Skip to main content

Advertisement

Log in

Arterial oxygen tension and mortality in mechanically ventilated patients

  • Original
  • Published:
Intensive Care Medicine Aims and scope Submit manuscript

Abstract

Purpose

Early hyperoxia may be an independent risk factor for mortality in mechanically ventilated intensive care unit (ICU) patients. We examined the relationship between early arterial oxygen tension (PaO2) and in-hospital mortality.

Method

We retrospectively assessed arterial blood gases (ABG) with ‘worst’ alveolar-arterial (A-a) gradient during the first 24 h of ICU admission for all ventilated adult patients from 150 participating ICUs between 2000 and 2009. We used multivariate analysis in all patients and defined subgroups to determine the relationship between PaO2 and mortality. We also studied the relationship between worst PaO2, admission PaO2 and peak PaO2 in a random cohort of patients.

Results

We studied 152,680 patients. Their mean PaO2 was 20.3 kPa (SD 14.6) and mean inspired fraction of oxygen (FiO2) was 62% (SD 26). Worst A-a gradient ABG identified that 49.8% (76,110) had hyperoxia (PaO2 > 16 kPa). Nineteen per cent of patients died in ICU and 26% in hospital. After adjusting for site, Simplified Acute Physiology Score II (SAPS II), age, FiO2, surgical type, Glasgow Coma Scale (GCS) below 15 and year of ICU admission, there was an association between progressively lower PaO2 and increasing in-hospital mortality, but not with increasing levels of hyperoxia. Similar findings were observed with a sensitivity analysis of PaO2 derived from high FiO2 (≥50%) versus low FiO2 (<50%) and in defined subgroups. Worst PaO2 showed a strong correlation with admission PaO2 (r = 0.98) and peak PaO2 within 24 h of admission (r = 0.86).

Conclusion

We found there was an association between hypoxia and increased in-hospital mortality, but not with hyperoxia in the first 24 h in ICU and mortality in ventilated patients. Our findings differ from previous studies and suggest that the impact of early hyperoxia on mortality remains uncertain.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Similar content being viewed by others

Abbreviations

ANZ:

Australia and New Zealand

ANZICS:

Australian and New Zealand Intensive Care Society (ANZICS)

APACHE III:

Acute Physiology and Chronic Health Evaluation III

CORE:

Centre for Outcomes and Resource Evaluation

FiO2 :

Inspired fraction of oxygen

PaO2 :

Arterial oxygen tension

SAPS:

Simplified Acute Physiology Score

References

  1. Esteban A, Anzueto A, Inmaulada A, Gordo F, Apezteguia C, Palizas F, Cide D, Goldwaser R, Soto L, Bugedo G, Rodrigo C, Pimentel J, Raimondi G, Tobin MJ, for the Mechanical Ventilation International Study Group (2000) How is mechanical ventilation employed in the intensive care unit? An international utilization review. Am J Respir Crit Care Med 161:1450–1458

    Google Scholar 

  2. Rose L, Presneill JJ, Johnston L, Nelson S, Cade JF (2009) Ventilation and weaning practices in Australia and New Zealand. Anaesth Intensive Care 37:99–107

    PubMed  CAS  Google Scholar 

  3. Eastwood GM, Reade MC, Peck L, Jones D, Bellomo R (2011) Intensivists’ opinion and self-reported practice of oxygen therapy. Anaesth Intensive Care 39:122–126

    PubMed  CAS  Google Scholar 

  4. O’Driscoll, BR, Howard LS, Davison AD (2008) BTS guideline for emergency oxygen use in adult patients. Thorax 63:vi1–vi68

    Google Scholar 

  5. Austin MA, Willis KE, Blizzard L, Walters EH, Wood-Baker R (2010) Effect of high flow oxygen on mortality in chronic obstructive pulmonary disease patients in prehospital setting: randomised controlled trial. BMJ 341:c5462. doi:10.1136/bmj.c5462

  6. Altemeier WA, Sinclair SE (2007) Hyperoxia in the intensive care unit: why is more not always better. Curr Opin Crit Care 13:73–78

    Article  PubMed  Google Scholar 

  7. Kilgannon JH, Jones AE, Shapiro NI, Angelos MG, Milcarek B, Hunter K, Parrillo J, Trzeciak S (2010) Association between arterial hyperoxia following resuscitation from cardiac arrest and in-hospital mortality. JAMA 303(21):2165–2171

    Google Scholar 

  8. Fracica PJ, Knapp MJ, Piantadosi CA, Takeda K, Fulkerson WJ, Coleman RE, Wolfe WG, Crapo JD (1991) Responses of baboons to prolonged hyperoxia: physiology and qualitative pathology. J Appl Physiol 71:2352–2362

