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Non-valvular heart disease is an important cause of cardiac disease in pregnancy and presents a unique challenge to the anesthesiologist during labor and delivery. A keen understanding of the underlying pathophysiology, in addition to the altered physiology of pregnancy, is the key to managing such patients. Disease-specific goals of management may help preserve the hemodynamic and ventilatory parameters within an acceptable limit and a successful conduct of labor and postpartum period

Complete tracheal resection is extremely rare after blunt chest trauma. A high degree of suspicion is essential to identify these cases and early intervention is associated with better outcome. We report a patient with complete tracheal resection, in whom the airway was secured whilst the patient remained awake, breathing spontaneously under fibreoptic bronchoscopic guidance. As a precautionary measure, we had kept cardiopulmonary bypass set up in readiness. Anaesthetic management needed to be modified during repair of the trachea, by using total intravenous anaesthesia with propofol and rocuronium infusion and insertion of a separate endotracheal tube into the distal portion of the trachea whilst reconstruction of the trachea took place. The usual inhalational technique could not be used. The anaesthesiologist managing such a case should be aware of the difficulties during securing the airway and during repair of the trachea. Proper planning and keeping back-up plans ready helps in successful management of these patients.

Byline: Gaurab. Maitra, Ahsan. Ahmed, Amitava. Rudra, Ravi. Wankhede, Saikat. Sengupta, Tanmoy. Das Postoperative renal dysfunction is a relatively common and one of the serious complications of cardiac surgery. Though [...]

Byline: Saikat. Sengupta, Arpan. Guha, Amitava. Rudra, Gaurab. Maitra, Palas. Kumar, Kajari. Roy Critically ill patients who require prolonged intensive care support are at high risk of developing multiple organ [...]

A constitutive model capable of predicting material flow behavior with high precision is essential for optimizing secondary processing parameters through simulation techniques. In this study, the hot deformation behavior of aluminum 5083+10 wt pct SiC particulate composite was predicted using constitutive equations based on the modified Johnson-Cook (JC), modified Zerilli-Armstrong (ZA), and strain-compensated Arrhenius models. The models were established on the basis of the true stress-strain values obtained from an isothermal hot compression test conducted on the INSTRON 8801 universal tensile testing machine under a temperature range of 473 K to 773 K and strain rate of 0.01 to 10 s−1. The prediction ability of the modified models was compared by calculating the correlation coefficient (R), average absolute relative error, and relative error. All the models could precisely predict the hot flow behavior of the composite. The modified ZA model had the highest accuracy. The JC model required the least number of material constants and had the lowest calculation time, followed by the modified ZA and strain-compensated Arrhenius models. [ABSTRACT FROM AUTHOR]

In the present research, isothermal hot deformation behavior of aluminum 5083 alloy + 15 (wt.%) SiC composite was obtained through compression test on INSTRON 8801 universal tensile testing machine (UTM) under a wide temperature range of 473-773 K and strain rate range of 0.01-10 s−1. The experimental true stress-strain data were employed to establish constitutive equations based on modified Johnson-Cook (JC) model and modified Zerilli-Armstrong (ZA) model to predict the hot flow behavior of the composite. The flow stress values obtained from these two models were plotted against the experimental flow curves to check the accuracy of these models. Suitability of the models was evaluated by comparing correlation coefficient (R), average absolute relative error and relative errors of prediction. The results show that the hot flow stresses of the present material depend on temperature and strain rate significantly. Both the models give good description of the hot deformation behavior of the composite. The prediction accuracy is found to be higher for modified ZA model compared to modified JC model, though the number of materials constants involved and time needed to evaluate them to establish the model are lower for modified JC model. [ABSTRACT FROM AUTHOR]

Background: The Bispectral Index (BIS) helps in the assessment of the depth of hypnosis. N-methyl-D-aspartic acid antagonist, ketamine, has been used in various doses to decrease postoperative morphine consumption. The purpose of our study was to compare the effects of two different doses (0.5 mg/kg and 0.2 mg/kg) of ketamine on BIS values., Methods: Forty-five ASA I or II patients undergoing general anesthesia were included in this double-blind, prospective, control trial and randomly allocated into three groups. After induction of anesthesia and tracheal intubation, a propofol infusion was started and titrated to attain BIS values of around 40. After five minutes of stable BIS values and in the absence of any surgical stimulus, patients received either 0.5 mg/kg of ketamine (Group K1) or 0.2 mg/kg of ketamine (Group K2) or normal saline (Group N) as bolus intravenously. BIS values were recorded for the next 15 minutes, at five-minutes interval., Results: Mean BIS values were significantly increased in Group K1 (63.5) while Group K2 (42.0) failed to show any significant rise. BIS values in Group K2 were comparable to those in Group N., Conclusion: Thus, under stable propofol anesthesia, a bolus ofketamine 0.5 mg/kg increases BIS values while ketamine 0.2 mg/kg does not.

Major obstetric hemorrhage is an extremely challenging obstetric emergency associated with significant morbidity and mortality. Pharmacological treatment of uterine atony has not altered much in recent years apart from the increasing use ofmisoprostol, although controversy surrounds its advantages over other uterotonics. Placenta accreta is becoming more common, a sequel to the rising caesarean section rate. Interventional radiology may reduce blood loss in these cases. Uterine compression sutures, intrauterine tamponade balloons and cell salvage have been introduced in the last decade.