OB/GYN II Flashcards
What are the three developmental stages of teratology
- Resistant period
- Day 0-11
- killed by the insult or survive unaffected
- Maximum susceptibility
- day 11-57
- Lower Susceptibility
- After 57 days
- Growth retardation
- Reduction in organ size
What are the categories of structural defects and what is the associated time period that they occur
- Malformations
- 1st trimester
- morphologic defect of a body part or organ
- Deformation
- abnormal forms, shapes or positions of a body part
- 2nd or 3rd trimester
- Disruptions
- defects from interference with a normally developing organ system
- 2nd or 3rd trimester
What is the effect of ionizing radiation
- Time of effect (susceptible period)
- Dose effect
- Less than 10 rads (no effect)
- 10-25 rads some adverse
- greater than 25 classic fetal effects
What are factors effecting access of a drug or medication to the fetus
- Maternal absorption
- drug metabolism
- protein binding and storage
- molecular size
- electrical charge
- lipid solubility
how much alcohol is needed to cause fetal alcohol syndrome
as little as one oz per day
Dose response: the more drinks the more FAS that will present
What are the two most abused drugs in pregnancy
- Alcohol
- cocaine
What is a good predictor for fetal complications from maternal DM
Hemoglobin A1C
What are two types of malfomations found in the fetus of DM mothers
- Caudal regression syndrom with hypoplasia of the caudal spine and lower extremities
- CHD most commonly VSD
What is cretinism
the result of maternal, fetal, and neonatal thyroid hormone deficiency
usually in iodine poor areas
What is PKU
phenylketonuria
genetic d/o characterizeed by a deficiency of phenylalanine hydroxylase, a liver enzyme that catalyzes the conversion of phenylalanine to tyrosine. the resulting high levels of phenylalanine in maternal serum result in high levels in the fetus.
adverse effects:
- mental retardation
- microcephaly
- CHD
- low birth weight
what is arrhenoblastoma
virilizing tumor
What are the common abnormalities associated with epilepsy
Clift lip
cleft palate
CHD
Valproic Acid caries a 1-2% risk of NTD
Some studies suggest that the frequency of seizures is correlated with the degree of abnormality
What is the #1 cause of death during pregnancy
Thromboembolism
What is the teratogenic effect of benzodiazepines
less than 1% risk of cleft anomalies
What are the effects of fetal warfarin syndrome
- Flattened nasal bridge
- stippled bony epiphyses
- birth weight less than 10th percentil
- ocular defects
- extremity hypoplasia
- developmental retardation
- seizures
- scoliosis
- deafness/hearing loss
- CHD
- death
What is used for the treatment of HIT (heparin induced thrombocytopenia)
Argatroban
Hirudin / bivalirudin
What are the problems with a 1st trimester infection of rubella
- Neuropathologic changes
- microcephaly
- mental and motor retardation
- meninogencephalitis
- Cardiovascular changes
- PDA
- pulmonary artery stenosis
- Atrioventricular septal defects
- ocular defects
- cataracts
- microphthalmia
- retinal changes
- blindness
- inner ear problems
- IUGR
What are the problems associated with an early pregnancy infection of CMV
- Microcephaly and hydrocephaly
- chorioretinits
- hepatosplenomegaly
- cerebral calcification
- mental ratardation
- heart block
- petechiae
What are the associated problems with a 1st trimester infection of HSV-2
- IUGR
- Microcephaly
- Chorioretinits
- cerebral calification
- microphthalmia encephalitis
- miscarriage
What are the associated problems with inutero infection of VZV during the 1st 20 weeks
Several organ systems are effected
- Cutaneous
- Musculoskeletal
- Neurologic
What is the problem with an enterovirus infection such as coxsachie B
Serious or fatal illness (40%) in the fetus
surviving infants may exhibit cardiac malformations; hepatitis, pneumonitis, or pancreatitis or adrenal necrosis
What is substance use
involves taking low, infrequent doses of illicit substances fro experimentation or social reasons. damaging consequences are rare or minor
