Preoperative administration of steroids: influence on adhesion molecules and cytokines after cardiopulmonary bypass

Methylprednisolone alleviates lung injury in sepsis by regulating miR-151-5p/USP38 pathway

BACKGROUND

Acute lung injury (ALI) is manifested by increased blood vessel permeability within the lungs and subsequent impairment of alveolar gas exchange. Methylprednisolone (MP) is commonly used as a treatment for ALI to reduce inflammation, yet its molecular mechanism remains unclear. This study aims to explore the underlying mechanisms of MP on ALI in a model induced by lipopolysaccharide (LPS).

MATERIAL AND METHODS

The proliferation, viability, apoptosis, and miR-151-5p expression of alveolar type II epithelial cells (AECII) were detected using the cell EdU assay, Annexin V/PI Apoptosis Kit, counting kit-8 (CCK-8) assay, and RT-qPCR. Western blot analysis was used to detect the Usp38 protein level. IL-6 and TNF-α were measured by ELISA. The combination of miR-151-5p and USP38 was determined by chromatin immunoprecipitation (ChIP)-PCR and dual-luciferase reporter assay.

RESULTS

MP greatly improved pulmonary function in vivo, reduced inflammation, and promoted the proliferation of the alveolar type II epithelial cells (AECII) in vitro. By comparing the alterations of microRNAs in lung tissues between MP treatment and control groups, we found that miR-151-5p exhibited a significant increase after LPS-treated AECII, but decreased after MP treatment. Confirmed by a luciferase reporter assay, USP38, identified as a downstream target of miR-151-5p, was found to increase after MP administration. Inhibition of miR-151-5p or overexpression of USP38 in AECII significantly improved the anti-inflammatory, anti-apoptotic, and proliferation-promotive effects of MP.

CONCLUSION

In summary, our data demonstrated that MP alleviates the inflammation and apoptosis of AECII induced by LPS, and promotes the proliferation of AECII partially via miR-151-5p suppression and subsequent USP38 activation.

Prophylactic corticosteroids for cardiopulmonary bypass in adult cardiac surgery

BACKGROUND

Cardiac surgery triggers a strong inflammatory reaction, which carries significant clinical consequences. Corticosteroids have been suggested as a potential perioperative strategy to reduce inflammation and help prevent postoperative complications. However, the safety and effectiveness of perioperative corticosteroid use in adult cardiac surgery is uncertain. This is an update of the 2011 review with 18 studies added.

OBJECTIVES

Primary objective: to estimate the effects of prophylactic corticosteroid use in adults undergoing cardiac surgery with cardiopulmonary bypass on the: - co-primary endpoints of mortality, myocardial complications, and pulmonary complications; and - secondary outcomes including atrial fibrillation, infection, organ injury, known complications of steroid therapy, prolonged mechanical ventilation, prolonged postoperative stay, and cost-effectiveness.

SECONDARY OBJECTIVE

to explore the role of characteristics of the study cohort and specific features of the intervention in determining the treatment effects via a series of prespecified subgroup analyses.

SEARCH METHODS

We used standard, extensive Cochrane search methods to identify randomised studies assessing the effect of corticosteroids in adult cardiac surgery. The latest searches were performed on 14 October 2022.

SELECTION CRITERIA

We included randomised controlled trials in adults (over 18 years, either with a diagnosis of coronary artery disease or cardiac valve disease, or who were candidates for cardiac surgery with the use of cardiopulmonary bypass), comparing corticosteroids with no treatments. There were no restrictions with respect to length of the follow-up period. All selected studies qualified for pooling of results for one or more endpoints.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were all-cause mortality, and cardiac and pulmonary complications. Secondary outcomes were infectious complications, gastrointestinal bleeding, occurrence of new post-surgery atrial fibrillation, re-thoracotomy for bleeding, neurological complications, renal failure, inotropic support, postoperative bleeding, mechanical ventilation time, length of stays in the intensive care unit (ICU) and hospital, patient quality of life, and cost-effectiveness. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

This updated review includes 72 randomised trials with 17,282 participants (all 72 trials with 16,962 participants were included in data synthesis). Four trials (6%) were considered at low risk of bias in all the domains. The median age of participants included in the studies was 62.9 years. Study populations consisted mainly (89%) of low-risk, first-time coronary artery bypass grafting (CABG) or valve surgery. The use of perioperative corticosteroids may result in little to no difference in all-cause mortality (risk with corticosteroids: 25 to 36 per 1000 versus 33 per 1000 with placebo or no treatment; risk ratio (RR) 0.90, 95% confidence interval (CI) 0.75 to 1.07; 25 studies, 14,940 participants; low-certainty evidence). Corticosteroids may increase the risk of myocardial complications (68 to 86 per 1000) compared with placebo or no treatment (66 per 1000; RR 1.16, 95% CI 1.04 to 1.31; 25 studies, 14,766 participants; low-certainty evidence), and may reduce the risk of pulmonary complications (risk with corticosteroids: 61 to 77 per 1000 versus 78 per 1000 with placebo/no treatment; RR 0.88, 0.78 to 0.99; 18 studies, 13,549 participants; low-certainty evidence). Analyses of secondary endpoints showed that corticosteroids may reduce the incidence of infectious complications (risk with corticosteroids: 94 to 113 per 1000 versus 123 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.76 to 0.92; 28 studies, 14,771 participants; low-certainty evidence). Corticosteroids may result in little to no difference in incidence of gastrointestinal bleeding (risk with corticosteroids: 9 to 17 per 1000 versus 10 per 1000 with placebo/no treatment; RR 1.21, 95% CI 0.87 to 1.67; 6 studies, 12,533 participants; low-certainty evidence) and renal failure (risk with corticosteroids: 23 to 35 per 1000 versus 34 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.69 to 1.02; 13 studies, 12,799; low-certainty evidence). Corticosteroids may reduce the length of hospital stay, but the evidence is very uncertain (-0.5 days, 0.97 to 0.04 fewer days of length of hospital stay compared with placebo/no treatment; 25 studies, 1841 participants; very low-certainty evidence). The results from the two largest trials included in the review possibly skew the overall findings from the meta-analysis.

