A retrospective analysis of obstetric hysterectomy in a tertiary center over one year

Background: Obstetric hysterectomy is a lifesaving procedure in a setting of life-threatening obstetrical hemorrhage. There is and increasing need of obstetric hysterectomy due to rising cases of caesarean sections and morbidly adherent placenta. We aimed to study the incidence, indications and fetomaternal outcome of obstetric hysterectomy. Various risk factors are discussed which may be helpful in reducing maternal and neonatal morbidity. Methods: A one year hospital based retrospective study involving detailed medical records of patients who underwent obstetric hysterectomy between 1st April 2022 and 31st march 2023. Results: The overall incidence of obstetric hysterectomy was 0.2% in this study with majority of patients in the 20-25-year age group, and patients who were 2nd and 3rd para comprised of the maximum number. The indication identified in this study were morbidly adherent placenta followed by atonic PPH and caesarean scar ectopic. The major risk factors noted were previous LSCS in 60% and morbidly adherent placenta in 53.3% patients. Of the 15 patients, 60% underwent total while 40% underwent subtotal hysterectomy. ICU admission, fever and coagulopathy were the leading post op complications. There was one case of maternal death noted and one case each of intrauterine death and perinatal mortality. Conclusions: Obstetric hysterectomy is the last resort to intractable bleeding and hence an important lifesaving procedure. The feto-maternal outcome depends on timely decision, surgical techniques and stringent post op monitoring of these patients

A clinical study on ectopic pregnancy in a tertiary care hospital over one year

Background: Ectopic pregnancy is a life threatening emergency in obstetrics presenting in the 1st trimester. The incidence is about 1% globally. We have aimed to study the incidence, presentation and management of ectopic pregnancy. Various risk factors were identified which may be helpful in reducing maternal mortality. Methods: A one year retrospective study involving detailed medical records of patients who underwent obstetric hysterectomy between 1st November 2022 and 31st October 2023. Results: The overall incidence of ectopic pregnancy was 0.8% in this study. The incidence was highest in 26-30 year age group (40%) followed by 21-25 year age group (36.4%). 95.2% cases presented with tubal ectopic while 2.4% each of cervical ectopic and caesarean scar ectopic pregnancies. LSCS was the most common risk factor associated with ectopic pregnancy, other risk factors included pelvic inflammatory disease in 33.3% cases, 29.5% patients with infertility treatment. 59% were ruptured ectopic pregnancies, 40% with unruptured ectopic pregnancy and 1% case of chronic ectopic. Multiple signs were seen in majority of patients including tachycardia, hypotension, abdominal tenderness, guarding and rigidity, vaginal forniceal fullness and tenderness. Management included laparotomy (58.8%), laparoscopy (31.7%), dilatation and evacuation (3.5%), medical management (3.5%) and hysterectomy (2.3%). No case of maternal mortality was noted. Conclusions: Ectopic pregnancy is still a major challenge in obstetrical practice because of its bizarre clinical presentation. Maternal outcome depends upon timely diagnosis and urgent management of such patients

Endoscopy in Neurosurgery

Introduction of endoscope was undoubtedly a great advancement in neurosurgery. It minimises trauma to the brain tissue and maximises the vision around the remote areas. The access to the ventricle and cisterns has become much easier. Development in optics, lenses, long and angled instruments made the endoscopy in neurosurgery very versatile. In this chapter, the introduction of the endoscopy in neurosurgery has been described along with its use in different branches of neurosurgery like neuro-oncology, hydrocephalus, skullbase, aneurysms, craniosynostosis etc. The details of some common and important operation have been described. Some relevant anatomy, which can be encountered in endoscopic approach, has been described which will be helpful to the readers. This chapter will also act as an eye-opener to the vast use of neuroendoscopy and will help broaden the horizon of trainee neurosurgeons, following which the further details can be sought in relevant books and literature. In brief, this chapter will tell us about the evolution to revolution of the neuroendoscopy

Orientational correlations and the effect of spatial gradients in the equilibrium steady state of hard rods in 2D : A study using deposition-evaporation kinetics

