Complications1-Table 1 Flashcards
1
Q
What causes physiologic anemia?
A
Normal changes in ratio of plasma to RBC volume
2
Q
How is physiologic anemia reflected?
A
As decreased Hct d/t the dilutional effect relative to each trimester
3
Q
What are lab findings associated with Iron def anemia?
A
decreased Hct
4
Q
What finding may accompany iron def anemia?
A
PICA
5
Q
How is iron def anemia tx in preggo people?
A
Add an additional 60-80mg elemental iron daily
6
Q
Why it taking folate a good idea?
A
Reduce the risk of NTD
7
Q
How much dietary folate should be taken in?
A
400-800 mcg or 0.4-0.8mg
8
Q
How much folate is in a prenatal vitamin?
A
1mg, 1000mcg
9
Q
What would indicate a need to increase daily folate to 4mg or 4000mcg daily?
A
- multifetal gestation
- mom on anticonvulsants
- past hx of NTD pregnancy
10
Q
What are hemoglobinopathies?
A
heterogeneous group of single gene disorders that include structural Hb variants
11
Q
What is the Hb variant in sickle cell?
A
Hb A replaced with Hb S
12
Q
What is sickle cell dz?
A
Homozygotes HbSS
Unstable sickled shape to RBC
Increased viscosity and hemolysis
Decreased oxygenation
13
Q
What is sickle cell trait?
A
Heterozygoutes Hb AS
Asymptomatic
14
Q
What is isoimmunization?
A
Formation of maternal antibodies, aka maternal alloimmunization
15
Q
What leads to hemolytic dz of the newborn?
A
Binding of maternal antibodies to fetal RBC antigens
16
Q
What is hemolytic dz of the newborn characterized by?
A
Hemolysis, bili relsease, anemia
17
Q
How is the severity of hemolytic dz of the newborn determined?
A
- how much antibody was produces
- how strongly antibody binds to antigen
- ability of the fetus to replenish the destroyed RBC
18
Q
What are the 4 major blood groups determined by?
A
Presence or absence of A & B RBC surface antigens
19
Q
What makes group A?
A
has A antigen on RBCs & B antibody in plasma
20
Q
What makes group B?
A
has B antigen on RBCs & A antibody in plasma
21
Q
What makes group AB?
A
has both A & B antigens on RBCs but neither A nor B antibody in plasma
22
Q
What makes group O?
A
has neither A nor B antigens on RBCs but both A & B antibodies in plasma
23
Q
What is the 3rd antigen? When is it a problem?
A
Rh (rhesus) factor
Either present + or absent –
Positive is ok, negative is an issue unless both mom and dad are negative
24
Q
What is the Rh system composed of?
A
A complex of 5 antigens
C, c, D, E, e
25
What is the most common antigen? Hint its part of the Rh- CDE system
Antigen D
26
What is the deal with antigen D?
Present: Rh-D positive
Absent: Rh-D negative
27
Why is antigen D important?
There is isoimmunization potential when an Rh-D negative woman is preggo with a fetus that is positive!
28
How much Rh-D blood is sufficient to cause isoimmunization?
29
How does this work?
Maternal antibodies pass to baby via placenta and cause an antibody response that destroys fetal RBC
30
Is isoimmunization with Rh a concern with 1st pregnant?
Not really- first pregnancy is exposure to mom and second is when the fetus is typically attacked
Gets progressively worse with each subsequent pregnancy
31
What are some events that might precipitate maternal exposure to fetal RBC?
—1st trimester bleeding: abortion, ectopic
—Placental abruption or previa( placenta is in front of the fetus)
—Childbirth, delivery of placenta
—Procedures: amniocentesis, external cephalic version
—Trauma (fetomaternal hemorrhage), parvo, CMV, toxo, syphilis
The most common cause of events is Rh and Parvo
32
What needs to be screened for for Parvo virus?
IgM & IgG specific antibodies B19
33
What indicates an acute infection and need to evaluate the fetus?
IgM
34
What does parvo virus do?
inhibits erythropoiesis d/t preference for erythroid progenitor cells
35
When is the greatest fetal risk?
36
How is parvo assessed and diagnosed in the fetus?
Doppler MCA- to look at flow of blood through MCA
US- to r/o hydrops
Amniotic fluid- look for fetal blood B19 DNA
37
What finding of Doppler of MCA would indicate no fetal anemia?
measure blood viscosity based on peak velocity of systolic flow (PSV) … less viscous with increased flow in no anemia… more viscous and slower flow indicated anemia
38
When is the peak incidence for hydrops?
