Estimation of Standard Liver Volume for Liver Transplantation in the Chinese Population

Introduction

The accurate assessment of standard liver volume (SLV) is necessary for the safety of both the donor and the recipient in living donor liver transplantation. However, the accuracy of SLV formulas relates to cohorts or races. This study examined the accuracy of a simple linear formula versus previous formulas of SLV for Chinese adults.

Methods

Among 112 patients with normal liver, we created a new formula for SLV with stepwise regression analysis using the following variables: age, gender, body weight, body height, body mass index, and body surface area. The agreement between the actual liver volume (LV) and calculated LV using various formulas was prospectively evaluated among 63 living donors by paired-sample student's t-test and Lin's concordance correlation coefficient.

Results

A new formula was developed SLV (mL) = 949.7 × BSA (m²) − 48.3 × age − 247.4 where age was counted as 1 for those <40, 2 if 41-60, and 3 if >60 years old. The calculated LV using our formula showed no significant difference from the actual LV using the paired-samples student's t-test (P = .653). Lin's concordance correlation coefficient showed substantial agreement between estimated LV using our formula and actual LV. Furthermore, this study also observed an almost perfect agreement between our formula and the Yoshizumi et al formula.

Conclusion

Our formula, which accurately estimated LV among Chinese adults, may be applicable to adults of other ethnicitis.     

Estimation of Standard Liver Volume in Chinese Adult Living Donors

Aim

To determine a formula predicting the standard liver volume based on body surface area (BSA) or body weight in Chinese adults.

Materials and Methods

A total of 115 consecutive right-lobe living donors not including the middle hepatic vein underwent right hemi-hepatectomy. No organs were used from prisoners, and no subjects were prisoners. Donor anthropometric data including age, gender, body weight, and body height were recorded prospectively. The weights and volumes of the right lobe liver grafts were measured at the back table. Liver weights and volumes were calculated from the right lobe graft weight and volume obtained at the back table, divided by the proportion of the right lobe on computed tomography. By simple linear regression analysis and stepwise multiple linear regression analysis, we correlated calculated liver volume and body height, body weight, or body surface area.

Results

The subjects had a mean age of 35.97 ± 9.6 years, and a female-to-male ratio of 60:55. The mean volume of the right lobe was 727.47 ± 136.17 mL, occupying 55.59% ± 6.70% of the whole liver by computed tomography. The volume of the right lobe was 581.73 ± 96.137 mL, and the estimated liver volume was 1053.08 ± 167.56 mL. Females of the same body weight showed a slightly lower liver weight. By simple linear regression analysis and stepwise multiple linear regression analysis, a formula was derived based on body weight. All formulae except the Hong Kong formula overestimated liver volume compared to this formula.

Conclusions

The formula of standard liver volume, SLV (mL) = 11.508 × body weight (kg) + 334.024, may be applied to estimate liver volumes in Chinese adults.     

Sobh Formula: A New Formula for Estimation of Creatinine Clearance in Healthy Subjects and Patients with Chronic Renal disease

Backgrounds: Cockcroft–Gault formula overestimates creatinine clearance (Ccr) in obese or edematous patients. This limitation urged us to develop a new formula that can overcome the limitation of Cockcroft–Gault formula. Methods: We developed a new formula suitable for rapid bedside estimation of creatinine clearance in healthy adults and elderly persons and patients with chronic renal disease considering the surface area as a reliable factor for estimation of creatinine clearance. This cross sectional study included 182 individuals (healthy persons and patients with chronic kidney disease). Ccr was estimated by different methods including 24 hours urine collection, Cockcroft–Gault equation, and our new formula, and ^99mTc-DTPA isotope clearance which was considered as a standard method for comparison between the other methods.Results: Our new formula had a statistically significant higher correlation coefficient with the standard ^99mTc-DTPA isotope clearance for all groups included in this study (r=0.97) than either Cockcroft–Gault formula (r=0.90) or 24 hours urine collection method (r=0.88). Conclusion: Our formula is a step forward for a better bedside assessment of kidney function in both healthy individuals and patients with chronic kidney disease.     

