Sarah Worley

A Clinical Score to Predict Acute Renal Failure after Cardiac Surgery

The risk of mortality associated with acute renal failure (ARF) after open-heart surgery continues to be distressingly high. Accurate prediction of ARF provides an opportunity to develop strategies for early diagnosis and treatment. The aim of this study was to develop a clinical score to predict postoperative ARF by incorporating the effect of all of its major risk factors. A total of 33,217 patients underwent open-heart surgery at the Cleveland Clinic Foundation (1993 to 2002). The primary outcome was ARF that required dialysis. The scoring model was developed in a randomly selected test set (n = 15,838) and was validated on the remaining patients. Its predictive accuracy was compared by area under the receiver operating characteristic curve. The score ranges between 0 and 17 points. The ARF frequency at each score level in the validation set fell within the 95% confidence intervals (CI) of the corresponding frequency in the test set. Four risk categories of increasing severity (scores 0 to 2, 3 to 5, 6 to 8, and 9 to 13) were formed arbitrarily. The frequency of ARF across these categories in the test set ranged between 0.5 and 22.1%. The score was also valid in predicting ARF across all risk categories. The area under the receiver operating characteristic curve for the score in the test set was 0.81 (95% CI 0.78 to 0.83) and was similar to that in the validation set (0.82; 95% CI 0.80 to 0.85; P = 0.39). In conclusion, a score is valid and accurate in predicting ARF after open-heart surgery; along with increasing its clinical utility, the score can help in planning future clinical trials of ARF.

Outcome of Laparoscopic Radical and Open Partial Nephrectomy for the Sporadic 4 cm. or Less Renal Tumor With a Normal Contralateral Kidney

PURPOSE Nephron sparing surgery provides effective therapy in patients with a solitary sporadic renal tumor 4 cm. or less and a normal contralateral kidney. Laparoscopic radical nephrectomy has been applied as a newer alternative therapy in these patients. These 2 contemporary approaches represent divergent treatment alternatives at centers where laparoscopic nephron sparing surgery is not offered. We compared the short-term and long-term impact of these 2 treatment modalities in patients with a sporadic localized solitary renal tumor 4 cm. or less and a normal opposite kidney. MATERIALS AND METHODS A retrospective review of a contemporary series of patients (1996 to 2001) who underwent open nephron sparing surgery and met study inclusion criteria was performed and compared with a similar cohort (1997 to 2001) that underwent laparoscopic radical nephrectomy. Only patients with a single renal tumor of 4 cm. or less, normal serum creatinine less than 1.5 mg./dl. and a normal contralateral kidney were included in analysis. The 2 groups were compared in regard to demographic, clinical and pathological variables using parametric and nonparametric tests. Linear regression analysis was done to compare the percent change in serum creatinine, while adjusting for demographic and clinical variables, and followup. RESULTS A total of 35 patients who underwent laparoscopic radical nephrectomy and 82 who underwent open nephron sparing surgery met study inclusion criteria. Mean patient age in the laparoscopic group was significantly greater (67.3 versus 56.2 years, p <0.001), mean American Society of Anesthesiologists class score was higher (p = 0.04) and mean tumor size was greater (3.1 versus 2.6 cm., p = 0.003) than in the nephron sparing group. The laparoscopic group had significantly decreased mean blood loss (100 versus 200 ml., p <0.001), hospital stay (1 versus 5 days, p <0.001), narcotic use (16.5 versus 224 mg., p <0.001) and operative time (184.4 versus 216.2 minutes, p <0.007) compared with the nephron sparing group. Patients who underwent nephron sparing surgery experienced less postoperative deterioration in renal function, as measured by the percent increase in serum creatinine postoperatively (0% versus 25%, p <0.001). The results of regression analyses at 4 and 6 months of followup indicated that open nephron sparing surgery is associated with significantly lower serum creatinine than laparoscopic radical nephrectomy after adjusting for demographic and clinical variables, and followup. CONCLUSIONS Open nephron sparing surgery and laparoscopic radical nephrectomy are relatively recent and significant developments for treating patients with renal cell carcinoma and they represent accepted standards of care in those with a small renal mass and normal contralateral kidney. In patients presenting with a sporadic solitary renal tumor of 4 cm. or less and a normal contralateral kidney the significant short-term and intermediate term benefits of the laparoscopic approach must be weighed against the long-term advantage of better renal function associated with open nephron sparing surgery. The distinct advantages of these 2 approaches may ultimately be realized with the standardization of laparoscopic partial nephrectomy.

