Friday, October 15, 2021

The drug that saved lives in COVID 19

 The debate of using steroids in ARDS secondary to infective etiology has been raging since the inception of the concept, when at the fag end of 2019, a virus, SARS COV2, emerged as the one of the deadliest ever in the history of human civilisation. Desperate situations need desperate measures. And once again, in the desperate bid to save lives, mankind turned to steroids in the hour of crisis. The results were not miraculous but optimistic. Patients who were critically ill requiring oxygen or mechanical ventilation seemed to benefit from the new weapon in the armamentarium. This occurred at a stage when the performance of the ‘big warriors’ viz. the antivirals remained below expectation. The ‘hope’ in the hour of darkness resulted in the worldwide use of steroids on a massive scale, sometimes even, over enthusiastic and premature. Reports of secondary infections attributed to steroid induced immunosuppressive started emerging, but the exact cause of the phenomenon remained an enigma. Over time, the use of steroids in COVID with pulmonary devitalisation has become a global consensus. Considered to be the ‘game changer’ in the management of seriously ill COVID-19 with lung injury, the surfacing results of the ongoing and completed studies have already proved its usefulness in the fight against the worst pandemic in history. With time, the virus is expected to weaken and human zeal to live and love will sweep the  tragedies into oblivion. However, science and society will for ever preserve the ‘treasure’ of the powerful medicine that is a ‘two edged sword’, but when used judiciously to ‘strike the iron when it is hot’ can save lives and ‘do no harm’.

Tuesday, October 5, 2021

The buried mystery of oestrogen effects in post menopausal women

 The cardiovascular protective effect of estrogen in premenopausal women is assumed to be due to improvement in HDL:LDL ratio, diminished atherogenesis and improved vascular health attributed to NO and PgI. These factors formed the basis of their use in postmenopausal women for better cardiovascular outcomes. Indeed, estrogens provide cardiovascular protection in early post menopause but with advancement of age, the protective effects wane. In the year 2002, the findings of the landmark trial, Women's Health Initiative, showed for the first time that the risks associated with HRT outweigh the benefits and henceforth, the popularity of HRT declined rapidly. The real world evidence generated from the trial was enough to overwhelm the popular pharmacological concepts of estrogenic  cardiovascular benefits and ever since the mechanism of estrogenic effect in postmenopausal women has remained a mystery. Perhaps, it will be never be possible to know, because estrogens are no longer given to postmenopausal womem for long years. The use has become restricted for vasomotor symptoms and atrophic vaginitis. They are given for the shortest possible time in the smallest possible dose. At present, we can only speculate the possible reasons for adverse cardiovascular effect of estrogen in post menopausal women. One reason may be that estrogen increase the synthesis of clotting factors in the liver and that may be responsible for increased incidents of deep vein thrombosis, acute myocardial infarction etc. But then, why they don't increase the cardiovascular risk in premenopausal women, no body knows. There are many mysteries of nature which are yet not known to mankind.

Friday, October 1, 2021

The history of use of hormone replacement therapy in post menopausal women

 Estrogens are cardio protective. The cardiovascular health of women is seen to be better than their male counterparts till the date when menopause sets in and the level of the sex hormones declines in women. The development of pharmaceutical expertise to separate and purify the female sex hormones in the early part of the twentieth century opened vistas for their use in post-menopausal women. Very soon, hormone replacement therapy become widely popular for improving the physical, psychological and cardiovascular health of post-menopausal women. It was known long before that unimpeded estrogenic action results in endometrial proliferation and increases the risk of endometrial carcinoma. Therefore, from the very beginning, hormone replacement therapy involves the use of progesterone in a cycle manner along with oestrogen. Numerous observational studies showed the benefits of HRT on the cardiovascular health of women.The use of hormone replacement therapy for presumed cardiovascular benefit continued for many years. For the first time, a study sponsored by the National Institute of Health, the Women’s Health Initiative showed that Hormone replacement therapy is associated with increased cardiovascular morbidity. The landmark study resulted in the drastic decline of hormone replacement therapy in post-menopausal women. The present recommendation of HRT in post-menopausal women is restricted to control of vasomotor symptoms and atrophic vaginitis in early menopause and should be withdrawn as early as possible. HRT has also been found to increase breast cancer, gallstones and migraine.




