Sylvain Diop, Elie Fadel, Pauline Valentini, Alexandre Thepaut, Thibaut Genty, Iolanda Ion, Filip De Somer, Jacques Thes
{"title":"Effect of Deep Hypothermia (18°C) on Dioxygen Metabolism During Pulmonary Thromboendarterectomy Surgery.","authors":"Sylvain Diop, Elie Fadel, Pauline Valentini, Alexandre Thepaut, Thibaut Genty, Iolanda Ion, Filip De Somer, Jacques Thes","doi":"10.1053/j.jvca.2024.09.013","DOIUrl":null,"url":null,"abstract":"<p><strong>Objectives: </strong>The aim of this physiological pilot study was to investigate the effect of deep hypothermia on oxygen extraction (OE) and consumption (VO<sub>2</sub>) in normothermic conditions (36-37°C), and at different stages of cooling: 30°C, 25°C, and 18°C.</p><p><strong>Design: </strong>For 3 months, a prospective study was conducted on patients who underwent pulmonary thromboendarterectomy.</p><p><strong>Settings: </strong>This was a single-center study done in a university teaching hospital.</p><p><strong>Participants: </strong>Patients who underwent pulmonary thromboendarterectomy during the inclusion period.</p><p><strong>Interventions: </strong>Hemodynamic and biological data were recorded from arterial and venous blood gas samples withdrawn first at normothermia, then at 30°C, 25°C, and 18°C.</p><p><strong>Measurements and main results: </strong>24 patients were included in the final analysis. Indexed VO<sub>2</sub> decreased from 65.9 mL to 25.1 mL of O<sub>2</sub>/min/m<sup>2</sup> between 36°C and 18°C (p < 0.001). The OE decreased from 18% to 9% between 36°C and 18°C (p < 0.001). At normal temperature and 18°C, the median venoarterial difference of O<sub>2</sub> bound to hemoglobin was 2.22 [1.68-2.58] and 0.03 mL [0.01-0.07] of O<sub>2</sub>/100 mL of blood, respectively (p < 0.001). Whereas the median venoarterial differences in dissolved O<sub>2</sub> were 0.78 [0.66-0.92] and 1.09 mL [1.03-1.32] of O<sub>2</sub>/100 mL of blood, respectively (p = 0.0013).</p><p><strong>Conclusion: </strong>There were VO<sub>2</sub> and OE decreases of more than half their baseline values at 18°C. Given that metabolic needs are essentially supplied by dissolved O<sub>2</sub> during cooling from 30°C to 18°C, the authors suggest that PaO<sub>2</sub> should be increased during the period of cooling and/or deep hypothermia to prevent hypoxia.</p>","PeriodicalId":15176,"journal":{"name":"Journal of cardiothoracic and vascular anesthesia","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of cardiothoracic and vascular anesthesia","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1053/j.jvca.2024.09.013","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ANESTHESIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Objectives: The aim of this physiological pilot study was to investigate the effect of deep hypothermia on oxygen extraction (OE) and consumption (VO2) in normothermic conditions (36-37°C), and at different stages of cooling: 30°C, 25°C, and 18°C.
Design: For 3 months, a prospective study was conducted on patients who underwent pulmonary thromboendarterectomy.
Settings: This was a single-center study done in a university teaching hospital.
Participants: Patients who underwent pulmonary thromboendarterectomy during the inclusion period.
Interventions: Hemodynamic and biological data were recorded from arterial and venous blood gas samples withdrawn first at normothermia, then at 30°C, 25°C, and 18°C.
Measurements and main results: 24 patients were included in the final analysis. Indexed VO2 decreased from 65.9 mL to 25.1 mL of O2/min/m2 between 36°C and 18°C (p < 0.001). The OE decreased from 18% to 9% between 36°C and 18°C (p < 0.001). At normal temperature and 18°C, the median venoarterial difference of O2 bound to hemoglobin was 2.22 [1.68-2.58] and 0.03 mL [0.01-0.07] of O2/100 mL of blood, respectively (p < 0.001). Whereas the median venoarterial differences in dissolved O2 were 0.78 [0.66-0.92] and 1.09 mL [1.03-1.32] of O2/100 mL of blood, respectively (p = 0.0013).
Conclusion: There were VO2 and OE decreases of more than half their baseline values at 18°C. Given that metabolic needs are essentially supplied by dissolved O2 during cooling from 30°C to 18°C, the authors suggest that PaO2 should be increased during the period of cooling and/or deep hypothermia to prevent hypoxia.
期刊介绍:
The Journal of Cardiothoracic and Vascular Anesthesia is primarily aimed at anesthesiologists who deal with patients undergoing cardiac, thoracic or vascular surgical procedures. JCVA features a multidisciplinary approach, with contributions from cardiac, vascular and thoracic surgeons, cardiologists, and other related specialists. Emphasis is placed on rapid publication of clinically relevant material.