4.2c Physiological Adaptation to Labor Flashcards
1
Q
Fetal Adaptation
A
2
Q
Fetal Heart Rate
A
- FHR monitor provides important information related to oxygenation
- Average heart rate is 140 bpm (110-160)
- Average 160bpm at 20 weeks of gestation
- Decreases progressively as baby reaches term
3
Q
Fetal Heart Rate Fluctuation Reasons
A
- Spontaneous movement
- Vaginal examination
- Fundal pressure
- Uterine contractions
- Abdominal palpations
- Fetal head compression
4
Q
Fetal Circulation
A
- Contractions during labor decrease circulation through spinal arterioles and perfusion
- Also affected by
- Maternal position
- Uterine contractions
- Blood Pressure
- Umbilical Cord Blood Flow
5
Q
Fetal Respirations
A
Preparations for breathing
- Fetal lung fluid is cleared from air passageways as fetus passes through birth canal
- Labor itself also absorbs some lung fluid
- PO2 Decreases
- PCO2 Increases
- Arterial pH decreases
- Bicarbonate decreases
6
Q
Maternal Adaptations to Labor
A
- CO increases 10-15% in 1st stage and 30-50% in second stage
- HR increases slightly in 1st and 2nd stage
- BP increases during contractions and returns in between (systolic increases more than diastole)
- WBC count increases
- RR increases
- Temperature may elevate
- Proteinuria may occur
- Gastric motility and absorption of solid food decrease
- n/v may occur during 1st to 2nd stage of labor
- Blood glucose decreases
7
Q
Cardiovascular Adaptations
A
- 300-500 mL of blood shunted from uterus to maternal vascular system with each contraction
- End of 1st stage of labor CO is 51% above baseline pregnancy
- CO peaks 10-30 min after birth (vaginal or c-section)
- CO returns to normal during 1st hour of postpartum
- Drop in HR accompanies increased CO
- BP Increases during contraction and normalizes in between
- Supine hypotension occurs when lying down
8
Q
Risk of Supine Hypotension
A
- Large fetus
- Multifetal pregnancy
- Maternal medications
- Polyhydramnios (too much amniotic fluid)
- Obesity
- Dehydration
- Hypovolemic
9
Q
Respiratory
A
- Increased RR due to increased physical activity Hyperventilation may cause - Respiratory alkalosis - Hypoxia - Hypocapnia
Unmedicated patients second stage of labor oxygen consumption doubles
Anxiety increases oxygen consumption
10
Q
Renal
A
- Spontaneous voiding difficult due to tissue edema caused by
- Pressure from presenting part
- Discomfort
- Analgesia
- Embarrassment
- Diaphoresis
- Proteinuria (normal finding, caused by breakdown of muscle tissue from physical labor)
11
Q
Integumentary
A
- Distensibility (stretching) in vaginal introitus
- Minute tears around vaginal introitus may occur
12
Q
Muscoloskeletal
A
- Backache
- Joint Aches
13
Q
Neurologic
A
- Initially patient may be euphoric
- After there is increased seriousness
- Amnesia between contractions during second stage
- Fatigue after birth
- Endogenous endorphins raise pain levels and produce sedation
- Physiologic anesthesia of peritoneal tissue decrease perception of pain
14
Q
Gastrointestinal
A
- Motility and absorption of food decreased
- Stomach emptying time slowed
- n/v is common
- Diarrhea at onset of labor
- May be hard impacted stool in rectum
15
Q
Endocrine
A
- Labor caused by decreased progesterone, increased estrogen, prostaglandins, oxytocin
- Metabolism increases
- Glucose decreases
- Fatigue
- Increased temperature