 

To continue...


Tuesday, September 14, 2021

Mechanism of anti-hypertensive action of beta blockers

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

πŸ‘„ Non-selective beta blockers (blocks both beta 1 and beta 2 receptors): 

            ACUTE EFFECT

                    Beta 1 blockade: 
                            πŸ‘‰ Decreased heart rate and decreased cardiac contractility
                            πŸ‘‰ Decreased cardiac output
                            πŸ‘‰ Systolic BP tends to decrease

                    Beta 2 blockade:
                            πŸ‘‰ Increased peripheral vascular resistance
                            πŸ‘‰ Diastolic BP tends to increase

               NET ACUTE EFFECT: No change in BP
                
               PROLONGED USE EFFECT:
                            πŸ‘‰ Decreased cardiac output
                            πŸ‘‰ Adaptation of resistance vessels to persistently reduced cardiac output
                            πŸ‘‰ Decrease in peripheral resistance
                            πŸ‘‰ Systolic BP decreases due to decreased cardiac contractility
                            πŸ‘‰ Diastolic BP decreases due to decreased peripheral resistance
                            

πŸ‘„ Selective beta blockers (blocks only beta 1 receptor)
            
        ACUTE EFFECT

                    Beta 1 blockade: 
                            πŸ‘‰ Decreased heart rate and decreased cardiac contractility
                            πŸ‘‰ Decreased cardiac output
                            πŸ‘‰ Systolic BP tends to decrease
        
        PROLONGED USE EFFECT:

                            πŸ‘‰ Decreased cardiac output
                            πŸ‘‰ Adaptation of resistance vessels to persistently reduced cardiac output
                            πŸ‘‰ Decrease in peripheral resistance
                            πŸ‘‰ Systolic BP decreases due to decreased cardiac contractility
                            πŸ‘‰ Diastolic BP decreases due to decreased peripheral resistance
                            

πŸ‘„ Beta blockers with additional alpha blocking property
 
    ACUTE EFFECT

                    Beta 1 blockade: 
                            πŸ‘‰ Decreased heart rate and decreased cardiac contractility
                            πŸ‘‰ Decreased cardiac output
                            πŸ‘‰ Systolic BP tends to decrease
                   Alpha blockade:
                             πŸ‘‰Decrease in total peripheral resistance
                             πŸ‘‰ Decrease in diastolic BP
                             πŸ‘‰ Compensatory increase in heart rate blockade by beta 1 receptor blockade

Sunday, September 12, 2021

ORS tips for travel

 Practical off-label tip 😎

A one litre container may not be always handy.πŸ’­πŸ’­

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

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

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

And the ORS is ready for consumption.πŸ’­πŸ’­πŸ’­πŸ’­πŸ’­


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???

πŸ’¦Iron is given for iron deficiency anaemia. 

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

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

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

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


πŸ’§ Commercial organizations often promote their products out of context to earn revenue. 

πŸ’§ 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. 

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

πŸ’§ Prescription should be based in safety, efficacy, affordability and availability. 

πŸ’§ 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. 

πŸ’§ 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.


πŸ‘‰Left ventricle is unable to pump adequate blood either due to systolic or diastolic failure.

πŸ‘‰Increased filling pressure in the left ventricle.

πŸ‘‰Transmission of increased filling pressure to left atrium, and then to pulmonary veins and then to pulmonary capillaries.

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

Action of furosemide


πŸ‘‰Furosemide causes increase in systemic venous capacitance.

πŸ‘‰Fluid shifts from pulmonary circulation to systemic circulation.

πŸ‘‰Decrease in pulmonary hydrostatic pressure.

πŸ‘‰Back flow of fluid from alveoli to pulmonary capillaries.

πŸ‘‰Reversal of pulmonary edema.

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

Lidocaine and phenytoin- both are sodium channel blockers. Lidocaine is a local anaesthetic and an anti-arrhythmic. Phenytoin is an anticonvulsant. What explains their differential action? Is it because of their difference in pharmacokinetics.

 Drugs, more than often, have multiple actions. The ability of drugs to interact with different targets and sometimes same target in differe...