P-EGS26 Outcomes of Surgical Treatment for Perforated Peptic Ulcer in a non-Upper Gastrointestinal Surgery Centre

Background Perforated peptic ulcer (PPU) remains a common surgical emergency worldwide requiring surgical intervention. Although commonly performed, morbidity and mortality rate remained high. This study aimed to analyze the factors that contribute to the outcome of PPU surgery in a non-upper gastrointestinal surgery center in Malaysia. Methods Data were collected by retrospective review of all PPU surgeries done throughout the year 2020, looking into various preoperative, intraoperative, and postoperative details. Results In this study, we have a total of 24 PPU patients underwent surgery resulted in 7 (29.2%) deaths. Majority of our subjects were elderly (median age 65 years, IQR 48.5 – 73.0) with 4 (16%) being of ASA (American Society of Anesthesiologist) category 3 - 4. The most common cause of death was uncontrolled systemic infection in 4 patients (57.1%), followed by 2 (28.6%) fatal arrhythmia and 1 (14.3%) massive upper gastrointestinal bleed. Our analysis found that size of perforation ≥ 30mm (OR = 0.18, 95%CI 0.08 - 0.44), and postoperative complications (OR = 12.5, 95%CI 1.6 – 97.6) were significantly associated with a higher postoperative death. Low serum albumin level (mean 34.3 ± 9.1g/L), negative base excess level (mean -3.28 ± 4.89), and prolonged interval between admission and commencement of surgery (median 750 mins, IQR 258 – 2218) were all significantly associated with increased mortality post PPU surgeries. Conclusions This study highlighted to us various perioperative factors which could potentially be modifiable thus necessary measures can be taken in the future to ensure a better operative outcome of PPU surgery.

Abstract 191: Effects of Anesthetic Agents on Blood Parameters in Rats With Acute Hemorrhagic Shock

Background: Recent studies in our laboratory indicate that isoflurane (ISO) has protective properties including improved survival in rats with hemorrhagic shock compared to ketamine and xylazine (K/X) anesthesia. The effects of these two anesthetic agents upon blood counts, gases and chemistries in the setting of hemorrhagic shock is unknown. The purpose of the present study was to examine the effects of these two commonly used anesthetic regimens on blood parameters in rats with acute hemorrhagic shock. Methods and Results: Sprague Dawley rats (both genders) were anesthetized with either intraperitoneal K/X (90mg/kg and 10mg/kg; n=12) or with isoflurane (5% isoflurane induction and 2% maintenance in room air; n=12). Rats were intubated and ventilated with room air. After heparinization, hemorrhagic shock was induced by withdrawing blood to a fixed mean blood pressure of 30 mmHg for one hour and then shed blood was reinfused. Arterial blood samples were collected at 1 hour after resuscitation with shed blood. We found that K/X was associated with lower PH and lower level of standard bicarbonate concentration (SBC) and oxygen saturation (SO 2 %) and more negative base excess; and had a significantly elevated anion gap, potassium, sodium and chloride levels compared to isoflurane (Table). Platelet counts were preserved and there was less elevation of white blood cell (WBC) in ISO (Table). There were no significant differences in PO 2 , PCO 2 , hematocrit, hemoglobin, glucose and lactate levels between the two types of anesthesia. Conclusions: The anesthesia influenced the levels of blood counts, gases and chemistries in rats with acute hemorrhagic shock, favoring ISO over K/X. Blood parameters remained essentially normal in ISO group, which may help explain the protective role of ISO in hemorrhagic shock.

Local Negative Base Transform and Image Scrambling

Scrambling transform is an important tool for image encryption and hiding. A new class of scrambling algorithms is obtained by exploiting negative integer as the base of number representation to express the natural numbers. Unlike Arnold transform, the proposed scrambling transform is one-dimensional and nonlinear, and an image can be shuffled by using the proposed transform to rearrange the rows and columns of the image separately or to permute the pixels of the image after scanned into a sequence of pixels; it can be also applied to shuffle certain part region of an image. Firstly, the transformation algorithm for converting nonnegative integers in base B to the corresponding integers in base -B is given in this paper, which is the computational core of scrambling transform and the basis of studying scrambling transform. Then, the three kinds of transforms are introduced, that is, negative base transform (abbreviated as NBT), modular negative base transform (MNBT), and local negative base transform (LNBT) with three parameters, where NBT is an injection and MNBT a surjection and LNBT a bijection. The minimum transform periods of LNBT are calculated for some different values of the three parameters, and the algorithm for calculating the inverse transform of LNBT is given. The image scrambled by LBNT can be recovered by the transform period or the inverse transform. Numerical experiments show that LNBT is an efficient scrambling transform and a strong operation of confusing gray values of pixels in the application of image encryption. Therefore, the proposed transform is a novel tool for information hiding and encryption of two-dimensional image and one-dimensional audio.

Interdisciplinary therapeutic application of potassium citrate in internal diseases

Citrates share both metabolic and excretory role. Through Krebs-cycle conversion they stimulate blood alkalization with biochemical-hormonal effects depending from the accompanying cation. The excretory function covers inhibition of calcium oxalate (COM) and uric acid (UA) aggregation in urine, reduction of calciuria. Citriaturia depends on acid-base equilibrium, diet, accompanying diseases and their treatment. Hypocitriaturia is defined as excretion of less than 320 mg/24h. It is found in tubular acidosis t.1, in 76-87% cases of calcium stones, in 40% of UA stone disease, in 30% cases of kidney stones with osteopenia. Potassium citrate (K3Cit) reduces urinary COM saturation, has good citriaturic effect. K3Cit increases effectiveness of thiazide treatment of calcium stone disease with osteopenia. In metabolic syndrome COM and UA saturation raise much more than cytriaturia. A metabolic acidosis in t.2 diabetes (DM2) induces hypocytriaturia and raises a risk of UA stone disease. Growing-up body mass index reduces citriaturic effect of K3Cit. In DM2 K3Cit reduces stone morbidity, reverses negative base equilibrium and increases insulin sensitivity. High K3Cit doses increase general lumbar bone mass and reduce bone resorption activity. In chronic interstitial nephropathies K3Cit slow down GFR decline. Slow releasing formulas of K3Cit and other citrates in accordance to precise indications should be elements of therapeutic regimen of calcium (i.e.: COM) or UA stone diseases, metabolic syndrome, osteopenia and chronic (interstitial) nephropathies. Profits are limited by the hydration status of patient and his/her motivation to long lasting treatment. The interdisciplinary usefulness of K3Cit may improve cost/effect ratio of treatment.