Antenatal

Using Anatomy and Physiology explain the pupose of Venepunture and why this is relevant in screening

1.      Uterus /Abdominal examination 

•      Using anatomy and physiology explain how the uterus changes during pregnancy

The indications for abdominal examination in labour.

Midwife’s role in undertaking the examination?

Uterus

•        Under the influence of oestrogen the uterus grows

•        Hypertrophy - oestrogen causes the myometrial muscle to increase in size until 20 weeks gestation.

•        Hyperplasia - number of muscle cells also increases under the influence of oestrogen.

•        Progesterone also relaxes the smooth muscle of the uterus to allow it to stretch.

•        After 20 weeks the muscle tissue stretches to allow the fetus to grow.

•        By the 30th week the uterus is pear shaped again and is divided into the upper and lower segment.

•        By 36 weeks the fundus is level with the xiphi sternum. The pelvic floor muscles soften and the formation of the lower segment encourages the descent of the presenting part into the pelvis. (Engagement)

Myometrium

•        Layers of muscles become more defined

•        The inner circular layer at the cornua, cervix and lower segment develop to enable it to stretch the lower segment and cervix during labour.

•        Middle oblique layer develops to enable contractions to take place and to constrict after delivery.

•        Outer longitudinal layer develops to facilitate contraction and retraction

Cervix

•        Increase in width

•        Softening after the third month due to effects of increased oestrogen

•        Increased vascularity

•        Increased cervical mucosa

•        Increased glandular function

•        Thick plug of mucus forms = operculum

•        Last two weeks of pregnancy cervix is taken up into the lower segment =effaced.

Abdominal examination - An antenatal or intra-natal examination of the pregnant abdomen.

•        To assess fetal growth, size and well-being

•        To locate Fetal Position, Presentation, Lie, Attitude and Engagement

•        To detect deviations from normal

•        To auscultate the fetal heart

Lie -The relationship between the maternal spine and the fetal spine (longitudinal, transverse or oblique)

 

Attitude - The relationship between the fetal head and limbs to the fetal trunk (flexed, deflexed)

 

Presentation - The part of the fetus occupying the lower pole of the uterus (cephalic, breech)

 

Position - The relationship between the denominator on the presenting part and the maternal pelvis e.g ROA

 

Engagement - When the widest diameter of the presentation has passed through the pelvic brim

 

Descent - The amount of fetal head palpable abdominally in relationship to the amount of descent determined by vaginal examination

 

Indications

•        At each antenatal assessment (N.I.C.E 2008)

•        Prior to vaginal assessment

•        Prior to auscultation of the fetal heart, or commencement of C.T.G

•        Admission to hospital

•        Possibly daily, while in hospital

•        Prior to invasive screening e.g. amniocentesis / ECV

 

Technique

•        Inspection – size, shape, fetal movements, skin changes

•        Palpation – fundal measurement, fundal palpation, lateral palpation, pelvic palpation

•        Auscultation – pinnards one full minute, maternal pulse

•        Communication

•        Documentation

•        REFER if nesc

Midwife’s role

•        Obtain consent

•        Ensure privacy

•        Ensure bladder is empty

•        Position – semi-recumbent, with one pillow

•        Bend legs slightly if abdominal muscles are firm

•        Minimise supine-hypotension with a wedge,

•        Wash and warm hands

Using anatomy and physiology explain the extra nutrients are required during pregnancy, ie 200 kcals, 6g more protein. Also what each nutrient is for, such as bone development with calcium.

What supplements and why we would recommend them for which groups of women.

Advise at first contact of Folic acid supplementation of 400 mcgs per day in addition to the 200 mcgs per day received from normal diet. This is needed for nerve development and to prevent neural tube defects.

To maintain a healthy balanced diet and that there is no need for additional calories initially. Advise on food hygiene; meat well cooked salad and vegetables washed, as soil and cat faeces contains a parasite which can cause toxoplasmosis. This can cause miscarriage and stillbirth.

Carbohydrates for energy extra 200kcals per day required but 3^rd trimester only

Protein for growth of foetus, placenta and uterus an extra 6 grams per day is needed.

Fat is needed for energy and the cholesterol is used by the foetus to make bile salts, steroid hormones and cell membranes.

Keep well hydrated and an increase in fibre may be needed due to a natural decrease in peristalsis from the raised progesterone levels, increasing the likelihood of constipation.

NICE 2007 CG 62 -Vitamin D 10 micrograms a day advised as a supplement, difficult to get from diet alone but especially to women who are: South East Asian, African, Caribbean or Middle Eastern family origin.

Women who have limited exposure to sunlight, housebound women or covered when outdoors.

Women who have a diet low in oily fish, eggs, meat fortified margarine or breakfast cereals.

