Pretransplantation Cystatin C, but not Creatinine, Predicts 30-day Cardiovascular Events and Mortality in Liver Transplant Recipients With Normal Serum Creatinine Levels.

BACKGROUND: The connection between renal dysfunction and cardiovascular dysfunction has been consistently shown. In patients with liver cirrhosis, renal dysfunction shows a tight correlation with prognosis after liver transplantation (LT); therefore, precise renal assessment is mandatory. Cystatin C, a sensitive biomarker for assessing renal function, has shown superiority in detecting mild renal dysfunction compared to classical biomarker creatinine. In this study, we aimed to compare cystatin C and creatinine in predicting 30-day major cardiovascular events (MACE) and all-cause mortality in LT recipients with normal serum creatinine levels. PATIENTS AND METHODS: Between May 2010 and October 2015, 1181 LT recipients (mean Model for End-stage Liver Disease score 12.1) with pretransplantation creatinine level ≤1.4 mg/dL were divided into tertiles according to each renal biomarker. The 30-day MACE was a composite of troponin I >0.2 ng/mL, arrhythmia, congestive heart failure, death, and cerebrovascular events. RESULTS: The highest tertile of cystatin C (≥0.95 mg/L) was associated with a higher risk for a 30-day MACE event (odds ratio: 1.62; 95% confidence interval: 1.07 to 2.48) and higher risk of death (hazard ratio: 1.96; 95% confidence interval: 1.04 to 3.67) than the lowest tertile (<0.74 mg/L) after multivariate adjustments. However, the highest tertile of creatinine level showed neither increasing MACE event rate nor worse survival rate compared with the lowest tertile (both insignificant after multivariate adjustment). CONCLUSIONS: Pretransplantation cystatin C is superior in risk prediction of MACE and all-cause mortality in LT recipients with normal creatinine, compared to creatinine. It would assist further risk stratification which may not be detected with creatinine.

Application of the Revised Cardiac Risk Index to the Model for End-Stage Liver Disease Score Improves the Prediction of Cardiac Events in Patients Undergoing Liver Transplantation.

INTRODUCTION: Although the revised cardiac risk index (RCRI) is a useful tool for estimating the risk of postoperative cardiac events, whether it improves the prediction of cardiac events in patients undergoing liver transplantation (LT) has not been sufficiently demonstrated. METHODS: We retrospectively analyzed 1429 patients who underwent LT. Cardiac events were defined as myocardial infarction, death, or combined events within 30 days after surgery. The RCRI was defined as the number of independent predictors including high-risk surgery, ischemic heart disease, congestive heart failure, cerebrovascular disease, insulin treatment, and creatinine level >2 mg/dL. Multivariate logistic regression analysis was performed to identify factors independently associated with cardiac events. The additive predictability of RCRI for the Model for End-Stage Liver Disease (MELD) score was assessed using receiver operating characteristic curve analysis. RESULTS: Forty-four (3.1%) cardiac events occurred within 30 days after surgery. Both the MELD score (adjusted odds ratio [aOR], 1.05; P = .005) and RCRI (aOR, 4.35; P < .001 for RCRI score 2; aOR, 6.27; P = .009 for RCRI score 3 compared with RCRI score 1) independently predicted postoperative 30-day cardiac events. The model with MELD score plus RCRI was significantly more predictive for postoperative 30-day cardiac events than the model with MELD score alone (C-statistics 0.800 vs 0.757; P = .030). CONCLUSIONS: For preoperative risk stratification, RCRI showed additive value to MELD score in predicting postoperative 30-day cardiac events after LT.

Prevalence of Antiphospholipid Antibody Positivity and Association of Pretransplant Lupus Anticoagulant Positivity With Early Allograft Dysfunction in Liver Transplantation.

