Evaluation of the GCS-Pupils Score for PrOgnosis in trauMatic brAin injury- The COMA Study.

OBJECTIVES: Glasgow Coma Scale-Pupils (GCS-P) score has been found to be strongly related to in-hospital mortality in retrospective studies. We hypothesized that GCS-P would be better prognosticator than Glasgow Coma Scale (GCS) in patients with traumatic brain injury (TBI). METHODS: In this prospective, multicentric, observational study, GCS and GCS-P scores were noted in adult TBI patients at ICU admission. Demographic variables, relevant clinical history, clinical/radiological findings and ICU complications were also noted. Extended Glasgow Outcome scale was noted at hospital discharge and at 6 months post-injury. Logistic regression analysis was carried out to estimate the odds for poor outcome adjusted for covariates. Sensitivity, specificity, area under curve (AUC) and odds ratio are reported for poor outcome at estimated cutoff point. RESULTS: A total of 573 patients were included in this study. The predictive power for mortality, shown by the AUC, was 0.81 [95% CI: 0.77-0.85] for GCS and 0.81 [95% CI: 0.77-0.86] for GCS-P score, both being comparable. Similarly, the predictive ability for outcome at discharge and 6 months, the AUC-ROC for both GCS and GCS-P were comparable. CONCLUSIONS: GCS-P is a good predictor of mortality and poor outcome. However, the predictive performance of GCS and GCS-P for in-hospital mortality and functional outcome at discharge and at 6 months remains comparable.

Floquet Realization and Signatures of One-Dimensional Anyons in an Optical Lattice.

We propose a simple scheme for mimicking the physics of one-dimensional anyons in an optical-lattice experiment. It relies on a bosonic representation of the anyonic Hubbard model to be realized via lattice-shaking-induced resonant tunneling against potential offsets, which are created by a combination of a lattice tilt and strong on-site interactions. No lasers additional to those used for the creation of the optical lattice are required. We also discuss experimental signatures of the continuous interpolation between bosons and fermions when the statistical angle θ is varied from 0 to π. Whereas the real-space density of the bosonic atoms corresponds directly to that of the simulated anyonic model, this is not the case for the momentum distribution. Therefore, we propose to use Friedel oscillations in the density as a probe for continuous fermionization of the bosonic atoms.

Universal Scaling of Spectral Fluctuation Transitions for Interacting Chaotic Systems.

The statistical properties of interacting strongly chaotic systems are investigated for varying interaction strength. In order to model tunable entangling interactions between such systems, we introduce a new class of random matrix transition ensembles. The nearest-neighbor-spacing distribution shows a very sensitive transition from Poisson statistics to those of random matrix theory as the interaction increases. The transition is universal and depends on a single scaling parameter only. We derive the analytic relationship between the model parameters and those of a bipartite system, with explicit results for coupled kicked rotors, a dynamical systems paradigm for interacting chaotic systems. With this relationship the spectral fluctuations for both are in perfect agreement. An accurate approximation of the nearest-neighbor-spacing distribution as a function of the transition parameter is derived using perturbation theory.

Paediatric Intravenous Splint: A Cause of Pressure Injury during Neurosurgery in Prone Position.

Splint application avoids unwanted movement of limbs and kinking of intravenous catheters in infants, allowing free flow of intravenous fluids. However, if placed in contact with dependent surfaces during prone surgeries, they have the propensity to cause inadvertent pressure injuries. This occurs due to the weight of the limb and continuous friction and is augmented by a rise in the local temperature and perspiration. We wish to share our experience of such an unintentional injury caused by a paediatric intravenous splint.

Valsalva maneuver: Its implications in clinical neurosurgery.

Valsalva maneuver is associated with diverse physiological changes. These changes are used in various diagnostic and therapeutic clinical settings. Valsalva maneuver is also employed during various phases of neurosurgical procedures to achieve specific targets and confirm intraoperative findings. In this article, we attempt to describe the various clinical applications of the Valsalva maneuver within the realms of clinical neurosurgery. The associated complications of this act have also been discussed.

Contemporary social network sites: Relevance in anesthesiology teaching, training, and research.

