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Dive into the research topics where Steven D. Colquhoun is active.

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Featured researches published by Steven D. Colquhoun.


Annals of Surgery | 1992

Biliary strictures complicating liver transplantation. Incidence, pathogenesis, management, and outcome.

nd J O Colonna; Abraham Shaked; Antoinette S. Gomes; Steven D. Colquhoun; O Jurim; S. V. McDiarmid; J M Millis; Leonard I. Goldstein; Ronald W. Busuttil

Six hundred sixty-six patients received 792 liver transplants between February 1, 1984 and September 30, 1991. Biliary reconstruction was by choledochocholedochostomy (CDCD) with T-tube (n = 509) or Roux-en-Y choledochojejunostomy (CDJ) (n = 283). Twenty-five patients (4%) developed biliary strictures. Anastomotic strictures were more common after CDJ (n = 10, 3.5%) than for CDCD (n = 3, 0.6%). Intrahepatic strictures developed in 12 patients. Six patients had occult hepatic artery thrombosis (HAT). The other six patients received grafts in which cold ischemia time exceeded 12 hours. Anastomotic strictures were successfully managed by percutaneous dilation (PD) in five patients (n = 10), operation in three (n = 6), with retransplantation required in two patients. Intrahepatic strictures were managed by PD in seven, retransplantation in one, and expectantly in four patients. Of 25 patients, 19 (76%) are alive with good graft function. In three of six deaths, the biliary stricture was a significant factor to the development of sepsis and allograft failure. The authors conclude that (1) anastomotic strictures are rare after LT; (2) the development of biliary strictures may signify occult HAT; (3) PD is effective for most strictures; and (4) extended cold graft ischemia (less than 12 hours) may be injurious to the biliary epithelium, resulting in intrahepatic stricture formation.


Transplantation | 1997

In situ splitting of the cadaveric liver for transplantation

John A. Goss; H. Yersiz; Christopher R. Shackleton; P Seu; Craig V. Smith; Jay S. Markowitz; Douglas G. Farmer; Rafik M. Ghobrial; James F. Markmann; Walid S. Arnaout; David K. Imagawa; Steven D. Colquhoun; Fraiman Mh; S. V. McDiarmid; Ronald W. Busuttil

BACKGROUND The shortage of cadaveric donor livers is the rate-limiting step in clinical liver transplantation. Split liver transplantation provides a means to expand the cadaveric donor pool. However, this concept has not reached its full potential because of inferior patient and graft survival and high complication rates when traditional ex vivo split techniques are used. Therefore we sought to evaluate the safety, applicability, and effectiveness of a new technique for split liver transplantation. METHODS This study consists of 15 in situ split liver procurements, which resulted in 28 liver transplants. In situ splitting of selected livers from hemodynamically stable cadaveric donors was performed at the donor hospital without any additional work-up or equipment being needed. In situ liver splitting is accomplished in a manner identical to the living-donor procurement. This technique for liver splitting results in a left lateral segment graft (segments 2 and 3) and a right trisegmental graft (segments 1 and 4-8). This procedure required the use of the donor hospital operating room for an additional 1.5-2.5 hr and did not interfere with the procurement of 30 kidneys, 12 hearts, 7 lungs, and 9 pancreata from these same donors. RESULTS The 6-month and 1-year actuarial patient survival rates were 92% and 92%, respectively, while the 6-month and 1-year actuarial graft survival rates were 86% and 86%, respectively. The 6-month and 1-year actuarial patient survival rate of patients who received a left lateral segment graft was 100% and 100%, respectively, while those who received a right trisegmental graft had 6-month and 1-year rates of 86% and 86%, respectively. The actuarial death-censored graft survival rates at 6 months and 1 year were 80% and 80%, respectively, for the left lateral segment grafts, and 93% and 93%, respectively, for the right trisegmental grafts. Alograft and patient survival was independent of United Network for Organ Sharing status at the time of liver transplantation. No patient developed a biliary stricture, required re-exploration for intra-abdominal hemorrhage, or suffered from portal vein, hepatic vein, or hepatic artery thrombosis CONCLUSIONS In situ split liver transplantation can be accomplished without complications and provides results that are superior to those obtained previously with ex vivo methods. It abolishes ex vivo benching and prolonged ischemia times and provides two optimal grafts with hemostasis accomplished. This technique decreases pediatric waiting time and allows adult recipients to receive right-sided grafts safely. In situ splitting is the method of choice for expanding the cadaveric liver donor pool.


