Preoperative low muscle mass and early postoperative outcomes in children undergoing living donor liver transplantation: A retrospective study.

Low skeletal muscle mass may develop in children with end-stage liver disease, affecting postoperative outcomes. We retrospectively investigated whether preoperative low muscle mass was associated with early postoperative outcomes in pediatric patients undergoing living donor liver transplantation (LDLT). Electronic medical records of children (age below 12 y) who underwent LDLT between February 1, 2007, and January 31, 2018, were reviewed. The cross-sectional areas of psoas, quadratus lumborum, and erector spinae muscles at the level of fourth-fifth lumbar intervertebral disks were measured using abdominal CT images, divided by the square of the height and were added to obtain the total skeletal muscle index (TSMI). The patients were divided into two groups according to the median TSMI in the second quintile (1859.1 mm 2 /m 2 ). Complications in the early postoperative period (within 30 d after surgery) classified as Clavien-Dindo grade 3 or higher were considered major complications. Logistic regression analyses were performed to determine the association between preoperative low muscle mass and early postoperative outcomes. In the study population of 123 patients (median age, 14 mo; range, 8-38 mo) who underwent LDLT, 29% and 71% were classified in the low (mean TSMI, 1642.5 ± 187.0 mm 2 /m 2 ) and high (mean TSMI 2188.1 ± 273.5 mm 2 /m 2 ) muscle mass groups, respectively. The rates of major complications, mechanical ventilation >96 hours, intensive care unit stay >14 days, hospital stay >30 days, and in-hospital mortality were not significantly different between the 2 groups. Additionally, adverse outcomes according to pediatric end-stage liver disease scores and sex were not significantly different between the 2 groups. In conclusion, preoperative low muscle mass defined by TSMI was not associated with early postoperative outcomes in pediatric patients undergoing LDLT.

Association Between Preoperative Sarcopenia and Early Postoperative Outcomes in Pediatric Patients Undergoing Total Correction of Tetralogy of Fallot: A Retrospective Cohort Study.

OBJECTIVES: To identify the association between preoperative low muscle mass and early postoperative outcomes in pediatric patients undergoing total correction of tetralogy of Fallot (TOF). DESIGN: A retrospective cohort study. SETTING: A single university hospital in Seoul, South Korea. PARTICIPANTS: Pediatric patients (≤3 years) who underwent total correction of TOF between May 2008 and February 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cross-sectional areas of the pectoralis and erector spinae muscles were measured using preoperative chest computed tomography (CT) scans, and adjusted to body surface area to define muscle mass index. The patients were divided into sarcopenia, presarcopenia, and no sarcopenia groups based on cutoff values determined using the mean and SD of the muscle mass index in the third z-weight quintile. Of a total of 330 patients included in the final analysis, 13 were associated with the sarcopenia group, 57 in the presarcopenia group, and 260 in the no sarcopenia group. The sarcopenia group exhibited a higher incidence of major adverse events than the presarcopenia and no sarcopenia groups, respectively (38% v 25% v 18%; p = 0.033). Logistic regression analyses revealed that only younger age at the time of surgery was significantly associated with major adverse events (odds ratio 0.82; 95% CI 0.72-0.94, p = 0.003). CONCLUSIONS: The incidence of sarcopenia, as assessed by preoperative chest CT, was low in pediatric patients undergoing total correction of TOF, and preoperative sarcopenia did not predict early postoperative major adverse events.

A look into hemostatic characteristics during pediatric liver transplantation using the thromboelastometry (ROTEM® ) test.

There is a paucity of evidence about the coagulation profile regarding the complexity of children undergoing liver transplantation (LT). This study aimed to investigate intraoperative hemostatic changes during pediatric LT according to the etiology for LT and examine the ability of rotational thromboelastometry (ROTEM® , TEM International GmbH, Munich, Germany) as a point-of-care monitoring method. We evaluated 106 patients aged 3 months to 17 years undergoing LT for acute liver failure (ALF) and chronic liver disease, which consists of patients with cholestatic disease, metabolic/genetic disease, and cancer. A total of 731 ROTEM® measurements, including 301 ellagic acid to initiate clotting via the intrinsic pathway, 172 tissue factor to initiate the extrinsic clotting cascade (EXTEM), and 258 cytochalasin D to inhibit platelet activity reflecting fibrinogen (FIBTEM), were analyzed at predetermined time points (the preanhepatic, anhepatic, and postreperfusion phases). We simultaneously conducted conventional coagulation tests. In children with ALF, preanhepatic measurements of conventional coagulation tests and ROTEM® showed a more hypocoagulable state than other diseases. During LT, the coagulation profile was deranged, with a prolonged clotting time and reduced clot firmness, changes that were more profound in the cholestatic disease group. Maximum clot firmness (MCF) on EXTEM and FIBTEM were well correlated with the platelet count and fibrinogen concentration (r = 0.830, p < 0.001 and r = 0.739, p < 0.001, respectively). On the EXTEM, MCF with 30 mm predicted a platelet count <30,000/mm3 (area under the curve, 0.985), and 6 mm predicted a fibrinogen concentration <100 mg/dl on the FIBTEM (area under the curve, 0.876). However, the activated partial thromboplastin time and prothrombin time were significant but only weakly correlated with the clotting time on the ROTEM® . In children undergoing LT, coagulation profiles depend on the etiology for LT. During LT, ROTEM® parameters could help detect thrombocytopenia and hypofibrinogenemia and guide transfusion therapy as a point-of-care monitoring method.

