Relationship between respiratory distress and cytokine response after cardiopulmonary bypass

Inflammation and Oxidative Stress in the Context of Extracorporeal Cardiac and Pulmonary Support

Extracorporeal circulation (ECC) systems, including cardiopulmonary bypass, and extracorporeal membrane oxygenation have been an irreplaceable part of the cardiothoracic surgeries, and treatment of critically ill patients with respiratory and/or cardiac failure for more than half a century. During the recent decades, the concept of extracorporeal circulation has been extended to isolated machine perfusion of the donor organ including thoracic organs (ex-situ organ perfusion, ESOP) as a method for dynamic, semi-physiologic preservation, and potential improvement of the donor organs. The extracorporeal life support systems (ECLS) have been lifesaving and facilitating complex cardiothoracic surgeries, and the ESOP technology has the potential to increase the number of the transplantable donor organs, and to improve the outcomes of transplantation. However, these artificial circulation systems in general have been associated with activation of the inflammatory and oxidative stress responses in patients and/or in the exposed tissues and organs. The activation of these responses can negatively affect patient outcomes in ECLS, and may as well jeopardize the reliability of the organ viability assessment, and the outcomes of thoracic organ preservation and transplantation in ESOP. Both ECLS and ESOP consist of artificial circuit materials and components, which play a key role in the induction of these responses. However, while ECLS can lead to systemic inflammatory and oxidative stress responses negatively affecting various organs/systems of the body, in ESOP, the absence of the organs that play an important role in oxidant scavenging/antioxidative replenishment of the body, such as liver, may make the perfused organ more susceptible to inflammation and oxidative stress during extracorporeal circulation. In the present manuscript, we will review the activation of the inflammatory and oxidative stress responses during ECLP and ESOP, mechanisms involved, clinical implications, and the interventions for attenuating these responses in ECC.

Effect of 6% Hydroxyethyl Starch 130/0.4 on Inflammatory Response and Pulmonary Function in Patients Having Cardiac Surgery: A Randomized Clinical Trial

BACKGROUND

Cardiac surgery with cardiopulmonary bypass induces a profound inflammatory response that, when severe, can lead to multiorgan system dysfunction. Preliminary data suggest that administration of hydroxyethyl starch (HES) solutions may mitigate an inflammatory response and improve pulmonary function. Our goal was to examine the effect of 6% HES 130/0.4 versus 5% human albumin given for intravascular plasma volume replacement on the perioperative inflammatory response and pulmonary function in patients undergoing cardiac surgery.

METHODS

This was a subinvestigation of a blinded, parallel-group, randomized clinical trial of patients undergoing elective aortic valve replacement surgery at the Cleveland Clinic main campus, titled "Effect of 6% Hydroxyethyl Starch 130/0.4 on Kidney and Haemostatic Function in Cardiac Surgical Patients." Of 141 patients who were randomized to receive either 6% HES 130/0.4 or 5% human albumin for intraoperative plasma volume replacement, 135 patients were included in the data analysis (HES n = 66, albumin n = 69). We assessed the cardiopulmonary bypass-induced inflammatory response end points by comparing the 2 groups' serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and macrophage migration inhibitory factor (MIF), measured at baseline and at 1 and 24 hours after surgery. We also compared the 2 groups' postoperative pulmonary function end points, including the ratio of partial pressure of arterial oxygen to fraction of inspired oxygen (Pao2:Fio2 ratio), dynamic lung compliance, oxygenation index (OI), and ventilation index (VI) at baseline, within 1 hour of arrival to the intensive care unit, and before tracheal extubation. The differences in the postoperative levels of inflammatory response and pulmonary function between the HES and albumin groups were assessed individually in linear mixed models.

RESULTS

Serum concentrations of the inflammatory markers (TNF-α, IL-6, MIF) were not significantly different (P ≥ .05) between patients who received 6% HES 130/0.4 or 5% albumin, and there was no significant heterogeneity of the estimated treatment effect over time (P ≥ .15). The results of pulmonary function parameters (Pao2:Fio2 ratio, dynamic compliance, OI, VI) were not significantly different (P ≥ .05) between groups, and there was no significant heterogeneity of the estimated treatment effect over time (P ≥ .15).

