Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Opt Express ; 27(12): A738-A745, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-31252850

ABSTRACT

The performance of AlGaN-based mid and deep ultraviolet light emitting diodes (LEDs) is severely limited by electron overflow and by the poor hole injection into the device active region. We have studied the effect of various electron blocking layers on the performance of AlGaN LEDs operating at ~280 nm. It is observed that, compared to conventional p-type electron blocking layer, the incorporation of an n-type AlN/AlGaN superlattice electron blocking layer before the active region can significantly improve the device performance by reducing electron overflow without compromising hole injection. Direct on-wafer measurement showed an external quantum efficiency ~4.4% and wall-plug efficiency ~2.8% by optimizing the design of n-type AlN/AlGaN superlattice electron blocking layer, which is nearly a factor of five to ten times better than identical devices but with the incorporation of a conventional p-type electron blocking layer.

2.
Transplant Proc ; 49(5): 1092-1096, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28583534

ABSTRACT

BACKGROUND: The importance of heart rate (HR) measurement as a prognostic factor has been recognized in many clinical conditions, such as hypertension, coronary artery disease, or heart failure. Patients with liver cirrhosis tend to have increased resting HR as consequence of hyperdynamic circulation. In the current study, we examined whether pretransplant resting increased HR is associated with overall mortality in cirrhotic patients following liver transplantation (LT). PATIENTS AND METHODS: We retrospectively collected and analyzed the data of 881 liver recipients who underwent LT surgery between October 2009 and September 2012. Patients were categorized into 3 groups by tertile of resting HR as follows: tertile 1 group, HR ≤ 65 beats per minute (bpm); tertile 2 group, HR 66 to 80 bpm; and tertile 3 group, HR > 80 bpm. RESULTS: Kaplan-Meier analysis showed that the all-cause mortality rate was significantly different according to tertiles of HR (P = .016, log-rank test). The multivariate Cox regression analysis showed that tertile 3 group was significantly associated with higher risk for all-cause mortality (hazard ratio 1.83, 95% confidence interval, 1.10-3.07; P = .021) compared with tertile 1 group, after adjusting for clinically significant variables in univariate analysis. CONCLUSIONS: Our results demonstrate that pretransplant resting tachycardia can identify patients at high risk of death in cirrhotic patients following LT, suggesting that further study will be need to clarify relationship between HR burden and sympathetic cardiac neuropathy.


Subject(s)
Heart Rate , Liver Transplantation/mortality , Aged , Female , Humans , Kaplan-Meier Estimate , Liver Cirrhosis/surgery , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors
3.
Transplant Proc ; 48(10): 3328-3335, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27931578

ABSTRACT

BACKGROUND: Although left ventricular diastolic dysfunction (LVDD) is a pronounced feature of adult cirrhotic cardiomyopathy and a major predictor of poor outcomes following liver transplantation (LT), little is known about if pretransplant cardiac dysfunction affects perioperative outcomes in pediatric LT. METHODS: We retrospectively evaluated pretransplant clinical and Doppler echocardiographic data for 45 consecutive pediatric LT recipients who were treated between 2007 and 2013 (median age = 15 months; interquartile range = 9 to 78 months). LVDD was defined according to the cirrhotic cardiomyopathy criteria, and the myocardial performance index (MPI) was measured using tissue Doppler imaging. Intraoperative data and hospitalization days following LT were compared. RESULTS: LVDD and MPI ≥0.5 (defined as a z score ≥2) were observed in 13% and 27% of patients, respectively. Patients with an MPI ≥0.5 demonstrated the increased accumulation of lactate at the end of their LT operation (mean = 2.48 vs 0.82; P = .026) compared with patients with an MPI <0.5. The hospital stay was longer in patients with LVDD (median = 46 days vs 30 days; P = .041) and patients with an MPI ≥0.5 (median = 38 days vs 29 days; P = .014) compared with patients without LVDD and MPI <0.5, respectively. CONCLUSIONS: LVDD might be less prevalent (13%) in pediatric patients compared with adults. However, pretransplant cardiac dysfunction in patients with LVDD and an MPI ≥0.5 adversely affects perioperative outcomes, necessitating that such pediatric LT recipients be cautiously observed perioperatively.