what is substance abuse
is the persistent or repeated use of a psychoactive substance for more than 1 month, despite the persistence or recurrence of adverse social, occupational, psychological or physical effects
what is substance dependence
WITHDraw IT mneumonic
what is the pharmacologic effect of cocaine
blocks dopamine and norepinephrine reuptake at the postsynaptic junction, thereby increasing CNS irritability
this leads to maternal and fetal vasoconstriction and tachycardia, as well as stimulation of uterine contractions
tocolytic agent of choice: Mag sulfate
Mag Sulfate can also be used to treat seizures
What are the effects of marijuana during pregnancy
no increase in congenital malformations
What are the fetal effects of heroin during pregnancy
no increase in congenital malformations
IUGR
Stillbirth
Prematurity
Increased perinatal death
What are the fetal effects associated with methadone
no increase in congenital abnormalities
associated with low birth weight
What are the fetal effects of tobacco
spontaneous abortion
abruptio placentae
PROM
preterm delivery
lower birth weight
What is placenta previa
implantation of the placenta over the cervical os
What are the three types of placenta previa
- Total placenta previa: placenta completely cover the internal os. Associated with the greatest risk and largest amount of blood loss
- Partial previa: placenta partially covers the os
- marginal previa: the placenta extends to the margin of the internal cervical os
What are the factors thought to cause placenta previa
- Previous placenta previa
- Previous C section
- Multiparity
- Advanced maternal age
- Smoking
- Asian and african descent
- Previous D & C
Placenta previa is associated with painful or painless bleeding
Painless bleeding
70% occurs at rest
Should you do a manual exam to determine placenta previa
NO
unless you are in the OR ready for emergency C section
Confirm placenta previa via ultrasound
What are the complication of PPH (post partum hemorrhage)
- renal damage from prolonged hypotension
- Pituitary necrosis (sheehans syndrome)
- DIC
What is placenta accreta
growth of the placenta into the myometrium or any of its variations due to the asence of decidua basalis
Placenta accreta should always be considered in the presence of placenta previa
What are the 3 types of placenta accreta
- Placenta Accreta: placenta is attached directly to the myometrium
- Placenta Increta: placenta invades the myometrium
- Placenta Percreta: placenta penetrates completely through the myometrium
What is abruptio placentae
premature separation of a normally implanted placenta after 20 weeks gestation.
It is initiated by bleeding into the decidua basalis, the bleeding splits the decidua, and the hematoma that forms causes further splitting. The process may be self limiting
What is the common triad of presenting symptoms associated with placenta previa
vaginal bleeding
uterine or back pain
fetal distress
What necessitates an immediate delivery with a placentae previa
- fetal heart rate tracing is nonreassuring and the gestational age is greater than 24 weeks
- maternal condition deteriorate regardless of gestational age
What is an Apt test
determination of a vasa previa
- blood from the vagina
- adding a small amount of tap water
- centrifuging the sample
- adding the pink supernatant to 1mL of NAOH solution
- Reading the treated sample in 2 minutes
- Pink color: presence of fetal hemoglobin
- Yellow-brown color: presence of adult hemoglobin
How does oxytocin effect labor
Levels of oxytocin increase with labor, but there is not a surge.
The greatest increase is in the number of oxytocin receptors
- Six fold increase in weeks 13-17 gestation
- 80 fold increase at term
- preterm labor has 2-3 times as many receptors than would be expected
How do prostaglandins assist in labor
Labor is associated with an increase in prostaglandins. this is likely the result of inflammation and not labor itself.