AUTHORS' CONCLUSIONS

A systematic review of trials evaluating the organ protective effects of corticosteroids in cardiac surgery demonstrated little or no treatment effect on mortality, gastrointestinal bleeding, and renal failure. There were opposing treatment effects on cardiac and pulmonary complications, with evidence that corticosteroids may increase cardiac complications but reduce pulmonary complications; however, the level of certainty for these estimates was low. There were minor benefits from corticosteroid therapy for infectious complications, but the evidence on hospital length of stay was very uncertain. The inconsistent treatment effects across different outcomes and the limited data on high-risk groups reduced the applicability of the findings. Further research should explore the role of these drugs in specific, vulnerable cohorts.

Effects of interventions targeting the systemic inflammatory response to cardiac surgery on clinical outcomes in adults

BACKGROUND

Organ injury is a common and severe complication of cardiac surgery that contributes to the majority of deaths. There are no effective treatment or prevention strategies. It has been suggested that innate immune system activation may have a causal role in organ injury. A wide range of organ protection interventions targeting the innate immune response have been evaluated in randomised controlled trials (RCTs) in adult cardiac surgery patients, with inconsistent results in terms of effectiveness.

OBJECTIVES

The aim of the review was to summarise the results of RCTs of organ protection interventions targeting the innate immune response in adult cardiac surgery. The review considered whether the interventions had a treatment effect on inflammation, important clinical outcomes, or both.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, conference proceedings and two trial registers were searched on October 2022 together with reference checking to identify additional studies.

SELECTION CRITERIA

RCTs comparing organ protection interventions targeting the innate immune response versus placebo or no treatment in adult patients undergoing cardiac surgery where the treatment effect on innate immune activation and on clinical outcomes of interest were reported.

DATA COLLECTION AND ANALYSIS

Searches, study selection, quality assessment, and data extractions were performed independently by pairs of authors. The primary inflammation outcomes were peak IL-6 and IL-8 concentrations in blood post-surgery. The primary clinical outcome was in-hospital or 30-day mortality. Treatment effects were expressed as risk ratios (RR) and standardised mean difference (SMD) with 95% confidence intervals (CI). Meta-analyses were performed using random effects models, and heterogeneity was assessed using I2.

MAIN RESULTS

A total of 40,255 participants from 328 RCTs were included in the synthesis. The effects of treatments on IL-6 (SMD -0.77, 95% CI -0.97 to -0.58, I2 = 92%) and IL-8 (SMD -0.92, 95% CI -1.20 to -0.65, I2 = 91%) were unclear due to heterogeneity. Heterogeneity for inflammation outcomes persisted across multiple sensitivity and moderator analyses. The pooled treatment effect for in-hospital or 30-day mortality was RR 0.78, 95% CI 0.68 to 0.91, I2 = 0%, suggesting a significant clinical benefit. There was little or no treatment effect on mortality when analyses were restricted to studies at low risk of bias. Post hoc analyses failed to demonstrate consistent treatment effects on inflammation and clinical outcomes. Levels of certainty for pooled treatment effects on the primary outcomes were very low.

AUTHORS' CONCLUSIONS

A systematic review of RCTs of organ protection interventions targeting innate immune system activation did not resolve uncertainty as to the effectiveness of these treatments, or the role of innate immunity in organ injury following cardiac surgery.

Effects of different doses of glucocorticoids on postoperative atrial fibrillation: a meta-analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery, and its occurrence is closely related to inflammation. This paper intends to apply meta-analysis to investigate the effect of glucocorticoids on POAF.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched using the internationally recognized systematic evaluation and retrieval strategy. Two review authors independently selected relevant studies and extracted data based on the Cochrane handbook for systematic reviews of interventions approach. Stata 17 was used for data analysis. In the subgroup analysis, we grouped the participant data according to differences in glucocorticoids dose and type of surgery. At the same time, we also conducted a meta-analysis on the possible infection and gastrointestinal injury caused by glucocorticoids use.

RESULTS

27 studies and 14,442 patients were finally included. Results from the random-effects model indicated that the incidence of POAF was lower in glucocorticoid group (RR 0.80, 95% CI 0.71-0.92, P = 0.001). According to the subgroup analysis result, low doses of glucocorticoids reduced the incidence of POAF (RR 0.81, 95% CI 0.71-0.92, P = 0.001). The effect of high doses glucocorticoids on the POAF was not statistically significant (RR 0.81, 95% CI 0.56-1.19, P = 0.286). In the coronary artery bypass grafting (CABG) subgroup, the glucocorticoids reduced the incidence of POAF (RR 0.71, 95% CI 0.58-0.87, P = 0.001). In the CABG OR Valvular Surgery group, the effect of glucocorticoids on POAF was not statistically significant (RR 0.88, 95% CI 0.75-1.03, P = 0.108). 15 studies documented postoperative complications of infection, two studies were excluded from the system because the end point event was 0, and meta-analysis showed no increased risk of infection from glucocorticoid use (RR 0.85, 95% CI 0.68-1.06, P = 0.158). Eight studies documented the effects of glucocorticoids on gastrointestinal diseases, and meta-analysis showed no differences between the two groups (RR 1.12, 95% CI 0.83-1.50, P = 0.450).

CONCLUSION

The use of glucocorticoids can reduce the incidence of POAF. The subgroup analysis result showed that low-dose glucocorticoids were more effective than high-dose glucocorticoids in inhibiting POAF. The use of glucocorticoids in CABG alone can better inhibit the occurrence of POAF. The effects of glucocorticoids on infection and gastrointestinal injury were not statistically significant.

REVIEW REGISTRATION

PROSPERO, CRD42022304521.

Meta-Analysis: Shouldn't Prophylactic Corticosteroids be Administered During Cardiac Surgery with Cardiopulmonary Bypass?

Background

Corticosteroids can effectively inhibit systemic inflammation induced by cardiopulmonary bypass. Recently clinical trials and meta-analyses and current guidelines for cardiac surgery do not support corticosteroids prophylaxis during cardiac surgery because of an increase in myocardial infarction and no benefit for patients. The aim of this study is to determine whether specific corticosteroids dose ranges might provide clinical benefits without increasing myocardial infarction.

