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Liu S, Kohler A, Langer R, Jakob MO, Salm L, Blank A, Beldi G, Jakob SM. Hepatic blood flow regulation but not oxygen extraction capability is impaired in prolonged experimental abdominal sepsis. Am J Physiol Gastrointest Liver Physiol 2022; 323:G348-G361. [PMID: 36044679 DOI: 10.1152/ajpgi.00109.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Impaired oxygen utilization has been proposed to play a significant role in sepsis-induced liver dysfunction, but its magnitude and temporal course during prolonged resuscitation is controversial. The aim of this study is to evaluate the capability of the liver to increase oxygen extraction in sepsis during repeated acute portal vein blood flow reduction. Twenty anesthetized and mechanically ventilated pigs with hepatic hemodynamic monitoring were randomized to fecal peritonitis or controls (n = 10, each). After 8-h untreated sepsis, the animals were resuscitated for three days. The ability to increase hepatic O2 extraction was evaluated by repeated, acute decreases in hepatic oxygen delivery (Do2) via reduction of portal flow. Blood samples for liver function and liver biopsies were obtained repeatedly. Although liver function tests, ATP content, and Do2 remained unaltered, there were signs of liver injury in blood samples and overt liver cell necrosis in biopsies. With acute portal vein occlusion, hepatic Do2 decreased more in septic animals compared with controls [max. decrease: 1.66 ± 0.68 mL/min/kg in sepsis vs. 1.19 ± 0.42 mL/min/kg in controls; portal venous flow (Qpv) reduction-sepsis interaction: P = 0.028]. Hepatic arterial buffer response (HABR) was impaired but recovered after 3-day resuscitation, whereas hepatic oxygen extraction increased similarly during the procedures in both groups (max. increase: 0.27 ± 0.13 in sepsis vs. 0.18 ± 0.09 in controls; all P > 0.05). Our data indicate maintained capacity of the liver to acutely increase O2 extraction, whereas blood flow regulation is transiently impaired with the potential to contribute to liver injury in sepsis.NEW & NOTEWORTHY The capacity to acutely increase hepatic O2 extraction with portal flow reduction is maintained in sepsis with accompanying liver injury, but hepatic blood flow regulation is impaired.
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Affiliation(s)
- Shengchen Liu
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Cardio-thoracic Surgery, Nanjing First Hospital, Nanjing Medical University, Nanjing, People's Republic of China.,Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Andreas Kohler
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Rupert Langer
- Institute of Pathology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Manuel O Jakob
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Lilian Salm
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Annika Blank
- Institute of Pathology, Triemlispital Zürich, Zürich, Switzerland
| | - Guido Beldi
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Stephan M Jakob
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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Kiers HD, Pickkers P, Kox M. Hypoxemia in the presence or absence of systemic inflammation does not increase blood lactate levels in healthy volunteers. J Crit Care 2022; 71:154116. [PMID: 35872501 DOI: 10.1016/j.jcrc.2022.154116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 06/17/2022] [Accepted: 07/11/2022] [Indexed: 10/17/2022]
Abstract
PURPOSE Elevated lactate levels are a sign of critical illness and may result from insufficient oxygen delivery. We investigated whether hypoxemia and/or systemic inflammation, results in increased lactate levels in healthy volunteers. MATERIALS AND METHODS 30 healthy volunteers were exposed to either 3.5 h of hypoxemia (FiO2 ± 11.5%), normoxemic endotoxemia (FiO2 21%, administration of 2 ng/kg endotoxin), or hypoxemic endotoxemia (n = 10 per group). Blood lactate, hemoglobin, SpO2, PaO2, PaCO2, pH, and hemodynamic parameters were serially measured. RESULTS Hypoxemic treatment resulted in lower SpO2 (81.7 ± 2.6 and 81.4 ± 2.4% in the hypoxemia and hypoxemic endotoxemia groups, respectively) and hyperventilation with a PaCO2 decrease of 0.8 ± 0.5 and 1.5 ± 0.6 kPa and an increase in pH. Arterial oxygen content (CaO2) decreased by 20.5 ± 2.9 and 23.5 ± 4.4%, respectively. Lactate levels were slightly, but significantly higher in both hypoxemic groups compared with the normoxemic endotoxemia group over time (p < 0.0001 for both groups), but remained below 2.3 mmol/L in all subjects. Whereas PaO2 and SpO2 did not correlate with lactate levels, PaCO2, pH and CaO2 did. CONCLUSIONS Hypoxemia, in the absence or presence of inflammation does not result in relevant increases of lactate. The small increases in lactate observed are likely to be due to hyperventilation-related decreases in glycolysis.
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Affiliation(s)
- H D Kiers
- Department of Intensive Care Medicine, Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands; Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Nijmegen, the Netherlands.
| | - P Pickkers
- Department of Intensive Care Medicine, Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands; Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Nijmegen, the Netherlands.
| | - M Kox
- Department of Intensive Care Medicine, Radboudumc, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands; Radboud Center for Infectious Diseases (RCI), Radboud University Medical Center, Nijmegen, the Netherlands.
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Zhang J, Cui Y, Ma, MD Z, Luo Y, Chen X, Li J. Energy and Protein Requirements in Children Undergoing Cardiopulmonary Bypass Surgery: Current Problems and Future Direction. JPEN J Parenter Enteral Nutr 2018; 43:54-62. [PMID: 30070710 DOI: 10.1002/jpen.1314] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Accepted: 05/16/2018] [Indexed: 01/10/2023]
Affiliation(s)
- Jian Zhang
- Clinical Physiology Research Laboratory Capital Institute of Pediatrics Beijing China
| | - Yan‐Qin Cui
- Cardiac Intensive Care Unit Guangzhou Women and Children's Medical Center Guangdong Province China
| | - Ze‐Ming Ma, MD
- Department of Cardiac Surgery Children's Hospital affiliated to Capital Institute of Pediatrics Beijing China
| | - Yi Luo
- Department of Cardiac Surgery Children's Hospital affiliated to Capital Institute of Pediatrics Beijing China
| | - Xin‐Xin Chen
- Department of Cardiac Surgery Guangzhou Women and Children's Medical Center Guangdong Province China
| | - Jia Li
- Clinical Physiology Research Laboratory Capital Institute of Pediatrics Beijing China
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Mehta NM. The Goldilocks conundrum for optimal macronutrient delivery in the PICU--too much, too little, or just right? JPEN J Parenter Enteral Nutr 2012; 37:178-80. [PMID: 22961724 DOI: 10.1177/0148607112459906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Nilesh M Mehta
- Division of Critical Care Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Massachusetts, USA.
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Conti-Patara A, de Araújo Caldeira J, de Mattos-Junior E, de Carvalho HDS, Reinoldes A, Pedron BG, Patara M, Francisco Talib MS, Faustino M, de Oliveira CM, Cortopassi SRG. Changes in tissue perfusion parameters in dogs with severe sepsis/septic shock in response to goal-directed hemodynamic optimization at admission to ICU and the relation to outcome. J Vet Emerg Crit Care (San Antonio) 2012; 22:409-18. [PMID: 22731982 DOI: 10.1111/j.1476-4431.2012.00769.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 05/14/2012] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate the changes in tissue perfusion parameters in dogs with severe sepsis/septic shock in response to goal-directed hemodynamic optimization in the ICU and their relation to outcome. DESIGN Prospective observational study. SETTING ICU of a veterinary university medical center. ANIMALS Thirty dogs with severe sepsis or septic shock caused by pyometra who underwent surgery and were admitted to the ICU. MEASUREMENTS AND MAIN RESULTS Severe sepsis was defined as the presence of sepsis and sepsis-induced dysfunction of one or more organs. Septic shock was defined as the presence of severe sepsis plus hypotension not reversed with fluid resuscitation. After the presumptive diagnosis of sepsis secondary to pyometra, blood samples were collected and clinical findings were recorded. Volume resuscitation with 0.9% saline solution and antimicrobial therapy were initiated. Following abdominal ultrasonography and confirmation of increased uterine volume, dogs underwent corrective surgery. After surgery, the animals were admitted to the ICU, where resuscitation was guided by the clinical parameters, central venous oxygen saturation (ScvO(2)), lactate, and base deficit. Between survivors and nonsurvivors it was observed that the ScvO(2), lactate, and base deficit on ICU admission were each related independently to death (P = 0.001, P = 0.030, and P < 0.001, respectively). ScvO(2) and base deficit were found to be the best discriminators between survivors and nonsurvivors as assessed via receiver operator characteristic curve analysis. CONCLUSION Our study suggests that ScvO(2) and base deficit are useful in predicting the prognosis of dogs with severe sepsis and septic shock; animals with a higher ScvO(2) and lower base deficit at admission to the ICU have a lower probability of death.
