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

Predictors of Acute Kidney Injury Following Surgical Valve Replacement

BACKGROUND

 Acute kidney injury is a serious complication after surgical valve replacement and holds increased mortality rates.

OBJECTIVES

 To study predictors of acute kidney injury after surgical valve replacement.

MATERIALS AND METHODS

 Patients who underwent valve surgery procedures at our center were included. Procedures included aortic valve replacement (AVR), mitral valve replacement (MVR), AVR with coronary artery bypass grafting (CABG), MVR with CABG, or AVR and MVR with/without CABG.

RESULTS

 A total of 346 patients were included. The mean age was 51.56 (16.1). Males (n = 178) comprised 51%.At the univariate level analysis, predictors of acute kidney injury were found including age, ejection fraction, hypertension, history of CAD, emergency surgery, recent myocardial infarction, diabetes, atrial fibrillation, history of heart failure, mitral regurgitation (MR), pump time >120 minutes, aortic cross clamp >90 minutes, perioperative blood transfusion, re-exploration for bleeding, use of mechanical and biologic valve in aortic position, use of biologic valve in mitral position, prolonged inotropic support, postoperative stroke, and use of angiotensin converting enzyme inhibitors (ACEi) < a month, (all p < 0.05).By Logistic regression analysis, Age (p < 0.0001, odds ratio[AOR] = 1.076), hypertension (p = 0.039, AOR = 1.829), heart failure (p = 0.019, AOR = 2.448), MR (p = 0.0001, AOR = 3.110), use of ACEi <month (p = 0.043, AOR= 2.181), pump time >120 minutes (p = 0.022, AOR = 1.797), perioperative blood transfusion (p = 0.008, AOR = 2.532), and prolonged inotropic support (p = 0.012, AOR = 2.591) were significant and independent predictors of AKI.

CONCLUSION

 Independent predictors of acute kidney injury following valve surgeries include age, hypertension, heart failure, MR, use of ACEi <month, perioperative blood transfusion, and prolonged pump time or inotropic support.

Perioperative angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blockers for preventing mortality and morbidity in adults

BACKGROUND

Perioperative hypertension requires careful management. Angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs) have shown efficacy in treating hypertension associated with surgery. However, there is lack of consensus about whether they can prevent mortality and morbidity.

OBJECTIVES

To systematically assess the benefits and harms of administration of ACEIs or ARBs perioperatively for the prevention of mortality and morbidity in adults (aged 18 years and above) undergoing any type of surgery under general anaesthesia.

SEARCH METHODS

We searched the current issue of the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 12), Ovid MEDLINE (1966 to 8 December 2014), EMBASE (1980 to 8 December 2014), and references of the retrieved randomized trials, meta-analyses, and systematic reviews.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing perioperative administration of ACEIs or ARBs with placebo in adults (aged 18 years and above) undergoing any type of surgery under general anaesthesia. We excluded studies in which participants underwent procedures that required local anaesthesia only, or participants who had already been on ACEIs or ARBs.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, assessed the risk of bias, and extracted data. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included seven RCTs with a total of 571 participants in the review. Two of the seven trials involved 36 participants undergoing non-cardiac vascular surgery (infrarenal aortic surgery), and five involved 535 participants undergoing cardiac surgery, including valvular surgery, coronary artery bypass surgery, and cardiopulmonary bypass surgery. The intervention was started from 11 days to 25 minutes before surgery in six trials and during surgery in one trial. We considered all seven RCTs to carry a high risk of bias. The effects of ACEIs or ARBs on perioperative mortality and acute myocardial infarction were uncertain because the quality of the evidence was very low. The risk of death was 2.7% in the ACEIs or ARBs group and 1.6% in the placebo group (risk ratio (RR) 1.61; 95% confidence interval (CI) 0.44 to 5.85). The risk of acute myocardial infarction was 1.7% in the ACEIs or ARBs group and 3.0% in the placebo group (RR 0.55; 95% CI 0.14 to 2.26). ACEIs or ARBs may improve congestive heart failure (cardiac index) perioperatively (mean difference (MD) -0.60; 95% CI -0.70 to -0.50, very low-quality evidence). In terms of rate of complications, there was no difference in perioperative cerebrovascular complications (RR 0.48; 95% CI 0.18 to 1.28, very low-quality evidence) and hypotension (RR 1.95; 95% CI 0.86 to 4.41, very low-quality evidence). Cardiac surgery-related renal failure was not reported. ACEIs or ARBs were associated with shortened length of hospital stay (MD -0.54; 95% CI -0.93 to -0.16, P value = 0.005, very low-quality evidence). These findings should be interpreted cautiously due to likely confounding by the clinical backgrounds of the participants. ACEIs or ARBs may shorten the length of hospital stay, (MD -0.54; 95% CI -0.93 to -0.16, very low-quality evidence) Two studies reported adverse events, and there was no evidence of a difference between the ACEIs or ARBs and control groups.

