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S McDiarmid

Publications and source records attributed to S McDiarmid.

18 recordsLinked to original sources
PubMed2002

Outpatient total body irradiation as a component of a comprehensive outpatient transplant program.

Outpatient total body irradiation (TBI) as part of a comprehensive outpatient transplant program was delivered to 142 of 167 (85%) consecutive patients receiving TBI-based conditioning therapy. Outpatients received either a single fraction of 500 cGy (110 patients) or 1200 cGy in six fractions over 3 days (32 patients). Patients were assessed daily and were administered oral ondansetron and dexamethasone for prophylaxis of nausea and vomiting as well as i.v. hydration. Accommodation during outpatient TBI-based conditioning was either the patient's home if within 30 min of the hospital, a hotel on the hospital grounds or on a closed hospital ward. None of the 142 patients required admission to the inpatient program during their TBI. There was no difference in 100-day mortality between those receiving TBI as an outpatient (9%) vs as an inpatient (16%). Of four deaths occurring within the first 14 days post transplant, none could be attributed to receiving TBI as an outpatient. Two hundred and six inpatient days were saved through the delivery of outpatient TBI. A comprehensive outpatient program, appropriate patient selection, daily hydration, the use of prophylactic 5HT3 antagonist anti-emetic therapy all contribute to the safe delivery of outpatient TBI.

Adolescent↗
PubMed2001

A randomized double-blind comparative study of mycophenolate mofetil and azathioprine in combination with cyclosporine and corticosteroids in primary liver transplant recipients.

Acute hepatic allograft rejection occurs in approximately 50% to 60% of the patients undergoing liver transplantation. In this study, we compared the rate of acute rejection in liver transplant recipients randomized in a double-blind comparative study to treatment with mycophenolate mofetil (MMF) or azathioprine (AZA), both in combination with cyclosporine and corticosteroids. Five hundred sixty-five primary liver transplant recipients were randomly assigned to treatment with MMF, 1 g twice daily intravenously followed by 1.5 g twice daily orally (n = 278), or AZA, 1.0 to 2.0 mg/kg/d intravenously followed by oral administration (n = 287), in combination with cyclosporine and corticosteroids. Patients were followed up for at least 1 year, and efficacy analysis was based on intent-to-treat methods. Acute rejection was defined according to the Banff histological criteria. The two study groups were balanced for demographic and clinical baseline characteristics. The incidence of acute rejection or graft loss was 47.7% in the AZA patients and 38.5% in the MMF patients (P <.03). The incidence of biopsy-proven and treated rejection censoring for graft loss was 40.0% in the AZA group versus 31.0% in the MMF group (P <.06). Steroid-resistant rejection requiring treatment with either OKT3 or antithymocyte globulin occurred in 8.2% of AZA patients versus 3.8% in MMF patients (P <.02). Patient and graft survival rates at 1 year posttransplantation were 85.4% in the AZA group and 85.3% in the MMF group (P = not significant). MMF was superior to AZA in preventing acute rejection in the first 6 months posttransplantation. MMF and AZA were equivalent in preventing graft loss at 1 year, and the safety profiles between the two immunosuppressive agents were similar.

Acute Disease↗
PubMed1999

Selection of appropriate venous access for the collection of peripheral blood progenitor cells by experienced apheresis nurses.

