Min Hur

Risk Factors for Acute Kidney Injury after Congenital Cardiac Surgery in Infants and Children: A Retrospective Observational Study

Acute kidney injury (AKI) after pediatric cardiac surgery is associated with high morbidity and mortality. Modifiable risk factors for postoperative AKI including perioperative anesthesia-related parameters were assessed. The authors conducted a single-center, retrospective cohort study of 220 patients (aged 10 days to 19 years) who underwent congenital cardiac surgery between January and December 2012. The incidence of AKI within 7 days postoperatively was determined using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Ninety-two patients (41.8%) developed AKI and 18 (8.2%) required renal replacement therapy within the first postoperative week. Among patients who developed AKI, 57 patients (25.9%) were KDIGO stage 1, 27 patients (12.3%) were KDIGO stage 2, and eight patients (3.6%) were KDIGO stage 3. RACHS-1 (Risk-Adjusted classification for Congenital Heart Surgery) category, perioperative transfusion and fluid administration as well as fluid overload were compared between patients with and without AKI. Multivariable logistic regression analyses determined the risk factors for AKI. AKI was associated with longer hospital stay or ICU stay, and frequent sternal wound infections. Younger age (<12 months) [odds ratio (OR), 4.01; 95% confidence interval (CI), 1.77–9.06], longer cardiopulmonary bypass (CPB) time (OR, 2.45; 95% CI, 1.24–4.84), and low preoperative hemoglobin (OR, 2.40; 95% CI, 1.07–5.40) were independent risk factors for AKI. Fluid overload was not a significant predictor for AKI. When a variable of hemoglobin concentration increase (>3 g/dl) from preoperative level on POD1 was entered into the multivariable analysis, it was independently associated with postoperative AKI (OR, 6.51; 95% CI, 2.23–19.03 compared with no increase). This association was significant after adjustment with patient demographics, medication history and RACHS-1 category (hemoglobin increase >3g/dl vs. no increase: adjusted OR, 6.94; 95% CI, 2.33–20.69), regardless of different age groups and cyanotic or non-cyanotic heart disease. Prospective trials are required to evaluate whether correction of preoperative anemia and prevention of hemoconcentration may ameliorate postoperative AKI in patients who underwent congenital cardiac surgery.

The effect of early goal-directed therapy for treatment of severe sepsis or septic shock: A systemic review and meta-analysis

Purpose: To assess the effects of early goal‐directed therapy (EGDT) on reducing mortality compared with conventional management of severe sepsis or septic shock. Materials and methods: We included a systemic review, using the Medline and EMBASE. Seventeen randomized trials with 5765 patients comparing EGDT with usual care were included. Results: There were no significant differences in mortality between EGDT and control groups (relative risk [RR], 0.89; 95% confidence interval [CI], 0.79‐1.00), with moderate heterogeneity (I2 = 56%). The EGDT was associated with lower mortality rates when the mortality rate of the usual care group was greater than 30% (12 trials; RR, 0.83; 95% CI, 0.72‐0.96), but not when the mortality rate in the usual care group was less than 30% (5 trials; RR, 1.03; 95% CI, 0.92‐1.16). The mortality benefit was seen only in subgroup of population analyzed between publication of the 2004 and 2012 Surviving Sepsis Campaign guidelines, but not before and after these publications. Conclusion: This meta‐analysis was heavily influenced by the recent addition of the trio of trials published after 2014. The results of the recent trio of trials may be biased due to methodological issues. This includes lack of blinding by incorporating similar diagnostic and therapeutic interventions as the original EGDT trial.

Preoperative aspirin use and acute kidney injury after cardiac surgery: A propensity-score matched observational study

