Propofol-Bispectral Index (BIS) Electroencephalography (EEG) Pharmacokinetic-Pharmacodynamic Model in Patients With Post-Cerebral Hemorrhage Hydrocephalus.

Background. Titrating hypnotic agents for patients who suffer from a cerebral insult is a challenging task. To date there is no real gold standard to precisely quantify electroencephalography (EEG) response in a fashion that could be utilized for patients with post-cerebral hemorrhage hydrocephaly. While we must administer "as per usual" analgesics for noxious stimuli, we have to administer the hypnotic agents more "sparingly" due to lack of objective monitoring. Methods. We compared 15 adult post-cerebral hemorrhage hydrocephalus patients undergoing ventriculo-peritoneal shunt placement with 15 controls matched for gender and approximate age. We set propofol target controlled infusion estimated plasma concentrations (Cp) to gradually reach 4 µg/mL over 4 minutes. To precisely quantify post-cerebral hemorrhage mental dysfunction, we used electronically retrieved bispectral index (BIS) and propofol Cp data points to create individual inhibitory monophasic mathematical model for each patient that incorporates an independent hysteresis "lag" function. Results. In post-cerebral hemorrhage patients Cp-BIS curve, C50 (propofol concentration associated with inhibitory 50% BIS response) cutoff point was significantly shifted to the left by 39%. Whereas before infusion and at stable propofol 4 µg/mL aneurismal surgical sides ipsilateral (75 ± 13, 25 ± 9) and contralateral (73 ± 15, 27 ± 9) mean ± SD BIS values were significantly lower than ipsilateral (95 ± 3, 46 ± 12) and contralateral (94 ± 3, 46 ± 12) matched controls. Conclusions. Using BIS as surrogate marker of propofol hypnotic effect, BIS monitoring in patients with post-cerebral hemorrhage hydrocephaly showed a pattern of change and trend that was similar albeit 39% significantly lower than subjects without.

Comparison of the effects of general and local anesthesia in lumbar interlaminar endoscopic surgery.

BACKGROUND: Percutaneous endoscopic lumbar discectomy (PELD) with an interlaminar approach is a technique used to treat lumbar disc hernia. It has not yet been established whether general or local anesthesia (LA) is preferable for lumbar interlaminar endoscopic surgery. METHODS: Between October, 2012 and June, 2016, 60 patients were recruited and randomly divided into 2 groups: the general anesthesia (GA) group and the LA group. The patients' basic clinical data, intraoperative patient experience, Oswestry disability index (ODI), visual analog scale (VAS) score, and the postoperative patient satisfaction rate were assessed. RESULTS: Statistically significant differences were found between the two groups in operative time and length of hospital stay. There were no significant differences in postoperative ODI or VAS scores between the two groups during follow-up at 3, 6, and 12 months. One patient in the GA group sustained a nerve root injury intraoperatively. Two patients in the LA group suffered adverse reactions, as did six patients in the GA group. However, 50% of the patients expressed fear about undergoing the surgery with LA, while all patients felt they could undergo the same surgery with GA. CONCLUSIONS: General and LA are both suitable for use in lumbar interlaminar endoscopic surgery. However, GA makes a positive intraoperative surgical experience more likely for the patient.

Pharmacokinetics of Intranasally Administered Dexmedetomidine in Chinese Children.

Background: Intranasal application is a comfortable, effective, nearly non-invasive, and easy route of administration in children. To date, there is, however, only one pharmacokinetic study on intranasal dexmedetomidine in pediatric populations and none in Chinese children available. Therefore, this study aimed to characterize the pharmacokinetics of intranasally administered dexmedetomidine in Chinese children. Methods: Thirteen children aged 4 to 10 years undergoing surgery received 1 µg/kg dexmedetomidine intranasally. Arterial blood samples were drawn at various time points until 180 min after dose. Dexmedetomidine plasma concentrations were measured with high performance liquid chromatography (HPLC) and mass spectrometry. Pharmacokinetic modeling was performed by population analysis using linear compartment models with first-order absorption. Results: An average peak plasma concentration of 748 ± 30 pg/ml was achieved after 49.6 ± 7.2 min. The pharmacokinetics of dexmedetomidine was best described by a two-compartment model with first-order absorption and an allometric scaling with estimates standardized to 70-kg body weight. The population estimates (SE) per 70 kg bodyweight of the apparent pharmacokinetic parameters were clearance CL/F = 0.32 (0.02) L/min, central volume of distribution V1/F = 34.2 (4.9) L, intercompartmental clearance Q2/F = 10.0 (2.2) L/min, and peripheral volume of distribution V2/F = 34.9 (2.3) L. The estimated absorption rate constant was Ka = 0.038 (0.004) min-1. Conclusions: When compared with studies in Caucasians, Chinese children showed a similar time to peak plasma concentration after intranasal administration, but the achieved plasma concentrations were about three times higher. Possible reasons are differences in age, ethnicity, and mode of administration.

[Tumor-selective replication, cytotoxicity and GM-CSF production of oncolytic recombinant adenovirus in KH901 injection].

OBJECTIVE: To study the tumor-selective replication, cytotoxicity and GM-CSF production of the recombinant virus in KH901 injection used to infect the cells cultured in vitro. METHODS: A panel of tumor and normal cells was infected with recombinant adenovirus in KH901 and wild-type adenovirus type 5 at a MOI of 2 PPC, the cells were harvested at 72 hours after infection and made a titer after three cycles of freeze/thaw; A panel of tumor and normal cells was infected with recombinant adenovirus KH901 at MOI of 1 or 10 PPC. For 24 hours after infection the medium was harvested to determine the biological activity of GM-CSF; A panel of tumor and normal cells was infected with KH901 of recombinant adenovirus and wild-type adenovirus type 5 at MOIs of 0, 0.1, 1, 10, 100, and 1000 PPC. At 7 days after infection, cell viability was determined by the MTT assay, and ECso was determined too. RESULTS: The data showed that wild-type adenovirus type 5 replicated efficiently in and killed both the tumor and normal cells, however, the recombinant adenovirus in KH901 replicated hugely in tumor cells [(2526.4+/-136.8)-(2796.6+/-104.6) TCID50/cell), and produced significant amount of GM-CSF [(1177. 793 +/-6.62)-(3924.497+/-17.79) IU/(10(6) cell x 24h)] and killed the tumor cells [EC50: (0.31+/-0.06)-(0.19+/- 0.01) pfu/cell] while was replicating poorly in non-permissive human normal cells [(56.8+/-9.2)-(90.1+/-14.4) TCID50/ cell], and producing very small amount of GM-CSF [(13.397+/-0.82) IU/(10(6)cell x 24 h)] and attenuating human primary cells killed [EC50: (92.33 +/- 9.12)-(121.20 +/- 19.94) pfu/cell], with which there was statistically a significant difference between wild-type adenovirus type 5 and recombinant adenovirus in KH901 (P<0.05). CONCLUSION: In vitro studies show that the tumor-selective replication, cytotoxicity, GM-CSF production of recombinant adenovirus lead the injection KH901 containing the recombinant adenovirus, as oncolytic agent, to have a potential utility for the treatment of solid tumors.