However, prostaglandins are believed to be important stimulatros of gap junctions
How is labor characterized
contractions that occur with increasing frequency and intensity, causing dilation of the cervix
What is the role of gap junctions in pregnancy
important cell-cell contacts that facilitate communication between cells via electrical or metabolic coupling
myometrial gap junctions, which are virtually absent during pregnancy increase in size and number before and during labor
Progesterone prevents gap junctions
Estrogen stimulates gap junctions
What are tocolysis agents and what is their functino
pharmacologic inhibition of uterine activity
- Antiprostaglandin agents
- indomethacin
- acetylsalicylic acid
- Calcium channel blockers
- nifedipine
- magnesium sulfate
- B-mimetic agents
- terbutaline
Discuss the stages of labor
- Stage 1
- Entails effacement and dilation. it begins when uterine contractions become sufficiently frquent, intense and long to initiate obvious effacement and dilation of the cervix
- Stage 2
- involves the expulsion of the fetus. it begins with complete dilation of the cervix and ends when the infant is delivered
- Stage 3
- involves the separation and expulsion of the placenta. It begins with the delivery of the infant and ends with the delivery of the placenta
What do contractions do to the uterus
upper segment of the uterus becomes thicker and as labor progresses and contracts down with a force that expels the fetus with each contraction
lower segment of the uterus passively thins out with the contractions of the upper segment, promoting efacement fo the cervix
What is effacement of the cervix
the shortening of the cervical canal from a structure of approximately 2 cm in length to one in which the canal is repalced by a more circlar orifice with almost paper thin edges
effacement occurs as the muscle fibers near tthe internal os are pulled upward into the lower uterine segment
What is the dilation of the cervix
involves the gradual widening of the verival os. must dilate to 10 cm to be considered completley dilated
What are the types of vertex presentations regarding position
Postion is named based on the occiput with in the birth canal (R or L and A or P) in an oblique fashion or
Occiput transverse or
Occiput anterior/posterior
What are the stations of engagement
Station 0 is the level of the ischial spine
Above the ischial spine in cm is the negative station
below the ischial spine in cm is the positive stations
+3 the presenting part is on the perineum
What does it mean if the fetal head is floating
when the fetal head is not engaged at the onset of labor and the fetal head is freely movable above the pelvic inlet
What are the 7 cardinal movements of labor and delivery
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension of the fetal head
- External rotation
- Expulsion
What is engagement
the biparietal diameter of the fetal head, the greatest transverse diameter of the head in occiput presentations, passes through the pelvic inlet
What is associated with an increased risk of infection from ruptured membranes
time
greater than 24 hours regardless if labor has begun
On average how long should the first stage of labor last
12 hours primigravida
7 hours multigravida
What are the 2 phases of the 1st stage of labor
latent
- Prolonged is greater than 20 hours for primi or 14 hours multiparous
active
- prolonged is dlation less than 1.2cm/hour in primi or 1.5 cm/hour in multiparous
On average how long does the second stage of labor last
50 minutes in primigravida
20 minutes in multigravida
still common to last up to 2 hours
What is crowning
encirclement of the largest diameter of the fetal head by the vulvar ring
What are the two types of episiotomy
median
mediolater
episiotomy is easier to repair and heals better than a tear, shortens the second stage of labor, and spares the infants head from prolonged pounding again the perineum
On average how long is the 3rd stage of labor
5 minutes
What are the signs of placental separation
uterus becomes globular and firm
often a sudden gush of blood
umbilical cord protrudes farther out of the vagina
What is the main control of uterine hemostasis
vasoconstricion produced by a well contracted myometrium
May be assisted after the placenta has been delivered by:
Oxytocin
Ergonovine
prostaglandin F2a
Discuss the degrees of lacerations associated with birth
1st degree: invovle the fourchette, perineal skin and vaginal mucosa.
2nd degree: involve the skin, mucosa, fascia and muscles of the perineal body
3rd degree: extend throught the skin, mucosa, and perineal body and involve the anal sphincter
4th degree: are exensions of the third degree tear through the rectal mucosa to expose the lumen of the rectum.