Background The association between preoperative aspirin use and postoperative acute kidney injury (AKI) in cardiovascular surgery is unclear. We sought to evaluate the effect of preoperative aspirin use on postoperative AKI in cardiac surgery. Methods A total of 770 patients who underwent cardiovascular surgery under cardiopulmonary bypass were reviewed. Perioperative clinical parameters including preoperative aspirin administration were retrieved. We matched 108 patients who took preoperative aspirin continuously with patients who stopped aspirin more than 7 days or did not take aspirin for the month before surgery. The parameters used in the matching included variables related to surgery type, patient’s demographics, underlying medical conditions and preoperative medications. Results In the first seven postoperative days, 399 patients (51.8%) developed AKI, as defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and 128 patients (16.6%) required hemodialysis. Most patients took aspirin 100 mg once daily (n = 195, 96.5%) and the remaining 75 mg once daily. Multivariable analysis showed that preoperative maintenance of aspirin was independently associated with decreased incidence of postoperative AKI (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.21–0.98, P = 0.048; after propensity score matching: OR 0.39, 95% CI 0.22–0.67, P = 0.001). Preoperative maintenance of aspirin was associated with less incidence of AKI defined by KDIGO both in the entire and matched cohort (n = 44 [40.7%] vs. 69 [63.9%] in aspirin and non-aspirin group, respectively in matched sample, relative risk [RR] 0.64, 95% CI 0.49, 0.83, P = 0.001). Preoperative aspirin was associated with decreased postoperative hospital stay after matching (12 [9–18] days vs. 16 [10–25] in aspirin and non-aspirin group, respectively, P = 0.038). Intraoperative estimated or calculated blood loss using hematocrit difference and estimated total blood volume showed no difference according to aspirin administration in both entire and matched cohort. Conclusions Preoperative low dose aspirin administration without discontinuation was protective against postoperative AKI defined by KDIGO criteria independently in both entire and matched cohort. Preoperative aspirin was also associated with decreased hemodialysis requirements and decreased postoperative hospital stay without increasing bleeding. However, differences in AKI and hospital stay were not associated with in-hospital mortality.

Pharmacological interventions for protecting renal function after cardiac surgery: a Bayesian network meta-analysis of comparative effectiveness.

Many drugs have been investigated as potentially protective of renal function after cardiac surgery. However, their comparative effectiveness has not been established. We performed an arm‐based hierarchical Bayesian network meta‐analysis including 95 randomised controlled trials with 28,833 participants, which allowed us to compare some agents not previously compared directly. Renal outcomes, including: the incidence of postoperative renal dysfunction and haemodialysis; serum creatinine level at 24 hours postoperatively; all‐cause mortality; and length of hospital and ICU stay, were compared. Exploratory meta‐regression was conducted for potential effect modifiers. A random effects model was selected according to the evaluation of model fit by deviance information criteria. Atrial natriuretic peptide (odds ratio (95%CrI) 0.28 (0.17–0.48); moderate‐quality evidence), B‐type natriuretic peptide, dexmedetomidine, levosimendan and N‐acetyl cysteine significantly decreased the rate of postoperative renal dysfunction compared with placebo. Atrial natriuretic peptide (OR (95%CrI) 0.24 (0.10–0.58); low‐quality evidence), B‐type natriuretic peptide, and dexamethasone significantly decreased the need for haemodialysis. Levosimendan significantly decreased mortality, OR (95%CrI) 0.49 (0.27–0.91); low‐quality evidence). The benefit of atrial natriuretic peptide was still apparent when baseline renal function was normal. None of the potential effect modifiers were significantly correlated with our renal outcomes. Atrial natriuretic peptide was ranked best regarding renal dysfunction, haemodialysis and length of hospital stay. Levosimendan was ranked best regarding mortality and ICU stay. However, our results should be interpreted cautiously given the assumptions made about transitivity and consistency.

Acute kidney injury in parturients with severe preeclampsia

We read with interest the study by Mazda et al. [1] regarding postoperative acute kidney injury (AKI) in parturients with severe preeclamsia. We would like to discuss the clinical implication of the study. First, the effect of hydroxyl ethyl starch (HES) administration was not evaluated fully. Clinical outcomes other than AKI were not compared with a control group. Although not clearly shown, the number of patients with proteinuria or elevated serum creatinine seems to be very small. The incidence of AKI and the impact of HES on AKI may be different in the more selected patients with severe preeclampsia with renal dysfunction [2]. Second, the serum creatinine measurement may not be a reliable estimation of glomerular filtration rate (GFR) in these parturients [3]. Delivery itself and different oral intakes after surgery may influence serum creatinine and following creatinine after delivery may not be accurate. GFR increases up to 50% during pregnancy and continue at levels 20% above normal at postpartum week [4]. Diagnosis of AKI in these patients using other measurement of GFR or more sensitive biomarkers may be required.

