Renal Dialysis : Learning objectives & Introduction

Good day everybody. The topic that we are going to discuss today is dosing regimen in renal dialysis. First, let’s talk about the learning objectives. To define dialysis clearance that is to say dialysis. To determine dialysis clearance using the so called A-V difference method. And to determine dialysis clearance also by using dialysate concentration. To define dialyzability. And to assess which type of drug is dialyzable. And to describe pharmacokinetic factors that affect dialyzability of drugs. And to summarize the general principles for dosing adjustment in dialysis patient. Let’s talk about the relationship between ESRD and dialysis. As renal impairment progresses to the end stage, that is the end stage renal disease. Dialysis is used as a life support or sustaining treatment.

Because dialysis can be used to remove the uremic toxins. It also removes excessive water. Dialysis also removes electrolytes, which may need to be replenished. Dialysis treatment may interfere with drug therapy because of its drug clearing capacity. The relationship between ESRD and the uremic syndrome. Uremic toxins build up and that causes uremic syndrome. Including gastrointestinal such as nausea and vomiting. Hematological such as anemia. Peripheral neuropathy such as restless leg syndrome. Endocrine problem such as thyroid abnormality Metabolic function such as carbohydrate intolerance. Dermatological such as pruritus. Cardiovascular such as hypertension or congestive heart failure. Ocular for example the hypertensive retinopathy. Psychological such as depression and anxiety. And also neurological such as fatigue and headache. And as you look at this uremic syndrome.

You can imagine the average uremic patient or ESRD patient uses about 6 or 7 drugs to set the list. And whether these drugs are dialyzable or clear by the dialysis process would determine whether dosing adjustment is necessary for these drugs. Let’s talk about the diagnosis of end stage renal disease. First, the serum creatinine is higher. The urinary creatinine becomes lower. The urinary output, of course, is lower. And the urinary osmolality becomes higher. BUN is higher. Electrolyte are imbalanced. But the ultimate criteria for diagnosis is that creatinine clearance is less than 15 milliliters per minute per 1.73 meters square. And the value is calculated by the MDRD equation.

The treatment options for ESRD include hemodialysis, peritoneal dialysis, kidney transplantation and plus the conservative management.