Feeding difficulties and growth delay in children with hypoplastic left heart syndrome versus d-transposition of the great arteries.

The objective of this study was to identify the incidence of feeding difficulties in infants with hypoplastic left heart syndrome (HLHS) and d-transposition of the great arteries (d-TGA). Congenital heart disease is a risk factor for growth failure. The etiologies include poor caloric intake, inability to utilize calories effectively, and increased metabolic demands. The goals of our study were to (1) identify feeding difficulties in infants with HLHS and d-TGA and (2) assess their growth in the first year of life. We performed a chart review of 27 consecutive infants with HLHS and 26 with d-TGA. Descriptive statistics were generated for demographic and clinical variables within each group and are presented as means ± standard deviations. HLHS and d-TGA groups were compared on time to achieving nutritional goals using the log rank test, on complication rate using the chi-square test, and on weight using the t-test. A significance level of 0.05 was used for all tests. Birth weight was similar for both the HLHS and d-TGA groups (3.19 ± 0.69 vs 3.35 ± 0.65 kg, respectively; p = 0.38). Infants with HLHS weighed less than those with d-TGA at l month (3.29 ± 0.58 vs 3.70 ± 0.60 kg, respectively; p = 0.021), 6 months (6.27 ± 1.06 vs 7.31 ± 1.02 kg, p = 0.003), and 12 months of age (8.40 ± 1.11 vs 9.49 ± 1.01 kg, p = 0.006). Time to achieving full caloric intake (at least 100 kcal/kg/day) for the HLHS group (24 ± 11.9 days) was significantly longer than for the d-TGA group (12.0 ± 11.2 days, p < 0.001). In addition, infants with HLHS had a higher incidence of feeding-related complications that those with d-TGA (48 vs 4%, respectively; p = 0.001). Compared to the d-TGA group, infants with HLHS weighed less at follow-up, took longer to reach nutritional goals, and had a much higher incidence of feeding-related complications.

Factors associated with early extubation after cardiac surgery in young children.

Objective Children undergoing congenital heart surgery require mechanical ventilation. We sought to identify pre- and intraoperative factors (PrO, IO) associated with successful early extubation <24 hrs. Design and Patients We performed a retrospective chart review of children <36 months old who underwent congenital heart surgery from January 1998 to July 1999. Setting Pediatric intensive care unit in a children’s hospital. Measurements Generalized Estimating Equation models were fit to assess the association between PrO and IO and early extubation while accounting for the correlation between surgeries performed on the same patient. Estimated odds ratios (EOR) and 95% confidence intervals were calculated. Multivariable models were constructed using a forward selection process with inclusion criteria of p < .05. Multivariable models, which included PrO and IO variables, were adjusted for procedure group. The area under the receiver operating characteristic curve was computed for each model. Results A total of 203 children underwent 219 surgeries; 103 (47%) children were extubated in <24 hrs, with only one (1%) failed extubation. PrO variables associated with successful early extubation included age >6 months (EOR, 6.1), absence of pulmonary hypertension (EOR, 9.1), gestational age >36 wks (EOR, 4.6), and absence of congestive heart failure (EOR, 2.4). IO variables were less likely to be associated with successful early extubation. Our model of PrO variables with multiple factors showed that presence of two factors was associated with an EOR of 4.2 for successful early extubation compared with children with zero or one factor. Presence of three and four factors was associated with an EOR of 18.0 and 76.5, respectively. The area under the receiver operating characteristic curve for this model is 0.816. Incision type, complex vs. simple procedure, and palliative vs. complete repair were not associated with success of early extubation. Conclusions Early extubation is possible in many very young children undergoing congenital heart surgery, with a low rate of failed extubation. The model would be improved by prospective validation with larger numbers at multiple institutions.

Mechanical Failure of the American Medical Systems Ultrex Inflatable Penile Prosthesis: Before and After 1993 Structural Modification