Methods

The PubMed, Web of Science, Embase, Clinical Trials, and Cochrane databases were searched for randomized controlled trials (RCTs) published before August 1, 2021.

Results

88 RCTs with 18,416 patients (17,067 adults and 1,349 children) were identified. Relative to placebo and high-dose corticosteroids, low-dose corticosteroids (≤20 mg/kg hydrocortisone) during adult cardiac surgery did not increase the risks of myocardial infarction (odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.43-2.17; p = 0.93). However, low-dose corticosteroids were associated with lower risks of atrial fibrillation (OR: 0.58, 95% CI: 0.44-0.76; p < 0.0001) and kidney injury (OR: 0.29, 95% CI: 0.09-0.96; p = 0.04). Furthermore, low-dose corticosteroids significantly shortened the mechanical ventilation times (mean difference [MD]: -2.74 h, 95% CI: -4.14, -1.33; p = 0.0001), intensive care unit (ICU) stay (MD: -1.48 days, 95% CI: -2.73, -0.22; p = 0.02), and hospital stay (MD: -2.29 days, 95% CI: -4.51, -0.07; p = 0.04).

Conclusion

Low-dose corticosteroids prophylaxis during cardiac surgery provided significant benefits for adult patients, without increasing the risks of myocardial infarction and other complications.

Model of Magnetic Particle Capture Under Physiological Flow Rates for Cytokine Removal During Cardiopulmonary Bypass

OBJECTIVE

The objective of this study is to design a physical model of a magnetic filtration system which can separate magnetic nanoparticle (MNP)-tagged cytokines from fluid at physiologically relevant flow rates employed during cardiopulmonary bypass (CPB) procedures.

METHODS

The Navier-Stokes equations for the pressure driven flow in the chamber and the quasistatic stray magnetic field produced by an array of permanent magnets were solved using finite element analysis in COMSOL Multiphysics for 2D and 3D representations of the flow chamber. Parameters affecting the drag and magnetic forces including flow chamber dimensions, high gradient magnet array configurations, and particle properties, were changed and evaluated for their effect on MNP capture.

RESULTS

Flow chamber dimensions which achieve appropriate flow conditions for CPB were identified, and magnetic force within the chamber decreased with increased chamber height. A magnetic "block" array produced the highest magnetic force within the chamber. Polymeric microparticles loaded with MNPs were shown to have increased particle capture with increased hydrodynamic diameter.

CONCLUSION

The model achieved a predicted efficiency up to 100% capture in a single-pass of fluid flowing at 1.75 L/min.

SIGNIFICANCE

This work is an important step in designing a magnetic flow chamber that can remove the magnetically tagged cytokines under high flow employed during CPB. Cytokines have been shown to stimulate the systemic inflammatory response (SIR) associated with CPB and are an established therapeutic target to mitigate the SIR. In the long term, this work aims to guide researchers in the more accurate design of magnetic separation systems.

Ubiquinol supplementation in elderly patients undergoing aortic valve replacement: biochemical and clinical aspects

Epidemiological data show a rise in the mean age of patients affected by heart disease undergoing cardiac surgery. Senescent myocardium reduces the tolerance to ischemic stress and there are indications about age-associated deficit in post-operative cardiac performance. Coenzyme Q10 (CoQ10), and more specifically its reduced form ubiquinol (QH), improve several conditions related to bioenergetic deficit or increased exposure to oxidative stress. This trial (Eudra-CT 2009-015826-13) evaluated the clinical and biochemical effects of ubiquinol in 50 elderly patients affected by severe aortic stenosis undergoing aortic valve replacement and randomized to either placebo or 400 mg/day ubiquinol from 7 days before to 5 days after surgery. Plasma and cardiac tissue CoQ10 levels and oxidative status, circulating troponin I, CK-MB (primary endpoints), IL-6 and S100B were assessed. Moreover, main cardiac adverse effects, NYHA class, contractility and myocardial hypertrophy (secondary endpoints) were evaluated during a 6-month follow-up visit. Ubiquinol treatment counteracted the post-operative plasma CoQ10 decline (p<0.0001) and oxidation (p=0.038) and curbed the post-operative increase in troponin I (QH, 1.90 [1.47-2.48] ng/dL; placebo, 4.03 [2.45-6.63] ng/dL; p=0.007) related to cardiac surgery. Moreover, ubiquinol prevented the adverse outcomes that might have been associated with defective left ventricular ejection fraction recovery in elderly patients.

Impact of Steroids on the Inflammatory Response after Ischemic Acute Kidney Injury in Rats

Inflammation plays a crucial role in acute kidney injury (AKI). The current study was designed to analyze the influence of prednisolone treatment on the inflammatory reaction during the first 96 h after AKI induction in a rat model. AKI was induced by unilateral clipping of the renal vessels. The treatment group received prednisolone 5 mg/kg s.c. daily. Infiltration rates of macrophages, leukocytes, and T-cells (24, 96 h) as well as plasma concentrations of the inflammatory markers intercellular adhesion molecule, interleukin-1 beta (IL-1β), IL-18, IL-6, and tumor necrosis factor-alpha (0, 6, 24, 96 h) were determined by fluorescence-activated cell sorting (FACS) analysis only. Ninety-six hours after AKI induction, the prednisolone group demonstrated significantly lower creatinine concentrations compared to the control group (P < 0.05). Twenty-four hours after induction of AKI, a significantly higher rate of infiltrating leukocytes was detectable with FACS analysis in the control group (P < 0.01) with a corresponding significantly higher rate of macrophages after 96 h (P < 0.01). IL-6 and IL-1β demonstrated a peak after 6 h with a significantly higher release in the control group (IL-6: P < 0.01; IL-1β: P < 0.05). In contrast to the control group, the prednisolone group demonstrated no further incline of IL-18 after 24 h. The results demonstrate the importance of stretching the observation period in an ischemia-reperfusion-induced AKI setting beyond the first 24 h. Despite the demonstrated protective effects of a continuous prednisolone application, it seems that this single anti-inflammatory agent will not be able to completely suppress the inflammatory response after an ischemia-reperfusion-induced AKI.

