Physiological Adaptations Normal Labor and Delivery Physiological Adaptations Chapter 17 Presented by Ann Hearn

LABOR The process by which the products of conception are expelled from the body

UTERINE CONTRACTIONS Contraction - exhibits a wavelike pattern that begins slowly climbing (increment) to a peak (acme), and decreases (decrement) Intensity - strength of uterine contraction acme Define the characteristics of uterine contractions. P. 318 Decrement Increment

Uterine Contractions 2. Define the following terms related to uterine contractions: a. frequency b. duration c. intensity d. interval Duration- from beginning of one contraction to the end of the same contraction Frequency- from beginning of one contraction to the beginning of another contraction Interval - resting time between contractions allows for placental perfusion

Uterine Contraction - review

Assessment of Contraction 1. Subjective symptoms by woman 2. Palpation and timing by the nurse 3. Use of Electronic Fetal Monitor (EFM)

Opposing Features of Uterine Activity Upper 2/3 of uterus contracts actively Lower third and cervix are passive 1. b. uterine activity is characterized by opposing features, explain. These lead to downward progression of fetus with each contraction

Uterine Muscle

CERVICAL ASSESSMENT Dilation: the size of the cervical opening (measured in centimeters). Full dilation = 10cm Effacement:–estimated amount the cervix has thinned (measured in percent) Complete effacement = 100% 3. Define the following terms related to cervical changes during labor: p. 319 a. effacement b. dilation

Myometrial Activity Effacement- thinning of the cervix (%) Dilation – enlargement and widening of the os (cm) 4. How are cervical dilation and effacement measured? P. 320

Cardiovascular System Changes During each contraction, blood flow to the placenta gradually decreases, resulting in an increase in the woman’s blood volume causing her B/P to increase and slowing of her pulse. Because these changes occur during a contraction, it is best to assess vital signs between contractions. 2. Why is it best to assess the mother’s vital signs during the interval between contractions?

Respiratory System Changes During labor a woman is likely to hyperventilate causing: Tingling in hands and feet Numbness Dizziness 3. What are nursing interventions to alleviate hyperventilation during labor? Have the woman slow her breathing, breath into her hands or a paper bag.

Gastrointestinal System Changes Most woman are limited to clear liquids or NPO during the labor process. Gastric motility and digestion of food is reduced. Decrease risk of aspiration Why? 4. Why is a woman placed on clear liquids or NPO during labor?

Urinary System Changes Reduce sensations of needing to void Intense contractions Anesthesia Unaware of having a Full bladder 5. Why is the woman prone to a full bladder? What are the consequences of a full bladder during labor? Inhibit fetal descent or (increased discomfort if no anesthesia)

Hematopoietic System EBL = Estimated blood loss Vaginal delivery ~ 500ml cesarean birth ~1000ml Clotting factors are elevated and Fibrinolyis is decreased to promote coagulation at the placental site

Passenger Essential Factors in Labor Powers Passageway Psychological

THE POWERS

Major Powers Involved Primary Force: Secondary Force: Involuntary Uterine Contractions or Muscular contractions which lead to dilation and effacement in the First Stage of Labor Secondary Force: Voluntary Uterine Contractions or Abdominal muscles assist in the Second Stage of Labor with pushing. Increase intra-abdominal pressure to aid in expulsive forces 5. What are the primary and voluntary forces of labor? P.3 18

THE PASSAGEWAY

THE PELVIS Determine if the pelvic cavity is of adequate size to allow for the passage of the full term infant Optimum shaped pelvis is Gynecoid See pg. 322 for pelvic shapes.

THE PELVIS False Pelvis True Pelvis Represents Supports the weight of the uterus Shallow basin above the inlet or brim True Pelvis Represents the bony limits of the birth canal 6. Differentiate between the terms true pelvis and false pelvis. p. 322 & 323

True Pelvis vs False Pelvis Inlet - upper margin of symphysis pubis to the upper margin of sacrum Midpelvis - level of the ischial spines Outlet - Lower pubic bone to tip of coccyx. This area is the smallest portion that the baby must travel through. 7. Differentiate between the inlet, the midpelvis, and the outlet of the true pelvis?

Station- degree that the presenting part has descended into the pelvis in relationship to ischial spines. Goal: Move from – to + stations 9. What is station? How is station determined and measured? Does the station need to be a + or – for delivery?  

Engagement Descent of the fetal presenting part in relation to the ischial spines of the maternal pelvis = 0 station.

Engagement Engagement -largest diameter of presenting part has passed through the pelvic inlet Assessed during vaginal exam Ballotable 8. What is engagement? How is it determined? Engaged

THE PASSENGER And PPRESENTATION

Fetal Head Because of its size and rigidity, the fetal head has a major impact on delivery. The bones are not firmly united. There are sutures between the bones that allow them to overlap or MOLD to the birth canal. Head also can rotate, flex, and extend 8. Compare the bones, suture lines and fontanels of the fetal head. What do the bones of the fetal head do to accommodate the birth canal? p. 324.

