Mechanism of anti-hypertensive action of beta blockers

In current medical practice, beta blockers are classified into three classes

👄 Non-selective beta blockers (blocks both beta 1 and beta 2 receptors): 

            ACUTE EFFECT

                    Beta 1 blockade: 

                            👉 Decreased heart rate and decreased cardiac contractility

                            👉 Decreased cardiac output

                            👉 Systolic BP tends to decrease

                    Beta 2 blockade:

                            👉 Increased peripheral vascular resistance

                            👉 Diastolic BP tends to increase

               NET ACUTE EFFECT: No change in BP

                

               PROLONGED USE EFFECT:

                            👉 Decreased cardiac output

                            👉 Adaptation of resistance vessels to persistently reduced cardiac output

                            👉 Decrease in peripheral resistance

                            👉 Systolic BP decreases due to decreased cardiac contractility

                            👉 Diastolic BP decreases due to decreased peripheral resistance

                            

👄 Selective beta blockers (blocks only beta 1 receptor)

            

        ACUTE EFFECT

                    Beta 1 blockade: 

                            👉 Decreased heart rate and decreased cardiac contractility

                            👉 Decreased cardiac output

                            👉 Systolic BP tends to decrease

        

        PROLONGED USE EFFECT:

                            👉 Decreased cardiac output

                            👉 Adaptation of resistance vessels to persistently reduced cardiac output

                            👉 Decrease in peripheral resistance

                            👉 Systolic BP decreases due to decreased cardiac contractility

                            👉 Diastolic BP decreases due to decreased peripheral resistance

                            

👄 Beta blockers with additional alpha blocking property

 

    ACUTE EFFECT

                    Beta 1 blockade: 

                            👉 Decreased heart rate and decreased cardiac contractility

                            👉 Decreased cardiac output

                            👉 Systolic BP tends to decrease

                   Alpha blockade:

                             👉Decrease in total peripheral resistance

                             👉 Decrease in diastolic BP

                             👉 Compensatory increase in heart rate blockade by beta 1 receptor blockade

ORS tips for travel

 Practical off-label tip 😎

A one litre container may not be always handy.💭💭

Instead, a one litre bottle of packaged drinking water is easily available.💭💭💭

The ORS powder can be carefully emptied into the bottle of water.💭💭💭💭

The lid is capped and the bottle is shaken to dissolve the contents.💭💭💭💭💭

And the ORS is ready for consumption.💭💭💭💭💭

Two more important advice 

🎯 The prepared ORS should be used within 24 hours. If it remains after the period, it should be discarded and fresh ORS should be prepared.

🎯 The expiry date written on the sachet of the ORS powder should be checked before preparation. And not after consumption 😱😱

What's the "FUZZ" about drug promotional literature. Are FDCs of Iron with multivitamins rational???

💦Iron is given for iron deficiency anaemia. 

💦In this condition, there is no role of other vitamins unless and untill there is a concurrent deficiency of the other vitamins. 

💦Addition of other vitamins is generally harmless, but adds up significantly to the cost. 

💦This does not ascribe to the principles of rational pharmacotherapy which is so vital for the rational  practice of Medicine. 

💦That's why essential drug and rational prescribing is repeatedly stressed in your syllabus.

💧 Commercial organizations often promote their products out of context to earn revenue. 

💧 As practitioners of modern medicine, it is imperative on our part to exercise our knowledge and judgment in every prescription and not get carried by commercial promotions and incentives. 

💧 If you go through the NATIONAL LIST OF ESSENTIAL MEDICINE , you will not find such irrational Fixed Dose Combination in the list. 

💧 Prescription should be based in safety, efficacy, affordability and availability. 

💧 Talking in the same line, critical analysis of Drug Promotional Literature has been included in undergraduate syllabus so that Indian Medical Graduates can understand and "filter" the "Right" from the "Wrong" in Drug Promotional Literature provided by the commercial pharmaceutical companies. 

💧 And prescribe on the principles of "Essential Medicine" that is in the best interests of self and society.

The magic of furosemide

In acute pulmonary oedema, there is collection of fluid in alveoli.

The sequence of events is as follows.

👉Left ventricle is unable to pump adequate blood either due to systolic or diastolic failure.

👉Increased filling pressure in the left ventricle.

👉Transmission of increased filling pressure to left atrium, and then to pulmonary veins and then to pulmonary capillaries.

👉Increased pressure in the pulmonary capillaries causes oozing of fluid from pulmonary capillaries to alveolar lumen. This is pulmonary oedema.

Action of furosemide

👉Furosemide causes increase in systemic venous capacitance.

👉Fluid shifts from pulmonary circulation to systemic circulation.

👉Decrease in pulmonary hydrostatic pressure.

👉Back flow of fluid from alveoli to pulmonary capillaries.

👉Reversal of pulmonary edema.

👉The change in systemic hemodynamics occurs even before the diuretic action and therefore furosemide provides prompt relief in acute pulmonary oedema.