Obesity is associated with increased morbidity after coronary artery bypass graft surgery in patients with renal insufficiency

OBJECTIVE

Although obesity is a major risk factor for cardiovascular disease, it is not clear whether obesity increases the risk of postoperative morbidity and mortality in patients undergoing coronary artery bypass grafting surgery. Increasing evidence suggests that both obesity and renal insufficiency are associated with increased systemic inflammation, thrombogenicity, and endothelial dysfunction. Cardiac surgical patients with comorbid obesity and renal insufficiency might thus be at greater risk for systemic proinflammatory and thrombotic states, which in turn might increase the risk of adverse perioperative outcomes. We investigated the influence of obesity on adverse postoperative outcomes after coronary artery bypass grafting surgery in patients with and without renal insufficiency.

METHODS

A retrospective cohort study was performed of patients (n = 10,863) undergoing primary coronary artery bypass grafting surgery with cardiopulmonary bypass between January 1995 and June 2005. Patients with preoperative renal insufficiency (n = 1385) and patients with preoperative normal renal function (n = 9478) were further classified as obese (body mass index, > or =30 kg/m(2)) or nonobese (body mass index, 18.5-29.9 kg/m(2)). Multivariate, stepwise logistic regression was performed, controlling for demographic factors, medications, and perioperative risk factors to determine whether obesity is independently associated with an increased risk of adverse postoperative outcomes after coronary artery bypass grafting surgery in patients with or without renal insufficiency.

RESULTS

Obese patients with preoperative renal insufficiency had higher rates of postoperative myocardial infarction (5.9% vs 3.4%) and low cardiac output syndrome (24.5% vs 18.6%) and increased hospital stay (14.9 +/- 13.7 vs 13.2 +/- 13.0 days) than nonobese patients with preoperative renal insufficiency (all outcomes, P < .05). Multivariate analysis revealed that obese patients with preoperative renal insufficiency were independently associated with an increased risk of postoperative myocardial infarction (odds ratio, 1.82; 95% confidence interval, 1.07-3.07; P < .05) and low cardiac output syndrome (odds ratio, 1.53; 95% confidence interval, 1.15-2.03; P < .01) and increased hospital stay (P < .05). In contrast, obese patients with normal preoperative renal function were independently associated only with an increased risk of postoperative sternal wound infection (odds ratio, 2.55; 95% confidence interval, 1.40-4.67; P < .01) and leg wound infection (odds ratio, 2.27; 95% confidence interval, 1.71-3.02; P < .01).

CONCLUSION

Obesity is an independent risk factor for increased cardiovascular morbidity and prolonged hospital stay in patients with preoperative renal insufficiency undergoing primary coronary artery bypass grafting surgery.

Preoperative B-type natriuretic peptide is as independent predictor of ventricular dysfunction and mortality after primary coronary artery bypass grafting

OBJECTIVE

Elevated B-type natriuretic peptide is associated with increased morbidity and mortality in ambulatory patients with congestive heart failure or acute coronary syndromes. Its utility in predicting adverse cardiac surgical outcomes is less certain. We hypothesized that preoperative plasma B-type natriuretic peptide would independently predict in-hospital postoperative ventricular dysfunction, hospital stay, and up to 5-year mortality after primary coronary artery bypass grafting.

METHODS

This is a prospective, longitudinal study of 1023 patients at two institutions undergoing primary coronary artery bypass grafting with cardiopulmonary bypass. Ventricular dysfunction was defined as requirement for at least two inotropes or new intra-aortic balloon pump or ventricular assist device support after coronary artery bypass grafting. Multivariable analyses assessed independent roles of preoperative B-type natriuretic peptide in predicting postoperative ventricular dysfunction, hospital stay, and 5-year all-cause mortality.

