The online version of this article (doi:10.1186/s13613-017-0258-5) contains supplementary material, which is available to authorized users.
To evaluate the effects of acute hyperventilation on the central venous-to-arterial carbon dioxide tension difference (∆PCO2) in hemodynamically stable septic shock patients.
Eighteen mechanically ventilated septic shock patients were prospectively included in the study. We measured cardiac index (CI), ∆PCO2, oxygen consumption (VO2), central venous oxygen saturation (ScvO2), and blood gas parameters, before and 30 min after an increase in alveolar ventilation (increased respiratory rate by 10 breaths/min).
Arterial pH increased significantly (from 7.35 ± 0.07 to 7.42 ± 0.09, p < 0.001) and arterial carbon dioxide tension decreased significantly (from 44.5 [41–48] to 34 [30–38] mmHg, p < 0.001) when respiratory rate was increased. A statistically significant increase in VO2 (from 93 [76–105] to 112 [95–134] mL/min/m2, p = 0.002) was observed in parallel with the increase in alveolar ventilation. While CI remained unchanged, acute hyperventilation led to a significant increase in ∆PCO2 (from 4.7 ± 1.0 to 7.0 ± 2.6 mmHg, p < 0.001) and a significant decrease in ScvO2 (from 73 ± 6 to 67 ± 8%, p < 0.001). A good correlation was found between changes in arterial pH and changes in VO2 (r = 0.67, p = 0.002). Interestingly, we found a strong association between the increase in VO2 and the increase in ∆PCO2 (r = 0.70, p = 0.001).
Acute hyperventilation provoked a significant increase in ∆PCO2, which was the result of a significant increase in VO2 induced by hyperventilation. The clinician should be aware of the effects of acute elevation of alveolar ventilation on ∆PCO2.
Additional file 1. Manuscript data set.
Vallet B, Teboul JL, Cain S, Curtis S. Venoarterial CO(2) difference during regional ischemic or hypoxic hypoxia. J Appl Physiol. 2000;89:1317–21. PubMed
Lamia B, Monnet X, Teboul JL. Meaning of arterio–venous PCO 2 difference in circulatory shock. Minerva Anestesiol. 2006;72:597–604. PubMed
Pernat A, Weil MH, Tang W, Yamaguchi H, Pernat AM, Sun S, et al. Effects of hyper- and hypoventilation on gastric and sublingual PCO 2. J Appl Physiol. 1999;87:933–7. PubMed
Cain SM. Increased oxygen uptake with passive hyperventilation of dogs. J Appl Physiol. 1970;28:4–7. PubMed
Morel J, Gergelé L, Dominé A, Molliex S, Perrot JL, Labeille B, et al. The venous–arterial difference in CO 2 should be interpreted with caution in case of respiratory alkalosis in healthy volunteers. J Clin Monit Comput. 2016. doi: 10.1007/s10877-016-9897-6.
Mallat J, Lazkani A, Lemyze M, Pepy F, Meddour M, Gasan G, et al. Repeatability of blood gas parameters, PCO 2 gap, and PCO 2 gap to arterial-to-venous oxygen content difference in critically ill adult patients. Medicine. 2015;943:e415. CrossRef
Karetzky MS, Cain SM. Effect of carbon dioxide on oxygen uptake during hyperventilation in normal man. J Appl Physiol. 1970;28:8–12. PubMed
Dobson GP, Yamamoto E, Hochachka PW. Phosphofructokinase control in muscle: nature and reversal of pH-dependent ATP inhibition. Am J Physiol. 1986;250:71–6.
Davies SF, Iber C, Keene SA, McArthur CD, Path MJ. Effect of respiratory alkalosis during exercise on blood lactate. J Appl Physiol. 1986;61:948–52. PubMed
Plum F, Posner JB. Blood and cerebrospinal fluid lactate during hyperventilation. Am J Physiol. 1967;212:864–70. PubMed
Richardson DW, Kontos HA, Raper AJ, et al. Systemic circulatory responses to hypocapnia in man. Am J Physiol. 1972;223:1308–12. PubMed
Jakob SM, Groeneveld AB, Teboul JL. Venous–arterial CO 2 to arterial–venous O 2 difference ratio as a resuscitation target in shock states? Intensive Care Med. 2015;41:91–3. CrossRef
Teboul JL, Scheeren T. Understanding the Haldane effect. Intensive Care Med. 2017;43:936–8. CrossRef
Monnet X, Julien F, Ait-Hamou N, Lequoy M, Gosset C, Jozwiak M, et al. Lactate and venoarterial carbon dioxide difference/arterial–venous oxygen difference ratio, but not central venous oxygen saturation, predict increase in oxygen consumption in fluid responders. Crit Care Med. 2013;41:1412–20. CrossRefPubMed
Mallat J, Lemyze M, Meddour M, Pepy F, Gasan G, et al. Ratios of central venous-to-arterial carbon dioxide content or tension to arteriovenous oxygen content are better markers of global anaerobic metabolism than lactate in septic shock patients. Ann Intensive Care. 2016;6:10. CrossRefPubMedPubMedCentral
- Acute hyperventilation increases the central venous-to-arterial PCO2 difference in stable septic shock patients
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