Prospective comparative analysis of noninvasive body temperature monitoring using zero heat flux technology (SpotOn sensor) compared with esophageal temperature monitoring during pediatric surgery.

Maintaining body temperature in pediatric patients is critical, but it is often difficult to use currently accepted core temperature measurement methods. Several studies have validated the use of the SpotOn sensor for measuring core temperature in adults, but studies on pediatric patients are still lacking. The aim of this study was to investigate the accuracy of the SpotOn sensor compared with that of esophageal temperature measurement in pediatric patients intraoperatively. Children aged 1-8 years with American Society of Anesthesiology Physical Condition Classification I or II scheduled to undergo elective ear surgery for at least 30 min under general anesthesia were enrolled. Body core temperature was measured every 15 min after induction till the end of anesthesia with an esophageal probe, axillary probe, and SpotOn sensor. We included 49 patients, providing a total 466 paired measurements. Analysis of Pearson rank correlation between SpotOn and esophageal pairs showed a correlation coefficient (r) of 0.93 (95% confidence interval [CI] 0.92-0.94). Analysis of Pearson rank correlation between esophageal and axillary pairs gave a correlation coefficient (r) of 0.89 (95% CI 0.87-0.91). Between the SpotOn and esophageal groups, Bland-Altman analysis revealed a bias (SD, 95% limits of agreement) of -0.07 (0.17 [-0.41-0.28]). Between the esophageal and axillary groups, Bland-Altman analysis showed a bias (SD, 95% limits of agreement) of 0.45 (0.22 [0-0.89]). In pediatric patients during surgery, the SpotOn sensor showed high correlation and agreement with the esophageal probe, which is a representative core temperature measurement method.

Serious acid-base disorder or life-threatening arrhythmia in patients with ABO-incompatible liver transplantation who received therapeutic plasma exchange - A report of two cases.

BACKGROUND: Excessive citrate load during therapeutic plasma exchange (TPE) can cause metabolic alkalosis with compensatory hypercarbia and electrolyte disturbances. If TPE is required immediately before ABO-incompatible (ABOi) liver transplant (LT) surgery, metabolic derangement and severe electrolyte disturbance could worsen during LT anesthesia. CASE: We report two ABOi LT cases who received TPE on the day of surgery because isoagglutinin titers did not be dropped below 1:8. One case had a surprisingly high metabolic alkalosis with a pH of 7.73 immediately after tracheal intubation because of hyperventilation during mask bagging. The other experienced sudden ventricular tachycardia and blood pressure drop after surgical incision accompanied with severe hypokalemia of 1.8 mmol/L despite supplementation with potassium. CONCLUSIONS: Special attention should be paid to patients who just completed TPE the operative day morning as they are vulnerable to severe acid-base disturbances and life-threatening ventricular arrhythmias in ABOi LT.

Intraoperative lactic acid concentration during liver transplantation and cutoff values to predict early mortality: a retrospective analysis of 3,338 cases.

BACKGROUND: We aimed to explore the distribution of intraoperative lactic acid (LA) level during liver transplantation (LT) and determine the optimal cutoff values to predict post-LT 30-day and 90-day mortality. METHODS: Intraoperative LA data from 3,338 patients were collected between 2008 to 2019 and all-cause mortalities within 30 and 90 days were retrospectively reviewed. Of the three LA levels measured during preanhepatic, anhepatic, and neohepatic phase of LT, the peak LA level was selected to explore the distribution and predict early post-LT mortality. To determine the best cutoff values of LA, we used a classification and regression tree algorithm and maximally selected rank statistics with the smallest P value. RESULTS: The median intraoperative LA level was 4.4 mmol/L (range: 0.5-34.7, interquartile range: 3.0-6.2 mmol/L). Of the 3,338 patients, 1,884 (56.4%) had LA levels > 4.0 mmol/L and 188 (5.6%) had LA levels > 10 mmol/L. Patients with LA levels > 16.7 mmol/L and 13.5-16.7 mmol/L showed significantly higher 30-day mortality rates of 58.3% and 21.2%, respectively. For the prediction of the 90-day mortality, 8.4 mmol/L of intraoperative LA was the best cutoff value. CONCLUSIONS: Approximately 6% of the LT recipients showed intraoperative hyperlactatemia of > 10 mmol/L during LT, and those with LA > 8.4 mmol/L were associated with significantly higher early post-LT mortality.