What are the 2 types of fetal heart monitoring
External ultrasound device
Fetal scalp electrode
What is baseline fetal HR
the heart rate that occurs between contractions regardless of accelerations or decelerations
normal FHR is 110-160 and decreases gradually after 16 weeks gestation as the parasympathetic system develops
What are the causes of baseline fetal tachy
FHR greater 160
- hypoxia
- maternal fever
- chorioamnionitis
- prematurity
- drugs
- fetal stimulation
- fetal arrhythmias
- maternal anxiety
- maternal thyrotoxicosis
what are the causes of fetal bradycardia
FHR less than 110
- hypoxia
- drugs
- autonomic mediated reflex
- arrhthmias
- hypothermia
- maternal hypotension
is baseline FHR variability normal
yes
one of the best indicators of intact integration between the fetal CNS and the heart
How is FHR variability characterized
absent: undectable amplitude
minimal: detectable amplitude less than 5 bpm
moderate: amplitude of 6-25
marked: amplitude of more than 25 bpm
what are the two ways to measure contractions and there associated limitations
tocodynamometer: only determines the frequency and NOT intensity or strength
intrauterine pressure catheter (IUPC): measures both frequency and intensity
What define FHR accelerations
before 32 weeks: a peak of at least 10 bpm above baseline lasting 10 seconds or more
after 32 weeks: a peak of at least 15 bpm above baseline between 15 seconds and 2 minutes
what are the 3 types of FHR decelerations
- Early decelerations
- Variable decelerations
- Late decelerations
What determines if a deceleration is prolonged
decreases from baseline of 15 BPM or more and last 2-10 minutes
caused by vagus nerve discharge or fetal hypoxia
define early decelerations
begin with the onset of uterine contractions, reach their lowest point (never below 100 bpm) at the PEAK of contraction and return to baseline as the contraction ends
thought to be caused by local changes in cerebral blood flow which results in stimulation of the vagal centers
these decelerations are physiologic
define variable decelerations
abrupt decreases in fhr with a rapid reurn to baseline (onset of deceleration to nadir less than 30 seconds) that may occur before, during, or after contration
generally are caused by compression of the umbilical cord
What are the types of variable decelerations
mild: duration less than 30 seconds
moderate: Two types
1. Nadir of 70-80 with duration of more than 60 seconds
2. Nadir less than 70 duration 30-60 seconds
severe: nadir less than 70 with duration greater than 60 seconds
define late decelerations
gradual decreases and returns to baseline with uterine contractions (onset to nadir greater than 30 seconds)
the nadir occurs after the peak of contraction
associated mechanisms
- normal variant
- direct myocardial depression
- uteroplacental insufficency
What are some nonreassuring FHR patterns
- repetitive decelerations
- abnormal baseline FHR
- absence of accelerations
- loss of variability
- repetitive late decelerations
What position should the mother avoid to avoid decreased uterine blood flow
supine
in the supine position, the uterus blocks blood flow through the aorta and the inferior vena cava, potentially leading to decreased placental perfusion
placement in a lateral recumbent position during labor causes the uterus to fall away from the great vessels which should improve fetal oxygenation
what is the fetal scalp stimulation test
the examiner rubs the fetal scalp during a digital examination. an acceleration is usually seen in the FHR tracing of the uncompromised, nonacidotic fetus. The presence of an acceleration is associated wiht an intact ANS and a fetal scalp blood pH greater than 7.2
Fetal scalp pH greater than 7.2 isis reassurance that the fetus is not acidotic
what is normal fetal oxygen saturation
between 35 and 75%
if the fetal oxygen sat remains above 30% during labor there appears to be no risk of fetal metabolic acidosis
What is dystocia
abnormal progression of labor. Used an indication for cesarean section
What are the major causes of perinatal morbidity and mortality
low birth weight
congenital abnormalities
What are the indications for a cesarean section
- contraindication to labor
- Dystocia and failed induction of labor
- Emergent conditions that warrant immediate delivery
What are the contraindications to labor
- Placenta previa
- vasa previa
- previous classic cesarean
- previous myomectomy with entrance into uterine cavity
- previous uterine reconstruction
- malpresentations of the fetus
- active genital herpes infection
- previous cesarean section and patient declines trial of labor
What are the types of cesarean sections
- Low transverse (Kerr)
- is made in the noncontractile portion of the uterus
- Lowest potential of blood loss