Excess out-of-hospital cardiac arrests due to ambient temperatures in South Korea from 2008 to 2018.

Out-of-hospital cardiac arrest (OHCA) is a notable public health issue with negative outcomes, such as high mortality and aftereffects. Additionally, the adverse effects of extreme temperatures on health have become more important under climate change; however, few studies have investigated the relationship between temperature and OHCA. In this study, we examined the association between temperature and OHCA and its underlying risk factors. We conducted a two-stage time-series analysis using a Poisson regression model with a distributed lag non-linear model (DLNM) and meta-analysis, based on a nationwide dataset from South Korea (2008-2018). We found that 17.4% of excess OHCA was attributed to cold, while 0.9% was attributed to heat. Based on central estimates, excess OHCA attributed to cold were more prominent in the population with hypertension comorbidity (31.0%) than the populations with diabetes (24.3%) and heart disease (17.4%). Excess OHCA attributed to heat were larger in the populations with diabetes (2.7%) and heart disease comorbidity (2.7%) than the population with hypertension (1.2%) based on central estimates. Furthermore, the time-varying excess OHCA attributed to cold have decreased over time, and although those of heat did not show a certain pattern during the study period, there was a weak increasing tendency since 2011. In conclusion, we found that OHCAs were associated with temperature, and cold temperatures showed a greater impact than that of hot temperatures. The effects of cold and hot temperatures on OHCA were more evident in the populations with hypertension, diabetes, and heart diseases, compared to the general population. In addition, the impacts of heat on OHCA increased in recent years, while those of cold temperatures decreased. Our results provide scientific evidence for policymakers to mitigate the OHCA burden attributed to temperature.

Role of VVZ-149, a Novel Analgesic Molecule, in the Affective Component of Pain: Results from an Exploratory Proof-of-Concept Study of Postoperative Pain following Laparoscopic and Robotic-Laparoscopic Gastrectomy.

OBJECTIVE: VVZ-149 is a small molecule that both inhibits the glycine transporter type 2 and the serotonin receptor 5 hydroxytryptamine 2 A. In a randomized, parallel-group, and double-blind trial (NCT02844725), we investigated the analgesic efficacy and safety of VVZ-149 Injections, which is under clinical development as a single-use injectable product for treating moderate to severe postoperative pain. METHODS: Sixty patients undergoing laparoscopic and robotic-laparoscopic gastrectomy were randomly assigned to receive a 10-hour intravenous infusion of VVZ-149 Injections or placebo, initiated approximately 1 hour before completion of surgical suturing. Major outcomes included pain intensity and opioid consumption via patient-controlled analgesia and rescue analgesia provided "as needed." The treatment efficacy of VVZ-149 was further examined in a subpopulation requiring early rescue medication, previously associated with the presence of high levels of preoperative negative affect in a prior Phase 2 study (NCT02489526). RESULTS: Pain intensity was lower in the VVZ-149 (n = 30) than the placebo group (n = 29), reaching statistical significance at 4 hours post-emergence (P < .05), with a 29.5% reduction in opioid consumption for 24 hours and fewer demands for patient-controlled analgesia. In the rescued subgroup, VVZ-149 further reduced pain intensity (P < .05) with 32.6% less opioid consumption for 24 hours compared to placebo patients. CONCLUSIONS: VVZ-149 demonstrated effective analgesia with reduced postoperative pain and opioid requirements. Consistent with the results from the previous Phase 2 study, patients with early rescue requirement had greater benefit from VVZ-149, supporting the hypothesis that VVZ-149 may alleviate the affective component of pain and mitigate excessive use of opioids postoperatively.

Use of a High-Flow Nasal Cannula in a Child With a Functional Single Ventricle and Difficult Airway.

