Tolerability and pharmacokinetics of the nitrone NXY-059 in patients with acute stroke

BACKGROUND AND PURPOSE

Increased free radical formation contributes to the damage caused to the brain by acute ischemia. NXY-059 is a nitrone-based free radical trapping agent in development for acute stroke. NXY-059 has neuroprotective efficacy when given 5 hours after onset of transient focal ischemia in the rat.

METHODS

This was a randomized, double-blind, placebo-controlled, parallel group, multicenter study that evaluated the safety and tolerability of 2 NXY-059 dosing regimens compared with placebo within 24 hours of acute stroke. NXY-059 was administered as either 250 mg over 1 hour followed by 85 mg/h for 71 hours or 500 mg over 1 hour followed by 170 mg/h for 71 hours; plasma concentrations were monitored. Neurological and functional outcomes were recorded up to 30 days.

RESULTS

One hundred fifty patients were recruited, of whom 147 received study treatments and completed assessments (50 placebo, 48 lower-dose NXY-059, 49 higher-dose NXY-059). Mean (+/-SD) age was 68 (+/-10) years, and baseline National Institutes of Health Stroke Scale score was 7.9 (+/-6.2). Serious adverse events occurred in 16%, 23%, and 16% of patients, respectively, with deaths in 0%, 10%, and 4%, largely following the proportions with primary intracerebral hemorrhage (6%, 16%, and 8%). Hyperglycemia, headache, and fever were common but not related to treatment. The mean unbound steady state NXY-059 plasma concentrations were 25 and 45 micromol/L, respectively. Population pharmacokinetic analysis estimated clearance to be 4.6 L/h.

CONCLUSIONS

NXY-059 was well tolerated in patients with an acute stroke. The testing of higher doses in future trials may be justified.

Biliary complications in living related liver transplantation

BACKGROUND

Biliary tract reconstruction has long been considered the Achilles' heel of liver transplantation as biliary complications can increase morbidity and mortality especially in partial liver graft transplantation.

METHODS

Thirty-four living related liver transplants were performed at Chang Gung Memorial Hospital in Kaohsiung for 33 children and 1 adolescent during a 5.5-year period. All potential donors underwent a detailed preoperative imaging study of the vascular and biliary anatomy, including three-dimensional helical computed tomographic cholangiography (n = 20), magnetic resonance cholangiography (n = 14), and intra-operative cholangiography (n = 31) before graft retrieval. All hepatic artery anastomoses were performed in the standard microsurgery fashion and their patency was confirmed intra-operatively using Doppler ultrasound.

RESULTS

The biliary complication rate was 8.8% (3/34), including multiple intrahepatic biliary stenosis of unknown origin (n = 1), bile leakage from the Roux-en-Y loop (n = 1), and a missed biliary radicle (n = 1) which were treated via interventional radiological and surgical procedures. The overall graft and patient survival rates were 100%.

CONCLUSION

The biliary complication rate in this series was low compared to those of other experienced centers. Complete study of the variations of intrahepatic duct ramification pre-and-intra-operatively provided adequate information on the appropriate transection plane. Furthermore, intra-operative Doppler ultrasound verification of vessel patency helps prevent vascular complications, which has been identified as a cause of biliary complications.

Outflow tract reconstruction in living donor liver transplantation

BACKGROUND

Hepatic venous reconstruction is critical in living donor liver transplantation because outflow obstruction may lead to graft dysfunction or loss. We describe our experience and analyze outcomes with a technique of creating a single outflow tract using venoplasties of the graft and recipient hepatic veins.

PATIENTS AND METHODS

A retrospective study was done on 38 consecutive living donor liver transplants performed from June 1994 to March 2000. The grafts included 36 left-side grafts and 2 right-side grafts. Nine grafts had multiple hepatic veins and required a venoplasty of two or three hepatic veins to create a single outflow orifice. Triple recipient hepatic venoplasty was performed in 32 patients, double venoplasty in 5 and none in 1.

RESULTS

There were four cases of outflow obstruction, three occurring in patients with a double recipient venoplasty. Two of the problems were remedied intraoperatively by adjusting the position of the graft although two were structural in nature and required the insertion of expandable metallic vascular stents. All donors and recipients with their original grafts are alive at a mean follow-up period of 27 months.

