Use of end-tidalPco 2 and transcutaneousPco 2 as noninvasive measurement of arterialPco 2 in extubated patients recovering from general anesthesia

This study was designed to assess the accuracy of end-tidalPco ₂ and transcutaneousPco ₂ as measurements of arterialPco ₂ in extubated, spontaneously breathing patients recovering from general anesthesia. In 30 patients, measurement of arterial transcutaneous, and end-tidalPco ₂ were taken simultaneously with body temperature approximately every 15 minutes over a 2-hour period. ArterialPco ₂ values were corrected for body temperature. Values for Paco ₂ were compared with those forPetCO₂ and Psco ₂ by linear regression analysis and by calculation of bias ± precision. Thirty-six percent of the capnogram tracings obtained did not develop a plateau phase. We found poor correlation between end-tidal and arterialPco ₂ regardless of the shape of the capnogram tracing, as well as poor correlation between transcutaneous and arterialPco ₂. Although the measurements of bias and precision of noninvasivePco ₂ monitors in this population are comparable to studies in other populations, we advise caution in relying on the routine use ofPetCO₂ or Psco ₂ for the noninvasive assessment of respiratory depression in extubated, spontaneously breathing patients recovering from general anesthesia.     

Modification of Gastric Banding,Using a Fundal Suture

Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification are presented.     

Keeping time: effects of focal frontal lesions

This study examined the performance of 32 normal subjects and 39 patients with focal lesions of the frontal lobes on two simple timing tasks-responding in time with a tone that regularly repeated at a rate of once every 1.5s, and then maintaining the same regular response rhythm without any external stimulus. The hypothesis was that lesions to the right prefrontal cortex would disrupt timing performance. The two main findings were (1) an abnormally high variability in the timing performance (both self-timed and tone-timed) of patients with lesions to the right lateral frontal lobe, particularly involving Brodmann area 45 and subjacent regions of the basal ganglia; (2) an increase in the variability of timing performance as the task continued in patients with lesions to the superior medial regions of the frontal lobe. These findings indicate that the right lateral frontal lobe is crucially involved in the ongoing control of timed behavior, either because of its role in generating time intervals or in monitoring the passage of these intervals. In contrast, the superior medial regions of the frontal lobe are necessary to maintain consistent timing performance over prolonged periods of time.     

Mitotic Rate as a Predictor of Sentinel Lymph NodePositivity in Patients With Thin Melanomas

Background Lymphatic mapping and sentinel lymphadenectomy (LM/SL) provide important prognostic information for patients with early-stage melanoma. Although the use of this technique in patients with thin melanomas (1.00 mm) is not routine, risk factors that may predict sentinel lymph node (SLN) positivity in this patient population are under investigation. We sought to determine whether mitotic rate (MR) is associated with SLN positivity in thin-melanoma patients and, therefore, whether it may be used to risk-stratify and select patients for LM/SL.Methods Clinical and histopathologic variables were reviewed for 181 patients with thin melanomas who underwent LM/SL from January 1996 through January 2004. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SLN positivity. Risk groups were defined on the basis of the development of a classification tree.Results The overall SLN positivity rate was 5%. All patients with positive SLNs had an MR of >0. By univariate analysis, MR and thickness were significant predictors of SLN positivity. The association between MR and SLN positivity remained significant controlling for each of the other variables evaluated. On the basis of a classification tree, patients with an MR >0 and tumor thickness .76 mm were identified as a higher-risk group, with an SLN positivity rate of 12.3%.Conclusions In patients with thin melanomas, MR >0 seems to be a significant predictor of SLN positivity that may be used to risk-stratify and select patients for LM/SL. To confirm these results, the predictive value of MR for SLN positivity needs to be validated in other populations of thin-melanoma patients.Published by Springer Science+Business Media, Inc. © 2005 The Society of Surgical Oncology, Inc.     

Hyperlipidemia in pediatric kidney transplant recipients treated with cyclosporine

Hyperlipidemia is a risk factor for cardiovascular disease in adult kidney transplant (Tx) recipients. We sought to determine the prevalence of, and the risk factors associated with, hyperlipidemia in pediatric kidney Tx recipients on cyclosporine (CsA). We identified 59 patients (mean age 8.2+/-5.7 years) transplanted between 1 January 1991 and 31 December 1993. Pre Tx, 34% had elevated total cholesterol [TC >200 mg/dl (5.17 mmol/l)]; 54% had elevated triglycerides [TG >200 mg/dl (2.26 mmol/L)]. Mean TG was higher pre Tx in dialysis (versus nondialysis) patients: 306 mg/dl (3.46 mmol/l) versus 228 mg/dl (2.58 mmol/l) ( P=0.04). Mean TC was higher in peritoneal dialysis than hemodialysis patients: 222 mg/dl (5.74 mmol/l) versus 169 mg/dl (4.37 mmol/l) ( P=0.03). Pre Tx and 3-year values correlated (TC, r=0.49, P=0.0008; TG, r=0.41, P=0.001); 3- and 5-year TC values correlated ( r=0.57, P=0.003). At 5 years post Tx, 41% of the recipients had elevated TC; 14% had elevated TG. Recipients with elevated TC had higher mean CsA concentrations at 1 year post Tx ( P=0.03). Recipients with elevated TG tended to receive more prednisone ( P=0.06). At 5 years post Tx, recipients had a high prevalence of hyperlipidemia. The identification and treatment of hyperlipidemia should be included in pediatric kidney Tx protocols.     

Predicting long-term kidney graft survival: can new trials be performed?

BACKGROUND: As short-term transplant results improve, it has become difficult to use patient or graft survival or acute rejection as clinical trial endpoints, except in large, multicenter studies. Despite better outcomes, graft failure continues over time. METHODS: We studied 6- and 12-month creatinine (Cr) level and change in creatinine (deltaCr) level (3-12 months, 6-12 months) as predictors of graft survival for 1,389 primary kidney transplants (minimum graft survival 1 year). Determining the prognostic value of Cr level (6 or 12 months), the subgroups were as follows: less than 1, 1 to 1.4, 1.5 to 1.9, 2.0 to 2.4, 2.5 to 2.9, and greater than or equal to 3 mg/dL. For deltaCr level, the subgroups were as follows: less than 0, 0, 0.01 to 0.2, and greater than 0.2. Subgroup actuarial graft survival was determined. Cox regression analyses were performed with forward, stepwise selection. RESULTS: After 12-month Cr level entered the model, no other variable was significant. Repeating this with continuous variables, 12-month Cr level was again the best predictor. Five-year graft survival for 12-month Cr level less than 1 (n=38) was 95%; for 1.0 to 1.4 (n=454), 87%; for 1.5 to 1.9 (n=463), 86%; for 2.0 to 2.4 (n=166), 78%; for 2.5 to 2.9 (n=54), 60%; for greater than or equal to 3 (n=45), 41%. A major breakpoint for outcome is 1-year Cr level=2.0. A power analysis was performed for the combined endpoint of graft loss and 1-year Cr level greater than 2, reached by 30% of patients. To avoid missing a reduction to 20% (actual decrease 33%) (alpha=0.05; power=0.8), 313 patients would be required per group. For a reduction to 15% (actual decrease 50%), 133 patients would be required. CONCLUSIONS: Twelve-month Cr level is an accurate surrogate for long-term outcome. The use of a combined endpoint (graft loss and 12-month Cr level) allows trials to be performed without exorbitant numbers.