Annals of Surgery | 1999

Orthotopic liver transplantation for hepatitis C : Outcome, effect of immunosuppression, and causes of retransplantation during an 8-year single-center experience

Rafik M. Ghobrial; Douglas G. Farmer; Angeles Baquerizo; Steven D. Colquhoun; Hugo R. Rosen; Hasan Yersiz; James F. Markmann; Kenneth E. Drazan; Curtis Holt; David K. Imagawa; Leonard I. Goldstein; Paul Martin; Ronald W. Busuttil

OBJECTIVE To determine the outcome of orthotopic liver transplantation (OLT) for end-stage liver disease caused by hepatitis C virus (HCV). SUMMARY BACKGROUND DATA HCV has become the leading cause of cirrhosis and hepatic failure leading to OLT. Recurrent HCV after OLT is associated with significant complications and may lead to graft loss that requires retransplantation (re-OLT). The authors studied the outcome of transplantation for HCV, the effect of primary immunotherapy, and causes of retransplantation. METHODS The authors conducted a retrospective review of their experience during an 8-year period (1990-1997), during which 374 patients underwent transplants for HCV (298 [79.6%] received one OLT; 76 [20.4%] required re-OLT). Median follow-up was 2 years (range 0 to 8.3). Immunosuppression was based on cyclosporine in 190 patients and tacrolimus in 132 patients. In a third group of patients, therapy was switched from cyclosporine to tacrolimus or from tacrolimus to cyclosporine (cyclosporine/tacrolimus group). RESULTS Overall, 1-, 2-, and 5-year actuarial patient survival rates were 86%, 82%, and 76%, respectively. The 2-year patient survival rate was 81 % in the cyclosporine group, 85% in the tacrolimus group, and 82% in the cyclosporine/tacrolimus group. In patients receiving one OLT, overall 1-, 2-, and 5-year patient survival rates were 85%, 81%, and 75%, respectively. The 2-year patient survival rate was 79% in the cyclosporine group, 84% in the tacrolimus group, and 80% in the cyclosporine/tacrolimus group. The overall graft survival rates were 70%, 65%, and 60% at 1, 2, and 5 years, respectively. The graft survival rate at 2 years was similar under cyclosporine (68.5%), tacrolimus (64%), or cyclosporine/tacrolimus (60%) therapy. Re-OLT was required in 42 (11.2%) patients for graft dysfunction in the initial 30 days after OLT. Other causes for re-OLT included hepatic artery thrombosis in 10 (2.6%), chronic rejection in 8 (2.1%), and recurrent HCV in 13 (3.4%) patients. The overall survival rates after re-OLT were 63% and 58% at 1 and 2 years. The 1-year survival rate after re-OLT was 61 % for graft dysfunction, 50% for chronic rejection, 60% for hepatic artery thrombosis, and 60% for recurrent HCV. At re-OLT, 85.3% of the patients were critically ill (United Network for Organ Sharing [UNOS] status 1); only 14.7% of the patients were UNOS status 2 and 3. In re-OLT for chronic rejection and recurrent HCV, the 1-year survival rate of UNOS 1 patients was 38.4%, compared with 87.5% for UNOS 2 and 3 patients. In patients requiring re-OLT, there was no difference in the 1-year patient survival rate after re-OLT when cyclosporine (60%), tacrolimus (63%), or cyclosporine/tacrolimus (56%) was used for primary therapy. With cyclosporine, three patients (1.5%) required re-OLT for chronic rejection versus one patient (0.7%) with tacrolimus. Re-OLT for recurrent HCV was required in four (3%) and seven (3.6%) patients with tacrolimus and cyclosporine therapy, respectively. CONCLUSIONS Orthotopic liver transplantation for HCV is performed with excellent results. There are no distinct advantages to the use of cyclosporine versus tacrolimus immunosuppression when patient and graft survival are considered. Re-OLT is an important option in the treatment of recurrent HCV and should be performed early in the course of recurrent disease. Survival after re-OLT is not distinctively affected by cyclosporine or tacrolimus primary immunotherapy. The incidence of re-OLT for recurrent HCV or chronic rejection is low after either tacrolimus or cyclosporine therapy.


Annals of Surgery | 1994

One thousand liver transplants. The lessons learned.