- Low verical (sellheim or kronig)
- used when more room is needed to remove the fetus
- Classic incision (Sanger)
- Simplest and quickest procedure to perform
- uterine closure is more difficult
What are the types of abdominal incisions used to conduct a cesarean section
- Midline
- Paramedian
- Pfannenstiel: most common, but requires more time to perform
A transperotoneal approach is used almost exclusively today
What are the complications of a cesarean section
- Endomyometritis
- UTI
- Wound infection
- Thromboembolic disorder
- Cesarean hysterectomy
- Uterine rupture in future pregnancy
- Uterine rupture in future pregnancy
What are the 2 types of episiotomy’s
median
mediolateral
What are the indications for an operative vaginal delivery
- Nonreassuring fetal status
- Prolonged second stage of labor
- Certain maternal illness
- Poor voluntary expulsion efforts
What is a prolonged second stage of labor
- Nulliparous: more than 3 hours with regional or 2 hours with out regional
- Multiparous: more than 2 hours with regional or 1 hour without regional
What are the prereqs for instrumental vaginal delivery
- Cervix must be fully dilated
- membranes must be ruptured
- position and station must beknown, and the head must be engaged (0, station)
- maternal pelvis must be judged adequate size for delivery
- bladder should be empty
- skilled operator present
- adequate anesthesia is needed before forceps or vaccum applications
When are classic forceps indicated
primarily for traction when there is to be little or no rotation
What are the classic forceps
- simpson
- elliot
- tucker-McLean
What are the specialized forceps
- Kielland (for rotation)
- Barton (for rotation)
- Piper (for the aftercoming head in breech deliveries)
Name the vaccum extractors
- Mamstrom vacuum extractor
- Plastic cup extractor (more widely used in US)
What is cervical cerclage
A sututre is placed in the cervix to treat cervical incompetence
What are the types of cerclage
- Shirodkar technique
- McDonald Technique: Less trauma and is a simple purse string
- Abdominal Placement: less common but used for short or amputated cervix
When is a cerclage performed
Usually performed between the 12th and 16th week but can be done as late as the 24th week. It is generally removed at the 38th week.
Elective or prophylactic cerclage has a much lower risk of infection compared to waiting until the cervix is dialated
What is a spontaneous abortion
expulsion of the products of conception without medical intervention
what are the types of spontaneous abortion
- Threateed abortion
- Inevitable abortion
- Incomplete abortion
- Missed abortion
- Recurrent pregnancy loss
Discuss a threatened abortion
traditionally used when bleeding occurs in the first half of gestation without cervical dilation or passage of tissue
What is an inevitable abortion
pregnancy loss is diagnosed when bleeding or rupture of membranes occurs with cramping and dilation of the cervix
What is an incomplete abortion
progenancy loss occurs when there has been partial but incomplete expulsion of the products of conception from the uterine cavity
What is a missed abortion
Death of the fetus or embryo may occur without the onset of labor or passage of tissue for a prolonged period
How late can an elective induced abortion be performed
24 weeks in most states
What is a therapeutic abortion
terminations of pregnancy that are performed when maternal risk is associated with continuation of the pregnancy or fetal abnormalities are associated with genetic, chomosomal or structural defects.
What are the techniques used to terminate a pregnancy
- Surgical evacuation:
- Suction curetage (before 12 weeks)
- Dilation and Extraction (after 12 weeks). After 16 weeks forceps are required for extraction
- Induction of labor
What are the medical means for inducing labor
- Prostaglandins
- Urea or hypertonic saline: injected directly into uterine cavity
- Progesterone antagonist: Mifepristone (effectiveness is often increased by administering with prostaglandin E)
How are future pregnancies effected by a suction curetage
incidences of infertility, spontaneous abortion, and ectopic pregnancy do not increase after uncomplicated suction curetage procedures
Normal parturients are less responsive to vasopressors and chronotorpic agents such as ephedrine or phenylephrine. Why is this
decrease in response may be related to down regulation of alpha and beta receptors
How is the uterus effected by blood pressure
As blood pressure decreases so do uterine perfusion
What happens to the diaphragm with a gravid uterus
The diaphragm elevates 4 cm
causes a 20% decrease in FRC
Breathing of complete O2 will denitrogenate the lungs. How will this benefit a patient and how is it effected by during pregnancy.
