1
|
Edinger F, Holtz L, Schmidt G, Schneck E, Zajonz T, Sander M, Koch C. New Insights into Hepatic and Intestinal Microcirculation and Pulmonary Inflammation in a Model of Septic Shock and Veno-Arterial Extracorporeal Membrane Oxygenation in the Rat. Int J Mol Sci 2024; 25:7421. [PMID: 39000529 PMCID: PMC11242878 DOI: 10.3390/ijms25137421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/02/2024] [Accepted: 07/04/2024] [Indexed: 07/16/2024] Open
Abstract
Despite significant efforts toward improving therapy for septic shock, mortality remains high. Applying veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) in this context remains controversial. Since the cannulation of the femoral artery for V-A ECMO return leads to lower body hyperoxia, this study investigated the impact of V-A ECMO therapy on the intestinal and hepatic microcirculation during septic shock in a rodent model. Thirty male Lewis rats were randomly assigned to receive V-A ECMO therapy with low (60 mL/kg/min) or high (90 mL/kg/min) blood flow or a sham procedure. Hemodynamic data were collected through a pressure-volume catheter in the left ventricle and a catheter in the lateral tail artery. Septic shock was induced by intravenous administration of lipopolysaccharide (1 mg/kg). The rats received lung-protective ventilation during V-A ECMO therapy. The hepatic and intestinal microcirculation was measured by micro-lightguide spectrophotometry after median laparotomy for two hours. Systemic and pulmonary inflammation was detected via enzyme-linked immunosorbent assays (ELISA) of the plasma and bronchoalveolar lavage (BAL), respectively, measuring tumor necrosis factor-alpha (TNF-α), interleukins 6 (IL-6) and 10 (IL-10), and C-X-C motif ligands 2 (CXCL2) and 5 (CXCL5). Oxygen saturation and relative hemoglobin concentration were reduced in the hepatic and intestinal microcirculation during V-A ECMO therapy, independent of the blood flow rate. Further, rats treated with V-A ECMO therapy also presented elevated systolic, diastolic, and mean arterial blood pressure and increased stroke volume, cardiac output, and left ventricular end-diastolic volume. However, left ventricular end-diastolic pressure was only elevated during high-flow V-A ECMO therapy. Blood gas analysis revealed a dilutional anemia during V-A ECMO therapy. ELISA analysis showed an elevated plasma CXCL2 concentration only during high-flow V-A ECMO therapy and elevated BAL CXCL2 and CXCL5 concentrations only during low-flow V-A ECMO therapy. Rats undergoing V-A ECMO therapy exhibited impaired microcirculation of the intestine and liver during septic shock despite increased blood pressure and cardiac output. Increased pulmonary inflammation was detected only during low-flow V-A ECMO therapy in septic shock.
Collapse
Affiliation(s)
- Fabian Edinger
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Lena Holtz
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Götz Schmidt
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Emmanuel Schneck
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Thomas Zajonz
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Michael Sander
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| | - Christian Koch
- Department of Anesthesiology, Critical Care Medicine and Pain Therapy, University Hospital of Giessen, Justus-Liebig-University, 35392 Giessen, Germany
| |
Collapse
|
2
|
Edinger F, Zajonz T, Holtz L, Schmidt G, Schneck E, Sander M, Koch C. New Insights into Hepatic and Intestinal Microcirculation and Pulmonary Inflammation in a Model of Septic Shock and Venovenous Extracorporeal Membrane Oxygenation in the Rat. Int J Mol Sci 2024; 25:6621. [PMID: 38928327 PMCID: PMC11203541 DOI: 10.3390/ijms25126621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 06/09/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024] Open
Abstract
Treatment of critically ill patients with venovenous (V-V) extracorporeal membrane oxygenation (ECMO) has gained wide acceptance in the last few decades. However, the use of V-V ECMO in septic shock remains controversial. The effect of ECMO-induced inflammation on the microcirculation of the intestine, liver, and critically damaged lungs is unknown. Therefore, the aim of this study was to measure the hepatic and intestinal microcirculation and pulmonary inflammatory response in a model of V-V ECMO and septic shock in the rat. Twenty male Lewis rats were randomly assigned to receive V-V ECMO therapy or a sham procedure. Hemodynamic data were measured by a pressure-volume catheter in the left ventricle and a catheter in the lateral tail artery. Septic shock was induced by the intravenous infusion of lipopolysaccharide (1 mg/kg). During V-V ECMO therapy, rats received lung-protective ventilation. The hepatic and intestinal microcirculation was assessed by micro-lightguide spectrophotometry after median laparotomy for 2 h. Systemic and pulmonary inflammation was measured by enzyme-linked immunosorbent assays of plasma and bronchoalveolar lavage (BAL), respectively, which included tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-10, C-X-C motif ligand 2 (CXCL2), and CXCL5. Reduced oxygen saturation and relative hemoglobin concentration were measured in the hepatic and intestinal microcirculation during treatment with V-V ECMO. These animals also showed increased systolic, mean, and diastolic blood pressures. While no differences in left ventricular ejection fraction were observed, animals in the V-V ECMO group presented an increased heart rate, stroke volume, and cardiac output. Blood gas analysis showed dilutional anemia during V-V ECMO, whereas plasma analysis revealed a decreased concentration of IL-10 during V-V ECMO therapy, and BAL measurements showed increased concentrations of TNF-α, CXCL2, and CXCL5. Rats treated with V-V ECMO showed impaired microcirculation of the intestine and liver during septic shock despite increased blood pressure and cardiac output. Despite lung-protective ventilation, increased pulmonary inflammation was recognized during V-V ECMO therapy in septic shock.