In Situ Posterior Graft Segmentectomy for Large-for-Size Syndrome in Deceased Donor Liver Transplantation in Adults: A Case Report

Large-for-size syndrome (LFSS) is controversial in pediatric living donor liver transplantation patients and is associated with a poor graft outcome. Similar situations in deceased donor liver transplantation (DDLT) in adults have not been reported frequently, and there are no official guidelines worldwide. Deceased donation is extremely limited in Japan, and when a larger liver is allocated for a very sick small recipient in Japan, transplantation with a plan to address LFSS might be necessary. The patient is a 58-year-old female patient who had acute liver failure with coma. The graft-recipient weight ratio (GRWR) was 2.74%. Although the graft was enlarged by reperfusion, the intraoperative Doppler ultrasound, performed after reperfusion, showed sufficient graft in-flow and out-flow. However, when the liver graft was situated appropriately into the right phrenic space supported by the rib cage and diaphragm, the blood flow in the hepatic vein and portal vein was significantly reduced. Graft blood flow did not improve without removing it from the right subphrenic space. Therefore, we decided to perform an in situ graft posterior segmentectomy, so that the graft right lobe was properly accommodated in the patient's right subphrenic space. After the segmentectomy of the graft, an intraoperative Doppler sonogram showed significantly improved blood flow. LFSS could be a significant operative challenge in adult DDLT, especially in areas with limited chances of DDLT. In situ posterior segmentectomy in the demarcated area could be a solution for treating patients with LFSS.     

Beyond the Standard of Care: A New Model to Judge Medical Negligence

Background  

The term “standard of care” has been used in law and medicine to determine whether medical care is negligent. However, the precise meaning of this concept is often unclear for both medical and legal professionals.     

Syngeneic Living-Donor Liver Transplantation for Hemangioendothelioma: A Clinical Model for Studying Liver Regeneration

A 22-year-old Caucasian patient underwent living-donor liver transplantation (LDLT) for hepatic hemangioendothelioma in a healthy liver. The organ donor was his monozygotic twin brother. Surgery was uneventful in both donor and recipient, who received the same postoperative treatment (i.e. no immunosuppression for the recipient). Although both donor and recipient achieved a full liver function recovery, the volume of the recipient's graft increased much more than the donor's residual liver in the first postoperative month (1.6-fold vs. 1.2-fold). This different growth rate correlated with growth hormone (GH)/insulin growth factor (IGF) axis dynamics: the donor had significantly lower insulin-like growth factor 1 (IGF-1), insulin-like growth factor 2 (IGF-2) and insulin-like growth factor binding protein 3 (IGFBP-3) values than the recipient on postoperative days (POD) 3-30, although they had similar GH values. Other potential regenerative factors, e.g. tumor necrosis alpha, interleukin 6 (IL-6), insulin and C peptide did not correlate with liver regeneration rate. The particular endocrine picture of the graft may be explained by a modified GH-hepatocyte interaction due to cold ischemia during preservation resulting in a higher IGF production. Whether this is a potential molecular tool by means of which transplanted partial livers promote their regeneration remains to be seen in a larger number of patients.     

用包皮除去环施行成人包皮环切术

作者用包皮除去环行成人包皮环切术 80例 ,效果满意 ,报道如下。1　临床资料1 1　一般资料1999年 9月～ 2 0 0 1年 3月间对 80例包茎或包皮过长的门诊患者 ,用包皮除去环进行手术 ,其中包茎 2 4例 ,包皮过长5 6例 ;平均年龄 2 7( 15～ 63)岁。1 2　器械介绍　　韩国ＧＭ商社ＳＤＳ -2包皮除去环由内环、外环和弹力线三部件组成 ,其中内环的外侧面有环形凹槽 ,可将包皮用弹力线捆绑卡在其中。成人用内环直径分 2 0、2 2、2 4、2 6、2 8、30ｍｍ六种型号。1.3　手术方法及术后处理用 0 .5 %碘伏消毒 ,2 %利多卡因行阴茎根部浸润麻醉后 ,用两把…     

Chronic Kidney Disease-Epidemiology Formula and Model for End-Stage Liver Disease Score in the Assessment of Renal Function in Candidates for Liver Transplantation