4-6wks following maternal infection
39
How often should you do US/ MCA Doppler?
Weekly through 12 weeks post infection
40
When maternal antibodies enter and bind to fetal RBC, there is significant hemolysis and release of bilirubin. What can markedly elevated bili levels lead to?
Kernicterus- leads to permanent neuro symptoms and death
41
Why does anemia occur with hemolysis?
Fetus cannot produce enough RBC to replenish the lysed RBC
42
What is significant fetal anemia?
increased fetal hematopoiesis w/recruitment of alternate sites for RBC production
43
What happens with the fetal liver in significant fetal anemia?
Decreased oncotic pressure can lead to ascites, SQ edema, or pleural effusions
High output cardiac failure and myocardial ischemia
44
What can severe anemia result in?
Hydrops fetalis
45
What are the 2 types of hydrops fetalis?
Immune
| Non-immune
46
What is immune hydrops?
complication of severe Rh incompatibility that results massive red blood cell destruction
47
What is non-immune hydrops?
NIHF) caused by disease or medical condition (cardiac anomaly) that disrupts body's ability to manage fluid
48
What would you expect to see on an US with fetal echo in hydrops?
—Anomalies: fetus, umbilical cord, placenta (thickening)
—Amniotic fluid volume
—Pericardial & pleural effusions, ascites
49
How are the antibodies reported? ( maternal)
They are reported as antibody titer… 1:4, 1:16, etc
50
What is the significance of the titer?
The higher the titer, the more significant antibody response
51
What titer is associated with significant risk for fetal hemolytic dz or hydrops?
Critical titer- 1:8- 1:32
52
What does US with fetal echo asses?
fluid volume, anomalies and hydropic changes
53
What is included in an amniotic fluid assessment?
Bili levels, genetics, ID studies
54
what should happen is an intrauterine fetal transfusion if planned?
Percutaneous umbilical blood sampling…PUBS
55
What is the fetal Hct cutoff for transfusion in a highrisk perinatal center?
30%
56
What can you do to try to prevent isoimmunization?
Anti-D immune globulin to all Rh-D negative women routinely at 28weeks GA AND within 72 hours of delivery or in any circumstance where fetal and maternal blood may come in contact
57
What does anit-D immune globulin do?
Effectively presents sensitization to the D antigen
58
What does the kleihauer- Betke test do?
ID fetal erythrocytes in maternal circulation
| ID appropriate dose of Rh immunoglobulin to be administered
59
What does an indirect Coombs determine?
If the pt has received sufficient antibody
| Positive result = inadequate dosing
60
What is the most important cause of hemolytic dz of the fetus NOT associated with D antigen?
Kell antigens (K,k)
61
What results in Kell antigens?
Usually from a prior blood transfusion
62
What is the result of kell antigens?
Unique anemia…. results from destruction & suppression of hematopoietic precursor cells but hemolysis is limited
63
What is ABO hemolytic dz?
Maternal fetal incompatibility associated with mild fetal anemia and newborn hyperbilirubinemia
64
What is the chorion?
extraembryonic mesoderm on the inner surface creates by the proliferating trophoblast
65
When does the amnion develop?
When cells at the dorsal surface of the embryonic disk form a transparent membranous sac (sac will fill with the amniotic fluid!)
66
What are risks associated with multifetal gestation?
Preterm L&D, IUGR, hydramnios, preeclampsia, placental abruption, PP hemorrhage
67
What has increased the rate of twins?
ART/ovulatory induction
68
What is dizygotic twin gestation?
Fraternal- 2 separate ova fertilized by 2 separate sperm
69
What is monozygotic twin gestation?
Identical: division of fertilized ovum following conception
70
What are the 4 forms of monozygotic twin gestation?
1) Diamnionic/Dichorionic: each fetus is surrounded by an amnion & a chorion w/1 or 2 placentas
- -Division w/in 3 days fertilization
2) Diamnionic/Monochorionic: each fetus will be surrounded by an amnion but will have a single chorion
- -Division w/in 4-8 days fertilization
3) Monoamnionic/Monochorionic: twins will share a common sac as amnion & chorion have already developed
- -Division w/in 9-12 days fertilization
4) Conjoined twins: incomplete division
71
What are the risks associated with monochorionic gesation?
