TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: To examine peripheral nerve stimulation (PNS) thresholds for normal human subjects in magnetic resonance imaging (MRI) gradient coils, and determine if observed thresholds could be predicted based on gross physiologic measurements.', 'PNS thresholds for 21 healthy normal subjects were measured using a whole-body gradient coil. Subjects were exposed to a trapezoidal echo-planar imaging (EPI) gradient waveform and the total change in gradient strength (DeltaG) required to cause PNS as a function of the duration of the gradient switching time (tau) were measured. Correlation coefficients and corresponding P values were calculated for the PNS threshold measurements against simple physiologic measurements taken of the subjects, including weight, height, girth, and average body fat percentage, in order to determine if there were any easily observable dependencies.', 'No convincing correlations between threshold parameters and gross physiologic measurements were observed.\Question: Do simple anatomical measurements correlate significantly to individual peripheral nerve stimulation thresholds as measured in MRI gradient coils?

SOLUTION: These results suggest it is unlikely that a simple physiologic measurement of subject anatomy can be used to guide the operation of MRI scanners in a subject-specific manner in order to increase gradient system performance while avoiding PNS.

PROBLEM: Context: The use of a system for continuous control of endotracheal tube cuff pressure reduced the incidence of ventilator-associated pneumonia (VAP) in one randomized controlled trial (RCT) with 112 patients but not in another RCT with 142 patients. In several guidelines on the prevention of VAP, the use of a system for continuous or intermittent control of endotracheal cuff pressure is not reviewed. The objective of this study was to compare the incidence of VAP in a large sample of patients (n=284) treated with either continuous or intermittent control of endotracheal tube cuff pressure.', 'We performed a prospective observational study of patients undergoing mechanical ventilation during more than 48 hours in an intensive care unit (ICU) using either continuous or intermittent endotracheal tube cuff pressure control. Multivariate logistic regression analysis (MLRA) and Cox proportional hazard regression analysis were used to predict VAP. The magnitude of the effect was expressed as odds ratio (OR) or hazard ratio (HR), respectively, and 95% confidence interval (CI).', 'We found a lower incidence of VAP with the continuous (n=150) than with the intermittent (n=134) pressure control system (22.0% versus 11.2%; p=0.02). MLRA showed that the continuous pressure control system (OR=0.45; 95% CI=0.22-0.89; p=0.02) and the use of an endotracheal tube incorporating a lumen for subglottic secretion drainage (SSD) (OR=0.39; 95% CI=0.19-0.84; p=0.02) were protective factors against VAP. Cox regression analysis showed that the continuous pressure control system (HR=0.45; 95% CI=0.24-0.84; p=0.01) and the use of an endotracheal tube incorporating a lumen for SSD (HR=0.29; 95% CI=0.15-0.56; p<0.001) were protective factors against VAP. However, the interaction between type of endotracheal cuff pressure control system (continuous or intermittent) and endotracheal tube (with or without SSD) was not statistically significant in MLRA (OR=0.41; 95% CI=0.07-2.37; p=0.32) or in Cox analysis (HR=0.35; 95% CI=0.06-1.84; p=0.21).\Question: Does continuous endotracheal tube cuff pressure control system protect against ventilator-associated pneumonia?

SOLUTION: The use of a continuous endotracheal cuff pressure control system and/or an endotracheal tube with a lumen for SSD could help to prevent VAP in patients requiring more than 48 hours of mechanical ventilation.

PROBLEM: Context: To investigate the impact of minimum tacrolimus (TAC) on new-onset diabetes mellitus (NODM) after liver transplantation (LT).', 'We retrospectively analyzed the data of 973 liver transplant recipients between March 1999 and September 2014 in West China Hospital Liver Transplantation Center. Following the exclusion of ineligible recipients, 528 recipients with a TAC-dominant regimen were included in our study. We calculated and determined the mean trough concentration of TAC (cTAC) in the year of diabetes diagnosis in NODM recipients or in the last year of the follow-up in non-NODM recipients. A cutoff of mean cTAC value for predicting NODM 6 mo after LT was identified using a receptor operating characteristic curve. TAC-related complications after LT was evaluated by (2) test, and the overall and allograft survival was evaluated using the Kaplan-Meier method. Risk factors for NODM after LT were examined by univariate and multivariate Cox regression.', 'Of the 528 transplant recipients, 131 (24.8%) developed NODM after 6 mo after LT, and the cumulative incidence of NODM progressively increased. The mean cTAC of NODM group recipients was significantly higher than that of recipients in the non-NODM group (7.66 3.41 ng/mL vs 4.47 2.22 ng/mL, P < 0.05). Furthermore, NODM group recipients had lower 1-, 5-, 10-year overall survival rates (86.7%, 71.3%, and 61.1% vs 94.7%, 86.1%, and 83.7%, P < 0.05) and allograft survival rates (92.8%, 84.6%, and 75.7% vs 96.1%, 91%, and 86.1%, P < 0.05) than the others. The best cutoff of mean cTAC for predicting NODM was 5.89 ng/mL after 6 mo after LT. Multivariate analysis showed that old age at the time of LT (> 50 years), hypertension pre-LT, and high mean cTAC ( 5.89 ng/mL) after 6 mo after LT were independent risk factors for developing NODM. Concurrently, recipients with a low cTAC (< 5.89 ng/mL) were less likely to become obese (21.3% vs 30.2%, P < 0.05) or to develop dyslipidemia (27.5% vs 44.8%, P <0.05), chronic kidney dysfunction (14.6% vs 22.7%, P < 0.05), and moderate to severe infection (24.7% vs 33.1%, P < 0.05) after LT than recipients in the high mean cTAC group. However, the two groups showed no significant difference in the incidence of acute and chronic rejection, hypertension, cardiovascular events and new-onset malignancy.\Question: Does minimizing tacrolimus decrease the risk of new-onset diabetes mellitus after liver transplantation?

SOLUTION:
A minimal TAC regimen can decrease the risk of long-term NODM after LT. Maintaining a cTAC value below 5.89 ng/mL after LT is safe and beneficial.