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Affiliation(s)
- Andreza Conti-Patara
- Department of Veterinary Surgery, School of Veterinary Medicine and Zootechnics, University of São Paulo, São Paulo, SP, Brazil
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Mehta NM, Costello JM, Bechard LJ, Johnson VM, Zurakowski D, McGowan FX, Laussen PC, Duggan CP. Resting energy expenditure after Fontan surgery in children with single-ventricle heart defects. JPEN J Parenter Enteral Nutr 2012; 36:685-92. [PMID: 22539159 DOI: 10.1177/0148607112445581] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Data on resting energy expenditure (REE) and oxygen consumption (VO(2)) after pediatric cardiopulmonary bypass (CPB) will facilitate optimal nutrient prescription. METHODS The authors measured continuous REE and VO(2), using an in-line indirect calorimetery (IC) in 30 consecutive children with single-ventricle physiology immediately after Fontan surgery. REE during steady state at 8 hours after surgery was compared with standard equation-estimated energy expenditure (EEE). Patients were classified into 3 groups: hypermetabolic (measured REE [MREE]/EEE ratio >1.2), hypometabolic (MREE/EEE ratio <0.8), and normometabolic (MREE/EEE ratio 0.8-1.2). Demographic, anthropometric, and perioperative clinical characteristics were examined for their correlation with metabolic status. RESULTS In 26 of 30 patients with completed IC, mean REE at 8 hours after surgery was 57 ± 20 kcal/kg/d, and mean VO(2) was 110 ± 35 mL/min. Mean values of VO(2) and REE did not change within the first 24 hours after surgery. There was poor correlation between MREE at 8 hours and the EEE using the World Health Organization equation (r = 0.32, P = .11). Most patients (n = 19, 73%) were either normometabolic or hypometabolic. Lack of hypermetabolism was significantly associated with higher intraoperative serum lactate level and positive fluid balance compared with the rest of the group. CONCLUSIONS The authors report a low prevalence of hypermetabolism in children with single-ventricle defects after Fontan surgery. Measured REE had poor correlation with equation-estimated energy expenditure in a majority of the cohort. The absence of increased energy expenditure after CPB will influence energy prescription in this group.
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Affiliation(s)
- Nilesh M Mehta
- Division of Critical Care Medicine/Anesthesia, Department of Anesthesiology, Pain and Perioperative Medicine, Children's Hospital Boston, Harvard Medical School, Bader 634, MSICU Office, 300 Longwood Ave, Boston, MA 02115, USA.
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Li J. Systemic oxygen transport derived by using continuous measured oxygen consumption after the Norwood procedure-an interim review. Interact Cardiovasc Thorac Surg 2012; 15:93-101. [PMID: 22457186 DOI: 10.1093/icvts/ivs089] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The balance between systemic O(2)consumption (VO(2)) and O(2)delivery (DO(2)) is impaired in children after cardiopulmonary bypass surgery, with decreased DO(2)and increased VO(2). The major goal, and the major challenge, of postoperative management has been to match DO(2)to VO(2)in order to sustain cellular metabolism, particularly in neonates after the Norwood procedure. While much effort has been put into augmenting cardiac output and DO(2), VO(2)remains largely ignored. Respiratory mass spectrometry allows the precise and continuous measurement of VO(2). Measured VO(2), using the direct Fick principle, allows for the calculation of each element of systemic O(2)transport in the complex Norwood circulation. The actual measurements of O(2)transport have allowed us, in the past five years or so, to extensively investigate the Norwood physiology in terms of the VO(2)-DO(2)relationship and the factors affecting it in clinical treatments. Therefore, the first objective of this article is to introduce the technique of respiratory mass spectrometry and its adaption to measure VO(2)across paediatric ventilators with continuous flow. The second objective is to give an interim review of the main findings in our studies on systemic O(2)transport in 17 neonates in the first 72 h after the Norwood procedure. These findings include the profiles of systemic O(2)transport, the important contribution of VO(2)to the impaired balance of O(2)transport and the complex effects of some routine clinical treatments on the VO(2)-DO(2)relationship (including catecholamines, PaCO(2), Mg(2+)and hyperglycaemia, as well as patient-specific anatomical variations). The influence of systemic O(2)transport on cerebral oxygenation is also introduced. This information may help us to refine postoperative management in neonates after the Norwood procedure. Our initial studies mark the end of the beginning, but much is yet explored. Ultimately, the resultant improved systemic and regional O(2)transport in the early postoperative period may have an important impact on long-term outcomes, thereby improving the quality of life for these vulnerable children.
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Affiliation(s)
- Jia Li
- Department of Pediatrics, Division of Pediatric Cardiology, Stollery Children's Hospital, University of Alberta, Mazankowski Alberta Heart Institute, Edmonton, Canada.
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Loebe M, Locziewski S, Brunkhorst FM, Harke C, Hetzer R. Procalcitonin in patients undergoing cardiopulmonary bypass in open heart surgery-first results of the Procalcitonin in Heart Surgery study (ProHearts). Intensive Care Med 2009; 26 Suppl 2:S193-8. [PMID: 18470719 DOI: 10.1007/bf02900737] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To investigate procalcitonin (PCT) levels in patients undergoing cardiopulmonary bypass (CPB) in order to assess the prevalence and prognostic capacity of elevated PCT levels following CPB in open heart surgery. DESIGN prospective observational study in consecutive patients. SETTING Twenty-four-bed ICU, department of thoracic and cardiovascular surgery, university hospital. PATIENTS Seven hundred and twenty two patients, 691 of whom underwent CPB, i.e., 476 had coronary bypass surgery (CABG), 130 valve replacement, 34 combined CABG and valve replacement and 23 thoracic aortic surgery. INTERVENTIONS Standard perfusion techniques were used with cardioplegic arrest and mild hypothermia (28-32 degrees C). With the exception of thoracic aortic procedures, full-flow perfusion was performed. MEASUREMENTS AND RESULTS PCT was measured prior to surgery and daily thereafter until ICU discharge or death. PCT significantly increased at day 1 postoperatively compared to baseline values (0.25+/-1.65 vs 6.49+/-22.0 ng/ml, p<0.005). However, in 55.1% of patients PCT was below 1.0 ng/ml. In 12.8% of CABG patients PCT was increased to >5.0 ng/ml, compared to 39% in valve patients and 35% of patients with aortic surgery. An elevated PCT level >1.0-5.0 ng/ml at day 1 was highly predictive of mortality (P<0.03, vs<1.0 ng/ml), with an additional accuracy when levels >5.0 ng/ml were measured (P<0.002 vs<1.0 ng/ml). CONCLUSIONS These results provide evidence that PCT might serve as an early prognostic marker in patients undergoing CPB in open heart surgery. It may be worth considering immunomodulating approaches in patients presenting elevated PCT levels in the early phase after CPB.
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Affiliation(s)
- M Loebe
- Department of Thoracic and Cardiovascular Surgery, Deutsches Herzzentrum Berlin, Augustenburger Platz 1, D-13353 Berlin, Germany.
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Sun YJ, Chen WM, Zhang TZ, Cao HJ, Zhou J. Effects of cardiopulmonary bypass on tight junction protein expressions in intestinal mucosa of rats. World J Gastroenterol 2008; 14:5868-75. [PMID: 18855986 PMCID: PMC2751897 DOI: 10.3748/wjg.14.5868] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM: To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass (CPB) in rats.
METHODS: Thirty anesthetized rats were randomly divided into two groups: Group S (n = 10) served as sham operation and group C (n = 20) served as CPB which underwent CPB for 1 h. Expression of occludin and zonula occludens-1 (ZO-1) were determined by Western blotting and immunocytochemistry, respectively. Plasma levels of diamine oxidase (DAO) and d-lactate were determined using an enzymatic spectrophotometry.
RESULTS: Immunohistochemical localization of occludin and ZO-1 showed disruption of the tight junctions in enterocytes lining villi at the end of CPB and 2 h after CPB. The intensities of the occludin and ZO-1 at the end of CPB were lower than those of control group (76.4% ± 22.5% vs 96.5% ± 28.5% and 62.4% ± 10.1% vs 85.5% ± 25.6%, P < 0.05) and were further lower at 2 h after CPB (50.5% ± 10.5% and 45.3% ± 9.5%, P < 0.05). Plasma d-lactate and DAO levels increased significantly (8.688 ± 0.704 vs 5.745 ± 0.364 and 0.898 ± 0.062 vs 0.562 ± 0.035, P < 0.05) at the end of CPB compared with control group and were significantly higher at 2 h after CPB than those at the end of CPB (9.377 ± 0.769 and 1.038 ± 0.252, P < 0.05). There were significant negative correlations between occludin or ZO-1 expression and DAO (r2 = 0.5629, r2 = 0.5424, P < 0.05) or d-lactate levels (r2 = 0.6512, r2 = 0.7073, P < 0.05) both at the end of CPB and 2 h after CPB.
CONCLUSION: CPB markedly down-regulates the expression of occludin and ZO-1 proteins in intestinal mucosa of rats. The close correlation between expression of tight junctions (TJs) and plasma levels of DAO or d-lactate supports the hypothesis that intestinal permeability increases during and after CPB because of decreases in the expressions of TJs.
