Summary
Physiological alterations occur in the critical care medicine, and reflect illness. Rendering patients physiologic parameters in the range that is normal for the population is not necessarily good; it may be frankly harmful. We do not currently possess outcome-based tools that allow us to titrate physiological parameters and ensure improved outcome. It is highly unlikely that our practice will evolve to inducing anemia, hyperthermia, hypoxemia, hypercapnia and hypotension in our critically ill patients! However, evolving knowledge of the appropriate thresholds for these parameters in critically ill patients, in addition to greater understanding of the potential iatrogenic illness associated with parameter ‘normalization’, could lead to provision of enhanced patient care. In the coming years it is possible that we will redefine the ‘normal’ range for common clinical and laboratory values relating to the critically ill. We may switch to ‘context sensitive’ interpretation of parameters of illness, and manage critically ill patients accordingly.
Sommaire
Des changements physiologiques surviennent à l’USI et reflètent la maladie. Interpréter les paramètres physiologiques des patients selon les limites qui sont normales pour la population n’est pas nécessairement bon; cela peut être franchement mauvais. Nous ne possédons pas présentement d’outils basés sur les complications qui nous permettent de doser les paramètres physiologiques et d’assurer l’amélioration des résultats thérapeutiques. Il est hautement improbable que notre pratique évolue vers l’induction de l’anémie, de l’hyperthermie, l’hypoxémie, l’hypercapnie et l’hypotension chez les patient gravement malades! Toutefois, l’évolution des connaissances sur les seuils appropriés de ces paramètres chez les grands malades, en plus d’une meilleure compréhension de la maladie iatrogénique potentielle associée à la «normalisation» des paramètres, peuvent conduire à l’amélioration des soins. Dans les années à venir, il est possible que nous redéfinissions les limites «normales» des valeurs cliniques et expérimentales courantes en relation avec les grands malades. Nous pouvons adopter une interprétation «contextuelle» des paramètres de la maladie et traiter les patients gravement malades en conséquence.
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Kavanagh, B.P. Anemia, hypoxia and hypercapnia thresholds. Lessons from physiological limits in critically ill patients. Can J Anesth 46 (Suppl 5), R145–R155 (1999). https://doi.org/10.1007/BF03013190
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DOI: https://doi.org/10.1007/BF03013190