Collapse
Affiliation(s)
| | - Thomas Zajonz
- Department of Anesthesiology, Operative Intensive Care Medicine and Pain Therapy, University Hospital, Justus-Liebig-University, 35392 Giessen, Germany
| | | | | | | | | | | |
Collapse
|
3
|
Jia T, Xing Z, Wang And H, Li G. Protective effect of dexmedetomidine on intestinal mucosal barrier function in rats after cardiopulmonary bypass. Exp Biol Med (Maywood) 2021; 247:498-508. [PMID: 34878923 DOI: 10.1177/15353702211062509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Cardiopulmonary bypass can result in damage to the intestines, leading to the occurrence of systemic inflammatory response syndrome. Dexmedetomidine is reported to confer anti-inflammatory properties. Here, the purpose of this study is to investigate the effect of dexmedetomidine on the intestinal mucosa barrier damage in a rat model of cardiopulmonary bypass. It was observed that cardiopulmonary bypass greatly decreased the levels of hemodynamic parameters than SHAM group, whereas dexmedetomidine pretreatment in a cardiopulmonary bypass model rat prevented this reduction. Also, it showed that compared with control animals, cardiopulmonary bypass caused obvious mucosal damage, which was attenuated in dexmedetomidine + cardiopulmonary bypass group. The above findings were in line with that of dexmedetomidine pretreatment, which increased the expression of tight junction proteins, but it decreased the levels of DAO, D-LA, FABP2, and endotoxin. Moreover, the results demonstrated that due to pre-administration of dexmedetomidine, the level of pro-inflammatory factors was decreased, while the level of anti-inflammatory cytokine was increased. Also, it showed that dexmedetomidine suppressed TLR4/JAK2/STAT3 pathway that was activated by cardiopulmonary bypass. Together, these results revealed that dexmedetomidine pretreatment relieves intestinal microcirculation, attenuates intestinal damage, and inhibits the inflammatory response of cardiopulmonary bypass model rats, demonstrating that in CPB-induced damage of intestinal mucosal barrier function, dexmedetomidine pretreatment plays a protective role by inactivating TLR4/JAK2/STAT3-mediated inflammatory pathway.
Collapse
Affiliation(s)
- Tong Jia
- Anesthesiology Department, The First Affiliated Hospital of Hebei North University, Zhangjiakou 075000, P. R. China
| | - Zhen Xing
- Anesthesiology Department, The First Affiliated Hospital of Hebei North University, Zhangjiakou 075000, P. R. China
| | - Huijuan Wang And
- Anesthesiology Department, The First Affiliated Hospital of Hebei North University, Zhangjiakou 075000, P. R. China
| | - Guoli Li
- Anesthesiology Department, The First Affiliated Hospital of Hebei North University, Zhangjiakou 075000, P. R. China
| |
Collapse
|
4
|
Donndorf P, Park H, Vollmar B, Alms A, Gierer P, Steinhoff G, Kaminski A. Impact of closed minimal extracorporeal circulation on microvascular tissue perfusion during surgical aortic valve replacement: intravital imaging in a prospective randomized study. Interact Cardiovasc Thorac Surg 2014; 19:211-7. [PMID: 24796334 DOI: 10.1093/icvts/ivu131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES Closed minimal extracorporeal circulation (MECC) systems currently do not represent the standard of surgical care for open-heart surgery. Yet, considering the beneficial results reported for coronary artery bypass graft (CABG) surgery, we used an MECC system in aortic valve replacement (AVR) and analysed the effects on intraoperative microvascular perfusion in comparison with conventional open extracorporeal circulation (CECC). METHODS In the current study, we analysed alterations in microvascular perfusion at 4 predefined time points (T1-T4) during surgical AVR utilizing orthogonal polarization spectral (OPS) imaging. Twenty patients were randomized for being operated on utilizing either MECC or CECC. Changes in functional capillary density (FCD, cm/cm(2)), mircovascular blood flow velocity (mm/s) and vessel diameter (μm) were analysed by a blinded investigator. RESULTS After the start of extracorporeal circulation and aortic cross-clamping (T2), both groups showed a significant drop in FCD, but with a significantly higher FCD in the MECC group (153.1 ± 15.0 cm/cm² in the CECC group vs 160.8 ± 12.2 cm/cm² in the MECC group, P = 0.034). During the late phase of the cardiopulmonary bypass (CPB) (T3), the FCD was still significantly depressed in both treatment groups (153.5 ± 14.6 cm/cm² in the CECC group, P <0.05 vs 'T1'; 159.5 ± 12.4 cm/cm² in the MECC group, P <0.05 versus 'T1'). After termination of CPB (T4), the FCD recovered in both groups to baseline values. Microvascular blood flow velocity tended to remain at a higher level in the MECC group, whereas haemodilution during CPB was significantly reduced in the MECC group. CONCLUSIONS The use of MECC in AVR did not affect procedural safety and, resulted in beneficial preservation of microvascular blood flow velocity and significantly reduced haemodilution during CPB. In contrast to CABG surgery, the use of MECC did not improve FCD during surgical AVR. Clinical advantages possibly resulting from attenuated haemodilution and preservation of microvascular blood flow velocity require further validation in larger patient cohorts.
Collapse
Affiliation(s)
- Peter Donndorf
- Department of Cardiac Surgery, University of Rostock, Rostock, Germany
| | - Hannah Park
- Department of Cardiac Surgery, University of Rostock, Rostock, Germany
| | - Brigitte Vollmar
- Institute of Experimental Surgery, University of Rostock, Rostock, Germany
| | - Angela Alms
- Department of Anesthesiology and Intensive Care Medicine, University of Rostock, Rostock, Germany
| | - Philipp Gierer
- Department of Trauma and Reconstructive Surgery, University of Rostock, Rostock, Germany
| | - Gustav Steinhoff
- Department of Cardiac Surgery, University of Rostock, Rostock, Germany
| | | |
Collapse
|
5
|
Yang L, Wang S, Li CS. Effect of continuous compression and 30:2 cardiopulmonary resuscitation on cerebral microcirculation in a porcine model of cardiac arrest. Scand J Trauma Resusc Emerg Med 2013; 21:55. [PMID: 23849600 PMCID: PMC3750813 DOI: 10.1186/1757-7241-21-55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 07/10/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The effect of rescue breathing on neurologic prognosis after cardiopulmonary resuscitation (CPR) is controversial. Therefore, we investigated the cerebral microcirculatory and oxygen metabolism during continuous compression (CC) and 30:2 CPR (VC) in a porcine model of cardiac arrest to determine which is better for neurologic prognosis after CPR. METHODS After 4 min of ventricular fibrillation, 20 pigs were randomised into two groups (n=10/group) receiving CC-CPR or VC-CPR. Cerebral oxygen metabolism and blood flow were measured continuously using laser Doppler flowmetry. Haemodynamic data were recorded at baseline and 5 min, 30 min, 2 h and 4 h after restoration of spontaneous circulation (ROSC). RESULTS Compared with the VC group, the mean cortical cerebral blood flow was significantly higher at 5 min ROSC in the CC group (P<0.05), but the difference disappeared after that time point. Brain percutaneous oxygen partial pressures were higher, and brain percutaneous carbon dioxide partial pressures were lower, in the VC group from 30 min to 4 h after ROSC; significant differences were found between the two groups (P<0.05). However, no significant difference of the cerebral oxygen extraction fraction existed between the two groups. CONCLUSIONS Inconsistency of systemic circulation and cerebral microcirculation with regard to blood perfusion and oxygen metabolism is common after CPR. No significant differences in cortical blood flow and oxygen metabolism were found between the CC-CPR and VC-CPR groups after ROSC.