Inducing anesthesia and securing the airway without disrupting the patient's hemodynamic state are challenging in pediatric patients with a functional single ventricle (FSV). Here, the authors report effective use of a high-flow nasal cannula (HFNC) as a tool in providing oxygen supplementation for airway management in pediatric FSV patients with a history of a difficult airway. A female patient, aged 5 years 7 months, was admitted for extracardiac conduit Fontan procedure. The patient had a history of multiple failed attempts at endotracheal intubation and was diagnosed with retrognathia and severe oral trismus of less than 1 finger width. The patient had another event of mask ventilation failure after propofol sedation during the preoperative computed tomography scan a day before the surgery. The patient's preoperative cardiac catheterization report revealed that the Qp/Qs ratio of 0.82 at room air, and the patient's peripheral oxygen saturation (SpO2) ranged from 70% to 80% at room air. On entering the operating room, the preoxygenation process began with HFNC at an oxygen flow of 16 L/min, with a fraction of inspired oxygen (FIO2) set at 95% after light sedation with an intravenous bolus of midazolam, 0.1 mg/kg. After 4 minutes of applying HFNC, with SpO2 rising from 76% to 98%, anesthetic medications were administered intravenously without a neuromuscular blocking agent to preserve spontaneous breathing. The patient was not ventilated with a facemask but instead left with HFNC in place for continuous supplemental oxygenation. The patient's airway was secured in a single attempt in 80 seconds. HFNC is an ideal option for oxygen supplementation during airway management of pediatric FSV patients, as their balance of pulmonary and systemic flow is perturbed easily by subtle physiologic alteration and therapeutic maneuvers during the induction of general anesthesia and highly susceptible to rapid desaturation and cardiovascular collapse, and should be considered as having a physiologically difficult airway.

Clinical implication of intraoperative ventricular-arterial coupling in pediatric patients undergoing ventricular septal defects repair: A retrospective cohort study.

BACKGROUND: Ventricular-arterial coupling is the ratio of arterial elastance to ventricular end-systolic elastance. AIMS: The objective of this study was to determine the clinical implication of intraoperative ventricular-arterial coupling derived from the pressure-area relationship using transesophageal echocardiography. METHODS: This retrospective study reviewed the medical records of 72 pediatric patients with ventricular septal defects who underwent corrective surgery with cardiopulmonary bypass. The single-beat modified method was used to assess ventricular-arterial coupling. Logistic regression analyses were performed to determine the correlation between ventricular-arterial coupling and early postoperative outcomes, including the maximum vasoactive-inotropic score, length of mechanical ventilation, and length of hospital stay. RESULTS: Ventricular-arterial coupling after cardiopulmonary bypass significantly increased (from 1.0 ± 0.4 to 1.4 ± 0.8, p < .001), indicating a disproportionate increase in the arterial elastance index (from 11.5 ± 5.1 to 19.8 ± 7.5 mmHg/cm2 /m2 , p < .001) compared with the ventricular end-systolic elastance index (from 13.0 ± 6.9 to 16.9 ± 9.0 mmHg/cm2 /m2 , p < .001). Logistic regression analyses revealed that high postoperative ventricular-arterial coupling was independently associated with higher postoperative maximum vasoactive-inotropic score (>10; odds ratio [OR], 8.04; 95% confidence interval [CI], 1.38-46.85, p = .020), longer postoperative mechanical ventilation (>15 h; OR: 11.00; 95% CI: 1.26-96.45, p = .030), and longer postoperative hospital stay (>7 days; OR: 2.98; 95% CI: 1.04-8.58, p = .043). CONCLUSIONS: Ventricular-arterial coupling can be easily obtained from the intraoperative transesophageal echocardiography in pediatric patients undergoing ventricular septal defects repair. High postoperative ventricular-arterial coupling is strongly associated with worse early postoperative outcomes. Ventricular-arterial coupling shows promise as an intraoperative analysis tool that can provide insight into the impact of interventions on cardiovascular performance and identify potential targets for treatment in this population.

Respiratory Variation of Internal Carotid Artery Blood Flow Peak Velocity Measured by Transfontanelle Ultrasound to Predict Fluid Responsiveness in Infants: A Prospective Observational Study.