Subject(s)
Liver Transplantation/adverse effects , Postoperative Complications/etiology , Ventricular Dysfunction, Left/complications , Child , Child, Preschool , Echocardiography, Doppler , Female , Humans , Infant , Length of Stay , Male , Postoperative Complications/epidemiology , Preoperative Period , Prevalence , Retrospective Studies , Severity of Illness Index , Ventricular Dysfunction, Left/physiopathology
4.
Transplant Proc ; 45(6): 2272-6, 2013.
Article in English | MEDLINE | ID: mdl-23871183

ABSTRACT

BACKGROUND: Cerebral blood flow and intracranial pressure (ICP) has been known to be increased after graft reperfusion during liver transplantation, which was correlated with arterial carbon dioxide concentration (PaCO2). Ultrasonographic measurement of optic nerve sheath diameter (ONSD) is a simple and noninvasive method for evaluating ICP. We investigated the correlation between ONSD and the PaCO2 during reperfusion in liver transplant recipients. METHODS: Twenty liver transplant recipients with end-stage liver disease were enrolled. We measured ONSD and PaCO2 at 6 time points: preinduction, preanhepatic phase, anhepatic phase, 5 minutes after reperfusion, 30 minutes after reperfusion, and neohepatic phase. Pearson correlation analysis and receiver operating characteristics (ROC) curve analysis were performed. RESULTS: ONSD measured 5 minutes after reperfusion was significantly higher compared with the other time points. Differences in ONSD between the anhepatic phase and 5 minutes after reperfusion demonstrated significant correlations with both PaCO2 at the anhepatic phase and 5 minutes after reperfusion (both P < .001). On the ROC curve analysis, PaCO2 of 35 mm Hg at the anhepatic phase could be used to indicate ≥20% changes in ONSD after reperfusion. There were significant increases in ONSD after graft reperfusion in liver transplant recipients with PaCO2 ≥ 35 mm Hg at the anhepatic phase (P = .004). CONCLUSION: ONSD was increased just after reperfusion, which demonstrated good correlation with PaCO2 during reperfusion in liver transplant recipients. This finding suggests that the carbon dioxide can play a key role in increasing ONSD during hepatic graft reperfusion.


Subject(s)
Carbon Dioxide/blood , End Stage Liver Disease/surgery , Liver Transplantation/methods , Monitoring, Intraoperative/methods , Myelin Sheath/diagnostic imaging , Optic Nerve/diagnostic imaging , Perfusion , Adult , Biomarkers/blood , Cerebrovascular Circulation , End Stage Liver Disease/diagnosis , End Stage Liver Disease/physiopathology , Female , Humans , Intracranial Pressure , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , ROC Curve , Time Factors , Ultrasonography
5.
Transplant Proc ; 45(1): 245-50, 2013.
Article in English | MEDLINE | ID: mdl-23375309

ABSTRACT

BACKGROUND: Regional oxygen saturation (rSO(2)) is a sensitive marker of cerebral hypoperfusion during liver transplantation. However, bilirubin absorbs near-infrared light, resulting in falsely low rSO(2) values. We sought to determine whether rSO(2) values vary in response to bilirubin concentrations during liver transplantation and to assess whether rSO(2) changes were associated with factors reflecting cerebral oxygen delivery in patients with hyperbilirubinemia. METHODS: Measurements of rSO(2) values continuous cardiac output (CO), mean arterial pressure, central venous pressure, body temperature, arterial blood gas analysis, and laboratory parameters were simultaneously performed at 1 hour after the surgical incision (baseline) and at 3 predetermined times during the anhepatic and neohepatic phases in 95 end-stage liver disease patients including 67 males of Child A/B/C/29/29/37 categories respectively. Relationships between changes in parameters were evaluated by correlation and multivariate regression analyses. RESULTS: The 273 measurements revealed changes in rSO(2) (range, -18% to 40%) to correlate significantly with alterations in hemoglobin (Hb), serum glucose, lactate, prothrombin time, pH, partial arterial CO(2) pressure (PaCO(2)), and CO, but not with serum total bilirubin (TB). Multivariate linear regression analysis revealed that changes in Hb, CO, PaCO(2), and pH were independent of rSO(2) changes during liver transplantation. CONCLUSIONS: Our findings showed that rSO(2) changes were independently associated with factors reflecting cerebral oxygen delivery, such as Hb, CO, PaCO(2), and pH, whereas rSO(2) values did not correlate with changes in bilirubin concentrations, indicating that rSO(2) changes reveal cerebral oxygen balance regardless of TB levels among patients undergoing liver transplantation.


