Increased FIO2 Influences SvO2 Interpretation and Accuracy of Fick-based Cardiac Output Assessment in Cardiac Surgery Patients

Abstract Background: The study aimed to reveal how the fraction of inspired oxygen (FIO2) affected the value of mixed venous oxygen saturation (SvO2) and the accuracy of Fick-equation-based cardiac output (Fick-CO). Methods: Forty-two adult patients who underwent elective cardiac surgery were enrolled and randomly divided into two groups: FIO2 <0.7 or >0.85. Under stable general anesthesia, thermodilution-derived cardiac output (TD-CO), SvO2, PvO2, hemoglobin, SaO2, PaO2, and blood pH levels were recorded before surgical incision. Results: Significant differences in FIO2 values were observed between the two groups (0.56 ±0.08 in the <70% group and 0.92 ±0.03 in the >0.85 group; p <0.0001). The increasing FIO2 values lead to increases in SvO2, PvO2, and PaO2, with little effects on cardiac output and hemoglobin levels. When comparing to TD-CO, the calculated Fick-CO in both groups had moderate Pearson correlations and similar linear regression results. Although the FIO2 <0.7 group presented a less mean bias and a smaller limits of agreement, neither group met the percentage error criteria of <30% in Bland-Altman analysis.Conclusions: Increased FIO2 may influence the interpretation of SvO2 and the exacerbation of Fick-CO estimation, which could affect clinical management. Trial Registration: ClinicalTrials.gov ID number: NCT04265924. Retrospectively registered (Date of registration: February 12, 2020).

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Right-to-left shunt determination in dog lungs under inhalation anesthesia with rebreathing and non-rebreathing system

Acta Cirurgica Brasileira ◽

10.1590/s0102-86502006000600004 ◽

2006 ◽

Vol 21 (6) ◽

pp. 374-379 ◽

Cited By ~ 1

Author(s):

André Leguthe Rosa ◽

Patrícia Cristina Azevedo Mota ◽

Yara Marcondes Machado Castiglia

Keyword(s):

Partial Pressure ◽

Carbon Dioxide Partial Pressure ◽

Partial Pressure Of Oxygen ◽

Intrapulmonary Shunt ◽

Inhalation Anesthesia ◽

Arterial Partial Pressure ◽

Venous Oxygen Saturation ◽

Fraction Of Inspired Oxygen ◽

Inspired Oxygen ◽

Mixed Venous

PURPOSE: To investigatge right-to-left shunt determination in dog lungs under inhalantion anesthesia with non-rebreathing and rebreathing systems and fraction of inspired oxygen (F I O2) of 0.9 and 0.4, respectively. METHODS: Two groups of 10 dogs each under inhalation anesthesia with sevoflurane: GI in which it was utilized non-rebreathing semiclosed system and F I O2 = 0.9, and GII in which it was utilized rebreathing semiclosed system and F I O2 = 0.4. The study parameters were: heart rate, medium arterial pressure, right-to-left intrapulmonary shunt, hematocrit, hemoglobin, arterial partial pressure of oxygen, mixed venous partial pressure of oxygen, mixed venous oxygen saturation, arterial partial pressure of carbon dioxide, partial pressure of water in the alveoli. RESULTS: Shunt results were significantly different between the two groups - GI data were higher than GII in all the evaluated moments. Hence, the group with nonrebreathing (GI) developed a superior grade of intrapulmonary shunt when compared with the rebreathing group (GII). The partial pressure of water in the alveoli was significantly higher in GII. CONCLUSION: The inhalation anesthesia with non-rebreathing system and F I O2 = 0.9 developed a higher grade of intrapulmonary right-to-left shunt when compared with the rebreathing system and F I O2 = 0.4. The higher humidity in GII contributed to the result.

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Estimation of cardiac output variations induced by hemodynamic interventions using multi-beat analysis of arterial waveform: a comparative off-line study with transesophageal Doppler method during non-cardiac surgery

Journal of Clinical Monitoring and Computing ◽

10.1007/s10877-021-00679-z ◽

2021 ◽

Author(s):

Arthur Le Gall ◽

Fabrice Vallée ◽

Jona Joachim ◽

Alex Hong ◽

Joaquim Matéo ◽

...