Deposition and evaporation of infinitely thin hard rods (needles) is studied in two dimensions using Monte Carlo simulations. The ratio of deposition to evaporation rates controls the equilibrium density of rods, and increasing it leads to an entropy-driven transition to a nematic phase in which both static and dynamical orientational correlation functions decay as power laws, with exponents varying continuously with deposition-evaporation rate ratio. Our results for the onset of the power-law phase agree with those for a conserved number of rods. At a coarse-grained level, the dynamics of the non-conserved angle field is described by the Edwards-Wilkinson equation. Predicted relations between the exponents of the quadrupolar and octupolar correlation functions are borne out by our numerical results. We explore the effects of spatial inhomogeneity in the deposition-evaporation ratio by simulations, entropy-based arguments and a study of the new terms introduced in the free energy. The primary effect is that needles tend to align along the local spatial gradient of the ratio. A uniform gradient thus induces a uniformly aligned state, as does a gradient which varies randomly in magnitude and sign, but acts only in one direction. Random variations of deposition-evaporation rates in both directions induce frustration, resulting in a state with glassy characteristics.Comment: modified version, Accepted for publication in Physical Review

Diffusion in periodic potentials with path integral hyperdynamics

We consider the diffusion of Brownian particles in one-dimensional periodic potentials as a test bench for the recently proposed stochastic path integral hyperdynamics (PIHD) scheme [Chen and Horing, J. Chem. Phys. 126, 224103 (2007)]. First, we consider the case where PIHD is used to enhance the transition rate of activated rare events. To this end, we study the diffusion of a single Brownian particle moving in a spatially periodic potential in the high-friction limit at low temperature. We demonstrate that the boost factor as compared to straight molecular dynamics (MD) has nontrivial behavior as a function of the bias force. Instead of growing monotonically with the bias, the boost attains an optimal maximum value due to increased error in the finite path sampling induced by the bias. We also observe that the PIHD method can be sensitive to the choice of numerical integration algorithm. As the second case, we consider parallel resampling of multiple bias force values in the case of a Brownian particle in a periodic potential subject to an external ac driving force. We confirm that there is no stochastic resonance in this system. However, while the PIHD method allows one to obtain data for multiple values of the ac bias, the boost with respect to MD remains modest due to the simplicity of the equation of motion in this case.Peer reviewe

Mechanisms of Enhanced Ionic Conduction at Interfaces in Ceramics

A large enhancement in the ionic conductivity of certain compounds occurs when the compound is produced as a composite material containing a finely-dispersed non-conductor such as SiO{sub 2} or Al{sub 2}O{sub 3}. This paper describes recent experiments which proposes that extended defects such as dislocations and grain boundaries, either resulting from or stabilized by the interface, are responsible for the enhancement. The ionic conductivities of LiI and CaF{sub 2} thin films grown on sapphire(0001) substrates were monitored in-situ during deposition as a function of film thickness and deposition conditions. LiI films grown at 27{degrees}C exhibited a region of enhanced conduction within 100 nm of the substrate and a lesser enhancement as the film thickness was increased further. This conduction enhancement was not stable but annealed out with a characteristic log(time) dependence. The observed annealing behavior was fit with a model based on dislocation motion which implies that the increase in conduction near the interface is due to extended defects generated during the growth process. CaF{sub 2} films grown at 200{degrees}C showed a behavior similar to the 27{degrees}C LiI films, with a region of thermally unstable enhanced conduction that occurs within 10 nm of the substrate. Amorphous Al{sub 2}O{sub 3} films deposited over the CaF{sub 2} layers created no additional enhancement but did increase the stability of the conduction, consistent with an extended defect model. Simultaneous deposition of CaF{sub 2} and Al{sub 2}O{sub 3} produced films consisting of very-fine-grained CaF{sub 2} and particles of amorphous Al{sub 2}O{sub 3} (5-10 nm grain and particle size) and a high defect density which was stable even well above the growth temperature. Measured conduction in the composite at 200{degrees}C was approximately 360 times that of bulk CaF{sub 2}

Simulation study of random sequential adsorption of mixtures on a triangular lattice

Random sequential adsorption of binary mixtures of extended objects on a two-dimensional triangular lattice is studied numerically by means of Monte Carlo simulations. The depositing objects are formed by self-avoiding random walks on the lattice. We concentrate here on the influence of the symmetry properties of the shapes on the kinetics of the deposition processes in two-component mixtures. Approach to the jamming limit in the case of mixtures is found to be exponential, of the form: $\theta(t) \sim \theta_{jam}-\Delta\theta \exp (-t/\sigma),$ and the values of the parameter $\sigma$ are determined by the order of symmetry of the less symmetric object in the mixture. Depending on the local geometry of the objects making the mixture, jamming coverage of a mixture can be either greater than both single-component jamming coverages or it can be in between these values. Results of the simulations for various fractional concentrations of the objects in the mixture are also presented.Comment: 11 figures, 2 table