Amar Kumar Saha

Bio: Amar Kumar Saha is an academic researcher from Khulna Medical College. The author has contributed to research in topics: Surgical emergency & Meconium. The author has an hindex of 3, co-authored 12 publications receiving 33 citations.

Neonatal intestinal obstruction : patterns, problems and outcome

Abstract: Neonatal intestinal obstruction is the most common surgical emergency in newborn. Ideally neonatal surgery should be done in an organized neonatal surgical unit. This study was done mostly in general surgical setup in Khulna without any facility of NICU and TPN. The aim of this study was to detect the patterns of neonatal intestinal obstruction and to find out the problems and outcome of surgical treatment. This retrospective study was done between January 2008 and December 2010, in Khulna Medical College Hospital, Khulna Shishu Hospital and a private clinic in Khulna. A total of 205 neonates with intestinal obstruction were treated surgically. Babies of both sexes up to 28 days of age were included in this study. Common causes of neonatal intestinal obstruction were anorectal malformation (ARM), intestinal atresia, Hirschsprung's disease (HD), meconium ileus and malrotation of midgut. Male-female ratio was 1.6:1 and about 13% was premature. Out of 205 neonates, there were ARM-73, HD-47, meconium ileus-38, intestinal atresia-29, malrotation-13 and others-5. Total 172 (84%) survived. Those were ARM (94%), Hirschsprung's disease (91%), meconium ileus (79%), intestinal atresia (55%), malrotation of gut (85%) and others (40%). Overall mortality after initial surgical treatment was 16%. Prognosis of surgical treatment depends on early intervention, expert anaesthesia, associated anomaly and complication, gentle handling of delicate tissue and intensive postoperative management. Medical practitioners were the first attending physician in most instances. So both physicians and surgeons have a contributing role in reducing mortality. DOI: http://dx.doi.org/10.3329/bmjk.v45i1-2.13638 Bang Med J (Khulna) 2012; 45 : 6-10

Processing of Tungsten Alloy Scrap for the Recovery of Tungsten Metal

Abstract: Penetrators usedfordefence purposes are prepared by po wder metallurgical technique. The material contains 90% tungsten along with other minor constituents such as iron, nickel, cobalt, chromium, aluminium etc. During the manufacturing process, three forms of scraps are generated whichare, powder, turnings and defective solid. Since the major constituents of the scrap is the costly tungsten metal, attempts were made to recover the metal by four different methods which are described in this paper. Electro-leaching of turnings in a diaphragm cell using chloride electrolyte bath was tried to remove minor elements. The purity of tungsten achieved in thisprocess was 99.9%. In the soda roasting - leaching process of powderliurning scraps, sodium tungstate of 99.85% purity was obtained with 90% yield. Attempt was also made to remove the impurities by acid leaching. 99.8% pure tungsten with 99% yield was achieved by acid leaching. Fine gravity separation and high intensity magnetic separation techniques were also adopted to enhance the tungsten value from the powder scrap, which produced the concentrate containing 96.2% tungsten.

Effect of intralesional bleomycin as an alternative therapy for cystic hygroma

Abstract: Cystic hygroma is a congenital malformation of the lymphatic system. Surgical excision is the treatment of choice, but injection of a sclerosing agent into the cyst is an alternative procedure. The aim of this study was to review the efficacy of intralesional bleomycin injection in cystic hygroma. This study was carried out in a private clinic in Khulna over a period of 2 years on 7 patients. Bleomycin at a dosage of 0.4-0.6 mg/kg was injected into the cyst and repeated injection was given at an interval of 4-8 weeks. Clinical outcomes were reviewed and analyzed. Seven patients, 4 males and 3 females, aged between one month and 4 years were treated with intralesional bleomycin injections. Complete clinical resolution was obtained in 6 cases (86%). Mass reduction was noted in 1 (14%) patient. Adverse reactions including mild fever, local swelling, redness and pain at the site of injection occurred in 3 cases (43%). These reactions persisted for only a few days. Transient systemic side effect like vomiting noted in one patient. So intralesional bleomycin injection is a safe and effective alternative to the surgical treatment of cystic hygroma. DOI: http://dx.doi.org/10.3329/bmjk.v46i1-2.18233 Bang Med J (Khulna) 2013; 46 : 12-15