The Effect of Steroid Therapy on Postoperative Inflammatory Response after Endovascular Abdominal Aortic Aneurysm Repair

Objectives: Unexpected systemic inflammatory response with high fever and increase in C-reactive protein (CRP) occurred frequently after endovascular abdominal aortic aneurysm repair (EVAR). This excessive inflammatory response affects the postoperative course. We evaluated the effects of steroid on the postoperative inflammatory response after EVAR. Methods: Steroid therapy, intravenous infusion of methylprednisolone 1000 mg just after the anesthesia induction, was started since December 2012. After induction of the steroid therapy, 25 patients underwent EVAR with steroid therapy (Group S). These patients were compared with the 65 patients who underwent EVAR without steroid therapy (Group C) in white blood cell count (WBC), CRP and maximum body temperature (BT) on postoperative day 1-5. Results: There was no significant difference in age, female gender, operation time, maximum aneurysm diameter between the two groups. There was no postoperative infective complication in the both groups. WBC did not differ between the two groups; however, CRP was significantly suppressed in Group S than in Group C on POD 1, 3 and 5. Also BT was significantly lower in Group S than Group C on POD 1, 2 and 3. Conclusions: Steroid pretreatment before implantation of the stent graft reduces the early postoperative inflammatory response after EVAR, without increasing postoperative infection. (This is a translation of Jpn J Vasc Surg 2015; 24: 861-865.).

The efficacy of glucocorticoids for the prevention of atrial fibrillation, or length of intensive care unite or hospital stay after cardiac surgery: a meta-analysis

AIMS

cardiopulmonary bypass and cardiac surgery are associated with a significant systemic inflammatory response that has been suggested playing a causative role in the development of perioperative atrial fibrillation (POAF). The goal of this meta-analysis was to determine the efficacy of glucocorticoid prophylaxis in preventing POAF, or length of intensive care unite (ICU) or hospital stay.

METHODS

A systematic electronic database literature search of Cochrane controlled trials register (2013, issue 4) and MEDLINE (1966 to April, 2013) was conducted using specific search terms for all relevant articles. Including criteria were: randomized controlled clinical trials, participants were adults (≥18 years of age) undergoing cardiac surgery, evaluated glucocorticoid prophylaxis in cardiac surgery with adequately reported data on incidence of POAF, or length of ICU or hospital stay.

RESULTS

Forty-two randomized controlled trials involving 7621 participants were included in the meta-analysis. Overall, glucocorticoids prophylaxis significantly lowered participants' risk of developing POAF (Relative Risk [RR] 0.77; 95% confidence interval [CI] 0.66-0.90), P < 0.01), reduced length of ICU stay by 0.25 day (95% CI -0.40 to -0.10, P < 0.01). Glucocorticoid prophylaxis in cardiac surgery was not associated with increased all-cause of infection (RR 0.68; 95% CI 0.58-0.78, P < 0.01) and mortality (RR 0.75; 95% CI 0.52-1.08, P = 0.12).

CONCLUSIONS

Pooled evidence suggests that glucocorticoid prophylaxis may reduce the incidence of POAF. The beneficial effect on POAF is associated with reduced length of ICU and hospital stay, and infection rate.

Rationale and design of the steroids in cardiac surgery trial

BACKGROUND

Steroids may improve outcomes in high-risk patients undergoing cardiac surgery with the use of cardiopulmonary bypass (CBP). There is a need\ for a large randomized controlled trial to clarify the effect of steroids in such patients.

METHODS

We plan to randomize 7,500 patients with elevated European System for Cardiac Operative Risk Evaluation who are undergoing cardiac surgery with the use of CBP to methylprednisolone or placebo. The first coprimary outcome is 30-day all-cause mortality, and the most second coprimary outcome is a composite of death, MI, stroke, renal failure, or respiratory failure within 30 days. Other outcomes include a composite of MI or mortality at 30 days, new onset atrial fibrillation, bleeding and transfusion requirements, length of intensive care unit stay and hospital stay, infection, stroke, wound complications, gastrointestinal complications, delirium, postoperative insulin use and peak blood glucose, and all-cause mortality at 6 months.

RESULTS

As of October 22, 2013, 7,034 patients have been recruited into SIRS in 82 centers from 18 countries. Patient's mean age is 67.3 years, and 60.4% are male. The average European System for Cardiac Operative Risk Evaluation is 7.0 with 22.1% having an isolated coronary artery bypass graft procedure, and 66.1% having a valve procedure.

CONCLUSIONS

SIRS will lead to a better understanding of the safety and efficacy of prophylactic steroids for cardiac surgery requiring CBP.

Steroids for surgery during cardiopulmonary bypass in adults: a meta-analysis

STUDY OBJECTIVE

To evaluate the effect of steroid administration on myocardial infarction (MI), stroke, renal insufficiency, death, intensive care (ICU) length of stay (LOS) and hospital LOS of patients undergoing cardiopulmonary bypass (CPB).

DESIGN

Meta-analysis of parallel randomized controlled trials.

SETTING

University hospital.

MEAUREMENTS

A search was conducted in PubMed, EMBASE, MEDLINE(R) and the Cochrane Central Register of Controlled Trials of studies on adults undergoing surgery with CPB who received steroid administration. Effect size (risk ratio or mean difference) for MI, stroke, renal insufficiency, death, ICU LOS, and hospital LOS were evaluated.

MAIN RESULTS

48 RCTs published between 1977 and 2012 were retained for analysis. Steroids had no effect on the MI risk ratio (RR) 0.91 (95% confidence interval [CI] 0.63, 1.32); death at 30 days RR 0.84 (0.59, 1.20); stroke RR 0.92 (0.60, 1.42) or renal insufficiency RR 0.83 (0.52, 1.32). Administration of steroids reduced ICU LOS (P = 0.00001; I(2) 87.5%) and hospital LOS (P = 0.03; I(2) 81.1%). Metaregressions showed that duration of steroid administration was correlated with the reduction in ICU LOS (P = 0.0004) and hospital LOS (P < 0.00001).