Women with a pre-pregnancy BMI of 30kg/m²

It is required for bone growth and repair, it is synthesized in the skin and aids absorption of calcium.

Vitamin A is required for growth, development and differentiation of tissues. Found in orange, yellow and green fruit and vegetables, beta-carotene. Retinol, which is found in liver is not recommended as can cause nerve defects and abnormalities in the CNS.

Vitamin C is needed to increase the use and absorption of iron in the body. Found in kiwi fruit, oranges and broccoli.

Vitamin E is required for tissue growth. Found in tomatoes spinach and fortified margarines.

Vitamin D is to increase the use and absorption of calcium in the body. Found in oily fish and dairy products.

 

Thiamin B1 and Riboflavin B2 are needed for carbohydrate metabolism and cell respiration . Found in pork and yeast products

Calcium needed for bone and muscle development in the foetus and to prevent maternal muscle cramps and nerve pain. Bone and teeth structure essential for blood clotting and muscle contraction. Found in dairy

Iron is needed to produce haemobglobin which is the O₂ carrying molecule in the blood, naturally less due to physiological haemodilution. Found in red meat and green leafy vege’s.

Folic Acid needed for DNA production, cell division and maturation of red blood cells, also to prevent NTD’s such as anencephaly and spina bifida. A higher dose is need, 5mgs per day, in women with coeliac disease, previous NTD’s,; sickle cell, diabetes and epilepsy sufferers. Found in green leafy vege’s, bread and fortified breakfast cereals.

Vitamin D is to increase the use and absorption of calcium in the body. Found in oily fish and dairy products.

 

Thiamin B1 and Riboflavin B2 are needed for carbohydrate metabolism and cell respiration . Found in pork and yeast products

Calcium needed for bone and muscle development in the foetus and to prevent maternal muscle cramps and nerve pain. Bone and teeth structure essential for blood clotting and muscle contraction. Found in dairy 700mg per day in a/n and 1200mg p/n for breastfeeding mothers

Iron is needed to produce haemobglobin which is the O₂ carrying molecule in the blood, naturally less due to physiological haemodilution. Found in red meat and green leafy vege’s.

Folic Acid needed for DNA production, cell division and maturation of red blood cells, also to prevent NTD’s such as anencephaly and spina bifida. A higher dose is need, 5mgs per day, in women with coeliac disease, previous NTD’s,; sickle cell, diabetes and epilepsy sufferers. Found in green leafy vege’s, bread and fortified breakfast cereals.

Alcohol – Avoid for preconception to three months = increased risk of miscarriage. Advice to drink no more than 1-2 units, once-twice a week. Binge drinking harmful to baby.

Venepuncture - technique in which a vein is punctured transcutaneously by a needle for the purpose of withdrawing a specimen of blood

How to ensure the physical & psychological comfort of the client.

• Explanations of how the procedure is performed & the reasons for the procedure, needs to be provided.
• Consent must be obtained.
• Position of client, lying or sitting.
• Privacy.
• Use of pillows etc.
• A good light source.

 

Anatomy and Physiology.

·       N.B. Blood must only be taken from a vein. Arterial samples would be taken by medical staff only.

• Veins of choice = basilic, cephalic, and the median cubital vein.
• Additional blood volume (angiogenesis, vasodilation) and the rise in body temperature (large mass to volume), usually makes venepuncture from pregnant women easier.
• Most venepuncture is carried out in the region of the cubital fossa and care must be taken to avoid the arteries and nerves, which generally are deeper and lie between the veins.
• If the artery or nerve is hit then severe pain can occur, in the case of an artery the pain is accompanied with prolonged bleeding. The procedure MUST be stopped.

Choosing a site.

• The area must be free from inflammation, bruising or infection. Avoid reusing a site.
• The vessel must be easily palpated and / or visible.
• If an intravenous infusion is in situ then the other limb should be utilised to avoid dilution of the sample.
• Mothers often know which is the most successful site from previous blood tests.
• Occasionally it becomes necessary to take blood from elsewhere, for example the back of the hand but this must be performed by somebody with adequate experience, as it is more difficult and more painful

Principles of Aseptic (clean) technique.

• Hands should be washed thoroughly.
• Gloves are recommended as they provide protection but are unlikely to be sterile.
• Debates surround the use of alcohol swabs. If swabs are used however, the skin should be rubbed firmly using the swab and then left to dry completely before venepuncture is commenced.
• The vein should not be repalpated, as this will contaminate the area.
• Needles and blood taking equipment should be completely disposable and needles should be sterile
• Blood spillages must be cleaned up immediately.

Equipment.

Receiver

Tourniquet

Blood bottles.

21G (green) needle & appropriate sized syringe.

OR a green vacutainer needle and plastic connector.