OBJECTIVE: The phenomenal popularity of social networking sites has been used globally by medical professionals to boost professional associations and scientific developments. They have tremendous potential to forge professional liaisons, generate employment,upgrading skills and publicizing scientific achievements. We highlight the role of social networking mediums in influencing teaching, training and research in anaesthesiology. BACKGROUND: The growth of social networking sites have been prompted by the limitations of previous facilities in terms of ease of data and interface sharing and the amalgamation of audio visual aids on common platforms in the newer facilities. REVIEW: Contemporary social networking sites like Facebook, Twitter, Tumblr,Linkedn etc and their respective features based on anaesthesiology training or practice have been discussed. A host of advantages which these sites confer are also discussed. Likewise the potential pitfalls and drawbacks of these facilities have also been addressed. CONCLUSION: Social networking sites have immense potential for development of training and research in Anaesthesiology. However responsible and cautious utilization is advocated.

Sunburst quantum Ising model under interaction quench: Entanglement and role of initial state coherence.

We study the nonequilibrium dynamics of an isolated bipartite quantum system, the sunburst quantum Ising model, under interaction quench. The prequench limit of this model is two noninteracting integrable systems, namely a transverse Ising chain and finite number of isolated qubits. As a function of interaction strength, the spectral fluctuation property goes from Poisson to Wigner-Dyson statistics. We chose entanglement entropy as a probe to study the approach to thermalization or lack of it in postquench dynamics. In the near-integrable limit, as expected, the linear entropy displays oscillatory behavior, while in the chaotic limit it saturates. Along with the chaotic nature of the time evolution generator, we show the importance of the role played by the coherence of the initial state in deciding the nature of thermalization. We further show that these findings are general by replacing the Ising ring with a disordered XXZ model with disorder strength putting it in the many-body localized phase.

Evaluation of the Role of Preoperative Oral Amisulpride as Part of a Multimodal Antiemetic Prophylaxis Regime on Postoperative Nausea and Vomiting in Patients Undergoing Craniotomy: A Prospective, Double-Blind, Randomized, Placebo-controlled Study.

BACKGROUND: Patients undergoing craniotomy are at high risk for postoperative nausea and vomiting (PONV) despite the use of prophylactic antiemetics. We hypothesized that a single preoperative oral dose of amisulpride as part of a multimodal antiemetic regimen would decrease the incidence of PONV in patients undergoing craniotomy for intracranial tumor surgery. METHODS: Adult patients scheduled for elective craniotomy requiring general anesthesia were enrolled and randomized to receive either oral amisulpride 25 mg or placebo 2 hours before surgery in addition to our institution's usual antiemetic regimen. The primary outcome of the study was the incidence of nausea and/or vomiting during the first 24 hours postoperatively. Secondary outcomes included severity of nausea, use of rescue antiemetic medications, and treatment-related adverse events. RESULTS: A total of 100 patients were included in the analysis. More patients in the amisulpride group had no episodes of nausea (90% vs. 40%; P<0.001) and no episodes of vomiting (94% vs. 46%; P<0.001) compared with the placebo group. The severity of nausea was lower in the amisulpride group than in the control group in the first 4 hours after surgery (P<0.05), and fewer patients receiving amisulpride required rescue antiemetics (P<0.001). The incidence of treatment-related adverse events was similar between groups. CONCLUSIONS: A single preoperative oral dose of amisulpride 25 mg as a component of a multimodal antiemetic regimen decreased the incidence and severity of PONV in patients undergoing craniotomy for intracranial tumor surgery, with no adverse effects.

Comparison of Cardiac Indices Using Two Different Concentrations of Topical Adrenaline during Endoscopic Transsphenoidal Pituitary Surgery: A Prospective Randomized Observational Study.

Introduction Adrenaline-soaked wicks are often employed to decongest nasal mucosa during transsphenoidal pituitary surgeries to ensure proper hemostasis and visibility of the operating field. Considerable debate exists regarding the optimum concentration of adrenaline that strikes a balance between hemostasis as well as the hemodynamic side effects of adrenaline. This study assessed cardiac indices like cardiac output and cardiac index using a FloTrac Vigileo cardiac output monitor to compare two different concentrations of adrenaline used for topical instillation. Materials and Methods 60 adult patients undergoing transsphenoidal pituitary surgery were randomly assigned to receive cotton wicks soaked in adrenaline solution (either 1:100,000 or 1:200,000) for nasal decongestion. Following a standardized anesthetic regime, a FloTrac Vigileo cardiac output monitor was attached with the invasive arterial line for precise monitoring and recording of cardiac indices (cardiac output and cardiac index). Additionally, quality of surgical field (as reported by the operating surgeon) blood loss, incidences of adverse hemodynamic events, and rescue drug usage were recorded. Results No difference in cardiac outputs and cardiac indexes of the patients was observed during baseline to 55 minutes and at 80 minutes and onward, whereas difference rose to statistical significance at the time points of 60 minutes and 70 minutes ( p < 0.05). Other parameters like stroke volume, stroke volume variation, and hemodynamic parameters were similar. Quality of the surgical fields (as reported by the surgeon), intraoperative bleeding, incidences of adverse effects, and frequency of rescue drugs usage were similar. Conclusion Instillation of 1:100,000 dilution of adrenaline solution compared with 1:200,000 for nasal decongestion is associated with significant rise in cardiac output and cardiac index at 60 and 70 minutes of the surgery with similar blood loss and hemodynamic variables. Therefore, the lower concentration of adrenaline can be recommended for usage during transsphenoidal pituitary surgeries.