CONCLUSIONS

Increasing the duration of steroid administration may reduce ICU and hospital LOS greater than increasing the dose.

Anti-inflammatory strategies to reduce acute kidney injury in cardiac surgery patients: a meta-analysis of randomized controlled trials

Acute kidney injury (AKI) after cardiac operations is a serious complication associated with postoperative mortality. Multiple factors contribute to AKI development, principally ischemia-reperfusion injury and inflammatory response. It is well proven that glucocorticoid administration, leukocyte filter application, and miniaturized extracorporeal circuits (MECC) modulate inflammatory response. We conducted a systematic review of randomized controlled trials (RCTs) in which one of these inflammatory system modulation strategies was used, with the aim to evaluate the effects on postoperative AKI. MEDLINE and Cochrane Library were screened through November 2011 for RCTs in which an inflammatory system modulation strategy was adopted. Included were trials that reported data about postoperative renal outcomes. Because AKI was defined by different criteria, including biochemical determinations, urine output, or dialysis requirement, we unified renal outcome as worsening renal function (WRF). We identified 14 trials for steroids administration (931 patients, WRF incidence [treatment vs. placebo]: 2.7% vs. 2.4%; OR: 1.13; 95% CI: 0.53-2.43; P = 0.79), 9 trials for MECC (947 patients, WRF incidence: 2.4% vs. 0.9%; OR: 0.47; 95% CI: 0.18-1.25; P = 0.13), 6 trials for leukocyte filters (374 patients, WRF incidence: 1.1% vs. 7.5%; OR: 0.18; 95% CI: 0.05-0.64; P = 0.008). Only leukocyte filters effectively reduced WRF incidence. Not all cardiopulmonary bypass-related anti-inflammatory strategies analyzed reduced renal damage after cardiac operations. In adult patients, probably other factors are predominant on inflammation in determining AKI, and only leukocyte filters were effective. Large multicenter RCTs are needed in order to better evaluate the role of inflammation in AKI development after cardiac operations.

Systematic review of 23-hour (outpatient) stay laparoscopic gastric bypass surgery

BACKGROUND

The laparoscopic Roux-en-Y gastric bypass (LRYGB) is generally considered the gold-standard bariatric procedure. It has a usual inpatient stay of 3 days. There have been few reports of gastric bypass patients being discharged within 23 hours of surgery, but its safety and feasibility has not been reviewed before. The aim of this study was to review the published literature on 23-hour stay post-LRYGB.

METHODS

Systematic search was performed in Medline, Embase, and Cochrane library using the medical subject heading terms "ambulatory surgical procedures" and "bariatric surgery" with further free text search and cross references. All articles on 23-hour LRYGB that described patient selection criteria, 23-hour discharge, complications, and readmissions were reviewed. Data were extracted by two independent reviewers.

RESULTS

There were no randomized controlled trials. Four cohort studies were included in this review. The patients age ranged from 14 to 70 years, mean body mass index ranged from 41.2 to 49.25, and the mean operative time ranged from 112.8 to 169 minutes. 1852/2201(84.14%) patients could be discharged within 23 hours. Forty-eight patients (2.18%) developed complications and 40 patients (1.82%) were readmitted. The commonest 30-day complications were anastomotic strictures (16), gastrointestinal bleeding (9), and internal hernias (9). Five patients developed anastomotic leak and 2 patients developed pulmonary embolism. Two patients died but neither was discharged after their bypass surgery.

CONCLUSION

There is a paucity of data regarding 23-hour discharge after LRYGB. The evidence suggests that it is feasible in selected patients. However, further studies are necessary to assess its safety and acceptability.

Prophylactic corticosteroids for cardiopulmonary bypass in adults

BACKGROUND

High-dose prophylactic corticosteroids are often administered during cardiac surgery. Their use, however, remains controversial, as no trials are available that have been sufficiently powered to draw conclusions on their effect on major clinical outcomes.

OBJECTIVES

The objective of this meta-analysis was to estimate the effect of prophylactic corticosteroids in cardiac surgery on mortality, cardiac and pulmonary complications.

SEARCH STRATEGY

Major medical databases (CENTRAL, MEDLINE, EMBASE, CINAHL and Web of Science) were systematically searched for randomised studies assessing the effect of corticosteroids in adult cardiac surgery. Database were searched for the full period covered, up to December 2009. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials comparing corticosteroid treatment to either placebo treatment or no treatment in adult cardiac surgery were selected. There were no restrictions with respect to length of the follow-up period. All selected studies qualified for pooling of results for one or more end-points.

DATA COLLECTION AND ANALYSIS

The processes of searching and selection for inclusion eligibility were performed independently by two authors. Also, quality assessment and data-extraction of selected studies were independently performed by two authors. The primary endpoints were mortality, cardiac and pulmonary complications. The main effect measure was the Peto odds ratio comparing corticosteroids to no treatment/placebo.

MAIN RESULTS

Fifty-four randomised studies, mostly of limited quality, were included. Altogether, 3615 patients were included in these studies. The pooled odds ratio for mortality was 1.12 (95% CI 0.65 to 1.92), showing no mortality reduction in patients treated with corticosteroids. The odds ratios for myocardial and pulmonary complications were 0.95, (95% CI 0.57 to 1.60) and 0.83 (95% CI 0.49 to 1.40), respectively. The use of a random effects model did not substantially influence study results. Analyses of secondary endpoints showed a reduction of atrial fibrillation and an increase in gastrointestinal bleeding in the corticosteroids group.

AUTHORS' CONCLUSIONS

This meta-analysis showed no beneficial effect of corticosteroid use on mortality, cardiac and pulmonary complications in cardiac surgery patients.

Protective effects of steroids in cardiac surgery: a meta-analysis of randomized double-blind trials

OBJECTIVE

Cardiac surgery and cardiopulmonary bypass (CPB) induce an acute inflammatory response contributing to postoperative morbidity. The use of steroids as anti-inflammatory agents in surgery using CPB has been tested in many trials and has been shown to have good anti-inflammatory effects but no clear clinical advantages for the lack of an adequately powered sample size. The aim of this study was to evaluate the effects of steroid treatment on mortality and morbidity after cardiac surgery.

