Reiji Wakusawa

Elevation of cytokines during open heart surgery with cardiopulmonary bypass : participation of interleukin 8 and 6 in reperfusion injury

Myocardial ischaemia is one of the major causes of low output syndrome during open heart surgery. Injury associated with ischaemia and reperfusion has been considered to result, in part, from the action of neutrophils, the interaction of neutrophils with vascular endothelial cells, and the effects of cytokines which are mediators that induce and modify reactions between these substances. We investigated cell injury in relation to the concentrations of interleukins 6 and 8 (IL-6 and IL-8), which have recently received attention as neutrophil activators. Neutrophil counts, granulocyte elastase (GEL), IL-6, IL-8, tumour necrosis factor-α (TNF-α), CK, and CK-MB concentrations were determined serially in 11 patients undergoing open heart surgery with cardiopulmonary bypass (CPB). Neutrophil counts (mean ±SD 2717 ±2421 μl−1 preoperatively) peaked 60 min after declamping the aorta at 7432 ±4357 μl−1 (P < 0.01) and remained elevated 7136 ±5194 μl−1 at 180 min (P < 0.01). Plasma GEL level (168 ±71 μg sd L−1 preoperatively) peaked at 1134 ±453 μg · L−1 120 min after declamping of the aorta (P < 0.01) and remained elevated, 1062 ±467 μg · L−1, after 180 min (P < 0.01). Serum IL-6 level (118 ±59 pg · ml−1 preoperatively) peaked at 436 ±143 pg · ml−1 60 min after declamping of the aorta (P < 0.01) and remained elevated, 332 ±109 pg · ml−1, after 180 min. Serum IL-8 level (37 ±44 pg · ml−1 preoperatively) peaked at 169 ±86 pg · ml−1 at 60 min after declamping of the aorta (P < 0.001) and remained elevated at 113 ±78 pg · ml−1 180 min after declamping of the aorta. Serum TNF-α was decreased at 60 min after aortic occlusion but otherwise did not change. Plasma GEL concentrations correlated with serum IL-8 levels (R = 0.7, P = 0.001) and the IL-6 and IL-8 concentrations correlated with the duration of aortic clamping (R = 0.64, P = 0.01, R = 0.7, P = 0.01). We conclude that the increases of IL-6 and IL-8 occur as a result of ischaemia, and suggest that these cytokines participate in reperfusion injury by activating neutrophils.RésuméL’ischémie myocardique est une des principales causes du syndrome de bas débit pendant la chirurgie à coeur ouvert. On pense que la lésion associée à l’ischémie et la reperfusion résulte en partie de l’action des neutrophiles, l’interaction des neutrophiles avec les cellules vasculaires endothéliales et l’activité de médiateurs, les cytokines qui induisent et modifient les réactions entre ces substances. Nous avons examiné la relation de la lésion cellulaire avec la concentration des interleukines 6 et 8 (IL-6 et IL-8), qui ont récemment attiré l’attention comme activateurs de neutrophiles. Chez 11 patients soumis à une chirurgie cardiaque ouverte avec circulation extracorporelle (CEC), on mesure en série le décompte des neutrophiles, l’élastase granulocytaire (GEL), l’IL-6 et l’IL-8, le facteur-α. de nécrose tumorale (TNF-α) et la concentration des CK et CK-MB. Le décompte des neutrophiles (moyenne ±SD: 2717 ±2421 μl−1 en préopératoire) atteint un maximum de 7432 ±435 μl−1 60 min après le déclampage de l’aorte (P < 0,01) et demeure élevé, 7136 ±5194 μl−1, à 180 min (P < 0,01). Le niveau de la GEL plasmatique (168 ±71 μg · L−1 en préopératoire) atteint un maximum de 1134 ±453 μg · L−1 après 120 min du déclampage de l’aorte (P < 0,01) et demeure élevé, 1062 ±467 μg · L−1 après 180 min de déclampage (P < 0,01). L’IL-6 sérique (118 ±59 pg · ml−1) atteint un maximum de 436 ±143 pg · ml−1 60 minutes après le déclampage de l’aorte (P < 0,01) et demeure élevé, 332 ±109 pg · ml−1 après 180 min. Le niveau sérique d’IL-8 (37 ±44 pg · ml−1 en préopératoire) atteint un maximum de 169 ±86 pg · ml−1 60 min après le déclampage de l’aorte (P < 0,01) et demeure élevé, 113 ±78 pg · ml−1 après 180 min. Le TNF-α décroît 60 min après le clampage aortique mais ne change plus par la suite. La concentration plasmatique de GEL est en corrélation avec le niveau sérique de l’IL-8 (R = 0,7, P = 0,001). Les concentrations d’IL-6 et d’IL-8 sont en corrélation avec la durée du clampage (R = 0,64, P = 0,01, R = 0,07, P = 0,01). Nous concluons que les augmentations d’IL-6 et d’IL-8 résultent de l’ischémie et nous suggérons qu’en activant les neutrophiles, ces cytokines participent à la genèse de la lésion de reperfusion.

