Meta-analysis of the effects of preoperative renin-angiotensin system inhibitor therapy on major adverse cardiac events in patients undergoing cardiac surgery

Vasoplegic Syndrome and Anaesthesia: A Narrative Review

Vasoplegic syndrome (VS) is defined as low systemic vascular resistance, normal or high cardiac output, and resistant hypotension unresponsive to vasopressor agents and intravenous volume. VS is a frequently encountered complication in cardiovascular and transplantation surgery, burns, trauma, pancreatitis, and sepsis. The basis of the pathophysiology is associated with an imbalance of vasodilator and vasoconstrictive structure in vascular smooth muscle cells and is highly complex. The pathogenesis of VS has several mechanisms, including overproduction of iNO, stimulation of ATP-dependent K+ channels and NF-κB, and vasopressin receptor 1A (V1A-receptor) down-regulation. Available treatments involve volume and inotropes administration, vasopressin, methylene blue, hydroxocobalamin, Ca++, vitamin C, and thiamine, and should also restore vascular tone and improve vasoplegia. Other treatments could include angiotensin II, corticosteroids, NF-κB inhibitor, ATP-dependent K+ channel blocker, indigo carmine, and hyperbaric oxygen therapy. Despite modern advances in treatment, the mortality rate is still 30-50%. It is challenging for an anaesthesiologist to consider this syndrome's diagnosis and manage its treatment. Our review aims to review the diagnosis, predisposing factors, pathophysiology, treatment, and anaesthesia approach of VS during anaesthesia and to suggest a treatment algorithm.

The predictive value of high-sensitive troponin I for perioperative risk in patients undergoing gastrointestinal tumor surgery

BACKGROUND

The incidence of cardiovascular events in perioperative period of gastrointestinal tumor surgery cannot be ignored, and studies have shown that level of postoperative troponin is related to the postoperative risk of non-cardiac surgery. However, the relationship between pre-operative troponin levels and perioperative risk of gastrointestinal tumor surgery is unclear. Thus, we aimed to evaluate the value of high-sensitive cardiac troponin I (hs-cTnI) prior to gastrointestinal tumor surgery for perioperative risk assessment.

METHODS

In this retrospective cohort study, 1259 patients who underwent gastrointestinal tumor surgery and had been tested for hs-cTnI on admission within 7 days prior to surgery were retrospectively recruited from January 2018 to June 2020. The primary combined endpoint including in-hospital all-cause mortality, acute myocardial infarction, cardiac arrest or ventricular fibrillation and acute decompensated heart failure. The secondary endpoint included total hospital stay and requirement of intensive care treatment.

FINDINGS

Compared with patients with normal hs-cTnI, those with elevated hs-cTnI (> 0·028 ng/ml) were more likely to experience the combined endpoint (28·2% versus 2·7%, P < 0·001) and there was also an increasing rate of in mortality in elevated hs-cTnI group (2·4% versus 0·3%, P = 0·057). The length of total hospital stay was significantly longer in patients with elevated hs-cTnI (24·8 ± 16·3 versus 19·5 ± 7·9, P = 0·003) and the number of patients requiring intensive care treatment was also higher (22·6% versus 4·2%, P < 0·001). The area under the ROC curve assessing hs-cTnI in predicting in-hospital mortality was 0·787 [95% confidence interval (CI) 0·612-0·963, P = 0·015] and for combined endpoint was 0·822 [95% CI 0·766-0·879, P < 0·001]. Hs-cTnI > 0·028 ng/ml was associated with significantly higher cardiovascular event rate in patients with the revised cardiac index ≤ 1. The positive likelihood ratio of hs-cTnI (> 0·028 ng/ml) for predicting combined endpoint reaches 10.5 in patients with Lee index = 0. In multivariate logistic analyses, hs-cTnI was one of the best predictors for the combined endpoint [odds ratio (OR) 5·924 (95%CI: 2·869-12·233), P < 0·001].

INTERPRETATION

Hs-cTnI provides powerful prognostic information for patients undergoing gastrointestinal tumor surgery, and therefore provides reliable prognostic information incremental to revised cardiac index.