RESULTS

Preoperative plasma B-type natriuretic peptide concentration predicted ventricular dysfunction, hospital stay, and mortality in univariate and multivariable analyses. Logistic regression demonstrated preoperative B-type natriuretic peptide to independently predict ventricular dysfunction (odds ratio 1.92, 95% confidence interval 1.12-3.29, P = .018), after adjustment for preoperative left ventricular ejection fraction, congestive heart failure severity, and other clinical predictors. Multivariable Cox proportional hazards models showed preoperative B-type natriuretic peptide to independently predict hospital stay (hazard ratio 1.42, 95% confidence interval 1.18-1.72, P = .0002) and mortality (hazard ratio 1.89, 95% confidence interval 1.08-3.33, P = .026).

CONCLUSION

Preoperative plasma B-type natriuretic peptide independently predicted in-hospital ventricular dysfunction, hospital stay, and up to 5-year all-cause mortality after primary coronary artery bypass grafting.

The MBL2 'LYQA secretor' haplotype is an independent predictor of postoperative myocardial infarction in whites undergoing coronary artery bypass graft surgery

BACKGROUND

Mannose-binding lectin (MBL) is an important component of innate immunity and activator of the lectin complement pathway. Within the MBL2 gene are seven 5' "secretor" haplotypes that code for altered serum MBL levels and complement activation. However, recent evidence suggests that 3' MBL2 haplotypes may also modify MBL function and circulating levels. Because MBL and the lectin complement pathway have been implicated in cardiovascular injury, we investigated whether MBL2 haplotypes are independently associated with an increased risk of postoperative myocardial infarction (PMI) in patients undergoing coronary artery bypass graft surgery.

METHODS AND RESULTS

Genotyping of 18 polymorphic sites within the MBL2 gene was performed in a prospective, longitudinal multi-institutional study of 978 patients undergoing primary coronary artery bypass graft-only surgery with cardiopulmonary bypass between August 2001 and May 2005. After adjustment for multiple comparisons by permutation testing, multivariate, stepwise logistic regression, including a score test, was performed controlling for patient demographics, preoperative risk factors, medications, and intraoperative variables to determine if MBL2 secretor haplotypes are independent predictors of PMI in whites undergoing primary coronary artery bypass graft surgery. Neither the 5' nor 3' MBL2 haplotypes alone were associated with an increased incidence of PMI. However, the incidence of PMI in whites (n=843) expressing the combined MBL2 5' LYQA secretor haplotype (CGTCGG) and 3' haplotype (CGGGT) was significantly higher than in whites not expressing the haplotype (38% versus 10%; P<0.007). Moreover, the combined MBL2 LYQA secretor haplotype was an independent predictor of PMI in whites after primary coronary artery bypass graft surgery after adjustment for other covariates (P<0.02; adjusted OR: 3.97; 95% CI: 1.30 to 12.07). The combined MBL2 LYQA secretor haplotype in whites was also an independent predictor of postoperative CKMB levels exceeding 60 ng/mL (P<0.02; adjusted OR: 4.48; 95% CI: 1.95 to 16.80). Inclusion of the combined MBL2 LYQA secretor haplotype improved prediction models for PMI based on traditional risk factors alone (C-statistic 0.715 versus 0.705).

CONCLUSIONS

The combined MBL2 LYQA secretor haplotype is a novel independent predictor of PMI and may aid in preoperative risk stratification of whites undergoing primary coronary artery bypass graft surgery.

Fluorochrome-linked immunoassay for functional analysis of the mannose binding lectin complement pathway to the level of C3 cleavage

The humoral response to invading pathogens is mediated by a repertoire of innate immune molecules and receptors able to recognize pathogen-associated molecular patterns. Mannose binding lectin (MBL) and ficolins are initiation molecules of the lectin complement pathway (LCP) that bridge innate and adaptive immunity. Activation of the MBL-dependent lectin pathway, to the level of C3 cleavage, requires functional MASP-2, C2, C4 and C3, all of which have been identified with genetic polymorphisms that can affect protein concentration and function. Current assays for MBL and MASP-2 lack the ability to assess activation of all components to the level of C3 cleavage in a single assay platform. We developed a novel, low volume, fluorochrome linked immunoassay (FLISA) that quantitatively assesses the functional status of MBL, MASP-2 and C3 convertase in a single well. The assay can be used with plasma or serum. Multiple freeze/thaw cycles of serum do not significantly alter the assay, making it ideal for high throughput of large sample databases with minimal volume use. The FLISA can be used potentially to identify specific human disease correlations between these components and clinical outcomes in already established databases.

