Chronic Hypertension Flashcards
1
Q
What is blood pressure?
A
- it is the pressure exerted by blood volume on the blood vessel walls
- as the heart pumps blood, it causes a change in its speed of flow and this blood exerts a pushing force when it encounters blood vessel walls, creating a pressure
- blood pressure generally refers to arterial pressure, its value varies throughout each contraction - relaxation cycle
—> during systole (contraction) more blood enters the arteries from the ventricle than leaves them through the arterioles (highest pressure)
—> during diastole (relaxation) no new blood enters the arteries from the ventricle but blood leaves under pressure from elastic force in the wall of the arteries (lowest pressure)
2
Q
What variable factors can affect blood pressure?
A
- the volume of blood in the vessel, which is influenced by the body’s total blood volume and the volume pumped by the heart (cardiac output)
- the strength of heart contractions and how often the heart beats, which influence cardiac output
- the degree of stretch of the vessel wall
- the resistance to blood flow downstream from the vessel in question
3
Q
What is chronic hypertension?
A
- hypertension in pregnancy is defined as a systolic blood pressure of over or equal to 140 mmHg or a diastolic blood pressure of over or equal to 90 mmHg
- chronic hypertension describes all hypertension that exists before pregnancy
—> most women in this group have essential hypertension and have no apparent underlying cause - occurs in 2% of pregnancies
4
Q
What is the difference between chronic and pregnancy induced hypertension?
A
- in the 1st trimester of pregnancy marked vasodilation causes a drop in systemic vascular resistance which sees a fall in BP in both normotensive and hypertensive women
- therefore a woman with CHT may not actually be hypertensive until late in the 2nd trimester
—> so CHT cannot be diagnosed unless non-pregnant BP readings are available - CHT and PIH are therefore difficult to differentiate and postnatal follow-up should involve medical review of BP at 6 weeks to determine this
5
Q
What are the complications of chronic hypertension?
A
- IUGR
- placental abruption
- severe hypertension (>160/110)
- superimposed pre-eclampsia
6
Q
What are the issues with chronic hypertension in pregnancy?
A
- risk assessment for pre-eclampsia
- reducing the risk of pre-eclampsia
- treatment of hypertension
- screening for pre-eclampsia
7
Q
What is the medical management and care for hypertension?
A
- all women with CHT should be referred for specialist input in the 1st trimester, this will include risk assessment and treatment review
- BP medication is commonly reduced or stopped in the first 20 ekes of pregnancy and may then be required often in increasing doses towards term
—> labetalol - usually first choice medication in pregnancy, should be avoided in asthmatics
—> nifedipine
—> methyldopa
—> diuretics
8
Q
What is the midwives role in caring for a woman with hypertension in pregnancy?
A
- regular antenatal appts
- SFH measurement
- BP
- urinalysis
- ask about symptoms of pre-eclampsia
9
Q
What are the issues in labour?
A
- IOL from 37 wks
- earlier delivery in event of severe uncontrolled BP or other significant antenatal complications
- usual antihypertensive medications during labour
- avoidance of syntometrine or ergometrine
- CTG
10
Q
What is the midwives role in caring for the woman with hypertension?
A
- hourly BP in labour
- oxytocin for 3rd stage
- normal midwifery care
11
Q
What are some of the postpartum issues?
A
- continue antenatal hypertensives
- stop methyldopa if used
- ensure appropriate follow-up
12
Q
What is the midwives role postnatally?
A
- GP review at 2 wks
- daily bp check days 1 and 2
- bp check once days 3-5 or more often if indicated/requested
- encourage compliance with antihypertensive medication
- advise on lifestyle factors