Developing an intervention to optimise the outcome of cardiac surgery in people with diabetes: the OCTOPuS pilot study

BACKGROUND

Cardiothoracic surgical outcomes are poorer in people with diabetes compared with those without diabetes. There are two important uncertainties in the management of people with diabetes undergoing major surgery: (1) how to improve diabetes management in the weeks leading up to an elective procedure and (2) whether that improved management leads to improved postoperative outcomes. The aim of this study was to develop and pilot a specialist diabetes team-led intervention to improve surgical outcomes in people with diabetes.

DESIGN

Open pilot feasibility study SETTING: Diabetes and cardiothoracic surgery departments, University Hospital Southampton NHS Foundation Trust PARTICIPANTS: Seventeen people with diabetes undergoing cardiothoracic surgery INTERVENTION: Following two rapid literature reviews, a prototype intervention was developed based on a previously used nurse-led outpatient intervention and tested.

PRIMARY OUTCOME

Feasibility and acceptability of delivering the intervention SECONDARY OUTCOMES: Biomedical data were collected at baseline and prior to surgery. We assessed how the intervention was used. In depth qualitative interviews with participants and healthcare professionals were used to explore perceptions and experiences of the intervention and how it might be improved.

RESULTS

Thirteen of the 17 people recruited completed the study and underwent cardiothoracic surgery. All components of the OCTOPuS intervention were used, but not all parts were used for all participants. Minor changes were made to the intervention as a result of feedback from the participants and healthcare professionals. Median (IQR) HbA1c was 10 mmol/mol (3, 13) lower prior to surgery than at baseline.

CONCLUSION

This study has shown that it is possible to develop a clinical pathway to improve diabetes management prior to admission. The clinical and cost-effectiveness of this intervention will now be tested in a multicentre randomised controlled trial in cardiothoracic centres across the UK.

TRIAL REGISTRATION

ISRCTN; ISRCTN10170306 . Registered 10 May 2018.

Meta-analysis of impact of renin-angiotensin system inhibitors on survival after transcatheter aortic valve implantation

INTRODUCTION

To determine whether renin-angiotensin system inhibitor (RASI) prescription is associated with better survival after transcatheter aortic valve implantation (TAVI), we performed the first meta-analysis of currently available studies.

EVIDENCE ACQUISITION

To identify all studies reporting impact of RASI prescription on survival after TAVI, we searched PubMed, Web of Science, Google Scholar, etc. through October 2019. We extracted adjusted (if unavailable, unadjusted) hazard ratios (HRs) with their confidence intervals (CIs) of midterm (up to ≥6-month) all-cause mortality for RASI prescription from each study and combined study-specific estimates using inverse variance-weighted averages of logarithmic HRs in the random-effects model.

EVIDENCE SYNTHESIS

We identified 13 eligible studies with a total of 26,132 TAVI patients and included them in the present meta-analysis. None was a randomized controlled trial, 5 were observational studies comparing patients with versus without RASI prescription (including 3 propensity score matched studies), and 8 were observational studies investigating RASI prescription as one of covariates. The primary meta-analysis of all studies demonstrated that RASI prescription was associated with significantly lower midterm mortality (HR=0.83; 95% CI: 0.76 to 0.92; P=0.0002). Although we identified significant funnel plot asymmetry (P=0.036 by the rank correlation test) suggesting publication bias, correcting for it using the trim-and-fill method did not substantially alter the result favoring RASI prescription (corrected HR=0.85; 95% CI: 0.76 to 0.95; P=0.004).

CONCLUSIONS

RASI prescription may be associated with better midterm survival after TAVI.

Strategies to Reduce Perioperative Nephrotoxicity

Postoperative acute kidney injury (AKI) is a common complication of surgery that is associated with significant adverse outcomes, including increased morbidity and mortality. The perioperative burden of AKI risk factors is complex and potentially large, including high-risk nephrotoxic medications, hypotension, hypovolemia, radiologic contrast, anemia, and surgery-specific factors. Understanding the pathogenesis, risk factors, and potential cumulative impact of perioperative nephrotoxic exposures is particularly important in the prevention and reduction of perioperative AKI. This review outlines the possible strategies to reduce perioperative nephrotoxicity and the development of postoperative AKI.