DESIGN

A systematic meta-analysis of randomized double-blind trials (RDBs).

SETTING

A university hospital.

PARTICIPANTS

Adult patients who underwent cardiac surgery.

MEASUREMENTS AND MAIN RESULTS

A trial search was performed through PubMed and Cochrane databases from 1966 to January 2009. Among 104 clinical trials reviewed, 31 RDB trials (1,974 patients) were considered suitable to be analyzed. A quality assessment of the trials was performed using the Jadad score. The types of steroid used in these trials were methylprednisolone (51.4%), dexamethasone (34.3%), hydrocortisone (5.7%), prednisolone (2.9%), or a combination of methylprednisolone and dexamethasone (5.7%). Steroid prophylaxis provided a protective effect preventing postoperative atrial fibrillation (odds ratio = 0.56; confidence interval [CI] 0.44-0.72, p < 0.0001), reducing postoperative blood loss (mean difference = -204.2 mL; CI from -287.4 to -121 mL; p < 0.0001), and reducing intensive care unit (mean difference = -6.6 hours; CI from -10.5 to -2.7 hours, p = 0.0007) and overall hospital stay (mean difference = -0.8 days; CI from -1.4 to -0.2 days, p = 0.01). Steroid prophylaxis had no effect on postoperative mortality, mechanical ventilation duration, re-exploration for bleeding, and postoperative infection.

CONCLUSIONS

A systematic review of RDB trials reveals that steroid prophylaxis may reduce morbidity after cardiac surgery and does not increase the risk of postoperative infections.

Benefits and Risks of Corticosteroid Prophylaxis in Adult Cardiac Surgery

Background— Cardiopulmonary bypass and cardiac surgery are associated with a significant systemic inflammatory response that may increase postoperative complications. This meta-analysis assessed whether the benefits and risks of corticosteroid use were dose dependent in adult cardiac surgery.

Methods and Results— Randomized controlled trials of the use of corticosteroid prophylaxis in adult cardiac surgery (>18 years of age) requiring cardiopulmonary bypass were selected from MEDLINE (1966 to August 1, 2008), EMBASE (1988 to August 1, 2008), and the Cochrane controlled trials register without any language restrictions. A total of 3323 patients from 50 randomized controlled trials were identified and subject to meta-analysis. Corticosteroid prophylaxis reduced the risk of atrial fibrillation (25.1% versus 35.1%; number needed to treat, 10; relative risk, 0.74; 95% confidence interval [CI], 0.63 to 0.86; P <0.01) and length of stay in the intensive care unit (weighted mean difference, −0.37 days; 95% CI, −0.21 to −0.52; P <0.01) and hospital (weighted mean difference, −0.66 days; 95% CI, −0.77 to −1.25; P =0.03) compared with placebo. The use of corticosteroid was not associated with an increased risk of all-cause infection (relative risk, 0.93; 95% CI, 0.61 to 1.41; P =0.73), but hyperglycemia requiring insulin infusion after corticosteroid prophylaxis was common (28.2%; relative risk, 1.49; 95% CI, 1.11 to 2.01; P <0.01). No additional benefits were found on all outcomes beyond a total dose of 1000 mg hydrocortisone, and very high doses of corticosteroid were associated with prolonged mechanical ventilation.

Conclusions— Evidence suggests that low-dose corticosteroid is as effective as high-dose corticosteroid in reducing the risk of atrial fibrillation and duration of mechanical ventilation but with fewer potential side effects in adult cardiac surgery.

Use of warm priming solution in open heart surgery: its effects on hemodynamics and acute inflammation

Cardiac surgery causes an acute inflammatory response and organ damage. In this study, for the first time in the literature, we compared the effects of priming solutions at 20°C and 36°C on acute inflammatory markers and hemodynamic parameters. Forty patients were recruited and randomized into two groups, each consisting of 20 participants who underwent elective coronary artery bypass grafting operation. Groups were primed with the same solution at different temperatures. Hemodynamic parameters were recorded. Blood samples were drawn pre-operatively and at the 15th and 60th minutes of aortic cross-clamping and the 24th hour following surgery. Serum pre-albumin, α-1 antitrypsin, and tumor necrosis factor-α levels were determined. The groups were compared statistically. Both of the groups were comparable for mean aortic cross-clamping time and mean time for cardiopulmonary bypass. Mean blood pressure value was significantly lower and the mean amount of ephedrine hydrochloride used was significantly higher in the cold priming group. Spontaneous beating of the heart after removal of aortic cross-clamp significantly was more frequent in the warm priming group. A significant rise was observed in systemic inflammatory markers in the cold priming group. In our study, the lesser amount of ephedrine hydrochloride used and the higher frequency of spontneous beating of the heart in the warm priming group may be considered as improvements in hemodynamic status. Use of warm priming solution also induced a significant improvement in the acute inflammatory markers. We recommend the use of warm priming solution in open heart surgery.

Clinical benefit of steroid use in patients undergoing cardiopulmonary bypass: a meta-analysis of randomized trials

We sought to establish the efficacy and safety of prophylactic steroids in adult patients undergoing cardiopulmonary bypass (CPB). We performed a meta-analysis of randomized trials reporting the effects of prophylactic steroids on clinical outcomes after CPB. Outcomes examined were mortality, myocardial infarction, neurological events, new onset atrial fibrillation, transfusion requirements, postoperative bleeding, duration of ventilation, intensive care unit (ICU) stay, hospital stay, wound complications, gastrointestinal complications, and infectious complications. We included 44 trials randomizing 3205 patients. Steroids reduced new onset atrial fibrillation [relative risk (RR) 0.71, 95% confidence interval (CI) 0.59 to 0.87], postoperative bleeding [weighted mean difference (WMD) -99.6 mL, 95% CI -149.8 to -49.3], and duration of ICU stay (WMD -0.23 days, 95% CI -0.40 to -0.07). Length of hospital stay was also reduced (WMD -0.59 days, 95% CI -1.17 to -0.02), but this result was less robust. A trend towards reduction in mortality was observed (RR 0.73, 95% CI 0.45 to 1.18). Randomized trials suggest that perioperative steroids have significant clinical benefit in CPB patients by decreasing the risk of new onset atrial fibrillation, while results are encouraging for reducing bleeding, length of stay, and mortality. These data do not raise major safety concerns, however, a sufficiently powered trial is warranted to confirm or refute these findings.

