Targets have now been revised to 140/85 (max 150/90) and for diabetics 140/80 (max 140/90) .
A=Ace inhibitors eg Losarten 10-40mg , B=Betablockers like Atenolol 50-100mg , C=Calcium channel blocker like Amlodipine 5-10mg , D= Diuretics like bendrofluazide 2.5-5mg daily , E=Others like spirinolactone, alphablockers etc.
A -except black people and those over 55 when C or D would be more apporpriate to start with .
Step 2 A+D or C+D, combined A+d tablets are useful .
Step 3 - A+C+D
Step 4 add betablocker spirinolactone or alphablocker . Beta blockers like atenolol 25-100mg a day are indicated in those patients who have had a heart attack or suffer from angina but cannot be used if the patient is asthmatic , has chronic obstructive pulomonary disease or has heart block .
Calcium channel blockers are useful in the elederly and those with angina . However A cannot be used if the blood supply to the kidney is reduced as in renal artery stenosis so a creatinine level is advisable first and they cant be used in pregnancy . Cough is a troublesome side effect .
Next on the list are alpha blockers especially useful in patients with prostatic obstruction .
Usually treatment is initiated if the sustained systolic bp is 140-160 and the diastolic over 100 or those with 140-160 and diastolic 90-99 if there is evidence of target organ damage , chd risk factor over 15% or coronary heart disease. In diabetics if sustained is over 140 and over 90.
Blood pressure control helps prevent target organ damage and reduces heart deaths by 15% and strokes by about 25%.
The aim in all cases is to reduce the diastolic pressure to below 85 and the systolic if possibe below 145 . When the systolic is high before treatment say 200 and the diastolic low ie 85 or less .The heart has to pump the blood under some pressure for the blood to be able to get up to the brain when standing . If the pressure is too low eg after a heart attack the person will become clammy and then faint . If the blood pressure is too high then the arteries tend to become more rigid to accomodate this and eventually brittle and the ones in the brain may burst causing death of some brain cells ie a stroke , and some of the body part may be left paralyzed . The heart also may have to enlarge to deal with the high pressure and there is a higher incidence of heart faliure . Coronary heart disease becomes more common . That is why it is important to control blood pressure , the biggest single cause of premature deaths , which is too high and lower it to normal values.
A cuff is put around the arm , making sure the cuff is wide enough ie over 80% of the arm circumference and the air is let out slowly . The systolic pressure is estimated by lowering the pressure rapidly and checking for return of the pulse at the wrist . Then the cuff is inflated again and the pressure lowered gradually . The pressure with which the heart pumps out blood is called the systolic pressure and is the first sound heard . This value should ideally be lower than 160mm of mercury and higher than 100 . The big arteries eg aorta then have a passive recoil and keep the pressure high enough to get to the brain and this pressure is called the diastolic pressure and is recorded when the sounds become muffled and nearly silent .This pressure should be below 90 and above 60 . So ideal pressures are below 145/85 and 140/80 in diabetics and above 100/60 .
The blood pressure is taken after the patient has been sitting for five minutes and the cuff is at the level of the heart and the arm unsupported . Tight arm clothing should be loosened .Diabetics and elderly also have blood pressure checked when standing up .A difference of more than 20/10 between sitting and standing pressures is considered significant and could lead to dizziness on standing up .
Treatment is after a proper history taking , examination and investigations as detailed below . First non drug options over 3 -6 months - such as increased excercise eg walking fast for 20 mintues three times a week . weight loss so that the waist size gets less than chest size , reduction of salt or alcohol in diet if this is excessive , is done . The patient checked monthly for six months .
If the blood pressure is still high then a diuretic like bendrofluazide 2.5mg once in the morning is started for elderly over 65 . This drug is useful in the elderly and those with heart faliure but can cause gout and is not used in those with kidney faliure.
Isolated Systolic hypertension a risk factor for stroke then a drug like dihydropyridine can be tried .
Checks at the doctors
Of family history of hypertension , of alcohol intake -excessive amount can cause a rise in blood pressure -cut down to 21 units or less a week , of smoking . of excercise at least 20 in fast walking three times a week , past medical history , salt in diet , current meds
Examination - Ht , weight , abdo girth which ideally should be less than chest circumference . Look at the retina for signs of damage to the blood vessels . The heart for enlargement of the left ventricle , the abdomen for any masses .
Investigations - The urine is checked for protein , sugar and blood . Blood tests for urea , creatinine , uric acid and fasting sugar and thyroid function test . Liver function tests, lipids. FBC as anaemia can be a cause . A chest xray may be done as well as an ECG to detect heart strain due to the high blood pressure .
Some of the above may be done yearly .
Audits - Practices may check how many over a certain age group have had their blood pressure checked , how many of them have had investigations done and how these compare to national standards .How many are below the ideal level of 140/85 or close to it . If cardiovascular risk factors are recorded in the notes , what percentage have annual reviews at least All patients are checked every 5 years and those over 60 yearly till the age of 80.
Most cases of hypertension have no known cause and are called essential hypertension but rarely some other cause is found eg renal artery stenosis , low thyroid hormones , kidney tumors secreting nor adrenaline , ecess amounts of growth hormone etc.