Preoperative serum potassium changes in patients undergoing Open Heart Surgery under Cardiopulmonary Bypass: A Comparative study between two group of patients- one group of patients on long term preoperative diuretics and the other group not on diuretics

INTRODUCTION: The patients who undergo cardiac surgery in our hospital can be mainly divided into two groups. The first group of patients are who have coronary artery disease and the second group of patients are those with valvular heart disease. The first group of patients undergo coronary artery bypass grafting and the second group undergo valve repair or replacement. These patients will undergo these surgeries under cardiopulmonary bypass. They are in different class on the New York Heart Association’s physical status classification. Based on the severity of the disease and the symptoms, these patients are treated with different group of medications. As the disease advances these patients develop cardiac failure. When systolic heart failure occur, the heart can no more pump adequate amount of blood into the systemic circulation leading to symptoms of low cardic output or of the fluid overload to the heart . When diastolic dysfunction occur, the patients develop heart failure due to atrial hypertension. Congestive cardiac failure leads to the symptoms like easy fatiguability, dyspnea and congestion. The medical management of heart failure includes angiotensin converting enzyme inhibitors, diuretics, vasodilators and digitalis. Diuretics are used to relieve circulatory congestion. Symptoms improve as the pulmonary and peripheral edema are relieved. Diuretics reduce atrial and ventricular diastolic pressures thereby reducing the diastolic stress on the ventricular wall. This will help in preventing persistent cardiac distension and improve subendocardial perfusion. Chronic use of diuretics will lead to hypokalemia. So potassium supplementation is given in patients on chronic diuretics use. Potassium sparing diuretics helps in avoiding hypokalemia but they will not cause adequate natriuresis. Hypokalemia or hyperkalemia in the perioperative period cause cardiac conduction disturbances and they are not desirable. There are various factors in the perioperative period which can alter potassium homeostasis like the prescence of diabetic mellitus, hypertension, chronic renal failure, ischemic and valvular heart diseases, respiratory and metabolic acid-base disturbances, hypothermia, blood transfusion, dose and duration of the use of cardioplegia. The potassium homeostasis is maintained by giving potassium correction in the form of intravenous potassium in hypokalemia and by giving calcium, sodium bicarbonate, glucose-insulin infusion, nebulization with beta 2 agonists when hyperkalemia occurs. This is an observational study to study the role of preoperative use of diuretics in the incidence of altered serum potassium levels in the perioperative period. We compared two group of patients with one group on long term preoperative diuretic and the other group not on diuretics. This study helped us to understand whether diuretics played a role in the perioperative potassium homeostasis. AIMS AND OBJECTIVES: 1. To study the differences in the perioperative serum potassium changes between one group of patients on long term preoperative diuretics and the second group of patientswho were not on preoperative diuretics who underwent openheart surgery under cardiopulmonary bypass. 2. To compare the interventions needed to keep potassium homeostasis between the two groups. METHODOLOGY: Study Setting: The study was conducted in the Cardiothoracic operating suites and in the cardiothoracic intensive care units in Christian Medical College Hospital, Vellore. Study Population: 100 consecutive patients between 14 – 75 years who underwent cardiac surgeries during the 6 months study period in Christian Medical College Hospital, Vellore. Inclusion criteria: • Age < 14 years, • Chronic renal failure with serum creatinine > 1.6 mgms%. STUDY PERIOD: The study was conducted over a period of 6 months between July to December 2012. A pilot study was conducted prior to the commencement of the study. SAMPLE SIZE: 46. STUDY METHOD: The patients who fulfilled the inclusion criteria and gave consent were enrolled in the study. All medications that the patient was taking preoperatively were continued as per the routine schedule except ACE inhibitors. Tablet lorazepam and tablet omeprazole were given as premedication the night before and on the day of surgery. The preoperative comorbid conditions like diabetic mellitus, chronic renal failure, the medication taken like diuretics, ACE inhibitors, digoxin, Potassium supplements are all noted in the proforma. A baseline arterial blood gas (ABG) is done and the values entered in the proforma. The ABG is repeated once the patient is on the cardiopulmonary bypass circuit, before coming out of bypass circuit and after coming out of the bypass circuit. Any incidence of hypokalemia or hyperkalemia in noted along with the interventions made to keep the potassium levels normal. In hypokalemia, potassium chloride (kcl) is given and in hyperkalemia the treatment includes calcium, sodium bicarbonate, glucose insulin infusion. Any need for blood transfusion is noted as it may have an influence on serum potassium levels. The potassium rich cardioplegia is used to arrest the heart during cardiac surgery. The dose and the duration of cardioplegia is also noted. These patients are not extubated in the operation suite. They are shifted to the cardiothoracic intensive care unit (I C U)with endotracheal tube and electively ventilated for a day. The patient is followed in the for first two postoperative days in the ICU. In the ICU, arterial blood gas (ABG) is repeated every four to six hourly. Any event of hypokalemia or hyperkalemia along with the interventions needed to keep the the potassium level normal in noted. All patients received nebulizations with salbutamol and ipratropium bromide after extubation .We could enroll 100 patients in this study with 50 patients in the diuretic group and fifty I n the non-diuretic group. Once the adequate sample size has been achieved, all these datas were entered in the Epidata soft ware and exported into the Excel spreadsheet. STATISTICAL METHODS: 47. All the datas collected were analyzed using Generalized Estimating Equations. CONCLUSIONS: The observations of the study on ‘perioperative serum potassium changes in patients undergoing open heart surgery under cardiopulmonary bypass: A comparative study between two group of patients – one group of patients on long term preoperative diuretics and the other group not on diuretics’ are: 1. There is no significant statistical difference in the incidence of hypokalemia or hyperkalemia between the two group of patients. 2. A subgroup of patients who received preoperative oral potassium supplementation were found to be requiring 2 gms lesser potassium correction than in those who never received oral potassium in the preoperative period which is statistically significant with the p value of 0.000. 3. The patients who were diabetic and also on long term diuretic therapy required 1.3 gms lesser kcl to keep their potassium above 4 mEq/L than those who were not diabetic. This was found to be statistically significant with a p value of 0.010. 4. The role of other preoperative medications like ACE inhibitors, digoxin, did not have any statistical significance in causing a difference in serum potassium levels in both the groups. 5. The effects of parameters like haemoglobin, serum creatinine, serum bicarbonate, base excess, pH, Pco2 were all found to be clinically insignificant in affecting the perioperative potassium requirements in both the groups with the p values more than 0.7. 6. This study did not show any significant statistical difference in the perioperative requirement of sodium bicarbonate, calcium, magnesium ,glucose-insulin infusion and frusemide. 7. The role of cardioplegia and blood transfusion were also found to be statistically not significant in causing a change in serum potassium levels between both the groups