Non-antiarrhythmic agents for prevention of postoperative atrial fibrillation: role of statins

PURPOSE OF REVIEW

Atrial fibrillation is the most common arrhythmia following cardiac surgery, having both serious medical and socioeconomic consequences. Although there are established antiarrhythmic agents for preventing and treating postoperative atrial fibrillation, these therapies are neither 100% reliable, nor without risks and limitations. Thus, there remains a strong need for non-antiarrhythmic, adjunctive therapies for the prevention of postoperative atrial fibrillation.

RECENT FINDINGS

Long-term statin administration in ambulatory patients is associated with a reduced risk of adverse cardiovascular events, including death, myocardial infarction, stroke, renal dysfunction and atrial fibrillation. Recent evidence suggests, however, that statins may also reduce the risk of acute adverse outcomes following invasive procedures, including postoperative atrial fibrillation. Although the exact mechanisms by which statins may reduce postoperative atrial fibrillation are unclear, accumulating evidence suggests that statins exert multiple effects independent of their effect on LDL cholesterol. For example, in patients with acute coronary syndromes, statin therapy has been shown to modulate remodeling of the cardiac extracellular matrix and to reduce markers of inflammation, including C-reactive protein, serum amyloid A, tumor necrosis factor-alpha, and IL-6.

SUMMARY

Perioperative statin therapy may represent an important non-antiarrhythmic, adjunctive therapeutic strategy for the prevention of postoperative atrial fibrillation.

A Phase II, Double-Blind, Placebo-Controlled, Ascending-Dose Study of Eritoran (E5564), a Lipid A Antagonist, in Patients Undergoing Cardiac Surgery with Cardiopulmonary Bypass

BACKGROUND

Lipid A, the toxic moiety of endotoxin, is linked to multiple complications after cardiac surgery, including fever, vasodilation, and pulmonary and renal dysfunction. The lipid A antagonist eritoran (or E5564) prevents endotoxin-induced systemic inflammation in animals and humans. In this study we assessed the safety of eritoran administration in patients undergoing cardiac surgery and obtained preliminary efficacy data for the prophylaxis of endotoxin-mediated surgical complications.

METHODS

A double-blind, randomized, ascending-dose, placebo-controlled study was conducted at nine hospitals. Patients undergoing coronary artery bypass graft and/or cardiac valvular surgery with cardiopulmonary bypass were enrolled. Patients received a 4-h infusion of placebo (n = 78) vs 2 mg (n = 24), 12 mg (n = 26), or 28 mg (n = 24) of eritoran initiated approximately 1 h before cardiopulmonary bypass.

RESULTS

No significant safety concerns were identified with continuous safety monitoring, and enrollment continued to the highest prespecified dose (28 mg). No statistically significant differences were observed in most variables related to systemic inflammation or organ dysfunction/injury.

CONCLUSIONS

This Phase II safety study suggests that the administration of the novel lipid A antagonist, eritoran, is not associated with overt toxicity in cardiac surgical patients. Blocking lipid A with eritoran does not appear to confer any clear benefit to elective cardiac surgical patients.