CONCLUSIONS

Our investigation found no significant difference in the concentrations of inflammatory markers and measures of pulmonary function between cardiac surgical patients who received 6% HES 130/0.4 versus 5% albumin.

Autotransfusion during Extracorporeal Membrane Oxygenation

To reduce allogeneic blood transfusion requirements during extracorporeal membrane oxygenation (ECMO) we evaluated an autotransfusion device which processes and retransfuses erythrocytes of changed ECMO-systems. We studied 10 elective changes of ECMO-systems in 7 patients. Hemoglobin levels, the amount of retransfused autologous blood and of transfused allogeneic packed red blood cell units were documented within 48 h after the system change and compared to the measurements obtained from former ECMO-system changes without using any autotransfusion device. We determined the Horrowitz-index, Interleukin 6, 10, TNF-α and endothelin-I concentrations and coagulation parameters during the 48 hours after system change to study the compatibility of this procedure. Allogeneic blood transfusion was reduced from 7 to 2 units of packed red cells using the autotransfusion device. Additionally, no hints of any harmful side effects in these patients was observed.

High-dose ulinastatin improves postoperative oxygenation in patients undergoing aortic valve surgery with cardiopulmonary bypass: A retrospective study

Objective

To determine whether pre-treatment with high-dose ulinastatin provides enhanced postoperative oxygenation in patients who have undergone aortic valve surgery with moderate hypothermic cardiopulmonary bypass (CPB).

Methods

Patients who underwent aortic valve surgery with moderate hypothermic CPB were retrospectively evaluated. In total, 94 of 146 patients were included. The patients were classified into one of two groups: patients in whom ulinastatin (10,000 U/kg followed by 5,000 U/kg/h) was administered during CPB (Group U, n = 38) and patients in whom ulinastatin was not administered (Group C, n = 56). The PaO₂/FiO₂ ratio was calculated at the following time points: before CPB (pre-CPB), 2 h after weaning from CPB (post-CPB), and 6 h after arrival to the intensive care unit (ICU-6). The incidence of a low PaO₂/FiO₂ ratio was also compared among the time points.

Results

Group U showed a significantly higher PaO₂/FiO₂ ratio (F(4, 89.0) = 657.339) and a lower incidence of lung injury (PaO₂/FiO₂ ratio < 300) than Group C at the post-CPB and ICU-6 time points.

Conclusion

High-dose ulinastatin improved pulmonary oxygenation after CPB and in the early stages of the ICU stay in patients undergoing aortic valve surgery with CPB.

Investigating the Impacts of Preoperative Steroid Treatment on Tumor Necrosis Factor-Alpha and Duration of Extubation Time underwent Ventricular Septal Defect Surgery

BACKGROUND

Cardiopulmonary bypass is known to cause inflammatory events. Inflammation occurs due to many known important biological processes. Numerous mechanisms are known to be responsible for the development of inflammatory processes. Currently, there are many defined mediators as a tumor necrosis factor-α (TNF-α) playing an active role in this process.

AIMS

This research was to investigate the effects of pre-operative steroid use on inflammatory mediator TNF-α and on time to extubation postoperatively in ventricular septal defect patients undergoing cardiopulmonary bypass surgery.

STUDY DESIGN

Controlled clinical study.

METHODS

This study included 30 patients. These patients were assigned into two groups, each containing 15 patients. 5 micrograms/kg methylprednisolone was injected intravenously 2 hours before the surgery to Group I, whereas there was no application to the patients in Group II. TNF-α (pg/mL) level was measured in arterial blood samples obtained at four periods including: the preoperative period (Pre TNF); at the 5(th) minute of cross-clamping (Per TNF); 2 hours after termination of cardiopulmonary bypass (Post TNF); and at the postoperative 24th hours in cardiovascular surgery intensive care unit (Post 24 h TNF).