A Study on Role of Intramedullary Interlocking Nailing in the Complex Femoral Shaft Fractures: Short Term Outcome Analysis

INTRODUCTION: Fractures of the shaft of femur are a major cause of morbidity and mortality in patients who sustain high energy trauma. Morbidity arises from limb shortening, mal alignment, knee contractures and other complications of fracture. Mortality is infrequent but can result from an open wound, fat embolism, adult respiratory distress syndrome or multiple organ failure especially in the polytrauma patients. Both morbidity and mortality can be diminished by prompt reduction and internal fixation of the fracture (Robert A.,HansenT.et al. 1978 ). Restoration of alignment, rotation and length, preservation of the blood supply to aid union and rehabilitation of the patient is the goal of treatment. The type and location of the fracture, degree of comminution, the age of the patient, patients social, economic demands and other associated fractures may influence the method of treatment. Currently intramedullary, interlocking nailing is considered to be the treatment of choice for complex femoral shaft fractures. AIM: The aim of our study is to analysis the results of complex femoral shaft fractures treated by intramedullary interlocking nailing in our institution. MATERIALS AND METHODS: Between the oct 2006-nov2008., 20 cases of complex femoral fractures were treated with intramedullary interlocking in Govt General Hospital were included in our study.19 patients were male and one was female. Age group of these patients were ranging from 18-78 years. Inclusion Criteria - complex femoral fractures in adults. Exclusion Criteria - All Compound fractures. All Fractures in the paediatric and adolescent age group. Associated head injury, visceral injuries. Old fractures. All the complex femoral shaft fractures were examined throughly to look for associated injuries, neurovascular damage. Thorough examination of the ipsilateral hip and knee was performed. All the fractures were stabilized initially with thomas spilnt, plaster immobilization and pin traction. All patients were stabilized hemodyanamically with intravenous fluids, blood transfusion as required. RESULTS: In 10 patients with excellent results there was no shortening, mal alignment, no pain or swelling in the fracture site and movements of hip, knee were near normal. In 5 patients with good results had shortening of 1 cm and knee flexion of 120o. In 3 cases with fair results had limb shortening; and knee flexion of between 900-1200. In 2 cases of with poor results had limb shortening of 2 cm and knee stiffness. The range of movements of knee less than 90o. All the patients had fractures of both bone leg and that could be the cause of knee stiffness. CONCLUSION: Our study consists mostly of male patients in their active part of their life. So, there is a need for quick return of their daily routines. Intramedullary interlocking nailing for complex femoral fractures has been established world wide as the gold standard treatment because of its load sharing property, internal splinting, and rotational stability. These contribute the stable osteosynthesis. When the patients are taken up for surgery earlier, fracture reduction can be achieved by closed method and yield early fracture union, excellent functional outcome and prevention of complications. Early mobility, a low rate of complications and high incidence of union obtained in this study in majority of patients makes this technique more reliable