Preoperative hyperlactatemia and early mortality after liver transplantation: selection of important variables using random forest survival analysis.

BACKGROUND: Generally, lactate levels > 2 mmol/L represent hyperlactatemia, whereas lactic acidosis is often defined as lactate > 4 mmol/L. Although hyperlactatemia is common finding in liver transplant (LT) candidates, association between lactate and organ failures with Acute-on-chronic Liver Failure (ACLF) is poorly studied. We searched the important variables for pre-LT hyperlactatemia and examined the impact of preoperative hyperlactatemia on early mortality after LT. METHODS: A total of 2,002 patients from LT registry between January 2008 and February 2019 were analyzed. Six organ failures (liver, kidney, brain, coagulation, circulation, and lung) were defined by criteria of EASL-CLIF ACLF Consortium. Variable importance of preoperative hyperlactatemia was examined by machine learning using random survival forest (RSF). Kaplan-Meier Survival curve analysis was performed to assess 90-day mortality. RESULTS: Median lactate level was 1.9 mmol/L (interquartile range: 1.4, 2.4 mmol/L) and 107 (5.3%) patients showed > 4.0 mmol/L. RSF analysis revealed that the four most important variables for hyperlactatemia were MELD score, circulatory failure, hemoglobin, and respiratory failure. The 30-day and 90-day mortality rates were 2.7% and 5.1%, whereas patients with lactate > 4.0 mmol/L showed increased rate of 15.0% and 19.6%, respectively. CONCLUSIONS: About 50% and 5% of LT candidates showed pre-LT hyperlactatemia of > 2.0 mmol/L and > 4.0 mmol/L, respectively. Pre-LT lactate > 4.0 mmol/L was associated with increased early post-LT mortality. Our results suggest that future study of correcting modifiable risk factors may play a role in preventing hyperlactatemia and lowering early mortality after LT.

Markedly prolonged QTc interval in end-stage liver disease and risk of 30-day cardiovascular event after liver transplant.

BACKGROUND AND AIM: The proportional increase of corrected QT interval (QTc) along end-stage liver disease (ESLD) severity may lead to inconsistent outcome reporting if based on conventional threshold of prolonged QTc. We investigated the comprehensive QTc distribution among ESLD patients and assessed the association between QTc > 500 ms, a criterion for diagnosing severe long-QT syndrome, and the 30-day major adverse cardiovascular event (MACE) after liver transplantation (LT) and identified the risk factors for developing QTc > 500 ms. METHODS: Data were collected prospectively from the Asan LT Registry between 2011 and 2018, and outcomes were retrospectively reviewed. Multivariable analysis and propensity score-weighted adjusted odds ratios (ORs) were calculated. Thirty-day MACEs were defined as the composite of cardiovascular mortality, arrhythmias, myocardial infarction, pulmonary thromboembolism, and/or stroke. RESULTS: Of 2579 patients, 194 (7.5%) had QTc > 500 ms (QTc500_Group), and 1105 (42.8%) had prolonged QTc (QTcP_Group), defined as QTc > 470 ms for women and >450 ms for men. The 30-day MACE occurred in 336 (13%) patients. QTc500_Group showed higher 30-day MACE than did those without (20.1% vs 12.5%, P = 0.003), with corresponding adjusted OR of 1.24 (95% CI: 1.06-1.46, P = 0.007). However, QTcP_Group showed comparable 30-day MACE (13.3% vs 12.8% without prolonged QTc, P = 0.764). Significant risk factors for QTc > 500 ms development were advanced liver disease, female sex, hypokalemia, hypocalcemia, high left ventricular end-diastolic volume, and tachycardia. CONCLUSION: Our results revealed that, among ESLD patients, a novel threshold of QTc > 500 ms was associated with post-LT 30-day MACE but not with conventional threshold, indicating that a longer QTc threshold should be considered for this unique patient population.

