This document discusses the physiology of labor and anesthesia during labor. It begins by defining labor as the process by which regular uterine contractions cause cervical dilation, usually resulting in fetus delivery after 22 weeks of pregnancy. Labor involves extensive physiological changes in the mother to allow fetus delivery through the birth canal. The document then covers classifications of labor, theories of labor onset, signs that precede labor, methods for assessing cervical readiness, characteristics of uterine contractions and labor stages. It discusses pain management techniques during labor, including non-medical and medical methods. The document provides details on various anesthesia techniques for labor like local infiltration and epidural anesthesia.

1. Physiology of labor.
Anesthesia in labor

2. LABOR–is the physiology process whereby
regular uterine activity causes progressive
cervical dilatation and usually results in
delivery of the fetus, after 22 weeks of
pregnancy.

3. - Labor is a physiologic process that
permits a series of extensive physiologic
changes in the mother to allow for the
delivery of her fetus through the birth
canal.
- It is defined as progressive cervical
effacement, dilatation, or both, resulting
from regular uterine contractions that occur
at least every 5 minutes and last 30-60
seconds.

4. Classification of labor
 PRETERM LABOR– delivery the fetus from
the cavity of uterus in 22-36 weeks of
pregnancy.
 TERM LABOR- delivery the fetus from the
cavity of uterus in 37-42 weeks of
pregnancy.
 Delayed labor- delivery the fetus from the
cavity of uterus after 42 weeks of
pregnancy.

5. Theories, which explain the
mechanism of birth
beginning
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Mechanical
Immune
Placenta
Chemical
Endocrine
Modern

6. Forerunners of labor

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The bottom of uterus is lowering
Insertion of pre-lying part
Krestellers cork is going away.
Reductions of woman’s weight.
Irregular muscular contractions of
uterus.
 Maturity of uterus’s cervix

7. BISHOP’S SCALE
Signs
Score
0
1
2
Consistency of
uterus’ cervix
Thick
Softened, but thick in
the area of internal os
Soft
Length and
effacement of cervix
More than 2 сm
1-2 сv
Less than 1 cm or
effaced
Permeability of
cervical canal or
cervical os
External os is closed
or lets pass trough
fingertip only
Cervical canal lets pass
one finger freely.
Internal os is still
present
Cervical canal lets
pass more than
one finger freely. If
the cervix is
effaced – dilatation
more than 2 cm
Disposition of the
cervix
Posterior
Anterior
Medial
0-2 points – uterus’ cervix is “immature”
3-4 points – cervix is “mature but not enough”
5-8 points – cervix is “mature”

8. Cervical effacement in
nullipara women

9. Cervical dilataton in
multipara women

10. Physiological Preliminary
period
Characteristics:
1. Irregular uterine contractions.
2. There are no structure changes in the
cervix of uterus.
3. Duration 6-8 hours

11. Labor begins with
 Regular muscular contractions.
 Cervical effacement.
 Forming of amniotic vial.

12. Forewaters

13. Labor stages
 І stage (cervical) – dilatation of the cervix
(12-15 hrs.)
 ІІ stage (pelvic) – starts from complete
dilatation of cervix to the delivery of baby
(1-2 hrs.).
 ІІІ stage (placental)- starts from the birth
of baby till delivery of the placenta. (5-30
min.).

14. The first period of labor

15. Uterine contractions – regular
contractions of uteri musculature.
Typically, contractions occur every 5-10
minutes and last for 20-25 seconds in the
onset of labor.
As labor progresses, the contractions
become more frequent, more intense,
and last longer.

16. Characteristics of uterine
contractions
 Tonus – minimal pressure between contractions –
10-12 mm Hg.
 Intensivity – difference between amplitude and
basal tonus of uterus 30-50-70 mm Hg.
 Frequency per 10 min – 3-4 за 10 хв.
 Duration – 35 - 93 сек.
 Rhythm - intervals between contractions – equal.
 Activity = intensivity х frequency per 10 min = 280340 Montevideo units

17. The second stage of labor

18. Bearing-down efforts
(or pushing)
 Is the periodic contractions of diaphragm,
pelvic floor muscles and front abdominal
which are add to the force of uterine
contractions.

19. The birth canal

20. Record methods of labor
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Tocography (external and inernal)
Radiotelemetry.
Electrogisterography.
Cardiotocography.

21. Friedman’s curve
А – dynamic of cervical effacement
Б – advancement of the presenting part of fetus

22. The partogram

23. Cardiotocography

24. Cardiotocography

25. Fetal blood sampling

26. Types of placenta separation

27. Shreder’s sign

28. Kustner’s sign
а)
б)

29. Methods of obtainment of the
separated placenta (afterbirth)
 Abuladze.
 Genter.
 Krede-Lazarevich.

30. Method of Abuladze

31. Genter’s Method

32. Krede-Lazarevich’s method

33. Examination of placenta and
membranes

34. Manual separation of
placenta

35. Anesthesia in Labor
Causes of labor pain:
- Hypoxia of uterine muscle
- Stretching of the uterus’ lower
segment
- Stretching of the uterus’ ligaments
- Psychological causes

36. Modern methods of the pain relief:
-Non-medicamental
-Medicamental

37. Psychological training of
pregnant women
-Decreases phychological component
of pain
-Decreases fear of labor
-Forms correct imagination about
labor in patient

38. Lessons
 1 lesson– anatomy and physiology, changes
during pregnancy
 2 lesson– 1st period of labor, correct
behaviour of patient, role of partner;
 3 lesson– 2nd and 3rd periods of labor;
 4 lesson – port-partum period, breast
feeding, caring of baby;
 5th lesson - revision.

39. Medicamental pain relief must have
 Good effect
 Simplicity of usage
 Safety for mother and fetus!

40. Indications to Anesthesia:
 No effect from the psychoprophylaxis;
 Gestoses of the second half of pregnancy
 Hard extragenital patology
 Operative interferences ;
 Labor abnormalities

41. Conditions
 Regular uterine contractions
 Cervical dilation 4 cm+
 Absence of contraindications

42. Drugs:
 Promedol 1% - 1 ml
 Sibasone 0,5% - 2 ml

43. Epidural anaesthesia

44. Epidural anaesthesia

45. Epidural anaesthesia

46. Epidural anesthesia
 Anatomical abnormalities, such as spina bifida or scoliosis
 Previous spinal surgery (where scar tissue may hamper the
spread of medication, or may cause an acquired tethered spinal
cord)
 Certain problems of the central nervous system, including multiple
sclerosis or syringomyelia
 Certain heart-valve problems (such as aortic stenosis, where the
vasodilation induced by the anaesthetic may impair blood supply
to the thickened heart muscle.)
 Bleeding disorder (coagulopathy) or anticoagulant medication (e.g.
warfarin) - risk of spinal cord-compressing hematoma Infection
near the point of intended insertion Infection in the bloodstream
which may "seed" via the catheter into the (otherwise relatively
impervious) central nervous system
 Uncorrected hypovolemia (low circulating blood volume)

47. Local anaesthesia
 Infiltrative anaesthesia
(episiotomy, reparation of
perineum
 Lidocain2% 4-10 ml is used

48. Thank you!