Collapse
Affiliation(s)
- Lin Yang
- Department of Emergency Medicine, Beijing Chao-Yang Hospital, Affiliated to Capital Medical University, Chaoyang District, Beijing 100020, China
| | | | | |
Collapse
|
6
|
Sun YJ, Cao HJ, Song DD, Diao YG, Zhou J, Zhang TZ. Probiotics can alleviate cardiopulmonary bypass-induced intestinal mucosa damage in rats. Dig Dis Sci 2013; 58:1528-36. [PMID: 23334383 DOI: 10.1007/s10620-012-2546-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 12/24/2012] [Indexed: 12/12/2022]
Abstract
BACKGROUND Cardiopulmonary bypass (CPB) is commonly applied to support circulation during heart surgery but frequently causes adverse effects. AIMS The purpose of this study was to examine the potential of probiotics to improve small intestinal mucosa barrier function after CPB. METHODS Twenty-four adult male SD rats were randomly divided into sham-operated (S), CPB-operated (CPB), and probiotic-fed (Y) groups. Diamine oxidase (DAO) activity and concentrations of D-lactic acid, endotoxin, TNFα, and IL-6 were measured in portal vein blood. IgA concentrations were determined in plasma and the small intestine. Vena cava blood and tissue samples were used to monitor bacterial growth. Intestinal epithelial ultrastructure was analyzed by transmission electron microscopy (TEM). Occludin and ZO-1 expression levels in the intestinal epithelium were detected by western blotting and immunohistochemistry, respectively. RESULTS D-lactic acid, endotoxin, TNFα and IL-6 levels, DAO activity, and bacterial translocation rate were increased (P < 0.05) in CPB and Y compared to the S group. The above indices were relatively lower (P < 0.05) in Y than in CPB. Plasma and small intestinal IgA levels were significantly lower (P < 0.05) in CPB, while in Y they were significantly increased (P < 0.05) but lower than in S (P < 0.05). These results were confirmed by TEM. Consistently, occludin and ZO-1 expression levels were significantly higher in Y than in CPB (P < 0.05) but still lower compared to S (P < 0.05). CONCLUSION Pre-administration of probiotics can improve, to some extent, intestinal barrier function after CPB in rats, and this effect is likely related to inhibition of the CPB-induced inflammatory response, improvement in local intestinal immune function, and increased expression of intestinal epithelial tight junction proteins.
Collapse
Affiliation(s)
- Ying-Jie Sun
- Department of Anesthesiology, General Hospital of Shenyang Commend, Shenyang, 110840, China
| | | | | | | | | | | |
Collapse
|
7
|
Donndorf P, Kühn F, Vollmar B, Rösner J, Liebold A, Gierer P, Steinhoff G, Kaminski A. Comparing microvascular alterations during minimal extracorporeal circulation and conventional cardiopulmonary bypass in coronary artery bypass graft surgery: A prospective, randomized study. J Thorac Cardiovasc Surg 2012; 144:677-83. [DOI: 10.1016/j.jtcvs.2012.05.037] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 04/04/2012] [Accepted: 05/15/2012] [Indexed: 10/28/2022]
|
8
|
Ranucci M, Aronson S, Dietrich W, Dyke CM, Hofmann A, Karkouti K, Levi M, Murphy GJ, Sellke FW, Shore-Lesserson L, von Heymann C. Patient blood management during cardiac surgery: Do we have enough evidence for clinical practice? J Thorac Cardiovasc Surg 2011; 142:249.e1-32. [DOI: 10.1016/j.jtcvs.2011.04.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 02/09/2011] [Accepted: 04/08/2011] [Indexed: 12/13/2022]
|
9
|
Cai DS, Jin BB, Pei L, Jin Z. Protective effects of penehyclidine hydrochloride on liver injury in a rat cardiopulmonary bypass model. Eur J Anaesthesiol 2010; 27:824-8. [PMID: 20523213 DOI: 10.1097/eja.0b013e32833b650f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND OBJECTIVE Hepatic injury after cardiac surgery is considered to be a consequence of cardiopulmonary bypass (CPB). The aim of this study was to test the hypothesis that penehyclidine hydrochloride (PHC) could attenuate hepatic injury using a rat CPB model. METHODS Male Sprague-Dawley rats were randomly divided into six groups (eight per group), including sham-operated control, sham low-dose PHC control (0.6 mg kg), sham high-dose PHC control (2.0 mg kg), vehicle control, low-dose PHC (0.6 mg kg) and high-dose PHC (2.0 mg kg)-treated groups. Blood samples were collected from the femoral artery at the cessation of CPB and the serum levels of the liver enzymes, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), were determined. The ultrastructure of liver tissue was also examined under an electron microscope. RESULTS In the sham-operated groups, high-dose PHC and low-dose PHC had no significant impact on the levels of respiratory rate, heart rate, blood pressure, ECG, ALT or AST. Compared with the sham group, the serum levels of ALT and AST were increased significantly in the surgical groups. PHC alleviated all the biochemical and histopathological changes in a dose-dependent manner. The ALT and AST levels in the high-dose PHC-treated groups were significantly lower than those in the vehicle control group. CONCLUSION Treatment with penehyclidine hydrochloride could improve liver function during CPB.