Improved Postoperative Outcomes Associated with Preoperative Statin Therapy

Statin therapy is well established for prevention of cardiovascular disease. Statins may also reduce postoperative mortality and morbidity via a pleiotropic (non-lipid-lowering) effect. The authors conducted a meta-analysis to determine the influence of statin treatment on adverse postoperative outcomes in patients undergoing cardiac, vascular, or noncardiovascular surgery. Two independent authors abstracted data from 12 retrospective and 3 prospective trials (n = 223,010 patients). A meta-analysis was performed to evaluate the overall effect of preoperative statin therapy on postoperative outcomes. Preoperative statin therapy was associated with 38% and 59% reduction in the risk of mortality after cardiac (1.9% vs. 3.1%; P = 0.0001) and vascular (1.7% vs. 6.1%; P = 0.0001) surgery, respectively. When including noncardiac surgery, a 44% reduction in mortality (2.2% vs. 3.2%; P = 0.0001) was observed. Preoperative statin therapy may reduce postoperative mortality in patients undergoing surgical procedures. However, the statin associated effects on postoperative cardiovascular morbidity are too variable to draw any conclusion.

The role of statins in cancer therapy

Administration of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, to ambulatory patients is associated with a lower incidence of long-term adverse cardiovascular events, including death, myocardial infarction, stroke, atrial fibrillation, and renal dysfunction. However, increasing clinical evidence suggests that statins, independent of their effects on serum cholesterol levels, may also play a potential role in the prevention and treatment of cancer. Specifically, statins have been shown to exert several beneficial antineoplastic properties, including decreased tumor growth, angiogenesis, and metastasis. The feasibility and efficacy of statins for the prevention and treatment of cancer is reviewed.

Preoperative statin therapy is associated with reduced cardiac mortality after coronary artery bypass graft surgery

OBJECTIVE

Statin therapy in ambulatory populations is associated with a significant reduction in adverse cardiovascular events, including death and myocardial infarction. Much less is known about the beneficial effects of statins on acute perioperative cardiovascular events. The purpose of this study was to determine whether preoperative statin therapy is associated with a reduced risk of early cardiac death or nonfatal, in-hospital postoperative myocardial infarction after primary, elective coronary artery bypass graft surgery requiring cardiopulmonary bypass.

METHODS

The Multicenter Study of Perioperative Ischemia (McSPI) Epidemiology II Study was a prospective, longitudinal study of 5436 patients undergoing coronary artery bypass graft surgery between November 1996 and June 2000 at 70 centers in 17 countries. The present study consisted of a pre-specified subset of these subjects divided into patients receiving (n = 1352) and not receiving (n = 1314) preoperative statin therapy. To control for potential bias related to use of statin therapy, the study estimated propensity scores by logistic regression to determine the predicted probability of inclusion in the "statin" group. Multivariate, stepwise logistic regression was then performed, controlling for patient demographics, medical history, operative characteristics, and propensity score to determine whether preoperative statin therapy was independently associated with a reduction in the risk of early (DOS-POD3) cardiac death and/or nonfatal, in-hospital postoperative myocardial infarction.

RESULTS

Preoperative statin therapy was independently associated with a significant reduction (adjusted odds ratio [OR] 0.25; 95% confidence intervals [CI] 0.07-0.87) in the risk of early cardiac death after primary, elective coronary bypass surgery (0.3% vs 1.4%; P < .03), but was not associated with a reduced risk of postoperative nonfatal, in-hospital myocardial infarction (7.9% vs 6.2%; P = not significant). Discontinuation of statin therapy after surgery was independently associated with a significant increase in late (POD4-discharge) all-cause mortality (adjusted OR 2.64; 95% CI 1.32-5.26) compared with continuation of statin therapy (2.64% vs 0.60%; P < .01). This was true even when controlling for the postoperative discontinuation of aspirin, beta-blocker, or angiotensin-converting enzyme inhibitor therapy. Discontinuation of statin therapy after surgery was also independently associated with a significant increase in late cardiac mortality (adjusted OR 2.95; 95% CI 1.31-6.66) compared with continuation of statin therapy (1.91% vs 0.45%; P < 0.01).