BACKGROUND: Cranial sonography is a widely used point-of-care modality in infants. The authors evaluated that the respiratory variation of the internal carotid artery blood flow peak velocity as measured using transfontanelle ultrasound can predict fluid responsiveness in infants. METHODS: This prospective observational study included 30 infants undergoing cardiac surgery. Following closure of the sternum, before and after the administration of 10ml · kg crystalloid, the respiratory variation of the aorta blood flow peak velocity, pulse pressure variation, and central venous pressure were obtained. The respiratory variation of the internal carotid artery blood flow peak velocity was measured using transfontanelle ultrasound. Response to fluid administration was defined as an increase in stroke volume index, as measured with transesophageal echocardiography, greater than 15% of baseline. RESULTS: Seventeen subjects (57%) were responders to volume expansion. Before fluid loading, the respiratory variation of the internal carotid artery and the aorta blood flow peak velocity (means ± SD) of the responders were 12.6 ± 3.3% and 16.0 ± 3.8%, and those of the nonresponders were 8.2 ± 3.2% and 10.9 ± 3.5%, respectively. Receiver operating characteristic curve analysis showed that the respiratory variation of the internal carotid artery and the aorta blood flow peak velocity could predict fluid responsiveness; the area under the curve was 0.828 (P < 0.0001; 95% CI, 0.647 to 0.940) and 0.86 (P = 0.0001; 95% CI, 0.684 to 0.959), respectively. The cutoff values of the respiratory variation of the internal carotid artery and the aorta blood flow peak velocity were 7.8% (sensitivity, 94%; specificity, 69%) and 13% (sensitivity, 77%; specificity, 92%), respectively. CONCLUSIONS: The respiratory variation of the internal carotid artery blood flow peak velocity as measured using transfontanelle ultrasound predicted an increase in stroke volume in response to fluid. Further research is required to establish any wider generalizability of the results.

Accuracy of pulse oximeters at low oxygen saturations in children with congenital cyanotic heart disease: An observational study.

BACKGROUND: Pulse oximetry overestimates arterial oxygen saturation (SaO2 ) at less than 90% saturation in cyanotic children. The Masimo Blue sensor (Masimo Corp., Irvine, CA) is a pulse oximetry sensor developed for use in children with cyanosis. However, there remains a lack of research in actual clinical practice. AIMS: We evaluated the intraoperative performance of three different pulse oximeters to measure oxyhemoglobin saturation (SpO2 ) at low saturations in pediatric patients with cyanotic heart disease and the influence of clinical variables (SaO2 , hemoglobin concentration, perfusion index, and weight) on the accuracy of the sensors. METHODS: This prospective observational study compared SpO2 measured using three pulse oximeters (Masimo Blue [Masimo Corp., Irvine, CA]; Masimo LNCS, and Nellcor [Medtronic, Dublin, Ireland]) at selected SaO2 ranges (≥85%, 75%-84%, 60%-74%, and < 60%). Accuracy was evaluated according to bias and Bland-Altman analysis with appropriate correction for multiple measurements. Relationships between bias and clinical variables were assessed using a generalized estimating equation. RESULTS: Two hundred and fifty-eight samples were analyzed. The mean overall bias (limits of agreement) of Masimo Blue, Masimo LNCS, and Nellcor sensor was -5.3 (-20.9 to 10.3%), -7.4 (-21.9 to 7.1%), and -7.4 (-22.5 to 15.1%), respectively. However, there was no difference in bias among the three sensors at SaO2 <60%. Generalized estimating equation showed that SaO2 value was associated with bias of all sensors. Perfusion index affected the bias of Blue sensor and LNCS sensor, and patients' weight was associated with bias of Nellcor sensor. CONCLUSION: Masimo blue sensor demonstrated overall lower bias compared to the other two sensors. However, the accuracy of all sensors was similarly poor at SaO2 less than 60%. Bias was influenced by SaO2 , perfusion index, and body weight.

Manual vs pressure-controlled facemask ventilation during the induction of general anesthesia in children: A prospective randomized controlled study.

BACKGROUND: Gastric insufflation frequently occurs during facemask ventilation in children. In the present study, we compared the incidence of gastric insufflation between pressure-controlled facemask ventilation and manual facemask ventilation during general anesthesia induction in children. METHODS: Children in the pressure-controlled ventilation group (n = 76) received pressure-controlled facemask ventilation at an inspiratory pressure of 13 cm H2 O. In the manual ventilation group (n = 75), facemask ventilation was manually performed by anesthesiologists, who tried to maintain an inspiratory pressure of 13 cm H2 O. The adjustable pressure limiting valve was set at 13 cm H2 O. The incidence of gastric insufflation during 90 seconds after the initiation of ventilation was assessed using epigastric auscultation and gastric ultrasonography. RESULTS: The incidence of gastric insufflation was significantly higher in the manual  facemask ventilation group than in the pressure-controlled ventilation group (48% vs 12%, respectively; odds ratio 7.78, 95% confidence interval [CI] 3.38-17.9; P < 0.001). The mean peak airway pressure during ventilation was significantly higher in the manual ventilation group than in the pressure-controlled ventilation group (16.1 [3.0] cm H2 O vs 13.0 [0.1] cm H2 O; 95% CI of differences, 2.36-3.71 cm H2 O; P < 0.001). The manual ventilation group exhibited a wide peak airway pressure  range (11-26 cm H2 O) and a wide variation of tidal volume (0-7.0 mL/kg) compared with those of the pressure-controlled ventilation group (13-14 cm H2 O and 0.6-16.0 mL/kg, respectively). CONCLUSION: At an inspiratory pressure of 13 cm H2 O, pressure-controlled ventilation may be more effective than manual ventilation in preventing gastric insufflation while providing stable ventilation in children.