RESULTS

The mean cross-clamp time was 66±40 and 55±27 minutes in Group I and Group II respectively. No significant difference was found between the groups in terms of cross-clamp time (p>0.05). The mean time to extubation was 6.1±2.3 hours in Group I and 10.6±3.4 hours in Group II. Group I extubation time was significantly shorter than Group II. Group I TNF-α levels at Post TNF and Post24h TNF was lower than Group II. These differences are also statistically significant (p<0.05).

CONCLUSION

There is a strong indication that preoperative steroid treatment reduced the TNF-α level together with shortens duration of postoperative intubation and positively contributes to extubation in ventricular septal defect patients operated in cardiac surgery with cardiopulmonary bypass. (ClinicalTrials.gov Identifier: TCTR20150930001).

Management and postoperative outcome in primary lung cancer and heart disease co-morbidity: a systematic review and meta-analysis

BACKGROUND

Co-morbidity of primary lung cancer (LC) and heart disease (HD), both requiring surgical therapy, characterizes a high risk group of patients necessitating prompt diagnosis and treatment. The aim of this study is the review of available evidence guiding the management of these patients.

METHODS

Postoperative outcome of patients operated for primary LC (first meta-analysis) and for both primary LC and HD co-morbidity (second meta-analysis), were studied. Parameters examined in both meta-analyses were thirty-day postoperative mortality, postoperative complications, three- and five-year survival probabilities. The last 36 years were reviewed by using the PubMed data base. Thirty-seven studies were qualified for both meta-analyses.

RESULTS

The pooled 30-day mortality percentages (%) were 4.16% [95% confidence interval (CI): 2.68-5.95] (first meta-analysis) and 5.26% (95% CI: 3.47-7.62) (second meta-analysis). Higher percentages of squamous histology and lobectomy, were significantly associated with increased (P=0.001) and decreased (P<0.001) thirty-day postoperative mortality, respectively (first meta-analysis). The pooled percentages for postoperative complications were 34.32% (95% CI: 24.59-44.75) (first meta-analysis) and 45.59% (95% CI: 35.62-55.74) (second meta-analysis). Higher percentages of squamous histology (P=0.001), lobectomy (P=0.002) and p-T1 or p-T2 (P=0.034) were associated with higher proportions of postoperative complications (second meta-analysis). The pooled three- and five- year survival probabilities were 68.25% (95% CI: 45.93-86.86) and 52.03% (95% CI: 34.71-69.11), respectively. Higher mean age (P=0.046) and percentage lobectomy (P=0.009) significantly reduced the five-year survival probability.

CONCLUSIONS

Lobectomy and age were both accompanied by reduced five-year survival rate. Also, combined aorto-coronary bypass grafting (CABG) with lobectomy for squamous pT1 or pT2 LC displayed a higher risk of postoperative complications. Moreover, medical decision between combined or staged surgery is suggested to be individualized based on adequacy of coronary arterial perfusion, age, patient's preoperative performance status (taking into account possible co-morbidities per patient), tumor's staging and extent of lung resection.

Ultrasonography and Lung Mechanics Can Diagnose Diaphragmatic Paralysis Quickly

Diaphragmatic paralysis after cardiovascular surgery requires early diagnosis prior to extubation. The effectiveness of ultrasonography and a lung mechanics assessment was evaluated. Paralysis of the diaphragm was diagnosed when the diaphragm failed to move or moved in a cephalad direction during inspiration. It was diagnosed in 3 of 40 patients (7.5%) who underwent cardiovascular surgery from 1998 to 1999. Patients were extubated when all parameters met the extubation criteria, irrespective of the presence or absence of diaphragmatic paralysis. One patient required prolonged assisted ventilation and died from mediastinitis on the 35th postoperative day. The other 2 patients required assisted ventilation for an additional 1–3 days. Ultrasonography and a lung mechanics assessment are effective tools for the early diagnosis of diaphragmatic paralysis and assessment of respiratory function after cardiovascular surgery.

Effect of ulinastatin on perioperative organ function and systemic inflammatory reaction during cardiac surgery: a randomized double-blinded study

BACKGROUND

This study evaluated the efficacy of ulinastatin for attenuating organ injury and the release of proinflammatory cytokines due to cardiopulmonary bypass (CPB) during cardiac surgery.