Fetal Lie Relationship of the long axis of the fetus to the long axis of the mother. Longitudinal Lie Transverse Lie 9. Define the term "fetal lie". What is the difference between transverse lie and longitudinal lie. Which is the most favorable for a vaginal delivery? P. 324

Attitude Relationship of fetal body parts to each other Optimum attitude is flexion or ovoid 10. What is fetal attitude? What is the normal fetal attitude? p. 324

Fetal Presentation The portion of the fetus that enters the pelvis first Three Types: Cephalic Breech Shoulder 11. Define the term "fetal presentation" and explain the difference between the following presentations: p. 325. cephalic presentation Vertex Military Brow Face breech presentation

Reference Points of Presentation Cephalic = Head Vertex, Military, Brow, Face Breech = Buttock or Foot Frank, Full, Footling Shoulder = Transverse lie p. 325

Cephalic Presentations

Breech Presentations

Position 12. What is fetal position? Explain the position indicated by the letters: p. 325 & 325 LOA ROA LOP ROP Fetal position describes the location of the fixed reference point on the presenting part in relation to the four quadrants of the maternal pelvis. R= right, L= left, O= occiput, A=anterior, P=posterior. 13. What is the reference point for a vertex presentation? Occiput 14. What is the reference point for a breech presentation? Sacrum

Position Relationship of the Fetal Presenting Part to the Maternal Pelvis Steps: 1. Determine the Presenting Part 2. Divide the mothers pelvis into 4 imaginary quadrants A 12 R L 9 3 6 P

Test Yourself Overlapping of the fetal skull to facilitate its passage through the bony pelvis is ___________. Relationship of fetal body parts to each other is_____________. Head first presentation is_________________. Relationship of the fetal spine to the maternal spine is ________________. Term that refers to the part of the fetus that enters the pelvic inlet first is _____________.

THE PSYCHOLOGICAL

BREAK THE CYCLE ! FEAR TENSION PAIN 15. How does anxiety, fear, and fatigue physiologically affect the process of labor? P. 389-391 PAIN

CAUSES OF LABOR Increase in Estrogen Decrease in Progesterone Page 328 High levels of Prostaglandins Degeneration of Placenta Over-distention of Uterus

Premonitory Signs of Labor The impending signs that take place the last several weeks of pregnancy or even the last several days Pg. 328 & 329

Premonitory Signs of Labor Lightening False Labor Pain (Braxton Hicks) Bloody Show Increased clear vaginal secretions Small weight loss (~3 pounds) Sudden increase in energy

True vs False Labor TRUE LABOR FALSE LABOR Contractions are: * Irregular * No change or decrease with walking * Contractions felt in abdomen above umbilicus: Braxton Hicks No change in cervix TRUE LABOR Contractions are: * Regular * Increase in intensity and duration with walking * Felt in lower back, radiating to lower portion of abdomen Dilation and effacement Fetus usually engaged Progressive changes in the cervix Pg. 329

Phases and Stages of Labor Stage 1: 0 - 10 cm. Phase 1 - Latent - dilate 0 - 3 cm. Phase 2 - Active - dilate 4 - 7 cm. Phase 3 - Transition - dilate 8 - 10 cm Stage 2: From complete dilation and effacement to delivery of the baby Stage 3: From delivery of baby to the delivery of the placenta Stage 4: the first hour after delivery 21. Define the first stage of labor. P. 329. 22. What are the three phases of the first stage of labor? 23. What are the characteristics of each of each of these three phases in terms of cervical dilation, uterine contractions, and maternal behavior?

Signs of Second Stage of Labor Complete dilatation of cervix Urge to bear down Perineum begins to bulge, flatten Increase in bloody show Rectal pressure Labia begins to part with each contraction 24. Define the second stage of labor and the maternal behavior associated with this stage. P. 333.

Mechanisms of Labor/ Cardinal Movements Descent Flexion Internal Rotation Extension External Rotation 25. Explain the positional changes /cardinal movements of stage 2 and why they occur in this order? Pg. 330 & 331 Expulsion

Signs of Stage Three of Labor Globular Shape of Uterus Fundus Rise in Abdomen Sudden Gush of Blood Protrusion of Umbilical cord 25. What is the third stage of labor and what are the signs that indicate placental separation? P. 333.

Placenta Fetal side (Schultze) Maternal side (Duncan)

Forth Stage of Labor Recovery period after delivery and bonding with the newborn. Last from 1- 4 hours. 26. Define the fourth stage of labor and the maternal behavior associated with this stage. P. 333.

When To Go To The Hospital Regular uterine contractions Rupture of Membranes (ROM) Red vaginal Bleeding Decreased Fetal Movement Other concerns

Nursing Care Establish Relationship Nursing Assessment: Maternal and Fetal Interview Interventions during labor and birth. Intrapartum assessment guide pg. 337-341

Leopold’s (1 of 4) Technique for Assessing Fetal Presentation and Position Standing on the right side, face the woman and palpate with the palms of the hands. Step 1 - Start at upper fundus and palpate for the head or buttocks Pg. 342

Leopold’s (2 of 4) Step 2 - Go down each side and locate smooth back or “lumpy” extremities.

Leopold’s (3 of 4) Step 3 - Gently grasp lower portion of uterus and feel for the head or buttock

Leopold’s (4 of 4) Step 4 - Turn and face the woman feet, using both hands palpate lower abd. for cephalic prominence or brow.

Ausculation Assess for the area of greatest intensity of the FHR. Usually best heard at the fetal back

Vaginal Examination Presentation – presenting part (head/buttock) Position – fetal head (OA, OP etc.) Dilation - enlargement & widening of os (cm) Effacement – thinning of the cervix (%) Condition of Membranes – ruptured or intact

Vaginal Examination – cont’d Station- degree that the presenting part has descended into the pelvis. Relationship to ischial spines (ballotable, -, 0, +) Engagement - largest diameter of presenting part has passed through the pelvic inlet

Amniotic Membranes Intact Ruptured Color Amount Odor SROM AROM Clear Yellow Meconium Amount Odor

Duration of Labor Resistance of the Cervix Presentation and position of the fetus The woman’s pelvis Preparation and relaxation of the mother Primigravida - up to 22 hrs; average 12 1/2 hrs Multigravida - 8 - 17 hrs; average 10 hrs.

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