Week 3 part 1 Flashcards
What insicion is used for lower segment caesarean section, laparotomy, abdo and vaginal hysterectomy and laparoscopy?
Common Surgical Incision (O&G)
Muscle layers of abdomen from outer to inner?
External oblique
Internal oblique
Transversus abdominus
What muscles attach between lower ribs and iliac crest, pubvic tubercle and linea alba?
External obliques
What is linea alba?
Midline blending of aponeuroses
What do fibres of external intercostals run in same direction as?
External obliques (
What do internal obliques attach between?
LOwer ribs, thoracolumbar fascia, iliac crest and linea alba
What is made up of the combined aponeuroses of anterolateral abdominal wall musclers and lies immediately deep to superficial fascia?
Rectus sheath
Nerve between transversus abdominus and internal oblique?
Ilioinguinal nerve
What do 7th to 11th intercostal nerves become?
Thoracoabdominal nerves
T12 nerve>?
Subcostal
L1 nerves?
Iliohypogastric and ilioinguinal
What arteries supply anterior abdominal wall?
Superior and ingerior epigastric arteries
continuation of internal thoracic
emerges at superior aspect of abdominal wall
lies posterior to rectus abdominis
Superior epigastric arteries
branch of the external iliac artery
emerges at inferior aspect of abdominal wall
lies posterior to rectus abdominis
Inferior epigastric arteries
What supplies lateral abdominal wall muscles?
Intercostal and subcostal arteries
Continuations of posterior intercostal arteries
Emerge at lateral aspect
In a lower section caesarian section what way are rectus muscles moved apart? They are not cut.
Lateral direction toward nerve supply
What layers are seen when opening laparotomy?
Skin and fascia
Linea alba
Peritoneum
In a laparoscopy - if a lateral port is required care must be taken to avoid what artery?
Inferior epigastric artery
What artery emerges just medial to deep inguinal ring (located halfway between ASIS and pubic tubercle)?
Inferior epigastric artery - branch of external iliac artery
From 20 weeks how often will pregnant women be seen/
At 4 week intervals
From 30 weeks how often will pregnant women be seen?
At 2 week intervals
At 28 weeks if rhesus negative what will be offered?
Anti D
In pregnancy: at 12 weeks what is offered?
FBC, antibodies, glucose, syphilis, rubella
In pregnancy: at 16 weeks what is done?
Triple test or alpha feto protein
When is first ultrasound down in pregnancy?
At 18 weeks
At 12 weeks gestation what will the uterus be at the level of?
Pubic symphisis
At 20 weeks gestation where will the uterus almost reach?
The umbilicus
At 28 weeks where will the uterus almost have reached?
Xiphisternum
In pregnancy when is booking scan performed?
Around 6 to 7 weeks
In embyonoc period how does the embryo receive nutrition?
From yolk sac via vitelline duct
Learning disabilities Palmar creasing Short stature Wide-brim nose Reeding hair line Small chin Short digits
Downs syndrome
In first trimester - how is downs syndrome assessed risk?
Measure skin thickness behind fetal neck using utrasound = nuchal thickness
Combined with HCG and PAPP-A
When is down syndrome nuchal thickenss tested?
At 11 - 13 +6 weeks
In the second trimester how is downs risk assessd?
- Blood sample at 15-20 weeks
2. Assay of HCG and AFP
If the personal risk for downs syndrome baby is greater than 1:250 then it is high risk - what is then required?
Further investigation - amniocentesis
In downs syndrome risk assessment if AFP and HCG are normal what does risk depend on?
Maternal age
In downs syndrome risk assessment if afp IS HIGH and HCG low then what is risk ?
Low - but high spina bifida risk
In downs syndrome risk assessment if high HCG and lower AFP what is risk?
Hihg - irresepctive of maternal age
When is amniocentesis usually performed and what is the risk?
After 15 weeks
Risk of miscarriage 1%
Chorionic villus sampling is used for downs syndrome testing - what is risk and when is it performed?
12 weeks
Carries miscarriage rate of 2%
In days 5 - 7 what happens to blastocyst?
Implants
In the blastocyst what do inner cells develop into?
Embryo
In the blastocyst what do outer cells develop into?
Burrow into uterine wall and become placenta
Is the trophoblast layer of blastocyst on surface of cell?
Yes
At what day does blastocyst become buried in uterine lining?
By day 12
What two tissue types make up the placenta?
Trophoblast (chorion)
Decidual
In placental development what do trophoblast cells (chorion) differentiate into>
Syncytiotrophoblasts - these invade decidua and break down capillaries to form cavities filled with maternal blood
What does each placental villi cpntain?
foetal capillaries separated from maternal blood by thin layer of tissue
When do the placenta and foetal heart begin to function?
By 5th week of pregnancy
In placental development Human Chorionic Gonadotropin HCG signals the corpus luteum to secrete progesterone - what does this stimulate?