Nonpregnat patients will be able to tolerate 9 minutes of apnea before oxygen sat drops below 90%. The parturient will only be able to tolerate 2-3 minutes
How does progeesterone effect the GI system
Decrease motility and food absorbtion
For general anesthesia, how is MAC (minimum alveolar concentration) effected during pregnancy
decreased up to 40 %
What is the pain asscoiated with the first stage of labor
distention and stretching associated with the dialation of the cervix
Sensory nerves enter the spinal cord at T10 - L1
What is the pain associated with the second stage of labor
stretching and tearig of fascia, skin, subcutaneous tissue, and other somatic structures
Derived primarily from S2-S4
Discuss the chemical structure of local anesthetics
weak bases that have a 3 part sturcture
- lipophyilic aromatic rin
- intermediate chain
- hydrophilic carbon chain bearing an amino group
The intermediate chain determines which classification a local anesthetic belongs:
- esters have COO
- amides have NHCO
What is the mechanism of local anesthetics
prevent impulse generation in the nerve and propagation by gaining access to the sodium channel abd blocking permeability to sodium ions
What are the common risks associated with epidural
hypotension and postdural headace
may prolong the duration of labor by 30-120 minutes
The hypotension is generally not related to a sympathetic blockade, but a removal of pain
What is the most common epidural combination
Fentanyl (25 micrograms)
sobaric bupivacaine (0.25%, 1mL)
What are some contraindications to epidurals
Clotting disorders
thrombocytopenia
previous spinal surgery
Consider using PCA (IV - patient control anesthesia)
What is used to reverse the effects of opiods
naloxone
When is antenatal test started and what does it include
started twice weekly between 41 and 42 weeks gestation.
It includes:
- Nonstress test (NST)
- Contraction stress test (CST)
- Biophysical profile (BPP)
Discuss the non stress test
a noninvasive test of fetal activity that correlates with fetal well being. FHR accelerations are boserved during fetal movement. An external monitor is used to receorthe FHR, and the mother participates by indicating fetal movements
- Reactive test requires 2 fetal heart rate accelerations of at least 15 beats amplitude of 15 seconds duration in a 20 minute period
- If a test is nonreactive after 40 minutes, a CST is performed
Discuss the contraction stress test
a test of FHR that indirectly measures placental function in response to uterine contractions
An IV infusion of oxytocin is used to stimulate uterine contractions
It is used when the NST is nonreactive
What consists of a negative CST and postive CST
Negative CST:
3 uterine contractions of moderate intensity lasting 40-60 seconds over a 10 minute period with no late decelerations in the FHR tracing
Positive CST:
has late decelerations associated with more than 50% of the uterine contractions.
A CST with inconsistent late decelerations are considered suspect
What is preterm birth
infants born before 37 weeks gestation
before 32 weeks have the greatest risk of poor health outcome and death
75% of preterm births occur after preterm labor and PPROM
What are the risk factors for preterm birth
Sociodemographic
- low socioeconomic class
- African American
- less than 18 or over 40,
- tobacco
- cocaine
- Previous premature birth
Maternal medical and obstetric conditions
- Mullerian malformations
- Cervical insufficiency
- Uterine over distention
- Obstetric conditions: Pre-eclampsia, Placenta Abruptio/previa, IUGR, PROM
Infection
What may be done for women that have a history of preterm birth
administration of progesterone showed to reduce risk of recurrent preterm birth
If a patient presents with vaginal bleeding, what must be done before a digital exam is performed?
ULTRASOUND to rule out placenta previa
What is the benefit of using tocolytics
They will not reduce the rate of preterm birth, however, they will often delay birth for 48 hours and reduce the associated complications
What are tocolytic options currently available
- Magnesium sulfate
- B-mimetics
- Indomethacin
- Nifedipine
What is the mechanism of magnesium sulfate
inhibits uterine contractility.