CONCLUSION

A triple recipient venoplasty with a matching venoplasty of multiple graft hepatic veins to create a single wide outflow orifice is recommended in living donor liver transplantation using left side grafts.

Aspiration in transtracheal oxygen insufflation with different insufflation flow rates during cardiopulmonary resuscitation in dogs

We investigated whether transtracheal insufflation of oxygen with different insufflation flow rates protects against aspiration of gastric contents during cardiopulmonary resuscitation (CPR). Its ventilation and oxygenation effects were also evaluated. Cardiac arrest was induced in anesthetized and paralyzed 18 mongrel dogs. Chest compression using an automatic thumper was performed while the dogs randomly received no mechanical ventilation (Group I, n = 6) or were transtracheally insufflated with 4 L/min oxygen (Group II, n = 6) or 10 L/min oxygen (Group III, n = 6). Blood samples were drawn every 5 min for 20 min for blood gas analysis. the mouths of the dogs were then filled with 70 mL mixed barium, and 10 min after chest compression, chest radiographs were taken to evaluate the incidence of pulmonary aspiration. Results showed that pulmonary aspiration occurred in all dogs of Group I and three of the six dogs in Group II, whereas dogs in Group III were free from pulmonary aspiration. Both transtracheal oxygen insufflation groups maintained oxygen saturation significantly better than Group I, but mild hypercapnia was observed in all groups after 20 min of CPR. We conclude that transtracheal oxygen insufflation, but not chest compression alone, was able to maintain oxygenation for 20 min during CPR in dogs with cardiac arrest. Mild hypercapnia was noted in all groups. Chest compression alone caused pulmonary aspiration, whereas insufflation of 10 L O(2)/min provided better protection against pulmonary aspiration than that of 4 L O(2)/min.

The value of angiography in diagnosis of Meckel's diverticulum: case report

Meckel's diverticulum is the most common anomaly of the gastrointestinal tract and usually produces no symptoms, although the classic symptom is painless rectal bleeding in a child. Because most symptomatic diverticula in children contain ectopic gastric tissue, radionuclide imaging using a technetium 99m pertechnetate scan is considered to be the method of choice. However, a bleeding Meckel's diverticulum may not be detected by pertechnetate imaging despite the presence of ectopic gastric mucosa. When the scan is negative, visceral angiography is an alternative procedure for detecting Meckel's diverticulum. We encountered a case of pathology-proven Meckel's diverticulum whose angiography result was diagnostic, while upper gastrointestinal panendoscopy, colonofibroscopy, barium enema studies, and repeated radionuclide scans were all negative. We report on this case to emphasize the potential role for angiographic detection of Meckel's diverticulum.

International sharing of split liver grafts in Asia: initial experience

The donor shortage problem is particularly serious in Asia and has markedly limited progress in liver transplantation. The increasing demand has, in fact, made it necessary to resort to living donor liver transplantation in both pediatric and adult recipients. Nevertheless, expanding the use of split liver allografts is yet another option to increase the supply. This has a wide potential application on a regional level because most liver transplant programs are still small and may have limited resources in terms of being able to do two transplants in one sitting. The first experience of overseas sharing of split liver grafts in Asia took place in January 1999. The graft was from a 35-yr-old donor from Kaohsiung, Taiwan, who sustained irreversible brain damage in a vehicular accident and had optimal conditions for multiorgan donation. The liver was split ex vivo and the left lateral segment was given to a 3-yr-old girl with biliary atresia at the Chang Gung Memorial Hospital. The extended right lobe split graft was transported to Hong Kong and transplanted into a 51-yr-old male patient with end-stage hepatitis C cirrhosis who was then in a state of acute failure with hepatorenal syndrome. Graft function was excellent in both recipients and the patient from Taiwan was discharged without any complications. Unfortunately, the Hong Kong recipient developed a cerebrovascular accident and required a reoperation for bile leakage from the cut surface of the liver in the early postoperative period. He has made a steady recovery since then; graft function has remained good and his kidneys have recovered. Both patients are currently alive and well 11 months post-transplant. This initial experience of overseas sharing of split liver grafts in Asia demonstrates its feasibility. It has a potentially wide applicability and could lead to the establishment of a formal organ-sharing network in the region. Established competence and mutual trust among the participating liver transplant teams would be essential in perpetuating such a graft-multiplying strategy on an organized basis.