Recovery of nickel from the ammoniacal solution of chromite ore overburden by solvent extraction-electrowinning

Abstract: By the reduction roast-ammonia leach process, an unexploited oxidic resource viz., overburden of chromite ore mines of Orissa, India, was treated to solubilise nickel and cobalt metals. For the separation and recovery of nickel and cobalt from this solution, application of LIX84-an oxime based solvent has been explored with the aim of producing electrolytic nickel metal. The bench scale experiments were initially carried out in a kinetic vessel metal. The bench scale experiments were initially carried out in a kinetic vessel for the extraction and stripping etc. were optimised. Based on these actual leach solutions containing 5.0g/L Ni and 0.077 g/L Co. These experiments showed the feasibility of extracting nickel with 30% LIX84 in kerosene in three stages and stripping of the loaded nickel with electrolyte solution at pH in four stages. The nickel pregnant electrolyte obtained from the solvent extraction at pH 1.1 in four stages. The nickel pregnant electrolyte obtained from the solvent extraction (SX) stage was found suitable for producing metal by electrowinning (EW) in the closed-loop SX-EW operation. At 50 C the average energy consumption and current efficiency were found to be 4.54kWh/kg and 69.0% respectively. Results show the possibility of producing electrolytic nickel metal from the overburden material by roast-leach-SX-EW route.

Surgical Interventions for Congenital Anomalies

Abstract: Great strides have been made during the past 50 years in the diagnosis and management of congenital anomalies, once referred to as birth defects. Formally fatal conditions can now be treated with success rates exceeding 90 percent. Yet improvements in care have been largely limited to high-income countries (HICs), even though many anomalies can be cured with simple operations (Chirdan, Ngiloi, and Elhalaby 2012). If surgery is the neglected stepchild of global health (Farmer and Kim 2008), then pediatric surgery is the child not yet born.Improving the accessibility and quality of pediatric surgical care in low-income (LICs) and lower-middle-income countries (LMICs) has the potential to substantially reduce childhood mortality and lifelong disability. Data on congenital anomalies in these countries are sparse, including on the incidence (conservatively estimated at 3 percent to 6 percent [CDC 2012; Christianson, Howson, and Modell 2006]), country-specific differences in disease burden, and cost-effective interventions. These areas of knowledge must be developed to identify implementation and surveillance priorities, and to advocate for resources.This chapter briefly summarizes the growing body of knowledge on surgical congenital anomalies in LICs and LMICs, highlights prevalent anomalies that exemplify the unrealized promise of pediatric surgery, and concludes with crucial future steps to reduce the burden of disease.Chapter 21 addresses economic evaluation of cleft lip and palate repair.

Congenital diaphragmatic hernia.

Abstract: Full text is available as a scanned copy of the original print version.

A comprehensive review on recycling methods for cemented tungsten carbide scraps highlighting the electrochemical techniques

Abstract: The scraped and end-of-life tungsten carbide materials demand innovative recycling methods to recover valuable refractory and strategic metals like tungsten, cobalt, nickel etc. The efficient treatment of this material significantly benefits to economics as compared to its ore. Several methods based on pyrometallurgy or hydrometallurgy or their suitable combination have been explored. These methods encompass several unit operations tested at the laboratory as well as on the pilot scale. Some of the methods also matured into technology on a commercial scale. However, the demonstration at the pilot plant scale is towards the validation of the developed process. Each of the methods tested so far has its own pros and cons. For instance, the combination of pyro-hydrometallurgical process has some advantages over hydrometallurgical processes such as higher efficiency, lower costs, and a few industrial requirements, but it is energy-intensive and requires high capex. Besides, considerable attempts have been put into the development of the electrodissolution processes, recently. Several studies available through reports, research articles, and patents recommend a selective electro-dissolution process, which is flexible enough to recycle different varieties of WC scraps. Various electrolytes based on acidic (H2SO4, HCl, H3PO4, HNO3) and alkaline (NaOH and NH3) media worked well to dissolve the refractory metal. Several additives are often added as supporting agents to obviate the most common constraint in electrodissolution, i.e., passivation of the anode. This review particularly highlights the electrochemical methods for the recycling of WC materials along with other recycling methods in brief.