Anesthesia management of a patient with claustrophobia undergoing surgery for rhegmatogenous retinal detachment: A case report.

INTRODUCTION: Claustrophobia is a form of phobic anxiety disorder characterized by panic attacks. Anesthesia in patients with claustrophobia poses a challenge because these patients reject all treatments in an enclosed space. When such patients are treated in uncomfortably enclosed environments, it can cause mental distress and even sudden psychiatric death. CASE PRESENTATION: We report the case of a 55-year-old man with severe anxiety disorder and claustrophobia who required anesthesia for the surgical treatment of rhegmatogenous retinal detachment. This patient had a history of severe anxiety and claustrophobia for more than 40 years, without having received any treatment for the condition. The patient had failed to tolerate multiple chamber surgeries. Following multidisciplinary discussion, the patient's surgery was performed under general anesthesia in the operating room after the patient underwent induction of anesthesia outside the operating room. CONCLUSIONS: This case report shows that patients with claustrophobia need to be provided a comfortable environment for induction and awakening from anesthesia.

Performance of Active-Quenching SPAD Array Based on the Tri-State Gates of FPGA and Packaged with Bare Chip Stacking.

The performance of an active-quenching single-photon avalanche diode (SPAD) array that is based on the tri-state gates of a field programmable gate array (FPGA) is presented. The array is implemented by stacking a bare 4 × 4 N-on-P SPAD array on a bare FPGA die, and the electrodes of the SPAD pixels and the I/O ports of the FPGA are connected through wire bonding within the same package. The active quenching action on each SPAD pixel is performed by using the properties of the tri-state gates of the FPGA. Digital signal processing, such as pulse counters, data encoders, and command interactions, is also performed by using the same FPGA. The breakdown voltage of the SPAD pixels, with an active area of 60 µm × 60 µm, is 47.2-48.0 V. When the device is reverse biased at a voltage of ~50.4 V, a response delay of ~50 ns, a dead time of 157 ns, a dark count rate of 2.44 kHz, and an afterpulsing probability of 6.9% are obtained. Its peak photon detection probability (PDP) reaches 17.0% at a peak wavelength of 760 nm and remains above 10% at 900 nm. This hybrid integrated SPAD array is reconfigurable and cost effective.

[Application of high frequency color Doppler ultrasonography combined with microvascular stapler in maxillofacial defect repair].

Objective:To evaluate the clinical application value of high frequency color Doppler ultrasound（HFCUS） combined with microvascular stapler in the repair of oral and maxillofacial defects with the anterolateral thigh perforator flap. Method:Forty maxillofacial malignant tumor patients were divided into HFCUS+stapler group（23 cases） and control group（17 cases）. All of cases used anterolateral thigh flap without fascia lata to repair the soft tissue defect in the operative area. One artery and two veins were anastomosed during the operation. The flaps were harvested from 6.0 cm×7.0 cm to 10.0 cm×12.0 cm, and the donor sites were closed and sutured at the same time. In group HFCUS+stapler, HFCUS was used to locate the perforating vessels and mark the location on the body surface the operation, and the vein was anastomosed intraoperatively with a stapler. In the control group, only iliac patella line was fixed before operation, and the vein was manually sutured during operation. The clinical data of 2 groups was evaluated by comparing the time consumption of flap harvest, the vascular anastomosis, the incidence of postoperative venous crisis, and the long-term survival rate of flap. Result:In the HFCUS+stapler group, a total of 27 perforators were found before the operation, 24 perforators within 1.0 cm from the preoperative marker were actually detected during the operation, and the remaining 3 perforators were about 1.7 cm, 2.0 cm and 2.5 cm from the marker respectively, with an accuracy rate of 88.9%. HFCUS+stapler group used （63.17±7.80） min to harvest the flap, while the control group used （85.47±7.41） min HFCUS+stapler group took significantly less time than the control group（P<0.001）. The arterial anastomat time in the HFCUS+stapler group was （9.48±1.20） min and it was （9.18±1.13） min in the control group. The difference between the two groups was not statistically significant（P=0.426）. The total anastomosis time of the two veins was （14.87±2.62） min in the HFCUS+stapler group and （33.06±3.86） min in the control group. The HFCUS+stapler group had significantly less anastomosing time than the control group（P<0.001）. In HFCUS+stapler group, no arteriovenous crisis occurred after operation, and all flaps survived well 15 days after operation. In the control group, 2 cases had venous crisis after operation（P=0.091）. Conclusion:HFCUS combined with iliac patellar line can improve the accuracy of anatomical perforated vessels, reduce the time of flap harvesting, and reduce the possibility of accidental injury of perforated vessels. The use of microvascular stapler for vein anastomosis can reduce the operation time and improve the survival rate of flap. The combination of the two can significantly reduce the operation time of microsurgical repairing maxillofacial soft tissue defect, improve the operation quality, and has higher clinical application value.