The significance of functioning gallbladder visualization on hepatobiliary scintigraphy in infants with persistent jaundice

The purpose of this study was to determine whether gallbladder visualization can help exclude biliary atresia in hepatobiliary scintigraphic studies of infants with persistent jaundice.

METHODS

One hundred fifty-two infants with persistent jaundice (49 patients with a final diagnosis of biliary atresia and 103 with biliary patency) were studied using both hepatobiliary scintigraphy and abdominal sonography. Food was withheld for 4 h before the examination, and the infants were fed nothing but glucose until 6 h after the initial injection of (99m)Tc-disofenin or until the gallbladder was seen. If the gallbladder was seen, the infants were fed milk, and imaging was continued to observe gallbladder contractility.

RESULTS

In none of the 49 patients with biliary atresia could the gallbladder be seen with hepatobiliary scintigraphy, but abdominal sonography revealed 9 normal-sized gallbladders. Of the 103 patients with biliary patency, hepatobiliary scintigraphy detected the gallbladder more frequently (74%, 76/103) than did abdominal sonography (63%, 65/103). All visualized gallbladders contracted after the infants were fed milk. If we include visualization of both the gallbladder and bowel radioactivity as criteria, the specificity of biliary atresia on hepatobiliary scintigraphy increases to 86% (89/103).

CONCLUSION

Gallbladders were usually visible on hepatobiliary scintigraphy of fasting patients with biliary patency. A functioning gallbladder, with or without visualization of bowel radioactivity, indicated biliary patency.

Aspiration in chest compression alone without mechanical ventilation in the head down position in dogs

BACKGROUND

Previous work by the authors has shown that chest compressions alone without mechanical ventilation during cardiopulmonary resuscitation in the natural supine position was associated with pulmonary aspiration in dogs. The purpose of this investigation was to test the hypothesis that a head down position may prevent aspiration during chest compressions alone and whether oxygenation can be improved by simply insufflation of oral oxygen 10 min after cardiac arrest.

METHODS

Cardiac arrest was induced in ten mongrel dogs which were anesthetized and paralysed. Eight underwent chest compressions alone in different head down positions using an automatic compressor at 9 kg compression force and 3 cm compression depth. The study was composed of two parts. Part 1 evaluated the effect of insufflation of 10 l/min O2, into the mouth of the dogs, 10 min after initiation of resuscitation, using chest compressions alone. Part 2 was designed to test our hypothesis that the head down position may protect the lungs from aspiration during chest compression alone. The mouths of the dogs were filled with mixed barium and the dogs underwent serial episodes of chest compressions, for 10 min each, in the 20 degree head down, 10 degree head down and the natural supine positions. Chest X-rays with antero-posterior and lateral views were taken to evaluate pulmonary aspiration. Two additional dogs underwent direct chest compression alone in the natural supine position and the time of chest compression was shortened to 5 min.

RESULTS

All dogs in the natural position showed evidence of pulmonary aspiration of barium, five or six of the dogs showed tracheal aspiration in the 10 degree head down position, while no any barium was visualized in the tracheo-broncheal trees of the dogs in the 20 degree head down position. Supplemental oxygen in the mouth improved the mean PaO2 from 67 +/- 26 to 160 +/- 97 mmHg during chest compressions alone.

CONCLUSION

Chest compression alone without mechanical ventilation in the supine position caused pulmonary aspiration in the unprotected airway in dogs. This complication could be prevented by adopting a 20 degree head down position. The 10 degree head down position seemed to reduce the severity of the pulmonary aspiration, but not enough to eliminate the danger altogether. Supplemental oxygen in the mouth can improve oxygenation in chest compressions alone.

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.