24,4,8-Trioxa-21-aza-1,3,6(1,2)-tri­benzena-2(2,3)-bicyclo­[3.3.0]octa­na­cyclo­octa­phane

The crystal structure of the title compound, C26H25NO3, was determined as part of an investigation of host–guest and electron donor–acceptor complexes. The oxazole and the pyrrole rings both adopt envelope conformations. The dihedral angle between the two benzene rings directly linked to the oxazole ring is 49.5 (1)°. The crystal structure is stabilized by a C—H⋯π inter­action

Reuse of textile effluent treatment plant sludge in building material

Abstract This study examines the potential reuse of textile effluent treatment plant (ETP) sludge in building materials. The physico-chemical and engineering properties of a composite textile sludge sample from the southern part of India have been studied. The tests were conducted as per Bureau of Indian Standards (BIS) specification codes to evaluate the suitability of the sludge for structural and non-structural application by partial replacement of up to 30% of cement. The cement-sludge samples failed to meet the required strength for structural applications. The strength and other properties met the Bureau of Indian Standards for non-structural materials such as flooring tiles, solid and pavement blocks, and bricks. Results generally meet most ASTM standards for nonstructural materials, except that the sludge-amended bricks do not meet the Grade NW brick standard. It is concluded that the substitution of textile ETP sludge for cement, up to a maximum of 30%, may be possible in the manufacturing of non-structural building materials. Detailed leachability and economic feasibility studies need to be carried out as the next step of research

Ethyl 2-[N-(2-Formyl­phen­yl)benzene­sulfonamido]acetate

In the title compound, C17H17NO5S, the N atom is sp 3-hybridized and the S atom has a distorted tetra­hedral configuration. The dihedral angle between the two aromatic rings is 30.0 (1)°, and that between the ethyl acetate group and the formyl­phenyl ring is 77.4 (1)°. The mol­ecules are linked into chains along [100] by C—H⋯O hydrogen bonds and the chains are linked via C—H⋯π inter­actions

2,5-Dimethyl-1-phenyl­sulfonyl-1H-pyrrole-3,4-dicarbaldehyde

In the title compound, C14H13NO4S, the mean planes of the pyrrole and phenyl rings form a dihedral angle of 88.7 (1)°. The aldehyde groups are slightly twisted from the pyrrole plane. In the crystal structure, mol­ecules are linked into a three-dimensional framework by C—H⋯O hydrogen bonds

A multi-omics longitudinal study of the murine retinal response to chronic low-dose irradiation and simulated microgravity