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Yazigi A, El Khoury C, Jebara S, Haddad F, Hayeck G, Sleilaty G. Comparison of Central Venous to Mixed Venous Oxygen Saturation in Patients With Low Cardiac Index and Filling Pressures After Coronary Artery Surgery. J Cardiothorac Vasc Anesth 2008; 22:77-83. [DOI: 10.1053/j.jvca.2007.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2006] [Indexed: 11/11/2022]
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Li J, Zhang G, McCrindle BW, Holtby H, Humpl T, Cai S, Caldarone CA, Redington AN, Van Arsdell GS. Profiles of hemodynamics and oxygen transport derived by using continuous measured oxygen consumption after the Norwood procedure. J Thorac Cardiovasc Surg 2007; 133:441-8. [PMID: 17258581 DOI: 10.1016/j.jtcvs.2006.09.033] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 08/11/2006] [Accepted: 09/06/2006] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The lack of accurate measurement of hemodynamics and oxygen transport has limited our understanding of Norwood physiology and postoperative management. We used measured oxygen consumption to characterize hemodynamics and oxygen transport after the classic Norwood procedure. METHODS Fourteen neonates had continuous respiratory mass spectrometry to measure oxygen consumption (VO2). Arterial, superior vena caval, and pulmonary venous saturations were measured at 2- to 4-hour intervals for 72 hours postoperatively. Systemic (Qs) and pulmonary (Qp) blood flows, systemic vascular resistance (SVR) and pulmonary vascular resistance inclusive of the Blalock-Taussig shunt (BT-PVR), systemic oxygen delivery (DO2), and the oxygen extraction ratio (ERO2) were calculated. RESULTS Qs and DO2 were low during the first 12 hours (1.8 +/- 0.6 L x min(-1) x m(-2) and 281 +/- 86 mL x min(-1) x m(-2) at the 12th hour, respectively) and increased over the study period (P < .05 for both). VO2 decreased markedly during the first 24 hours (101 +/- 26 to 86 +/- 16 mL x min(-1) x m(-2), P < .0001). Consequently, ERO2 decreased significantly over the study, most rapidly during the first 24 hours (0.44 +/- 0.11 to 0.28 +/- 0.09, P < .0001). There was a close correlation of DO2 to SVR and to Qs (P < .0001 for both). There was no correlation of DO2 to BT-PVR (P = .14) or to Qp (P = .67). DO2 was closely correlated with hemoglobin value (P < .0001), weakly correlated with PaO2 (P = .0002), and not correlated with arterial oxygen saturation (P = .32). CONCLUSIONS There is wide variability of hemodynamics and oxygen transport after the Norwood procedure. The decrease in VO2 during the first 24 hours is the main contributor to improving the balance of oxygen transport. DO2 is most closely correlated to SVR and hemoglobin and weakly correlated to PaO2. It is not correlated to Qp. Postoperative management strategies to decrease VO2 and maintain a high hemoglobin level and a low SVR appear to be rational.
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Affiliation(s)
- Jia Li
- Cardiac Program, the Hospital for Sick Children, Toronto, Ontario, Canada
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Li J, Zhang G, Holtby H, Humpl T, Caldarone CA, Van Arsdell GS, Redington AN. Adverse Effects of Dopamine on Systemic Hemodynamic Status and Oxygen Transport in Neonates After the Norwood Procedure. J Am Coll Cardiol 2006; 48:1859-64. [PMID: 17084263 DOI: 10.1016/j.jacc.2006.07.038] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Revised: 06/26/2006] [Accepted: 07/10/2006] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The purpose of this study was to evaluate the effects of dopamine on hemodynamic status and oxygen transport in neonates after the Norwood procedure. BACKGROUND Dopamine is widely used to augment cardiac performance and increase oxygen delivery (DO2) in patients after cardiopulmonary bypass (CPB). This might be at the expense of increased myocardial and systemic oxygen consumption (VO2), thus offsetting the improved DO2. This balance is particularly fragile in critically ill neonates. METHODS Systemic oxygen consumption was continuously measured with respiratory mass spectrometry in 13 sedated, paralyzed, and mechanically ventilated neonates for 72 h after the Norwood procedure. Arterial, superior vena caval, and pulmonary venous blood gases were measured to calculate pulmonary blood flow (Q(p)) and systemic blood flow (Q(s)), DO2, and oxygen extraction ratio (ERO2). Rate-pressure product was calculated. Dopamine at a dose of 5 microg/kg/min was routinely administered at cessation of CPB and terminated within the first 48 h. Hemodynamic and oxygen transport measures were obtained before and at 100 min after the termination of dopamine. RESULTS Terminating dopamine was not associated with significant changes in arterial pressure, Q(p), Q(s), or DO2 but was associated with a significant decrease in heart rate (p = 0.003), rate-pressure product (p = 0.03), and VO2 (-20 +/- 11%, p < 0.0001), resulting in a significant decrease in ERO2 (p = 0.01). CONCLUSIONS Dopamine induces a significant increase in VO2 in neonates after the Norwood procedure, and termination is associated with an improved balance of VO2-DO2. These data further emphasize the importance of understanding changes in VO2 as well as DO2 in infants after cardiac surgery.
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Affiliation(s)
- Jia Li
- Cardiac Program, the Hospital for Sick Children, Toronto, Ontario, Canada
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Allen ML, Hoschtitzky JA, Peters MJ, Elliott M, Goldman A, James I, Klein NJ. Interleukin-10 and its role in clinical immunoparalysis following pediatric cardiac surgery. Crit Care Med 2006; 34:2658-65. [PMID: 16932228 DOI: 10.1097/01.ccm.0000240243.28129.36] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE A systemic insult is associated with subsequent hyporesponsiveness to endotoxin (as measured by ex vivo tumor necrosis factor [TNF]-alpha production) and an increased risk of late nosocomial infection in some patients. When combined with low monocyte surface major histocompatibility complex class II expression, this state of altered host defense is now commonly referred to as immunoparalysis. This study was undertaken to delineate the relationship between observed levels of the anti-inflammatory cytokine interleukin-10, common genetic polymorphisms that influence these levels, and the occurrence and severity of endotoxin hyporesponsiveness in children following elective cardiac surgery requiring cardiopulmonary bypass. DESIGN A prospective observational clinical study. SETTING A tertiary pediatric cardiac center. PATIENTS Thirty-six infants and children <2 yrs of age undergoing elective cardiac surgery requiring cardiopulmonary bypass. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS We investigated the production of TNF-alpha, interleukin-6, interleukin-8, interleukin-1 receptor antagonist, and interleukin-10 in whole blood in response to lipopolysaccharide (Neisseria meningitides 10 ng/mL) in samples drawn before, during, and up to 48 hrs after surgery. Patients were genotyped for the -1082, -819, and -592 interleukin-10 promoter polymorphisms. Whole blood cytokine response to lipopolysaccharide was reduced postoperatively to </=50% of preoperative levels for all cytokines measured. Stimulated cytokine production was lowest in cases with the highest postoperative plasma interleukin-10 levels, which were in turn associated with the GCC haplotype. Those patients in whom the whole blood response to endotoxin was maintained (TNF-alpha >100 pg/mL) over the first 48 hrs were more likely to have an uncomplicated short stay (odds ratio 4.7, 95% confidence interval 1-22). CONCLUSIONS Immediately following cardiac surgery, many children become relatively refractory to lipopolysaccharide stimulation. This immunoparalysis appears to be related in part to high circulating levels of interleukin-10 and places these patients at increased risk of postoperative complications. Interleukin-10 genotype may be a risk factor for immunoparalysis.
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Affiliation(s)
- Meredith L Allen
- Critical Care Group-Portex Unit, Institute of Child Health, University College London, UK
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Abstract
“All the vital mechanisms, however varied they may be, have only one object, that of preserving constant the conditions of life in the internal environment.”1An essential function of the cardiopulmonary system is to generate sufficient flow of oxygenated blood around the circulation in order to maintain normal cellular metabolism. The systemic delivery of oxygen is a function of the cardiac output and the content of oxygen in the systemic arterial blood, while the extent to which metabolising tissues require this oxygen for the maintenance of their integrity and function defines the systemic consumption of oxygen. As metabolising tissues have no mechanism for storing oxygen, they depend on its continuous supply, which must at least match their changing demands. As a result, it is a fundamental requirement of survival that the systemic consumption of oxygen, at all times, is matched by appropriate levels of its delivery.
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Affiliation(s)
- Daniel J Penny
- The Department of Cardiology, The Royal Children's Hospital, The Murdoch Children's Research Institute, Australia.
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Nguyen HB, Rivers EP, Abrahamian FM, Moran GJ, Abraham E, Trzeciak S, Huang DT, Osborn T, Stevens D, Talan DA. Severe sepsis and septic shock: review of the literature and emergency department management guidelines. Ann Emerg Med 2006; 48:28-54. [PMID: 16781920 DOI: 10.1016/j.annemergmed.2006.02.015] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Revised: 01/20/2006] [Accepted: 02/14/2006] [Indexed: 01/09/2023]
Abstract
Severe sepsis and septic shock are as common and lethal as other acute life-threatening conditions that emergency physicians routinely confront such as acute myocardial infarction, stroke, and trauma. Recent studies have led to a better understanding of the pathogenic mechanisms and the development of new or newly applied therapies. These therapies place early and aggressive management of severe sepsis and septic shock as integral to improving outcome. This independent review of the literature examines the recent pathogenic, diagnostic, and therapeutic advances in severe sepsis and septic shock for adults, with particular relevance to emergency practice. Recommendations are provided for therapies that have been shown to improve outcomes, including early goal-directed therapy, early and appropriate antimicrobials, source control, recombinant human activated protein C, corticosteroids, and low tidal volume mechanical ventilation.