Decidual cells to concentrate glycogen, proteins and lipids
What structure works as a physiokogical arteriovenous hunt?
Placenta
As placenta develops where does it extend hair like projections to?
Into uterine wall
What is present in teh intervillous space?
Maternal blood
What does circulation within the intervillous space act partyl as?
Arteriovenous shunt
What is in umbilical blood?
Mixing of arterial and venous blood - oxygen poor
How does fetal, oxygen saturated blood return to fetus?
Through umbilical vein.
How does maternal oxygen poor blood flow back?
Through uterine veins
What three factors allow sufficient supply of oxygen to fetus?
- Fetal Hb (increase ability to carry O2)
- Higher Hb (concentration in fetal blood)
- Bohr effect (fetal Hb can carry more O2 in low carbon dioxide than in high CO2 partial pressure)
Water diffusion in placenta increases during pregnancy up to what week?
35th weeks
In what direction of flow to iron and calcium only go?
From mother to child!
What method of transport does glucose use to pass the placenta?
Siplified transport
Name 4 teratogenic drugs?
- Thalidomide
- Carbamazepine
- Coumarins
- Tetracycline
At what weeks gestation does HCG spike?
10 weeks
What does HCG prvent in pregnancy?
Involution of corpus luteum
At what week is human chorionic somatomammotropin produced?
Week 5
Give three functions of HCS
- Growth hormone like - effects protein and tissue formation
- Decreaes insulin sensitivity in mother: more glucose for fetus
- Involved in breast development
In pregnancy what hormone develops decidual cells, decreases uterus contractility, and prepares for lactation?
Progesterone
In pregnancy what hormones are involved in breast development and relaxation of ligaments ?
Estrogens
In pregnancy what is role of estradiol?
Enlargement of uterus
In pregnancyt what is role of estriol?
Estriol level - indicator of vitality of fetus
CRH produced by placenta can cause what adverse effect on mother?
ACTH - aldosterone (hypertension)
cortisol (oedema, insulin resistance leading to gestational diabetes)
HCG and HC thyrotropin produced by placenta cause what adverse effects in motjers?
Hyperthyroidism
Increase calcium demands by placenta cause what adverse effect in mothers?
Hyperparathyroidism
What is increase in cardiac output during pregnancy due to?
Demands of uteroplacental circulation
what percentage above normal is cardiac output in pregnancy?
30-50% (beginning week 6 and peaking 24)
When does CO decrease in pregnancy?
In last 8 weeks (becomes sensitive to body position - uterus compresses VC)
Increases 30% more in labour
In second trimester what happens to blood pressure?
It drops (uteroplacental circulation explans and peripheral resistance decreases)
In pregnancy what does plasma volume increase proportionally with>
cARdiac output
What happens to RBC in pregancy?
They increase - erythropoesis (thus Hb is decreased by dilution)
In pr4egnancy; progesterone signals to brain to lower CO2 levels what then happens?
- RR increaes
- tidal volume increases
- pCO2 decreases
In pregnancy what happens to GFR and Renal plasam flow?
Increases. Also increase in urine formation
In opregnancy - ppstural changes in baby afffect renal functions. What happens if upright psoition?
Decrease renal function
What is pre-eclampsia?
Pregnancy induced hypertension and proteinuria
In pre eclampsia what happens to BP, kidney function and RBF and GFR?
BP increases since 20th week
Salt and water retention oedema
RBF and GFR decrease
In pregnancy: vascular spasms, extreme hypertension, chronic seizures & coma
Eclampsia treat with vasodilators and cesarean section
How many more calories a day should be ingessted by mother?
250 to 300 extra (85% fetal metabolism, 15% stored as maternal fat)
When is mothers anabolic phase?
1 - 20th week
When is mothers accelerated starvation phase
21-40 week (esp last trimester) - high metabolic demands of fetus
In anabolic mother phase what happens to sensitiity of insulin?>
Increased
In catabolic mother phase what happens to senstiivity of insulin?
Resistance
Before parturition what is given to prevent intracranial bleeding during labour
Vitamin K
What hormone increases contractions and excitability of uterine tissue?
Oxytocin
Braxton hicks contractions - do they increase or decrease towards end of pregnancy?
Increase
What does strethc of cervix by fetal head do to contractility?
INcreases - cervical strethcing also causes further oxytocin release
As well as oxytocin stimulating uterus contractions what does it also stimulate?
Placenta to make prostaglandins - stimulate more contractions
What are the 3 stages of labour?
- Cervical dilation 8-24 hours
- Passage through birth canal (few mins to 30)
- Expulsion of placenta
Lactation: what hormone causes growth of ductile system?
Estrogen
Lactation: what hormone develops lobule-alveolar system?
Progesterone
Lactation: what do E and P do to milk production?
Inhibit it = at birht sudden drop in these hormones
Lactation: what hormone stimulates milk production?
Prolactin (1-7 days after birth prolactin induces high milk production)