Pulse Pressure Variance (PPV)-Guided Fluid Management in Adult Patients Undergoing Supratentorial Tumor Surgeries: A Randomized Controlled Trial.

Objective Appropriate fluid management in neurosurgery is critical due to the risk of secondary brain injury. Determination of volume status is challenging with static variables being unreliable. Goal-directed fluid therapy with dynamic variables allows reliable determination of fluid responsiveness and promises better outcomes. We aimed to compare the intraoperative fluid requirement between conventional central venous pressure (CVP)-guided and pulse pressure variance (PPV)-guided fluid management in supratentorial tumor surgeries. Materials and Methods This prospective, randomized, double-blind, single-center trial was conducted with 72 adults undergoing supratentorial tumor surgery in a supine position. Patients were divided into two groups of 36 patients each receiving CVP- and PPV-guided fluid therapy. The CVP-guided group received boluses to target CVP greater than 8 mm Hg along with hourly replacement of intraoperative losses and maintenance fluids. The PPV-guided group received boluses to target PPV less than 13% in addition to maintenance fluids. Total intraoperative fluids administered and the incidence of hypotension was recorded along with the brain relaxation score. Postoperatively, serum lactate levels, periorbital and conjunctival edema, as well as postoperative nausea and vomiting were assessed. Statistical Analyses All statistical analyses were performed with Statistical Package for Social Sciences, version-20 (SPSS-20, IBM, Chicago, Illinois, United States). To compare the means between the two groups (CVP vs. PPV), independent samples t -test was used for normal distribution data and Mann-Whitney U test for nonnormal distribution data. The chi-square test or Fischer's exact test was used for categorical variables. Results The CVP group received significantly more intraoperative fluids than the PPV group (4,340 ± 1,010 vs. 3,540 ± 740 mL, p < 0.01). Incidence of hypotension was lower in the PPV group (4 [11.1%] vs. 0 [0%], p = 0.04). Brain relaxation scores, serum lactate levels, periorbital and conjunctival edema, and incidence of postoperative nausea and vomiting were comparable between the groups. Conclusion The requirement for intraoperative fluids was less in PPV-guided fluid management with better hemodynamic stability, adequate brain conditions, and no compromise of perfusion.

Quantum coherence controls the nature of equilibration and thermalization in coupled chaotic systems.

A bipartite system whose subsystems are fully quantum chaotic and coupled by a perturbative interaction with a tunable strength is a paradigmatic model for investigating how isolated quantum systems relax toward an equilibrium. It is found that quantum coherence of the initial product states in the energy eigenbasis of the subsystems-quantified by the off-diagonal elements of the subsystem density matrices-can be viewed as a resource for equilibration and thermalization as manifested by the entanglement generated. Results are given for four distinct perturbation strength regimes, the ultraweak, weak, intermediate, and strong regimes. For each, three types of tensor product states are considered for the initial state: uniform superpositions, random superpositions, and individual subsystem eigenstates. A universal timescale is identified involving the interaction strength parameter. In particular, maximally coherent initial product states (a form of uniform superpositions) thermalize under time evolution for any perturbation strength in spite of the fact that in the ultraweak perturbative regime the underlying eigenstates of the system have a tensor product structure and are not at all thermal-like; though the time taken to thermalize tends to infinity as the interaction vanishes. Moreover, it is shown that in the ultraweak regime the initial entanglement growth of the system whose initial states are maximally coherent is quadratic-in-time, in contrast to the widely observed linear behavior.

Effects of preoperative single dose Etoricoxib on postoperative pain and sleep after lumbar diskectomy: prospective randomized double blind controlled study.