Influence of methylprednisolone on cytokine balance during cardiac surgery

OBJECTIVE To determine the influence of methylprednisolone on the cytokine balance during cardiac surgery. DESIGN Prospective, randomized, nonblinded study. SETTING University hospital. PATIENTS Twenty-one patients on cardiopulmonary bypass undergoing aortocoronary bypass surgery. INTERVENTIONS According to a randomized sequence, the patients either received methylprednisolone (30 mg/kg) [corrected] before cardiopulmonary bypass and before declamping of the aorta (MPS group, n = 11) or received nothing (control group, n = 10). MEASUREMENTS AND MAIN RESULTS Serum proinflammatory cytokines (interleukin [IL]-8, IL-6) and anti-inflammatory cytokines (IL-10, IL-1ra) were measured by enzyme-linked immunosorbent assays. Serum IL-6 and IL-8 concentrations in the control group (15.2 +/- 4.1 and 14.1 +/- 1.9 pg/mL, preoperatively) increased to 242 +/- 70.1 and 97.3 +/- 18.3 pg/mL at 60 mins after declamping of the aorta (p < .01, p < .01, respectively). The increases were greater than those from 2.5 +/- 0.6 and 2.5 +/- 0.5 pg/mL to 109.5 +/- 29.0 and 33 +/- 4.1 pg/mL in the MPS group for IL-6 and IL-8, respectively. Serum IL-10 concentrations increased significantly 60 mins after declamping of the aorta compared with its preoperative value in the two groups (the control group, from 1.0 +/- 0 to 537.9 +/- 61.7 pg/mL; the MPS group, from 0.3 +/- 0.2 to 654.9 +/- 24 pg/mL [p < .01, p < .01, respectively]). No difference was found between the two groups. Similarly, serum IL-1ra concentrations in the two groups increased the preoperative value in the control group from 304 +/- 120 to 44,374 +/- 14,631 pg/mL and in the MPS group from 616.5 +/- 109.6 to 35,598 +/- 9,074 pg/mL at 60 mins after declamping of the aorta (p < .01, p < .01, respectively). There was no difference between the two groups. CONCLUSIONS Methylprednisolone reduces the production of IL-6 and IL-8 but not that of IL-10 and IL-1ra. These results suggest that one of the mechanisms of the cytoprotective effect of methylprednisolone may be to make changes in the proinflammatory and anti-inflammatory cytokine balance.

Methylprednisolone inhibits increase of interleukin 8 and 6 during open heart surgery