Prediction of all-cause mortality after liver transplantation using left ventricular systolic and diastolic function assessment.

Although pretransplant cardiac dysfunction is considered a major predictor of poor outcomes after liver transplantation (LT), the ability of left ventricular (LV) systolic/diastolic function (LVSF/LVDF), together or individually, to predict mortality after LT is poorly characterized. We retrospectively evaluated pretransplant clinical and Doppler echocardiographic data of 839 consecutive LT recipients from 2009 to 2012 aged 18-60 years. The primary endpoint was all-cause mortality at 4 years. The overall survival rate was 91.2%. In multivariate Cox analysis, reduced LV ejection fraction (LVEF, P = 0.014) and decreased transmitral E/A ratio(P = 0.022) remained significant prognosticators. In LVSF analysis, patients with LVEF≤60% (quartile [Q]1) had higher mortality than those with LVEF>60% (hazard ratio = 1.90, 95% confidence interval = 1.15-3.15, P = 0.012). In LVDF analysis, patients with an E/A ratio<0.9(Q1) had a 2.19-fold higher risk of death (95% confidence interval = 1.11-4.32, P = 0.024) than those with an E/A ratio>1.4(Q4). In combined LVDF and LVSF analysis, patients with an E/A ratio<0.9 and LVEF≤60% had poorer survival outcomes than patients with an E/A ratio≥0.9 and LVEF>60% (79.5% versus 93.3%, P = 0.001). Patients with an early mitral inflow velocity/annular velocity (E/e' ratio)>11.5(Q4) and LV stroke volume index (LVSVI)<33mL/m2(Q1) showed worse survival than those with an E/e' ratio≤11.5 and LVSVI ≥33mL/m2(78.4% versus 92.2%, P = 0.003). A combination of LVSF and LVDF is a better predictor of survival than LVSF or LVDF alone.

Dural sac area is a more sensitive parameter for evaluating lumbar spinal stenosis than spinal canal area: A retrospective study.

Narrowing of the dural sac cross-sectional area (DSCSA) and spinal canal cross-sectional area (SCCSA) have been considered major causes of lumbar central canal spinal stenosis (LCCSS). DSCSA and SCCSA were previously correlated with subjective walking distance before claudication occurs, aging, and disc degeneration. DSCSA and SCCSA have been ideal morphological parameters for evaluating LCCSS. However, the comparative value of these parameters is unknown and no studies have evaluated the clinical optimal cut-off values of DSCSA and SCCSA. This study assessed which parameter is more sensitive.Both DSCSA and SCCSA samples were collected from 135 patients with LCCSS, and from 130 control subjects who underwent lumbar magnetic resonance imaging (MRI) as part of a medical examination. Axial T2-weighted MRI scans were acquired at the level of facet joint from each subject. DSCSA and SCCSA were measured at the L4-L5 intervertebral level on MRI using a picture archiving and communications system.The average DSCSA value was 151.67 ±â€Š53.59 mm in the control group and 80.04 ±â€Š35.36 mm in the LCCSS group. The corresponding average SCCSA values were 199.95 ±â€Š60.96 and 119.17 ±â€Š49.41 mm. LCCSS patients had significantly lower DSCSA and SCCSA (both P < .001). Regarding the validity of both DSCSA and SCCSA as predictors of LCCSS, Receiver operating characteristic curve analysis revealed an optimal cut-off value for DSCSA of 111.09 mm, with 80.0% sensitivity, 80.8% specificity, and an area under the curve (AUC) of 0.87 (95% confidence interval, 0.83-0.92). The best cut off-point of SCCSA was 147.12 mm, with 74.8% sensitivity, 78.5% specificity, and AUC of 0.85 (95% confidence interval, 0.81-0.89).DSCSA and SCCSA were both significantly associated with LCCSS, with DSCSA being a more sensitive measurement parameter. Thus, to evaluate LCCSS patients, pain specialists should more carefully investigate the DSCSA than SCCSA.

Thalamic Pain Misdiagnosed as Cervical Disc Herniation.