BACKGROUND: Etoricoxib, a selective Cox-2 inhibitor has been found to be effective in the management of acute pain. This study evaluates the effect of preoperative use of oral Etoricoxib on post operative pain relief and sleep in patients undergoing single level diskectomy. METHODS: In this prospective, randomized, controlled study, forty four patient (ASA 1 & 2, age 18-60 years) scheduled to undergo single level lumber diskectomy were given either placebo (control group) or Etoricoxib 120 mg orally one hour before surgery. Post operatively fentanyl intravenous (IV) PCA pump was started. Visual analog score (VAS) was assessed at 0, 6, 12, 18 and 24 hours at rest and movement. Primary end point was total pain relief over 24 hours. Sleep overnight, total fentanyl consumption, incidence of nausea and vomiting, intra-operative blood loss and patient satisfaction were noted. RESULTS: Forty three patients completed the study. Reductions in VAS at rest and on movement were observed in the Etoricoxib group when compared with the Control group at all the intervals till 24 hours postoperatively, except on movement at 24 hours postoperative (P < 0.05). Total fentanyl consumption (microg/kg/hr) was higher in Control group (P = 0.007). More patients in Etoricoxib group had a contented facial expression (p = 0.003), relaxed body language (p = 0.00) and better sleep at night than control group (p = 0.0004). CONCLUSION: Single preoperative oral dose (120 mg) of Etoricoxib, given one hour before surgery, has significantly reduced the post operative pain at rest and movement and improved sleep in patients undergoing single level diskectomy without any side effects and with good patient satisfaction.

Comparison of Recovery Profiles of Patients Undergoing Endoscopic Lumbar Discectomy under Desflurane, Propofol, or Sevoflurane Anesthesia: A Randomized, Prospective, Clinical, Comparative Study.

Background Agents like propofol, sevoflurane, and desflurane having rapid revival of psychomotor and cognitive functions translating into reliable anesthetic recovery are chosen for day care procedures. This prospective randomized comparative study was undertaken to compare the psychomotor and cognitive functions of patients undergoing discectomy under different anesthetic strategies. Methods Seventy-five adult American Society of Anesthesiologists grade I and II patients being operated for endoscopic lumbar discectomy under different anesthetic regimens were enrolled and were subjected to Trieger Dot Test (TDT), Digit Symbol Substitution Test (DSST), and Mini-Mental State Examination (MMSE) preoperatively at specified intervals postoperatively. There emergence and early recovery times, complications, and satisfaction levels were also noted. Results No difference was found in the postoperative TDT and DSST and MMSE scores among the groups at all the time points (15 minutes, 3 minutes, 1 hour, 2 hours, 3 hours, and 4 hours). TDT and DSST demonstrated a tendency to return to baseline by 2nd and 3rd hour postoperatively. Emergence and early recovery times were earlier in the inhalation groups ( p 0.005 and 0.007, respectively). Time required to attain a Modified Aldrete Score of 9, complications, and observed side effects were similar among the groups. Conclusion Patients in the three groups had similar impairments in their psychomotor and cognitive functions which recovered at comparable time periods postoperatively. Emergence and early recovery were, however, faster in the desflurane group.

Impact of Postoperative ABG Analysis and ICU Weaning Protocol in Surgical Outcome of Atlanto-Axial Dislocation: It's not the Towering Sail, but the Unseen Wind that Moves the Ship.

Background: The outcome in patients of atlanto-axial dislocation (AAD) depends on multiple factors like preoperative optimization, intraoperative distractio and cord manipulation. Certain unfocussed factors such as respiratory reserve and compensatory acclimatization to hypoxia warrant consideration. Aims: The purpose of this study is to find the association of postoperative arterial blood gas (ABG) analysis and respiratory reserve in patients of AAD with clinical outcome. Study Design: We retrospectively analyzed the available records of patients, operated for AAD, at our institute (n = 66), from January 2014 to November 2018. Materials and Methods: Preoperative pulmonary function test (PFT) and the postoperative ABG analysis was noted. Timing of extubation, duration of intensive care unit (ICU) stays, and clinical outcomes (Nurick grade) were noted from the inpatient record and the last outpatient follow up. An independent t-test and analysis of variance were used to find significance. Results: In total, 41% (n = 27) patients had body mass index of less than 18.5, and 50% (n = 33) had breath holding time of less than 20 minutes. There was improvement in mean Nurick grade from 3.17 ± 0.8 to 2.76 ± 0.7 in follow up. A trend suggesting that patients with poor preoperative PFT has more ICU duration and worse outcome. In patients with mild acid-base disorders, extubation was possible within 24 hours. Out of 26 patients with ICU duration less than 2 days, 23 patients had "good" outcome, whereas ten out of 40 patients with ICU duration of more than or equal to 2 days had "bad" outcome (P = 0.00). Conclusion: Patients having moderate to severe primary or mixed acid-base disorder have a probability of re-intubation or delayed extubation. A strong correlation was seen with the novel grading system (grade >6 had worse outcome).