AUTHORS' CONCLUSIONS

Overall, this review did not find evidence to support that perioperative ACEIs or ARBs can prevent mortality, morbidity, and complications (hypotension, perioperative cerebrovascular complications, and cardiac surgery-related renal failure). We found no evidence showing that the use of these drugs may reduce the rate of acute myocardial infarction. However, ACEIs or ARBs may increase cardiac output perioperatively. Due to the low and very low methodology quality, high risk of bias, and lack of power of the included studies, the true effect may be substantially different from the observed estimates. Perioperative (mainly elective cardiac surgery, according to included studies) initiation of ACEIs or ARBs therapy should be individualized.

Acute kidney injury following surgical aortic valve replacement

BACKGROUND

Acute kidney injury (AKI) is a significant complication of surgical aortic valve replacement (SAVR). This study sought to describe AKI following SAVR, its risk factors, predictors and effect on long-term survival.

METHODS

We retrospectively reviewed 2169 patients who underwent isolated SAVR between 2000 and 2012. The main end-points were occurrence of AKI, postoperative complications, and short- and long-term survival rates following SAVR. Patients were divided into two groups: AKI+ (n = 181) and AKI- (n = 1945).

RESULTS

AKI occurred in 8.5% of patients, of which 3.9% (n = 7) needed dialysis. Predictors of AKI after SAVR were body mass index (BMI) and intraoperative packed red blood cells (PRBC) transfusion. AKI+ patients had a more complicated postoperative course and higher cumulative mortality (25% vs. 17%, p = 0.012) with a median follow-up of 4.1 years. AKI was not found to be an independent predictor of mortality.

CONCLUSIONS

Predictors of AKI after SAVR are increased BMI and intraoperative PRBC transfusion. AKI conferred an increase in hospital length of stay and cumulative mortality while the need for postoperative dialysis was associated with the most complicated hospital stays and the highest in-hospital and cumulative mortalities; therefore careful recognition of patients at risk of AKI is warranted for a better preoperative renal optimization. However, incidence of AKI was lower than what is reported after both on-CPB cardiac surgeries and transcatheter aortic valve replacement, moreover AKI was not found to be an independent predictor of mortality.

Acute kidney injury after aortic valve replacement: incidence, risk factors and outcomes

The occurrence of acute kidney injury (AKI) following aortic valve replacement (AVR) has very serious clinical implications and has therefore been the focus of several studies. The authors report the results of previous studies evaluating both transcatheter AVR (TAVR) and indirectly surgical AVR (SAVR) through looking at cardiopulmonary bypass (CPB) cardiac surgeries, and identify the incidence, predictors and outcomes of AKI following AVR. In most studies, AKI was defined using the Risk, Injury, Failure, Loss and End Stage, Valve Academic Research Consortium (modified Risk, Injury, Failure, Loss and End Stage) or Valve Academic Research Consortium-2 (Acute Kidney Injury Network) AKI classification criteria. Twelve studies including more than 90,000 patients undergoing cardiac surgery on CPB were considered as well as 26 studies with more than 6000 patients undergoing TAVR. Depending on the definition used, AKI occurred in 3.4-43% of SAVR cases with up to 2.5% requiring dialysis, and in 3.4-57% of TAVR cases. Factors identified as independent predictors of AKI were: baseline kidney failure, EUROSCORE, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, anemia, peripheral vascular disease, heart failure, surgical priority, CPB time, reoperation, use of intra-aortic balloon pump, need for re-exploration, contrast agent volume, transapical access, blood transfusion, postoperative thrombocytopenia, postoperative leukocytosis as well as demographic variables such as age and female gender. The 30-day mortality rate for patients with AKI following SAVR ranged from 5.5 to 46% and was 3- to 16-times higher than in those without AKI. Similarly, patients who developed AKI after TAVR had a mortality rate of 7.8-29%, which was two- to eight-times higher than those who did not suffer from AKI. AKI confers up to a fourfold increase in 1-year mortality. Finally, hospital length of stay was significantly increased in patients with AKI in both SAVR and TAVR groups, with increases up to 3- and 2.5-times, respectively.