METHODS

Patients undergoing valvular heart surgery employing CPB were assigned to receive either ulinastatin (group U, n = 13) or a placebo (group C, n = 11) before the commencement of CPB. Hemodynamic data, parameters of major organ injury and function, and proinflammatory cytokines were measured after the induction of anesthesia (T1), after CPB (T2), at the end of anesthesia (T3), and at 24 hours after surgery (POD).

RESULTS

The demographic data, CPB duration, and perioperative transfusions were not different between the groups. PaO2/FiO2 in group U was significantly higher than that in group C at T3 (3.8 ± 0.8 vs. 2.8 ± 0.7, P = 0.005) and at POD (4.0 ± 0.7 vs. 2.8 ± 0.7, P < 0.001). Creatine kinase-MB at POD in group U was significantly lower than that in group C (17.7 ± 8.3 vs. 33.7 ± 22.1, P = 0.03), whereas troponin I at POD was not different between the groups. Creatinine clearance and the extubation time were not different between the groups at POD. The dopamine infusion rate during the post-CPB period in group U was significantly lower than that in group C (1.6 ± 1.6 vs. 5.5 ± 3.3 µg/kg/min, P = 0.003). The interleukin-6 and tumor necrosis factor-α concentrations at T1, T2, and T3 as well as the incidences of postoperative cardiac, pulmonary and kidney injuries were not different between the groups.

CONCLUSIONS

Ulinastatin pretreatment resulted in an improved oxygenation profile and reduced inotropic support, probably by attenuating the degree of cardiopulmonary injury; however, it did not reduce the levels of proinflammatory cytokines.

Protective effects of inhaled carbon monoxide in pig lungs during cardiopulmonary bypass are mediated via an induction of the heat shock response

BACKGROUND

Cardiopulmonary bypass (CPB) may cause acute lung injury leading to increased morbidity and mortality after cardiac surgery. Preconditioning by inhaled carbon monoxide reduces pulmonary inflammation during CPB. We hypothesized that inhaled carbon monoxide mediates its anti-inflammatory and cytoprotective effects during CPB via induction of pulmonary heat shock proteins (Hsps).

METHODS

Pigs were randomized either to a control group, to standard CPB, to carbon monoxide+CPB, or to quercetin (a flavonoid and unspecific inhibitor of the heat shock response)+control, to quercetin+CPB, and to quercetin+carbon monoxide+CPB. In the carbon monoxide groups, lungs were ventilated with 250 ppm carbon monoxide in addition to standard ventilation before CPB. At various time points, lung biopsies were obtained and pulmonary Hsp and cytokine concentrations determined.

RESULTS

Haemodynamic parameters were largely unaffected by CPB, carbon monoxide inhalation, or administration of quercetin. Compared with standard CPB, carbon monoxide inhalation significantly increased the pulmonary expression of the Hsps 70 [27 (SD 3) vs 69 (10) ng ml(-1) at 120 min post-CPB, P<0.05] and 90 [0.3 (0.03) vs 0.52 (0.05) after 120 min CPB, P<0.05], induced the DNA binding of heat shock factor-1, reduced interleukin-6 protein expression [936 (75) vs 320 (138) at 120 min post-CPB, P<0.001], and decreased CPB-associated lung injury (assessed by lung biopsy). These carbon monoxide-mediated effects were inhibited by quercetin.

CONCLUSIONS

As quercetin, a Hsp inhibitor, reversed carbon monoxide-mediated pulmonary effects, we conclude that the anti-inflammatory and protective effects of preconditioning by inhaled carbon monoxide during CPB in pigs are mediated by an activation of the heat shock response.