PURPOSE The 700 Ultrex (American Medical Systems, Minnetonka, Minnesota) is the only penile prosthesis capable of length and girth expansion. Early experience with the 700 Ultrex showed an increased mechanical failure rate compared with the 700CX, mostly secondary to cylinder failure. In 1993 the Ultrex cylinders were modified. We examined the performance of the Ultrex device before and after modification. MATERIALS AND METHODS We compared our results with the Ultrex prosthesis before (group 1) and after (group 2) the 1993 modification. We implanted 239 devices from October 1989 to December 1999. A total of 26 patients have died. Followup was obtained on the results of 137 of the remaining 213 implants (64%), including 85 pre-modification devices in 85 patients and 52 post-modification devices in 51, via a mailed questionnaire, telephone survey or chart review. The questionnaire and survey included a 5-point satisfaction scale. Groups 1 and 2 were compared in regard to 3 end points, namely cylinder, mechanical and overall failure. RESULTS Followup was less than 1 to 136 months (median 92, 25th to 75th percentiles 43 to 108) in group 1 and less than 1 to 92 months (median 46, 25th to 75th percentiles 21 to 75) in group 2. The 5-year Kaplan-Meier estimates of overall, mechanical and cylinder survival in groups 1 and 2 were 64.7%, 70.7% and 80.2%, and 77.7% (p = 0.23), 93.7% (p = 0.017) and 96.2% (p = 0.008), respectively. Overall satisfaction was similarly high in groups 1 and 2 (mean 3.9 and 4 points). CONCLUSIONS On long-term followup the 1993 modification of the Ultrex cylinders appears to have significantly decreased the propensity of cylinder failure of the pre-modification device.

Long-term (5- to 20-year) outcomes after transcatheter or surgical treatment of hemodynamically significant isolated secundum atrial septal defect

Truly long-term follow-up data after transcatheter closure (TC) of atrial septal defects (ASDs) are scarce. We report the 5- to 20-year outcomes of TC and surgical closure (SC) for typical secundum ASD. We reviewed the records of patients with isolated secundum ASD and right ventricular volume overload who underwent TC or SC (January 1, 1986 to September 30, 2005). Follow-up was obtained through a combination of chart review, physician records, and telephone survey. We identified 375 patients (207 SC and 168 TC) and obtained follow-up data >5 years (median follow-up 10 years) for 300 (152 SC, 148 TC). Nine patients have died (3%). The New York Heart Association functional class was unchanged in 227 patients, improved in 25, and was worse in 15. Clinically significant arrhythmia was found in 28 patients (9.3%); 21% aged >40 years developed arrhythmia. On multivariate analysis, the odds of significant arrhythmia tended to be greater in the SC group, but this was statistically insignificant (95% confidence interval 0.68 to 3.9, p = 0.27). Age and preprocedure arrhythmia, but not TC or SC, were independent risk factors for late arrhythmia (p <0.001). No difference was found in the incidence of late, probably embolic, stroke in the TC (3%) versus SC (2%) groups. In conclusion, long-term outcomes after secundum ASD closure using modern methods are excellent. No significant differences were found between TC versus SC with regard to survival, functional capacity, atrial arrhythmias, or embolic neurologic events. Arrhythmia and neurologic events remain long-term risks after ASD closure, especially if the patient had pre-existing arrhythmia.

Increased Mortality After Pulmonary Fungal Infection Within the First Year After Pediatric Lung Transplantation

BACKGROUND Risk factors, morbidity and mortality from pulmonary fungal infections (PFIs) within the first year after pediatric lung transplant have not previously been characterized. METHODS A retrospective, multicenter study from 1988 to 2005 was conducted with institutional approval from the 12 participating centers in North America and Europe. Data were recorded for the first post-transplant year. The log-rank test assessed for the association between PFI and survival. Associations between time to PFI and risk factors were assessed by Cox proportional hazards models. RESULTS Of the 555 subjects transplanted, 58 (10.5%) had 62 proven (Candida, Aspergillus or other) or probable (Aspergillus or other) PFIs within the first year post-transplant. The mean age for PFI subjects was 14.0 years vs 11.4 years for non-PFI subjects (p < 0.01). Candida and Aspergillus species were recovered equally for proven disease. Comparing subjects with PFI (n = 58) vs those without (n = 404), pre-transplant colonization was associated with PFI (hazard ratio [HR] 2.0; 95% CI 0.95 to 4.3, p = 0.067). Cytomegalovirus (CMV) mismatch, tacrolimus-based regimen and age >15 years were associated with PFI (p < 0.05). PFI was associated with any prior rejection higher than Grade A2 (HR 2.1; 95% CI 1.2 to 3.6). Cystic fibrosis, induction therapy, transplant era and type of transplant were not associated with PFI. PFI was independently associated with decreased 12-month survival (HR 3.9, 95% CI 2.2 to 6.8). CONCLUSIONS Risk factors for PFI include Grade A2 rejection, repeated acute rejection, CMV-positive donor, tacrolimus-based regimen and pre-transplant colonization.