Peripheral blood progenitor cells (PBPC) have been extensively used to restore hematopoiesis after myeloablative chemotherapy. While collection regimens designed for optimal mobilization of PBPC are becoming standardized, the ideal venous access option for collection remains unresolved. The purpose of this study was to determine if the venous access of patients could be accurately assessed and appropriate intervention, if necessary, electively undertaken prior to PBPC collection. In this prospective study, 95 consecutive patients about to undergo PBPC collection were evaluated at time of referral to determine the type of venous access necessary for adequate PBPC collection. There were three possible interventions: 1. No access device for patients determined to have an adequate antecubital vein for apheresis access. 2. Insertion of a double lumen Quinton PermCath for those patients with poor antecubital veins. 3. Insertion of a double lumen Hickman catheter for patients with adequate antecubital veins for apheresis but poor peripheral veins for chemotherapy administration. The blood and marrow transplant nurse coordinator evaluated the patients' veins. Of the 95 patients having 192 PBPC collections, 65 were collected using antecubital veins, 21 were collected from PermCaths, and 9 from Hickman catheters. All patients predicted to collect peripherally did so and achieved flow rates equivalent to the PermCath. No patient required urgent line placement at time of PBPC collection. There was no difference in the number of cells collected between the three groups. The result of this study strongly supports a policy of appropriate venous access based on patient vein assessment by experienced nurses.

Adolescent↗
PubMed1999

Improved cyclosporine bioavailability in black pediatric liver transplant recipients after administration of the microemulsion formulation.

Black transplant recipients are associated with low cyclosporine bioavailability, which may contribute to the poorer clinical outcomes observed with these patients. In this analysis, we compared cyclosporine exposure in black (n = 9) and nonblack (n = 18) pediatric maintenance liver transplant recipients by using steady-state pharmacokinetic profiles obtained after administration of the original and microemulsion formulations of cyclosporine. Treatment with the original cyclosporine formulation resulted in lower mean dose-normalized, area under the concentration-versus-time curve values for black compared with nonblack pediatric liver transplant recipients. On conversion to the microemulsion formulation of cyclosporine, black and nonblack patients experienced increases in cyclosporine bioavailability of 102% and 39%, respectively (P =.009 and P =.001). Because the increase in mean bioavailability was substantially greater for blacks, area under the concentration-versus-time curve values for this pediatric subpopulation became similar to those levels obtained for nonblacks receiving the microemulsion formulation for cyclosporine. When patients were further stratified by age, ethnic differences in bioavailability with the original formulation of cyclosporine were most apparent in the 1- to 5-year age group. Conversion to the microemulsion formulation resulted in a 164% increase (P =.05) in bioavailability for black patients within this age group such that, again, these levels became similar to area under the concentration-versus-time curve values obtained for young nonblacks receiving cyclosporine for microemulsion. Improvements in cyclosporine bioavailability after administration of the microemulsion formulation of cyclosporine may translate to improved long-term graft and patient outcomes for black pediatric liver transplant recipients.

Adolescent↗
PubMed1998

A randomized trial of granulocyte colony-stimulating factor (Neupogen) starting day 1 vs day 7 post-autologous stem cell transplantation.

The purpose of the study was to evaluate the effect of delayed granulocyte colony-stimulating factor (G-CSF) use on hematopoietic recovery post-autologous peripheral blood progenitor cell (PBPC) transplantation. Patients were randomized to begin G-CSF on day +1 or day +7 post transplantation. Thirty-seven patients with lymphoma or myeloma undergoing high-dose therapy and autologous PBPC rescue were randomized to daily subcutaneous G-CSF beginning on day +1 or day +7 post-transplant. Patients < or =70 kg received 300 microg/day and >70 kg 480 microg/day. All patients were reinfused with PBPCs with a CD34+ cell count >2.0 x 10(6)/kg. Baseline characteristics of age, sex and CD34+ cell count were similar between the two arms, the median CD34+ cell count being 5.87 x 10(6)/kg in the day +1 group and 7.70 x 10(6)/kg in the day +7 group (P=0.7). The median time to reach a neutrophil count of >0.5 x 10(9)/l was 9 days in the day +1 arm and 10 days in the day +7 arm, a difference which was not statistically significant (P=0.68). Similarly, there was no difference in median days to platelet recovery >20000 x 10(9)/l, which was 10 days in the day +1 arm and 11 days in the day +7 arm (P=0.83). There was also no significant difference in the median duration of febrile neutropenia (4 vs 6 days; P=0.7), intravenous antibiotic use (7 vs 8 days; P=0.54) or median number of red blood cell transfusions (4 vs 7 units; P=0.82) between the two arms. Median length of hospital stay was 11 days post-PBPC reinfusion in both groups. The median number of G-CSF injections used was 8 in the day +1 group and 3 in the day +7 group (P < 0.0001). There is no significant difference in time to neutrophil or platelet recovery when G-CSF is initiated on day +7 compared to day +1 post-autologous PBPC transplantation. There is also no difference in number of febrile neutropenic or antibiotic days, number of red blood cell transfusions or length of hospital stay. The number of doses of G-CSF used per transplant is significantly reduced with delayed initiation, resulting in a significant reduction in drug costs. For patients with an adequately mobilized PBPC graft, the initiation of G-CSF can be delayed until day +7 post-PBPC reinfusion.