Subject(s)
Liver Failure/surgery , Liver Transplantation/methods , Oxygen/metabolism , Adult , Aged , Cardiac Output , Cerebrovascular Circulation/physiology , Female , Humans , Hydrogen-Ion Concentration , Hyperbilirubinemia/metabolism , Magnetic Resonance Angiography , Male , Medical Records Systems, Computerized , Middle Aged , Perfusion , Regression Analysis , Spectroscopy, Near-Infrared
6.
Transplant Proc ; 44(5): 1318-22, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22664008

ABSTRACT

BACKGROUND: The role of B-type natriuretic peptide (BNP) concentration in predicting cardiac dysfunction has been extensively investigated in many clinical conditions. Little is known, however, about its relationships with hemodynamic parameters from right heart catheterization in patients undergoing liver transplant surgery. METHODS: We retrospectively evaluated 525 patients who underwent liver transplantation. Hemodynamic variables from a Swan-Ganz catheter and BNP concentrations were measured 1 hour after induction of general anesthesia. Patients were stratified by quintiles of BNP concentrations. Univariate and multivariate logistic regression analysis were used to identify hemodynamic parameters associated with BNP ≥ 135 pg/mL, a cutoff point for the 5th quintile. RESULTS: Univariate analysis showed that factors significantly associated with BNP ≥ 135 pg/mL included model for end-stage liver disease (MELD) score, diastolic blood pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure (PCWP), cardiac index, right ventricular end-diastolic volume index (RVEDVI), systemic vascular resistance index, pulmonary vascular resistance index (PVRI), and right ventricular stroke work index. Multivariate analysis revealed that MELD score (odds ratio [OR] = 1.059, P < .001), PCWP (OR = 1.116, P = .026), RVEDVI (OR = 1.010, P = .009), and PVRI (OR = 1.009, P = .002) were independent determinants of BNP ≥ 135 pg/mL. CONCLUSIONS: Severity of liver disease, preload dependent hemodynamic parameters, and pulmonary vascular resistance were found to be significantly associated with increased BNP concentration, reinforcing the utility of BNP as a marker of cardiac strain and ventricular volume overload in liver failure patients undergoing liver transplant surgery.


Subject(s)
End Stage Liver Disease/surgery , Hemodynamics , Liver Transplantation , Monitoring, Intraoperative , Natriuretic Peptide, Brain/blood , Biomarkers/blood , Catheterization, Swan-Ganz , Chi-Square Distribution , End Stage Liver Disease/blood , End Stage Liver Disease/physiopathology , Female , Heart Diseases/blood , Heart Diseases/etiology , Heart Diseases/physiopathology , Humans , Liver Transplantation/adverse effects , Logistic Models , Male , Middle Aged , Monitoring, Intraoperative/methods , Multivariate Analysis , Odds Ratio , Republic of Korea , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Up-Regulation , Vascular Resistance
7.
Transplant Proc ; 43(5): 1407-11, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21693206

ABSTRACT

BACKGROUND: Although stroke volume variation (SVV) is a valuable index of preload responsiveness, there is limited information about the association between low SVV and increased hepatectomy-related bleeding. We therefore evaluated whether SVV predicts blood loss during living donor hepatectomy. METHODS: We evaluated 93 adult liver donors undergoing right hepatectomy for transplantation. Arterial blood pressure, heart rate, body temperature, central venous pressure, SVV, cardiac output, and systemic vascular resistance were measured. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to determine independent factors and optimal cutoff values of hemodynamic parameters for predicting intraoperative blood loss ≥ 700 mL. RESULTS: Of these 93 donors, 36 (38.7%) had blood loss ≥ 700 mL. Univariate logistic regression analysis showed that factors associated with blood loss ≥ 700 mL included heart rate, SVV, cardiac output, and systemic vascular resistance. Multivariate logistic regression analysis revealed that only SVV was an independent predictor of blood loss ≥ 700 mL. ROC curve analysis showed that the optimal cutoff value for SVV predicting blood loss ≥ 700 mL was 6% (area under the curve = 0.64). CONCLUSIONS: SVV is a significant independent predictor of blood loss ≥ 700 mL during donor hepatectomy, suggesting that low SVV may provide useful information on intraoperative bleeding in donors undergoing right hepatectomy.


Subject(s)
Blood Loss, Surgical , Liver Transplantation , Living Donors , Stroke Volume , Adult , Blood Pressure , Body Temperature , Female , Heart Rate , Humans , Male , ROC Curve
8.
Transplant Proc ; 43(5): 1654-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21693252