Impact of renin-angiotensin system inhibitors on outcomes after surgical or transcatheter aortic valve replacement. A meta-analysis

INTRODUCTION AND OBJECTIVES

To determine whether renin-angiotensin system inhibitor (RASi) prescription is associated with better outcomes after transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR).

METHODS

All comparative studies of RASi vs no RASi prescription in patients undergoing TAVI/SAVR were gathered from PubMed, Web of Science, and Google Scholar through August, 2019. We extracted hazard ratios (HRs) with their confidence intervals (CIs) for mortality from each study and combined study-specific estimates using inverse variance-weighted averages of logarithmic HRs in the random effects model.

RESULTS

We identified 6 eligible studies with a total of 21 390 patients (TAVI: 17 846; SAVR: 3544) and included them in the present meta-analysis. The 6 studies were observational comparative studies (including 3 propensity score matched and 3 cohort studies) of RASi vs no RASi prescription. The analysis demonstrated that RASi prescription was associated with significantly lower mortality in the whole group of patients undergoing aortic valve intervention (HR, 0.64; 95%CI, 0.47-0.88; P <.001). However, subgroup analysis suggested differences according to the selected therapy, with TAVI showing better mortality rates in the RASi group (HR, 0.67; 95%CI, 0.49-0.93) but not in the SAVR group (HR, 0.61; 95%CI, 0.29-1.30). No funnel plot asymmetry was identified, suggesting minimum publication bias. Sensitivity analyses sequentially eliminating dissimilar studies did not substantially alter the primary result favoring RASI prescription.

CONCLUSIONS

These findings suggest a mortality benefit of RASi in patients with AS treated with aortic valve replacement that might be particularly relevant following TAVI. Future randomized studies are warranted to confirm this relevant finding.

Associations between preoperative continuation of renin-angiotensin system inhibitor and cardiac surgery-associated acute kidney injury: a propensity score-matching analysis

BACKGROUND

Cardiac surgery-associated acute kidney injury (CSA-AKI) is associated with high risk for complications and mortality. Whether renin-angiotensin system (RAS) inhibitor should be continued or withdrawn in patients with long-term use before cardiac surgery has been lack of consensus.

METHODS

We performed this prospective observational cohort study and recruited cardiac surgery patients in the surgical intensive care units between 2000 and 2011. These patients were divided into users and non-users of RAS inhibitor. Propensity score matching and multivariable models were performed to investigate the association between renal outcome, mortality, and preoperative use of RAS inhibitor.

RESULTS

Preoperative use of RAS inhibitor was identified as the independent protective factor for AKI development (OR 0.41, 95% CI 0.23, 0.63), AKI severity (stage 3 vs. stage 1, OR 0.35, 95% CI 0.18, 0.69), and renal recovery (OR 3.41, 95% CI 1.84, 5.36). Nevertheless, there was no significant protective effect of RAS inhibitor on in-hospital dialysis, in-hospital mortality, and ensuing development of chronic kidney disease (CKD) after AKI. We created a prediction model of CSA-AKI and indicated that preoperative use of RAS inhibitor provided more protective effect in low-risk than high-risk population.

CONCLUSION

Preoperative use of RAS inhibitor was associated with less AKI development and severity, and higher renal recovery. Although more risk reduction of AKI development was shown in low-risk group by our prediction model, continued use of RAS inhibitor before cardiac surgery could provide protective effect in all patients.

Vasoplegic syndrome in cardiac surgery: Definitions, pathophysiology, diagnostic approach and management

Vasoplegic syndrome is a state of vasopressor resistant systemic vasodilation in the presence of a normal cardiac output. Its definition, pathophysiology, risk factors, diagnosis and therapeutic approach will be reviewed in this paper. It occurs frequently during cardiac surgery and is associated with high morbidity and mortality. A search in the LILACS, MEDLINE, and GOOGLE SCHOLAR databases was conducted to find the most relevant papers during the last 18 years. Prompt identification and diagnosis of patients at risk must be undertaken in order to implement an optimal therapeutic approach. This latter includes early treatment with vasopressors with different mechanisms of action.