CONCLUSIONS

Preoperative statin use is associated with reduced cardiac mortality after primary, elective coronary artery bypass grafting. Postoperative statin discontinuation is associated with increased in-hospital mortality. Although further randomized trials are needed to confirm these findings, these data suggest the importance of perioperative statin administration.

Obesity in Diabetic Patients Undergoing Coronary Artery Bypass Graft Surgery Is Associated with Increased Postoperative Morbidity

Background

Despite the fact that obesity is a known risk factor for cardiovascular disease, many studies have failed to demonstrate that obesity is independently associated with an increased risk of cardiovascular morbidity and mortality in nondiabetic patients undergoing coronary artery bypass graft surgery. The authors investigated the influence of obesity on adverse postoperative outcomes in diabetic and nondiabetic patients after primary coronary artery bypass surgery.

Methods

A retrospective cohort study of patients undergoing primary coronary artery bypass surgery (n = 9,862) between January 1995 and December 2004 at the Texas Heart Institute was performed. Diabetic (n = 3,374) and nondiabetic patients (n = 6,488) were classified into five groups, according to their body mass index: normal weight (n = 2,148), overweight (n = 4,257), mild obesity (n = 2,298), moderate obesity (n = 785), or morbid obesity (n = 338). Multivariate, stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications to determine whether obesity was independently associated with an increased risk of adverse postoperative outcomes.

Results

Obesity in nondiabetic patients was not independently associated with an increased risk of adverse postoperative outcomes. In contrast, obesity in diabetic patients was independently associated with a significantly increased risk of postoperative respiratory failure (odds ratio [OR], 2.26; 95% confidence interval [CI], 1.41-3.61; P &lt; 0.001), ventricular tachycardia (OR, 2.27; 95% CI, 1.18-4.35; P &lt; 0.02), atrial fibrillation (OR, 1.56; 95% CI, 1.03-2.38; P &lt; 0.04), atrial flutter (OR, 2.38; 95% CI, 1.29-4.40; P &lt; 0.01), renal insufficiency (OR, 1.66; 95% CI, 1.10-3.41; P &lt; 0.03), and leg wound infection (OR, 5.34; 95% CI, 2.27-12.54; P &lt; 0.001). Obesity in diabetic patients was not independently associated with an increased risk of mortality, stroke, myocardial infarction, sepsis, or sternal wound infection.

Conclusion

Obesity in diabetic patients is an independent predictor of worsened postoperative outcomes after primary coronary artery bypass graft surgery.

QTc interval prolongation predicts postoperative mortality in heart failure patients undergoing surgical revascularization

QTc interval prolongation is associated with increased mortality rates in patients with advanced heart failure. We investigated the predictive value of prolonged QTc interval in 567 patients with heart failure who were undergoing coronary artery bypass graft surgery The patients were in New York Heart Association class III or IV, with left ventricular ejection fractions of 0.40 or less. Before surgery, the QT interval duration was measured in leads II and V4 of the standard electrocardiogram and corrected by use of the Bazett formula. The QTc interval was prolonged (>440 msec) in 243 patients (43%) and normal in 324 (57%). The 2 study groups--prolonged QTc versus normal QTc--did not differ in terms of age (62 +/- 11 years vs 64 +/- 10 years, P=0.65), sex (80% male vs 76% male, P=0.31), ejection fraction (0.29 +/- 0.08 vs 0.29 +/- 0.09, P=0.72), hypertension (82% vs 78%, P=0.34), or diabetes (11% vs 7%, P=0.10). Within 1 month after coronary artery bypass grafting, 22 of 243 patients (9.1%) in the prolonged QTc group died, compared with 5 of 324 in the normal QTc group (1.5%) (P=0.0001). QTc interval prolongation was the only independent predictor of postoperative mortality on multivariate analysis (P=0.002). We conclude that patients with heart failure and preoperative QTc interval prolongation have increased mortality rates after coronary artery bypass grafting.