Cardiac surgery-associated acute kidney injury

Cardiac surgery-associated acute kidney injury (AKI) is a major health problem that is extremely common and has a significant effect on cardiac surgical outcomes. AKI occurs in nearly 30 % of patients undergoing cardiac surgery, with about 1-2 % of these ultimately requiring dialysis. The development of AKI predicts a significant increase in morbidity and mortality independent of other risk factors. The pathogenetic mechanisms associated with cardiac surgery-associated AKI include several biochemical pathways, of which the most important are hemodynamic, inflammatory and nephrotoxic factors. Risk factors for AKI have been identified in several models, and these facilitate physicians to prognosticate and develop a strategy for tackling patients predisposed to developing renal dysfunction. Effective therapy of the condition is still suboptimal, and hence the accent has always been on risk factor modification. Thus, strategies for reducing preoperative anemia, perioperative blood transfusions and surgical re-explorations may be effective in attenuating the incidence and severity of this complication.

Angiotensin-converting enzyme inhibition or mineralocorticoid receptor blockade do not affect prevalence of atrial fibrillation in patients undergoing cardiac surgery

OBJECTIVE

This study tested the hypothesis that interruption of the renin-angiotensin system with either an angiotensin-converting enzyme inhibitor or a mineralocorticoid receptor antagonist will decrease the prevalence of atrial fibrillation after cardiac surgery.

DESIGN

Randomized double-blind placebo-controlled study.

SETTING

University-affiliated hospitals.

PATIENTS

Four hundred forty-five adult patients in normal sinus rhythm undergoing elective cardiac surgery.

INTERVENTIONS

One week to 4 days prior to surgery, patients were randomized to treatment with placebo, ramipril (2.5 mg the first 3 days followed by 5 mg/day, with the dose reduced to 2.5 mg/day on the first postoperative day only), or spironolactone (25 mg/day).

MEASUREMENTS

The primary endpoint was the occurrence of electrocardiographically confirmed postoperative atrial fibrillation. Secondary endpoints included acute renal failure, hyperkalemia, the prevalence of hypotension, length of hospital stay, stroke, and death.

MAIN RESULTS

The prevalence of atrial fibrillation was 27.2% in the placebo group, 27.8% in the ramipril group, and 25.9% in the spironolactone group (p=.95). Patients in the ramipril (0.7%) or spironolactone (0.7%) group were less likely to develop acute renal failure than those randomized to placebo (5.4%, p=.006). Patients in the placebo group tended to be hospitalized longer than those in the ramipril or spironolactone group (6.8±8.2 days vs. 5.7±3.2 days and 5.8±3.4 days, respectively, p=.08 for the comparison of placebo vs. the active treatment groups using log-rank test). Compared with patients in the placebo group, patients in the spironolactone group were extubated sooner after surgery (576.4±761.5 mins vs. 1091.3±3067.3 mins, p=.04).

CONCLUSIONS

Neither angiotensin-converting enzyme inhibition nor mineralocorticoid receptor blockade decreased the primary outcome of postoperative atrial fibrillation. Treatment with an angiotensin-converting enzyme inhibitor or mineralocorticoid receptor antagonist was associated with decreased acute renal failure. Spironolactone use was also associated with a shorter duration of mechanical ventilation after surgery.