It has been reported that interleukin 8 (IL-8) and interleukin 6 (IL-6) are two of the chemical mediators causing myocardial injury. It is not clear whether treatment with corticosteroids in vitro in these patients can prevent the production of interleukin 8 and 6. This prospective study was conducted to investigate whether methylprednisolone (MP) pretreatment (30 mg · kg−1 before CPB and before declamping of aorta) influenced the production of IL-8 and 6 in the peripheral circulation in 27 patients undergoing elective coronary artery bypass surgery. The IL-8 and IL-6 concentrations were measured by ELISA kit. We also studied the effect of MP pretreatment on postoperative cardiac Junction. Serum concentration of IL-8 in non-MP-treated patients (37 ± 44 pg · ml−1 preoperatively) increased to 169 ± 86 pg · ml−1 60 min after declamping of the aorta (P < 0.001). The increase was greater than the increase from 22 ± 8.9 pg · ml−1 to 52 ± 35 pg · ml−1 in the MP-treated patients (P < 0.01). Serum IL-6 concentration in non-MP-treated patients increased from the preoperative value of 59 ± 30 pg · ml−1 to 436 ± 143 pg · ml−1 60 min after declamping of the aorta (P < 0.001). The increase was greater than the increase from 36 ± 15 pg · ml−1 to 135 ± 55 pg · ml−1 in the MP-treated patients (P < 0.01). Furthermore, postoperative cardiac index in MP-treated patients (3.6 ± 1.1 L · min−1· m−2) was higher than 2.3 ± 0.8 L · min−1 · m−2 of non MP-treated patients (P < 0.05). The levels of IL-8 max during surgery correlated negatively with postoperative cardiac index (γ = −0.67). These results suggest that methylprednisolone suppresses production of IL-8 and 6.RésuméOn a rapporté que l’interleukine 8 (IL-8) et que l’interleukine 6 (IL-6) étaient deux des médiateurs chimiques de la lésion cardiaque. Toutefois, on ne sait pas encore si le traitement aux corticostéroïdes in vivo prévient la production des interleukines 8 et 6. Cette étude prospective vise à déterminer si le prétraitement à la méthylprednisolone (MP) (30 mg · kg−1 avant le CEC et avant le déclampage de l’aorte) influence la concentration de l’IL-8 de l’IL-6 du sang veineux périphérique de 27 patients soumis à une chirurgie réglée de revascularisation myocardique. Les concentrations de l’IL-8 de l’IL-6 sont mesurée avec une trousse Elisa. Nous étudions aussi les répercussions du traitement à la MP sur la fonction cardiaque postopératoire. La concentration sérique de l’IL-8 des patients non traités (37 ± 44 pg · ml−1 en préopératoire) augmente à 169 ± 86 pg · ml−1 60 minutes après le déclampage de l’aorte (P < 0,001). Cette augmentation est plus importante que l’augmentation de 22 ± 8,9 pg · ml−1 à 52 ± 55 pg · ml−1 notée chez les patients traité à la MP (P < 0,01). La concentration serique de l’IL-6 chez les patients non traités à la MP augmente de la valeur préopératoire de 59 ± 30 pg · ml−1 à 436 ± 143 pg · ml−1 60 min après le déclampage de l’aorte (P < 0,001). Cette augmentation est plus importante que celle de 36 ± 15 pg · ml−1 à 135 ± 55 pg · ml−1 survenue chez les patients traités à la MP (P < 0,01). De plus, l’index cardiaque postopératoire des patients traités à la MP (3,6 ± 1,1 L · ml−1 · m−2) est plus élevé que celui des patients non traités 2,3 ± 0,8 L · ml−1 · m− 2 (P < 0,05). Les niveaux maximaux de 1’IL-8 sont en corrélation négative avec l’index cardiaque postopératoire (y = 0,67). Ces resultats suggèrent que la méthylprednisolone supprime la production de l’IL-8 et de l’IL-6.

Hepatic blood flow and function in elderly patients undergoing laparoscopic cholecystectomy.

Laparoscopic cholecystectomy (LC) has been widely accepted as an alternative to laparotomy and has many advantages, including short hospital stay and very limited surgical invasion. However, this procedure may impair hepatic function in elderly patients because high pressure is maintained in the peritoneal cavity for an extended period. We observed the effect of pneumoperitoneum on the middle hepatic venous blood flow (MHVBF) in elderly patients undergoing LC. LC patients were anesthesized with inhaled and epidural anesthesia, after which MHVBF was continuously measured by transesophageal echocardiography. MHVBF decreased significantly during a period of high intraperitoneal pressure, and recovery of MHVBF after deflation was significantly lower in elderly patients (65–75 yr), but not in younger patients (24–62 yr). In contrast, MHVBF remained almost constant in elderly patients during open cholecystectomy, and thus was significantly different from that in patients who underwent LC with pneumoperitoneum. Laparoscopic cholecystectomy may impair hepatic function in elderly patients because high pressure is maintained in the peritoneal cavity for an extended period. Implications We observed the effect of pneumoperitoneum on the middle hepatic venous blood flow by transesophageal echocardiography and liver function in elderly patients undergoing laparoscopic cholecystectomy. Laparoscopic cholecystectomy may impair hepatic function in elderly patients because high pressure is maintained in the peritoneal cavity for an extended period.