Ronald W. Busuttil; Abraham Shaked; J M Millis; O Jurim; Steven D. Colquhoun; Christopher R. Shackleton; B J Nuesse; M Csete; Leonard I. Goldstein; S. V. McDiarmid

ObjectiveTo evaluate the first 1000 liver transplants performed at UCLA Medical Center to determine factors responsible for improved results. Summary Background DataSummary Background Data transplant has evolved impressively since the first case was performed in 1963. The 1980s have highlighted this progress with the development of better organ preservation, standardization of operative procedure, improved immunosuppressive agents, and better understanding of patient selection. MethodsThe first 100 consecutive liver transplants (group 1) performed from February 1984 through October 1986 were compared with the last 200 (group 2) performed between September 1991 and June 1992. An analysis was made of donor use; changes in patient candidacy; patient care variables; morbidity and mortality; survival data; and hospital resource use. ResultsResults group 1,31 % of donors were refused because of medical unsuitability compared with 4% in group 2 (p <0.0001). in group 1, alcoholic patients comprised 1% of liver transplant candidates compared with 20% group 2 (p < 0.0001). High-risk patients (United Network for Organ Sharing criteria 4) only comprised 11 % of patients in group 1 compared with 37% in group 2 (p < 0.0001). Operative time (7.6 hours compared with 5.4 hours), packed cell replacement (17 units compared with 9.5 units), intensive care unit stay (10 days compared with 5 days), and hospital stay (50 days compared with 31 days) were all significantly improved (p < 0.05). In group 1, the 1-year survival rate was 73% and improved to 88% in group 2 (p < 0.0001). ConclusionsConclusions unfavorable donor characteristics (obesity, cause of death, age, hypotension), most organs function well and should not be refused based on history alone. The older and high-risk patient (renal failure, ventilator dependence, portal vein pathology, and so on) is routinely transplanted with good success. Despite liberalization of both donor and recipient criteria patient survival after liver transplant is improved, use of hospital resourances is maximized, and cost reduction is achieved.


Journal of Gastroenterology and Hepatology | 2006

Living donor liver transplantation : Histological abnormalities found on liver biopsies of apparently healthy potential donors

Tram T. Tran; Chanikarn Changsri; Christopher R. Shackleton; Fred Poordad; Nicholas N. Nissen; Steven D. Colquhoun; Stephen A. Geller; John M. Vierling; Paul Martin

Objective:  With the continued shortage of deceased donor grafts, living donor liver transplantation has become an option for adult liver transplant candidates. In the non‐transplant setting, liver biopsy is typically carried out to evaluate clinical or biochemical hepatic dysfunction. In living donor liver transplantation, assessment of histological abnormalities that are undetectable by serological, biochemical and radiological methods might play an important role in donor and recipient outcome.


Transplantation | 1999

Intracranial pressure during liver transplantation for fulminant hepatic failure.

Olivier Detry; N. Arkadopoulos; Paul Ting; Elaine Kahaku; Jody E. Margulies; Walid S. Arnaout; Steven D. Colquhoun; Jacek Rozga; Achilles A. Demetriou

During orthotopic liver transplantation (OLT) for fulminant hepatic failure (FHF), some patients develop cerebral injury secondary to intracranial hypertension. We monitored intracranial pressure (ICP) and cerebral perfusion pressure (CPP) before and during OLT in 12 FHF patients undergoing transplantation. All four patients who had normal ICP preoperatively maintained normal ICP/CPP throughout OLT. During OLT, four of the eight patients with pretransplant intracranial hypertension had six episodes of ICP increase. These episodes of intracranial hypertension occurred during failing liver dissection (n=3) and graft reperfusion (n=3). At the end of the anhepatic phase, the ICP was lower than the preoperative ICP in all patients, and was below 15 mmHg in all but one patient. These data suggest that in FHF patients who develop intracranial hypertension before OLT, dissection of the native liver and graft reperfusion are associated with a risk of brain injury resulting from intracranial hypertension and cerebral hypoperfusion.


Annals of Surgery | 1993

Celiac compression syndrome and liver transplantation.

O Jurim; Abraham Shaked; K Kiai; J M Millis; Steven D. Colquhoun; Ronald W. Busuttil

ObjectiveThe authors assessed the prevalence and clinical significance of the celiac compression syndrome in liver transplantation patients. Summary Background DataCompression of the celiac axis by the median arcuate ligament of the diaphragm, causes a decrease in celiac artery blood flow which may lead to hepatic artery thrombosis in patients undergoing orthotopic liver transplantation. MethodsFrom July 1991 to July 1992, 17 (10%) cases of celiac compression syndrome were identified among 164 consecutive adult patients who underwent liver transplantation. The diagnosis was confirmed by blood flow recording demonstrating a typical pattern of accentuated decrease in celiac blood flow during expiration. ResultsSurgical transaction of the median arcuate ligament resulted in normalization of the hepatic artery blood flow. In two cases (11.7%), an interposition iliac graft from the recipient supra-celiac aorta was used for the arterial reconstruction. During the follow-up period of up to 15 months, there was no incidence of hepatic artery thrombosis. ConclusionsThe clinical significance of the celiac compression syndrome is evident in liver transplantation in which the collateral circulation to the liver is compromised and the celiac artery remains the only source of arterial blood. It is imperative to Identify and remove the obstruction of the celiac axis to prevent severe complications and potential graft loss.