Adult↗
PubMed1997

Efficacy of tacrolimus as rescue therapy for chronic rejection in orthotopic liver transplantation: a report of the U.S. Multicenter Liver Study Group.

BACKGROUND: A study was performed by 17 different U.S. liver transplantation centers to determine the safety and efficacy of conversion from cyclosporine to tacrolimus for chronic allograft rejection. METHODS: Ninety-one patients were converted to tacrolimus a mean of 319 days after liver transplantation. The indication for conversion was ongoing chronic rejection confirmed by biochemical and histologic criteria. Patients were followed for a mean of 251 days until the end of the study. RESULTS: Sixty-four patients (70.3%) were alive with their initial hepatic allograft at the conclusion of the study period and were defined as the responder group. Twenty-seven patients (29.7%) failed to respond to treatment, and 20 of them required a second liver graft. The actuarial graft survival for the total patient group was 69.9% and 48.5% at 1 and 2 years, respectively. The actuarial patient survival at 1 and 2 years was 84.4% and 81.2%, respectively. Two significant positive prognostic factors were identified. Patients with a total bilirubin of < or = 10 mg/dl at the time of conversion had a significantly better graft and patient survival than patients converted with a total bilirubin > 10 mg/dl (P=0.00002 and P=0.00125, respectively). The time between liver transplantation and conversion also affected graft and patient survival. Patients converted to tacrolimus < or = 90 days after transplantation had a 1-year actuarial graft and patient survival of 51.9% and 65.9%, respectively, compared with 73.2% and 87.7% for those converted > 90 days after transplantation. The mean total bilirubin level for the responder group was 7.1 mg/dl at the time of conversion and decreased significantly to a mean of 3.4 mg/dl at the end of the study (P=0.0018). Thirteen patients (14.3%) died during the study. Sepsis was the major contributing cause of death in most of these patients. CONCLUSIONS: Our results suggest that conversion to tacrolimus for chronic rejection after orthotopic liver transplantation represents an effective therapeutic option. Conversion to tacrolimus before development of elevated total bilirubin levels showed a significant impact on long-term outcome.

Adolescent↗
PubMed1997

Pharmacokinetics of an oral solution of the microemulsion formulation of cyclosporine in maintenance pediatric liver transplant recipients.

BACKGROUND: A comparison of the oral bioavailability of cyclosporine from the original formulation (CsA) and from the new formulation, cyclosporine for microemulsion (CsA-ME), was made in pediatric maintenance liver transplant patients within two age groups (group 1, ages 1-5 years; group 2, ages 6-17 years) in an open-label, multicenter, randomized crossover trial. All patients were at least 6 months past transplantation and were receiving CsA maintenance therapy. METHODS: In study period 1 (days 1 through 14), patients were administered either CsA or CsA-ME at the same b.i.d. dosage as their maintenance therapy. Upon entry into period 2 (days 15 through 28), patients were converted to the alternate formulation at a 1:1 mg dose ratio. On day 29, all patients returned to the CsA treatment administered at study entry, with follow-up on day 35. Dosage adjustments were not allowed with either CsA or CsA-ME. Twelve-hour pharmacokinetic profiling was performed at the end of periods 1 and 2. RESULTS: Both the mean area under the concentration-versus-time curve and the mean maximum blood concentration of cyclosporine-both normalized for dose-were significantly increased: by 66% and 109%, respectively, in patients receiving CsA-ME compared with those receiving CsA in group 1 and by 39% and 75%, respectively, in group 2. During this study, liver function remained stable, and serum creatinine and blood pressure did not differ significantly between treatment groups. CONCLUSIONS: This study shows increased bioavailability in all patients converted to CsA-ME, with the greatest increase seen in patients with the lowest initial cyclosporine bioavailability. The tolerability was similar between the two formulations during this study.