acts by competitive inhibition of calcium at the motor end plate or the cell membrane, thereby decreasing calcium influx into the cell
What are the complications associated with magnesium sulfate
- Nausea vomiting
- flushing and headache
- muscle weakness
- pulmonary edema
- cardiopulmonary arrest
what are some contraindications to using magnessium sulfate
- renal failure
- myasthenia gravis
- hypocalcemia
What is the only FDA approved B-mimetic used as a tocolytic
Ritodrine
What is the major problem with using indomethacin as a tocolytic
Neonatal side effects is constriction of the ductus arteriosus: Do not use after 32 weeks
Oligohydramnios
pulmonary hypertension
nectrotizing enterocolitis
What is the mechanism of Indomethacin
nonsteroidal anti-inflammatory which inhibits the synthesis of prostaglandins, which are involved in the biochemical process of labor
What is the mechanism of nifedipine
calcium channel blocker decreases smooth muscle contraction
What is the mechanism for ritodrine
smooth muscle relaxation
What are the abolute contraindications to tocolytic therapy
- Severe preeclampsia
- nonreassuring fetal heart rate
- significant antepartum bleed
- clinical chorioamnionitis
What is the leading cause of PPROM
Intramniotic infection
What is used to determine a rupture of membranes
Nitrazine paper turns blue with a pH above 6.0 to 6.5
Amniotic fluid produces a fernlike pattern on a microscope slide when allowed to dry
What is chronic hypertension of pregnancy and what are the associate classifications
Persistent blood pressure greater than 140/90 mmHg before the 20th week of pregnancy
- Mild: over 140/90
- Moderate: 150/100 -170/110
- Severe: over 170/110
Hypertension can be initially diagnosed if it persists longer than 12 weeks postpartum
What is PIH
Pregnancy induced hypertension
- Hypertension onset after 20 weeks gestation
- Absolute MAP of 105
- Absolute BP of 140/90 twice over 6 hours, without prior comparison
- BP returns to normal 12 weeks post partum
What is preeclampsia
Gestataional hypertension with proteinuria
- Proteinuria: 30mg/dL on dipstick or 300 mg on 24 urine
What is HELLP
Variant of severe preeclampsia
- Hemolysis
- elevated liver enzymes
- Low Platelets
What is the effect of the placenta from hypertension
4 - 8 times more likely in pregnancy to develope abruptio placenta
IUGR because of decreased uterine blood flow
Prematurity
Perinatal mortality increase 25%
What are the antihypertensive medications that are used in the treatment during pregnancy
- Hydralazine (reduces afterload but compensates with an increase in HR)
- Alpha methyldopa
- labetalol
- nifedipine
- B-antagonist
What are the pathophysiological changes seen with preeclampsia
- Increased total Peripheral vascular resistance
- Preeclamptic endothelial cells generate less prostacyclin (vasodilator) than normal endothelial cells
- Coagulation system: DIC 10%
- Renal Function: GFR decreased
- Tubular changes: Decreased uric acid clearance is observed prior to a GFR disturbance
- RAAS
What are the clinical manifestations of preeclampsia
Hypertension
edema (related to Na retention)
Hyperreflexia
What is the management of preeclampsia
Delievery is the only known treatment (at 37 weeks is recomended)
With severe preeclampsia before 24 weeks, termination should be offered. Before 32 weeks delivery is a legitimate choice.
What is used for seizure prophylaxis for preeclampsia
Magnesium sulfate
What can be used to reverse Magnesium sulfate toxicity
1 gm calcium gluconate
What are the indications for antihypertensive medications
- Persistent diastolic blood pressure of over 105 mmHg
- Isolated diastolic BP over 110 mmHg
What is the effect of pregnancy on glucose metaolism
increased insulin secretion occurs as a result of B-cell hyperplasia from the increased levels of estrogen and progesterone
Insulin antagonism results from the increase in human somatomammotropin
Does insulin cross the placenta
NOPE
How does fetal glucose relate to maternal glucose
directly proportional
What are the effects of pre existing diabetes on pregancy
Maternal complications
- Preeclampsia
- DKA
- nephropathy
- retinopayth
- infection
- polyhydraminos
- Cesarean delivery
- postpartum hemorrahge
- mortality
Fetal complications
- Miscarriage
- Stillbirth
- Perinatal mortality
- Congenital malformations
What are the congenital malformations associated with a preexisting DM during pregnancy
Anencephaly
spina bifida
VSD
Situs Inversus
Sacral Agenesis (Caudal Regression)
- the risk of congenital abnormalities increases with higher hemoglobin A1C values
What are the glucose goals during pregnancy for preexisting DM