American Journal of Surgery | 1997

The impact of microsurgical hepatic arterial reconstruction on the outcome of liver transplantation for congenital biliary atresia

Christopher R. Shackleton; John A. Goss; Kim Swenson; Steven D. Colquhoun; Philip Seu; Milan Kinkhabwala; Stephen Rudich; Jay S. Markowitz; Suzanne V. McDiarmid; Ronald W. Busuttil

BACKGROUND Hepatic artery thrombosis (HAT) after liver transplantation for biliary atresia (BA) is a serious complication that most often leads to retransplantation (re-OLT). The purpose of the present study was: (1) to identify risk factors associated with HAT and (2) to analyze the impact of recently introduced microsurgical hepatic arterial reconstruction (MHR) on the incidence of HAT, subsequent need for re-OLT, and patient survival. METHODS A retrospective review of 194 patients transplanted for BA was performed. One hundred and sixty-six patients (group 1) underwent conventional arterial reconstruction and 28 (group 2) had MHR. RESULTS Actuarial survival for patients with HAT was significantly worse than for patients without HAT at 1, 2, and 5 years (71%, 61%, and 57% versus 85%, 85%, and 85%, P = 0.0007). Stepwise logistic regression analysis revealed that the risk of HAT correlated best with the type of arterial reconstruction (P = 0.007) followed by pretransplant bilirubin concentration (P = 0.04) and the number of acute rejection episodes (P = 0.03). In group 1, 32 patients developed HAT (19%), and of these, 18 underwent re-OLT for HAT. No patient in group 2 developed HAT (P = 0.006 versus group 1). One-year actuarial patient survival was 81% in group 1 and 100% in group 2 (P = 0.02). CONCLUSIONS In OLT for BA, (1) the predominant risk factor for HAT is the technique of arterial reconstruction, and (2) MHR markedly reduces the incidence of HAT and the need for re-OLT while improving patient survival.


The Annals of Thoracic Surgery | 1991

Role of percutaneous fine-needle aspiration biopsy in suspected intrathoracic malignancy

Steven D. Colquhoun; Dorothy L. Rosenthal; Donald L. Morton

Percutaneous fine-needle aspiration (PFNA) biopsy is an accepted technique for the diagnosis of suspected intrathoracic malignancy, but the appropriate indications for its use have not been clearly defined. To help establish guidelines, we performed a retrospective analysis of 188 patients who underwent PFNA biopsy for suspected intrathoracic malignancy. Biopsy led to a diagnosis in 72% (135/188) of the patients, but in 27% (50/188) samples were inadequate for cytological diagnosis, and in 2% (3/188) samples were adequate but failed to yield a diagnosis. Fifty-three patients underwent surgical intervention, thus allowing histological confirmation of the cytological diagnosis. In patients with a diagnosis from PFNA biopsy, operation confirmed malignancy in 97% (37/38) and a specific cell type in 79% (30/38). In patients without a diagnosis after biopsy, a malignancy was found in 73% (11/15) at the time of operation. This suggests a high rate of accuracy when PFNA biopsy provides a diagnosis. However, it also illustrates that a substantial percentage of PFNA biopsy attempts fail to yield a diagnosis in patients ultimately found to have malignancies. This implies that PFNA biopsy might best be reserved for patients who are not surgical candidates.


Liver Transplantation | 2001

Transmission of hepatitis B infection from hepatitis B core antibody–positive liver allografts is prevented by lamivudine therapy

Andy S. Yu; John M. Vierling; Steven D. Colquhoun; Walid S. Arnaout; Chuek Kee Chan; Elham Khanafshar; Stephen A. Geller; W. Stephen Nichols; Tse‐Ling Fong

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Rafik M. Ghobrial

Houston Methodist Hospital

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John A. Goss

Baylor College of Medicine

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John M. Vierling

Baylor College of Medicine

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Abraham Shaked

University of California

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H. Yersiz

University of California

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