U-shape association of serum albumin level and acute kidney injury risk in hospitalized patients

Background

While an association between hypoalbuminemia and increased risk of acute kidney injury (AKI) is well-established, the risk of AKI development and its severity among patients with elevated serum albumin is unclear. The aim of this study was to evaluate the risk of AKI in hospitalized patients stratified by various admission serum albumin levels.

Methods

This single-center retrospective study was conducted at a tertiary referral hospital. All adult hospitalized patients who had admission albumin levels available between January 2009 and December 2013 were enrolled. Admission albumin was categorized based on its distribution into six groups (≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL). The primary outcome was the incidence of hospital-acquired AKI (HAKI). Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission albumin strata using the albumin 3.5 to 3.9 mg/dL (lowest incidence of AKI) as the reference group.

Results

Of the total 9,552 studied patients, HAKI occurred in 1,556 (16.3%) patients. The incidence of HAKI among patients with admission albumin ≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL was 18.3%, 14.3%, 15.5%, 14.2%, 16.7%, and 26.0%, respectively. After adjusting for potential confounders, admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk of HAKI with odds ratios of 1.52 (95% CI 1.18–1.94) and 2.16 (95% CI 1.74–2.69), respectively. While stage 1 HAKI was significantly more frequent among patients with admission albumin ≥4.5 mg/dL (23.0% vs. 11.6%, P<0.001), incidence of stage 3 HAKI was higher in those with albumin ≤2.4 mg/dL (2.8% vs 0.3%, P<0.001).

Conclusion

Admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk for HAKI. Patients with admission albumin ≥4.5 mg/dL had HAKI with a lower intensity when compared with those who had admission albumin levels ≤2.4 mg/dL.

Admission calcium levels and risk of acute kidney injury in hospitalised patients

BACKGROUND

The risk of acute kidney injury (AKI) development among hospitalised patients with elevated calcium levels on admission remains unclear. The aim of this study was to assess the risk of AKI in hospitalised patients stratified by various admission serum calcium levels.

METHODS

This is a single-centre retrospective study conducted at a tertiary referral hospital. All hospitalised adult patients who had admission calcium levels available between 2009 and 2013 were enrolled. Admission calcium was categorised based on its distribution into six groups (≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9, and ≥10.0 mg/dL). The primary outcome was hospital-acquired AKI. Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission calcium strata using calcium levels of 8.0-8.4 mg/dL (lowest incidence of AKI) as the reference group.

RESULTS

A total of 12 784 patients were studied. Hospital-acquired AKI occurred in 1779 (13.9%) patients. The incidence of AKI among patients with admission calcium ≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL was 14.7%, 11.7%, 11.8%, 14.6%, 15.8% and 17.3%, respectively. After adjusting for potential confounders, admission calcium levels ≤7.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL were associated with increased risk of AKI with odds ratios of 1.36 (95%CI 1.08-1.72), 1.29 (95%CI 1.08-1.56), 1.38 (95%CI 1.14-1.68) and 1.51 (95%CI 1.19-1.91), respectively.

CONCLUSION

Admission hypocalcaemia and hypercalcaemia are associated with an increased risk for hospital acquired AKI. Patients with admission hypercalcaemia (≥10 mg/dL) carry a 1.51-fold risk for AKI development during hospitalisation.

Admission hyperphosphatemia increases the risk of acute kidney injury in hospitalized patients

BACKGROUND

Evidence on the association between elevated admission serum phosphate and risk of in-hospital acute kidney injury (AKI) is limited. The aim of this study was to assess the risk of AKI in hospitalized patients stratified by admission serum phosphate level.