fasting glucose less than 95
2 hour post prandial less than 120
what is a complication of delivering a fetus greater 4000 grams
shoulder dystocia
What is the effect of gestational diabetes on pregnancy
increased risk of macrosomia
increased risk of preeclampsia
increased rate of still birth if fasting glucose is elevated
FETAL ANOMALIES ARE NOT INCREASED
What is the standard for screening for gestational diabetes and what are the parameters
3 hour Glucose tolerance test
- Fasting value: 95 mg/dL
- 1-hour: 180 mg/dL
- 2 hour: 155 mg/dL
- 3 hour: 140 mg/dL
Diagnosis is given if any two of the parameters are met or exceeded
What is the effects of the thyroid during pregnancy
plasma inorganic iodine concentration decreases because of increased renal excretion and increased glomerular filtration
What are the treatment options for hyper thyoidism
PTU (propylthiouracil)
Methimazole
Beta blockers
What is the mechanism of PTU
prevents both the snthesis of thyroid gland and the peripheral conversion of T4 to T3
What is teh mechanism for methimazole
prevents only the release of thyroid hormone and has been associated aplasa cutis (a reversible but developmental disorder of the fetal scalp)
What are the effects of hypothroidism on the fetus during pregnancy
Deceased performance on IQ tests
What are the common bugs for acute urethritis in pregnancy
E Coli
Chlamydia Trachomatis
Neisseria gonorrheae
What is the most common cause of cystitis in pregnancy
E coli 90%
Usually there is NO fever
What is the most common cause of acute pyelonephritis in pregnancy
e coli (90%)
Preisposing factors unique to pregnancy:
- Ureteral compression at the pelvic brim
- decreased tone and peristalsis of the ureters resulting from increased progesterone levels
- Decreased bladder sensitivity
How is anemia define in pregnancy
Hemoglobin concentration less than:
First trimester: 11g/dL
Second trimester: 10.5 g/dL
Third trimester: 11 g/dL
How much additional iron is needed during pregnancy
1000 mg elemental iron
What happens to hematocrit during pregnancy
decreases during the second trimester
What are the pregnancy complications associated with maternal heart disease
Miscarriage
IUGR
Preterm Deliver
Intrauterin demise
Highest risk is associated with pulmonary hypertension, and other conditions with aorta involvement
What treatment options are available during pregnancy against tuberculosis
Isoniazid
Ethambutol
Streptomycin and Rifampin should be avoided in pregnancy
What is the leading cause of death in pregnant and post partum women
thromboembolic disease
What abnormalities increase the risk of thromboembolic disease
Factor V leiden mutation
prothrombin mutation
antiphospholipid antibody
potein c or protein s deficiency
antithrombin III deficiency
homocysteinemia
What causes increased clotting factors during pregnancy
estrogen
venous stasis from a gravid uterus compressing the IVC and pelvic veins also plays a significant role
How is a DVT diagnosed
real time ultrasonography is the procedure of choice
the gold standard is a venography (Invasive and expensive)
What are the findings associated with a PE
tachypnea
dyspnea
pleuritic pain
apprehension
cough
tachycardia
hemoptysis
How is a PE diagnosed
Arterial blood gas less than 80 mmHg
Ventilation Perfusion abnormality
Pulmonary angiogram (gold standard)
Spiral CT tomography
What are the anticoagulants used for thromboembolic disease
heparin or SQ low molecular wight heparin (neither cross the placenta
Warfarin is teratogenic
What are the teratogenic effects of carbamazepine
NTD
Craniofacial defects
nail hypoplasia
What are the teratogenic effects of phenytoin
microcephaly
dysmorphic facies
What are the teratogenic effects of trimethadone
multiple malformations
mental retardation
What are the teratogenic effects of valproic acid
NTD
What is the crierion for developing an Rh isoimmunization
All 3 must be met in an Rh-negative pregnant woman
- Fetus must be Rh positive
- Enough fetal cells must reach the maternal circulation (fetomaternal breech)
- The mother must make antibody to D antigen (as many as 30% are non responders)
How is Rh isoimmunization prevented?
300 micrograms Anti D immunoglobulin (RhoGAM) can protect a mother from up to 30mL of fetal blood
How can assess the degree of hemolysis and risk for fetal death with Rh Isoimmunization pregnancies
Amniocentesis
- Bilirubin in amniotic fluid (byproduct of fetal hemolysis)
- Spectrophotometry: degree of shift at 450nm
- Zone I mild anemia
- Zone II mild to severe anemia
- Zone III severe to death
When should a fetal transfussion be indicated
hematocrit below 30% with Rh isoimmunization pregnancy