Nanoengineering InP Quantum Dot-Based Photoactive Biointerfaces for Optical Control of Neurons.

Light-activated biointerfaces provide a non-genetic route for effective control of neural activity. InP quantum dots (QDs) have a high potential for such biomedical applications due to their uniquely tunable electronic properties, photostability, toxic-heavy-metal-free content, heterostructuring, and solution-processing ability. However, the effect of QD nanostructure and biointerface architecture on the photoelectrical cellular interfacing remained unexplored. Here, we unravel the control of the photoelectrical response of InP QD-based biointerfaces via nanoengineering from QD to device-level. At QD level, thin ZnS shell growth (∼0.65 nm) enhances the current level of biointerfaces over an order of magnitude with respect to only InP core QDs. At device-level, band alignment engineering allows for the bidirectional photoelectrochemical current generation, which enables light-induced temporally precise and rapidly reversible action potential generation and hyperpolarization on primary hippocampal neurons. Our findings show that nanoengineering QD-based biointerfaces hold great promise for next-generation neurostimulation devices.

Efficient photocapacitors via ternary hybrid photovoltaic optimization for photostimulation of neurons.

Optoelectronic photoelectrodes based on capacitive charge-transfer offer an attractive route to develop safe and effective neuromodulators. Here, we demonstrate efficient optoelectronic photoelectrodes that are based on the incorporation of quantum dots (QDs) into poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-Phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction. We control the performance of the photoelectrode by the blend ratio, thickness, and nanomorphology of the ternary bulk heterojunction. The optimization led to a photocapacitor that has a photovoltage of 450 mV under a light intensity level of 20 mW.cm-2 and a responsivity of 99 mA/W corresponding to the most light-sensitive organic photoelectrode reported to date. The photocapacitor can facilitate action potential generation by hippocampal neurons via burst waveforms at an intensity level of 20 mW.cm-2. Therefore, the results point to an alternative direction in the engineering of safe and ultra-light-sensitive neural interfaces.

Entanglement production by interaction quenches of quantum chaotic subsystems.

The entanglement production in bipartite quantum systems is studied for initially unentangled product eigenstates of the subsystems, which are assumed to be quantum chaotic. Based on a perturbative computation of the Schmidt eigenvalues of the reduced density matrix, explicit expressions for the time-dependence of entanglement entropies, including the von Neumann entropy, are given. An appropriate rescaling of time and the entropies by their saturation values leads a universal curve, independent of the interaction. The extension to the nonperturbative regime is performed using a recursively embedded perturbation theory to produce the full transition and the saturation values. The analytical results are found to be in good agreement with numerical results for random matrix computations and a dynamical system given by a pair of coupled kicked rotors.

High-Performance, Large-Area, and Ecofriendly Luminescent Solar Concentrators Using Copper-Doped InP Quantum Dots.

Colloidal quantum dots (QDs) are promising building blocks for luminescent solar concentrators (LSCs). For their widespread use, they need to simultaneously satisfy non-toxic material content, low reabsorption, high photoluminescence quantum yield, and large-scale production. Here, copper doping of zinc carboxylate-passivated InP core and nano-engineering of ZnSe shell facilitated high in-device quantum efficiency of QDs over 80%, having well-matched spectral emission profile with the photo-response of silicon solar cells. The optimized QD-LSCs showed an optical quantum efficiency of 37% and an internal concentration factor of 4.7 for a 10 × 10-cm2 device area under solar illumination, which is comparable with the state-of-the-art LSCs based on cadmium-containing QDs and lead-containing perovskites. Synthesis of the copper-doped InP/ZnSe QDs in gram-scale and large-area deposition (3,000 cm2) onto commercial window glasses via doctor-blade technique showed their scalability for mass production. These results position InP-based QDs as a promising alternative for efficient solar energy harvesting.