METHODS

This is a single-center retrospective study conducted at a tertiary referral hospital. All hospitalized adult patients who had admission phosphate measurement available between January and December 2013 were enrolled. Admission phosphate was categorized into 6 groups (< 2.4, 2.4-2.9, 2.9-3.4, 3.4-3.9, 3.9-4.4, and ≥ 4.4 mg/dl). The primary outcome was in-hospital AKI occurring after hospital admission. Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission phosphate strata using the phosphate 2.4-2.9 mg/dl level (lowest incidence of AKI) as the reference group.

RESULTS

After excluding patients with end-stage renal disease (ESRD), without serum phosphate measurement, and those with AKI at time of admission, a total of 5036 patients were studied. Phosphate levels of < 2.4 and ≥ 4.4 mg/dl were found in 458 (9.1%) and 585 (11.6%) patients, respectively. In-hospital AKI occurred in 595 (11.8%) patients. The incidence of AKI among patients with admission phosphate < 2.4, 2.4-2.9, 2.9-3.4, 3.4-3.9, 3.9-4.4, and ≥ 4.4 mg/dl was 10.5, 9.5, 11.8, 10.0, 12.8, and 17.9%, respectively. After adjusting for potential confounders, admission serum phosphate > 4.4 mg/dl was associated with an increased risk of developing AKI with an odds ratio of 1.72 (95% confidence interval 1.20-2.47), whereas admission serum phosphate levels < 4.4 mg/dl were not associated with development of AKI during hospitalization.

CONCLUSION

Elevated admission phosphate is associated with an increased risk for in-hospital AKI.

Angiotensin Receptor Blockade Improves Cardiac Surgical Outcomes in Patients With Metabolic Syndrome

BACKGROUND

Perioperative use of angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEis) in patients undergoing cardiac operations remains controversial. The current practice of discontinuing renin-angiotensin-system inhibitors preoperatively may negate their beneficial effects in vulnerable populations, including patients with metabolic syndrome, who exhibit elevated renin-angiotensin system activity. We hypothesized that preoperative ARB use is associated with reduced incidence of postoperative complications, compared with ACEi or no drug, in patients with metabolic syndrome undergoing coronary artery bypass grafting.

METHODS

We used propensity matching to derive a cohort of 1,351 patients from 2,998 who underwent coronary artery bypass grafting based on preoperative use of ARBs, ACEis, or no renin-angiotensin-system inhibitors. Our primary end point was a composite of adverse events occurring within 30 days after the operation: new-onset atrial fibrillation/flutter, arrhythmia requiring cardioversion, perioperative myocardial infarction, acute renal failure, need for dialysis, cerebrovascular accidents, acute respiratory failure, or perioperative death.

RESULTS

At least one adverse event occurred in 524 (38.8%) of matched cohort patients (1,184 [39.6% of all patients]). Adjusting for European System for Cardiac Operative Risk Evaluation and metabolic syndrome in the matched cohort, preoperative use of ARBs was associated with a lower incidence of adverse events in patients with metabolic syndrome compared with preoperative use of no renin-angiotensin-system inhibitors (odds ratio, 0.43; 95% confidence interval, 0.19 to 0.99) or ACEis (odds ratio, 0.38; 95% confidence interval, 0.16 to 0.88).

CONCLUSIONS

Preoperative use of ARBs, but not ACEis, confers a benefit within 30 days after cardiac operations in patients with metabolic syndrome, suggesting potential efficacy differences of these drug classes in reducing cardiovascular morbidity and death in ambulatory vs surgical patients.

Incidence and risk factors of acute kidney injury following transcatheter aortic valve replacement

AIM

This study aimed to determine the incidence and risk factors of acute kidney injury (AKI) following transcatheter aortic valve replacement (TAVR).

METHODS

We included all adult patients undergoing TAVR for aortic stenosis from 1 January 2008 to 30 June 2014 at a tertiary referral hospital. AKI was defined based on Kidney Disease: Improving Global Outcomes criteria. We performed a multivariate logistic regression to identify factors associated with post-procedural AKI occurrence.