Pharmacogenetics of Anesthetic and Analgesic Agents

Predicting a patient's response to a particular drug has long been a goal of clinicians. Rapid advances in molecular biology have enabled researchers to identify associations between an individual's genetic profile and drug response. Pharmacogenetics is the study of the molecular mechanisms that underlie individual differences in drug metabolism, efficacy, and side effects. The pharmacogenetics of commonly used anesthetic and analgesic agents are reviewed.

Statins are associated with a reduced incidence of perioperative mortality after coronary artery bypass graft surgery

BACKGROUND

Statin therapy in nonsurgical patient populations is associated with a significant reduction in adverse cardiovascular events, including death, myocardial infarction (MI), and stroke. Recently, statin therapy was shown to be associated with a reduced incidence of postoperative mortality in patients undergoing major noncardiac vascular surgery. We investigated the influence of preoperative statin therapy on adverse outcomes after primary coronary artery bypass graft (CABG) surgery.

METHODS AND RESULTS

A retrospective cohort study of patients undergoing primary CABG surgery with cardiopulmonary bypass (CPB) (n=1663) between January 1, 2000 and December 31, 2001 at the Texas Heart Institute was performed. Patients were classified into 2 groups: patients receiving preoperative statin therapy (n=943) and patients not receiving preoperative antihyperlipidemic therapy (n=720). To determine if preoperative statin therapy was independently associated with a reduction in the risk of adverse postoperative outcomes, multivariate stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications. Multivariate logistic regression analysis demonstrated that preoperative statin therapy was independently associated with a significant reduction ( approximately 50%) in the risk of 30-day all-cause mortality (3.75% versus 1.80%; P<0.05). The adjusted odds ratio for early mortality in patients receiving preoperative statin therapy compared with patients not receiving antihyperlipidemic agents was 0.53 (95% CI, 0.28 to 0.99). Statin therapy was not independently associated with a reduced risk of postoperative MI, cardiac arrhythmias, stroke, or renal dysfunction. In an attempt to further control for selection bias related to the choice of therapy, multivariate analysis of a propensity-matched cohort of 1362 patients revealed that preoperative statin therapy was independently associated with a significant reduction in the composite endpoint of 30-day all-cause mortality and stroke (7.1% versus 4.6%; P<0.05).

CONCLUSIONS

Preoperative statin therapy may reduce the risk of early mortality after primary CABG surgery with CPB.

Clopidogrel and bleeding in patients undergoing elective coronary artery bypass grafting

OBJECTIVE

In an effort to minimize transfusions in patients undergoing elective coronary artery bypass grafting operations after recent clopidogrel exposure, we studied laboratory tests predictive of platelet dysfunction and used a strict algorithm-driven treatment of bleeding.

METHODS

Forty-five patients receiving clopidogrel within 6 days of the operation and 45 control subjects were studied. Prothrombin time, activated partial thromboplastin time, platelet count, and platelet function test results were measured before heparinization, after protamine administration, and then every 2 hours. No transfusions were administered unless a patient met both laboratory and clinical criteria.

RESULTS

Algorithm-driven treatment of bleeding significantly reduced the mean units of all blood components transfused by about one third, as shown by comparison with current control and historical data. Compared with current control subjects, clopidogrel recipients required significantly more transfusions of platelets (9.0 +/- 1.7 vs 1.2 +/- 0.5 U; P <.0001) and packed red blood cells (4.3 +/- 0.6 vs 2.3 +/- 0.5 U; P =.01) and required longer periods of controlled ventilation (12.4 +/- 1.3 vs 8.6 +/- 0.8 hours; P =.02). Preoperative platelet dysfunction before heparin administration for cardiopulmonary bypass, as measured by using adenosine diphosphate aggregometry (response <40%), predicted all but 1 case of severe coagulopathy requiring multiple transfusions (16.6 +/- 2.8 U of platelets and 5.8 +/- 1.0 U of packed red blood cells).

