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METABOLIC ALKALOSIS It is a metabolic condition in which the PH of tissue is elevated beyond the normal range (7.35-7.45) In chronic vomiting, loss of water + HCL(Hypochloremia) ↓ Dehydration ↓ GFR decreased and the activation of RAAS(renin angiotensin aldosterone system) ↓  increase aldosterone ↓ Hypokalemic hypochloremic metabolic alkalosis CAUSES: Congenital hypertropic pyloric stenosis Ca stomach Healed peptic ulcer disease TREATMENT: Normal saline(0.9%) - so it is saline/chloride responsive metabolic alkalosis but if still PH > 7.55 in spite of fluids give NH4CL (Ammonium chloride)  HYPOKALEMIC METABOLIC ALKALOSIS - CHLORIDE NON RESPONSIVE METABOLIC ALKALOSIS CAUSES :  Nephrotic syndrome protein losing enteropathy eg: celiac sprue CHF Cirrhosis TREATMENT: Spironolactone and restrict salt intake

METABOLIC ACIDOSIS It is a serious electrolyte disorder characterized by an imbalance in the body's acid - base balance CAUSES: (Mnemonic - KULT) K etoacidosis: DM/Starvation/alcoholic U remia : AKI/CKD/RAS(renal artery stenosis)/ATN(acute tubular necrosis) L actic acidosis : Type A: shock , CO poisoning Type B: DM/drugs- eg- phenformin,vancomycin Type D: short bowel syndrome,jejunoileal bypass surgery(carbohydrates fermentation:bacterial flora ferment and form D-lactate T oxins : Methyl alcohol : decrease alcohol dehydrogenase(antidote - fomepizole) ↓ formaldehyde formation occurs→retinal damage - blindness ↓ formic acid and H+ causes damage to BBB causing the encephalopathy Ethylene glycol (antifreeze agent) : consumption can cause precipitation of ca+ oxalate crystals and cause ATN TREATMENT: Fluid of choice: Ringer lactate sodium bicarbonate - if PH < 7.2,inspite of fluid resuscitation - give soda bicarbonates ...

HYPERMAGNESEMIA  It is an electrolyte disorder in which there is a high level of magnesium in the blood Death due to Asystole CAUSES: CKD - chronic kidney disease Eclampsia Mgso4 toxicity Antacids/Laxative abuse PATHOPHYSIOLOGY: Increase magnesium → inhibit PTH release -↓calcium→blood vessel relaxation neuromascilar excitability↓ - so reflexes decreased CLINICAL FEATURE: Shock - non responsive to vasopressors and IV fluid DTR↓ ,Respiratory rate↓,co2↓ urinary output↓ TREATMENT: Vigorous IV hydration Ca gluconate Hemodialysis

HYPOMAGNESEMIA It is an electrolyte disturbance in which there is a low level of magnesium normal level - 1.3 -2.1 mEq/L CAUSES: diarrohea, alcoholics Thiazides - inhibits TRPM6(transporter) which causes magnesium reabsorption Amphotericin B Aminoglycosides Renal wasting: Gitelman syndrome  PATHOPHYSIOLOGY: Decrease magnesium ￫ relaxation of blood vessel Decrease magnesium ￫ inhibit PTH release ￫ decrease calcium and increase neuromuscular excitability CLINICAL FEATURES: Muscle cramps HTN, HR↑, arrhythmia(Torsades de pointes) Tremors/nystagmus/athetosis WORK UP: Serum magnesium urine magnesium ECG: prolonged QT - Torsades de pointes TREATMENT: IM /IV MgSO4 / Mg oxide /watch DTRs

HYPERKALEMIA It is an elevated level potassium(k+) in blood(above 5.5mEq/L) Normal potassium level 3.5 - 5mmol/L (3.5 - 5 mEq/L) Potassium level >8.0 mEq causes diastolic arrest CAUSES: Pseudo hyperkalemia : fist clenching, narrow bore needle, cooling of sample, TLC↑, platelet↑, RBC↑ Acidosis,Trans-cellular shift CKD/AKI Aldosterone↓ - Addison disease, histoplasmosis, HIV, waterhouse frederickson syndrome Gordon syndrome- gain of  NACL cotransport WORKUP: Increase potassium ECG: a)Tall peaked T wave b)ST segment depressed c)P wave - wide, flat d)QRS widened TREATMENT: Antagonism: Ca gluconate (usually used),Ca chloride (best) Redistribution: Insulin drip with 50% dextrose,salbutamol nebulization Removal of potassium: Furosemide,Resin sodium polystyrene sulphonate, PATIROMER(potassium binding agent), ZS - 9(sodium zirconium cyclosilicate)

HYPOKALEMIA It is a low level of potassium(k ๋) in blood serum normal potassium level 3.5 - 5mmol/L Death can occur due to  respiratory muscle paralysis CAUSES: Decrease intake Alkalosis : Potassium shift into cells Sympathomimetics stimulation - trauma, thyrotoxic periodic paralysis, beta 2 agonist toxicity(salbutamol) Renal loss - excess aldosterone = conn's syndrome,bilateral adrenal hyperplasia, ascites , CHF                   - Barter's , Gitelman syndrome                                                                                                       - Salt wasting nephropathy                    ...

HYPERNATREMIA It is a high concentration of sodium in blood normal sodium level - 135 - 145 mEq/L. Hypernatremia is defined as a serum sodium level more than 145 mEq/L Dangerous Hyper sodium > 158 mEq/L leads to development of seizures in a patient. Treatment - Diluted fluids (5% dextrose or N/2(0.45%) in 5% dextrose) causes: Loss of water from body like in extremely debilitated old patients having extreme thirst Lactulose: osmotic diarrhea Mannitol (excess doses) Diabetes insipidus with loss of water INVESTIGATION: Urine osmolality If osmolality is < 250 mOsm/L in case of Diabetes insipidus with polydipsia and no access to water. so here water loss in body occurs If osmolality >400 mOsm/L in case of extreme sweating - In asymptomatic hypernatremia - liberal water intake - Volume of fluids correction in case of sodium↑ - 160mEq TBW(total body water) X sodium actual - 145/145               ...

HYPONATREMIA  Hyponatremia is a low sodium concentration in the blood It is generally defined as a sodium concentration of less than 135 mmol/L                  (135 mEq/L) , with severe hyponatremia being below 125mEq/L Affects plasma osmolality changes in plasma sodium levels will affects plasma osmolality that will cause fluid shift across the brain cells and cause life threatening seizures PLASMA OSMOLALITY =  2( sodium + potassium ) +BUN/2.8 + GLUCOSE/18 BUN = BLOOD UREA NITROGEN NORMAL PLASMA OSMOLALITY = 285 -295 mOsm/L URINE OSMOLALITY  = 100 - 900 mOsm/L.it usually fluctuates a lot and helps to maintain plasma osmolality in a narrow range of 10 mOsm/L Normal sodium - 135 -145 meq Mild Hypo sodium - 130 - 135 meq Moderate Hypo sodium - 125 - 135 meq severe hypo sodium - < 125 meq - high risk of causing the fluid shift across the brain predisposing - Life threatening seizures HYP...