Comparative effects of angiotensin receptor blockade and ACE inhibition on the fibrinolytic and inflammatory responses to cardiopulmonary bypass

The effects of angiotensin-converting enzyme (ACE) inhibition and angiotensin II type 1 receptor blockade (ARB) on fibrinolysis and inflammation following cardiopulmonary bypass (CPB) are uncertain. This study tested the hypothesis that ACE inhibition enhances fibrinolysis and inflammation to greater extent than ARB in patients undergoing CPB.One week to five days prior to surgery, patients were randomized to ramipril 5mg/day,candesartan 16mg/day or placebo.ACE inhibition increased intraoperative bradykinin and tissue-type plasminogen activator (t-PA) concentrations compared to ARB. Both ACE inhibition and ARB decreased plasma transfusion compared to placebo, but only ACE inhibition decreased length of stay. Neither ACE inhibition nor ARB significantly affectedplasminogen activator inhibitor-1 (PAI-1), interleukin (IL)-6, IL-8, or IL-10 concentrations. ACE inhibition enhanced intraoperative fibrinolysis without increasing red cell transfusion risk. In contrast, neither ACE inhibition nor ARB affected the inflammatory response. ACE inhibitors and ARB may be safely continued until the day of surgery.

Angiotensin-converting enzyme inhibition alters the inflammatory and fibrinolytic response to cardiopulmonary bypass in children

OBJECTIVE

Many children with a congenital heart defect undergo surgical correction requiring cardiopulmonary bypass. One-sixth of these patients take an angiotensin-converting enzyme inhibitor for heart failure treatment. The effect of angiotensin-converting enzyme inhibition on the fibrinolytic and inflammatory response in children undergoing cardiopulmonary bypass is unknown. In adults, angiotensin-converting enzyme inhibition attenuates the increase in plasminogen activator inhibitor-1 after cardiopulmonary bypass, whereas the effect on the interleukin-6 response is uncertain. This study tests the hypothesis that preoperative angiotensin-converting enzyme inhibition attenuates postoperative plasminogen activator inhibitor-1 and interleukin-6 expression after cardiopulmonary bypass in children.

DESIGN

Single-center prospective, randomized, nonblinded study.

SETTING

University-affiliated pediatric hospital.

PATIENTS

Children undergoing elective surgical correction of a congenital heart defect requiring cardiopulmonary bypass and taking an angiotensin-converting enzyme inhibitor.

INTERVENTIONS

Children were randomized to continue angiotensin-converting enzyme inhibitor until the morning of surgery (angiotensin-converting enzyme inhibitor group, n = 11) or to discontinue therapy 72 hrs before surgery (no angiotensin-converting enzyme inhibitor group, n = 9).

MEASUREMENT AND MAIN RESULTS

Blood samples were collected at baseline before cardiopulmonary bypass, at 30 mins of cardiopulmonary bypass, on arrival to the intensive care unit, and on postoperative day 1. Baseline bradykinin concentrations were significantly higher and angiotensin-converting enzyme activity significantly lower in the angiotensin-converting enzyme inhibitor group compared with the no angiotensin-converting enzyme inhibitor group (p = .04 and .001, respectively). Plasminogen activator inhibitor-1 antigen increased 15-fold after cardiopulmonary bypass and peaked on postoperative day 1 (from 4.6 ± 1.2 to 67.7 ± 9.5 ng/mL; p < .001). Postoperative day 1 plasminogen activator inhibitor-1 antigen correlated significantly with cardiopulmonary bypass time (r2 = 0.40, p = .03) and was significantly lower in the angiotensin-converting enzyme inhibitor group compared with the no angiotensin-converting enzyme inhibitor group (p = .03). The proinflammatory markers interleukin-6 and interleukin-8 as well as the anti-inflammatory marker interleukin-10 increased significantly after cardiopulmonary bypass (all p < .001). Interleukin-6 concentrations were significantly higher in the angiotensin-converting enzyme inhibitor group after cardiopulmonary bypass (p = .02) even after controlling for potential confounding factors such as age, cardiopulmonary bypass time, and transfusion volume.

CONCLUSION

Angiotensin-converting enzyme inhibition attenuates the increase in postoperative plasminogen activator inhibitor-1 but enhances the interleukin-6 response in children undergoing cardiopulmonary bypass.

Quinaprilat: a review of its pharmacokinetics, pharmacodynamics, toxicological data and clinical application

BACKGROUND

Quinaprilat is an ACE inhibitor for intravenous use especially in patients with arterial hypertension or chronic heart failure. In contrast to the oral prodrug quinapril, it has not been approved for clinical application.

