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>Journals >Medicina Crítica >Year 2012, Issue 1

Salgado HTI, Gómez CJME, Cerón DUW
2nd place Winner to Prize «Dr. Mario Shapiro»
Relationship between intensive care admission p50 and mortality

Rev Asoc Mex Med Crit y Ter Int 2012; 26 (1)

Language: Español
References: 9
Page: 11-20
PDF: 89.43 Kb.

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In the critically ill patient frequently occur shifts in the oxyhemoglobin dissociation curve (measured by p50). This study analyzes the association among mortality rates, admission value of p50 and deviation related factors.
Material and methods: A cross-sectional and retrospective study was performed with data from patients admitted at the Hospital Español’s ICU between September 2009-June 2011. Patients were categorized according to levels of p50 (‹ 25, 25-29, › 29mmHg), lactate (‹ 2, 2-4, › 4 mmol/L) and pHa (‹ 7.35, 7.35-7.45. › 7.45).
Results: 527 out of 648 patients were included. The observed ICU and hospital mortality rates amongst the p50 subgroups was 8.5%, 12%, 31% («p» ‹ 0.001) and 23%, 22%, 41% («p» ‹ 0.001) respectively; furthermore statistically significant variations in mortality rates occurred for pHa and lactate. Statistically significant variations were found in all p50 subgroups for pHa, lactate, PaCO2, bicarbonate, carboxyhemoglobin and SAPS3 variables.
Conclusions: This study identified ICU and in-hospital mortality rate variations for patients showing deviations in the oxyhemoglobin dissociation curve; intergroups variations for pHa, lactate, PaCO2, carboxyhemoglobin and bicarbonate are consistent with p50 deviations.

Key words: Mortality, p50, pH, lactate.


  1. Woodson RD. Physiological significance of oxygen dissociation curve shifts. Critical Care Medicine 1979;7(9):368-373.

  2. Bryan-Brown CW, et al. Consumable oxygen: availability of oxygen in relation to oxyhemoglobin dissociation. Critical Care Medicine 1973;1(1):17-21.

  3. Epstein FH. Respiratory function of hemoglobin. The New England Journal of Medicine 1998;338(4):239-247.

  4. Beasley R, et al. New look at the oxyhaemoglobin dissociation curve. The Lancet 2006;367:1124-1125.

  5. Khee-Shing LM. Configuration of the hemoglobin oxygen dissociation curve demystified: a basic mathematical proof for medical and biological sciences undesgraduates. Advances in Physiology Education 2007;31:198-201.

  6. Shappell SD, et al. Adaptative, genetic and iatrogenic alterations of the oxyhemoglobin-dissociation curve. Anesthesiology 1972;37(2):127-139.

  7. Morgan TJ. The oxyhaemoglobin dissociation curve in critical illness. Critical Care and Resuscitation 1999;1:93-100.

  8. Sold MJ. Is there an optimal P50 of haemoglobin? Anaesthesia 1982;37:640-645.

  9. Riggs TE, et al. Acute changes in oxyhemoglobin affinity: Effects on oxygen transport and utilization. The Journal of Clinical Investigation 1973;52:2660-2663.

  10. Watkins GM, et al. The left shifted oxyhemoglobin curve in sepsis: a preventable defect. Annals of Surgery 1974;180(2):213-220.

>Journals >Medicina Crítica >Year 2012, Issue 1

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