BACKGROUND: Antiphospholipid antibodies (aPL), including anticardiolipin (aCL), anti-ß2-glycoprotein I (anti-ß2GPI), and lupus anticoagulant (LA) antibodies, are frequently found in liver cirrhosis and associated with splanchnic vein thrombosis. Although the risk factors of early allograft dysfunction (EAD) are known, the association between EAD and aPL has been poorly investigated. We hypothesized that LA, potent aPL with thrombotic potential, may be associated with EAD development after living donor liver transplantation (LDLT). METHODS: Data of 719 patients who underwent LDLT from February 2014 to June 2016 at our center were retrospectively collected and analyzed. Patients were divided into 2 groups according to the positivity of LA screening test (LA group [n = 148] vs no-LA group [n = 571]). Risk factors for EAD were investigated using multivariable regression analysis and inverse probability of treatment weighting (IPTW) of propensity scores. RESULTS: The prevalence of LA screening positivity, confirmatory test positivity, and EAD was 20.6%, 1.1%, and 11.3%, respectively. aCL positivity rate was 7.5% and anti-ß2GPI positivity rate was 7.0%. The EAD prevalence in LA and no-LA group was 25.7% and 7.5%, respectively. However, multivariable and IPTW analyses showed no association between EAD and LA screening positivity (P = .263 and P = .825, respectively), although a significant association was found in univariate analysis (odds ratio, 4.242; P < .001). Model for End-stage Liver Disease score, operation time, and C-reactive protein level remained significant after multivariable analysis. CONCLUSION: A positive LA screening test result was associated with EAD only in the univariate analysis. Inflammation, based on C-reactive protein level, was more important for EAD development.

Does Activated Clotting Time Help to Predict Innate Coagulopathy in End-Stage Liver Disease Patients?

BACKGROUND: Measuring activated clotting time (ACT) is widely performed to monitor heparin therapy. Regardless of anticoagulant use, ACT is affected by coagulopathies such as coagulation factor deficiency and thrombocytopenia. However, its use in end-stage liver disease (ESLD) with complex coagulopathy is not well characterized. We evaluated whether ACT could be used to detect innate coagulopathy in ESLD patients. METHODS: We retrospectively assessed Hemochron (International Technidyne, Edison, NJ, USA) ACT (FTCA 510, normal range 105-167 seconds) and INTEM clotting time (CT) of rotational thromboelastometry (ROTEM; ROTEM delta, Pentapharm GmbH, Munich, Germany) (100-240 seconds) in 366 liver transplantation (LT) recipients, simultaneously measured before anesthetic induction for LT. Multiple linear regression analyses helped identify the factors related to ACT in ESLD patients. The relationship between ACT and INTEM CT was evaluated by Spearman rank correlation analysis and receiver operating characteristic curve. RESULTS: Median ACT was 143 seconds (range 73-295 seconds), and 60 patients (16.4%) had ACTs of >167 seconds. Multiple regression analyses revealed that prolonged prothrombin time, activated partial thromboplastin time, low antithrombin III, and young age were associated with high ACT levels. INTEM CT was associated with ACT independent of liver disease severity, while EXTEM CT was not. ACT was moderately correlated with INTEM CT (r = 0.535), and the optimal cutoff value of ACT for predicting INTEM CT >240 seconds was 151 seconds (area under the curve = 0.787). CONCLUSIONS: In ESLD patients, ACT is effective in detecting prolonged INTEM CT. Therefore, ACT may be used to predict intrinsic pathway defects with a cutoff value of 151 seconds, suggesting feasibility when ROTEM is unavailable.

Pretransplant Resting Heart Rate and Its Association With All-Cause Mortality in Liver Transplant Recipients.

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.

Pretransplant Left Ventricular Dysfunction Adversely Affects Perioperative Outcomes in Pediatric Liver Transplantation: A Retrospective Observational Study.

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.

Effect of stroke volume variation-directed fluid management on blood loss during living-donor right hepatectomy: a randomised controlled study.

Reducing blood loss is beneficial in living liver donor hepatectomy. Although it has been suggested that maintaining a low central venous pressure is important, it is known that low stroke volume variation may be associated with increased blood loss. Therefore, we compared the effect on blood loss of 40 patients randomly assigned to a high stroke volume variation group (maintaining 10-20% of stroke volume variation) vs 38 patients in a control group (maintaining < 10% stroke volume variation) during living-donor right hepatectomy. Mean (SD) blood loss during donor hepatectomy was significantly lower in the high stroke volume variation group than in the control group: 476 (131) ml vs 836 (341) ml, respectively (p < 0.001). Blood pressure and peri-operative laboratory values did not differ between the two groups. However, in the high stroke volume variation group, central venous pressure values were also significantly lower. We were unable to disentangle the effects of stroke volume variation and central venous pressure, but our results confirm that the two together appear beneficial.

Can stroke volume variation be an alternative to central venous pressure in patients undergoing kidney transplantation?

