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This paper studies causes of scrap occurrence, wear and breakage of cutters during thread cutting of steel sleeves poured in Al die castings of motor car engine components. It was concluded that the reason for occurrence of problems with thread cutting of sleeves most probably should be attributed to the fact whether hardness value reaches 200 HB or over 250 HB. The most probable reason for over wear and consequently to breakage of cutters and scrap occurrence, although castings display top quality, lies in the fact that the internal diameter of sleeves frequently falls down under minimally allowed tolerances for threaded sleeves.

The influence of technological parameters on residual stresses in pressure die castings is analysed in this paper. In order for the residual stresses to be as low as possible the optimization of technological parameters is necessary. The centrally composed plan of experiment 24cs is used in the investigation. Technologically influencing parameters are changed according to the mentioned plan of experiment and they are: temperature of pouring, rate of die cavity filling with the melt, post pressure in already filled die and the casting cooling time along with the pouring system. [ABSTRACT FROM AUTHOR]

For a thorough understanding of the behaviour of foundry mould mixtures, a good knowledge of thermal properties of mould materials is needed. Laboratory determination of thermal conductivity of mould mixtures enables a better control over scabbing defects which are a major problem in green sand mould mixtures. A special instrument has been designed for that purpose and it is described in this work. [ABSTRACT FROM AUTHOR]

In the conditions of tribocorrosion wear, extending of parts lifetime could be achieved by using stainless steel, which is hardened to sufficiently high hardness. In the tribosystem bolt/ bushing shell/link plate of the bucket elevator transporter conveyor machine, the previously quenched and tempered martensitic stainless steel for bolts is hardened at ≈47 HRC and welded with the quenched and tempered high yield carbon steel for bolts. Additional material, based on Cr-Ni-Mo (18/8/6) is used. The microstructure and hardness of welded samples are tested. On the tensile tester, resistance of the welded joint is tested with a simulated experiment. Dimensional control of worn tribosystem elements was performed after six months of service. [ABSTRACT FROM AUTHOR]

The main role of therapy in Crohn's disease (CD) is to achieve long-term clinical remission, and to allow for normal growth and development of children. The immunomodulatory drugs used for the maintenance of remission in CD include thiopurines (azathioprine and 6-mercaptopurine) and methotrexate (MTX). Development of hepatosplenic T-cell lymphoma in some patients with inflammatory bowel disease, treated with thiopurines only or in combination with anti-tumor necrosis factor agents, resulted in a growing interest in the therapeutic application of MTX in children suffering from CD. This review summarizes the literature on the therapeutic role of MTX in children with CD. MTX is often administered as a second-line immunomodulator, and 1-year clinical remission was reported in 25-69% of children with CD after excluding for the use of thiopurines. Initial data on MTX effectiveness in mucosal healing, and as a first-line immunomodulator in pediatric patients with CD, are promising. A definite conclusion, however, may only be made on the basis of additional research with a larger number of subjects.

The main remit of the European Society for Paediatric Anaesthesiology (ESPA) Pain Committee is to improve the quality of pain management in children. The ESPA Pain Management Ladder is a clinical practice advisory based upon expert consensus to help to ensure a basic standard of perioperative pain management for all children. Further steps are suggested to improve pain management once a basic standard has been achieved. The guidance is grouped by the type of surgical procedure and layered to suggest basic, intermediate, and advanced pain management methods. The committee members are aware that there are marked differences in financial and personal resources in different institutions and countries and also considerable variations in the availability of analgesic drugs across Europe. We recommend that the guidance should be used as a framework to guide best practice., (© 2018 John Wiley & Sons Ltd.)

Moebius syndrome is a rare nonprogressive congenital neurological disorder with a wide range of severity and variability of symptoms. This diversity is a consequence of dysfunction of different cranial nerves (most often facial and abducens nerves), accompanying orofacial abnormalities, musculoskeletal malformations, congenital cardiac diseases, as well as specific associations of Moebius and other syndromes. The authors present anesthesia and airway management during the multiple tooth extraction surgery in a 10-year-old girl with Moebius syndrome associated with Poland and trigeminal trophic syndromes.

