Comparison of pulse pressure variation, stroke volume variation, and plethysmographic variability index in pediatric patients undergoing craniotomy / 北京大学学报(医学版)

OBJECTIVE@#To compare well-known preload dynamic parameters intraoperatively including stroke volume variation (SVV), pulse pressure variation (PPV), and plethysmographic variability index (PVI) in children who underwent craniotomy for epileptogenic lesion excision.@*METHODS@#A total of 30 children aged 0 to 14 years undergoing craniotomy for intracranial epileptogenic lesion excision were enrolled. During surgery, we measured PPV, SVV (measured by the Flotrac/Vigileo device), and PVI (measured by the Masimo Radical-7 monitor) simultaneously and continuously. Preload dynamic parameter measurements were collected at predefined steps: after induction of anesthesia, during opening the skull, intraoperative electroencephalogram monitoring, excision of epileptogenic lesion, skull closure, at the end of the operation. After exclusion of outliers, agreement among SVV, PPV, and PVI was assessed using repeated measures of Bland-Altman approach. The 4-quadrant and polar plot techniques were used to assess the trending ability among the changes in the three parameters.@*RESULTS@#The mean SVV, PPV, and PVI were 8%±2%, 10%±3%, and 15%±7%, respectively during surgery. We analyzed a total of 834 paired measurements (3 to 8 data sets for each phase per patient). Repeated measures Bland-Altman analysis identified a bias of -2.3 and 95% confidence intervals between -1.9 and -2.7 (95% limits of agreement between -6.0 and 1.5) between PPV and SVV, showing significant correlation at all periods. The bias between PPV and PVI was -5.0 with 95% limits of agreement between -20.5 and 10.5, and that between SVV and PVI was -7.5 with 95% limits of agreement between -22.7 and 7.8, both not showing significant correlation. Reflected by 4-quadrant plots, the con-cordance rates showing the trending ability between the changes in PPV and SVV, PPV and PVI, SVV and PVI were 88.6%, 50.4%, and 50.1%, respectively. The concordance rate between PPV and SVV was higher (92.7%) in children aged less than 3 years compared with those aged 3 and more than 3 years. The mean angular bias, radial limits of agreement, and angular concordance rate in the polar analysis were not clinically acceptable in the changes between arterial pressure waveform-based parameters and volume-based PVI (PPV vs. PVI: angular mean bias 8.4°, angular concordance rate 29.9%; SVV vs. PVI: angular mean bias 2.4°, angular concordance rate 29.1%). There was a high concordance between the two arterial pressure waveform-based parameters reflected by the polar plot (angular mean bias -0.22°, angular concordance rate 86.6%).@*CONCLUSION@#PPV can be viewed as a surrogate for SVV, especially in children aged less than 3 years. The agreement between arterial pressure waveform-based preload parameters (PPV and SVV) and PVI is poor and these two should not be considered interchangeable. Attempt to combine PVI and PPV for improving the anesthesiologist's ability to monitor cardiac preload in major pediatric surgery is warranted.

Surgery for pediatric intractable epilepsy due to posterior quadrantic cortical dysplasia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical features and surgical strategy for pediatric intractable epilepsy due to posterior quadrantic cortical dysplasia and to assess the surgical outcomes.</p><p><b>METHODS</b>The clinical features and preoperative evaluation results of 14 children with intractable epilepsy due to posterior quadrantic cortical dysplasia were retrospectively analyzed. The localization values of video-electroencephalography and intraoperative monitoring and the indications, advantages and disadvantages of temporoparietooccipital disconnection were evaluated.</p><p><b>RESULTS</b>The 14 children had different seizure types, of which spasm was the most common one. The lesions of cortical dysplasia involved the central cerebral region in 2 cases. After temporoparietooccipital disconnection in 14 patients, 13 cases were seizure-free; only one case still had seizures, but the frequency dropped by more than 50%.</p><p><b>CONCLUSIONS</b>Temporoparietooccipital disconnection is a safe and effective surgical procedure for children with intractable epilepsy due to posterior quadrantic cortical dysplasia.</p>

A comparative study on intraoperative electrocorticography with long-term intracranial EEG for localizing epileptogenic zone / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss the localizing methods for epileptogenic zone with intraoperative electrocorticography (ECoG) by comparing it with long-term intracranial EEG.</p><p><b>METHODS</b>Twenty-two patients was enrolled, who received epilepsy surgeries consecutively in our institute since April 2005 to August 2006. All patients underwent intracranial electrode implantations with long-term video-EEG monitoring before the resective surgeries and the postoperative pathologies were all proved to be focal cortical dysplasia. The extra-operative and ECoG digital EEGs were statistically analyzed and compared with each other, including interictal epileptic discharge (IED) frequency, amplitude and their correlations with ictal discharge (ID).</p><p><b>RESULTS</b>In the long-term intracranial EEG, significant difference was found between IED frequency derived from ID onset verus none-onset electrodes (Z = 12.213, P < 0.001), ROC analysis showed that IED frequency is a moderately good indicator for ID, the area under the ROC curve was 0. 758 (95% CI, 0.707-0.810). There was significant difference in IED amplitude between ID and none-ID electrodes (Z = 11.765, P < 0.001). The IED frequency was significantly lower during ECoG than during long-term extra-operative monitoring (rho = 0.518, P = 0. 014). A significant positive correlation in the IED frequency pattern was found between intra-operative ECoG and extra-operative recording when the average IED frequency was over 3 spikes /min. In ECoG, the correlation of IED with ID was similar in the 'frequent' (> or = 10 spikes/min) and 'occasional' (3-10 spikes/min) groups and very different in the 'rare' (< or = C3 spikes/min) group (rho = 0.408, P = 0.147).</p><p><b>CONCLUSIONS</b>The IED from long-term EEG recording had moderate correlation in frequency and amplitude with ID position. IED frequency was usually decreased on ECoG when compared with long-term monitoring. However, ECoG could reliably reflect the IED pattern and the correlations between IED with ID in term of frequency and amplitude in the long-term EEG monitoring, when IED frequency exceeded 3 spikes/min. Under this circumstance, IED could be used for localizing the epileptogenic zone.</p>

Surgical treatment of lesional temporal lobe epilepsy / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss the presurgical evaluation and surgical treatment of lesional temporal lobe epilepsy (LTLE).</p><p><b>METHODS</b>We retrospectively studied the patients whose MRI or CT showed lesions on one of the temporal lobes among patients who underwent epilepsy surgeries in our institute. All patients were divided into satisfactory and unsatisfactory group according to outcomes after operation. The characteristics of the lesions, neurophysiological features and results of pathologies were analyzed statistically.</p><p><b>RESULT</b>Favorable surgical outcome was obtained in 24 patients, the satisfactory rate was 75%. The lesions of 17 patients were cortical malformations and the satisfactory rate of this group was 65%, which was less favorable than that of tumor group, (87%). 21 patients with their lesions located within the border of standard temporal lobectomy, had better surgical outcome than the others whose lesions were beyond the border (P<0.05). The satisfactory rate of 8 patients with lesions located within mesial structure of temporal lobe was no different compared with that of the others who had lesions outside the mesial structure (P>0.05). There were 19 patients who had consistency of the location of the lesion on MRI with the focal interictal epileptiform discharges on scalp EEG in satisfactory group, while there were only 3 patients in unsatisfactory group (P<0.05).</p><p><b>CONCLUSION</b>For a LTLE patient, epilepsy surgery should be the first choice to be considered. Careful presurgical studies of the lesion, including its location, pathological property and neurophysiological characteristics, were very helpful for improving the surgical outcome.</p>