Comparison between general, spinal, epidural, and combined spinal-epidural anesthesia for caesarean delivery: a network meta-analysis

BACKGROUND This study is a network meta-analysis to compare maternal and fetal outcomes associated with four different anesthetic techniques for cesarean delivery. METHODS An arm-based, random-effects frequentist network meta-analysis was performed. A random effect model was selected considering deviance information criteria. Randomized trials reporting the following outcomes were included: Apgar score at 1- or 5-min; umbilical arterial and venous pH; umbilical arterial pH <7.2; and neonatal score at 2-4 hours. Loop-specific heterogeneity was evaluated by risk of odds ratio and τ2. Quality of evidence was assessed using the GRADE approach. RESULTS Data from 46 randomized trials including 3689 women contributed to the study. There were significant differences in Apgar score ≤6 at 1 min between spinal versus general anesthesia (odds ratio 0.27, 95% confidence interval [CI] 0.13 to 0.55: moderate quality evidence) and Apgar scores at 1- and 5-min, favoring spinal anesthesia. Umbilical venous pH associated with epidural anesthesia was significantly higher than that with general anesthesia (mean difference 0.010, 95% CI 0.001 to 0.020: moderate quality evidence) or spinal anesthesia. Spinal anesthesia was ranked best for Apgar score ≤6 at 1-min (SUCRA=89.8), Apgar score at 1-min (SUCRA=80.4) and 5-min (SUCRA=90.5). Epidural anesthesia was ranked highest for umbilical venous pH (SUCRA=87.4) and neonatal score (SUCRA=79.3). CONCLUSIONS Spinal and epidural anesthesia were ranked high regarding Apgar scores and epidural anesthesia was ranked high regarding umbilical venous pH, but the results were based on small heterogeneous studies with high or unclear risks of bias.

Association between AKI and all-cause mortality after EVAR

1. Minami K, Sugiyama Y, Iida H. A retrospective observational cohort study investigating the association between acute kidney injury and all-cause mortality among patients undergoing endovascular repair of abdominal aortic aneurysms. J Anesth. 2017. doi: 10.1007/s00540-017-2380-9 2. Zettervall SL, Soden PA, Deery SE, Ultee K, Shean KE, Shuja F, Amdur RL, Schermerhorn ML. Comparison of renal complications between endografts with suprarenal and infrarenal fixation. Eur J Vasc Endovasc Surg. 2017;54:5–11. 3. Kellum JA, Zarbock A, Nadim MK. What endpoints should be used for clinical studies in acute kidney injury? Intensive Care Med. 2017;43:901–3. To the Editor:

Acute kidney injury after pediatric liver transplantation

1. Hamada M, Matsukawa S, Shimizu S, Kai S, Mizota T. Acute kidney injury after pediatric liver transplantation: incidence, risk factors, and association with outcome. J Anesth. 2017. doi:10.1007/ s00540-017-2395-2 2. Lex DJ, Toth R, Cserep Z, Alexander SI, Breuer T, Sapi E, Szatmari A, Szekely E, Gal J, Szekely A. A comparison of the systems for the identification of postoperative acute kidney injury in pediatric cardiac patients. Ann Thorac Surg. 2014;97:202–10. 3. Selewski DT, Cornell TT, Heung M, Troost JP, Ehrmann BJ, Lombel RM, Blatt NB, Luckritz K, Hieber S, Gajarski R, Kershaw DB, Shanley TP, Gipson DS. Validation of the KDIGO acute kidney injury criteria in a pediatric critical care population. Intensive Care Med. 2014;40:1481–8. 4. Williams GD, Bratton SL, Ramamoorthy C. Factors associated with blood loss and blood product transfusions: a multivariate analysis in children after open-heart surgery. Anesth Analg. 1999;89:57–64. 5. Park MH, Shim HS, Kim WH, Kim HJ, Kim DJ, Lee SH, Kim CS, Gwak MS, Kim GS. Clinical risk scoring models for prediction of acute kidney injury after living donor liver transplantation: a retrospective observational study. PLoS One. 2015;10:e0136230. 6. Eaton MP. Antifibrinolytic therapy in surgery for congenital heart disease. Anesth Analg. 2008;106:1087–100. To the Editor: