Minimal blood loss living donor hepatectomy

BACKGROUND

Donor hepatectomy with maximal safety while preserving graft viability is of principal concern in living donor liver transplantation. There are compelling reasons for avoiding blood transfusion, even with autologous blood, to avoid the potential risks it imposes on healthy donors. This study aims to describe the surgical technique and clinical outcomes of living donor hepatectomy with minimal blood loss requiring no blood transfusion.

METHODS

Donor hepatectomy was performed in 30 living donors according to a detailed preoperative imaging study of the vascular and biliary anatomy. Liver parenchymal transection was carried out with strict adherence to a meticulous surgical technique without vascular inflow occlusion to either side of the liver. Pre-, intra-, and postoperative data were gathered, and factors related to blood loss were analyzed retrospectively.

RESULTS

The intraoperative blood loss ranged from 20 to 300 ml with a mean of 72.0+/-58.9 ml (median, 55 ml), and neither homologous nor autologous blood transfusion was required in any of the donors intra- and postoperatively. All 30 donors were discharged with minimal complications, and remain well at a mean follow-up of 24 months after donation. Excellent graft viability was verified by the fact that all 30 recipients are alive and well with a few manageable complications. The actual graft and patient survival are both 100% at the time of writing.

CONCLUSIONS

Regardless of the extent of donor hepatectomy, blood loss can and should be kept to a minimum, and living donor hepatectomy without blood transfusion is a realistic objective.

Repeated hypotensive episodes due to hepatic outflow obstruction during liver transplantation in adult patients

We report two cases of unusual repeated hypotension, decreased cardiac output, decreased mixed venous oxygen saturation, decreased central venous pressure, pulmonary artery pressure, and pulmonary wedge pressure after the completion of all vascular anastamoses of liver transplantation. These unstable hemodynamics appear to reflect a clinically relevant picture of hypovolemia. However, the real cause was partial hepatic outflow obstruction. The obstruction was suspected because hypotension was alleviated by elevating the full-sized liver graft ventrally and to the left. Doppler ultrasound examination confirmed that the flow velocity of the hepatic vein outflow was insufficient when the liver fell to its resting position in the right hepatic fossa. An additional side-to-side cavo-caval anastomosis resolved the problem in one patient, whereas the other required not only the additional anastomosis, but also application of a tissue expander filled with 770 mL normal saline beneath the liver to eliminate the obstruction. We emphasize that obstruction of the hepatic outflow causes only temporal hypovolemia because of a decrease of venous return and that treatment of this complication should be surgical intervention to relieve the obstruction. Blind resuscitation with fluids will not solve the problem and, in fact, may result in fluid overload with subsequent complications.

Magnetic resonance of the hepatic veins with angular reconstruction: application in living-related liver transplantation

BACKGROUND

Preoperative mapping of the hepatic venous system of the partial liver graft is indispensable to the success of living-related liver transplantation. We assessed the accuracy of magnetic resonance (MR) venography with angular reconstruction in depicting the tributaries of the middle hepatic vein and left hepatic vein in the donors, which was essential in graft retrieval and venoplasty.

METHODS

Nineteen living-related liver transplantation donors underwent a pretransplantation survey, including sonography and MRI for hepatic venous evaluation. T1-weighted images were reconstructed manually, using the inferior vena cava as a fixed point for tilting to produce an oblique plane image where both the middle hepatic vein and left hepatic vein could be demonstrated draining into the inferior vena cava. The reconstructed images of the hepatic veins were compared with preoperative sonography, intraoperative sonography, and operative findings.

RESULTS

Preoperative sonography and MR findings correlated well with the operative findings in the major hepatic veins. The MR venography of the ramification of the hepatic veins has an accuracy of 93%, the sonography, 84%. Sonography is slightly inferior in the evaluation of the hepatic vein in segment 4 and the left superior hepatic vein, with an accuracy of 73% and 67%, respectively.

CONCLUSION

MR venography with angular reconstruction is accurate in depicting the complex distribution of the hepatic veins of the left liver, providing important information for decision making as to the cutting plane during graft retrieval and the method of venoplasty and anastomosis. Thus, unnecessary blood loss could be avoided and vascular complications could be prevented, as these conditions would be unacceptable for a healthy living donor. We propose that MR venography, a rapid and reliable technique, is an appropriate alternative examination or complementary modality to sonography in the pretransplantation evaluation of the living donor.

Aspiration and transtracheal jet ventilation with different pressures and depths of chest compression

OBJECTIVE

To evaluate aspiration prophylaxis during cardiopulmonary resuscitation (CPR) using transtracheal jet ventilation (TJV) with different pressure-depths of chest compression and chest compression alone without mechanical ventilation.

DESIGN

Prospective, animal study.

SETTING

Animal research laboratory, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Taiwan.

SUBJECTS

Mongrel dogs (n = 10) weighing 8 to 12 kg.

INTERVENTIONS

Eight mongrel dogs were anesthetized, paralyzed, and ventilated transtracheally with a jet ventilator at frequencies varied from 600 to 10 cycles/min. The airway pressures below and above the jetting port were measured. The mouth of the dog was filled with barium and chest radiographs were taken 10 mins after chest compression with 20-pound pressure and 5-cm depth in group 1 and 10-pound pressure and 3-cm depth in group 2 at each different jet frequency. Two additional dogs underwent the same procedures but received only chest compression without TJV.

MEASUREMENTS AND MAIN RESULTS

Pulmonary aspiration was not noted in the chest radiographs from either group. The airway pressure changes between groups were not significantly affected by difference in pressures and depths of chest compression at the same jetting frequency. However, pulmonary aspiration occurred in the two dogs that received chest compression alone without TJV.

CONCLUSIONS

Application of TJV during chest compression with different pressures and depths caused no pulmonary aspiration in dogs at frequencies between 600 and 10 cycles/min. The protection against aspiration disappeared if the dogs received only chest compression without TJV. The mechanism of preventing pulmonary aspiration in TJV is thought to be due to forceful unidirectional gas outflow through the larynx and higher airway pressure in the carina than in the upper airway. The airway pressures were not affected by different chest compression pressures and depths because the larynx stayed open during TJV and the air outflow could freely move out without increasing the pressure in the airway.

Post-transplant changes of segment 4 after living related liver transplantation

The purpose of this study was to evaluate the outcome of the medial segment of the graft after living related liver transplantation (LRLT). Of the 12 pediatric recipients who underwent LRLT, 2 received whole left liver graft, 1 left lateral segment graft, and 9 extended left lateral segment grafts. The hepatic veins of the donor were reviewed and the volume of the medial segment and left lateral liver was measured before and 6 months after liver transplantation. The flow velocity and direction of the portal vein in the medial segment graft was also evaluated by Doppler ultrasound. The grafted livers of all recipients showed a substantial increase in volume of 9-120% 6 months after LRLT. For the left lateral segment, an increase in volume was found in all cases ranging from 21 to 245%. For the medial segment, volume increases of 5-48% were found in seven cases with normal hepatopetal flow detected inside the segment 4 intrahepatic portal vein. In four cases, the partial medial segment graft of the extended left lateral liver graft decreased in volume from 33 to 69%. Among these four cases, slow flow (n = 2) and hepatofugal flow (n = 1) were also detected in the intrahepatic portal vein of the medial segment. Mapping of the tributary of the hepatic veins of the graft revealed inadequate venous drainage of the partial segment 4 graft, which may be considered as the cause of the atrophic change of the partial segment 4 graft. In conclusion, different regenerative rates between the left lateral segment and the medial segment were noted, with a greater rate in the left lateral segment. The venous drainage of the medial segment is of primary concern in the determination of the outcome of the regeneration. Atrophic change occurs when inadequate hepatic venous drainage is encountered. Therefore, if an extended left lateral liver graft is required, the corresponding draining veins of the partial medial segment must be preserved. Otherwise, whole left liver or left lateral segment graft would be a better choice.

Intraoperative Doppler ultrasound in liver transplantation

The purpose of this study was to determine the utility of intraoperative Doppler ultrasound for the diagnosis and reduction of the vascular complications in liver transplantation. This study included 19 pediatric and 5 adult patients. In the pediatric group, 12 patients received living related liver transplantation (LRLT), two splitting liver transplantation (SLT), three reduced-size liver transplantation (RLT) and two full-size pediatric liver transplants (FPLT). The hemodynamics and waveform of the hepatic vein, portal vein and hepatic artery were evaluated by intraoperative Doppler ultrasound (US) after reperfusion of the graft. Unsatisfactory hemodynamics was identified in nine cases, including decrease hepatic venous flow (6-9 cm/s) with non-pulsative flat waveform (adults, n = 2 and LRLT, n = 2); portal vein thrombosis (LRLT, n = 1); decrease portal flow (8 mL/min/kg) (LRLT, n = 1); occlusion of the portal vein (SLT, n = 1); poor arterial flow with dampened artery waveform (FPLT, n = 2). These abnormalities were all successfully re-reconstructed by surgical procedures and achieved a graft survival rate of 100%. Two late vascular complications including hepatic venous thrombosis and recurrent portal vein stenosis with splenorenal shunt were discovered 1 month later. They were treated effectively by surgical thrombolectomy and percutaneous balloon dilatation and metallic coils embolization respectively. Three patients died of non-vascular complications and all patients who underwent LRLT survived with a resultant 87.5% overall survival rate. In conclusion, intraoperative Doppler US is efficient in detecting abnormal hepatic hemodynamics, which permits early intervention and hence a better prognosis for the patients. Re-reconstructive procedures were monitored closely under Doppler US guidance until proper flow and wave-form were established. This reduces post-transplant vascular complications and thereby eliminates the likelihood of a lethal complication that might call for re-transplantation.

A survey of antipsychotic treatment for schizophrenia in Hong Kong

OBJECTIVE

To obtain information on prescription pattern of antipsychotic drugs for schizophrenic in-patients treated in public hospitals in Hong Kong. Four main areas of antipsychotic treatment are reported in this paper: (1) doses of antipsychotic drugs, (2) the practice of giving multiple antipsychotic agents simultaneously, (3) use of antipsychotics in divided daily doses and (4) co-administration of antipsychotic and antiparkinson drugs.

METHODS

A cross-sectional survey of prescriptions of antipsychotic medication for a representative sample of 957 schizophrenic in-patients was conducted on a randomly chosen census day. Questionnaire items included basic demographic and clinical data, as well as inventory for all medications received by patients on census day.

RESULTS

The mean antipsychotic dose was 854 +/- 759 (median: 600; range) 0-4450) mg CPZeq. Over two-third of the patients were given more than drug concurrently while less than 20% received the medication in multiple divided doses. Antiparkinson drugs were prescribed with antipsychotic medication in 69.61%, of the subjects. There were few differences between acute and chronic patients with respect to their respective prescription patterns.

CONCLUSIONS

Antipsychotic treatment of schizophrenic inpatients in Hong Kong is largely in accord with international standards. Problematic areas identified for closer scrutiny include the concurrent use of more than one antipsychotic drug for both acute and chronic patients, and the higher than recommended doses for antipsychotic drugs and frequent use of antiparkinson medication for chronic patients. Dissemination of these results, accompanied by continuing medical education about psychopharmacology, are planned to further improve the quality of treatment for schizophrenic patients.

Histopathology of the liver in pediatric patients following transplantation

Recognition of rejection and other hepatic complications by needle biopsy plays a significant role in the management of liver allograft recipients. In this report, 22 pediatric patients (below 18 years old) were selected from the 37 liver transplants. Seven of the 22 cases have an uneventful posttransplant course. The most common cause of allograft injury in these patients appeared to be acute cellular rejection. It occurred in 7 (31.8%) of the 22 cases and was the primary process in 8 of the 25 episodes of liver dysfunction. Other etiologies, such as opportunistic viral infection (3 cases), biliary obstruction (2 cases), preservation injury (1 case), and vascular obstruction (1 case) were less common. Acute graft rejection causing liver dysfunction was associated with a mixed portal inflammation, destruction of the interlobular bile ducts, and varied degree of venous endotheliitis, followed by centrilobular hepatocyte necrosis. Chronic rejection was not seen in our pediatric cases. Cold ischemic injury causing transient graft dysfunction as seen in one of our patients demonstrated focal, limited areas of hepatocyte necrosis, mild centrilobular hepatocyte ballooning, and cholestasis without evidence of bile duct damage. More severe ischemic injury resulted from vascular complication causing diffuse hepatocyte necrosis was seen in one patient with hepatic vein thrombosis. The histologic patterns observed were not pathognomic; however, liver biopsies were helpful in suggesting the probable cause of liver dysfunction and in predicting subsequent allograft recovery when used in conjunction with clinical information, radiologic, and other laboratory tests.

Imaging in pediatric liver transplantation

In liver transplantation, the role of the imaging study in the evaluation of transplant candidacy is to define the conditions in which transplantation is contraindicated and to identify anatomic variations that may alter the surgical approach. Among pediatric recipients, the largest numbers of patients were suffering from biliary atresia, and metabolic diseases. Acquired and congenital vascular anomalies are usually associated with biliary atresia which may be hazardous to liver transplantation requiring a modification of standard surgical procedure. Therefore, confirmation of the patency of the vascular structure is the most essential prerequisite especially in living related liver transplantation. From June 17, 1994 to November 30, 1996, eleven living related liver transplantations were performed at Chang Gung Memorial Hospital, Kaohsiung Medical Center. The left liver or the left lateral segment of the liver was used as the graft. It is necessary to keep patency of the inflow and outflow of hepatic vessels and biliary trees of both donor and recipient. Both resected and remnant livers have to function well postoperatively. In order to achieve parenchyma dissection with minimal hepatic damage, various anatomical variations of the liver size, portal vein, hepatic veins and bile duct of the donor cannot be ignored. Therefore, the precise preoperative anatomical evaluation of the donor using various imaging modalities is mandatory for the safe partial liver transplantation. Ultrasound, computed tomography, magnetic resonance image and three dimensional computed tomographic cholangiography are the method of choice in demonstrating the anatomical structures. After the complex anatomical factors can be well evaluated we can assess the appropriateness and feasibility of the procedure that may correct problems during or after transplantation. Finally, noninvasive and safe examination procedures are our outmost concern and policy in doing this survey.

Community psychiatry in Hong Kong

Community psychiatry is well developed in many western countries. However, this psychiatric subspecialty has only recently been officially recognized and established in Hong Kong. This article describes the development and current scope of services. It illustrates how local psychiatrists have met the challenge of adopting a western service model to suit the local Chinese population, with its different socio-cultural value system.

Osteopontin N-terminal domain contains a cryptic adhesive sequence recognized by alpha9beta1 integrin

Osteopontin is an adhesive glycoprotein implicated in numerous diseases associated with inflammation and remodeling. There are several structural domains in osteopontin that are of particular interest. The RGD motif is a cell attachment sequence shown to be critical for cell adhesion through alphav-containing integrins. In close proximity to the RGD domain is the thrombin cleavage site. Previous observations suggest that thrombin cleavage of osteopontin occurs in vivo and may be physiologically important. To study the functional significance of osteopontin cleavage by thrombin, we made glutathione S-transferase-osteopontin fusion proteins. These proteins contain either the N- or C-terminal domains expected to be formed following thrombin cleavage at the Arg169-Ser170 peptide bond. We compared these osteopontin fragments with native osteopontin in their ability to support adhesion of several different cell lines and identified the receptors mediating these interactions. Our data show that the N-terminal osteopontin fragment, which contains the RGD domain, supports adhesion of a melanoma cell line that is unable to bind native osteopontin. This suggests that osteopontin adhesive interactions may be regulated by thrombin cleavage. We also demonstrate that osteopontin contains a cryptic binding activity, which can be recognized by a novel osteopontin receptor. This receptor has been identified as the alpha9beta1 integrin.