Alcohol swab.

Gloves.

Gauze or cotton wool and tape.

Plaster (note any allergies).

Specimen request forms.

Sharps box.

 

Potential problems that may arise.

Client feels faint or actually faints.

Needle phobias or low pain tolerance – use anaesthetic creams & plenty of reassurance.

Needle stick injuries - must be reported & dealt with immediately.

Failure to obtain blood – Do not keep trying but get somebody with more experience. Try warming or gently rubbing the site prior to attempt if veins are not very dilated and avoid advancing the needle too far and going through the vein.

Bruising – remove tourniquet before removing the needle & ensure adequate pressure is applied to site afterwards. Avoid bending the arm afterwards until bleeding stopped.

Arterial puncture – blood is bright red and easily aspirated. Damage is unlikely but firm pressure must be applied for at least 5 mins.

 Nerve damage – extremely rare, the client may complain of pain or tingling. STOP procedure.

Health & Safety.

• Clean / aseptic technique should be used at all times to minimise the risk of contamination and localised infection.
• All used equipment needles etc must be disposed of immediately in the nearest sharps box.
• Sharps boxes should not be overfilled - to avoid sharps injuries.
• NEVER re -sheath any needles.
• Treat all blood as if it infectious.
• Report any injuries and deal with them appropriately.

 

Taking Blood

·       Decide on the blood tests to be performed.

• Inform the client and obtain their consent
• Collect & assemble the equipment required.
• Position the client comfortably and support the limb.
• Wash hands and put on gloves.
• Apply the tourniquet carefully to avoid pinching the skin.
• Select a vein by observation and palpation.
• Cleanse the skin with an alcohol swab & allow to dry for 30 seconds.
• Anchor the vein with the thumb of non-dominant hand.
• Insert needle into vein, lumen uppermost, at a 30-degree angle until the lumen is no longer visible. Observe for a flashback if using a syringe.
• Support needle with non-dominant hand to avoid it moving.
• Using your dominant hand draw back on syringe plunger or insert and swap vacutainer bottles when filled. Gently agitate filled bottles to mix in any additives.
• Release the tourniquet.
• Place cottonwool ball over puncture site and withdraw needle, applying immediate pressure for atleast 1 minute.
• Dispose of any waste, equipment & sharps in the correct containers.
• Inspect puncture site and apply a plaster or tape over cottonwool
• Remove gloves and wash hands.
• Label bottles, complete appropriate forms and send to the lab.
• Document which blood tests have been performed in the client’s records.
• Inform the client about how she will be notified of any results.

Ensuring the physical & psychological comfort of the client:-

• Explain procedure and obtain consent.
• Use of anaesthetising creams if appropriate.
• Positioning of client.
• Privacy.
• Support limb.
• Good light source.

Potential Problems: -

• Client may feel faint or actually faints.
• Needle phobias.
• Needlestick injuries.
• Failure to obtain blood.
• Bruising.
• Arterial puncture.
• Nerve damage.vENEPUNTURE

Changes in pregnancy

 

Renal ureters

·        Influenced by progesterone in 1^st trimester

·        Dilate, elongate

·        Displaced laterally

·        Hold 25 times more urine (stasis of urinary flow)

 

Bladder

·          Capacity doubles by term

·          Under the influence of oestrogen

·          Bladder muscle hypertrophies

·          Increase in size and blood vessels

Urethra

·          Short in females

·          Close to rectum and vagina

·          Risk of ascending infection

·          Pelvic floor muscles relax due to progesterone

Protection

·          Micro-organisms are washed towards urethra

·          One-way valve at junction of ureters and bladder may prevent reflux of urine

·          Bactericidal effect - low urinary pH, Urea in urine

Screening

·        Screening pregnant women for asymptomatic bacteruria with urine culture significantly reduces asymptomatic urinary tract infections, low birth weight, and preterm delivery (N.I.C.E. 2008)

·        A specimen obtained at 12 to 16 weeks’ gestation will detect approximately 80 % with asymptomatic bacteraemia.

Urine

·        Glycosuria – more common in pregnancy

·        Proteinuria  – in labour due to rupture of membranes, increased vaginal discharge, blood stained mucous ‘show’

·        Ketones – if mild is insignificant

Indications

·        Part of antenatal examination   (NICE 2008)

·        Screening for asymptomatic bacteriuria

·        During labour

·        On admission to hospital  - baseline

·        Maternal disorders e.g. raised BP diabetes

·        Signs of urinary tract infection

Midwifes role

·        Holistic assessment of woman

·        Gain consent, communicate procedure to woman

·        Undertake procedure correctly

·        Recognise deviations for normal

·        Refer to other professionals, if needed

·        Effective explanation and education of woman

·        Correct documentation    (NMC 2008)