ABSTRACT

BACKGROUND: Prolonged corrected QT (QT(c)) interval and vagal dysfunction are common occurrences in liver cirrhosis and are determinants of mortality in patients with chronic liver disease. We evaluated whether propranolol can affect the relationship between QT(c) interval and cardiac vagal control of heart rate variability (HRV) in cirrhotic patients awaiting liver transplantation. METHODS: We compared 50 cirrhotic patients (M/F = 43/7, 52.6 ± 8.4 years, Child-Pugh class A/B/C: 9/24/17) receiving propranolol with a sex-, age-, and liver disease severity-matched control group of 50 patients (M/F = 43/7, 52.0 ± 8.3 year, Child-Pugh class A/B/C: 9/24/17) not receiving propranolol. Among the parameters evaluated were QT(c) interval and cardiac vagal indices of HRV, including the root mean square of successive differences in R-R intervals (RMSSD); spectral power in the high-frequency range (HF); standard deviation (SD)1 in Poincare plot; and sample entropy. Correlations between QT(c) interval and vagal indices of HRV were analyzed. RESULTS: The mean duration of preoperative propranolol treatment in the propranolol group was 19.4 ± 24.7 months. QT(c) interval was significantly lower, whereas RMSSD, HF, SD1, and sample entropy were significantly higher in the propranolol group than in the control group. Correlation coefficients between QT(c) interval and RMSSD, HF, SD1, and sample entropy were higher in the propranolol group than in the control group. CONCLUSIONS: The prolonged QT(c) interval observed in cirrhotic patients may be reduced by propranolol administration, an effect attributable to improved vagal cardiac modulation. These findings suggest that propranolol may have a beneficial effect on perioperative mortality in cirrhotic patients awaiting liver transplantation.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Heart Rate/drug effects , Liver Cirrhosis/physiopathology , Liver Transplantation , Propranolol/pharmacology , Adult , Electrocardiography , Female , Humans , Male , Middle Aged
9.
Transplant Proc ; 43(5): 1684-90, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21693258

ABSTRACT

BACKGROUND: Although brain natriuretic peptide (BNP), a marker of cardiac dysfunction, has been known to predict postoperative mortality, little is known about the postoperative prognostic ability of BNP in liver transplantation (OLT) recipients. We aimed to determine whether intraoperative BNP level can predict 1-year all-cause mortality after OLT. METHODS: We retrospectively investigated 525 OLT recipients. BNP and hemodynamic parameters were simultaneously measured 1 hour after induction of anesthesia. Cox regression analysis and receiver operating characteristic curve analysis were performed to determine clinical predictors and optimal cutoff values of post-OLT mortality. RESULTS: The 1-year all-cause mortality rate was 9.7% (51/525). Median BNP concentration was significantly higher in nonsurvivors than in survivors (114 vs 56 pg/mL, P < .001). Significant factors in univariate Cox regression analysis were Child-Pugh score, model for end-stage liver disease (MELD) score, logBNP, hemoglobin, creatinine, heart rate, systolic pulmonary arterial pressure, and central venous pressure. In multivariate Cox regression analysis, independent predictors of posttransplant mortality were MELD score and logBNP. However, simultaneously measured hemodynamic parameters did not remain predictors. BNP levels greater than a cutoff of 136 pg/mL (specificity = 83.5%, negative predictive value = 93.6%) were associated with increased post-OLT mortality (log-rank test P < .001). CONCLUSIONS: Intraoperative BNP level is an independent predictor of 1-year all-cause mortality after OLT with a high negative predictive value, suggesting that its measurement appears useful in identifying patients at low risk of post-OLT mortality.


Subject(s)
Biomarkers/blood , Liver Transplantation/mortality , Natriuretic Peptide, Brain/blood , Female , Humans , Intraoperative Period , Male , Middle Aged , Prognosis , ROC Curve
10.
Transplant Proc ; 43(1): 170-3, 2011.
Article in English | MEDLINE | ID: mdl-21335179

ABSTRACT

BACKGROUND: QT interval prolongation, predisposing to ventricular tachyarrhythmia, has frequently been observed in patients with liver cirrhosis. During liver transplantation (LT) surgery, electrolyte imbalance and hemodynamic instability may affect QT interval changes. We evaluated the alterations in QT parameters at each stage of LT surgery. METHODS: We assessed 50 living donor LT recipients without overt heart disease for the corrected QT (QTc) and the interval from peak to the end of the T wave (T(p-e)) automatically using Bazett's formula with LabChart software. QT parameters, laboratory and hemodynamic data were simultaneously collected in the following stages of LT: before anesthetic induction (baseline), pre-anhepatic, anhepatic, 1 hour postreperfusion, and after hepatic artery anastomosis. Recipients were allocated into 2 groups according to their baseline QTc: ≥440 versus <440 msec. RESULTS: QTc progressively rose from the pre-anhepatic stage remaining prolonged in each stage of LT surgery compared with the baseline. In the anhepatic stage, 54% of recipients showed marked prolongation of QTc ≥500 msec (522 ± 14), which indicated the potential for a fatal ventricular dysrhythmia: 77% and 36% in groups with QTc ≥440 and <440 msec, respectively. As opposed to changes in QTc, T(p-e) in the anhepatic stage decreased significantly; however, it returned to the baseline level in the neohepatic stage. CONCLUSION: A prolonged QTc interval (≥500 msec) was frequently observed throughout the procedure of LT, even among patients with baseline QTc <440 msec, emphasizing the importance of optimizing electrolyte balance and hemodynamic status to reduce greater risk of perioperative arrhythmias.