Keyword(s):

Cardiac Output ◽

Cardiac Surgery ◽

Fluid Challenge ◽

Percentage Error ◽

Exclusion Zone ◽

Upper Limits ◽

Before And After ◽

Transesophageal Doppler ◽

Trending Ability ◽

Arterial Wave Reflection

AbstractMulti-beat analysis (MBA) of the radial arterial pressure (AP) waveform is a new method that may improve cardiac output (CO) estimation via modelling of the confounding arterial wave reflection. We evaluated the precision and accuracy using the trending ability of the MBA method to estimate absolute CO and variations (ΔCO) during hemodynamic challenges. We reviewed the hemodynamic challenges (fluid challenge or vasopressors) performed when intra-operative hypotension occurred during non-cardiac surgery. The CO was calculated offline using transesophageal Doppler (TED) waveform (COTED) or via application of the MBA algorithm onto the AP waveform (COMBA) before and after hemodynamic challenges. We evaluated the precision and the accuracy according to the Bland & Altman method. We also assessed the trending ability of the MBA by evaluating the percentage of concordance with 15% exclusion zone between ΔCOMBA and ΔCOTED. A non-inferiority margin was set at 87.5%. Among the 58 patients included, 23 (40%) received at least 1 fluid challenge, and 46 (81%) received at least 1 bolus of vasopressors. Before treatment, the COTED was 5.3 (IQR [4.1–8.1]) l min−1, and the COMBA was 4.1 (IQR [3–5.4]) l min−1. The agreement between COTED and COMBA was poor with a 70% percentage error. The bias and lower and upper limits of agreement between COTED and COMBA were 0.9 (CI95 = 0.82 to 1.07) l min−1, −2.8 (CI95 = −2.71 to−2.96) l min−1 and 4.7 (CI95 = 4.61 to 4.86) l min−1, respectively. After hemodynamic challenge, the percentage of concordance (PC) with 15% exclusion zone for ΔCO was 93 (CI97.5 = 90 to 97)%. In this retrospective offline analysis, the accuracy, limits of agreements and percentage error between TED and MBA for the absolute estimation of CO were poor, but the MBA could adequately track induced CO variations measured by TED. The MBA needs further evaluation in prospective studies to confirm those results in clinical practice conditions.

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12 / Noninvasive cardiac output monitoring: pulse wave transit time (PWTT) versus pulse waveform analysis during elective cardiac surgery

10.26226/morressier.5aeb0ac907b0d6001a79a779 ◽

2018 ◽

Author(s):

Suraphong Lorsomradee ◽

Suraphong Lorsomradee

Keyword(s):

Cardiac Output ◽

Cardiac Surgery ◽

Pulse Wave ◽

Waveform Analysis ◽

Cardiac Output Monitoring ◽

Pulse Waveform ◽

Elective Cardiac Surgery ◽

Pulse Wave Transit Time ◽

Pulse Waveform Analysis ◽

Output Monitoring

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Recommendations for Mechanical Ventilation during Donor Care

Progress in Transplantation ◽

10.1177/152692480001000107 ◽

2000 ◽

Vol 10 (1) ◽

pp. 33-40 ◽

Cited By ~ 16

Author(s):

David J. Powner ◽

Joseph M. Darby ◽

Susan A. Stuart

Keyword(s):

Carbon Dioxide ◽

Mechanical Ventilation ◽

Cardiac Output ◽

Oxygen Uptake ◽

Tidal Volume ◽

Organ Procurement ◽

Mechanical Ventilator ◽

Positive End Expiratory Pressure ◽

Fraction Of Inspired Oxygen ◽

Inspired Oxygen

The organ procurement coordinator usually directs adjustments to the mechanical ventilator during donor care. It is often difficult to achieve optimal oxygen uptake and carbon dioxide removal while avoiding barotrauma or undesirable effects on the cardiac output. Interrelationships among a variety of ventilator parameters must be understood in order to achieve the desired goal of providing the best organs possible. These recommendations review the key ventilator parameters of tidal volume; positive end-expiratory pressure; auto–positive end-expiratory pressure; fraction of inspired oxygen; and flowrate and frequency and their interactions in controlling peak, plateau, and mean and end-expiratory airway pressures.

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Continuous Cardiac Output by using Arterial Pressure Waveform Analysis and Central Venous Oxygen Saturation during Cardiac Surgery - A case report -

Korean Journal of Anesthesiology ◽

10.4097/kjae.2007.53.1.109 ◽

2007 ◽

Vol 53 (1) ◽

pp. 109 ◽

Cited By ~ 1

Author(s):

Tae-Yop Kim ◽

Won-Kyoung Kwon ◽

Chang Yong Yoon ◽

Hae-Kyoung Kim ◽

Jun Seok Kim ◽

...

Keyword(s):

Cardiac Output ◽

Cardiac Surgery ◽

Case Report ◽

Arterial Pressure ◽

Central Venous Oxygen Saturation ◽

Waveform Analysis ◽

Pressure Waveform ◽

Central Venous ◽

Arterial Pressure Waveform ◽

Venous Oxygen Saturation

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Effect of ventilation strategy during cardiopulmonary bypass on postoperative pulmonary complications after cardiac surgery: a randomized clinical trial

Journal of Cardiothoracic Surgery ◽

10.1186/s13019-021-01699-1 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Meng-Qiu Zhang ◽

Yu-Qi Liao ◽

Hong Yu ◽

Xue-Fei Li ◽

Wei Shi ◽

...