CONCLUSIONS

A strict transfusion algorithm can reduce the transfusion requirement for all blood components. Preheparin testing of platelet function with adenosine diphosphate aggregometry can identify patients at highest risk for perioperative bleeding and transfusions and might further reduce the perioperative transfusion requirement.

Budget Negotiation for Industry-Sponsored Clinical Trials

The specialty of anesthesia is well suited to attract industry-sponsored clinical trials and research revenues because of its fundamental contributions to surgery, critical care, and pain medicine. However, the performance and budgeting of industry-sponsored clinical research over the past decade has been significantly altered by the rapid growth of commercially oriented networks of contract-research organizations and site-management organizations. Further, the competitive nature of today's clinical research climate can make the planning and negotiating of study budgets and contracts stressful, time consuming, frustrating, and full of pitfalls. Because a clinical trial contract is a fixed-price agreement, investigators are obligated to perform the work described in the contract, even if the actual costs exceed the study contract. Successful budgeting for the performance of an industry-sponsored clinical trial thus requires a thorough understanding of the direct and indirect costs associated with performing clinical research. We reviewed budget and contractual considerations for the successful negotiation and performance of industry-sponsored clinical research.

[Gene polymorphism in intensive care patients. Is the course of disease predetermined?]

Die enormen Fortschritte der molekularbiologischen Grundlagenforschung haben unser Verständnis der pathophysiologischen Mechanismen von Erkrankungen entscheidend vorangetrieben. Die große interindividuelle Variabilität von Krankheitsverläufen in der Intensivmedizin lässt sich häufig nicht allein durch bekannte Risikofaktoren erklären. Vielmehr scheint auch der Genotyp des einzelnen Patienten Inzidenz, Verlauf und Mortalität schwerster Krankheitsbilder zu verändern. Im Rahmen von Genassoziationsstudien wurde eine Vielzahl genetischer Polymorphismen untersucht, die in der Intensivmedizin eine Rolle spielen könnten. Beeinflusst werden neben Entzündungsreaktionen [z. B. Tumor-Nekrose-Faktor- (TNF-)α, Interleukin- (Il-)10] auch spezifische Infektionserkrankungen (Pneumonie, Meningitis), Sepsis oder „acute respiratory distress syndrome“ (ARDS) ebenso wie die Letalität schwerst traumatisierter Patienten [Polytrauma, Schädel-Hirn-Trauma (SHT)]. Die weitere Identifizierung solcher Allo- und Haplotypen kann nicht nur erklären, warum intensivmedizinische Patienten unterschiedlich auf vergleichbare Therapien ansprechen, sondern möglicherweise auch mittels verbesserter Risikostratifizierung und an den Genotyp des einzelnen Patienten angepasster Therapie zu einer Verringerung von Morbidität und Mortalität beitragen.

Vascular ischaemia and reperfusion injury

Although restoration of blood flow to an ischaemic organ is essential to prevent irreversible tissue injury, reperfusion per se may result in a local and systemic inflammatory response that may augment tissue injury in excess of that produced by ischaemia alone. Cellular damage after reperfusion of previously viable ischaemic tissues is defined as ischaemia-reperfusion (I-R) injury. I-R injury is characterized by oxidant production, complement activation, leucocyte-endothelial cell adhesion, platelet-leucocyte aggregation, increased microvascular permeability and decreased endothelium-dependent relaxation. In its severest form, I-R injury can lead to multiorgan dysfunction or death. Although our understanding of the pathophysiology of I-R injury has advanced significantly in the last decade, such experimentally derived concepts have yet to be fully integrated into clinical practice. Treatment of I-R injury is also confounded by the fact that inhibition of I-R-associated inflammation might disrupt protective physiological responses or result in immunosuppression. Thus, while timely reperfusion of the ischaemic area at risk remains the cornerstone of clinical practice, therapeutic strategies such as ischaemic preconditioning, controlled reperfusion, and anti-oxidant, complement or neutrophil therapy may significantly prevent or limit I-R-induced injury in humans.