Interleukin-10 and interleukin-1 receptor antagonists increase during cardiac surgery

BackgroundIt has been reported that inflammatory cytokines such as interleukin-8 and 6 (IL-8, IL-6) increase during cardiac surgery and cause postoperative cardiac dysfunction. Therefore, it is important to investigate changes of suppressive cytokines such as IL-10, interleukin-4 (IL-4) and interleukin-1 receptor antagonist (IL-1 ra) dunng cardiac surgery.MethodSerum levels of cytokines and IL-1 ra were measured in 10 patients during cardiac surgery with cardiopulmonary bypass. Six blood samples were drawn after inducing anaesthesia. In each sample, serum IL-10, IL-4, IL-8, IL-6 and IL-1 ra were measured by enzyme linked immunosorbent assay.ResultsSerum IL-6 and IL-8 concentration (19.1 ±8.8 pg · ml−1, and 13.4±5.2 pg · ml−1, preoperatively) increased to 227.5± 191 pg · ml−1 and 81.0±56 pg · ml−1 at 60 min after declamping the aorta (P< 0.01, respectively). Serum IL-10 concentration increased at 60 min after dedamping the aorta compared with the preoperative value (from 1.0±0 pg · ml−1 to 552.0± 158 pg · ml−1 P< 0.001]). Similarly, serum IL-1 ra concentration increased from the preoperative value of 1331±896 pg · ml−1 to 43353±12812 pg · ml−1 at 60 min after dedamping the aorta (P< 0.00l). Positive correlations were obtained between IL-10 and IL-8. and between IL-10 and IL-6 (γ=0.7, γ=0.8, P< 0.001, respectively).ConclusionThese findings demonstrate that pro-and anti-inflammatory cytokines increase to maintain their balance during cardiac surgery.RésuméObjectifOn a rapporté que la concentration des cytokines de l’inflammation comme les interleukines 6 et 8 (IL-8. IL-6) s’élevaient pendant la chirurgie cardiaque et provoquaient des dérangements cardiaques postopératoires. II est donc aussi important d’examiner les perturbations produites par les cytokines suppressives comme IL-10, interleukine-4 (IL-4) et de l’antagoniste du récepteur de l’interleukine-1 (IL-1 ra) pendant la chirurgie cardiaque.MéthodesLa concentration sérique des cytokines et de IL-1 ra a été mesurée chez dix patients pendant une chirurgie cardiaque sous CEC. Six échantillons de sang ont été prélevés après l’induction de l’anesthésie. Dans chacun des échantillons. on a titré IL-10, IL-4, IL-8, IL-6 et IL-1 ra avec l’épreuve de l’immuno-absorption enzymatique.RésultatsLes concentrations de IL-6 et de IL-8 (valeurs préopératoires : 19, 1 ±8, 8 pg · ml−1 et 13.4±5.2 pg · ml−1) ont augmenté à 227,45±191 pg · ml−1 et 81, 0±56 pg · ml−1 60 min après le dédampage de l’aorte (respectivement P< 0, 01 ). La concentration sérique de IL-10 a augmenté 60 min après le dédampage de l’aorte comparativement aux valeurs préopératoires (de 1.0±0 pg · ml−1 à 552± 158 pg · ml−1, P < 0.001). De la même façon, la concentration sérique de IL-1 ra a augmenté de la valeur préopératoire de 1331 ±896 pg · ml−1 à 4 3353± 1 2812 pg · ml−1 60 min après le dédampage (P < 0,001). La corrélation était positive entre IL-10 et IL-8 et entre IL-10 et IL-6 (respectivement γ=0.7, γ=0.8, P < 0,001).ConclusionCes données montrent que les cytokines pro- et anti-inflammatoires augmentent pour maintenir leur équilibre pendant la chirurgie cardiaque.