Subject(s)
Electrocardiography , Liver Transplantation , Living Donors , Female , Humans , Male , Middle Aged
11.
Acta Anaesthesiol Scand ; 55(5): 558-64, 2011 May.
Article in English | MEDLINE | ID: mdl-21342149

ABSTRACT

BACKGROUND: Hyperlactatemia can predict the prognosis of patients undergoing liver resection. The effects of lactated Ringer's solution on liver function have not been evaluated in patients undergoing major liver resection. We therefore compared the effects of two different crystalloid solutions, with and without lactate, on liver function test data and serum lactate level in living donors undergoing right hepatectomy. METHODS: A total of 104 donors undergoing right hepatectomy for liver transplantation were randomly allocated to receive lactated Ringer's (LR) solution (n=52) or Plasmalyte (n=52). Anesthetic and fluid management were standardized. Acid-base status, lactate concentration, and liver function tests were analyzed at predetermined time points during the first 5 post-operative days. RESULTS: The lactate concentrations were significantly higher in the LR group than in the Plasmalyte group 1 h after hepatectomy [4.2 (3.2-5.7) vs. 3.3 (2.6-4.6) mmol/l; P=0.005, median (interquartile ranges)]. In addition, the nadir concentration of albumin was significantly lower and the peak total bilirubin concentration and prothrombin time were significantly higher in the LR group compared with the Plasmalyte group. However, these changes in the LR group subsided within the first or second post-operative days, without apparent complications or prolongation of hospital stay. Post-operative peak concentrations of lactate were not correlated with nadir albumin concentration, peak bilirubin, or peak prothrombin time, in either group. CONCLUSION: This prospective randomized study showed that non-lactate-containing crystalloid solution may have important advantages over LR solution, concerning lactate and liver profiles, in living donors undergoing right hepatectomy.


Subject(s)
Hepatectomy , Isotonic Solutions/therapeutic use , Lactates/blood , Lactates/therapeutic use , Liver Function Tests , Living Donors , Plasma Substitutes/therapeutic use , Acid-Base Equilibrium , Adult , Anesthesia, General , Crystalloid Solutions , Female , Gluconates/therapeutic use , Humans , Magnesium Chloride/therapeutic use , Male , Postoperative Period , Potassium Chloride/therapeutic use , Prospective Studies , Ringer's Solution , Serum Albumin/metabolism , Sodium Acetate/therapeutic use , Sodium Chloride/therapeutic use , Solutions , Tissue and Organ Harvesting , Young Adult
12.
Transplant Proc ; 42(7): 2430-5, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20832521

ABSTRACT

BACKGROUND: Hepatic resection may be associated with postoperative coagulopathy. However, there is limited information about the predictors affecting coagulopathy after donor hepatectomy. We evaluated the contributors of maximal changes in prothrombin time (PT), activated thromboplastin time (aPTT), and platelet count in the development of postoperative coagulopathy. METHODS: We retrospectively analyzed 864 living donors, all of whom received general anesthesia using desflurane, isoflurane, or sevoflurane. A coagulation derangement was defined as one or more of the following events postoperatively: peak PT >1.5 international normalized ratio (INR; highest quartile of PT), peak aPTT >46 seconds (highest quartile of aPTT), or nadir platelet count <100 × 10(9)/L. Factors were evaluated by univariate and multivariate logistic regression analysis to identify predictors of coagulopathy. RESULTS: Mean postoperative peak PT, peak aPTT, and nadir platelet count were 1.4 ± 0.2 INR, 43.8 ± 23.7 seconds, and 155.9 ± 37.3 × 10(9)/L, respectively, with 39.4% of donors being at the risk for coagulation derangement. Multivariate logistic regression analysis revealed that predictors of such derangement included anesthesia duration, remnant liver volume, and body mass index (BMI). However, coagulation derangement was not independently associated with age, gender, volatile anesthetics, central venous pressure, fatty change in the liver, estimated blood loss, or intraoperative hypotensive episodes. CONCLUSION: We found that long anesthesia duration, low BMI, and small remnant liver volume were predictors of coagulation derangement. These results provide a better understanding of risk factors affecting changes in coagulation profiles after living donor hepatectomy.