Effect of different fraction of inspired oxygen on development of atelectasis in mechanically ventilated children: A randomized controlled trial.

BACKGROUND: The use of high fraction of inspired oxygen (FI O2 ) can cause direct pulmonary toxicity and pulmonary complications. The purpose of this study was to evaluate the effect of different FI O2 on development of intraoperative atelectasis in mechanically ventilated children using lung ultrasound. METHODS: In this randomized controlled, patient- and sonographer-blinded trial, 86 children (≤6 years) undergoing noncardiac surgery were allocated into a low (n = 43) or high (n = 43) FI O2 group. The low FI O2 group consistently received 30% air-oxygen mixture during preoxygenation, ultrasound-guided recruitment maneuver, and mechanical ventilation. The high FI O2 group received 100% oxygen during preoxygenation and ultrasound-guided recruitment maneuver and 60% air-oxygen mixture during mechanical ventilation. Positive end-expiratory pressure of 5 cm H2 O was applied in both groups. Lung ultrasound was performed one minute after the start of mechanical ventilation and at the end of surgery in both groups. Primary outcome was significant atelectasis incidence (consolidation score of ≥2 in any region) on the postoperative lung ultrasound. Secondary outcomes included significant atelectasis incidence on the preoperative lung ultrasound, incidences of intra- and postoperative desaturation, and incidences of postoperative fever and postoperative pulmonary complications. RESULTS: Significant atelectasis incidence on the postoperative lung ultrasound was similar between the low and high FI O2 groups (28% vs 37%; Pearson chi-square value = 0.847; P = .357; OR 1.531; 95% CI 0.617-3.800). Significant atelectasis incidence on the preoperative lung ultrasound was also similar between the groups (12% vs 9%; Pearson chi-square value = 0.124; P = .725; OR 0.779; 95% CI 0.194-3.125). There were no statistically significant differences in the other secondary outcomes. CONCLUSIONS: FI O2 did not affect significant atelectasis formation in mechanically ventilated children who received ultrasound-guided recruitment maneuver and positive end-expiratory pressure.

Acute Change in Ventricular Contractility-Load Coupling After Corrective Surgery for Congenital Heart Defect: A Retrospective Cohort Study.

Ventricular performance and its loading condition change drastically after surgical correction of congenital heart defect. Pressure-volume loops analysis can provide quantitative information about ventriculo-arterial coupling (VAC) indicating the interaction between ventricular contractility and loading condition. Therefore, we investigated changes in VAC after corrective surgery for ventricular septal defect (VSD)/tetralogy of Fallot (TOF), and implication of ventriculo-arterial decoupling as a prognostic factor of post-operative outcomes. In children with VSD/TOF, pre- and post-operative arterial elastance (Ea), end-systolic ventricular elastance (Ees) and VAC (Ea/Ees) were non-invasively estimated using echocardiographic parameters. Post-operative outcomes included maximum vasoactive-inotropic score, the duration of mechanical ventilation and hospital stay. Preoperatively, patients with VSD had significantly lower Ea and Ees than patients with TOF; however, VAC were preserved in both. In patients with VSD, post-operative Ea increased disproportionately to change in Ees, resulting in increased VAC. Post-operative higher VAC in patients with VSD was independently associated with maximum vasoactive-inotropic score (odds ratio [OR] 63.9; 95% Confidence Interval [CI] 4.0-553.0; P = 0.003), prolonged mechanical ventilation (OR 6.3; 95% CI 1.1-37.8; P = 0.044) and longer hospitalization (OR 17.6; 95% CI 1.6-187.0; P = 0.018). In patients with TOF, Ea and Ees reduced post-operatively; however, VAC remained unchanged and was not associated with post-operative outcomes. Despite of different loading condition, preoperative VAC maintained in both of VSD and TOF. However, particularly in VSD patients, abrupt increase in post-operative loading state induces contractility-load decoupling, which leads to worse post-operative outcomes.

Utility of Perioperative Lung Ultrasound in Pediatric Cardiac Surgery: A Randomized Controlled Trial.