Safety and early outcomes using a corticosteroid-avoidance immunosuppression protocol in pediatric heart transplant recipients

BACKGROUND Long-term oral corticosteroids have been a mainstay of maintenance immunosuppression in pediatric heart transplantation. In this study, we report early clinical outcomes in a cohort of pediatric heart transplant recipients managed using a steroid-avoidance protocol. METHODS Of the 70 patients who underwent heart transplantation during the study period, 55 eligible recipients, including 49 non-sensitized and 6 sensitized (all 55 with negative crossmatch) patients, entered a steroid-avoidance immunosuppression protocol consisting of thymoglobin induction followed by a 2-drug, tacrolimus-based, corticosteroid-free regimen. The primary outcome variable was freedom from moderate rejection (International Society for Heart and Lung Transplantation [ISHLT] Grade 2R/3A or antibody-mediated rejection). RESULTS The median age at transplant was 7.1 years (range 2 weeks to 22 years) and median follow-up was 19 months (range 2 to 46 months). Fifty patients survived to discharge after transplantation. Of these patients, 2 (4%) were discharged on steroids and 8 (16%) started on maintenance steroids at follow-up. Rejection was diagnosed in 8 patients (Grade 2R cellular rejection in 3 and antibody-mediated rejection in 5). Freedom from rejection was 92% at 6 months (95% confidence interval [CI] 80% to 97%) and 87% at 1 year (CI 73% to 94%). Post-transplant survival was 91% at 6 months (CI 79% to 96%) and 88% at 12 and 24 months (CI 75% to 95%). There was 1 death due to rejection (antibody-mediated) 8 months after transplantation. CONCLUSIONS An immunosuppression protocol consisting of induction followed by corticosteroid avoidance appears to achieve acceptable rejection rates during the first year post-transplant in pediatric heart transplant recipients.

Respiratory viral infections within one year after pediatric lung transplant.

Abstract: To characterize epidemiology and risk factors for respiratory viral infections (RVI) in pediatric lung transplant recipients within the first post‐transplant year, a retrospective multicenter study of pediatric lung transplant recipients from 1988 to 2005 was conducted at 14 centers in the United States and Europe. Data were recorded for 1 year post transplant. Associations between RVI and continuous and categorical risk factors were assessed using Wilcoxons rank‐sum and χ2 tests, respectively. Associations between time to RVI and risk factors or survival were assessed by multivariable Cox proportional hazards models. Of 576 subjects, 79 subjects (14%) had 101 RVI in the first year post transplant. Subjects with RVI were younger than those without RVI (median ages 9.7, 13; P<0.01). Viruses detected included adenovirus (n=25), influenza (n=9), respiratory syncytial virus (n=21), parainfluenza virus (n=19), enterovirus (n=4), and rhinovirus (n=22). In a multivariable model for time to first RVI, etiology other than cystic fibrosis (CF), younger age, and no induction therapy were independently associated with risk of RVI. Cytomegalovirus serostatus and acute rejection were not associated with RVI. RVI was independently associated with decreased 12‐month survival (hazard ratio 2.6, 95% confidence interval 1.6–4.4). RVI commonly occurs after pediatric lung transplantation with risk factors including younger age and non‐CF diagnosis. RVI is associated with decreased 1‐year survival.

The risk, prevention, and outcome of cytomegalovirus after pediatric lung transplantation.

Background. A retrospective review of pediatric lung transplant recipients at 14 centers in North America and Europe was conducted to characterize the epidemiology and the risk factors for cytomegalovirus (CMV) and to explore the impact of preventative antiviral therapy. Methods. Data were recorded for 1 year posttransplant. Associations between CMV and continuous and categorical risk factors were assessed using Wilcoxon rank sum and chi-square tests, respectively. Associations between time to CMV and risk factors or survival were assessed by multivariable Cox proportional hazards models. Results. Within 12 months posttransplant, 172 of 577 subjects (29.8%) developed 218 CMV episodes (90 asymptomatic infection, 25 syndrome, and 103 disease). Forty-one subjects developed more than one episode of CMV. Donor or recipient CMV seropositivity was associated with increased risk of CMV episodes. Except for decreased prophylaxis in CMV D−/R− subjects, duration of prophylaxis did not vary by D/R serostatus. For CMV D+ subjects, not being on prophylaxis at the time of CMV episode increased the risk of CMV (D+/R+ hazard ratio 3.5, 95% confidence interval 1.4–8.4; D+/R− 1.9, 1.02–3.7). CMV was associated with increased mortality within the first posttransplant year among those with donor or recipient CMV seropositivity (hazard ratio 2.0: 95% confidence interval 1.1–3.6; P=0.024). Conclusions. CMV remains a serious complication after pediatric lung transplant, and the impact of prophylaxis is complex.