Subject(s)
Blood Coagulation Disorders/etiology , Blood Coagulation/physiology , Hepatectomy/methods , Living Donors , Adolescent , Adult , Aged , Blood Pressure , Cholecystectomy , Female , Humans , International Normalized Ratio , Male , Middle Aged , Partial Thromboplastin Time , Postoperative Complications/blood , Retrospective Studies
13.
Transplant Proc ; 42(7): 2585-9, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20832549

ABSTRACT

BACKGROUND: Dynamic preload indices such as stroke volume variation (SVV) and pulse pressure variation (PPV) have yielded false-positive results in patients with right ventricular (RV) dysfunction. We therefore assessed the effect of RV dysfunction on dynamic indices to predict the decrease in cardiac output (CO) during liver transplantation. METHODS: Hemodynamic parameters were measured before and after inferior vena cava (IVC) clamping in 52 recipients. The RV dysfunction was defined as an RV ejection fraction (RVEF) ≤ 30%. The area under the receiver operating characteristic curve (AUC) sufficient to detect changes in CO (ΔCO) ≥ 20% after IVC clamping in recipients was calculated. RESULTS: Recipients with RVEF ≤ 30% did not show significant increases in SVV or PPV despite having ΔCO ≥ 20%. In recipients with RVEF > 30%, the threshold value and AUC of SVV predicting a decrease in CO were 10% and 0.755 (compared with an AUC of 0.5, P = .011), respectively, whereas those for PPV were 10% and 0.767 (P = .007), respectively. However, in recipients with RVEF ≤ 30%, the threshold value and AUC of SVV were 10% and 0.638 (P = .305), respectively, whereas those for PPV were 12% and 0.684 (P = .159), respectively. CONCLUSIONS: These results suggest that dynamic preload indices may not be sufficiently sensitive to detect a CO decrease in liver transplant recipients with RV dysfunction, emphasizing the importance of evaluating RV function when determining the predictability of dynamic indices.


Subject(s)
Cardiac Output/physiology , Liver Transplantation/physiology , Stroke Volume/physiology , Ventricular Dysfunction, Right/physiopathology , Adult , Blood Pressure Determination , Constriction , Electrocardiography , Female , Heart Ventricles/physiopathology , Hemodynamics , Hepatitis B/complications , Humans , Liver Cirrhosis/surgery , Liver Cirrhosis/virology , Liver Transplantation/methods , Male , Middle Aged , Monitoring, Physiologic , Oximetry , Vena Cava, Inferior/physiopathology , Ventricular Dysfunction, Right/etiology
14.
Transplant Proc ; 42(7): 2791-3, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20832589

ABSTRACT

Liver transplantation (LT) is an effective treatment option in patients with Budd-Chiari syndrome and end-stage liver disease. However, the procedure may lead to a sudden increase in cardiac preload, which in turn may cause heart failure. Although assays of B-type natriuretic peptide (BNP) are increasingly used in diagnosis, management, and prediction of heart failure, the role of BNP after LT has not been well defined. Herein, we describe the case of a 56-year-old woman with Budd-Chiari syndrome who underwent LT and in whom heart failure was successfully managed using serial monitoring of BNP concentrations. The BNP concentration increased to 1735 pg/mL on postoperative day 4, and decreased to 180 pg/mL on postoperative day 19, at which time inotropic agents were discontinued.


Subject(s)
Budd-Chiari Syndrome/surgery , Heart Failure/therapy , Liver Transplantation/adverse effects , Natriuretic Peptide, Brain/blood , Blood Pressure , Cardiotonic Agents/therapeutic use , Female , Heart Failure/drug therapy , Heart Failure/physiopathology , Heart Rate , Humans , Liver Cirrhosis/surgery , Liver Function Tests , Middle Aged , Monitoring, Physiologic/methods , Vascular Resistance
15.
Transplant Proc ; 41(10): 4220-8, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20005373

ABSTRACT

BACKGROUND: Stroke volume variation (SVV) is being increasingly used to predict fluid responsiveness. Since radial arterial pressure (RAP) and femoral arterial pressure (FAP) frequently showing discrepancies during liver transplantation (LT), we sought to investigate the effect of differing arterial waveforms on SVV and cardiac output (CO) derived from the Vigileo device, by comparing SVV and CO values derived from RAP (SVV(RAP), CO(RAP)) and FAP (SVV(FAP), CO(FAP)) during LT. METHODS: The linear associations and agreements between SVV(RAP) and SVV(FAP) and between CO(RAP) and CO(FAP) were assessed during LT. Hemodynamic variables were measured at nine predefined time points in all 32 recipients, resulting in 288 data pairs. RESULTS: Correlations were observed between SVV(RAP) and SVV(FAP) (r = .961) and between CO(RAP) and CO(FAP) (r = .848) at all time points. These correlations between SVV(RAP) and SVV(FAP) (r = .923) and between CO(RAP) and CO(FAP) (r = .902) existed even during the period when mean RAP and FAP values differed (10 minutes after reperfusion). Bland-Altman analysis for SVV(RAP) versus SVV(FAP) and for CO(RAP) versus CO(FAP) showed weak biases (-0.2% and -0.5 L/min) and reasonable limits of agreement (-2.2 to 1.8% and -1.9 to 0.9 L/min). The percentage errors for SVV and CO values were 27.0% and 22.2%. CONCLUSIONS: There was no significant difference between SVV(RAP) and SVV(FAP) when measured using the Vigileo device during LT. This finding indicated that SVV obtained using the Vigileo device offered relatively consistent information regardless of the catheterization site.