Ulinastatin reduces elevation of cytokines and soluble adhesion molecules during cardiac surgery

PurposeTo investigate whether ulinastatin pretreatment (6000 U · kg−1 before CPB and before declamping of aorta) influenced the production of cytokines and adhesion molecules in the peripheral circulation.MethodsThis prospective randomized study was performed in 22 patients undergoing cardiac surgery. They were divided into two groups. Patients in Group I were untreated and in Group II treated with ulinastatin. The soluble intercellular adhesion molecule-1 (S-ICAM-1), soluble endothelial leukocyte adhesion molecule-1 (S-ELAM-1), interleukin8 and 6 (IL-8, 6) were measured using ELISA kits.ResultsSerum S-ICAM-1 concentration in Group I increased from the preoperative value of 297 ± 27 ng · kg−1 to 418 ± 106 ng · kg−1 at 60 min after declamping of the aorta (P < 0.01) but did not change in Group II. Serum S-ELAM-1 concentration did not change in either group. Serum concentration of IL-8 and IL-6 in Group I (37 ± 44 pg · kg−1, and 59 ± 59 pg · kg−1, preoperatively) increased to 169 ± 86 pg · kg−1 and 436 ± 143 pg · kg−1 at 60 min after declamping of the aorta (P < 0.001, P < 0.001). The increases were greater than those from 25 ± 6 pg · kg−1 and 30 ± 26 pg · kg−1 to 56 ± 36 pg · kg−1 and 132 ± 78 pg · kg−1 in Group II (P < 0.001, P < 0.001). The levels of S-ICAM-1 correlated with those of IL-8 (r = 0.5, P < 0.001).ConclusionThese results suggest that ulinastatin may suppress the increase in IL-8 production and the expression of ICAM-1 during cardiac surgery.RésuméObjectifRechercher si le l’administration préalable d’ulinastatin (6000 U · kg−1 avant la CEC et au déclampage de l’aorte) influençait la production de cytokines et de molécules adhésives dans la circulation périphérique.MéthodesCette étude prospective et aléatoire a été réalisée chez 22 patients soumis à une chirurgie cardiaque. Ils ont été répartis entre deux groupes. Les patients du groupe I n’ont pas reçu de l’ulinastatin alors que le groupe en a reçu. La molécule-1 adhésive intercellulaire soluble (S-1CAM-1), la molécule-1 endothéliale leucocytaire soluble (S-ALAM-1), les inlerleukines 8 et 6 (IL-8, 6) ont été mesurées à l’aide d’une trousse ELISA.RésultatsLa concentration sérique de S-ICAM-1 du groupe I a augmenté 60 min après le déclampage de l’aorte de la valeur préopératoire de 297 ± 27 ng · kg−1 à 418 ± 106 ng · kg−1 (P < 0,01) mais est demeurée inchangée dans le groupe II. La concentration sérique de IL-8 et IL-6 n’a pas changé dans les deux groupes. Les concentrations sériques de IL-8 et IL-6 dans le groupe I (valeurs préopératoires 37 ± 44 pg · kg−1 et 59 ± 59 pg · kg−1) ont a augmenté à 169 ± 86 pg · kg−1 et 436 ± 43 pg · kg−1 60 min après le déclampage de l’aorte (P < 0,001, P < 0,001). Les niveaux de S-ICAM-1 étaient en corrélation avec ceux de IL-8 (r = 0,5, P < 0,001).ConclusionCes résultats suggèrent que l’ulinastatin peut supprimer l’augmentation de la production de IL-8 et se ICAM-1.

Effects of prolonged nitrous oxide exposure on hemopoietic stem cells in splenectomized mice.

We have demonstrated in previous papers that prolonged nitrous oxide exposure suppresses murine hemopoiesis more in the spleen than in the bone marrow and that this is caused by the suppression of the hemopoietic supportive activity of the microenvironment. In the present study, we used splenectomized mice as an experimental model to investigate the direct effect on bone marrow function of prolonged nitrous oxide inhalation. All of the experimental mice were splenectomized at the age of 4 wk. Half of the experimental mice were continuously exposed to 50% nitrous oxide, and the remainder were continuously exposed to air as controls, starting 3 wk after splenectomy and lasting 14 days, and the numbers of pluripotent hemopoietic stem cells (CFU-S) and granulocyte-macrophage progenitor cells (GM-CFC) in bone marrow were counted. The numbers of pluripotent hemopoietic stem cells and granulocyte-macrophage progenitor cells in the bone marrow of mice exposed to air showed no significant change. The numbers of these two types of cells found in nitrous oxide-exposed mice were approximately 60% of control levels. These data are almost the same as our previously reported bone marrow data obtained in nonsplenectomized mice exposed to nitrous oxide for 14 days. The present results suggest that the marked decrease in the number of splenic hemopoietic stem cells in our previous data is not a result of migration of the cells to bone marrow, and that nitrous oxide directly affects murine bone marrow hemopoiesis.