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Li J, Zhang G, Holtby HM, McCrindle BW, Cai S, Humpl T, Caldarone CA, Williams WG, Redington AN, Van Arsdell GS. Inclusion of oxygen consumption improves the accuracy of arterial and venous oxygen saturation interpretation after the Norwood procedure. J Thorac Cardiovasc Surg 2006; 131:1099-107. [PMID: 16678596 DOI: 10.1016/j.jtcvs.2005.10.057] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 10/05/2005] [Accepted: 10/10/2005] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Management strategy for the postoperative Norwood neonate has been formulated from models that have estimated oxygen consumption (VO2). Superior vena caval oxygen saturation (SVO2), systemic arterial and superior vena caval oxygen saturation difference (Sa-VO2), and oxygen excess factor (Omega = arterial oxygen saturation/Sa-VO2) have been used as indirect indicators to estimate systemic blood flow (Qs) and oxygen delivery (DO2). We sought to examine the correlation of the indirect indicators to VO2-derived measures of oxygen transport. METHODS Respiratory mass spectrometry was used to continuously measure VO2 after the Norwood procedure (n = 13). Measured saturations and the direct Fick equation were used to obtain pulmonary blood flow, Qs, DO2, and oxygen extraction ratio (ERO2) values. Correlations to SVO2, Sa-VO2, and Omega were sought. RESULTS There was a close correlation of SVO2, Sa-VO2, and Omega to ERO2 (r = 0.92, 0.96, and 0.97, respectively; P < .0001). Correlation to Qs and DO2 was variable (r = 0.39 to 0.78, respectively; P < .0001). Correlation to VO2 was poor but significant (r = 0.24 to 0.40, P < .0001). Inclusion of VO2 improved the correlation to Qs and DO2 (r = 0.66 to 0.97, P < .0001). CONCLUSIONS The close correlation of SVO2, Sa-VO2, and Omega to ERO2 indicates that each is a measure of the balance of DO2 and extraction. The significant but less reliable correlation to DO2 and VO2 indicates the values for SVO2, Sa-VO2, and Omega do not discriminate between the contribution of DO2 and VO2. Measured VO2 and hemodynamics may improve the optimization of postoperative management strategy in the individual neonate.
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Affiliation(s)
- Jia Li
- Cardiac Program, the Hospital for Sick Children, Toronto, Ontario, Canada
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Li J, Hoschtitzky A, Allen ML, Elliott MJ, Redington AN. An analysis of oxygen consumption and oxygen delivery in euthermic infants after cardiopulmonary bypass with modified ultrafiltration. Ann Thorac Surg 2005; 78:1389-96. [PMID: 15464503 DOI: 10.1016/j.athoracsur.2004.02.032] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/10/2004] [Indexed: 11/25/2022]
Abstract
BACKGROUND The balance between systemic oxygen consumption (VO2) and delivery (DO2) is impaired after cardiopulmonary bypass (CPB) and is related to systemic inflammatory response syndrome. We sought to assess VO2 and DO2 and their relationship with proinflammatory cytokines after CPB with the use of modified ultrafiltration (MUF) in infants. METHODS Sixteen infants, aged 1-11.5 months (median, 6.3 months), undergoing hypothermic CPB with MUF were studied during the first 12 hours after arrival in the intensive care unit (ICU). The central temperature was maintained at 36.8-37.1 degrees C using external cooling or warming. VO2 was continuously measured using respiratory mass spectrometry. Arterial blood samples for the tumor necrosis factor (TNF), interleukin-6 (IL-6), and interleukin-8 (IL-8) were taken and DO2 was calculated using the Fick principle on arrival at the ICU, and 2, 4, 8, and 12 hours postoperatively. Cytokines were additionally measured after induction of anesthesia and at the end of MUF. RESULTS VO2 significantly decreased by 18.8% during the study period. DO2 was depressed throughout this period and reached a nadir at 8 hours (357.1 +/- 136.2 ml x min(-1) x m(-2)). The decrease in cytokines was accompanied with the decrease in VO2 despite varied relationships between the levels of each of the cytokines and VO2 measurements. CONCLUSIONS Our data indicate an unusual continuous decrease in VO2 during the first 12 hours after CPB in infants. Control of body temperature to maintain euthermia in addition to the use of MUF may be beneficial to the balance between VO2 and DO2 in the early postoperative period.
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Affiliation(s)
- Jia Li
- Division of Cardiology, Hospital for Sick Children, Toronto, Ontario, Canada
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Bracht H, Takala J, Tenhunen JJ, Brander L, Knuesel R, Merasto-Minkkinen M, Jakob SM. Hepatosplanchnic blood flow control and oxygen extraction are modified by the underlying mechanism of impaired perfusion. Crit Care Med 2005; 33:645-53. [PMID: 15753759 DOI: 10.1097/01.ccm.0000156445.59009.49] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the effects of low hepatosplanchnic blood flow on regional blood flow control and oxygenation. DESIGN Three randomized, controlled animal experiments. SETTING Two university experimental research laboratories. SUBJECTS Pigs of either gender. INTERVENTIONS Isolated abdominal blood flow reduction: An extracorporeal shunt with reservoir and roller pump was inserted between proximal and distal aorta in 11 pigs. Abdominal aortic blood flow was reduced by 50% by activating the shunt. Mesenteric ischemia: In seven pigs, superior mesenteric arterial flow was reduced to 4 mL.kg.min for 4 hrs. Cardiac tamponade: In 12 pigs, aortic blood flow was reduced by cardiac tamponade to 50 mL (moderate tamponade) and further to 30 mL.kg.min (severe tamponade) for 1 hr each. In each experimental condition, the same number of control animals was used. MEASUREMENTS AND MAIN RESULTS Abdominal blood flow reduction, acute mesenteric ischemia, and moderate tamponade resulted in a portal venous flow (QPV) reduction to 51 +/- 23%, 52 +/- 18%, and 61 +/- 25% (mean +/- sd) of baseline flow, respectively. During abdominal blood flow reduction, QPV and hepatic arterial flow (QHA) decreased proportionally, whereas in moderate tamponade and acute mesenteric ischemia QPV reduction was associated with an increase in QHA of 30 +/- 39% and 102 +/- 108%, respectively (p = .001 and .018). Prolonged mesenteric ischemia restored total hepatic blood flow (Qliver) completely. During all conditions, decreasing mesenteric oxygen consumption was partly prevented by increased mesenteric oxygen extraction (p < .001 for all conditions). In contrast, decreasing hepatic oxygen delivery was associated with increased oxygen extraction in tamponade (p = .009) but not in abdominal blood flow reduction. CONCLUSIONS Blood flow redistribution can restore Qliver totally when mesenteric blood flow is reduced selectively, partially when cardiac output is reduced, and not at all during abdominal blood flow reduction. Since hepatic oxygen extraction does not increase in abdominal blood flow reduction, hepatic oxygenation is at risk in this condition.
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Affiliation(s)
- Hendrik Bracht
- Department of Intensive Care Medicine, University Hospital Bern, Switzerland
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19
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Abstract
Gastrointestinal complications occur in about 2.5% of patients undergoing cardiac surgery, are associated with a high mortality (about 33%), and account for nearly 15% (and perhaps increasing) of all postoperative deaths. The various complications and risk factors are reviewed. Splanchnic ischemia prior to, during, and especially postoperatively appears to be an important cause of these complications. In addition, splanchnic ischemia is hypothesized to be one cause of the systemic inflammatory response syndrome and multiorgan failure that may follow cardiac surgery. The physiology of splanchic perfusion and the effects of cardiac surgery, including cardiopulmonary bypass, on it are reviewed. Finally, possible methods to minimize splanchnic ischemia and reduce the incidence of abdominal complications are discussed.
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Affiliation(s)
- Eugene A Hessel
- University of Kentucky College of Medicine, Lexington, Kentucky, USA.