Assessment of renal function in patients with end-stage liver disease (ESLD) awaiting liver transplantation (OLT) is critical. Various conditions may cause renal damage in ESLD. Renal and liver functions are intertwined due to splanchnic hemodynamic relationships; renal failure rarely occurs in patients without advanced decompensated cirrhosis. The recent literature suggests that evaluation of renal function should include an assessment of liver function. The aim of this study was to evaluate different methods to estimate glomerular filtration rate (GFR) in patient among ESLD candidates for OLT over 1 year. We also correlated renal and hepatic functions. Fifty-two cirrhotic patients Model for End-Stage Liver Disease [MELD] > 10) were enrolled in the study. All patients were evaluated at baseline and every 4 months (T1-T4) thereafter for 1 year. The GFR was calculated by creatinine clearance, and estimated by Cockroft and Gault, Modified Diet Renal Disease (MDRD) 4 and 6 variable and Chronic Kidney Disease-Epidemiology (CKD-EPI) formulae. Hepatic functions were evaluated by MELD score, albumin, bilirubin, and International Normalized Ratio (INR). We observed not statistically significant increase mean value of MELD score, bilirubin, serum creatinine, and blood urea nitrogen and a reduced serum sodium. There were no significant differences among various methods to evaluate GFR at each time over 1 year. We did not observe any association between renal and hepatic function, except at T4 for MELD and GFR estimated with MDRD 4 (P = .009) and 6 (P = .008) parameters or CKD-EPI (P = .036), and MELD and sodium (P = .001). Our results showed that evaluation of renal function in cirrhosis should include an evaluation of hepatic function. In our case, MDRD and CKD-EPI seemed to be the more accurate formulae to evaluate renal function in relation to hepatic function.     

Mathematical Model for a New Mode of Artificial Ventilation: Volume Assisted Pressure Supported Ventilation: A Comparative Study

Abstract: The patient submitted to artificial ventilation generally is connected to a high impedance flow source with controlled respiratory cycles to assure volume requirements or to a low impedance pressure source with spontaneous cycles to allow synchronization between his effort and system flow delivery. These two types of cycles represent the initial and final stages of artificial ventilation. The patient who needs a volume guarantee and at the same time presents unstable or insufficient inspiratory effort is difficult to manage with assisted cycles which are analogous to the controlled presence of a high impedance flow source. This paper presents a new approach where the respiratory cycles are obtained by the combination of flow and pressure sources using mathematical modeling. These cycles, named volume assisted pressure supported (VAPS) cycles, are compared with conventional assisted cycles showing a decrease in the patient work of breathing (WOB) during assisted ventilation. The theoretical results have been confirmed by clinical trials.     

Liver Transplantation in Pigs: A Model for Studying Reperfusion Injury

A model of orthotopic liver transplantation in pigs was developed to investigate reperfusion injury of the liver. To have direct access to the liver for organ monitoring a relaparotomy was performed 6 h after revascularization. The details of modification in anesthesia and surgical technique are given. Salient features of the technique include (1) the use of an extremely short cuff of the donor suprahepatic caval vein, (2) the use of a central venous catheter fixed in a hepatic vein, and (3) the use of an aortic graft for standardized arterial reconstruction. Twenty-nine transplantations were performed. The total anesthetic time was 13.28 ± 1.45 h and the operative time was 10.06 ± 0.77 h. The animals withstood this long procedure remarkably well.     

A Novel Bioreactor Design for In Vitro Reconstruction of In Vivo Liver Characteristics

Abstract: We have constructed a bioreactor aimed at imitating the three-dimensional micro- and macroenviron-ment of the liver. In vivo hepatocytes are arranged in plates of cell monolayers and are specifically attached with both sinusoidal surfaces to the space of Disse which contains extracellular matrix. Nonparenchymal cells are located on the other side of the space of Disse toward the sinusoid. For supporting monolayer hepatocytes with bipolar attachment to the extracellular matrix, we used a double gel culture technique that sandwiches hepatocytes between two layers of collagen. In double gel cultures, albumin production increases during an adaptive period to the in vitro environment. In contrast to conventional trol (4). We have studied a variety of cellular parameters such as cytochrome P450 3A expression (27), drug metabolism (27, 28), protein secretion, and morphology. In situ-like morphology and stable function was obtained in DG culture.     

A Porcine Model for the Study of Liver Regeneration

A technique of 65% partial hepatectomy in the pig is described. Thymidine kinase activity and mitotic index were used as indices of liver regeneration. Thymidine kinase activity increased from a baseline value of 1526 ± 256 to a maximum of 23992 ± 4966 dpm/mg protein on the third day after partial hepatectomy. The mitotic index also increased from 0–13.3 ± 1.66 on the third postoperative day. The indices of regeneration remained unchanged after sham operation     

Preformed Titanium Meshes: A New Standard?