Activation of a Neutrophil-Derived Inflammatory Response in the Airways During Cardiopulmonary Bypass

Cardiopulmonary bypass (CPB) is believed to cause postoperative lung dysfunction. To more closely examine the inflammatory processes occurring in the airways during CPB, we serially measured inflammatory mediators, with the assistance of a new bronchoscopic microsample probe, in 11 patients undergoing repair of aortic arch aneurysms. Epithelial lining fluid (ELF) and arterial blood were sampled simultaneously after induction of anesthesia, at the time of pulmonary reperfusion, and at the end of surgery. A decrease in the PaO2/FiO2 ratio was observed at the end of surgery (P = 0.029). Although the ELF concentrations of interleukin (IL)-8, IL-6, and neutrophil elastase had increased significantly at the end of surgery (median = 23,200, 1818, and 12,900 microg/mL, respectively), they did not correlate with the degree of hypoxemia. Neutrophil elastase increased significantly at the time of pulmonary reperfusion, before IL-8 and IL-6, and independently of blood transfusions. At the end of surgery, IL-6 in ELF correlated with total blood transfusion volume (rho = 0.731, P = 0.011). These results indicate that a neutrophil-derived inflammatory response is activated in the airway in the early phase of CPB.

Effect of a Polymorphonuclear Elastase Inhibitor (Sivelestat Sodium) on Acute Lung Injury After Cardiopulmonary Bypass: Findings of a Double-Blind Randomized Study

PURPOSE

We evaluated the effect of sivelestat sodium (SiV), a novel synthesized polymorphonuclear (PMN) elastase inhibitor, on acute lung injury (ALI) caused by cardiopulmonary bypass (CPB).

METHODS

Fourteen patients who underwent cardiopulmonary surgery using CPB, followed by the development of both systemic inflammatory response syndrome (SIRS) and ALI, were treated with either 0.2 mg/kg per hour SiV (SiV group, n = 7) or saline (control group, n = 7) for 4 days from the time of arrival in the intensive care unit.

RESULTS

The SiV group had a significantly lower ratio of serum PMN elastase and interleukin (IL)-8, a significantly lower ratio of the respiratory index, and a significantly higher ratio of PaO(2)/FiO(2) after 24 h of treatment than the control group.

CONCLUSION

Sivelestat sodium suppressed the production of PMN elastase and IL-8, resulting in improved respiratory function in patients with ALI caused by CPB.

Gender-Specific Differences in Sex Hormones and Cytokines in Patients Undergoing Major Abdominal Surgery

PURPOSE

Experimental and clinical evidence suggests that gender has a profound influence on outcome after inflammatory hits caused by such events as trauma. We conducted this prospective clinical study to evaluate the influence of gender on the release of pro- and anti-inflammatory cytokines in the circulation and after lipopolysaccharide (LPS) ex vivo stimulation. We also measured the course of sex hormones in the acute phase response after surgery and assessed their correlation with cytokine release.

METHODS

We measured the serum concentrations of interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-alpha (TNF-alpha), testosterone, estradiol, prolactin, procalcitonin, and sex hormone-binding globulin, as well as the release of IL-6, TNF-alpha, and IL-10 after LPS ex vivo stimulation of whole blood in 26 patients without complications after major or minor abdominal surgery.

RESULTS

There was a gender-specific pattern of decreasing testosterone concentrations in men and increasing testosterone concentrations in women. Increasing estradiol concentrations were seen in both men and women. The ex vivo-stimulated and systemic IL-6, IL-8, IL-10, and TNF-alpha cytokine release was not gender specific. There was a marked prolactin peak after the induction of anesthesia before the commencement of surgery.

CONCLUSION

In contrast to the release of pro- and anti-inflammatory cytokines, sex hormones show a gender-specific pattern during the acute phase response 1 week after abdominal surgery.

The effect of intravenous quinaprilat on plasma cytokines and hemodynamic variables during cardiac surgery

OBJECTIVES

Perioperative treatment with angiotensin-converting enzyme (ACE) inhibitors in cardiac surgery with cardiopulmonary bypass is still controversial. Using ACE inhibitors during cardiac surgery might be associated with an increased risk of critical hypotensive episodes. On the other hand, ACE inhibitors could have beneficial effects with respect to the development of the systemic inflammatory response syndrome.

DESIGN

The effect of acute administration of quinaprilat on hemodynamic variables and plasma cytokines was assessed under double-blind, randomized, and placebo-controlled conditions.

SETTING

Department of anesthesiology and cardiovascular surgery clinic in a university hospital.

PARTICIPANTS

Forty patients without preexisting cardiac failure, undergoing coronary artery bypass grafting.