Keyword(s):

Clinical Trial ◽

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Ideal Body Weight ◽

Pulmonary Complications ◽

Postoperative Pulmonary Complications ◽

Clinical Trial Registry ◽

Elective Cardiac Surgery ◽

Fraction Of Inspired Oxygen ◽

Grade 3

Abstract Background To determine whether maintaining ventilation during cardiopulmonary bypass (CPB) with a different fraction of inspired oxygen (FiO2) had an impact on the occurrence of postoperative pulmonary complications (PPCs). Methods A total of 413 adult patients undergoing elective cardiac surgery with CPB were randomly assigned into three groups: 138 in the NoV group (received no mechanical ventilation during CPB), 138 in the LOV group (received a tidal volume (VT) of 3–4 ml/kg of ideal body weight with the respiratory rate of 10–12 bpm, and the positive end-expiratory pressure of 5–8 cmH2O during CPB; the FiO2 was 30%), and 137 in the HOV group (received the same ventilation parameters settings as the LOV group while the FiO2 was 80%). Results The primary outcomes were the incidence and severity of PPCs during hospitalization. The composite incidence of PPCs did not significantly differ between the NoV (63%), LOV (49%) and HOV (57%) groups (P = 0.069). And there was also no difference regarding the incidence of PPCs between the non-ventilation (NoV) and ventilation (the combination of LOV and HOV) groups. The LOV group was observed a lower proportion of moderate and severe pulmonary complications (grade ≥ 3) than the NoV group (23.1% vs. 44.2%, P = 0.001). Conclusion Maintaining ventilation during CPB did not reduce the incidence of PPCs in patients undergoing cardiac surgery. Trial registration: Chinese Clinical Trial Registry ChiCTR1800015261. Prospectively registered 19 March 2018. http://www.chictr.org.cn/showproj.aspx?proj=25982

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Intraoperative Oxygen Concentration and Neurocognition after Cardiac Surgery

Anesthesiology ◽

10.1097/aln.0000000000003650 ◽

2020 ◽

Author(s):

Shahzad Shaefi ◽

Puja Shankar ◽

Ariel L. Mueller ◽

Brian P. O’Gara ◽

Kyle Spear ◽

...

Keyword(s):

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Cognitive Dysfunction ◽

Cognitive Assessment ◽

Older Patients ◽

Postoperative Cognitive Dysfunction ◽

Neurocognitive Function ◽

Secondary Outcomes ◽

Fraction Of Inspired Oxygen ◽

Inspired Oxygen

Background Despite evidence suggesting detrimental effects of perioperative hyperoxia, hyperoxygenation remains commonplace in cardiac surgery. Hyperoxygenation may increase oxidative damage and neuronal injury leading to potential differences in postoperative neurocognition. Therefore, this study tested the primary hypothesis that intraoperative normoxia, as compared to hyperoxia, reduces postoperative cognitive dysfunction in older patients having cardiac surgery. Methods A randomized double-blind trial was conducted in patients aged 65 yr or older having coronary artery bypass graft surgery with cardiopulmonary bypass. A total of 100 patients were randomized to one of two intraoperative oxygen delivery strategies. Normoxic patients (n = 50) received a minimum fraction of inspired oxygen of 0.35 to maintain a Pao2 above 70 mmHg before and after cardiopulmonary bypass and between 100 and 150 mmHg during cardiopulmonary bypass. Hyperoxic patients (n = 50) received a fraction of inspired oxygen of 1.0 throughout surgery, irrespective of Pao2 levels. The primary outcome was neurocognitive function measured on postoperative day 2 using the Telephonic Montreal Cognitive Assessment. Secondary outcomes included neurocognitive function at 1, 3, and 6 months, as well as postoperative delirium, mortality, and durations of mechanical ventilation, intensive care unit stay, and hospital stay. Results The median age was 71 yr (interquartile range, 68 to 75), and the median baseline neurocognitive score was 17 (16 to 19). The median intraoperative Pao2 was 309 (285 to 352) mmHg in the hyperoxia group and 153 (133 to 168) mmHg in the normoxia group (P < 0.001). The median Telephonic Montreal Cognitive Assessment score on postoperative day 2 was 18 (16 to 20) in the hyperoxia group and 18 (14 to 20) in the normoxia group (P = 0.42). Neurocognitive function at 1, 3, and 6 months, as well as secondary outcomes, were not statistically different between groups. Conclusions In this randomized controlled trial, intraoperative normoxia did not reduce postoperative cognitive dysfunction when compared to intraoperative hyperoxia in older patients having cardiac surgery. Although the optimal intraoperative oxygenation strategy remains uncertain, the results indicate that intraoperative hyperoxia does not worsen postoperative cognition after cardiac surgery. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

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