Propofol-sparing effect of different concentrations of dexmedetomidine : Comparison of gender differences.

BACKGROUND: The pharmacodynamics of propofol are closely linked to gender. Dexmedetomidine can decrease propofol needs during propofol anesthesia. The aim of this study was to compare the gender differences on the calculated effect site median effective concentration (EC50) of propofol for loss of consciousness (LOC) after pretreatment with different concentrations of dexmedetomidine. METHODS: In this study 60 male and 60 female patients were randomly allocated to receive dexmedetomidine at target plasma concentrations of 0.0 ng/ml (0.0 group), 0.4 ng/ml (0.4 group), 0.6 ng/ml (0.6 group) and 0.8 ng/ml (0.8 group). Propofol was administered after dexmedetomidine had been intravenously infused for 15 min. The propofol infusion was targeted to provide an initial effect-site concentration of 1.0 µg/ml, followed by increments by 0.2 µg/ml when the effect-site concentration and target concentration of propofol were in equilibrium until LOC was established, where LOC was defined by the observer's assessment of alertness/sedation scale (OAA/S) score < 2. RESULTS: The calculated effect-site EC50 of propofol LOC was higher in males than in females in the 0.0, 0.4, 0.6, and 0.8 groups (2.43 vs. 2.17, 1.99 vs. 1.82, 1.72 vs. 1.56 and 1.50 vs. 1.32 µg/ml, respectively, all p < 0.05). The hypnotic interaction between dexmedetomidine and propofol could be described with an additive model of pharmacodynamic interaction. CONCLUSION: Gender significantly influenced the calculated effect-site EC50 of propofol for LOC after pretreatment with different concentrations of intravenous dexmedetomidine. It was concluded that an additive interaction could describe the results seen. Thus, gender has to be considered when these drugs are co-administered.

Systematic analysis of genes involved in oral cancer metastasis to lymph nodes.

Oral cancer remains a deadly disease worldwide. Lymph node metastasis and invasion is one of the causes of death from oral cancer. Elucidating the mechanism of oral cancer lymph node metastasis and identifying critical regulatory genes are important for the treatment of this disease. This study aimed to identify differentially expressed genes (gene signature) and pathways that contribute to oral cancer metastasis to lymph nodes. The GSE70604-associated study compared gene profiles in lymph nodes with metastasis of oral cancer to those of normal lymph nodes. The GSE2280-associated study compared gene profiles in primary tumor of oral cancer with lymph node metastasis to those in tumors without lymph node metastasis. There are 28 common differentially expressed genes (DEGs) showing consistent changes in both datasets in overlapping analysis. GO biological process and KEGG pathway analysis of these 28 DEGs identified the gene signature CCND1, JUN and SPP1, which are categorized as key regulatory genes involved in the focal adhesion pathway. Silencing expression of CCND1, JUN and SPP1 in the human oral cancer cell line OECM-1 confirmed that those genes play essential roles in oral cancer cell invasion. Analysis of clinical samples of oral cancer found a strong correlation of these genes with short survival, especially JUN expression associated with metastasis. Our study identified a unique gene signature - CCND1, JUN and SPP1 - which may be involved in oral cancer lymph node metastasis.