Absorption↗
PubMed1997

Delayed encephalopathy in fulminant hepatic failure in the pediatric population and the role of liver transplantation.

BACKGROUND: Liver transplantation is the therapeutic choice for fulminant hepatic failure in children. METHODS: All 66 cases of fulminant hepatic failure in the pediatric population seen at UCLA from May, 1985 to November, 1993 were reviewed to determine changes in survival rates since the advent of liver transplantation. We evaluated the clinical course and events leading to the exclusion of surgical management of nonsurvivors, who otherwise would have benefited from a liver transplant. We also compared the latter's clinical course with the nontransplant survivors to determine parameters for screening patients for liver transplantation. RESULTS: Fifty-one patient (77%) were put on the transplant list initially but eventually, only 38 (58%) patients underwent orthotopic liver transplantation (OLT) and of these 30 (79%) patients survived. Of the remaining 29 (42%) patients who did not undergo liver transplantation, only 10 (36%) patients survived. Nine patients died while waiting for a donor liver secondary to complications of hepatic failure. The majority of nonsurvivors in the OLT and no-OLT groups succumbed because of irreversible neurologic deterioration. In the no-OLT group, comparisons between survivors and non-survivors were made. There were no significant demographic differences. It took a mean of 8 days (+/-8) versus 22 days (+/-15), (p = 0.009), from onset of illness to first hospital admission for survivors and nonsurvivors, respectively. Time to reach stage II encephalopathy was a mean of 5 days (+/-5) for survivors versus 18 days (+/-16), (p = 0.05) for nonsurvivors. Nonsurvivors were transferred to the transplant center at a mean of 12.2 days (+/-12) after being first admitted elsewhere as compared to a mean of 1.9 days (+/-18) for survivors, (p = 0.02). Mean prothrombin time decreased by a mean of 13.4 s/day (+/-16) for survivors as against 2.25 s/day (+/-6) for nonsurvivors, (p = 0.06). Mean peak total bilirubin for nonsurvivors was 460 mumol/L (27 mg/dl) versus 220 mumol/L (13 mg/dl) for survivors, (p = 0.06). Nonsurvivors died at a mean of 30 days (+/-19) from onset and survivors' liver tests started to improve at a mean of 11 days (+/-9) from onset. CONCLUSIONS: From these studies, we conclude that liver transplantation remains the therapeutic choice for fulminant hepatic failure in children. Early referral and closer follow-up is necessary for timely admission to liver transplant centers to enable screening and proper preparation of these patients for liver transplantation.

Adolescent↗
PubMed1996

Graft loss following liver transplantation in patients with chronic hepatitis C.

