Predicting the serum digoxin concentrations of infants in the neonatal intensive care unit through an artificial neural network.

BACKGROUND: Given its narrow therapeutic range, digoxin's pharmacokinetic parameters in infants are difficult to predict due to variation in birth weight and gestational age, especially for critically ill newborns. There is limited evidence to support the safety and dosage requirements of digoxin, let alone to predict its concentrations in infants. This study aimed to compare the concentrations of digoxin predicted by traditional regression modeling and artificial neural network (ANN) modeling for newborn infants given digoxin for clinically significant patent ductus arteriosus (PDA). METHODS: A retrospective chart review was conducted to obtain data on digoxin use for clinically significant PDA in a neonatal intensive care unit. Newborn infants who were given digoxin and had digoxin concentration(s) within the acceptable range were identified as subjects in the training model and validation datasets, accordingly. Their demographics, disease, and medication information, which were potentially associated with heart failure, were used for model training and analysis of digoxin concentration prediction. The models were generated using backward standard multivariable linear regressions (MLRs) and a standard backpropagation algorithm of ANN, respectively. The common goodness-of-fit estimates, receiver operating characteristic curves, and classification of sensitivity and specificity of the toxic concentrations in the validation dataset obtained from MLR or ANN models were compared to identify the final better predictive model. RESULTS: Given the weakness of correlations between actual observed digoxin concentrations and pre-specified variables in newborn infants, the performance of all ANN models was better than that of MLR models for digoxin concentration prediction. In particular, the nine-parameter ANN model has better forecasting accuracy and differentiation ability for toxic concentrations. CONCLUSION: The nine-parameter ANN model is the best alternative than the other models to predict serum digoxin concentrations whenever therapeutic drug monitoring is not available. Further cross-validations using diverse samples from different hospitals for newborn infants are needed.

Therapeutic effect of laparoscopy-assisted D2 radical gastrectomy in 106 patients with advanced gastric cancer.

PURPOSE: To explore the feasibility and short-term effect of laparoscopy-assisted D2 radical gastrectomy for advanced gastric cancer. METHODS: A total of 239 patients with advanced gastric cancer underwent D2 radical gastrectomy between March 2009 and June 2011, from which 106 patients underwent laparoscopic surgery (laparoscopy group) and 133 patients underwent open surgery (open surgery group). The intraoperative and postoperative condition, number of lymph node removed, complications and mortality rates between the two groups were compared. RESULTS: The operation time (268±51 min) and the number of lymph node removed (29.1+6.1) in the laparoscopy group were comparable with the operation time (268±49 min) and the number of lymph node removed (30.2±7.0) in the open surgery group, while there were significant differences in the intraoperative bleeding (134±66 vs 289±139 ml), intraoperative blood infusion cases (5 vs 19), time to first postoperative flatus (3.4±0.9 vs 5.0±1.4 days), time to first taking liquid food (7.3±1.3 vs 8.1±1.4 days) and postoperative hospital stay (12.8±2.6 vs 14.5±3.1 days) between the two groups (p<0.05). These results favored the laparoscopy group. The incidence of postoperative complications in the laparoscopy and open surgery group were 14.1 and 24.8, respectively (p<0.05). Compared with the open surgery, the laparoscopic surgery significantly reduced the incidence of pulmonary infection (p<0.05). There was no significant difference in the postoperative short-term survival rate between the two groups (p>0.05). CONCLUSION: Laparoscopy-assisted D2 gastrectomy for advanced gastric cancer is advantageous in terms of safety and feasibility, rapid postoperative recovery and few complications. Both groups gave comparable results in terms of lymph node dissection and short-term survival.