this study were to calculate attributable costs of candidemia in patients with severe sepsis and to obtain preliminary data regarding the potential effects of polymerase chain reaction-based pathogen detection on antifungal therapy for these patients. Methods: Patients treated between 2004 and 2010 because of severe sepsis were included into this retrospective analysis. The hospital management provided annual fixed costs per patient-day; data for variable intensive care unit costs were taken from the literature. Multiplex polymerase chain reaction (PCR) was used (VYOO®, SIRS-Lab, Jena, Germany) for pathogen detection in the blood. Results: Thirty-two patients with candidemia were identified. Of 874 patients with sepsis, propensity score matching found 32 corresponding patients with sepsis but without candida infection but similar risk factors for developing candidemia. Attributable costs of candidemia were 7713.79 Euro (cost increase, 19.4%). Initiation of antifungal therapy was reduced from 67.5 (52.4, 90) hours in the group, where candida infection was determined by blood culture, to 31.0 (28.0, 37.5; P b .01) hours after detection by multiplex PCR. Conclusions: Candidemia increases costs of care in patients with septic shock. Polymerase chain reaction-based pathogen detection significantly reduces the time to initiation of antifungal therapy. This might impact on the clinical course of the disease but need to be confirmed in further trials.
Intensive Care Medicine, 2005
Intensive Care Medicine, 2010
Objective: Moxifloxacin is an 8-methoxy quinolone with a broad range of activity against clinical... more Objective: Moxifloxacin is an 8-methoxy quinolone with a broad range of activity against clinically important pathogens. Therefore it is frequently administered in severe respiratory tract infections. Continuous venovenous haemodiafiltration (CVVHDF) is an important extracorporeal renal replacement therapy for intensive care patients suffering from sepsis and multiple organ failure. The aim of this study was to investigate the pharmacokinetics of intravenous moxifloxacin in anuric critically ill patients undergoing CVVHDF.
Intensive Care Medicine, 2010
A multicenter trial to compare blood culture with polymerase chain reaction in severe human sepsis
Critical Care, 2014
Introduction: Current sepsis guidelines recommend antimicrobial treatment (AT) within one hour af... more Introduction: Current sepsis guidelines recommend antimicrobial treatment (AT) within one hour after onset of sepsis-related organ dysfunction (OD) and surgical source control within 12 hours. The objective of this study was to explore the association between initial infection management according to sepsis treatment recommendations and patient outcome. Methods: In a prospective observational multi-center cohort study in 44 German ICUs, we studied 1,011 patients with severe sepsis or septic shock regarding times to AT, source control, and adequacy of AT. Primary outcome was 28-day mortality. Results: Median time to AT was 2.1 (IQR 0.8 -6.0) hours and 3 hours (-0.1 -13.7) to surgical source control. Only 370 (36.6%) patients received AT within one hour after OD in compliance with recommendation. Among 422 patients receiving surgical or interventional source control, those who received source control later than 6 hours after onset of OD had a significantly higher 28-day mortality than patients with earlier source control (42.9% versus 26.7%, P <0.001). Time to AT was significantly longer in ICU and hospital non-survivors; no linear relationship was found between time to AT and 28-day mortality. Regardless of timing, 28-day mortality rate was lower in patients with adequate than non-adequate AT (30.3% versus 40.9%, P < 0.001).
Critical Care, 2008
Critical Care 2008, 12(Suppl 5):P1 (doi: 10.1186/cc7034)
Critical Care, 2011
Introduction: A semi-upright position in ventilated patients is recommended to prevent ventilator... more Introduction: A semi-upright position in ventilated patients is recommended to prevent ventilator-associated pneumonia (VAP) and is one of the components in the Ventilator Bundle of the Institute for Health Care Improvement. This recommendation, however, is not an evidence-based one.
Critical Care, 2011
Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II ce... more Objective To examine the effects of short-term cyclic stretch on apoptosis in alveolar type II cells (A549). To study in vitro the direct influence of alveolar type II cells on mechanical stretch. Methods A549 were treated with different doses of lipopolysaccharide (LPS), 0 ng/ml, 1 ng/ml, 10 ng/ml, 100 ng/ml, 1000 ng/ml, and then A549 were lengthened 5%, 15%, 30% using a FLEXCELL tension unit 4000, a vacuum-driven device that applies strain to cells, which were cultured in six-well plates coated with collagen-I, and 12 cycles/min for 4 hours. Apoptosis was measured using the flow cytometry method that measures annexin V and propidium iodide (PI) staining. The morphological changes of apoptotic cells were observed by transmission electron microscope. Results Apoptosis could be induced in alveolar type II cells (A549) by mechanical stretch. The percentage of annexin V + PI cells increased after being treated with cyclic stretch for 4 hours by 5%, 15%, 30% in all groups. The morphological features of apoptotic cells demonstrated by transmission electron microscope were as follows: shrinkage of the cell, chromatin condensation and aggregation under the nuclear membrane as a crescent or lump, membrane-encapsulated nuclear fragment or cell organ formed by invagination of the cell membrane, and apoptotic body formation followed by vacuolization. Conclusion Apoptosis induced by mechanical stretch and LPS is dose dependent. Mechanical stretch aggravates apoptosis especially in cells treated with LPS. Annexin V and PI double staining is a specific, sensitive, and quantitative method for analyzing apoptotic cells. It is also helpful to clarify the protective mechanism of low-volume ventilation in ARDS. PaO 2 /FiO 2 430 [421; 440] # 380 [349; 397] 165 [68; 289] # C (ml/cmH 2 O) 28 [24; 32]* 18 [16; 21]* 12 [8; 17]* R i (cmH 2 O/l/s) 4.1 [3.9; 4.5] 4.5 [4.3; 5.1] 5.1 [3.7; 7.9] # P < 0.05 control vs 24-hour peritonitis, *P < 0.05 control vs 12-hour and 24-hour peritonitis.
Anesthesiology, 1988
The hemodynamic and metabolic effects of 90 minutes normobaric hyperoxia were studied in 20 criti... more The hemodynamic and metabolic effects of 90 minutes normobaric hyperoxia were studied in 20 critically ill patients (11 septic, 9 nonseptic) requiring mechanical ventilation with inspired O2 fraction (FIO2) less than 0.40. Thirty minutes after increasing the FIO2 to 1.0, arterial PO2 had increased from about 100 to about 400 mm Hg, and whole body oxygen uptake (VO2) was decreased 10 percent (p less than 0.05) due to an 18 percent decrease in O2 extraction ratio. During the subsequent 60 minutes of hyperoxia, there was no further significant change in VO2. Cardiac index did not change in hyperoxia, but it increased 10 percent (p less than 0.05) in recovery as systemic vascular resistance decreased. VO2 returned to baseline after 30 minutes recovery at original FIO2 due to increased O2 extraction as well as the increased cardiac output. The decrease in VO2 without a decrease in O2 delivery may reflect maldistribution of blood flow and functional O2 shunting to protect tissue from unphysiologically high PO2. While brief oxygenation is advisable before periods of hypoventilation, the present data suggest that hyperoxic ventilation in these patients with already adequate O2 delivery was counterproductive.