Liver disease due to hepatitis C (HCV) is an increasingly frequent indication for orthotopic liver transplantation (OLT). The aim of the current study was to analyze the causes of graft loss following OLT for chronic hepatitis C and the longterm outcome following retransplantation in a large university program. Between January 1990 and December 1995, 1183 patients underwent primary OLT at our center. In 304 patients, HCV was diagnosed by seropositivity and/or polymerase chain reaction. Fifty-six (18.4%) of these patients underwent retransplantation. The 36 patients retransplanted for primary non-function were excluded from further analysis. The other indications for regrafting (>30 days following primary transplant) included hepatic artery thrombosis (5), chronic rejection (4), severe HCV recurrence (5), and other etiologies (6). The cumulative survival rates for the 248 patients who received 1 OLT (group 1) were 84% after one year and 75% after three years. The corresponding rates for the 20 non-PNF patients who were retransplanted (group 2) were 60% and 43%, respectively (P<.0001). Moreover, logistic regression analysis confirmed that patients in group 2 were more than 4 times likely to die than patients in group 1 (P<.0034; risk ratio, 4.2; 95% confidence interval 1.61 to 11.37). Patients undergoing retransplantation had a high incidence of serious infectious complications leading to mortality. Two additional patients with severe recurrent HCV died awaiting liver retransplantation. Eight of the 304 total patients (2.6%) transplanted for chronic HCV developed graft failure secondary to HCV recurrence and 6 of the 8 were retransplanted; 3 of the 6 patients retransplanted are alive without evidence of histologic recurrence (mean follow-up less than 1 year). In summary, despite the high frequency of recurrent histologic evidence of HCV following primary OLT (70% at 3 years), graft loss attributable solely to HCV is an infrequent finding. Retransplantation per se is a risk factor for a fatal outcome, and the indication for reOLT does not appear to impact ultimate outcome. Serious infectious complications were the leading cause of mortality in patients retransplanted. Furthermore, given the indolent natural history of HCV, longer follow-up is necessary to determine the ultimate rate of graft loss due to HCV recurrence.

Biopsy↗
PubMed1992

Excessive chromium intake in children receiving total parenteral nutrition.

Various expert bodies have recommended that the daily parental intake of chromium in children receiving total parenteral nutrition (TPN) should be 0.20 micrograms/kg. To test whether this recommendation is appropriate, we assessed chromium intake, serum chromium concentrations, and renal function in 15 children receiving TPN. The median duration of TPN use was 9.5 (range 1.3-14) years. The children's glomerular filtration rate (GFR), measured by plasma clearance of indium-111-DTPA was lower than that of non-TPN controls (70 [SD 17] vs 110 [10] ml/min per 1.73 m2). The daily chromium intake averaged 0.15 (0.09) micrograms/kg daily but the serum chromium concentration was 20 (4 to 42) times higher than that of the controls (2.1 [1.2] vs 0.10 [0.03] micrograms/l; p less than 0.0001). GFR was significantly inversely correlated with serum chromium concentration (r = -0.60, p less than 0.02), daily chromium intake (r = -0.69, p less than 0.01), cumulative parenteral chromium intake (r = -0.72, p less than 0.01), and TPN duration (r = -0.52, p less than 0.05). We discontinued chromium supplementation of TPN solutions and reassessed the children a year later. Contaminating chromium concentrations were 1.0-1.8 micrograms/l in TPN solutions and 0.9 micrograms/l in fat emulsions. Drinking water contained 4.3-5.7 micrograms/l. Thus, the chromium intake without supplementation was only 0.05 (0.01) micrograms/kg daily. The mean serum chromium concentration fell to 0.50 (0.30) micrograms/l but was still significantly higher than that in the controls (p less than 0.01). The GFR did not change significantly (65 [14] ml/min per 1.73 m2). No patient has shown signs of chromium deficiency. Although our patients were receiving less than the recommended chromium intake during supplementation, their high serum concentrations suggested excessive intake. The recommended parenteral chromium intake for children should be lowered.

Adolescent↗
PubMedDate not supplied

Continuing nursing education: what resources do bedside nurses use?

Continuing nursing education (CNE) has traditionally been considered a formalized learning experience. However, the results of this study indicated nurses providing direct patient care in a tertiary care hospital seldom participate in such activities. The nursing staff do use a variety of resources, both material and personnel, to meet their immediate learning needs. Most of their CNE activities appear to be undertaken within their work environment. The results of this study provide nurse educators and managers insight into how they can augment "on-the-job" learning opportunities for staff nurses.

Adult↗