Thalamic pain is a primary cause of central post-stroke pain (CPSP). Clinical symptoms vary depending on the location of the infarction and frequently accompany several pain symptoms. Therefore, correct diagnosis and proper examination are not easy. We report a case of CPSP due to a left acute thalamic infarction with central disc protrusion at C5-6. A 45-year-old-male patient experiencing a tingling sensation in his right arm was referred to our pain clinic under the diagnosis of cervical disc herniation. This patient also complained of right cramp-like abdominal pain. After further evaluations, he was diagnosed with an acute thalamic infarction. Therefore detailed history taking should be performed and examiners should always be aware of other symptoms that could suggest a more dangerous disease.

Arrhythmogenic potential develops rapidly at graft reperfusion before the start of hypotension during living-donor liver transplantation.

BACKGROUND: Detailed profiles of acute hypothermia and electrocardiographic (ECG) manifestations of arrhythmogenicity were examined to analyze acute hypothermia and ventricular arrhythmogenic potential immediately after portal vein unclamping (PVU) in living-donor liver transplantation (LT). METHODS: We retrospectively analyzed electronically archived medical records (n = 148) of beat-to-beat ECG, arterial pressure waveforms, and blood temperature (BT) from Swan-Ganz catheters in patients undergoing living-donor LT. The ECG data analyzed were selected from the start of BT drop to the initiation of systolic hypotension after PVU. RESULTS: On reperfusion, acute hypothermia of < 34℃, < 33℃ and < 32℃ developed in 75.0%, 37.2% and 11.5% of patients, respectively. BT decreased from 35.0℃ ± 0.8℃ to 33.3℃ ± 1.0℃ (range 35.8℃-30.5℃). The median time to nadir of BT was 10 s after PVU. Difference in BT (ΔBT) was weakly correlated with graft-recipient weight ratio (GRWR; r = 0.22, P = 0.008). Compared to baseline, arrhythmogenicity indices such as corrected QT (QTc), Tp-e (T wave peak to end) interval, and Tp-e/QTc ratio were prolonged (P < 0.001 each). ST height decreased and T amplitude increased (P < 0.001 each). However, no correlation was found between ΔBT and arrhythmogenic indices. CONCLUSIONS: In living-donor LT, regardless of extent of BT drop, ventricular arrhythmogenic potential developed immediately after PVU prior to occurrence of systolic hypotension.

High Left Ventricular Filling Pressure on Doppler Echocardiography Is Associated With Graft Failure and Overall Mortality Following Kidney Transplantation.

OBJECTIVE: Although E/e´ is prognostic of mortality in patients with end-stage renal disease (ESED), little is known about the prognostic implications of E/e´ following kidney transplant (KT). The objective of this study was to evaluate whether an elevated E/e´ is associated with graft function, postoperative hemodialysis, and overall mortality in end-stage renal disease patients following KT. DESIGN: A retrospective observational study. SETTING: Tertiary teaching hospital. PARTICIPANTS: In total, 1,045 patients underwent KT at the authors' hospital between January 2006 and December 2013. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Patients were divided into groups with an E/e´<15 or≥15, as assessed by preoperative echocardiography (median time from preoperative assessment of echocardiography to surgery: 37 days [IQR: 16-68 days]). Of 1,045 patients, 821 patients (78.6%) had an E/e´<15, and 224 patients (21.4%) had an E/e´≥15. Multivariate analysis indicated that age (odds ratio [OR]: 1.03; 95% confidence interval [CI]: 1.01-1.04, p = 0.001), diabetes mellitus (OR: 2.7; CI: 1.94-3.83, p<0.001), ß-blocker (OR: 1.4; CI: 1.03-1.95, p = 0.034), left atrial dimension (OR: 1.07; CI: 1.04-1.11, p<0.001), and left ventricular mass index (OR: 1.02; CI: 1.01-1.03, p<0.001) are predictive of E/e´≥15. After adjustment using inverse probability of treatment weighting, E/e´≥15 also was associated independently with postoperative hemodialysis (OR: 2.0; 95% CI: 1.5-2.6, p<0.001), graft failure (OR: 1.7; 95% CI: 1.4-2.2; p<0.001), and overall mortality (hazard ratio [HR]: 3.2; 95% CI: 2.1-4.8, p<0.001). CONCLUSIONS: Preoperative E/e´ is a prognostic indicator of overall mortality in ESRD patients undergoing KT.