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Liaudet L. Poly(adenosine diphosphate-ribose) polymerase: A novel actor in mesenteric complications of cardiopulmonary bypass. Crit Care Med 2004; 32:2543-4. [PMID: 15599165 DOI: 10.1097/01.ccm.0000148092.47239.1a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Li J, Stenbøg E, Bush A, Grøfte T, Redington AN, Penny DJ. Insulin-like growth factor 1 improves the relationship between systemic oxygen consumption and delivery in piglets after cardiopulmonary bypass. J Thorac Cardiovasc Surg 2004; 127:1436-41. [PMID: 15116005 DOI: 10.1016/j.jtcvs.2003.08.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE We sought to assess the effects of insulin-like growth factor 1 on the balance between systemic oxygen consumption and oxygen delivery after cardiopulmonary bypass in piglets. METHODS Twelve piglets weighing 4.5 to 8.3 kg undergoing hypothermic (28 degrees C) cardiopulmonary bypass for 70 to 120 minutes with 40 minutes of aortic crossclamping were studied before and during the first 6 hours after cardiopulmonary bypass. Oxygen consumption was continuously measured by an indirect calorimeter, Deltatrac II MBM-200 Metabolic Monitor (Datex Division Instrumentarium, Helsinki, Finland). Oxygen delivery and cardiac output were calculated from oxygen consumption and the arterial and mixed venous oxygen contents sampled before and every 30 minutes after cardiopulmonary bypass. Oxygen extraction ratio was derived by the ratio of oxygen consumption to oxygen delivery. Arterial blood lactate was measured before and every 30 minutes after cardiopulmonary bypass. Six animals were randomly assigned to receive an intravenous infusion of insulinlike growth factor 1 at 1.2 mg/h from 1 to 6 hours after cardiopulmonary bypass; the remaining 6 served as a control group. RESULTS Relative to the control group, intravenous infusion of insulin-like growth factor 1 significantly reduced oxygen consumption (P =.02) and increased cardiac output (P =.016) and oxygen delivery (P =.049) during the first 6 hours after surgery with hypothermic cardiopulmonary bypass. As a result, oxygen extraction was significantly decreased (P =.012). CONCLUSIONS Intravenous infusion of insulin-like growth factor 1 improved oxygen transport by reducing oxygen consumption as well as increasing cardiac output and oxygen delivery during the first 6 hours after cardiopulmonary bypass in piglets. This may have important clinical implications for the care of critically ill children after surgery with cardiopulmonary bypass.
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Affiliation(s)
- Jia Li
- Division of Cardiology, Hospital for Sick Children, Toronto, Ontario, Canada
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22
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Schippers EF, van 't Veer C, van Voorden S, Martina CAE, le Cessie S, van Dissel JT. TNF-α promoter, Nod2 and toll-like receptor-4 polymorphisms and the in vivo and ex vivo response to endotoxin. Cytokine 2004; 26:16-24. [PMID: 15016407 DOI: 10.1016/j.cyto.2003.12.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2003] [Revised: 11/07/2003] [Accepted: 12/08/2003] [Indexed: 11/22/2022]
Abstract
Humans exhibit substantial inter-individual differences in TNF-alpha production upon endotoxin stimulation. To determine to what extent the lipopolysaccharide-induced TNF-alpha production capacity in vivo and ex vivo is determined by polymorphisms in toll-like receptor-4 (TLR4), the TNF-alpha promoter region and Nod2, we screened for two TLR4 polymorphisms, a Nod2 polymorphism and the TNF-alpha promoter polymorphisms. We measured the perioperative endotoxemia and TNF-alpha production and the TNF-alpha production capacity of each patient in a whole-blood stimulation assay using blood drawn before anesthesia, using various LPS concentrations, in patients undergoing elective cardiac surgery. This operation represents a major surgical trauma associated with ischemia-reperfusion injury and triggers an endotoxemia and profound inflammatory response. In vivo TNF-alpha production was positively correlated with the level of endotoxemia after aortic declamping; thus TNF-alpha levels were higher in patients having endotoxemia compared to patients without endotoxemia. This correlation was observed in patients with any of the genotypes studied, and did not differ between the various genotypes. In vivo TNF-alpha levels correlated best with those ex vivo after stimulation with 1000 ng/mL LPS, and the estimated maximal TNF-alpha release capacity. Subjects with the wild-type TLR4 gene had similar levels of TNF-alpha upon LPS stimulation ex vivo as compared with patients carrying Asp299Gly and/or the Thr399Ile TLR4 polymorphism. Our results indicate that polymorphisms in the TLR4 receptor, Nod2 and TNF-alpha promoter region are not strongly associated with in vivo and ex vivo TNF-alpha production capacity upon endotoxin stimulation. This suggests that in this model of natural LPS release, the variation between individuals in TNF-alpha release can only modestly be determined by genetic background (TNF-alpha promoter, Nod2 and TLR4) of the individual.
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Affiliation(s)
- Emile F Schippers
- Department of Infectious Diseases, C5-P42, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
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Walsh TS. Recent advances in gas exchange measurement in intensive care patients. Br J Anaesth 2003; 91:120-31. [PMID: 12821571 DOI: 10.1093/bja/aeg128] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- T S Walsh
- Royal Infirmary, Edinburgh EH3 9YW, UK.
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Li J, Bush A, Schulze-Neick I, Penny DJ, Redington AN, Shekerdemian LS. Measured versus estimated oxygen consumption in ventilated patients with congenital heart disease: the validity of predictive equations. Crit Care Med 2003; 31:1235-40. [PMID: 12682498 DOI: 10.1097/01.ccm.0000060010.81321.45] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the validity of predictive equations in calculating oxygen consumption (Vo(2)) in ventilated patients with congenital heart disease. DESIGN Prospective study. SETTING Cardiac catheterization laboratories and intensive care units of two university teaching hospitals. PATIENTS A total of 126 patients with congenital heart disease were studied. Of these, 75 patients received anesthesia in the pediatric cardiac catheterization laboratory, and 51 were deeply sedated in the intensive care unit after open heart surgery. MEASUREMENTS AND MAIN RESULTS Vo(2) was measured directly in all patients using respiratory mass spectrometry. Estimated values for absolute Vo(2) (mL/min) and indexed Vo(2) (mL.min-1.m-2) were calculated from the four predictive equations published by LaFarge and Miettinen, Lundell et al., Wessel et al., and Lindahl. The agreement between measured and estimated Vo(2) was evaluated by calculating their bias and limits of agreement. A failure of agreement between measured and estimated Vo(2) was noted in both groups of patients, irrespective the equation used, and the agreement was poorer in patients in the intensive care unit. The equation by LaFarge and Miettinen produced the closest estimation in patients at cardiac catheterization with a bias of 4.5 mL/min for absolute Vo(2) and 6.9 mL.min-1.m-2 for indexed Vo(2). A systematic error of overestimating lower and underestimating higher indexed Vo(2) mL.min-1.m-2 was introduced in both groups. CONCLUSION Predictive equations do not accurately estimate Vo(2) in ventilated patients with congenital heart disease.
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Affiliation(s)
- Jia Li
- Department of Cardiology, Great Ormond Street Hospital, London, UK
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Dixon B, Santamaria JD, Campbell DJ. Plasminogen activator inhibitor activity is associated with raised lactate levels after cardiac surgery with cardiopulmonary bypass. Crit Care Med 2003; 31:1053-9. [PMID: 12682472 DOI: 10.1097/01.ccm.0000055390.97331.db] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the pathophysiology underlying raised lactate levels after cardiac surgery with cardiopulmonary bypass (CPB). DESIGN Prospective observational study. SETTING Medical and surgical intensive care unit of a tertiary hospital. PATIENTS A total of 40 patients undergoing first-time coronary artery bypass grafting with CPB. INTERVENTIONS The prothrombotic response to cardiac surgery with CPB was assessed by measuring plasma levels of prothrombin fragment 1 + 2 and plasminogen activator inhibitor (PAI) activity. The hemodynamic responses to cardiac surgery with CPB were also measured using standard techniques. MEASUREMENTS AND MAIN RESULTS After cardiac surgery, prothrombin fragment 1 + 2 levels increased 6-fold and PAI activity increase 2- to 3-fold (p <.0001). Lactate levels were not associated with prothrombin fragment 1 + 2 and PAI activity levels after CPB. Lactate levels were associated with baseline PAI activity (p =.006), a history of hypertension (p =.02), raised baseline lactate levels (p =.02), an early increase in body temperature after CPB (p =.05), a late increase in oxygen consumption after CPB (p =.03), and a raised white cell count after CPB (p =.06). Lactate levels were inversely associated with the maximum activated clotting time level reached during CPB (p =.02). Multivariate linear regression demonstrated lactate levels were independently associated with baseline PAI activity. CONCLUSION We found cardiac surgery with CPB was associated with a marked prothrombotic response. Lactate levels were associated with elevated baseline PAI activity and evidence of an amplified inflammatory response to cardiac surgery with CPB. Our findings implicate aspects of the inflammatory response, including microvascular thrombosis, in the development of raised lactate levels after cardiac surgery with CPB.
