Causes of hypotension during dialysis by aniqa atta

title; hypotension and causes of hypotension
this lecture will cover the hemodialysis related hypotension and causes of hypotension during dialysis. like cardiac related factors, idh related volume changes..

1. HYPOTENSION ANIQA ATTA BS: RENAL DIALYSIS TECHNOLOGY MPHIL: MOLECULAR BIOLOGY and genetics

2. Blood Pressure DEFINITION : Blood pressure is the pressure or force exerted by blood on the walls of blood vessels

3. Physiology of Heart

4. Hypotension Is a medical term used for low blood pressure less than 90/60mmHg

5. Intradialytic hypotension DEFINITION: A nadir (lowest) systolic blood pressure less than 90mmHg , a fall in systolic BP of 20 or 30mmhg Is associated with IDH related mortality Highest in patients with low pre-Dialysis patients This is a marker for cardiac stunning, structural and functional abnormality

6. Causes Of Intradialytic Hypotension 1. Volume related Large weight gain Short weekly dialysis time Excessively low target or dry weight 2. Inadequate vasoconstriction High dialysis solution temperature Autonomic neuropathy Anti hypertensive medication Eating during treatment Anemia

7. Causes of Intradialytic Hypotension 3. Cardiac factors Diastolic dysfunction 4. Uncommon causes Pericardial tamponade Myocardial infarction Occult hemorrhage Septicemia Dialyzer reaction Hemolysis Air embolism

8. IDH related to blood volume changes 1. Avoid large interdialytic weight gain: Emphasize on salt restriction …….. Effective in decreasing interdialytic weight gain Higher sodium intake …………. Poor outcome 2. Increasing weekly treatment time: By definition we can say, decrease the required UF rate (same weight loss, longer time) Weekly dialysis time for fluid removal is often treated on Mon, Wed, Fri, Sat

9. Cont …. KDOQI guidelines recommend treatment time not be reduce below 3 hours 3. Maintaining urinary volume: Amount of urine volume is subtracted, amount of fluid removed during dialysis Urine volume increase…….. Diuretics therapy

10. Cont …. 4. Choose target weight carefully: Dry weight: Is a weight without excess fluid 5. Use an appropriate dialysis solution sodium level: 2 hrs ….. Sodium level high Rest of time….. decrease it

11. Hypotension related to vasoconstriction: 1. Lower dialysis solution temperature When dialysis solution temperature is higher than normal arterial temperature cutaneous vasodilation occur allows heat to dissipate. This reduction in peripheral resistance predisposes to hypotension 35.5-36.5 degree centigrade is better initial choice Cool dialysis temperature causes patients discomfort when temp is below than euthermic values……. Shivering and chills

12. Continue… 2. Avoid intradialytic food ingestion in hypotension prone patients: Eating during dialysis can precipitate or accentuate a fall in blood pressure The effect is probably a result of dilation of resistance vessels in splanchnic bed which reduces TRP and splanchnic venous capacity The food effect on BP lasts at least 2 hours Patients who are prone to dialysis should avoid eating before and after dialysis

13. Cont … 3. Minimize tissue ischemia during dialysis: During hypotensive stress.. Resulting tissue ischemia causes…release of adenosine Adenosine blocks release of nor epinephrine from sympathetic nerve terminals and also has intrinsic vasodilator property Severe hypotension therefore a mplify itself:

14. HYPOTENSION ISCHEMIA ADENOSINE RELEASE IMPAIRED NOR EPINERHRINE RELEASE VASODIALATION HYPOTENSION

15. Cont … Transfusion is beneficial in anemic patients Nasal oxygen is another way to for limiting tissue ischemia and IDH

16. Hypotension related to cardiac factor 1. diastolic dysfunction: Stiff hypertrophied heart is especially prone to reduction in output when there is even minor reduction in filling pressure Common in dialysis patients owing to the effects of hypertension and coronary artery disease Using verapamil an antihypertensive drug to reduce IDH

17. Cont … 2. Heart rate and contractility Dialysis hypotension is associated with decrease cardiac filling a mechanism in which cardiac compensatory mechanism do little to increase output In some patients TRP may fall to temperature effects, food ingestion and tissue ischemia In this way cardiac compensatory mechanism can play a direct role in the development of hypotension

18. Cont … 3. dialysis solution calcium: Rage= 1.75mM Increase cardiac contractility Especially in patients with cardiac disease Higher level can causes vascular calcification