Children with Congenital Heart Disease (CHD) presenting for non-cardiac surgery have various physiological and functional abnormalities and thus pose great challenges to the anaesthesiologist. The principles of anaesthesia are to minimize pathophysiological changes which may upset the complex interaction between systemic and pulmonary vascular resistance. Knowledge of the specific cardiac anatomy, familiarity with the modifications of the cardiorespiratory physiology, the awareness of the potential risks of complications for each individual case are mandatory for the choice of the anaesthesia strategy for each patient. During the preoperative assessment, the risk-benefit ratio should be estimated and preoperative plan established in order to optimize the preoperative status. An anaesthesiologist must also understand pharmacology of drugs being used and should tailor anaesthetic management to the type of surgery. An interdisciplinary team approach is the cornerstone for the safe delivery of anaesthesia to this paediatric patient population. The team should comprise an anesthesiologist, a paediatric cardiologist, a surgeon, a cardio-surgeon and a neonatologist. This review is meant to explain the classification of congenital heart diseases and to equip the anaesthesiologist with the necessary information about preoperative assessment, anaesthesiology management, monitoring tools important for the safe non-cardiac surgery procedures as well as therapeutic strategies during the postoperative period.

Children with inherited neuromuscular diseases often require anaesthesia for diagnostic or therapy procedures. These patients have an increased risk of perioperative complications due to the nature of the disease and medications administered during anaesthesia. Many anaesthetics and muscle relaxants can aggravate the underlying disease and trigger life-threatening reactions (cardiorespiratory complications, malignant hyperthermia). Besides, the neuromuscular disorders are associated with atypical and undesirable responses to drugs used during anaesthesia and the perioperative period. The paper presents pathophysiological basis of inherited/genetic neuromuscular diseases and specific anaesthesiological problems. The recommendations are suggested with the aim to make the perioperative course in children optimally safe.

Background/aim: Reperfusion of previously ischemic tissue leads to injuries mediated by reactive oxygen species. The aim of the study was to investigate the effects of different anesthesia techniques on oxidative stress caused by tourniquet-induced ischemia-reperfusion (IR) injury during extremity operations at children's age., Methods: The study included 45 patients American Society of Anesthesiologists (ASA) classification I or II, 8 to 17 years of age, undergoing orthopedic procedures that required bloodless limb surgery. The children were randomized into three groups of 15 patients each: general inhalational anesthesia with sevoflurane (group S), total intravenous anesthesia with propofol (group T) and regional anesthesia (group R). Venous blood samples were obtained at four time points: before peripheral nerve block and induction of general anesthesia (baseline), 1 min before tourniquet release (BTR), 5 and 20 min after tourniquet release (ATR). Postischemic reperfusion injury was estimated by measurement of concentration of malondialdehyde (MDA) in plasma and erythrocytes as well as catalase (CAT) activity., Results: Plasma MDA concentration in the group S was significantly higher at 20 min ATR in comparison with the groups T and R (6.78 +/- 0.33 micromolL-1(-1) vs. 4.07 +/- 1.53 and 3.22 +/- 0.9. micromolL-1(-1), respectively). There was a significant difference in MDA concentration in erytrocythes between the groups S and T after 5 min of reperfusion (5.88 +/- 0.88 vs. 4.27 +/- 1.04 nmol/mlEr, p < 0.05). Although not statistically significant, CAT activity was slightly increased as compared to baseline in both groups S and R. In the group T, CAT activity decreased at all time points when compared with baseline, but the observed decrease was only statistically significant at BTR (34.70 +/- 9.27 vs. 39.69 +/- 12.91 UL-1, p < 0.05)., Conclusion: Continuous propofol infusion and regional anesthesia techniques attenuate lipid peroxidation and IR injury connected with tourniquet application in pediatric extremity surgery.

Neurotrauma is a leading cause of childhood mortality. Physicians are in a continuous search for means to decrease mortality and morbidity caused by head injury. Treatment of these patients requires familiarity with both cerebral pathophysiology and actions of anaesthetic agents on brain. Early treatment of hypotension and hypoventilation would cut mortality rate by at least one third. Prevention of increased intracranial pressure is the best treatment for head injury. Anaesthetist, neurosurgeon and radiologist should all be members of a team which can secure timely diagnosis and treatment of an injured child. Paying attention to every detail is of huge significance. Treatment of the child in a pediatric trauma center or an accident and emergencies center for adults with both personnel and equipment capable for handling paediatric patients offers greater probability of survival.