Simple deep hypothermia for open heart surgery in infancy

SummaryResults of open cardiac surgery under deep simple hypothermia in 121 infants with body weight of less than 10 kg are reported. Deep ether anaesthesia combined with large quantities of ganglion blocking agents (triflupromazine 3 mg/kg) constitutes the anaesthetic management of choice for deep surface-induced hypothermia. The mean lowest oesophageal temperature was 20.8° C, and 18.9° C rectally. The mean circulatory arrest time was 40 minutes. Seventeen infants ( 14.0 per cent) died post-operatively. There were no operative deaths attributable to failure of cardiac resuscitation.This technique widens the scope of open heart surgery in small infants. Most of the surgically correctable malformations should be operable by this method. More than the potential hazards of hypothermia, which we believe are solved by our technique, the major problem posed by surgery in these small infants is the trans and post-operative respiratory management.RésuméLes auteurs rapportent leur expérience de 121 enfants de moins de 10 kilos ( poids moyen: 7.8 kilos), opérés à cœur ouvert, sous hypothermie profonde, au cours des huit dernières années. Quatre-vingt-un de ces enfants étaient de moins ďun an (âge moyen: 12.3 mois).Ces enfants ont été opérés sous C.E.C., en hypothermie profonde permettant des arrêts circulatoires de 14 à 77 minutes (moyenne: 40 minutes 20 secondes).Ľhypothermie était produite par immersion en bain ďeau glacée sous ânes thésie profonde à ľéther et sous protection de bloqueurs sympathiques à hautes doses. La moyenne des températures œsophagiennes atteintes se situait à 20.8° C, et celle des températures rectales à 18.9° C.Aucun décès n’est relié à des causes anesthésiques ou à la réanimation du myocarde. Cependant, les soins post-opératoires respiratoires ont influencé significativement le pronostic. Dix-sept enfants (14 pour cent) sont morts en post-opératoire. p ]Les auteurs concluent que ľhypothermie profonde est une méthode simple pour la chirurgie ouverte des tout jeunes enfants.

Effects of prolonged nitrous oxide exposure on hemopoietic stem cells in mice

The effects of prolonged exposure to nitrous oxide on the hemopoietic progenitor cells in bone marrow and spleen in mice were investigated. Fifty percent nitrous oxide caused a marked decrease in the number of pluripotent stem cells (CFU-S) and granulocyte-macrophage progenitor cells (GM-CFC) in the spleen, whereas it caused only a slight decrease in these cells in the bone marrow. These results suggest that prolonged exposure to nitrous oxide induces damage in the splenic hemopoiesis in mice.

Prolonged nitrous oxide exposure inhibits settlement of transplanted hemopoietic stem cells in murine spleen.

In order to clarify the mechanism of hemopoietic depression induced by nitrous oxide inhalation, effects of prolonged nitrous oxide exposure on the settlement of transplanted bone marrow cells were investigated. Mice were continuously exposed to mixed gas containig 50% nitrous oxide, 21% oxygen and 29% nitrogen for 7 days and then they were irradiated with 850 rads, By the irradiation, endogenous pluripotent hemopoietic stem cells (CFU-S) almost disappeared in the mice. Normal syngenic murine bone marrow cells were injected intravenously and the numbers of CFU-S, which settled in the bone marrow and spleen 2 hr after injection, were measured. There was no difference of the numbers of CFU-S settled in the bone marrow between nitrous oxide and control gas exposed mice. In contrast, the numbers of CFU-S in the spleen of nitrous oxide exposed mice were approximately 60% of the control. These results and our previous data suggest that hemopoietic inhibitory effects of nitrous oxide in mice are due to a damage of splenic hemopoietic microenvironment, that supports the settlement of hemopoietic stem cells.