INTERVENTIONS

Patients received 0.08 mg/kg of intravenous quinaprilat or intravenous isotonic saline solution after induction of anesthesia.

MEASUREMENTS AND RESULTS

Blood samples were taken after induction of anesthesia (T0), before cardiopulmonary bypass (T1), at the end of surgery (T2), and 4 hours after the end of surgery (T3). There was no difference between the 2 groups regarding mean arterial pressure and inotropic or vasopressor support. Systemic vascular resistance index was significantly lower in the quinaprilat group at T2 (p = 0.016) and T3 (p = 0.017). No difference in proinflammatory cytokine levels was observed between the 2 groups.

CONCLUSIONS

The present investigation shows that acute administration of an intravenous ACE inhibitor, quinaprilat, has no influence on proinflammatory cytokines during cardiac surgery with cardiopulmonary bypass. The patients treated with quinaprilat showed an improved systemic vascular resistance index with no increased risk of deleterious hemodynamic episodes.

Tumor necrosis factor and clinical and metabolic courses after cardiac surgery in children

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.

Inflammation After Cardiopulmonary Bypass: Therapy for the Postpump Syndrome

Cardiopulmonary bypass (CPB) is used in most, but not all, complex heart operations. CPB is associated with a systemic inflammatory response in adults and children. Many materials-dependent (exposure of blood to non- physiologic surfaces and conditions) and materials-in dependent (surgical trauma, ischemia-perfusion to the organs, changes in body temperature, and release of endotoxin) factors during CPB have been implicated in the etiology of this complex response. The mechanisms involved may include complement activation, release of cytokines, leukocyte activation with expression of ad hesion molecules, and production of various vasoactive and immunoactive substances. Postpump inflamma tion may lead to postoperative complications and may result in respiratory failure, renal dysfunction, bleeding disorders, neurologic dysfunction, altered liver func tion, and ultimately multiple organ failure. Significant efforts are being made to decrease the generation and effects of postpump inflammation. Interventions to this end have included avoiding CPB when possible, im proving the biocompatibility of the involved mechani cal devices, and administering medications that main tain cellular integrity. This article provides an overview of the etiology, pathophysiology, and treatment of postpump inflammation. Perhaps with additional in sight into this syndrome, CPB can be made a safer and more efficacious modality of cardiorespiratory support. Copyright© 2001 by W.B. Saunders Company.

Clinical efficacy of heparin-bonded bypass circuits related to cytokine responses in children

BACKGROUND

Cardiopulmonary bypass (CPB) induces numerous systemic reactions. This study examined the efficacy of heparin-bonded CPB circuits on inflammatory responses and postoperative status in children.

METHODS

Thirty-four infants undergoing elective cardiac surgery were randomly divided into two groups: a heparin-bonded CPB group (n = 17) and a non-heparin-bonded group (n = 17). Plasma levels of the inflammatory cytokines were measured before, during, and after CPB, and postoperative status was determined by examining the respiratory index, blood loss, and the post- and preoperative body weight percent ratio.

RESULTS

Significant differences in tumor necrosis factor-alpha, interleukin-6, and interleukin-8 patterns were observed during and after CPB between the two groups (p < 0.01, p < 0.01, p < 0.05, respectively). All cytokines measured were significantly lower in the heparin-bonded group just after CPB (p < 0.05). There were no differences in duration of intubation, intensive care unit or hospital stay, or postoperative blood loss, but the respiratory index 3 hours after CPB and body weight percent ratio 24 and 48 hours after CPB were significantly reduced in the bonded group (p < 0.05, p < 0.01, p < 0.05, respectively).

CONCLUSIONS

Our findings suggest that heparin bonding of the bypass circuits affects early postoperative status and reduces cytokine responses in pediatric cardiac surgery.