The space environment includes unique hazards like radiation and microgravity which can adversely affect biological systems. We assessed a multi-omics NASA GeneLab dataset where mice were hindlimb unloaded and/or gamma irradiated for 21 days followed by retinal analysis at 7 days, 1 month or 4 months post-exposure. We compared time-matched epigenomic and transcriptomic retinal profiles resulting in a total of 4178 differentially methylated loci or regions, and 457 differentially expressed genes. Highest correlation in methylation difference was seen across different conditions at the same time point. Nucleotide metabolism biological processes were enriched in all groups with activation at 1 month and suppression at 7 days and 4 months. Genes and processes related to Notch and Wnt signaling showed alterations 4 months post-exposure. A total of 23 genes showed significant changes in methylation and expression compared to unexposed controls, including genes involved in retinal function and inflammatory response. This multi-omics analysis interrogates the epigenomic and transcriptomic impacts of radiation and hindlimb unloading on the retina in isolation and in combination and highlights important molecular mechanisms at different post-exposure stages

Contribution of Cystine-Glutamate Antiporters to the Psychotomimetic Effects of Phencyclidine

Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine–glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine–glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect that is blocked by N-acetylcysteine pretreatment. To determine the relevance of the above finding, we assessed social interaction and found that N-acetylcysteine reverses social withdrawal produced by repeated PCP. In a separate paradigm, acute PCP resulted in working memory deficits assessed using a discrete trial t-maze task, and this effect was also reversed by N-acetylcysteine pretreatment. The capacity of N-acetylcysteine to restore working memory was blocked by infusion of the cystine–glutamate antiporter inhibitor (S)-4-carboxyphenylglycine into the prefrontal cortex or systemic administration of the group II mGluR antagonist LY341495 indicating that the effects of N-acetylcysteine requires cystine–glutamate exchange and group II mGluR activation. Finally, protein levels from postmortem tissue obtained from schizophrenic patients revealed significant changes in the level of xCT, the active subunit for cystine–glutamate exchange, in the dorsolateral prefrontal cortex. These data advance cystine–glutamate antiporters as novel targets capable of reversing the psychotomimetic effects of PCP

Multiple Aggregates and Aggresomes of C-Terminal Truncated Human αA-Crystallins in Mammalian Cells and Protection by αB-Crystallin

Cleavage of 11 (αA162), 5 (αA168) and 1 (αA172) residues from the C-terminus of αA-crystallin creates structurally and functionally different proteins. The formation of these post-translationally modified αA-crystallins is enhanced in diabetes. In the present study, the fate of the truncated αA-crystallins expressed in living mammalian cells in the presence and absence of native αA- or αB-crystallin has been studied by laser scanning confocal microscopy (LSM).YFP tagged αAwt, αA162, αA168 and αA172, were individually transfected or co-transfected with CFP tagged αAwt or αBwt, expressed in HeLa cells and studied by LSM. Difference in protein aggregation was not caused by different level of α-crystallin expression because Western blotting results showed nearly same level of expression of the various α-crystallins. The FRET-acceptor photo-bleaching protocol was followed to study in situ protein-protein interaction. αA172 interacted with αAwt and αBwt better than αA168 and αA162, interaction of αBwt being two-fold stronger than that of αAwt. Furthermore, aggresomes were detected in cells individually expressing αA162 and αA168 constructs and co-expression with αBwt significantly sequestered the aggresomes. There was no sequestration of aggresomes with αAwt co-expression with the truncated constructs, αA162 and αA168. Double immunocytochemistry technique was used for co-localization of γ-tubulin with αA-crystallin to demonstrate the perinuclear aggregates were aggresomes.αA172 showed the strongest interaction with both αAwt and αBwt. Native αB-crystallin provided protection to partially unfolded truncated αA-crystallins whereas native αA-crystallin did not. Aggresomes were detected in cells expressing αA162 and αA168 and αBwt co-expression with these constructs diminished the aggresome formation. Co-localization of γ-tubulin in perinuclear aggregates validates for aggresomes

A highly efficient green synthesis of 1, 8-dioxo-octahydroxanthenes

SmCl3 (20 mol%) has been used as an efficient catalyst for reaction between aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione at 120°C to give 1,8-dioxo-octahydroxanthene derivatives in high yield. The same reaction in water, at room temperature gave only the open chain analogue of 1,8-dioxo-octahydroxanthene. Use of eco-friendly green Lewis acid, readily available catalyst and easy isolation of the product makes this a convenient method for the synthesis of either of the products