BACKGROUND: Pediatric cardiac patients are at risk for perioperative respiratory insufficiency. The objective of this study was to assess the utility of perioperative lung ultrasound examination in pediatric cardiac surgery. METHODS: In this randomized, controlled trial, children (5 yr old or younger) undergoing cardiac surgery were allocated into a control (n = 61) or intervention (n = 61) group. The control group received only lung ultrasound examinations at the end of surgery and 6 to 12 h after surgery. The intervention group received lung ultrasound examinations and an ultrasound-guided recruitment maneuver depending on ultrasound findings after inducing anesthesia, at the end of surgery, and 6 to 12 h after surgery. Primary outcomes were incidences of intra- and postoperative desaturation, and postoperative pulmonary complications. Multiple comparisons were corrected (P ≤ 0.017) in the primary outcome analysis. RESULTS: Of the 120 children included in the analysis, postoperative desaturation (64% vs. 27%; P < 0.001; odds ratio [OR], 0.210; 95% CI, 0.097 to 0.456) occurred more in the control group. The incidences of intraoperative desaturation (36% vs. 19%; P = 0.033; OR, 0.406; 95% CI, 0.176 to 0.939) and postoperative pulmonary complications (12% vs. 3%; P = 0.093; OR, 0.271; 95% CI, 0.054 to 1.361) were similar between the groups. Lung ultrasound scores were better in the intervention group than in the control group. Duration of mechanical ventilation was longer in the control group than in the intervention group (38 ± 43 vs. 26 ± 25 h; 95% CI of mean difference, 0 to 25; P = 0.048). CONCLUSIONS: Perioperative lung ultrasound examination followed by ultrasound-guided recruitment maneuver helped decrease postoperative desaturation events and shorten the duration of mechanical ventilation in pediatric cardiac patients. VISUAL ABSTRACT: An online visual overview is available for this article at http://links.lww.com/ALN/B682.

Near-Infrared Spectroscopy and Vascular Occlusion Test for Predicting Clinical Outcome in Pediatric Cardiac Patients: A Prospective Observational Study.

OBJECTIVES: This study is designed to determine the feasibility and utility of vascular occlusion test variables as measured by INVOS Medtronic, Dublin, Ireland) in pediatric cardiac patients. DESIGN: A prospective observational study. SETTING: A tertiary children's hospital. PATIENTS: Children less than or equal to 8 years old who were scheduled for elective cardiac surgery under cardiopulmonary bypass. INTERVENTIONS: A vascular occlusion test (3 min of ischemia and reperfusion) was performed on the calf at three time points: after induction of anesthesia (T0), during cardiopulmonary bypass (T1), and after sternal closure (T2). MEASUREMENTS AND MAIN RESULTS: Baseline regional tissue hemoglobin oxygen saturation, deoxygenation rate, minimum regional tissue hemoglobin oxygen saturation, and reoxygenation rate were measured using INVOS. Influence of age on variables at each measurement point was also checked using linear regression analysis. Receiver operating characteristics curve analysis was performed to determine the ability of vascular occlusion test variables at T2 to predict the occurrence of major adverse events. Both the deoxygenation and reoxygenation rates were lowest in T1. There was a tendency to decreased regional tissue hemoglobin oxygen saturation in younger patients at T0 (r = 0.37; p < 0.001), T1 (r = 0.33; p < 0.001), and T2 (r = 0.42; p < 0.001) during vascular occlusion. Minimum regional tissue hemoglobin oxygen saturation was correlated with age at T0 (r = 0.51; p < 0.001) and T2 (r = 0.35; p = 0.001). Patients with major adverse events had similar baseline regional tissue hemoglobin oxygen saturation but lower minimum regional tissue hemoglobin oxygen saturation (48.8% ± 19.3% vs 63.3% ± 13.9%; p < 0.001) and higher reoxygenation rate (4.30 ± 3.20 vs 2.57 ± 2.39 %/s; p = 0.008) at T2 compared with those without. The minimum regional tissue hemoglobin oxygen saturation less than 51% after sternal closure could predict the occurrence of major adverse events with a sensitivity of 61.1% and a specificity of 85.4%. CONCLUSIONS: Vascular occlusion test using INVOS can be applied in children undergoing cardiac surgery. Vascular occlusion test variables are influenced by age and cardiopulmonary bypass. The minimum regional tissue hemoglobin oxygen saturation less than 51% after sternal closure is associated with worse clinical outcomes in pediatric cardiac patients.

Risk factors of acute kidney injury in children after cardiac surgery.

BACKGROUND: The objective of this retrospective study was to determine the risk factors for acute kidney injury (AKI), including albumin, in children who underwent cardiac surgery. In addition, we evaluated the association between preoperative serum albumin level and postoperative AKI in these patients. METHODS: This retrospective study included 505 pediatric patients who underwent congenital cardiac surgery. Preoperative and perioperative risk factors for AKI, including serum albumin level, were assessed. AKI incidence within 7 postoperative days was determined using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Multivariable logistic regression analysis was performed to evaluate the association between possible risk factors and postoperative AKI. RESULTS: Of 505 pediatric patients, 185 (36.6%) developed postoperative AKI. The preoperative serum albumin level was associated with postoperative AKI (odds ratio [OR] 0.506, 95% confidence interval [CI] 0.325-0.788; P = 0.003). Other independent factors associated with AKI were age <12 months (OR 1.911, 95% CI 1.166-3.132; P = 0.007), preoperative pulmonary hypertension (OR 1.853, 95% CI 1.182-2.907; P = 0.01), and cardiopulmonary bypass (CPB) duration (OR 1.006, 95% CI 1.003-1.009; P = 0.002). Patients with AKI had higher incidence of postoperative complications, longer mechanical ventilation times, and more prolonged intensive care unit and hospital stays than patients without AKI. CONCLUSIONS: Preoperative serum albumin level, age <12 months, preoperative pulmonary hypertension, and CPB duration were associated with risk for postoperative AKI in children who underwent congenital cardiac surgery.

