Obstetrics emergencies Flashcards
Why is there a risk of hypoxia during pregnancy?
Tidal volume increases by up to 50%
Residual capacity is reduced by 25%
Oxygen demand is increased by 20%
There is a reduced ability and reserve to compensate for illness or injury.
What causes breathlessness in pregnancy?
The rib cage undergoes a transformation, upward displacement, widening at its base to accommodate the presence of a pregnant uterus.
Classically women notice when resting / speaking. May get better or worse with exercise.
What are the red flags of breathlessness in pregnancy?
Sudden-onset breathlessness
Orthopnoea
Breathlessness with chest pain or syncope
Respiratory rate >20 breaths per minute
Oxygen saturation <94% or falls to <94% on exertion
Breathlessness with associated tachycardia
What are the cardiovascular changes during pregnancy?
Cardiac output increase by 40% (50% post birth).
Increase in the pulse (15%)
Increase in the stroke volume (35%)
Reduction in peripheral resistance (Drop in BP)
Why does cardiac output increase after birth?
The extra blood volume from the placenta is returned to the general circulation, up to 500ml.
Risk of overload
What causes haemodilution in pregnancy?
The plasma and haemoglobin and haematocrit do not increase by the same level - causing relative haemodilution
What are the effects on the coagulation system during pregnancy?
Increased clotting factors
Fibrinogen level rise by up to 50%
Decreased fibrinolytic activity
Decreased Anticoagulants (antithrombin, protein S)
Venous stasis (Decreased flow)
Risk of Venous Thromboembolism
What observation changes would you expect to see for pregnant patients?
Heart Rate: Increase of 10 – 20 bpm
Blood Pressure : Can decrease by 10 – 15 mmHg by 20 weeks
What is the ideal rate and duration of contractions for imminent birth?
2-3 minutes between the start of each contraction
Contractions lasting 60-90 seconds
When specifically should you start encouraging the mother to pant during delivery, why?
From the point of crowning to the delivery of the rest of the head.
This encourages slow delivery of the head and can help prevent perineum tear
What is the definition of antepartum haemorrhage (APH)?
Any bleeding from the genital tract after 24 weeks gestation prior to the birth of the baby
What is the difference between primary and secondary PPH?
Primary PPH: Occurs within first 24 hours following delivery > 500ml blood loss after vaginal delivery
Secondary PPH: Abnormal bleeding from the genital tract between 24hours and 12 weeks postnatally
What are the causes of APH?
Placenta Praevia (30%)
Placental Abruption (22%)
Abnormally Invasive Placenta (AIP)
Bleeding from genital track
Vasa praevia (rare)
Unexplained
What can cause PPH?
Tone - uterus not contracting (80%)
Trauma
Tissue
Thrombin
What is the general management of APH?
ACCESS, O2 AND DIESEL
Position patient in left lateral position to avoid aortocaval compression.
ABCDE assessment
Give oxygen to achieve sats >96%
IV access and IV fluids
Measure blood loss (Collect incos/pads etc. with blood in a clinical waste bag- bring them with you)
Transfer to the nearest obstetric unit
What is the management of PPH?
Measure blood loss (Collect incos/pads etc. with blood in a clinical waste bag- bring them with you)
ABCDE assessment
IV access
Uterine Massage (for atony)
Give Uterotonics (syntometrine)
Give TXA
IV fluids
Apply pressure to trauma
Bimanual Uterine Compression
Why must you have a high index of suspicion when taking observations of patients with APH or PPH?
Initial observations during Obstetric Haemorrhage may be falsely reassuring. Pulse rate and blood pressure are often maintained until 30% of circulating volume is lost in the pregnant population.
Bleeding may be concealed. If in doubt, treat as a PPH.
What are the definitions of gestational hypertension, pre-eclampsia and eclampsia?
Gestational Hypertension (GH)
Hypertension that develops on or after 20 weeks gestation without new proteinuria
Pre-eclampsia (PET)
GH with significant proteinuria. Increasingly, it is recognised that pre-eclampsia may present with hypertension or proteinuria (but not both) in association with other maternal multi-organ involvement or fetal compromise
Eclampsia
A convulsive condition associated with pre-eclampsia
What is the general management for eclampsia?
Correct patient positioning
Airway management
Maintain oxygen delivery
Minimise the risk of aspiration
IV Access
Treating the seizure
Controlling hypertension
Transfer to the nearest obstetric unit
Apart from blood pressure, what are the features of pre-eclampsia?
Ongoing or recurring severe headaches
Visual disturbances
Nausea or vomiting
Epigastic pain
Oliguria
Signs of clonus
Progressive deterioration in lab blood tests
Foetal growth restriction or abnormal doppler findings
What are the possible complications of pre-eclampsia?
Risk of stroke from HTN
Hepatic issues (liver oedema, failure, HELLP)
Renal (Glomular endothelial swelling, proteinuria, acute kidney injury)
Haematological (Endothelial damage, capillary leakage, clotting disorders)
CNS (Cerebral oedema, CVA)
Increased risk of pulmonary oedema
Retinal detachment
How soon after cardiac arrest should a perimortem cesarean scetion be performed?
Within 4 minutes
Why is a perimortem c-section performed?
Removing the foetus assists maternal BP
-improved diaphragmatic movement
-decreased IVC compression and vasodilatation
RH performed primarily in order to try and prolong maternal life
-The foetus is a secondary consideration
How long after birth should a healthy baby take its first breath?
Within 60-90 seconds
What is vena cava syndrome, how can it be avoided?
Compression of the vena cava in pregnant patients due to the weight of the uterus and foetus.
Left lateral position
