Whelping and Dystocia Flashcards
What is Dystocia?
Difficult birth
Life threatening for mother and offspring
5% of all pregnancy
Dystocia
Prevention
Breeding soundness examination
Good BCS
Dystocia
What breed is it more frequent in?
Brachycephalic - just do a C-section
Dystocia
What is important to determine? How?
Delivery date!
How:
LH surge: 65 +/- 2 days
Ovulation: 63 +/- 2 days
Fertilization: 60 +/- 2 days
What induces labor?
Increasing prostaglandin F2alpha and fetal cortisol
Small vs. large litters
Small: will have prolonged gestation, causing them to grow beyond normal size
Large: may shorten gestation (more cortisol produced b/c more fetuses)
Note cat gestation not effected by this
Progesterone and Labor
Late gestation: pregnancy maintained by progesterone level above 5 ng/mL
Is thermogenic; luteolysis lowers body temp to less than 99 => good way to know if she will be giving birth soon (within 24 hours) is if you take temps regularly
PGF2alpha and Labor
PGFalpha = luteolytic
Luteolysis will cause progesterone to drop to less than 2 ng/mL
What do radiographs at time of labor tell you?
Number of fetuses
Size of fetuses
Position
What is the most reliable method for assessing fetal stress?
Ultrasound
Fetal stress: Low HR (less than 150)
Fetus Heart Rate
180 to 220 bpm
Fetus Heart Rate in Which Death is Imminent
100 bpm
Stage 1 Labor
Signs
Panting Nervous Restless Nesting Vomiting
Stage 1 Labor
Length
6 to 12 hours
Nervous first mothers usually have longer labor
Stage 1 Labor
If too long?
Potentially uterine inertia (not contracting)
Stage 2 Labor
What occurs?
Contraction of uterus
Visible abdominal straining
Green or clear fetal fluid (bright or dark red is abnormal)
Amniotic sac may be visible
Stage 2 Labor
When should first puppy/kitten be delivered?
Within 4 hours
Once fetus is visible it should be delivered within 20 minutes
Stage 2 Labor
When should entire litter be delivered?
Within 12 hours
Stage 3 Labor
What occurs?
How long?
Passing of placenta
Shortening of uterus
Rest period of 1 to 2 hours
Delivery; how long should you wait between puppies
Max 2 hours
If getting close to 2 hours need to intervene
Uterine inertia:
Complete primary inertia (what is it)
Normal birth canal
No fetuses delivered
Uterine dysfunction
What can cause uterine dysfunction?
Small litter and inadequate stimulation Large litter and over distended uterus Systemic disease Electrolyte imbalance Fatty infiltration of uterus Uterine age Unknown
Partial primary inertia
Normal birth canal
Some fetuses born
Uterus becomes fatigued
Secondary inertia
Uterus exhausted due to obstruction to passage of fetus
Obstruction: Narrow pelvic canal Large fetus Abnormal presentation Fetus malformation Vaginal septum or stricture
Uterine inersia
Treatment
Caesarean section surgery required with complete primary inertia (sometimes with primary partial and secondary as well)
Surgery a must with more than 4 fetuses
Medical management:
Successful for about 27% of patients (IV fluids, dextrose, oxytocin) -> if 1-3 puppies remain
Dystocia and Examining Mother
Ultrasound is best; check for fetal stress
Blood tests for PCV, TP, calcium, glucose
Dystocia
Vaginal Examination
Sterile gloves and lubricant!
Check for: Relaxation Contraction Presence of fetus at pelvic inlet Try and extend neonate feet forward
Repositioning Fetus
Rotate along long axis slightly to help pass through pelvic canal
Cautious using instruments to not hurt neonates or uterus
Can lift and rotate mother to help bring fetus into pelvic canal
Stimulate Ferguson Reflex
What is the Ferguson Reflex?
Putting fingers into the pelvic canal stimulating contraction (body thinks its a puppy coming out) while simultaneously causing abdominal contraction
Medications for Dystocia
First steps
Determine if in Stage 1 or Stage 2 uterine inertia/dystocia
Medications for Dystocia
IV fluids to support BP
10% glucose for hypoglycemia
10% Calcium Gluconate for hypocalcemia (1 mL/4.5 kg body weight every 4-6 hours) – monitor HR
Low dose oxytocin following fluids, glucose, and calcium
Medications for Dystocia
Precautions with Oxytocin
Initial dose 0.2 to 0.5 units per mother (canine or feline)
Maximum: 2 units or 3 doses
Wait 20 minutes between administration
Too much will get uterine contraction as a unit opposed to “waves”
Caesarean Section Surgery
Dystocia
Cautions
Required when medical management is not feasible
Post-hemorrhage is concern
Oxytocin may be given to assist uterine involution
Drugs for Caesarean Surgery
Pre-anesthetic oxygen
Glycopyrolate pre-anesthetic (low passing into placenta)
Propofol for induction (minimal effect on fetus)
Isoflurane
Oxytocin to promote uterine involution
Tramadol for pain control
Drugs not to be given:
Preanesthetic (why)
Atropine
Relaxes maternal lower esophageal sphincter; causes regurgitation
Drugs not to be given:
Sedatives (why)
Dexmedetomidine Xylazine Phenothiazine Ketamine Barbiturates
Neonatal and maternal cardio-depressant and overall depressant
Drugs not to be given:
Opioids (why)
Neonatal respiration
If given must be able to be reversed!
Drugs not to be given:
Anti-inflammatory
NSAIDs
Impairs neonatal nephron development and hepatic function