BACKGROUND: Stroke volume variation (SVV) is known to be a simple and less invasive hemodynamic parameter for evaluating fluid responsiveness and preload status. Central venous pressure (CVP) has been targeted to achieve an adequate level for improving the graft perfusion and long-term graft function in kidney transplantation (KT) recipients, despite the various potential complications. The aim of this study was to investigate whether SVV could substitute for CVP in guiding intravascular volume management during KT. METHODS: This retrospective study evaluated 635 patients who underwent KT because of end-stage renal disease. Hemodynamic variables including CVP and SVV were obtained before skin incision (T1), 5 minutes after iliac vein clamping (T2), and 10 minutes after renal graft reperfusion (T3). The ability of SVV to predict CVP level was investigated with receiver operating characteristic (ROC) curve analysis. RESULTS: CVPs were 6.0 ± 2.6, 8.6 ± 2.7, and 9.3 ± 2.5 mm Hg, and SVVs were 6.9 ± 3.0, 5.0 ± 2.1, and 4.3 ± 2.1% at T1, T2, and T3, respectively. ROC analysis showed that the discriminative power of SVV was fairly good with an area under the ROC curve of 0.70 (95% confidence interval, 0.67-0.72) for a CVP of 8 mm Hg, and that an optimal cutoff value of SVV was 6% as an alternative to CVP of 8 mm Hg during KT. CONCLUSIONS: SVV may replace CVP in the volume management of patients who have undergone KT. Our results suggest that SVV can guide volume management to improve graft perfusion at critical time points during KT.

Five-minute parameter of thromboelastometry is sufficient to detect thrombocytopenia and hypofibrinogenaemia in patients undergoing liver transplantation.

BACKGROUND: Early detection of coagulopathy is important to prevent bleeding during liver transplantation (LT). Rotation thromboelastometry (ROTEM(®)) provides the earliest parameter of clot amplitudes at 5 min (A5). We evaluated whether A5 correlates with platelet count (PLT) and fibrinogen concentration (Fib) and can predict thrombocytopenia and hypofibrinogenaemia in hypocoagulable patients undergoing living-donor LT (LDLT). METHODS: A total of 3446 retrospective ROTEM(®) measurements, including 1139 EXTEM, 1182 INTEM, and 1125 FIBTEM, with simultaneously measured PLT and Fib, were analysed during LDLT in 239 patients. The correlations between A5 and maximum clot firmness (MCF) index, PLT, and Fib were calculated. Receiver operating characteristic analysis with area under the curve (AUC) was used to assess A5 thresholds predictive of PLT and Fib. RESULTS: The median PLT was 47 000 mm(-3) and the median Fib was 100 mg dl(-1) during LDLT. The A5 parameters of EXTEM (A5EXTEM) and INTEM (A5INTEM) were highly correlated with MCF (r=0.96 and r=0.95, respectively), PLT (r=0.76 and r=0.77, respectively), and Fib (r=0.63 and r=0.64, respectively). A5 of FIBTEM (A5FIBTEM) was also correlated with MCF (r=0.91) and Fib (r=0.75). A5EXTEM thresholds of 15 and 19 mm predicted PLT<30 000 mm(-3) (AUC=0.90) and <50 000 mm(-3) (AUC=0.87), respectively, whereas A5FIBTEM 4 mm predicted Fib<100 mg dl(-1) (AUC=0.86). Biases from A5EXTEM and A5FIBTEM to their MCFs were 16.4 and 1.3 mm, respectively. CONCLUSIONS: A5 as an early variable of clot firmness is effective in detecting critically low PLT and Fib. A5 can therefore be a reliable fast index guiding transfusion therapy in hypocoagulable patients undergoing LDLT.

Factors affecting intraoperative changes in regional cerebral oxygen saturation in patients undergoing liver transplantation.

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.

Does stroke volume variation predict intraoperative blood loss in living right donor hepatectomy?

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.

Preoperative echocardiographic indices associated with elevated brain natriuretic peptide in liver transplant recipients.