Pharmacokinetic and pharmacodynamics of intravenous dexmedetomidine in morbidly obese patients undergoing laparoscopic surgery.

BACKGROUND: This study was designed to investigate the pharmacokinetics and pharmacodynamics of dexmedetomidine in morbidly obese patients undergoing laparoscopic surgery. METHODS: Morbidly obese (body mass index ≥40 kg/m2) and normal weight patients scheduled for elective laparoscopic surgery were included (n = 8, each group). After baseline hemodynamic measurement, dexmedetomidine 1 µg/kg was administered over 10 min. General anesthesia was induced with propofol 1.5 mg/kg and fentanyl 4 µg/kg 20 min after completion of dexmedetomidine infusion; the lungs were mechanically ventilated after tracheal intubation. The pharmacokinetics of dexmedetomidine was analyzed by a noncompartment model. Hemodynamic data and peripheral oxygen saturation (SpO2) were measured up to 30 min after starting dexmedetomidine infusion. Sedation level was measured with the Observer's Assessment of Alertness/Sedation (OAA/S) scale. RESULTS: Peak plasma concentration, area under the curve to infinity, elimination half-life, and apparent volume of distribution were significantly larger in morbidly obese than in normal weight patients (3.75 ± 0.56 vs. 2.54 ± 0.32 µg/l, P < 0.001; 2174 ± 335 vs. 1594 ± 251 ng h/l, P < 0.001; 225 ± 55 vs. 158 ± 53 min, P = 0.02; 310 ± 63 vs. 164 ± 41 l, P < 0.001, respectively). Although clearance was also higher in obese patients than in normal body weight patients (58.6 ± 10.7 vs. 44.9 ± 9.0 l/h, P = 0.02), it was lower in obese patients than in normal body weight patients after normalization to total body weight (0.47 ± 0.07 vs. 0.64 ± 0.09 l/h/kg, P < 0.001). There were no differences in systolic or diastolic blood pressure or heart rate between the two groups within the 30 min. Sedation level was deeper and SpO2 was lower in morbidly obese than in normal weight patients. More patients in the morbidly obese patient group experienced deeper sedation after the start of the dexmedetomidine infusion (P < 0.05). CONCLUSION: The pharmacokinetics and pharmacodynamics of dexmedetomidine are significantly different in morbidly obese patients compared with normal weight patients. Level of sedation was significantly deeper, and oxygen saturation was significantly lower, in morbidly obese than in normal weight patients, probably resulting from higher plasma concentration after infusion of 1.0 µg/kg. CLINICAL TRIAL NUMBER, REGISTRY URL: ClinicalTrials.gov (NCT01864187), https://register.clinicaltrials.gov/prs/app/action/LoginUser?ts=1&cx=-jg9qo4 .

Continuous wound infusion of ropivacaine for the control of pain after thoracolumbar spinal surgery: a randomized clinical trial.

PURPOSE: A prospective randomized clinical trial was carried out to observe the analgesic efficacy of ropivacaine for postoperative pain following thoracolumbar spinal surgery. METHODS: Seventy-one patients with elective posterior thoracolumbar spinal surgery were randomly divided into two groups. Local group received 0.33 % ropivacaine by pump through the wound, and intravenous group received flurbiprofen axetil, pentazocine and palonosetron via intravenous pump. We evaluated the level of pain, the incidence of adverse reactions at 2, 4, 6, 12, 24, 36 and 48 h after operation, and the occurrence of chronic pain 3 months later. RESULTS: There were no significant differences in the pain level between the two groups. However, the incidence of nausea, vomiting and chronic pain was significantly lower in the local group. CONCLUSIONS: Our results showed that local infusion of ropivacaine achieved similar analgesic effects to intravenous delivery of analgesic drugs, but significantly reduced incidence of nausea, vomiting and chronic pain.

The overshoot and phenotypic equilibrium in characterizing cancer dynamics of reversible phenotypic plasticity.

