Obstetrics Flashcards
Describe the airway changes in pregnancy (3)
- Engorgement and friability of the respiratory tract + mucosal oedema and capillary engorgement of nasal/OP/laryngeal - leads to increased iatrogenic trauma due I+V
- Increased weight and breast size makes laryngoscopy more difficult
- Delayed gastric emptying, increased gastric pressure + gastro-oesophageal incompetence increased risk of aspiration
1 in 250 failed airways
Describe the respiratory changes in pregnancy (4)
- Increased TV and RR secondary to increased oxygen demand
- TV increases at expense of ins. and exp. reserve volume which decrease function residual capacity
- Gravid uterus decreases use of IC muscles
- Diaphragm rises late in pregnancy (thoracostomies should be higher)
Describe circulatory changes in pregnancy (8)
- Steady decrease BP in 1st trimester caused by progesterone which is profoundly vasodilatory. Normal by 3rd following activation of renin-angiotensin syndrome (increases retention of water and Na+)
- Gradual increase in SV by increase in ventricular wall muscle mass and end-diastolic volume (from increase in blood volume)
- HR increase 10-20bpm
- By second trimester CO increased by 40%
- Increased plasma volume leads to dilutional aneamia
- SVR decreases by 30% = postural hypotension
- Aortovacal compression by late second trimester
- Blood diverted away from uterus during haemorrhage which means up to 35% circulating volume can be lost without tachycardia
Where should IOs be sited in pregnancy?
Humeral
Which antibiotics are c/i in pregnancy?
Trimethoprim and tetracyclines (doxy)
When should NSAIDs be avoided in pregnancy?
3rd trimester
Which opiate is preferred in pregnancy?
DH118
What anti-hypertensives should be avoided in pregnancy?
Ace inhib/ ARBS
Which anti-epileptics should be avoided in pregnancy?
Sodium valporate
When are pregnant women at increased risk of aortic dissection?
3rd trimester
What is the increased risk of ACS in pregnancy?
3-4 x
What is posterior reversible encephalopathy syndrome (PRES)?
- 3rd trimester headache, with pre-eclampsia
- headaches/seizures/corticul blindness
- vasogenic brain oedema
How do you treat Posterior Reversible Encephalopathy Syndrome (PRES)? (2)
- Anti-hypertensives
- Magnesium
What is Reversible Cerebral Vasoconstriction Syndrome (RCVS)?
Post partum headache
Severe HTN and thunderclap headache
Multifocal segmental cerebral artery vasoconstriction
How do you treat Reversible Cerebral Vasoconstriction Syndrome (RCVS) ?
Nimodopine
What is HELLP syndome?
Haemolysis
Elevated Liver enzyems
Low Platelets
Which women with bleeding in pregancy should get anti-resus D and at what dose?
- All
- 250 IU if < 20 weeks
- 500 IU if > 20 weeks
What is the Kleihauer test?
Gives indication of feto-maternal haemmorhage
:In gestational HTN under what value should we aim for and what value should we admit for?
- Less than 135/85
- Over 160/110
What is 1st, 2nd and 3rd line for gestational HTN?
- Labetalol PO 1st
- Nifedipine PO 2nd line
- Methyldopa PO 3rd line
What are the diagnostic criteria for pre-eclampsia?
2 of the following:
1. BP >140/90
2. Proteinurea (++ protein)
3. Oedema
What are the symptoms of pre-eclampsia? (5)
- Frontal headache
- RUQ pain
- Visual symptoms
- Oedema
- N/v
What are the signs/symptoms of severe pre-eclampsia? (6)
- Ongoing headache
- Visual schotomata
- Epigastric pain
- Oliguria
- Progressive worsening biochem
- BP >160/110
What signs suggest pre-eclamptic patients are moving towards eclampsia? (3)
- Confusion
- Tremor/twitching
- Hyper-reflexia