Tomohiko Suemori

Cerebral oxygen saturation and tissue hemoglobin concentration as predictive markers of early postoperative outcomes after pediatric cardiac surgery

Near‐infrared spectroscopy (NIRS) provides an assessment of cerebral oxygenation and tissue hemoglobin concentration.

Impairment of leukocyte deformability in patients undergoing esophagectomy

Impaired deformability might contribute to the accumulation of activated leukocytes within pulmonary microcapillaries, leading to acute lung injury. The purpose of our study was to investigate changes in leukocyte deformability during periods of inflammation after esophagectomy. The study group comprised 20 patients who underwent esophagectomy. Changes in leukocyte deformability were investigated by examining filtration through a silicon microchannel, which simulated human pulmonary microcapillaries. Changes in the neutrophil cytoskeleton were investigated by measuring neutrophil F-actin assembly. The severity of patient clinical outcome was evaluated by the lung injury score. Leukocyte filtration through the microchannel was significantly weaker in esophagectomy patients than in healthy subjects (p<0.01). After esophagectomy, filtration was further impaired compared with preoperative values (p<0.05). The neutrophil F-actin content was higher in patients than in controls (p<0.01), and increased after esophagectomy compared with preoperative values (p<0.01). We concluded that circulating leukocytes showed reduced deformability and appeared to be sequestered within microcapillaries after esophagectomy. Changes in neutrophil cytoskeleton were considered to be responsible for the reduced deformability. Leukocyte accumulation within pulmonary microcapillaries might be related to the pathogenesis of lung injury after esophagectomy.

242: LOWER SERUM ALBUMIN AT ICU ADMISSION PREDICTS POSTOPERATIVE AKI FOLLOWING PEDIATRIC CARDIAC SURGERY

Critical Care Medicine • Volume 46 • Number 1 (Supplement) www.ccmjournal.org Learning Objectives: Acute kidney injury (AKI) is recognized as a complication after cardiac surgery in adults and children. There has been an effort to identify AKI biomarkers, with the hope of facilitating timely prophylactic and/or early therapeutic interventions. We reported the usefulness of urine albumin as AKI biomarker. However, little is known about relationship between AKI after heart surgery and serum albumin level. Methods: To test the utility of serum albumin at ICU admission as a predictor for AKI in children following cardiac surgery. Prospective observational study. Setting: Singlecenter, university affiliated tertiary teaching hospital. Children younger than 18 years old admitted to intensive care unit (ICU) after cardiac surgery between July 2010 and July 2012. Our institutional review board approved the current study protocol. Children younger than 18 years old admitted to ICU following cardiac surgery from July 2010 to July 2012 were included. Serum albumin and blood samples were measured when the patients admitted to ICU. Age, gender, body weight, RACHS-1 category, vital signs and blood tests for 24 hours from ICU admission were collected. Outcomes such as mortality, cardiovascular events, duration of mechanical ventilation, or duration of ICU stay were also collected. Pediatric RIFLE (pRIFLE) criteria were used to define severity of AKI. Data were analyzed in order to investigate a relationship between serum Albumin and AKI. Results: Our data identified 359 children younger than 18 years of age. Their median age was 18 months [interquartile range (IQR);6–53 months], body weight was 8.8 kg (IQR; 5.4–14.5) and gender male was 201/359(56.1%). On pRIFLE criteria, Normal(N) was 125, Risk(R) was 157, Injury(I) was 39, and Failure(F) was 38. Their median albumin at ICU adimission was 4.6 g/dL (IQR; 4.3– 4.8) and albumin at ICU admission in Failure category by pRIFLE was significantly lower than those in other categories [4.2 (IQR; 3.9–4.8) vs 4.9 (IQR; 4.6–5.3), p < 0.0001]. The AUC of albumin at ICU admission for Failure on pRIFLE was 0.78. There were 15 children (4.2%) who required peritoneal dialysis (PD) as a renal replacement therapy and Alb at ICU admission in PD patients were significantly lower than those in non-PD patients [4.4 (IQR; 4.0–4.8) vs 4.9 (4.8–4.9), p = 0.041]. Conclusions: Serum albumin at ICU admission could be an early marker of AKI in children following cardiac surgery.

High Ionized Calcium Concentration Is Associated With Prolonged Length of Stay in the Intensive Care Unit for Postoperative Pediatric Cardiac Patients

OBJECTIVE There has been controversy regarding the beneficial effects of calcium on myocardial contractility and the harmful effects on myocardial cells, especially in children. The aim of this study was to investigate an association between ionized calcium concentration (iCa) and outcomes for pediatric patients after cardiac surgery. DESIGN A retrospective, single-center study from May 2013 to December 2014. SETTING Referral high-volume pediatric cardiac center in a tertiary teaching hospital. PATIENTS Patients <72 months old with congenital heart disease who underwent palliative or definitive surgery. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS The association between pH-corrected iCa within 24 hours after surgery and intensive care unit (ICU) length of stay (ILOS) was defined as the primary outcome. The highest iCa (iCamax), lowest iCa (iCamin), and time-weighted average iCa (iCaave) were stratified and compared with the outcomes. The authors reviewed 5,468 ionized calcium measurements from 357 consecutive pediatric patients during the study period. One patient died at postoperative day 34 in the ICU. Significant differences in ILOS were observed among patients after cardiopulmonary bypass (CPB) according to iCaave, iCamax, and iCamin but not among patients without CPB. Patients with CPB and an iCaave value of 1.31-to-1.40 mmol/L, 1.41-to-1.50 mmol/L, 1.51-to-1.60 mmol/L, and >1.60 mmol/L stayed in the ICU for 7 (interquartile range [IQR] 4-10) days, 8 (IQR 6-16) days, 10 (IQR 8-14) days, and 19 (IQR 12-38) days, respectively, which was significantly longer than the ILOS of 5 (4-8) days for patients with an iCaave of 1.21-to-1.30 mmol/L. Even after adjustment for other predictors of ILOS using multivariable analyses, there were significant relationships of ILOS with iCaave and iCamin values of >1.50 mmol/L among patients with CPB. CONCLUSIONS Higher iCa within 24 hours after congenital cardiac surgery using CPB was independently associated with longer LOS in the ICU.