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Affiliation(s)
- Barry Dixon
- Intensive Care Centre, St. Vincent's Hospital, St. Vincent's Institute of Medical Research, Fitzroy, Australia
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Sason-Ton Y, Ben Abraham R, Lotan D, Dagan O, Prince T, Barzilay Z, Paret G. Tumor necrosis factor and clinical and metabolic courses after cardiac surgery in children. J Thorac Cardiovasc Surg 2002; 124:991-8. [PMID: 12407384 DOI: 10.1067/mtc.2002.124391] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE This study was undertaken to determine the relationship between plasma tumor necrosis factor concentrations and hemodynamic and metabolic parameters during the postoperative clinical course in children undergoing cardiac surgery. METHODS Tumor necrosis factor levels of 10 consecutive children undergoing surgery for repair of congenital heart defects were analyzed in blood samples drawn at predetermined time points during surgery and up to 24 hours thereafter. Clinical data were collected at these times for correlation to tumor necrosis factor levels. RESULTS All the patients survived. Tumor necrosis factor was detected in all 10 children. Tumor necrosis factor levels declined after induction of general anesthesia (201 +/- 65 pg/mL) steadily decreasing during surgery, reaching 80 +/- 50 pg/mL at 24 hours after the operation. Tumor necrosis factor levels were found to be inversely correlated with mean blood pressure values and indicators of acidosis (bicarbonate levels and base excess, P <.03). They were not correlated with the durations of cardiopulmonary bypass and aortic crossclamping. CONCLUSIONS Tumor necrosis factor released into the circulation during and after pediatric cardiac surgery under cardiopulmonary bypass may be related to the hemodynamic and acid-base changes observed after cardiac surgery. Elucidation of the relationship between tumor necrosis factor and patient outcome in high-risk patients awaits further studies.
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Affiliation(s)
- Yokrat Sason-Ton
- Department of Pediatric Intensive Care, Chaim Sheba Medical Center, Tel Hashomer, Israel
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Bouter H, Schippers EF, Luelmo SAC, Versteegh MIM, Ros P, Guiot HFL, Frölich M, van Dissel JT. No effect of preoperative selective gut decontamination on endotoxemia and cytokine activation during cardiopulmonary bypass: a randomized, placebo-controlled study. Crit Care Med 2002; 30:38-43. [PMID: 11905407 DOI: 10.1097/00003246-200201000-00006] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Cardiopulmonary bypass predisposes the splanchnic region to inadequate perfusion and increases in gut permeability. Related to these changes, circulating endotoxin has been shown to rise during cardiac surgery, and may contribute to cytokine activation, high oxygen consumption, and fever ("postperfusion syndrome"). To a large extent, free endotoxin in the gut is a product of the proliferation of aerobic gram-negative bacteria and may be reduced by nonabsorbable antibiotics. OBJECTIVE To evaluate the effect of preoperative selective gut decontamination (SGD) on the incidence of endotoxemia and cytokine activation in patients undergoing open heart surgery. DESIGN Prospective, randomized, placebo-controlled double-blind trial. SETTING Tertiary-care university teaching hospital. INTERVENTION Preoperative administration for 5 to 7 days of oral nonabsorbable antibiotics (polymyxin B and neomycin) vs. placebo. The efficacy of SGD was assessed by culture of rectal swabs. PATIENTS Forty-four patients (median age 65 yrs, 29 males) were included in a pilot study to establish the sampling points of perioperative measurements. Seventy-eight consecutive patients (median age 65 yrs, 55 males) were enrolled for the prospective study; of these, 51 were randomly allocated to take SGD (n = 24) or placebo (n = 27); 27 were included in a control group (no medication). MEASUREMENTS AND RESULTS SGD but not placebo effectively reduced the number of rectal swabs that grew aerobic gram-negative bacteria (27% vs. 93%, respectively; p < .001). SGD did not affect the occurrence of perioperative endotoxemia, nor did it reduce the tumor necrosis factor-alpha, interleukin-10, or interleukin-6 concentrations (p > .20), as determined before surgery, upon aorta declamping, 30 mins into reperfusion, or 2 hrs after surgery. Also, SGD did not alter the incidence of postoperative fever or clinical outcome measures such as duration of artificial ventilation and intensive care unit and hospital stay. CONCLUSION SGD effectively reduces the aerobic gram-negative bowel flora in cardiac surgery patients but fails to affect the incidence of perioperative endotoxemia and cytokine activation during cardiopulmonary bypass and the occurrence of a postperfusion syndrome.
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Affiliation(s)
- Hens Bouter
- Department of Infectious Diseases, Leiden University Medical Center, The Netherlands
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Yamaura K, Okamoto H, Akiyoshi K, Irita K, Taniyama T, Takahashi S. Effect of low-dose milrinone on gastric intramucosal pH and systemic inflammation after hypothermic cardiopulmonary bypass. J Cardiothorac Vasc Anesth 2001; 15:197-203. [PMID: 11312479 DOI: 10.1053/jcan.2001.21954] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate the usefulness of low-dose milrinone on gastric intramucosal pH (pHi) and systemic inflammation in patients undergoing hypothermic cardiopulmonary bypass (CPB). DESIGN Prospective randomized study. SETTING University hospital. PARTICIPANTS Twenty patients scheduled for cardiac surgery. INTERVENTIONS Ten patients were administered a low dose of milrinone, 0.25 microg/kg/min, from the initiation of CPB to 1 hour after admission to the intensive care unit. The other patients were administered saline. Supplemental inotropes and intravenous fluid were given to obtain adequate mean arterial blood pressure and pulmonary artery occlusion pressure. MEASUREMENTS AND RESULTS Gastric pHi and carbon dioxide pressure (PCO2) were assessed by capnometric air tonometry. The difference between PCO2 and arterial carbon dioxide pressure (PaCO2), PCO2-gap, was also examined. Systemic inflammatory responses were evaluated by serum interleukin-6 and leukocyte counts. Hemodynamics, oxygen delivery index, and oxygen uptake index were monitored with catheters in the radial and pulmonary arteries (thermodilution). The hepatic venous blood flow and left ventricular flow were measured using transesophageal echocardiography. Milrinone prevented gastric intramucosal acidosis, detected as a decrease in pHi or an increase in PCO2-gap, without affecting hepatic venous blood flow. Increases in interleukin-6, leukocyte count, and oxygen uptake index, all of which developed after CPB, were significantly less in the milrinone group than in the control group. CONCLUSION These results suggest that in patients undergoing hypothermic CPB, supplemental low-dose milrinone prevents gastric intramucosal acidosis and increases in some markers of systemic inflammation.
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Affiliation(s)
- K Yamaura
- Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Bronicki RA, Backer CL, Baden HP, Mavroudis C, Crawford SE, Green TP. Dexamethasone reduces the inflammatory response to cardiopulmonary bypass in children. Ann Thorac Surg 2000; 69:1490-5. [PMID: 10881828 DOI: 10.1016/s0003-4975(00)01082-1] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND A randomized, prospective, double-blind study of 29 children was performed to evaluate the hypothesis that dexamethasone administration prior to cardiopulmonary bypass would decrease the inflammatory mediator release and improve the postoperative clinical course. METHODS Fifteen children received dexamethasone (1 mg/kg intravenously) and 14 (controls) received saline solution 1 hour prior to CPB. Serial blood analyses for interleukin-6, tumor necrosis factor-alpha, complement component C3a, and absolute neutrophil count were performed. Postoperative variables evaluated included temperature, supplemental fluids, alveolar-arterial oxygen gradient, and days of mechanical ventilation. RESULTS Dexamethasone caused an eightfold decrease in interleukin-6 levels and a greater than threefold decrease in tumor necrosis factor-alpha levels after CPB (p < 0.05). Complement component C3a and absolute neutrophil count were not affected by dexamethasone. The mean rectal temperature for the first 24 hours postoperatively was significantly lower in the group given dexamethasone than in the controls (37.2 degrees +/- 0.4 degrees C versus 37.7 degrees +/- 4 degrees C; p = 0.007). Dexamethasone-treated patients required less supplemental fluid during the first 48 hours (22 +/- 28 mL/kg versus 47 +/- 34 mL/kg; p = 0.04). Compared with controls, dexamethasone-treated children had significantly lower alveolar-arterial oxygen gradients during the first 24 hours (144 +/- 108 mm Hg versus 214 +/- 118 mm Hg; p = 0.02) and required less mechanical ventilation (median duration, 3 days versus 5 days; p = 0.02). CONCLUSIONS Dexamethasone administration prior to CPB in children leads to a reduction in the postbypass inflammatory response as assessed by cytokine levels and clinical course.
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Affiliation(s)
- R A Bronicki
- Department of Surgery, Northwestern University Medical School, Chicago, Illinois, USA
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Li J, Schulze-Neick I, Lincoln C, Shore D, Scallan M, Bush A, Redington AN, Penny DJ. Oxygen consumption after cardiopulmonary bypass surgery in children: determinants and implications. J Thorac Cardiovasc Surg 2000; 119:525-33. [PMID: 10694613 DOI: 10.1016/s0022-5223(00)70132-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE We sought to assess oxygen consumption and its determinants in children shortly after undergoing cardiopulmonary bypass operations. METHODS Twenty children, aged 2 months to 15 years (median, 3.75 years), undergoing hypothermic cardiopulmonary bypass operations were studied during the first 4 hours after arrival in the intensive care unit. Central and peripheral temperatures were monitored. Oxygen consumption was continuously measured by using respiratory mass spectrometry. Oxygen delivery was calculated from oxygen consumption and arterial and mixed venous oxygen contents, which were sampled every 30 minutes. Oxygen extraction was derived by the ratio of oxygen consumption and oxygen delivery. Arterial blood lactate levels were measured every 30 minutes. RESULTS There was a correlation between oxygen consumption and age in patients older than 3 months (r = -0.76). Mean oxygen consumption increased by 14.7% during the study. The increase in oxygen consumption was correlated with the increase in central temperature (r = 0.73). Nine patients had an arterial lactate level above 2 mmol/L on arrival. There were no significant differences in oxygen consumption, oxygen delivery, and oxygen extraction between the group with lactate levels between 2 and 3 mmol/L and the groups with normal lactate levels both on arrival and at 2 hours. One patient with a peak lactate level of 6.8 mmol/L had initially low oxygen delivery (241.3 mL. min(-1). m(-2)). CONCLUSIONS During the early hours after a pediatric cardiac operation, the increase in oxygen consumption is mainly attributed to the increase in central temperature. Oxygen consumption is negatively related to age. Mild lactatemia is common and does not appear to reflect oxygen delivery or oxygen consumption or a more complicated recovery.
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Affiliation(s)
- J Li
- Cardiothoracic Unit, Great Ormond Street Hospital for Children NHS Trust, London, UK
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Moriyama S, Okamoto K, Tabira Y, Kikuta K, Kukita I, Hamaguchi M, Kitamura N. Evaluation of oxygen consumption and resting energy expenditure in critically ill patients with systemic inflammatory response syndrome. Crit Care Med 1999; 27:2133-6. [PMID: 10548194 DOI: 10.1097/00003246-199910000-00009] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To determine whether oxygen consumption VO2), CO2 production, and resting energy expenditure (REE) in critically ill patients differ in varying grades of systemic inflammatory response syndrome (SIRS). DESIGN Prospective, clinical study. SETTING Intensive care unit at a university hospital. PATIENTS Twenty-six critically ill patients requiring mechanical ventilation. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS A total of 100 metabolic measurements were performed. The grade of SIRS and the Acute Physiology and Chronic Health Evaluation II score were evaluated at the time of the metabolic cart study. VO2 and REE differed among the groups inadequate for SIRS (non-SIRS), with SIRS without infection (nonseptic SIRS), and with SIRS with infection (septic SIRS) (125 +/- 37 mL/min/m2 and 855 +/- 204 kcal/day/m2, 135 +/- 33 mL/min/m2 and 948 +/- 214 kcal/day/m2, and 166 +/- 55 mL/min/m2 and 1149 +/- 339 kcal/day/m2, respectively; p < .005). Patients with septic SIRS had higher VO2 and REE than patients with non-SIRS and nonseptic SIRS. CONCLUSION VO2 and REE differ among groups of patients with non-SIRS, nonseptic SIRS, and septic SIRS. Patients with septic SIRS have higher VO2 and REE than patients with non-SIRS or nonseptic SIRS. The present study shows that classifying patients into three grades (non-SIRS, nonseptic SIRS, and septic SIRS) is a valid predictor of metabolic stress in critically ill patients.
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Affiliation(s)
- S Moriyama
- Division of Intensive and Critical Care Medicine, Kumamoto University School of Medicine, Kumamoto City, Japan
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Strüber M, Cremer JT, Gohrbandt B, Hagl C, Jankowski M, Völker B, Rückoldt H, Martin M, Haverich A. Human cytokine responses to coronary artery bypass grafting with and without cardiopulmonary bypass. Ann Thorac Surg 1999; 68:1330-5. [PMID: 10543502 DOI: 10.1016/s0003-4975(99)00729-8] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Coronary artery bypass grafting (CABG) is associated with a systemic inflammatory response. This has been attributed to cytokine release caused by extracorporeal circulation and myocardial ischemia. This study compares the inflammatory response after CABG with cardiopulmonary bypass and after minimally invasive direct coronary artery bypass grafting (MIDCABG) without cardiopulmonary bypass. METHODS Cytokine release and complement activation (interleukin-6 and interleukin-8, soluble tumor necrosis factor receptors 1 and 2, complement factor C3a, and C1 esterase inhibitor) were determined in 24 patients before and after CABG or MIDCABG. The maximum body temperature, chest drainage, and fluid balance were recorded for 24 hours after operation. RESULTS Release of interleukin-6, interleukin-8, and tumor necrosis factor receptors 1 and 2 was significantly higher (p < or = 0.005) in the CABG group than the MIDCABG group just after operation. After 24 hours, a significant increase in interleukin-6 was also found in the MIDCABG group (p = 0.001) compared with preoperative value. Body temperature and fluid balance were significantly higher after CABG (p < or = 0.001). CONCLUSIONS Minimally invasive direct coronary artery bypass grafting represents a less traumatizing technique of surgical revascularization. The reduction in the inflammatory response may be advantageous for patients with a high degree of comorbidity.
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Affiliation(s)
- M Strüber
- Department of Anesthesia, Hannover Medical School, Germany.
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Kristof AS, Magder S. Low systemic vascular resistance state in patients undergoing cardiopulmonary bypass. Crit Care Med 1999; 27:1121-7. [PMID: 10397216 DOI: 10.1097/00003246-199906000-00033] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the prevalence, hemodynamic characteristics, and risk factors for the low systemic vascular resistance (SVR) state in patients who have undergone cardiopulmonary bypass. DESIGN Prospective cohort study. SETTING The intensive care unit of a tertiary care hospital. PATIENTS Seventy-nine consecutive patients who underwent coronary artery bypass graft, mitral valve, or aortic valve procedures. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Low SVR was defined as an indexed systemic vascular resistance (SVRi) of <1800 dyne x sec/cm5 x m2 at two consecutive times postoperatively. SVRi, cardiac index, mean arterial pressure, temperature, and central venous pressure were recorded before bypass and at 0, 1, 2, 4, 8, and 16 hrs after bypass. We recorded age, gender, urgency of operation, use of angiotensin-converting enzyme inhibitors and calcium channel blockers, ejection fraction, pump time, cross-clamp time, use of antifibrinolytics, type of oxygenator, amrinone use, postoperative biochemical and hematologic values, medication use, fluid balance, intensive care unit admission duration, and hospital admission duration. We assessed the role of diabetes mellitus, current smoking, and systemic hypertension. The incidence of the low-SVR state was 35 of 79 patients during a 3-month period (44%). At 8 hrs postoperatively, the SVRi in low-SVR and non-low-SVR patients was 1594+/-50 (SEM) and 2103+/-56 (SEM) dyne x sec/cm5 x m2, respectively (p < .001). In low-SVR patients, there was an initial and sustained increase in cardiac index and central venous pressure that preceded the decrease in mean arterial pressure. The decrease in mean arterial pressure was maximal at 8 hrs postoperatively. Patients with low SVR were more likely to have longer cross-clamp times, to be male, and to have lower postoperative platelet counts (p < .05 for all). Low-SVR patients were less likely to require dobutamine in the first 4 hrs postoperatively. CONCLUSIONS Low SVR, a probable manifestation of systemic inflammatory response syndrome, is common in patients after cardiopulmonary bypass. These patients may respond better to a vasopressor to restore vascular tone than to volume loading to further increase cardiac index.
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Affiliation(s)
- A S Kristof
- Department of Medicine, McGill University, Royal Victoria Hospital, Montreal, Quebec, Canada
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Wan S, LeClerc JL, Huynh CH, Schmartz D, DeSmet JM, Yim AP, Vincent JL. Does steroid pretreatment increase endotoxin release during clinical cardiopulmonary bypass? J Thorac Cardiovasc Surg 1999; 117:1004-8. [PMID: 10220696 DOI: 10.1016/s0022-5223(99)70382-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The mechanism involved in the endotoxemia frequently recognized during cardiopulmonary bypass remains unclear. It has also been suggested that endotoxin levels were higher in steroid-pretreated patients undergoing cardiopulmonary bypass. METHODS Twenty patients undergoing cardiopulmonary bypass were randomly pretreated with steroids (methylprednisolone, 30 mg/kg) or placebo. Blood samples for endotoxin measurement were drawn simultaneously from the superior and inferior venae cavae before heparin administration, 5 and 50 minutes after the onset of bypass, 5 minutes after aortic declamping, at the end of bypass, and 1, 2, and 20 hours after the end of cardiopulmonary bypass. RESULTS The perioperative variables in the two groups were similar. Blood endotoxin levels were higher in the inferior vena cava than in the superior vena cava immediately after the onset of bypass. Endotoxin levels in inferior vena cava blood were significantly lower in steroid-pretreated patients than those in patients not receiving steroids. CONCLUSIONS Endotoxin is released during cardiopulmonary bypass from the region drained by the inferior vena cava. Steroid pretreatment may actually reduce endotoxin release during bypass.
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Affiliation(s)
- S Wan
- Division of Cardiothoracic Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, People's Republic of China
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Abstract
Neurological injury is a major and often debilitating complication of congenital heart disease and open-heart surgery. Paradoxically, the full impact of this complication has been underscored by the marked decrease in mortality and the rescue of infants with desperate and previously lethal heart conditions. Although recent focus has been on mechanisms of brain injury originating during open-heart surgery, this article also emphasizes the importance of mechanisms initiated or perpetuated during the preoperative and postoperative periods. In addition to the usually implicated mechanism of hypoxia-ischemia, recent genetic advances suggest an important role for genetic deletion syndromes. Inflammatory cascades have been implicated in the end-organ injury seen after cardiopulmonary bypass and might play a role in neurological dysfunction. These mechanisms are reviewed, with an emphasis on recent developments in our understanding of brain injury in this population.