OBJECTIVE

In this review, the pharmacokinetic and pharmacodynamic profile of quinaprilat as well as toxicological data and results of preclinical and clinical studies are summarized.

METHODS

In a PubMed search for the terms "quinaprilat" and "quinapril", literature relevant for this review was selected.

RESULTS

Quinaprilat is a potent nonsulfhydryl selective ACE inhibitor with a short elimination half-life of 2 - 3 h, but due to slow dissociation from tissue ACE, once daily dosing is sufficient for effective ACE inhibition. Quinaprilat is excreted mainly in urine. In long-term animal studies, quinaprilat was not teratogenic, mutagenic or carcinogenic. However, due to the risk of fetal and neonatal morbidity and death, it should not be administrated in pregnancy. Quinaprilat is characterized by an excellent safety profile; adverse events occur infrequently and are rarely serious.

CONCLUSION

Quinaprilat is an attractive ACE inhibitor, which potently inhibits tissue ACE.

Haemodynamic effects of intravenous quinaprilat in comparison to sodium nitroprusside in patients with chronic heart failure

We compared the haemodynamic effects of intravenous boluses of the ACE inhibitor quinaprilat with an intravenous infusion of sodium nitroprusside in 23 patients with chronic heart failure (NYHA Class III or IV). At the highest drug doses, sodium nitroprusside significantly increased stroke volume index (+6.63 ml/m(2), p=0.045), whereas quinaprilat induced only a minor increase (+1.79 ml/m(2), n.s.).

Acute kidney injury associated with cardiac surgery

Acute renal failure (ARF) occurs in up to 30% of patients who undergo cardiac surgery, with dialysis being required in approximately 1% of all patients. The development of ARF is associated with substantial morbidity and mortality independent of all other factors. The pathogenesis of ARF involves multiple pathways. Hemodynamic, inflammatory, and nephrotoxic factors are involved and overlap each other in leading to kidney injury. Clinical studies have identified risk factors for ARF that can be used to determine effectively the risk for ARF in patients who undergo bypass surgery. These high-risk patients then can be targeted for renal protective strategies. Thus far, no single strategy has demonstrated conclusively its ability to prevent renal injury after bypass surgery. Several compounds such as atrial natriuretic peptide and N-acetylcysteine have shown promise, but large-scale trials are needed.

[Continuous infusion of remifentanil and target-controlled infusion of propofol for coronary surgery in elderly patients: comparison with continuous infusion of remifentanil and propofol]

OBJECTIVES

Comparison of the length of mechanical ventilation and postoperative complications after coronary surgery in elderly patients anaesthetised with propofol associated with either alfentanil or remifentanil.

STUDY DESIGN

Retrospective study with an historic control group.

PATIENTS

Three hundred thirty-eight consecutive patients (75-year-old or more) undergoing isolated coronary surgery. One hundred and fifty seven patients operated between January 1998 and June 2000 received alfentanil (1 microg/kg/minute) with a manually control infusion of propofol, 181 operated between July 2000 and 2002, remifentanil 0.25 microg/kg/minute with target controlled infusion of propofol (target blood concentration: 1.5 to 2 microg/ml).

METHODS

The two groups were compared for preoperative and surgical data. The length of mechanical ventilation, stay in ICU and the main postoperative complications were compared between the two groups.

RESULTS

Length of mechanical ventilation was significantly reduced in the remifentanil group (6 +/- 9 h vs. 13 +/- 63 h ; p <0.0001), 70% of the patients were extubated before the 6th postoperative hours against 53% in the alfentanil group (p =0.0023). This was not associated with a reduction of stay in ICU or postoperative complications. During surgery, an increased used of vasopressor was observed in the remifentanil group (40.2% vs 2.4% ; p <0.0001) with a postoperative elevation of blood concentration of CKMb (35.7 +/- 38.2 microg/l, vs. 27.7 +/- 31.9 microg/l, p =0.02).

CONCLUSION

Elderly patients undergoing coronary surgery were extubated earlier with remifentanil. However, this had no effect on duration of ICU stay but was associated with an increased used of vasopressor.