BACKGROUND: Cardiac dysfunction may be present in patients with liver cirrhosis. Brain natriuretic peptide (BNP) concentration is a widely used biomarker for heart failure. We evaluated whether elevated BNP reflects cardiac dysfunction, as assessed by preoperative echocardiography, in liver transplant recipients. METHODS: We assessed 122 liver transplant recipients (94 males, 28 females; age, 50 ± 8 years). All underwent preoperative echocardiography, including measurements of heart chamber size, mass, ejection fraction, systolic pressure gradient between right ventricle and right atrium (PGsys [RV - RA]), mitral inflow velocities including early (E) and late (A) transmitral flow velocities, E/A, and deceleration time of E. Tissue Doppler imaging (TDI) was also performed to evaluate systolic (S'), early diastolic (E'), and late diastolic (A') myocardial velocities, E'/A', EAS index: E'/(A' × S'), and E/E'. Univariate and multivariate logistic regression analyses were performed to determine echocardiographic indices for predicting BNP ≥ 100 pg/mL. RESULTS: Of 122 recipients, 87 (71%) had BNP < 100 pg/mL (median, 32.0 pg/mL; interquartile range [IQR], 18.0-50.0), and 35 (29%) had BNP ≥ 100 pg/mL (median, 163.0 pg/mL; IQR, 136.0-479.0). Univariate analysis showed that E (P < .001), PGsys (RV-RA) (P < .001), and E/E' (P = .038) were significantly associated with BNP ≥ 100 pg/mL. Multivariate analysis showed that PGsys (RV - RA) was the only independent predictor of BNP ≥ 100 pg/mL (odds ratio, 1.171; 95% confidence interval, 1.091-1.258; P < .001). CONCLUSION: PGsys (RV - RA) is an echocardiographic index independently associated with BNP ≥ 100 pg/mL, suggesting that elevated BNP in patients with end-stage liver disease may reflect increased pulmonary arterial pressure, rather than systolic and diastolic dysfunction assessed by TDI.

Factors associated with changes in coagulation profiles after living donor hepatectomy.

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.

Effect of right ventricular dysfunction on dynamic preload indices to predict a decrease in cardiac output after inferior vena cava clamping during liver transplantation.

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.

Comparison of stroke volume variations derived from radial and femoral arterial pressure waveforms during liver transplantation.

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.

Association between central venous pressure and blood loss during hepatic resection in 984 living donors.

BACKGROUND: Although low central venous pressure (CVP) anesthesia has been used to minimize blood loss during hepatectomy, the efficacy of this technique remains controversial. We therefore assessed the association between blood loss and CVP during hepatic resection, and examined significant determinants associated with intraoperative hemorrhage during hepatectomy in living donors. METHODS: Between April 2004 and April 2008, 984 living donors who underwent a hepatic resection were assessed retrospectively. Univariate and multivariate analyses were performed to explore the relationships between intraoperative blood loss and several variables including CVP. RESULTS: The mean intraoperative blood loss was 691.3 +/- 365.5 ml. Only four donors required packed red blood cell transfusions (mean, 1.5 U). The mean duration of hepatic resection was 92.1 +/- 26.3 min. The mean, maximum, and minimum values of CVP measured during hepatectomy were 4.6 +/- 1.7, 5.3 +/- 1.8, and 4.0 +/- 1.8 mmHg, respectively, and were not significantly correlated with intraoperative blood loss. On multivariate analysis, predictors of hemorrhage were liver fatty change, gender, and body weight, but none of the mean CVP, surgeons, anesthesiologists, anesthesia duration, resected liver volume, hepatectomy type, systolic blood pressure, heart rate, or body temperature were significant. CONCLUSIONS: CVP during hepatic resection was not associated with intraoperative blood loss in living liver donors, suggesting that CVP may not be an important factor in predicting blood loss during hepatectomy in healthy subjects.

Using 100% oxygen does not alter the cardiovascular autonomic regulation during non-invasively simulated haemorrhage in healthy volunteers.

We tested the effect of 100% oxygen on heart rate (HR), arterial blood pressure (ABP), cardiac output (CO), stroke volume (SV), total peripheral resistance (TPR), HR variability (HRV), systolic blood pressure variability (SBPV) and baroreflex sensitivity (BRS) in 20 healthy volunteers during simulated haemorrhage induced by -40 mmHg lower body negative pressure (LBNP). HRV in the high frequency region (HRV HF), BRS, ABP and TPR were significantly increased, SBPV in the low frequency region (SBPV LF), CO and SV were unchanged, and HR was significantly decreased by 100% oxygen administration during normovolaemia. HRV HF, BRS, CO and SV were significantly decreased, SBPV LF and ABP were unchanged, and HR and TPR were significantly increased by LBNP during 21% or 100% oxygen administration. There were no significant differences in cardiovascular autonomic and haemodynamic responses to LBNP during 21% or 100% oxygen administration, suggesting that 100% oxygen does not alter normal cardiovascular autonomic responses during simulated haemorrhage.