Comparative Effectiveness of Methylprednisolone and Zero-balance Ultrafiltration on Inflammatory Response After Pediatric Cardiopulmonary Bypass

Studies have demonstrated that systemic inflammatory response syndrome (SIRS) remains one of the major causes of cardiopulmonary bypass (CPB)-associated organ injury during pediatric cardiac surgery. The purpose of this investigation was to compare the effectiveness of methylprednisolone (MP) and zero-balance ultrafiltration (ZBUF) on SIRS during pediatric CPB. Thirty infants undergoing open-heart surgeries were randomized to receive either MP in the priming solution (group M, n = 15) or ZBUF during CPB (group Z, n = 15). All the patients survived. Plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) were measured before CPB (T1), 5 min after the start of CPB (T2), at the termination of CPB (T3), the fourth hour (T4), and the eighth hour (T5) postoperatively. The results showed that the plasma concentrations of TNF-alpha in the Z group were significantly less than those in the M group at T4 and T5 (P < 0.05), and the plasma concentrations of IL-6 were significantly less than those in the M group at T4 (P < 0.05); the plasma concentrations of IL-8 in the Z group were significantly less than those in the M group at T5 (P < 0.05). There was no difference between two groups on the plasma concentrations of IL-10. The duration of postoperative mechanical ventilation was (9.6 +/- 0.8 h) in the M group and (7.8 +/- 0.4 h) in the Z group (P < 0.05). This study showed that application of ZBUF is more effective to decrease the level of inflammatory mediators including TNF-alpha, IL-6, and IL-8 than administration of MP after pediatric CPB.

Effect of cardiopulmonary bypass on cytokine network and myocardial cytokine production

BACKGROUND

In addition to the well-investigated proinflammatory cytokine expression, there is an ever increasing interest in the field of anti-inflammatory response to cardiopulmonary bypass (CPB). Evidence suggests that myocardium serves as an important source of cytokines during reperfusion and application of CPB. The effect of coronary artery bypass graft (CABG) without CPB on myocardial cytokine production has not as yet been investigated.

HYPOTHESIS

Cardiopulmonary bypass can cause long-term disturbance in pro- and anti-inflammatory cytokine balance, which may impede a patient's recovery following surgery. Therefore, the effect of CPB on the balance of the pro-/anti-inflammatory cytokines network and myocardial cytokine outflow was assessed throughout a longer period after surgery.

METHODS

Twenty patients were scheduled for CABG with CPB and 10 had off-pump surgery. Blood samples were taken before, during, and over the first week following surgery. Coronary sinus blood samples were collected during surgery. The ratio of pro- and anti-inflammatory cytokines was calculated and the cytokine concentration of peripheral and coronary sinus blood were compared in both groups.

RESULTS

Pro-/anti-inflammatory cytokine ratio decreased early after CPB followed by a delayed and marked increase. A more balanced ratio was present following off-pump surgery. Coronary sinus levels of certain cytokines exceeded the concentration of systemic blood in the course of CPB but not during off-pump operation.

CONCLUSION

Patients show pro-inflammatory predominant cytokine balance at a later stage after CPB in contrast to those without CPB. The heart produces a remarkable amount of cytokines only in the course of surgery with CPB.

Characterizing the Inflammatory Response to Cardiopulmonary Bypass in Children

Cardiopulmonary bypass is known to trigger a global inflammatory response. Age-dependent differences in the inflammatory response, the increased susceptibility to injury of immature organ systems, and the larger extracorporeal circuit to patient size ratio results in greater susceptibility of younger and smaller patients to the damaging effects of cardiopulmonary bypass. In this review the components of the inflammatory response to cardiopulmonary bypass are reviewed with special reference to the pediatric age group, including the age-specific impact on organ systems. In addition the current and evolving strategies to prevent, limit, and treat the inflammatory response to cardiopulmonary bypass in children are examined.

Pulse Low Dose Steroids Attenuate Post-Cardiopulmonary Bypass SIRS; SIRS I

BACKGROUND

Cardiopulmonary bypass (CPB) initiates inflammation that contributes to multiorgan dysfunction (SIRS). Steroids have been demonstrated to attenuate this response; however, resistance to use steroids remains because of potential adverse effects of the high doses used. This study examines a lower dose steroid protocol for safety and attenuation of SIRS.

METHODS

Sixty patients undergoing CPB were randomized to pulse low doses of methylprednisolone (250 mg given twice IV) or placebo in this RCT. Outcomes pertaining to hemodynamics, ventilator requirement, arrhythmia, and metabolic derangements were recorded. Post-operative glucose control and gastrointestinal prohylaxis was instituted in all patients.

RESULTS

IL-6 concentrations were lower in the steroid group at 4 and 8 h post-operatively (P < 0.0001). The steroid group demonstrated more normothermia (37.2 degrees C versus 37.6 degrees C, P = 0.002), better hemodynamic stability with less requirement for inotropes or vasopressors (0% versus 27.6%, P = 0.005), higher SVRIs (1840 versus 1340 DSm2/cm5, P = 0.002), and higher mean arterial pressures (79 versus 74 mmHg, P = 0.03). The steroid group had a shorter duration of intubation (7.7 versus 10.7 h, P = 0.02), a shorter length of ICU stay (1.0 versus 2.0 days, P = 0.03), and less blood loss (505 versus 690 ml, P = 0.04) with no difference in post-operative blood glucose levels or complications.

CONCLUSIONS

Patients undergoing cardiopulmonary bypass receiving low pulse dose steroids had better hemodynamics, shorter mechanical ventilation times, less blood loss, and required less time in the ICU compared to those receiving placebo. Therefore, this study demonstrates that prophylactic low dose steroids attenuate the SIRS response to CPB without resulting in any untoward side-effects.