    PubMed  CAS  Google Scholar 

  9. Crapo JD, Barry BE, Foscue HA, Shelburne J (1980) Structural and biochemical changes in rat lungs occurring during exposures to lethal and adaptive doses of oxygen. Am Rev Respir Dis 122:123–143

    PubMed  CAS  Google Scholar 

  10. Lodato RF (1989) Decreased O2 consumption and cardiac output during normobaric hyperoxia in conscious dogs. J Appl Physiol 67:1551–1559

    PubMed  CAS  Google Scholar 

  11. Kavangh BP (1998) Goals and concerns for oxygenation in acute respiratory distress syndrome. Curr Opin Crit Care 4:16–20

    Article  Google Scholar 

  12. Zwemer CF, Whitesall SE, DiAlecy LG (1995) Hypoxic cardiopulmonary-cerebral resuscitation fails to improve neurological outcome following cardiac arrest in dogs. Resuscitation 29:225–236

    Article  PubMed  CAS  Google Scholar 

  13. de Jonge E, Peelen L, Keijzers PJ, Joore H, de Lange D, van der Voort PHJ, Bosman RJ, de Waal RAL, Wesselink R, de Keizer NF (2008) Association between administered oxygen, arterial partial oxygen pressure and mortality in mechanically ventilated intensive care unit patients. Crit Care 12(6):R156

    Article  PubMed  Google Scholar 

  14. Greif R, Akca O, Horn EP, Kurz A, Sessler DI (2000) Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection. Outcomes Research Group. N Engl J Med 342:161–167

    Article  PubMed  CAS  Google Scholar 

  15. Pryor KO, Fahey TJ III, Lien CA, Goldstein PA (2004) Surgical site infection and the routine use of perioperative hyperoxia in a general surgical population: a randomized controlled trial. JAMA 291:79–87

    Article  PubMed  CAS  Google Scholar 

  16. Stow PJ, Hart GK, Higlett T, George C, Herkes R, Mc William D, Bellomo R, for the ANZICS Database Management Committee (2006) Development and implementation of a high-quality clinical database: the Australian and New Zealand Intensive Care Society Adult Patient Database. J Crit Care 21:133–141

    Article  PubMed  Google Scholar 

  17. Knaus WA, Wagner DP, Draper EA, Zimmerman JE, Bergner M, Bastos PG, Sirio CA, Murphy DJ, Lotring T, Damiano A, Harrell FE (1991) The APACHE II prognostic system. Risk prediction of hospital mortality for critically ill hospitalized adults. Chest 100:1619–1636

    Article  PubMed  CAS  Google Scholar 

  18. Halpern NA, Pastores SM, Thaler HT, Greenstein RJ (2006) Changes in critical care beds and occupancy in the United States 1985–2000: differences attributable to hospital size. Crit Care Med 34:2105–2112

    Article  PubMed  Google Scholar 

  19. Moran JL, Solomon PJ (2003) Mortality and other event rates: what do they tell us about performance? Crit Care Resusc 5:292–294

    PubMed  CAS  Google Scholar 

  20. Rowan KM, Kerr JH, Major E, McPherson K, Short A, Vessey MP (1993) Intensive Care Society’s APACHE II study in Britain and Ireland—II: outcome comparisons of intensive care units after adjustment for case mix by the American APACHE II method. BMJ 307:977–981

    Article  PubMed  CAS  Google Scholar 

  21. Branson RD, Robinson BR (2011) Oxygen: when is more the enemy of good? Intensive Care Med 37:1–3

    Article  PubMed  Google Scholar 

  22. Calzia E, Ashar P, Hauser B, Matejovic M, Ballestra C, Radermacher P, Georgieff M (2010) Hyperoxia may be beneficial. Crit Care Med 30:S559–S568

    Article  Google Scholar 

  23. Mao C, Wong D, Slutsky A, Bavanagh B (1991) A quantitative assessment of how Canadian intensivists believe they utilize oxygen in the intensive care unit. Crit Care Med 27:2806–2811

    Article  Google Scholar 

  24. Askie LM, Henderson-Smart DJ, Irwig L, Simpson J (2003) Oxygen-saturation targets and outcomes in extremely preterm infants. N Eng J Med 349:959–967

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank all data collectors in the 150 participating ICUs in Australia and New Zealand for their collection of high-quality data that made this study possible. Two of the investigators (MB, RB) are supported in part by an enabling grant from the Australian National Health and Medical Research Council.

Conflict of interest

All of the authors declare they have no conflict of interest in relation to this manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Glenn Eastwood.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOC 387 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Eastwood, G., Bellomo, R., Bailey, M. et al. Arterial oxygen tension and mortality in mechanically ventilated patients. Intensive Care Med 38, 91–98 (2012). https://doi.org/10.1007/s00134-011-2419-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00134-011-2419-6

Keywords

Navigation