Hypoalbuminemia Within Two Postoperative Days Is an Independent Risk Factor for Acute Kidney Injury Following Living Donor Liver Transplantation: A Propensity Score Analysis of 998 Consecutive Patients.

OBJECTIVE: Acute kidney injury is a known major complication of liver transplantation. Previous reports have shown that hypoalbuminemia is associated with an increased risk of acute kidney injury. However, little is known about the relationship between the early postoperative albumin level and acute kidney injury after living donor liver transplantation. The aim of this study was to identify the influence of the postoperative albumin level on acute kidney injury prevalence after living donor liver transplantation. DESIGN: A retrospective analysis. SETTING: A tertiary care university hospital. PATIENTS: Nine hundred and ninety-eighty patients underwent living donor liver transplantation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We divided the enrolled patients into two groups: group 1 included patients whose postoperative albumin level was less than 3.0 g/dL (n = 522), and group 2 included patients with an albumin level greater than or equal to 3.0 g/dL (n = 476). The prevalence of acute kidney injury, major adverse cardiac events, hospital stay, ICU stay, 30-day mortality, and overall mortality was analyzed using inverse probability of treatment weighting and propensity-score matching (n = 249 pairs) analysis. The prevalence of acute kidney injury was higher in group 1 defined by both Acute Kidney Injury Network (after adjusting for inverse probability of treatment weighting [n = 364; 69.7%] and propensity-score matching [n = 152; 61.0%]) and Risk, Injury, Failure, Loss, and End-stage kidney disease criteria (after adjusting for inverse probability of treatment weighting [n = 419; 80.3%] and propensity-score matching [n = 190; 76.3%]). The overall mortality was higher in group 1 after adjusting for inverse probability of treatment weighting (n = 61; 11.7%) and propensity-score matching (n = 23; 9.2%). The hospital (p < 0.001) and ICU (p = 0.006) stays were significantly prolonged in group 1. Acute kidney injury was associated with ICU stay by the Acute Kidney Injury Network criteria (p = 0.034), and overall mortality was correlated with acute kidney injury by the Risk, Injury, Failure, Loss, and End-stage kidney disease criteria (p = 0.014). CONCLUSIONS: Early postoperative hypoalbuminemia is an independent risk factor for acute kidney injury, and postoperative acute kidney injury is related to postoperative ICU stay and overall mortality after living donor liver transplantation.

Measurement of respiratory pulse transit time variation as an intravascular volume index in simulated hemorrhage.

BACKGROUND: We examined the usefulness of respiratory pulse transit time (PTT) variation as an intravascular volume index in young, healthy, spontaneous, paced breathing volunteers exposed to simulated central hypovolemia by lower body negative pressure (LBNP). METHODS: With paced breathing at 0.25 Hz, beat-to-beat finger blood pressure (BP), heart rate (HR), cardiac output (CO), stroke volume (SV), total peripheral resistance (TPR), and PTT were measured non-invasively in 18 healthy volunteers. Graded central hypovolemia was generated using LBNP from 0 to -20, -30, -40, and -50 mmHg. Respiratory PTT variation (PTTV) was calculated as the difference of maximal and minimal values divided by their respective means. Respiratory-frequency PTT variability (PTTRF) using power spectral analysis was also estimated. RESULTS: During LBNP, SV, CO and PTTRF decreased, but PTT, PTTV and TPR increased significantly. PTTV did not correlate with SV changes (r = -0.08, P = 0.52), but PTTRF (r = 0.58, P < 0.01) and PTT (r = 0.43, P < 0.01) did during progressive hypovolemia. CONCLUSIONS: PTTRF is more applicable to the changes in intravascular volume than PTT and PTTV, suggesting spectral analysis of PTT might be used as a dynamic preload index in patients with spontaneous and paced breathing condition, which needs further studies.