Optimal inspiratory pressure for face mask ventilation in paralyzed and unparalyzed children to prevent gastric insufflation: a prospective, randomized, non-blinded study.

BACKGROUND: Gastric insufflation is common during face mask ventilation and results in unfavourable respiratory events in children. The purpose of this study was to evaluate the effect of a muscle relaxant on gastric insufflation and determine the optimal inspiratory pressure during face mask ventilation in children. METHODS: Children aged one month to five years were randomly assigned to neuromuscular blocker (NM) or non-neuromuscular blocker (non-NM) groups. After administering intravenous anesthetics, face mask ventilation commenced via pressure-controlled mechanical ventilator. Initial inspiratory pressure was 10 cmH2O and was increased by 2 cmH2O until gastric insufflation was detected via gastric ultrasonography or epigastric auscultation. The primary outcome was the difference in the inspiratory pressure that causes gastric insufflation between the two groups. Diagnostic methods that detect gastric insufflation first were also evaluated. RESULTS: There was no significant difference in the median [interquartile range] inspiratory pressure inducing gastric insufflation between the non-NM (n = 52) and NM groups (n = 60) (18 [16-18] cmH2O vs 18.0 [16-20] cmH2O; median difference, 0 cmH2O; 95% confidence interval [CI], 0 to 2; P = 0.57). The incidence of gastric insufflation increased with increasing inspiratory pressure. Gastric insufflation was detected first by ultrasonography in 44% and by epigastric auscultation in 19% of the non-NM group (difference in percentage, 25%; 95% CI, 6 to 42; P = 0.006) and by ultrasonography in 73% and by epigastric auscultation in 7% of the NM group (difference in percentage, 66%; 95% CI, 50 to 78; P < 0.001). CONCLUSIONS: A neuromuscular blocking agent has minimal effect on the inspiratory pressure that causes gastric insufflation during face mask ventilation in children. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02471521); registered 15 June 2015.

Potential Role of Transfontanelle Ultrasound for Infants Undergoing Modified Blalock-Taussig Shunt.

OBJECTIVE: Transfontanelle ultrasound is a noninvasive method for assessing cerebral blood flow in neonates and infants. The authors applied this technique as a point-of-care tool, before and after modified Blalock-Taussig shunt procedure, to evaluate cerebral perfusion. DESIGN: Retrospective, observational study. SETTING: Tertiary care children's hospital. PARTICIPANTS: Ten infants undergoing modified Blalock-Taussig shunt procedure. OBSERVATION: Transfontanelle ultrasound examinations with modified resistive index were analyzed before and after the modified Blalock-Taussig shunt procedure. MEASUREMENTS AND MAIN RESULTS: Two infants died and 2 patients required a revision procedure due to shunt thrombosis. Baseline-modified resistive index and regional cerebral oxygenation were comparable between the right and left hemisphere. However, after the procedure, the modified resistive index decreased at both sides of the internal carotid arteries compared with baseline values (p value right side = 0.012, left side = 0.036) and was greater at the ipsilateral internal carotid arteries with the shunt (p = 0.012, mean difference = 0.07, 95% confidence interval [CI] 0.02-0.12). Four infants with the large patent ductus arteriosus presented diastolic reverse flows at both internal carotid arteries at baseline. However, the diastolic reverse flow disappeared after the procedure. An infant who developed diastolic reverse flow after the procedure, died. CONCLUSIONS: Transfontanelle ultrasound is a feasible tool for assessing the pattern of shunt flow and cerebral perfusion before and after the modified Blalock-Taussig shunt procedure. The transfontanelle ultrasound examinations may have potential role in assessing "over-shunting," but it needs more studies.

Risk Factors for Intraoperative Hypocapnia in Pediatric Neurosurgical Patients: A Retrospective Cohort Study.

