Abnormal labor and abnormal uterine contractions (dystocia) Dr Samar Sarsam.
Normal Labor and Delivery Valerie Robinson D.O.. Definition of Labor Contractions Become regular...
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Transcript of Normal Labor and Delivery Valerie Robinson D.O.. Definition of Labor Contractions Become regular...
Definition of Labor
• Contractions• Become regular• Increase in strength and frequency
• Cervical change: Dilation and Effacement• Normal is >1.2cm/hour in P0, >1.5cm/hour in P>0• 0% effacement is 3-4cm thick
• ROM may be spontaneous or assisted• 3 factors affecting successful labor and delivery are the
Power, Passenger, and Passage
3 Stages
• #1: Onset to full Dilation• #2: full Dilation to Delivery• Mom wants to bear down• May feel rectal pressure• May have N/V
• #3: Delivery to Placental expulsion
4 Phases
• Latent – Onset of labor and slow cervical dilation• Active – Rapid cervical dilation. Usu begins at 2-4 cm• After• Involution – Empty uterus contracts to become smaller
and hard. Stops bleeding.
Power
• Tocodynamometer (TOCO) measures length and strength of contractions
• May also use IUPC after ROM• Adequate contractions for labor are 3-5 per 10 minutes
Passenger
• Size• Presentation: breech, vertex, transverse• Position: LOA, etc• Movements• FHR• How many babies are there?
7 cardinal movements
• Engagement – widest diameter is below pelvic inlet• Descent• Flexion• Internal Rotation – rotation into the AP dimension• Extension – occiput contacts the pubic symphysis• External Rotation – head rotates to correct anatomy• Expulsion
Fetal heart monitor
• Baseline – average FHR over 10 minutes. 110-160• Variability – Fluctuations in FHR amplitude• Absent• Minimal - <5 BPM• Moderate - 6-25 BPM• Marked - >25 BPM
• Accelerations – increase from baseline• Normal is a 15 BPM increase lasting at least 15 seconds, <2 minutes• If it lasts >10 minutes, it is a baseline change
• Decelerations – decrease in FHR with return to baseline• Early• Late• Variable• Prolonged - >2 minutes
Initial Assessment
• Check cervical D/E/S• Dilation: 0-10 cm• Effacement: 0-100%• Station: – 5-+5cm above-below ischial spines
• Check presentation and position• Check for ROM; color and quantity• Check vitals• Apply TOCO and Doppler transducer• Review prenatal chart
L&D Care
• IV fluids are not necessary• IV access should be gained for emergency, labor
augmentation, antibiotics• Restriction of drink is not necessary, but food may be
restricted due to risk of aspiration pneumonitis• Pain control• Encouragement and reassurance• An anterior cervical lip lasting >30 minutes may be
normal or may indicate a malposition
Delivery
• Nurse or doctor will check labor progression by monitoring TOCO and checking Dilation/Effacement/ Station
• Allowing passive descent instead of pushing at 10cm increased chance of SVD, decreased chance of instrument assistance, decreased pushing time
• Pushing: Reflexive, or Valsalva. 10x3 in contraction• May use hands to support the perineum or fetal head and
reduce risk of tearing.• May do a manual reduction of an anterior cervical lip• Episiotomy is only used when there is a risk of severe
perineal laceration• Watch for and reduce a nuchal cord
Delivery cont.
• Deliver anterior shoulder, use downward traction on the head in concert with contractions
• Then upward traction to deliver posterior shoulder• Suctioning may be performed but has not been shown to
have any benefit except in babies with obvious secretory obstruction or who will be on a ventilator
• Cord clamping can take place immediately, but there is some benefit to delaying it so the placenta can deliver more blood to the baby. 75% of available blood is transfused in the first minute following delivery.
• Cord blood can be collected for diagnostic purposes• Cord blood pH is measured by needle aspiration of artery
Stage 3
• Uterus contracts, placenta separates, cord lengthens• WHO suggests that placenta is retained after 1 hour• Retained placenta increases risk of hemorrhage• More commonly retained in preterm delivery• Active management includes: Prophylactic oxytocin, Cord
traction, and Uterine massage• When providing cord traction, support the fundus to prevent
inversion
• Slowly rotate the placenta as it is delivered, so you can get the attached membranes out intact.
References
• Costanzo, Linda S. Physiology. 3rd Ed. Saunders/Elsevier: Philadelphia, PA. 2007. pp. 456-460
• Gordon, John David MD, Et al. Obstetrics, Gynecology, and Infertility: Handbook for Clinicians. 6th Ed. Scrub Hill Press: Arlington, VA. 2007. pp 87-88.
• http://www.gynaeonline.com/perineal_tear.htm• Funai Et al. Management of normal labor and delivery.
UpToDate. Updated 5/18/12.• Funai Et al. Mechanism of normal labor and delivery.
UpToDate. Updated 10/19/11.