The effects of circulating interleukin-8 and adhesion molecules on pulmonary dysfunction in pediatric orthotopic liver transplantation

We investigated the effects of circulating inflammatory cytokines and adhesion molecules induced by ortho-topic liver transplantation (OLT) on pulmonary function. Although the plasma interleukin-8 (IL-8) levels increased gradually, peaking at the end of the operation, these increases were considered minimal. The baseline endothelial adhesion molecule (E-selectin) level was several times higher than the normal value, but after reperfusion of the new transplanted liver, the plasma E-selectin concentrations decreased to within the normal range and remained almost normal during the postoperative period. Similar changes were observed in the plasma levels of other types of adhesion molecules. Although PaO(2)/FIO(2) showed a significant inversed correlation with the peak IL-8 concentration, after the exclusion of two patients, one of whom died and one of whom rejected the transplanted liver, no correlation was able to be found between the PaO(2)/FIO(2) ratio and the maximum IL-8 concentration. Furthermore, there was no correlation between the adhesion moleclues and PaO(2)/FIO(2). These results suggest that IL-8 exerts only a slight effect on respiratory function following successful pediatric liver transplantation, and that circulating adhesion molecules do not affect perioperative lung function.

Protective effects of ONO-5046*Na, a specific neutrophil elastase inhibitor, on postperfusion lung injury

BACKGROUND

Polymorphonuclear neutrophil elastase might contribute to postperfusion lung injury, so we evaluated the protective effect of ONO-5046*Na, a specific inhibitor of polymorphonuclear neutrophil elastase, against such an injury.

METHODS

The study was done using 8 mongrel dogs that received ONO-5046*Na (15 mg/kg per hour) (group O) and 8 control dogs (group C), all of which had 1 hour of partial bypass and 5 hours of observation.

RESULTS

The respiratory index showed no significant changes in group O, but increased significant in group C (1.4+/-2.0 versus 5.1+/-4.7, p = 0.0047). Pulmonary extravascular water volume increased markedly in group C but only slightly in group O (group C 20.6+/-8.7, group O 11.2+/- 2.7 mL/kg; p = 0.0005). Blood concentrations of polymorphonuclear neutrophil elastase and interleukin-6 showed more than a tenfold increase in group C (PMN elastase, group C 12.9+/-12.8, group O 2.4+/-1.3 ng/mL; IL-b, group C 11.0+/-9.3, group O 2.9+/-3.8 pg/mL; p < 0.05) but were only slightly higher in group O. Histologic examination revealed interstitial and intraalveolar edema in group C, but group O was virtually normal.

CONCLUSIONS

ONO-5046*Na inhibits polymorphonuclear neutrophil elastase and maintains better pulmonary function, so it should reduce postperfusion lung injury.

IL-6 and IL-8 levels after cardiopulmonary bypass are not affected by surface coating

BACKGROUND.:Contact of blood with the surfaces of the cardiopulmonary bypass (CPB) circuit has been implicated as a cause of the inflammatory response. We undertook a prospective randomized trial of 200 pediatric patients, all with a calculated total bypass flow of less than 2.3 L/min (< 0.96 L/m2/min).

METHODS

Patients were randomly assigned to 1 of 4 CPB groups: (1) Nonheparin-bonded circuit with no albumin preprime; (2) Nonheparin-bonded circuit with albumin preprime; (3) Heparin-bonded circuit with no albumin preprime; (4) Heparin-bonded circuit with albumin preprime. Measurements of cytokines, (interleukin [IL]-6, IL-8) and blood cell counts were made prebypass and 6 and 24 hours after institution of cardiopulmonary bypass.

RESULTS

Analysis of variance showed no significant difference in any of the clinical or biochemical characteristics of the 4 groups. The interaction between heparin-bonded oxygenators and albumin preprime was not significant. No important differences in IL-6 or IL-8 concentrations were noted after CPB using either heparin or nonheparin-bonded oxygenators with albumin or albumin free preprime using two-way analysis of variance.

CONCLUSIONS

Albumin preprime and heparin-bonding do not attenuate the inflammatory response component attributable to the concentration of these markers.

The balance of pro- and anti-inflammatory cytokines in cardiac surgery

Homeostatic control of the balance of pro- and anti-inflammatory cytokines is important for the maintenance of health. Cardiac surgery, with its intense pro-inflammatory stimulus, constitutes a major challenge to the patient's ability to maintain this balance. Pre- and intraoperative factors influencing the maintenance of cytokine balance are discussed.