BACKGROUND: Hypocapnia has been associated with an increased risk and adverse outcomes in the injured brain. This study aimed to identify risk factors of intraoperative hypocapnia in pediatric neurosurgical patients when tidal volumes and respiratory rates were determined based on their weight and age, respectively. METHODS: Electronic medical records of pediatric patients (≤18 years) who underwent neurosurgery from December 2014 to January 2016 were retrospectively reviewed. Minute ventilation was fixed according to each patient's weight and age. Hypocapnia was defined as arterial partial pressure of carbon dioxide <35 mm Hg from intraoperative arterial blood gas analysis. Patients were divided into hypocapnia and nonhypocapnia groups. Risk factors for intraoperative hypocapnia were found using univariable and multivariable logistic regression analyses. RESULTS: Of the 333 pediatric patients analyzed, 101 (30%) and 232 (70%) were included in the hypocapnia and nonhypocapnia groups, respectively. There was no difference in the minute ventilation between the two groups. The hypocapnia group had more patients taking valproate (8.9 vs. 2.2%; p = 0.008; OR, 4.441; 95% CI, 1.449-13.61) and carbonic anhydrase inhibitors (7.9 vs. 2.2%; p = 0.018; OR, 3.905; 95% CI, 1.245-12.25). An operation for hydrocephalus was more commonly performed in the hypocapnia group (26.7 vs. 15.9%; p = 0.017; OR, 1.923; 95% CI, 1.094-3.379). In the multivariable regression analysis, valproate (OR, 3.939; 95% CI, 1.250-12.41; p = 0.019), carbonic anhydrase inhibitor (OR, 3.345; 95% CI, 1.029-10.88; p = 0.045), and operation for hydrocephalus (OR, 1.838; 95% CI, 1.032-3.272; p = 0.039) were independent risk factors for intraoperative hypocapnia. CONCLUSIONS: Pediatric patients taking valproate and carbonic anhydrase inhibitors and who were scheduled for surgery of hydrocephalus were at risk of developing intraoperative hypocapnia during neurosurgery, a finding warning the surgeon that a conventional ventilatory strategy would endanger these patients.

An observational study of the optimal placement of a cerebral oximeter probe to avoid the frontal sinus in children.

The frontal sinus is an airspace behind the brow ridge in the skull and can affect the accuracy of the regional cerebral oxygen saturation measurements. We evaluated the optimal location for placement of a cerebral oximeter probe while avoiding the frontal sinus in pediatric patients. This retrospective observational study included 203 pediatric patients aged 3-17 years who had undergone brain computed tomography from November 2010 to December 2015. The patients were divided into five subgroups based on their age. The frontal sinus height was measured from the superior orbital rim. Pneumatization of the frontal sinus was not visible in 78% (3-5 years) and 22% (6-8 years) of the patients. The mean (SD) of the frontal sinus height was 5.9 (3.4), 9.5 (4.1), 14.0 (6.2) 18.6 (8.4), and 21.1 (7.9) mm in the 3-5, 6-8, 9-11, 12-14, and 15-17 year age-groups, respectively. Age was positively correlated with the frontal sinus height (r = 0.61, P < 0.001, 95% confidence interval [CI] 0.513-0.688). A frontal sinus height shorter than 1, 2, and 3 cm were seen in 10 of 11 (91%), 69 of 74 (94%), and 108 of 118 (90%) patients aged 3-5, 6-10, and 11-17 years, respectively. When oximeter probes are applied in pediatric patients, placement based on age can help avoid the frontal sinus.

The Efficacy of Intraoperative EEG to Predict the Occurrence of Emergence Agitation in the Postanesthetic Room After Sevoflurane Anesthesia in Children.

PURPOSE: Emergence agitation (EA) is common after sevoflurane anesthesia, but there are no definite predictors. This study investigated whether intraoperative electroencephalography (EEG) can indicate the occurrence of EA in children. DESIGN: A prospective predictive study design was used. METHODS: EEG-derived parameters (spectral edge frequency 95, beta, alpha, theta, and delta power) were measured at 1.0 minimum alveolar concentration (MAC) and 0.3 MAC of end-tidal sevoflurane (EtSEVO) in 29 patients. EA was evaluated using an EA score (EAS) in the postanesthetic care unit on arrival (EAS 0) and at 15 and 30 minutes after arrival (EAS 15 and EAS 30). The correlation between EEG-derived parameters and EAS was analyzed using Spearman correlation, and receiver-operating characteristic curve analysis was used to measure the predictability. FINDINGS: EA occurred in 11 patients. The alpha power at 1.0 MAC of EtSEVO was correlated with EAS 15 and EAS 30. The theta/alpha ratio at 0.3 MAC of EtSEVO was correlated with EAS 30. The area under the receiver-operating characteristic curve of percentage of alpha bands at 0.3 MAC of EtSEVO and the occurrence of EA was 0.672. CONCLUSIONS: Children showing high-alpha powers and low theta powers (= low theta/alpha ratio) during emergence from sevoflurane anesthesia are at high risk of EA in the postanesthetic care unit.