RESULTS

Three hundred eighty-six patients met the inclusion criteria, of which 106 (28%) developed AKI. In multivariate analysis, AKI development was independently associated with a transapical approach (odds ratio (OR), 2.81; 95% confidence interval (CI), 1.72-4.65 compared with transfemoral approach) and the need for an intra-aortic balloon pump (OR, 9.11; 95% CI, 1.77-68.29). Higher baseline renal function (OR, 0.78 per 10 mL/min per 1.73 m² increment in glomerular filtration rate; 95% CI, 0.68-0.87) was significantly associated with a decreased risk of AKI. After adjustment for the Society of Thoracic Surgeons' risk score, post-procedural AKI development remained significantly associated with an increased in-hospital (OR, 4.74; 95% CI, 1.39-18.48) and 6-month mortality (OR, 4.66; 95% CI, 2.32-9.63).

CONCLUSION

In a cohort of patients undergoing TAVR for aortic stenosis, AKI commonly occurred and was significantly associated with increased mortality. Baseline renal function, procedure approach and the need for circulatory support were important predictive factors for post-procedural AKI occurrence.

AKI after Transcatheter or Surgical Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) for patients with symptomatic severe aortic stenosis who are at high risk of perioperative mortality. Previous studies showed increased risk of postoperative AKI with TAVR, but it is unclear whether differences in patient risk profiles confounded the results. To conduct a propensity-matched study, we identified all adult patients undergoing isolated aortic valve replacement for aortic stenosis at Mayo Clinic Hospital in Rochester, Minnesota from January 1, 2008 to June 30, 2014. Using propensity score matching on the basis of clinical characteristics and preoperative variables, we compared the postoperative incidence of AKI, defined by Kidney Disease Improving Global Outcomes guidelines, and major adverse kidney events in patients treated with TAVR with that in patients treated with SAVR. Major adverse kidney events were the composite of in-hospital mortality, use of RRT, and persistent elevated serum creatinine ≥200% from baseline at hospital discharge. Of 1563 eligible patients, 195 matched pairs (390 patients) were created. In the matched cohort, baseline characteristics, including Society of Thoracic Surgeons risk score and eGFR, were comparable between the two groups. Furthermore, no significant differences existed between the TAVR and SAVR groups in postoperative AKI (24.1% versus 29.7%; P=0.21), major adverse kidney events (2.1% versus 1.5%; P=0.70), or mortality >6 months after surgery (6.0% versus 8.3%; P=0.51). Thus, TAVR did not affect postoperative AKI risk. Because it is less invasive than SAVR, TAVR may be preferred in high-risk individuals.

Admission hyperuricemia increases the risk of acute kidney injury in hospitalized patients(.)

Background

The association between elevated admission serum uric acid (SUA) and risk of in-hospital acute kidney injury (AKI) is limited. The aim of this study was to assess the risk of developing AKI in all hospitalized patients with various admission SUA levels.

Methods

This is a single-center retrospective study conducted at a tertiary referral hospital. All hospitalized adult patients who had admission SUA available from January 2011 through December 2013 were analyzed in this study. Admission SUA was categorized based on its distribution into six groups (<3.4, 3.4–4.5, 4.5–5.8, 5.8–7.6, 7.6–9.4 and >9.4 mg/dL). The primary outcome was in-hospital AKI occurring after hospital admission. Logistic regression analysis was performed to obtain the odds ratio (OR) of AKI of various admission SUA levels using the most common SUA level range (5.8–7.6 mg/dL) as the reference group.

Results

Of 1435 patients enrolled, AKI occurred in 263 patients (18%). The incidence of AKI and need for dialysis was increased in patients with higher admission SUA levels. After adjusting for potential confounders, SUA >9.4 mg/dL was associated with an increased risk of developing AKI, with ORs of 1.79 [95% confidence interval (CI) 1.13–2.82]. Conversely, admission SUA <3.4 and 3.4–4.5 mg/dL were associated with a decreased risk of developing AKI, with ORs of 0.38 (95% CI 0.17–0.75) and 0.50 (95% CI 0.28–0.87), respectively.

Conclusions

Elevated admission SUA was associated with an increased risk for in-hospital AKI.