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Affiliation(s)
- A J du Plessis
- Department of Neurology, Children's Hospital, Boston, MA 02115, USA
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Bruder N, Dumont JC. [Nutritional aspects of cranial trauma]. ANNALES FRANCAISES D'ANESTHESIE ET DE REANIMATION 1998; 17:186-91. [PMID: 9750721 DOI: 10.1016/s0750-7658(98)80073-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In head-injured patients the nutritional support is aimed to prevent denutrition status usually observed. The adequate amount of calories depends on the basal metabolism (as calculated with the Harris Benedict equation). It has to be increased in case of fever (by a 0.1 factor per degree above 37 degrees C), sepsis (by a 0.1 to 0.2 factor) or when sedation is discontinued (by a 0.3 factor). The increased proteolysis is not modified by the associated treatment and results in an inevitable protein loss, whatever the qualitative change in nutritional support. In clinical practice, the nutritional support has to be adjusted continuously to the needs of the patient, to avoid a more pronounced denutrition due to the summation of daily nutritional deficits.
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Affiliation(s)
- N Bruder
- Département d'anesthésie-réanimation, CHU Timone, Marseille, France
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Bruder N, Raynal M, Pellissier D, Courtinat C, François G. Influence of body temperature, with or without sedation, on energy expenditure in severe head-injured patients. Crit Care Med 1998; 26:568-72. [PMID: 9504588 DOI: 10.1097/00003246-199803000-00033] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To quantify the effect of body temperature and sepsis on energy expenditure in head-injured patients. DESIGN Prospective, nonrandomized, observational study. SETTING Neurosurgical intensive care unit. PATIENTS Severe head-injured patients. INTERVENTIONS Use of an indirect calorimeter to measure energy expenditure. MEASUREMENTS AND MAIN RESULTS Mean arterial pressure (MAP), heart rate (HR), body temperature, and mean hourly energy expenditure were recorded. Twenty-four patients had 1,919 hourly measures of the above parameters. The measurement periods were divided into four groups, according to the anesthetic agents used for sedation: fentanyl and midazolam (group FM); fentanyl, midazolam, and curarization (group C); thiopental (group T); and no sedation (group NS). The energy expenditure/basal energy expenditure ratio (EE/BEE) was significantly lower in group T (1.20 +/- 0.15) than in group FM (1.32 +/- 0.24) or group C (1.32 +/- 0.20) and was significantly higher in group NS (1.60 +/- 0.33). There was a significant correlation between body temperature and EE/BEE (p < .0001, r2 = .27) only in sedated patients. Using the equation of the regression line to correct energy expenditure for differences in body temperatures between groups, the difference in energy expenditure between groups with sedation disappeared. This finding suggested that the low energy expenditure under thiopental was due only to hypothermia. Sepsis significantly increased energy expenditure independently of fever. There was a weak but statistically significant correlation between energy expenditure and HR (p<.01, r2 = .13) but not between energy expenditure and MAP. CONCLUSIONS Sedation had a major effect on energy expenditure. In sedated patients, body temperature was the main determinant of energy expenditure; the anesthetic agent used had little influence on the level of energy expenditure. Sepsis increased energy expenditure independently of fever, probably through hormonal changes.
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Affiliation(s)
- N Bruder
- Département d'Anesthésie-Réanimation, CHU Timone, Marseille, France
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Martinez-Pellús AE, Merino P, Bru M, Canovas J, Seller G, Sapiña J, Fuentes T, Moro J. Endogenous endotoxemia of intestinal origin during cardiopulmonary bypass. Role of type of flow and protective effect of selective digestive decontamination. Intensive Care Med 1997; 23:1251-7. [PMID: 9470081 DOI: 10.1007/s001340050494] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To evaluate the possible related factors to endotoxemia and cytokine activation during the ischemic phase of extracorporeal surgery, and the effect of selective digestive decontamination (SDD) as a preventive measure. DESIGN Prospective, open, randomized trial. SETTING Two multidisciplinary ICUs (tertiary care hospitals). PATIENTS One hundred consecutive patients undergoing cardiopulmonary bypass (CPB), randomly allocated to two groups; gut decontamination (group I = 50 cases) and controls (group II = 50 cases). INTERVENTIONS Preoperative administration of oral non-absorbable antibiotics (polymyxin E, tobramycin and amphotericin B) versus no administration. MEASUREMENTS AND RESULTS The assessment of decontamination by means of the bacteriologic control of rectal swabs. Determinations of gastric intramucosal pH (gastric pHi) and plasma endotoxin, tumor necrosis factor (TNF) aNd interleukin-6 (IL-6) before surgery and during the ischemic and reperfusion phases of bypass. Rectal aerobic Gram-negative bacilli (AGNB) were significantly reduced in the treated patients and in 56% total eradication was achieved. Endotoxin, TNF and IL-6 plasma levels were significantly lower in this group. By contrast, both endotoxin and TNF/IL-6 levels and gastric pHi correlated with the type of surgical flow (pulsatile versus non-pulsatile). CONCLUSIONS SDD reduces the gut content of enterobacteria. This may explain the lower endotoxin and cytokine levels detected in decontaminated patients. In addition to SDD, the type of flow employed during bypass seems to influence endotoxemia and cytokine levels.
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Affiliation(s)
- A E Martinez-Pellús
- Intensive Care Unit, Hospital Universitario Virgen del la Arrixaca, El Palmar Murcia, Spain
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Wan S, LeClerc JL, Vincent JL. Inflammatory response to cardiopulmonary bypass: mechanisms involved and possible therapeutic strategies. Chest 1997; 112:676-92. [PMID: 9315800 DOI: 10.1378/chest.112.3.676] [Citation(s) in RCA: 596] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Recent study of the inflammatory reactions occurring during and after cardiopulmonary bypass (CPB) has improved our understanding of the involvement of the inflammatory cascade in perioperative injury. However, the exact mechanisms of this complex response remain to be fully determined. METHODS Literature on the inflammatory response to CPB was reviewed to define current knowledge on the possible pathways and mediators involved, and to discuss recent developments of therapeutic interventions aimed at attenuating the inflammatory response to CPB. RESULTS CPB has been shown to induce complement activation, endotoxin release, leukocyte activation, the expression of adhesion molecules, and the release of many inflammatory mediators including oxygen-free radicals, arachidonic acid metabolites, cytokines, platelet-activating factor, nitric oxide, and endothelins. Therapies aimed at interfering with the inflammatory response include the administration of pharmacologic agents such as corticosteroids, aprotinin, and antioxidants, as well as modification of techniques and equipment by the use of heparin-coated CPB circuits, intraoperative leukocyte depletion, and ultrafiltration. CONCLUSIONS Improved understanding of the inflammatory reactions to CPB can lead to improved patient outcome by enabling the development of novel therapies aimed at limiting this response.
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Affiliation(s)
- S Wan
- Department of Cardiac Surgery, University Hospital Erasme, Free University of Brussels, Belgium
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Oudemans-van Straaten HM, Scheffer GJ, Stoutenbeek CP. Analysis of P50 and oxygen transport in patients after cardiac surgery. Intensive Care Med 1996; 22:781-9. [PMID: 8880247 DOI: 10.1007/bf01709521] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine whether standard P50 after cardiac surgery decreases and whether decreased P50 is related to the transfusion of red blood cells (RBCs), acid-base changes, body temperature, oxygen parameters and/or duration of cardiopulmonary bypass (CPB). DESIGN Pilot study in cardiac surgery patients. SETTING University hospital. PATIENTS 12 Consecutive elective cardiac surgery patients. INTERVENTIONS Blood was taken before surgery, after CPB and in the intensive care unit until 18 h post-operatively. Cardiac output and oxygen consumption were measured. Buffy coat-poor RBCs were transfused, anticoagulated with citrate-phosphate-dextrose buffer and stored in saline-adenine-glucose-mannitol at 4 degrees C, when haemoglobin was < 5.6 mmol.l-1. MEASUREMENTS AND RESULTS Standard P50 was calculated from measured partial pressure of oxygen and of carbon dioxide, pH and oxygen saturation in mixed venous blood (SvO2) using the Severinghaus formula. Median length of RBC storage was 25 days. Standard P50 after surgery was significantly lower than baseline value (p = 0.0001). The number of RBC units transfused and duration of CPB were conjointly associated with P50 (R2 = 0.72). Patients who received more RBCs consumed more oxygen. CONCLUSION Cardiac surgery patients receiving more RBC units have lower standard P50 and consume more oxygen. P50 decreased more when the CPB took longer. Because a decrease in P50 implies a low ratio of mixed venous oxygen tension (PvO2) to SvO2, a shift in P50 should be taken into account when using SvO2 as a measure of global oxygen availability. When a direct measurement of SvO2 is not available, PvO2 should be used instead of calculated SvO2.
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