Subject(s)
Cardiac Output/physiology , Femoral Artery/physiopathology , Liver Failure, Acute/surgery , Liver Transplantation/physiology , Monitoring, Intraoperative/methods , Radial Artery/physiopathology , Stroke Volume/physiology , Adult , Blood Pressure/physiology , Body Height , Body Weight , Female , Heart Rate/physiology , Humans , Liver Failure, Acute/physiopathology , Living Donors , Male , Middle Aged
16.
Transplant Proc ; 41(5): 1979-81, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19545773

ABSTRACT

Aggravation of mitral regurgitation (MR) due to left ventricular outflow tract obstruction (LVOTO) is likely to occur during liver transplantation in cirrhotic patients with hypertrophic cardiomyopathy (HCMP). Moreover, calcium administration following severe hypocalcemia due to inadequate citrate metabolism and massive transfusion may induce MR aggravation with LVOTO in such patients. Herein we have described a cirrhotic patient with HCMP in whom MR was aggravated due to LVOTO resulting from inadvertent rapid administration of calcium during liver transplantation.


Subject(s)
Calcium Chloride/adverse effects , Cardiomyopathy, Hypertrophic/complications , Intraoperative Complications/chemically induced , Liver Transplantation/methods , Mitral Valve Insufficiency/chemically induced , Ventricular Outflow Obstruction/chemically induced , Echocardiography, Transesophageal , Female , Hemodynamics/drug effects , Hemodynamics/physiology , Humans , Hypocalcemia/drug therapy , Hypocalcemia/etiology , Middle Aged , Treatment Outcome
17.
Br J Ophthalmol ; 93(6): 759-64, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19304584

ABSTRACT

BACKGROUND/AIMS: To report the clinical significance of late geographic hyperfluorescence (LGH) on indocyanine green angiography (ICGA) in cases of polypoidal choroidal vasculopathy (PCV). METHODS: The medical records of 43 eyes with PCV, all of which had undergone at least 12 months of follow-up, 40 eyes with exudative age-related macular degeneration (AMD) and 20 eyes of age-matched normal subjects were retrospectively analysed. The incidence of LGH, defined as a well-demarcated geographic hyperfluorescent lesion on late phase ICGA, was compared in each respective group. The natural course of the LGH and its changes after photodynamic therapy (PDT) were analysed. RESULTS: LGH was noted in all of the eyes with PCV, whereas LGH was noted in three eyes (7.5%) of the eyes with exudative AMD and was not noted in any of the normal subjects (p<0.01). Of the 27 eyes (62.8%) with PCV, LGH was matched to the total area of the branching vascular network and polyps. The extent of LGH was enlarged over time in approximately one-half of the cases. As compared with the eyes demonstrating persistent LGH after PDT, the eyes with fading or disappearing LGH evidenced a lower recurrence of active PCV (p<0.05). CONCLUSION: LGH is a highly sensitive and specific ICGA finding for the diagnosis of PCV. Increased surveillance should be implemented in eyes in which LGH persists after PDT.


Subject(s)
Choroid Diseases/diagnosis , Polyps/diagnosis , Adult , Aged , Aged, 80 and over , Choroid/blood supply , Choroid Diseases/drug therapy , Choroidal Neovascularization/diagnosis , Choroidal Neovascularization/drug therapy , Coloring Agents , Diagnosis, Differential , Female , Fluorescein Angiography/methods , Humans , Indocyanine Green , Macular Degeneration/diagnosis , Male , Middle Aged , Photochemotherapy , Polyps/drug therapy , Recurrence , Retrospective Studies , Treatment Outcome
18.
Anesth Analg ; 91(3): 698-701, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10960403