Collapse
Affiliation(s)
- Da-Sheng Cai
- Department of Anesthesiology, The First University Hospital of China Medical University, Shenyang, China
| | | | | | | |
Collapse
|
10
|
Berger K, Sander M, Spies C, Weymann L, Bühner S, Lochs H, Wernecke KD, von Heymann C. Profound haemodilution during normothermic cardiopulmonary bypass influences neither gastrointestinal permeability nor cytokine release in coronary artery bypass graft surgery. Br J Anaesth 2009; 103:511-7. [DOI: 10.1093/bja/aep201] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
|
11
|
Solligård E, Wahba A, Skogvoll E, Stenseth R, Grønbech JE, Aadahl P. Rectal lactate levels in endoluminal microdialysate during routine coronary surgery. Anaesthesia 2007; 62:250-8. [PMID: 17300302 DOI: 10.1111/j.1365-2044.2006.04937.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The aim of this prospective study was to determine the feasibility of intestinal endoluminal microdialysis as a new method for clinical monitoring of the adequacy of splanchnic perfusion in the large bowel. A microdialysis catheter for continuous lactate, glycerol, glucose and pyruvate measurements attached to a tonometric catheter was placed into the lumen of the recto-sigmoid junction prior to surgery in 13 patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB). Lactate was also measured in blood and muscle. CPB was associated with a 10-fold increase in luminal lactate from 0.16 (0.01) to 1.67 (0.38) mmol x l(-1) (p < 0.001). Muscular lactate increased from baseline levels 1.20 (0.21) to 1.77 (0.36) mmol x l(-1) during CPB (p = 0.01), but the muscular lactate-pyruvate ratio remained unchanged. Arterial lactate increased only slightly from 0.9 (0.05) to 1.1 (0.06) mmol x l(-1) (p = 0.027) during CPB. Increased lactate concentrations in the large bowel during CPB are suggestive of local lactate production consistent with impaired oxygen delivery. Intestinal endoluminal microdialysis is a potential clinically applicable method for monitoring intestinal metabolism. Combined with tonometry, microdialysis provides the opportunity to monitor both circulation and metabolism in the rectal mucosa.
Collapse
Affiliation(s)
- E Solligård
- Department of Anaesthesiology and Intensive Care, St Olav University Hospital, Norwegian University of Science and Technology, N-7006 Trondheim, Norway.
| | | | | | | | | | | |
Collapse
|
12
|
Nygren A, Thorén A, Houltz E, Ricksten SE. Autoregulation of Human Jejunal Mucosal Perfusion During Cardiopulmonary Bypass. Anesth Analg 2006; 102:1617-22. [PMID: 16717297 DOI: 10.1213/01.ane.0000219596.34753.72] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Animal studies have suggested that autoregulation of intestinal blood flow is severely impaired during cardiopulmonary bypass (CPB). We investigated the jejunal mucosal capacity to autoregulate perfusion during nonpulsatile CPB (34 degrees C) in 10 patients undergoing elective cardiac surgery. Changes in mean arterial blood pressure (MAP) were induced by altering the CPB flow rate randomly for periods of 3 min from 2.4 L/min/m2 to either 1.8 or 3.0 L/min/m2. Jejunal mucosal perfusion (JMP) was continuously recorded by laser Doppler flowmetry. A typical pattern of flow motion (vasomotion) was recorded in all patients during CPB. Variations in CPB flow rates caused no significant changes in mean JMP, jejunal mucosal hematocrit, or red blood cell velocity within a range of MAP from 50 +/- 15 to 74 +/- 16 mm Hg. The vasomotion frequency and amplitude was positively correlated with CPB flow rate. IV injections of prostacyclin (10 microg, Flolan) blunted vasomotion and increased JMP from 192 +/- 53 to 277 +/- 70 (P < 0.05) perfusion units despite a reduction in MAP from 59 +/- 12 to 45 +/- 10 mm Hg (P < 0.05). Prostacyclin-induced vasodilation resulted in loss of mucosal autoregulation (pressure-dependent perfusion). We conclude that autoregulation of intestinal mucosal perfusion is maintained during CPB in humans.
Collapse
Affiliation(s)
- Andreas Nygren
- Department of Cardiothoracic Anesthesia and Intensive Care, Sahlgrenska University Hospital, 41345 Göteborg, Sweden
| | | | | | | |
Collapse
|