Introduction: Immunosuppressive effects of general anaesthesia and surgery could have unexpected consequences in a child with recent infection. The incidence of myocarditis in childhood is unknown., Case Outline: During general anaesthesia for inguinal hernia repair, a seven-year-old boy suddenly developed heart failure. Clinical presentation included hypotension, pulmonary oedema, drop in haemoglobin oxygen saturation, ST segment elevation and premature ventricular contractions. Haemodynamic stability and adequate oxygenation were achieved with dopamine and furosemide. Preoperative history, physical examination and complete blood count were unremarkable. Moderate cardiomegaly and pulmonary oedema were present on chest radiography. Diminished left ventricular contractility found on echocardiography increased troponin I and CK-MB levels suggested myocardial injury. Increased C-reactive protein with lymphocytosis suggested inflammation as its cause. Parents failed to report rubella 10 days before the operation. A clinical diagnosis of myocarditis as a complication of rubella was based on increased titer of IgM to rubella. With intravenous immunoglobulin, corticosteroids and symptomatic treatment for heart failure, his condition improved and ejection fraction reached 68% one month after operation., Conclusion: In future, we need protocols with instructions for paediatric patients undergoing elective surgery and anaesthesia after viral infections.

Introduction: Most children undergoing surgery can benefit from regional anaesthetic techniques, either as the sole anaesthetic regimen or, as usual in paediatric practice, in combination with general anaesthesia. The use of peripheral nerve blocks (PNBs) in paediatric anaesthesia is an effective way to decrease the side-effects and complications associated with central blocks. In spite of their many advantages, including easy performance end efficacy, peripheral nerve blocks are still underused., Objective: This article discusses a general approach to PNBs in children and provides data concerning the practice of this regional technique in different age groups., Methods: Data from 1,650 procedures were prospectively collected during the period from March 1, 2007 to February 29, 2008. The type of PNB, if any, as well as the patient age were noted. Our patients were divided into four groups: 0-3 years, 4-7 years, 8-12 years and 13-18 years., Results: During the investigated period, PNBs as a sole technique or in anaesthetized children were performed in 7.45% of cases. Ilioinguinal/iliohypogastric nerve block and penile block were the most common (70% of all PNBs) distributed mainly among the children between 4-7 years of age (p < 0.05). In older children, extremity PNBs predominate in regard to other types of blocks. PNBs are most frequently performed under general anaesthesia (85%), so the perineural approach requires a safe technique to avoid nerve damage., Conclusion: The observed differences in PNB usage seem to be related to patient age and correlate with common pathology and also with technical availability of PNB performance.

Among advances in medicine during the past 150 years, certainly the introduction of surgical anesthesia must be considered the greatest gifts of medical profession to mankind, especially to children. Pediatric anesthesia has progressed rapidly throughout the years. Since the first recorded case of pediatric anesthesia in 1842 to the latest advancement in training, technology, medicine and equipment in the last decades of this century, many historic moments have been following each other. Throughout the first decades of 20th century, most physicians treated children as miniature adults. It is believed that the development of modern pediatric anesthesia started in 1930. To offer a historic perspective, the evolution of new field through its rapid growth was divided into two chronologic categories: first (1930-1950) and second (1950-present). During the first period (1930-1950), the anesthesia techniques and equipment adjusted to different children's age were developed. In the second, together with further technique and equipment refinement, modern anesthetics and vital system surveillance (monitoring) were introduced into everyday practice. The keyto the advances in pediatric anesthesiology was difficulties leading to new inventions with consequent improvement of techniques and methods. This article reviews the origins and development of anesthesia for infants and children in the world and Serbia, emphasizing the contributions of many devoted physicians that represented the major force leading to inevitable evolution of pediatric anesthesia.

The American Committee, followed by the British, consisting of experts in various fields, in 1968 and 1976, respectively, reached the following consensus: "If a brain stem is dead, a brain is dead, if a brain is dead, a person is dead..." In the last few years, definition of brain death was necessary due to organ transplantation. Most of criteria verifying brain death do not include the specific determinants of brain death in children. This paper specifies the most up-to-date guidelines for diagnosis of brain death in children of various ages.