The paradigm of phenotypic plasticity indicates reversible relations of different cancer cell phenotypes, which extends the cellular hierarchy proposed by the classical cancer stem cell (CSC) theory. Since it is still questionable if the phenotypic plasticity is a crucial improvement to the hierarchical model or just a minor extension to it, it is worthwhile to explore the dynamic behavior characterizing the reversible phenotypic plasticity. In this study we compare the hierarchical model and the reversible model in predicting the cell-state dynamics observed in biological experiments. Our results show that the hierarchical model shows significant disadvantages over the reversible model in describing both long-term stability (phenotypic equilibrium) and short-term transient dynamics (overshoot) in cancer cell populations. In a very specific case in which the total growth of population due to each cell type is identical, the hierarchical model predicts neither phenotypic equilibrium nor overshoot, whereas the reversible model succeeds in predicting both of them. Even though the performance of the hierarchical model can be improved by relaxing the specific assumption, its prediction to the phenotypic equilibrium strongly depends on a precondition that may be unrealistic in biological experiments. Moreover, it still does not show as rich dynamics as the reversible model in capturing the overshoots of both CSCs and non-CSCs. By comparison, it is more likely for the reversible model to correctly predict the stability of the phenotypic mixture and various types of overshoot behavior.

[Population pharmacokinetic modeling and evaluation of propofol from multiple centers].

In order to successfully develop the effective population pharmacokinetic model to predict the concentration of propofol administrated intravenously, the data including the concentrations across both distribution and elimination phases from five hospitals were analyzed using nonlinear mixed effect model (NONMEM). Three-compartment pharmacokinetic model was applied while the exponential model was used to describe the inter-individual variability and constant coefficient model to the intra-individual variability, accordingly. Covariate effect including the body weight on the parameter CL, V1, Q2, V2, Q3 and V3 were investigated. The performance of final model was assessed by Bootstrapping, goodness-of-fit and visual predictive checking (VPC). The context-sensitive half-times and the infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were simulated to six subpopulations. The results were as follows: the typical value of CL, V1, Q2, V2, Q3 and V3 were 0.965 x (1 + 0.401 x VESS) x (BW/59)(0.578) L x min(-1), 13.4 x (AGE/45)(-0.317) L, 0.659 x (1 + GENDER x 0.385) L x min(-1), 28.8 L, 0.575 x (1 + GENDER x 0.367) x (1 - 0.369 x VESS) L x min(-1) and 196 L respectively. Coefficients of the inter-individual variability of CL, V1, Q2, V2, Q3 and V3 were 29.2%, 46.9%, 35.2%, 40.4%, 67.0% and 49.9% respectively, and the coefficients of residual variability were 24.7%, 16.1% and 22.5%, the final model indicated a positive influence of a body weight on CL, and also that a negative correlation of age with V1. Q2 and Q3 in males were higher than those in females at 38.5% and 36.7%. The CL and Q3 were 40.1% increased and 36.9% decreased in arterial samples compared to those in venous samples. The determination coefficient of observations (DV)-individual predicted value (IPRED) by the final model was 0.91 which could predict the propofol concentration fairly well. The stability and the predictive performance were accepted by Bootstrapping, the goodness-of-fit and VPC. The context-sensitive half-times and infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were different obviously among the 6 sub-populations obviously. The three-compartment model with first-order elimination could describe the pharmacokinetics of propofol fairly well. The involved fixed effects are age, body weight, gender and sampling site. The simulations in 6 subpopulations were available in clinical anesthesia. The propofol anesthesia monitor care could be improved by individualization of pharmacokinetic parameter estimated from the final model.

[Research and application of microcontroller system for target controlled infusion].

This paper presents a microcontroller system for target controlled infusion according to pharmacodynamic parameters of intravenous anesthetics. It can control the depth of anesthesia by adjusting the level of plasma concentrations. The system has the advantages of high precision, extending power and easy manipulation. It has been used in the clinical anesthesia.