1. Physiology of Normal Labour and Childbirth
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Physiology of Normal Labour and Childbirth
For you assessment you are required to revise those slides with white background. Slides with black ground would give you an idea about few practical aspects of childbirth and care of a woman in labour.

2. Parturition Estrogen in late pregnancy:
Stimulates production of oxytocin receptors in myometrium.
Produces receptors for prostaglandins.
Produces gap junctions between myometrium cells in uterus.
Factors responsible for initiation of labor are incompletely understood.

5. Parturition

7. Parturition Fetal adrenal cortex: Uterine contractions:
Chain of events may be set in motion through CRH production.
Fetal adrenal zone secretes DHEAS, which travel from fetus and placenta.
Uterine contractions:
Oxytocin.
Prostaglandins.

9. Labour Pain Variation in pain perception between individuals
Why do these different perceptions of pain exist
How do midwives respond to different expression of pain
Increased reports of pain may indicate complication
Culture
Personality
Past experience
Low pain threshold
Anxiety
Learned behaviour

10. Pain in Labour C-fibres Uterine smooth muscle A-delta
traction and pressure on the peritoneum, uterine ligaments, urethra, bladder, rectum, lumbosacral plexus, fascia and muscles of the pelvic floor
Labour pain is the result of many complex interactions, physiological and psychological, excitatory as well as inhibitory.
Pain during the first stage of labour is due to distention of the lower uterine segment,
mechanical dilatation of the cervix and lastly due to stretching of excitatory nociceptive afferents resulting from the contraction of the uterine muscles1.
The severity of pain parallels with the duration and intensity of contraction2.
In the second stage additional factors, such as traction and pressure on the parietal peritoneum,
uterine ligaments
urethra, bladder,
rectum, lumbosacral plexus, fascia and muscles of the pelvic floor increase the intensity of pain.

11. The uterus and cervix are supplied by afferents accompanying sympathetic nerves in the uterine and cervical plexuses, the inferior, middle and superior hypo gastric plexuses and the aortic plexus.
The small unmyelinated 'C' visceral fibres3 transmit nociception through lumbar and lower thoracic sympathetic chains to the posterior nerve roots of the 10th, 11th and 12th thoracic and also to 1st lumbar nerves to synapse in the dorsal horn4.
The chemical mediators involved are bradykinin, leukotrienes, prostaglandins, serotonin, substance P and lactic acid5.
As the labour progresses severe pain is referred to the dermatomes supplied by T10 and L1.
In the second stage, the direct pressure by the presenting part on the lumbosacral plexus causes neuropathic pain. Stretching of the vagina and perineum results in stimulation of the pudendal nerve (S2,3,4) via fine, myelinated, rapidly transmitting 'A delta' fibres3. From these areas, the impulses pass to dorsal horn cells and finally to the brain via the spino-thalamic tract

12. A tool that could be used for pain assessment
(Linda Husband-caring for the person with pain in FUNDAMENTAL NURSING PRINCIPLES AND SKILLS 474)

13. Partograph and Criteria for Active Labor
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Label with patient identifying information
Note fetal heart rate, color of amniotic fluid, presence of moulding, contraction pattern, medications given
Plot cervical dilation
Alert line starts at 4 cm--from here, expect to dilate at rate of 1 cm/hour
Action line: If patient does not progress as above, action is required
The partograph is a useful tool for monitoring the progress of labor. Use it to avoid unnecessary interventions so maternal and neonatal morbidity are not needlessly increased, to intervene in a timely manner to avoid maternal and neonatal morbidity or mortality and to ensure close monitoring of the woman in labor.
At the alert line, the onset of the active phase of labor (4 cm), the patient is expected to reach full dilation at the rate of 1 cm/hour. At the action line, which is 4 hours to the risk of the alert line, the practitioner is signaled to take action if the patient is not following the expected course of labor.

14. Clean Delivery Infection accounts for 14.9% of all maternal deaths
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Clean Delivery
Infection accounts for 14.9% of all maternal deaths
These deaths can be avoided with infection prevention practices
Also refer to the HIV set.

15. Infection prevention practices
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Infection prevention practices
Use disposable materials once and decontaminate reusable materials throughout labor and childbirth
Wear gloves during vaginal examination, during birth of newborn and when handling placenta
Wear protective clothing (shoes, apron, glasses)
Wash hands
Wash woman’s perineum with soap and water and keep it clean
Ensure that surface on which newborn is delivered is kept clean
High-level disinfect instruments, gauze and ties for cutting cord
These principles apply to all levels of care.

16. 4/24/2017
Support of woman
Give woman as much information and explanation as she desires
Provide care in labor and childbirth at a level where woman feels safe and confident
Provide empathic support during labor and childbirth
Facilitate good communication between caregivers, the woman and her companions
Continuous empathetic and physical support is associated with shorter labor, less medication and epidural analgesia and fewer operative deliveries
Data show that emotional and physical support reduce the complications of labor, such as the need of analgesia and operative interventions.
WHO 1999.

17. Best practices: last stage of labour
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Best practices: last stage of labour
Active management of third stage for ALL women:
Oxytocin administration
Controlled cord traction
Uterine massage after delivery of the placenta to keep the uterus contracted
Routine examination of the placenta and membranes
22% of maternal deaths caused by retained placenta
Routine examination of vagina and perineum for lacerations and injury
WHO 1999.

18. Best Practices: Postpartum
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Best Practices: Postpartum
Close monitoring and surveillance during first 6 hours postpartum
Parameters:
Blood pressure, pulse, vaginal bleeding, uterine hardness
Timing:
Every 15 minutes for 2 hours
Every 30 minutes for 1 hour
Every hour for 3 hours

19. Practices Used for Specific Clinical Indications
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Practices Used for Specific Clinical Indications
Bladder catheterization
Operative delivery
Oxytocin augmentation
Pain control with systemic agents
Pain control with epidural analgesia
Continuous electronic fetal monitoring

20. Best Practices: Labour and Childbirth
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Best Practices: Labour and Childbirth
Use non-invasive, non-pharmacological methods of pain relief during labor (massage, relaxation techniques, etc.):
Less use of analgesia OR 0.68 (CI 0.58–0.79)
Fewer operative vaginal deliveries OR 0.73 (95% CI 0.62–0.88)
Less postpartum depression at 6 weeks OR 0.12 (CI 0.04–0.33)
Offer oral fluids throughout labor and childbirth
Non-invasive, non-pharmacological pain relief reduces the need for pharmacological/lower dose needed.
Neilson 1998.

21. Lactation Hypothalamus releases PRH.
Anterior pituitary releases prolactin:
Stimulates milk production.
Prolactin secretion primarily controlled by PIH.
Oxytocin needed for “milk letdown.”

22. Lactation Mammary gland:
Lobules contain glandular alveoli that secrete milk of the lactating female.
Alveoli secrete milk into secondary tubule that converge to form mammary duct.
Ampulla:
Where milk accumulates during nursing.
Neuroendocrine reflex:
Act of nursing maintains high levels of prolactin.
Sucking may cause release of PRH.

23. Milk-Ejection Reflex
Insert fig

24. Write a short story about oxytocin. This should include:
A question which will be certainly in my list of questions this year or next year
Write a short story about oxytocin.
This should include:
History of discovery of oxytocin
Its chemistry
Its physiological action in childbirth and its other physiological functions
Its uses in clinical practice