Chronic gastritis/peptic ulcer

Chronic gastritis/peptic ulcer - pathogenesis

Peptic ulcers are created by an imbalance between the gastroduodenal mucosal defenses and the damaging forces that overcome such defenses. It is very well depicted above.

H.pylori does not invade the tissues but it causes intense local inflammation. It has flagella that allows it to move in the viscous mucous. Bacterial proteases and phospholipases break down the glycoprotein-lipid complexes in the gastric mucous, thus weakening the first line of mucosal defense. It also produces urease that breaks down endogenous urea to form ammonia. This causes the pH to increase locally. The H.pylori also has adhesins that make it bind to the cells and finally they elaborate toxins that cause further damage like metaplasia.

NSAIDs and aspirin are inhibitors of cyclooxygenase (COX). Thus they prevent the synthesis of prostaglandins. The latter is responsible for the promotion of mucin synthesis and vasodilation. In the absence of prostaglandins, the mucinous layer is depleted and the decreased vascular perfusion does not help in the regeneration of the damaged layer.

Ischaemia, shock and cigarette smoking also act by decreasing the blood flow.

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Hypokalemia - Potassium replacement calculation

DEFINITION Hypokalemia is defined as a serum potassium level of less than 3.5 mmol/L. Normal level= 3.5-5.5 mmol/L. It is encountered in >20% of patients. Patients are usually asymptomatic but severe arrhythmias and rhabdomyolysis can occur. Non-specific complaints include easy fatiguability and skeletal muscle weakness. The preferred method of replacement is via the oral route but at times this is not possible. The article below will give you an idea about how to calculate the amount of KCl to be given I.V. 1) Potassium deficit in mmol is calculated as given below: K deficit (mmol) = (K normal lower limit - K measured ) x kg body weight x 0.4 2) Daily potassium requirement is around 1 mmol/Kg body weight. 3) 13.4 mmol of potassium found in 1 g KCl . ( molecular weight KCl = 39.1 + 35.5 = 74.6) Suppose we get an asymptomatic patient of 70 Kg with a serum potassium level of 3.0 mmol/L and he is on nil by mouth but having an adequate diuresis, w

The plantar reflex - Babinski's sign

The plantar response is an important test to identify an upper motor neuron lesion. PROCEDURE To elicit it, the muscles of the lower limbs must be relaxed. The outer edge of the sole of the foot is stimulated by firmly scratching a blunt object like a key or a stick along it from the heel towards the little toe. This is what Joseph Babinski did in the year 1896. He described the 'great toe sign' that year and then in 1903 the 'toe abduction or fan sign'. Nowadays, a final medial movement across the sole of the metatarsus is also done. i.e. we start at the heel to the little toe and finally arcing to the big toe. The final arcing movement is absent in the original Babinski plantar response test. Babinski sign refers to a combination of 'the great toe sign' and the 'fan sign'. SIGNIFICANCE The normal response is plantar flexion of the toes (down going) and they are drawn together. More precisely, there is flexion of the big toe and addu

Differences between hyperemia and congestion

Hyperemia and congestion both indicate a local increased volume of blood in a particular tissue. Hyperemia is an active process that result from augmented blood flow due to arteriolar dilation (e.g. at sites of inflammation or in skeletal muscle during exercise). The affected tissue is redder than normal because of engorgement with oxygenated blood. Congestion, on the other hand, is a passive process resulting from impaired venous return out of a tissue. It may occur due to systemic causes like cardiac failure or a local cause like isolated venous obstruction. The tissue is cyanosed because the worsening congestion leads to accumulation of deoxygenated hemoglobin in the affected tissues.

Apgar scoring - table, mnemonic

INTRODUCTION The Apgar score was devised in 1952 by Dr Virginia Apgar (anesthesiologist) as a simple and repeatable method to quickly and summarily assess the health of newborn children immediately after birth. This helps to identify those requiring resuscitation and can also be used to predict survival in the neonatal period. MNEMONIC A mnemonic for learning purposes includes: A - Appearance (skin colour) P - Pulse (heart rate) G - Grimace (reflex irritability) A - Activity (muscle tone) R - Respiration Another mnemonic is also useful: How - Heart rate Ready - Respiration Is - Irritability This - Tone Child - Colour Apgar scoring is divided into 1 and 5-min scores. 1-MIN SCORE Sixty seconds after complete birth, the five parameters specified in the table above must be evaluated and scored. A total score of 10 indicates that the baby is in the best possible condition. A score between 0-3 me

Edema - Definition, pathophysiology, causes, clinical features

DEFINITION Edema is an abnormal presence of excessive fluid in the interstitial space. PATHOPHYSIOLOGY The movement of water and low molecular weight solutes such as salts between the intravascular and interstitial spaces is controlled primarily by the opposing effect of vascular hydrostatic pressure and plasma colloid osmotic pressure. Normally the outflow of fluid from the arteriolar end of the microcirculation into the interstitium is nearly balanced by inflow at the venular end. A small residual amount of fluid may be left in the interstitium and is drained by the lymphatic vessels, ultimately returning to the bloodstream via the thoracic duct. Either increased capillary pressure, diminished colloid osmotic pressure or inadequate lymphatic drainage can result in an abnormally increased interstitial fluid i.e. edema. An abnormal increase in interstitial fluid within tissues is called edema, while fluid collections in the different body cavities are variously

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