1st Stage of Labour Flashcards
What are the stages and phases of labour?
Latent phase
Active 1st stage
Rest and thankful phase
Active 2nd stage
3rd stage
4th stage
When does oxytocin flow best according to Nolan 2020?
When women feel safe, when privacy is guranteed and when they are unobserved
When and where is oxytocin released from in labour?
Released from the posterior pituitary lobe into the circulation
Released in pulses with increasing frequency and amplitude in the first and second stages of labour
A few pulses released in the third stage of labour
During labour, the fetus exerts pressure on the cervix of the uterus, which activates a feedforward reflex, which releases oxytocin.
What is the problem with Friedman’s work (Friedman’s trajectory)
Friedman was an American obstetrician in the 1950s. His research all took place on white women (middle class, similar ages, supine position), where he tried to find out the labour trajectory. He plotted it on a graph (Friedman’s curve) which estimated the length of each stage of labour.
What do the NICE guidelines describe can be descriptions of the 1st stage of labour
there are contractions and
there is some cervical change, includin cervical position, consistency, effacement and dilation up to 4cm.
What happens to the endocrine in the onset of labour?
Progesterone withdrawal
What happens to the immune in the onset of labour?
Leukocyte and leukotriene activation
What happens in terms of mechanical factors in the onset of labour?
Enhanced uterine stretching and amnio-chorionic membrane disruption.
What do the endocrine, immune and mechanical factors cause in the onset of labour?
An inflammatory activation and protaglandin production to transform the myometrium to an active contractile state at term.
What does progesterone activate?
Prostaglandins which aids the mechanical process
What does activated leukocytes cause?
Inflammatory response aiding the mechanical process.
How does labour start in terms of progesterone withdrawal?
The mechanisms that supress progesterone’s function near term to allow labour an delivery are still shrouded in uncertainty.
A hypothetic scheme of the mechanisms that control progesterone reposnsiveness in teh pregnant human myometrium
What do the placental oestrogens, relaxin and prostogalndins do? (Fuchs et al 1991)
Soften the collagen fibres in the cervix and make it more distensible
How is uterine tissue prepared for labour?
Under the influence of oestrogen, prostoglandins and distension of uterine tissue, uterine tissue is prepared for labour through cell multiplication and hypertropjy (increase in size of cells)
What helps stimulate contractions?
Uterotrophins, including oxytocin, raise levels of intracellular calcium
What else is oxytocin secreted by that is a major contributor to inc oxytocin levels in uterine tissue
fetus
Due to the influence of oestrogens, what does the number of gap junctions in the muscles increasing cause?
Allows inccreased coordination of myometrial contractility
What are gap junctions?
Transcellular membrane channels which allow ion exchange between cells to propagate an electrical signal and subsequent muscle contractions.
what do the NICE guildines say about assessment of women in 1st stage of labour?
-When performing an initial assessment of a women in labour, listen to her story and take into account her preferences and emotional and psychological needs.
-Carry out initial assessment to determine if midwifery-led care in any setting is suitable for the woman, irrespective of any previous plan including consultant led care
what are maternal factors to consider?
Review and discuss the antenatal notes (including all antenatal screeningresults).
* Review the personalised care plan.
* Review if there are any antenatal or intrapartum risk factors for fetal hypoxia
* Ask about the length, strength and frequency of contractions.
* Ask about any pain they are experiencing and discuss options for pain relief.
* Record pulse, blood pressure, temperature and respiratory rate, and carry outurinalysis.
* Record if any vaginal loss.
* Check if needs intrapartum antibiotics for group B streptococcus prophylaxisand, if so, that these are available in chosen place of birth if needed
What do the NICE 2023 guidlines say about transfer to obsetetric based care in regards to bp
A single reading of either raised diastolic blood pressure of 110 mmHgor more, or raised systolic blood pressure of 160 mmHg or more －either raised diastolic blood pressure of 90 mmHg or more or raisedsystolic blood pressure of 140 mmHg or more on 2 consecutivereadings taken 15 to 30 minutes apart
What do Marshall and Raynor say about low and high blood pressure
Hypotension may be caused by being in a supine position, by shock or as a result of vasodilation associated with epidural
Hypertension is an indicator of pre-eclampsia
Labour may further elevate bp
What are the observations of the unborn baby upon arrival
Ask about the baby’s movements in the last 24 hours.
* Palpate the woman’s abdomen to determine the fundal height, the baby’s lie, presentation,position, engagement of the presenting part, and frequency and duration of contractions.
* Auscultate the fetal heart rate for a minimum of 1 minute immediately after a contraction;palpate the woman’s pulse to differentiate between the heartbeats of the woman and thebaby.
* Carry out intermittent auscultation immediately after a palpated contraction for at least1 minute, repeated at least once every 15 minutes, and record it as a single rate on aportogram and in the woman’s notes (NICE 2022: Fetal monitoring in labour)
* If there is uncertainty about whether the woman is in established labour, a vaginal examinationmay be helpful after a period of assessment, but is not always necessar
What to consider when conducting a VE
Be sure that the examination is necessary and will add important information to the decision-making process.
* Recognise that a vaginal examination can be very distressing for a woman,especially if she is already in pain, highly anxious and in an unfamiliarenvironment.
* Explain the reason for the examination and what will be involved.
* Ensure the woman’s informed consent, privacy, dignity and comfort.
* Explain sensitively the findings of the examination and any impact on the birthplan to the woman and her birth companion(s).* Advise the woman that she can decline the examination before it starts, or askto stop at any stage during the examination.