Three-dimensional reconstruction of the orbital floor is the key procedure for a primary or secondary orbital deformity. After the unaffected side is mirrored onto the affected side using the patient's computer-tomography database, the defect can be reconstructed virtually. A measurement procedure that calculates the virtually reconstructed orbital surface data is available. These data are sent to a template machine that reproduces the physical surface. A flat titanium mesh can then be adjusted preoperatively to the spatial configuration of the anatomical structures. This procedure offers optimal anatomical reconstruction of the orbital floor, especially when the deep orbital cone is affected.     

Improving the Diagnostic Criteria for Primary Liver Graft Nonfunction in Adults Utilizing Standard and Transportable Laboratory Parameters: An Outcome‐Based Analysis

Current diagnostic criteria for primary nonfunction (PNF) of liver grafts are based on clinical experience rather than statistical methods. A retrospective, single‐center study was conducted of all adults (n = 1286) who underwent primary liver transplant (LT) 2000–2008 in our center. Laboratory variables during the first post LT week were analyzed. Forty‐two patients (3.7%) had 2‐week graft failure. Transplant albumin, day‐1 aspartate aminotransferase (AST), day‐1 lactate, day‐3 bilirubin, day‐3 international normalized ratio (INR), and day‐7 AST were independently associated with PNF on multivariate logistic regression. PNF score =(0.000280*D1AST)+ (0.361*D1 Lactate)+(0.00884*D3 Bilirubin)+(0.940*D3 INR)+(0.00153*D7 AST)‐(0.0972*TxAlbumin)‐4.5503. Receiver operating curve analysis showed the model area under receiver operating curve (AUROC) of 0.912 (0.889–0.932) was superior to the current United Kingdom (UK) PNF criteria of 0.669 (0.634–0.704, p < 0.0001). When applied to a validation cohort (n = 386, 34.4% patients), the model had AUROC of 0.831 (0.789–0.867) compared to the UK early graft dysfunction criteria of 0.674 (0.624–0.721). The new model performed well after exclusion of patients with marginal grafts and when modified to include variables from the first three post‐LT days only (AUROC of 0.818, 0.776–0.856, p = 0.001). This model is superior to the current UK PNF criteria and is based on statistical methods. The model is also applicable to recipients of all types of grafts (marginal and nonmarginal).     

Prospective Validation of a New Priority Allocation Model for Liver Transplant Candidates: An Interim Analysis

Background

The system that controls the waiting list (WL) and organ allocation for liver transplantation (OLT) seeks to achieve 3 main goals: objectivity, low dropout risks and good post-OLT results. We sought to prospectively validate a priority allocation model that is believed to achieve objectivity without penalizing dropout risk and post-OLT results.

Methods

We evaluated a study group of 272 patients enrolled in 2006-2007. WL candidates were divided into 2 categories: cirrhotic patients classified according to Model for End-Stage Liver Disease (MELD) score (MELD list and patients with hepatocellular carcinoma (HCC) organized according to a specific score (non-MELD list). The allocation algorithm for donor-recipient match assigned an optimal graft to the first MELD candidate with a MELD score of ≥20; a suboptimal graft, to the first non-MELD patient. A respective control group of 327 patients transplanted from 2003-2006 was characterized by a unique WL with a free allocation policy. We performed an interim analysis of this prospectively controlled study.

Results

Although the study group showed a lower percentage of OLT (P < .05) than the control group (37% vs 45%), it selected patients for OLT based on a higher MELD score (P < .05), thus obtaining similar dropout, post-OLT survivals, and intention-to-treat (ITT) survival probabilities as the controls. Among MELD patients, we observed a significantly reduced dropout and better ITT survival profiles than those of the control group (P = .02), whereas the similar results were delivered among non-MELD patients (P > .05). Among patients with a MELD score of ≥20, the prevalences of suboptimal grafts (0% vs 48%) and of early graft losses (0% vs 21%) were lower in the study than in the control group (P < .05).

Conclusions

We prospectively validated a priority allocation model based on objective criteria that achieved high ITT survival rates.