Clinical Skills Block 8

why have these previous modalities for predicting the time to onset of parturition in the bitch been not very helpful?

• Radiology

• Ultrasound

• Radiology of late term fetuses provides an estimate of developmental stage but lacks precision in estimating time to parturition

• Ultrasound is of decreasing usefulness for predicting the date of whelping as gestation progresses into the 3rd trimester

what 2 ultrasound findings have shown potential for detecting parturition?

• lung-to-liver ratio of mean grey levels of fetal lung & liver showed potential in identifying the last week of gestation

• fetal GI motility has been suggested to be indicative of fetal maturity

Early research suggested that a transient drop in the _____ temperature of a late pregnant bitch is indicative of impending parturition

rectal

Note: recent research found body temp measured vaginally or rectally was not clinically useful for predicating imminent parturition

conclusions regarding using plasma P4 levels (radioimmunoassay)

• Plasma P4 levels <8.7 nmol/L

• Plasma P4 levels <3.18 nmol/L

• 99% probability of reaching TCD within 48 hours

• 100% probability of reaching TCD within 24 hours

Regression of the CL in the late pregnant bitch is accelerated as the bitch approaches parturition by luteolysis induced by ___

PGF2a

During the period of prepartum luteolysis, low circulating levels of ___ coincide with high circulating levels of ___, a major metabolite of ___

P4, PGFM, PGF2a

Circulating PGFM levels in the bitch start to rise ____ prior to parturition, continue to rise & reach peak values during parturition & decline thereafter

1-2 days

when were bitches admitted in the serum progresterone article?

• 53 days after the first day of cytological diestrus (when that day was known)

• 57 days after last mating

what does cervical dilation mark?

the onset of stage 1 of parturition & indicates that C-section can be performed safely

In the serum progesterone article serum P4 levels were determined using ___

CLIA

In the serum progesterone article serum PGFM levels were analysed using the ____ enzyme immunoassay kit

DetectX

____ is a safe, simple & cost-effective tool that should be a routine procedure in the clinical management of preparturient bitches

vaginoscopy

the study found that absolute PGFM levels are ___ clinically useful, relative PGFM levels __ have clinical utility

not, do

which interferences by serum indices may have contributed to PGFM level variability?

haemolysis, icterus, lipaemia

~5-10% of preparturient bitches will reach TCD within ___ hrs despite a serum P4 level of at least 15.8 nmol/L & 8.7 nmol/L

12

There is a ___% probability that a preparturient bitch will reach TCD within ___ hrs if her serum P4 level is <3.18 nmol/L

95

~90% of bitches that demonstate a ___% increase in PGFM over a 12 hr period are likely to be within __hrs of TCD

20 ; 36

P4 result 2 ng/mL

LH surge

P4 result of 5 ng/mL

ovulation

P4 result of 10 ng/mL

fertilization

The most common proxy for assessing the likely time of the LH surge, ovulation, oocyte maturation & (theoretical) the optimal time for insemination is the ___ associated with the preovulatory leutinization

inital rise in progesterone concentrations

Assays for progesterone do ___ need to be species specific, but they do need to be carefully ___ for that species & the form of the sample (serum or plasma with whatever anticoagulant)

not; validated

T or F? consistency in whatever protocols are followed is likely of more importance in minimizing variability & increasing the reliability of results in the monitoring of individual cycles. The pattern of the increase in concentration values over the course of days is more important than the actual numbers obtained on individual days

T

T or F? results can NOT differ depending on the assay used

F

• what is measured in systemic circulation is typically secreted by the ___ in all mammals, the placenta of some (although not ___) species & in dogs by the stimulated ___ gland

• In the bitch it’s also secreted in significant amounts before ovulation by ___ that are in the process of luteinization induced by the preovulatory surge of LH

• CL; placenta; adrenal

• follicles

Progesterone concentrations exhibit a ___ variation, being significantly ___ in the evening than in the morning in bitches in proestrus & estrus before ovulation but ___ in the morning samples after ovulation

diurnal; higher; higher

____ progesterone concentrations were seen in the ___ than in the ___ samples in pregnant bitches

higher; morning; evening

what measures can be taken to minimize some of the inherent sources of variability?

consistency in sample quality & type, collection timing, processing & analysis & experience in interpreting changes among samples taken during proestrus & estrus

what are the factors involved in dystocia?

• position of offspring in relationship to birth canal of dam

• fetal/maternal spine axis (longitudina vs transverse)

• Uterine inertia (failure of uterus to contract)

  • Primary: contractions never begin

  • Secondary: contractions stop due to fatigue

Stages of Labor

• Stage 1: onset of uterine contractions

• Stage 2: deliver of fetus

• Stage 3: delivery of membranes

Dystocia risk factors

• miniature & small breeds

• Large breeds: small litter size or singleton litters

• Brachycephalic dogs

  • pug, frenchie, English bulldog

Dystocia Hx

• when was the dog bred? Owner observe discharge? Active straining?

• Rectal temperature drop & no onset of labor 24 hours later

• Serum P4 <2ng/ml & 36 hours later & still no onset of labor

• 30 minutes of strong contractions with no delivery of puppy

• more than 2 hours between delivery of puppies

• greater than 4 hours since beginning of stage 2 and no puppy on the ground

Dystocia clinical signs

• female vocalizing

• dam showing signs of pain

• licking at vulva during contractions

• dam unconscious or unresponsive in lateral recumbence

PE dystocia

• presentation of fetal membranes at vulva & no delivery of puppy

• bloody discharge

• greenish-brown discharge

• presence of puppy in vaginal exam upon digital palpation

• vaginal stricture upon digital exam

• Reduced or absent Ferguson Reflex

  • pressure on dorsal aspect vaginal wall stimulates abdominal straining

Diameter of birth canal needs to be at least ___X___ inches to deliver fetal head

1.5, 1.5

On ultrasound, fetal HR ___ bpm or LOWER equals fetal distress

100

Dystocia- should I use oxytocin?

• Be VERY careful

• certainly do NOT use if suspect obstruction

  • can cause placental separation or uterine rupture

• Not of any use if already have strong contractions

when interpreting P4 lab results remember to count from day blood was pulled not day ___ lab results

received

• 9/24: 65-1 day from LH surge

• 9/25: Day 65

• 9/26: Day 65 + 1

• Temp drop on 9/24 means pups on the ground within ___ hours

24

• 7/22 P4 1.4

• 7/25 P4 4.7

• Bred AI on 7/24, 7/26, 7/27

• Decision to cut because __ days from last breeding

• Guideline: minimum ____ days gestation

60

59

How do you evaluate a neonate?

• monitor for daily weight gain!!

• minimum is 5%/day

Equine auscultation

• L hemithorax

  • mitral

  • aortic

  • pulmonary

• R hemithorax

  • tricuspid

• IV-V ICS- dorsal to olecranon (S1)

• IV ICS- below point of the shoulder (cardiac base) (S2), cranial & dorsal to mitral valve

• III ICS- cranio-ventrally the aortic valve (S2)

• III-IV ICS- wide area dorsal to the sternum & just cranial to the mitral valve

Equine lung field limits:

• cranio-dorsal borders

• caudoventral border

• shoulder & epaxial muscles

• line extending from ICS 17th at the level of the tuber coxae, 13th rib at mid thorax, 11th rib at the level of the shoulder to the point of the elbow