Prostaglandin el attenuates impairment of cellular immunity after cardiopulmonary bypass

OBJECTIVE

It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB.

METHODS

Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity.

RESULTS

PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1.

CONCLUSION

PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.

Optimizing outcomes in bariatric surgery: outpatient laparoscopic gastric bypass

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is an effective treatment of severe obesity and one of the fastest growing surgical procedures in the United States.

METHODS

A single institution prospective database of patients undergoing outpatient laparoscopic (lap) RYGB over a 3-year period was reviewed. Study end points included hospital discharge within 23 hours, 30-day hospital readmission rate, early (<30 day) and late complication rates, and 30-day perioperative mortality. Variables assessed included surgeon experience, patient demographics, comorbidities, operative time, Roux limb pathway, intraoperative steroid bolus, and use of dexmedetomidine.

RESULTS

Two thousand consecutive patients undergoing outpatient lap RYGB were identified, and 84% (n = 1669) were discharged within 23 hours. Of these, 1.7% (n = 34) were readmitted within 30 days. The overall early and late complication rates were 1.9% (n = 38) and 4.3% (n = 86), respectively. The 30-day mortality rate was 0.1% (n = 2), and neither patient was discharged before death. Univariate analysis demonstrated surgeon experience (<50 cases), age (<56 years), body mass index (<60 kg/m), weight (400 lbs), comorbidities (<5), and intraoperative steroid bolus as predictive of successful outpatient discharge. Multivariate analysis revealed surgeon experience, comorbidities, body mass index, and steroid bolus as predictive variables.

CONCLUSIONS

These data suggest that outpatient lap RYGB can be performed with acceptable perioperative complication rates, hospital readmission, and mortality rates. Surgeon experience, careful patient selection, and the use of intraoperative steroid bolus predicted optimal patient outcomes.

Administration of steroids in pediatric cardiac surgery: impact on clinical outcome and systemic inflammatory response

Cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response. Pre-bypass steroid administration may modulate the inflammatory response, resulting in improved postoperative recovery. We performed a prospective study in the departments of cardiovascular surgery and pediatric intensive care medicine of two university hospitals that included 50 infants who underwent heart surgery. Patients received either prednisolone (30 mg/kg) added to the priming solution of the cardiopulmonary bypass circuit (steroid group) or no steroids (nonsteroid group). Clinical outcome parameters include therapy with inotropic drugs, oxygenation, blood lactate, glucose, and creatinine, and laboratory parameters of inflammation include leukocytes, C-reactive protein, and interleukin-8. Postoperative recovery (e.g., the number, dosage, and duration of inotropic drugs as well as oxygenation) was similar in patients treated with or without steroids when corrected for the type of cardiac surgery performed. After CPB, there was an inflammatory reaction, especially in patients with a long CPB time. Postoperative plasma levels of interleukin-8 were correlated with the duration of CPB time (r = 0.62, p < 0.001). Administration of steroids had no significant impact on the laboratory parameters of inflammation. Administration of prednisolone into the priming solution of the CPB circuit had no measurable influence on postoperative recovery and did not suppress the inflammatory response.

Can the use of methylprednisolone, vitamin C, or α-trinositol prevent cold-induced fluid extravasation during cardiopulmonary bypass in piglets?

OBJECTIVE

Hypothermic cardiopulmonary bypass is associated with capillary fluid leakage, resulting in edema and occasionally organ dysfunction. Systemic inflammatory activation is considered responsible. In some studies methylprednisolone has reduced the weight gain during cardiopulmonary bypass. Vitamin C and alpha-trinositol have been demonstrated to reduce the microvascular fluid and protein leakage in thermal injuries. We therefore tested these three agents for the reduction of cold-induced fluid extravasation during cardiopulmonary bypass.

METHODS

A total of 28 piglets were randomly assigned to four groups of 7 each: control group, high-dose vitamin C group, methylprednisolone group, and alpha-trinositol-group. After 1 hour of normothermic cardiopulmonary bypass, hypothermic cardiopulmonary bypass was initiated in all animals and continued to 90 minutes. The fluid level in the extracorporeal circuit reservoir was kept constant at the 400-mL level and used as a fluid gauge. Fluid needs, plasma volume, changes in colloid osmotic pressure in plasma and interstitial fluid, hematocrit, and total water contents in different tissues were recorded, and the protein masses and the fluid extravasation rate were calculated.

RESULTS

Hemodilution was about 25% after start of normothermic cardiopulmonary bypass. Cooling did not cause any further changes in hemodilution. During steady-state normothermic cardiopulmonary bypass, the fluid need in all groups was about 0.10 mL/(kg.min), with a 9-fold increase during the first 30 minutes of cooling (P <.001). This increased fluid need was due mainly to increased fluid extravasation from the intravascular to the interstitial space at a mean rate of 0.6 mL/(kg.min) (range 0.5-0.7 mL/[kg.min]; P <.01) and was reflected by increased total water content in most tissues in all groups. The albumin and protein masses remained constant in all groups throughout the study.

CONCLUSION

Pretreatment with methylprednisolone, vitamin C, or alpha-trinositol was unable to prevent the increased fluid extravasation rate during hypothermic cardiopulmonary bypass. These findings, together with the stability of the protein masses throughout the study, support the presence of a noninflammatory mechanism behind the cold-induced fluid leakage seen during cardiopulmonary bypass.

Current strategies for optimizing the use of cardiopulmonary bypass in neonates and infants

The use of cardiopulmonary bypass is still necessary for the repair of many congenital cardiac defects. However, exposure to cardiopulmonary bypass can still lead to major morbidity and sometimes mortality, especially in neonates and infants, despite a perfect surgical repair. Various research-based strategies have been used to minimize some of the complications related to cardiopulmonary bypass, including the systemic inflammatory response, hemodilution, and transfusion requirement. This overview provides some of the strategies that we use in our practice in applying cardiopulmonary bypass in the repair of congenital cardiac defects in neonates and infants.