ABSTRACT

UNLABELLED: We evaluated whether a thermosoftening treatment with warm saline of a nasotracheal preformed tube can improve navigability through the nasal passageways and reduce epistaxis and nasal damage. A total of 150 patients were randomly allocated to three groups: Group I (untreated tube group, n = 50), Group II (35 degrees C treated tube group, n = 50), and Group III (45 degrees C treated tube group, n = 50). In Groups II and III, the tubes were softened at 35 +/- 2 degrees C and 45 +/- 2 degrees C with warm saline, respectively. In Group I the tube was prepared at room temperature (25 +/- 2 degrees C). The incidence of epistaxis and nasal damage in Groups II and III was significantly less than that of Group I (P: < 0.05). Despite the more frequent incidence of smooth passage in Group III, no statistical difference was found among the groups. Logistic regression analysis also confirmed that epistaxis was more likely to be reduced when the tube had been thermosoftened (odds ratio = 1.46, 95% confidence interval = 1.02, 2.11). We conclude that simple thermosoftening treatment of the nasotracheal tube with warm saline helps to reduce epistaxis and nasal damage. IMPLICATIONS: Thermosoftening treatment of a nasotracheal tube with warm saline before intubation can effectively reduce epistaxis and nasal damage. This technique is safe, easy, and suitable for all types of tubes and does not require additional implements.


Subject(s)
Epistaxis/prevention & control , Intubation, Intratracheal/adverse effects , Intubation, Intratracheal/instrumentation , Nose/injuries , Adult , Female , Hot Temperature , Humans , Male , Middle Aged
19.
J Laparoendosc Adv Surg Tech A ; 9(3): 277-81, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10414546

ABSTRACT

We present two cases of sudden unanticipated cardiovascular complications in patients with noncatecholamine-secreting adrenocortical adenomas during laparoscopic adrenalectomy. In the first case, the patient developed paroxysmal tachycardia and hypertension followed by ventricular fibrillation shortly after clipping of the adrenal vein. In the second case, the patient suffered hypertension and bigeminy during manipulation of the adrenal gland just around the adrenal vein. Awareness of such complications during either conventional or laparoscopic adrenalectomy is important even if the operation is performed in a patient with an apparently noncatecholamine-secreting adrenocortical adenoma.


Subject(s)
Adenoma/complications , Adrenal Cortex Neoplasms/complications , Hypertension/etiology , Tachycardia, Paroxysmal/etiology , Ventricular Fibrillation/etiology , Adenoma/metabolism , Adenoma/surgery , Adrenal Cortex/blood supply , Adrenal Cortex/metabolism , Adrenal Cortex/surgery , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/surgery , Adrenalectomy/adverse effects , Adult , Catecholamines/metabolism , Female , Humans , Intraoperative Complications/diagnosis , Laparoscopy , Veins
20.
J Allergy Clin Immunol ; 103(6): 1195-201, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10359906

ABSTRACT

BACKGROUND: Cow's milk-sensitive enteropathy (CMSE) is an important cause of chronic diarrhea and failure to thrive in infancy. The immunopathology of the mucosal lesion associated with CMSE has not yet been described. OBJECTIVES: This study investigated the eosinophil activation and the role of adhesion molecules in the pathogenesis of intestinal mucosal damage associated with CMSE. METHODS: Twenty-one patients with chronic diarrhea and abnormal mucosa on duodenal biopsy specimens were included. The patients had negative responses to skin prick tests and RASTs with milk. Fourteen patients were diagnosed with CMSE by milk challenge test and were designated as the CMSE group. Seven patients with no milk intolerance were defined as the non-CMSE group. Four infants with frequent vomiting and no mucosal abnormalities were also studied as the control group. Immunohistochemical stains for eosinophil major basic protein (MBP), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 on endoscopic duodenal biopsy specimens were performed. RESULTS: The degree of eosinophil degranulation, as evidenced by localization of extracellular MBP, was significantly greater in the CMSE group compared with the non-CMSE and control groups (P <.05). Expression of VCAM-1 on mononuclear cells was higher in the CMSE group compared with the non-CMSE and control groups (P <.05). The severity of villous atrophy was positively correlated with the deposition of MBP (r = 0.79, P <.001). CONCLUSION: These results strongly suggest eosinophils and VCAM-1 are implicated in the pathogenesis of mucosal damage associated with CMSE.


Subject(s)
Blood Proteins/metabolism , Inflammation Mediators/metabolism , Intercellular Adhesion Molecule-1/biosynthesis , Intestinal Mucosa/metabolism , Milk Hypersensitivity/complications , Vascular Cell Adhesion Molecule-1/biosynthesis , Biopsy , Duodenum/pathology , Eosinophil Granule Proteins , Eosinophils/chemistry , Humans , Infant , Infant, Newborn , Intestinal Diseases/etiology , Intestinal Diseases/immunology , Monocytes/chemistry , Ribonucleases
SELECTION OF CITATIONS
SEARCH DETAIL
...