Treatment of complicated hepatolithiasis with intrahepatic biliary stricture by ductal dilatation and stenting: long-term results

A group of 190 cases of hepatolithiasis with postoperative residual stones located proximal to the stricture sites were managed with the aim of complete clearance of stones and relief of bile stasis to decrease the potential risk of recurrence. All procedures were performed through a T-tube track with gradual dilatation and stent placement through the stricture sites, creating a channel that allows cholangioscopy and electrohydraulic lithotripsy. Complete clearance of intrahepatic duct (IHD) stones was achieved in 88.4% of cases. Multiple sharply angulated IHD strictures in right-sided hepatolithiasis constituted a major cause of failure. Recurrent stone formation and repeated cholangitis, subsequent drainage, and liver resection are associated with high mortality rates particularly if there is late development of a cholangiocarcinoma. We concluded that postoperative ductal dilatation and stenting through the T-tube track combined with endoscopic electrohydraulic lithotripsy is effective and safe for managing complicated hepatolithiasis. Persistent irreversible aneurysmal dilatation of IHD and atrophic change of the affected hepatic lobe at follow-up were ominous signs of recurrence and cholangiocarcinoma development. Early drainage with stone extraction combined with surgical intervention can prevent subsequent morbidity and mortality.

Conformal radiation therapy for hepatoma with portal vein thrombosis

A 43-year-old male patient was diagnosed as having hepatocellular carcinoma with portal vein thrombosis and arterioportal shunts. Three-dimensional conformal radiation therapy (3DCRT) with high focal dose was given to the left portal venous area. Shrinkage of the tumour and thrombus, disappearance of the arterioportal shunts and restoration of the hepatopedal flow of the portal vein was noted 3 months after treatment. The patient received further transarterial embolisation and achieved successful tumour control. No serious complications were encountered. 3DCRT is technically feasible and effective to treat a small volume of liver tissue with a high dose of radiation in this advanced disease.

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.

Telomerase activity in rat liver allografts

BACKGROUND

Telomerase activity in grafts may be involved in the alteration of cellular senescence after transplantation or its relevant immunological events.

METHODS

At the age of 20 weeks, donor livers harvested from DA (RT1a) were orthotopically transplanted into PVG (RT1c) or LEW (RT1(1)) rats. Rats having undergone orthotopic liver transplantation (OLT; DA-PVG) naturally overcome rejection, whereas all OLT (DA-LEW) rats die from acute rejection within 14 days. Telomerase activity in liver allografts was measured at various intervals post OLT.

RESULTS

At day 7 when the most severe rejection episode was observed in OLT (DA-LEW) and OLT (DA-PVG), the telomerase activity was significantly higher than in syngeneic OLT (DA-DA) rats, in which no rejection occurred. Telomerase activity in tolerogenic OLT (DA-PVG) livers remained elevated for at least 2 months.

CONCLUSION

These results suggest that telomerase activity in allogeneic OLT livers may reflect regenerating hepatocytes or activation of lymphocytes and/or hematopoietic stem cells associated with rejection or tolerance.

Evaluation of the prognostic value of serum soluble CD 44 in patients with breast cancer

The outcome of breast carcinoma is usually determined by multiple factors. Aberrant expression of the cell adhesion molecule CD 44 has been claimed to be associated with poor prognosis in various human malignancies. This study was designed to investigate any correlation between the soluble adhesion molecule CD 44 and the clinicopathologic variables and to evaluate the possible prognostic significance of soluble CD 44. Venous blood samples were preoperatively collected from 100 patients with invasive breast carcinoma. The serum levels of different soluble CD 44 molecules (CD 44 standard form and CD 44 splice variant V6) were measured with an enzyme immunoassay method. The data of primary tumor status, age, estrogen receptor status, lymph node status, histologic grading, distant metastases status, TNM staging, S-phase fraction, and ploidy pattern were collected and evaluated simultaneously with the serum levels of soluble CD 44 st and CD 44 V6. Twenty healthy subjects were used as the control group. The serum levels of soluble CD 44 st showed no significant elevation in patient group. The mean value of soluble CD 44 V6 in patient group was 269.2 +/- 94.3 ng/ml and that of the control group was 179.5 +/- 50.7 ng/ml; the difference was significant (p < 0.01). In multivariate analysis, distant metastasis (p < 0.05) and TNM staging (p < 0.01) appeared as independent factors regarding the significant higher serum levels of soluble CD 44 V6. Based on our preliminary results, preoperative serum soluble CD 44 V6 is closely related to distant metastases and TNM staging. The possible role of soluble CD 44 V6 in the prognostic value of breast carcinoma deserves further elucidation and evaluation with long-term patient follow-up.