Twin-twin transfusion syndrome
| Chord entanglement and fetal death
72
What is twin- twin transfusion syndrome?
arterial-venous anastomoses may form between fetuses & result in blood flow from one twin to the other
73
What happens to the different fetus in twin-twin syndrome?
1) Donor twin: may have impaired growth, anemia, hypovolemia: have ↓ urine output → oligohydramnios
2) recipient twin: HTN, polycythemia, HF, hypervolemic: have ↑ urine output → hydramnios
74
How can twin- twin transfusion syndrome be tx?
Laser ablation of anastomoses
75
How is cord entanglement tx?
hospitalize @ 26-28 wks & steroid administration
76
When is twin gestation suspected? How is it confirmed?
When uterine size > GA
| US: confirm twin and chorion status
77
When should serial US begin to monitor for discordant growth?
q3-4 wks begin @ 16-18 wks GA
78
When do multifetal gestations tend to deliver?
Preterm
Twin: 35 wk
Triplets: 32 wks
Quads: 30 wks
79
When can twins be delivered vaginally?
Both are in the cephalic position
80
When do twins need to be delivered via c-section?
Both breech presentation
1st twin vertex and 2nd twin isn’t
1st twin is breeched
81
What complications are associated with multifetal deliveries?
Higher risk of cord prolapse, postpartum atony, and hemorrhage
82
What defines SGA?
Infant whose birth weight is
83
What defines IUGR?
Fetus whose weight
84
Why are IUGR associated with higher risk?
Lack adequate reserves to survive in utero, deal w/stress of labor, adapt to neonatal life
85
What is the pathology behind early onset IUGR?
commonly associated w/hereditary factors, immunologic issues, chronic maternal disease, fetal infection, multiple pregnancies
86
What is the pathology late early onset IUGR?
primarily related to decreased placental function & nutrient transport = uteroplacental insufficiency
87
What meds that mom takes can affect IUGR?
anticonvulsants, warfarin, folic acid antagonists
88
What viral infection in mom can cause IUGR?
CMV, rubella, varicella
89
What placental factors can lead to IUGR?
Defective trophoblastic invasion of placenta
Uterine abnormalities: limit placental growth & development,
Genetic composition of placenta
90
How is IUGR diagnosed?
FH-serial measurements, US, direct invasive studies
91
What is FH looking for to diagnose IUGR?
20 - 36 weeks EGA: height should increase approx 1 cm/week
| discrepancy >2cm may indicate IUGR
92
What is the US examining?
Fetal biometric parameters (provide estimated growth rate of fetus)
- biparietal diameter (BPD)
- head circumference (HC)
- abdominal circumference (AC)
- femur length
93
What direct invasive studies are used to look for IUGR?
Amniocentesis
Doppler velocimetry
Doppler MCA flow
94
What does Doppler velocimetry asses? What is normal?
Fetal-placental circulation in umbilical artery - measure systolic/diastolic (S/D) ratio
—Normal ratio @ term = 1.8 to 2.0
95
What is the management goal of IUGR fetus?
Deliver the healthiest possible infant and the optimal time
96
What should staff be prepped for when delivering a fetus with IUGR?
hypoglycemia, RDS, hypothermia, hyperviscosity syndrome
97
What is hyperviscosity syndrome?
d/t fetus’s attempt to compensate for poor placental oxygen transfer by increasing Hct > 65% marked polycythemia s/p birth
98
What can hyperviscosity syndrome lead to?
multiorgan thrombosis, HF, hyperbilirubinemia
99
What is LGA?
Infant whose birth weight > 90% for GA based on population specifics
100
What is macrosomia?
Fetus weighing > 4,500 grams (9 lbs = 4,800 grams or 4.8 kg)
101
What maternal factors contribute to macrosomia?
```
Prior hx macrosomia
Maternal prepregnancy weight, wt gain during pregnancy
Multiparity
GA > 40 weeks
Ethnicity
Maternal birth weight/height
Maternal age
```
102
What risks are associated wit macrosomia for the fetus?
Shoulder dystocia, brachial plexus injury, fx clavicle
| If mom obese or DM: hypoglycemia, prematurity, stillbirth, hypothermia
103
What risks are associated wit macrosomia for mom?
- Cesarean delivery
- Postpartum atony/hemorrhage
- Vaginal lacerations
104
How is macrosomia diagnosed?
Clinical estimation of fetal weight
- serial FH and Leopold
US
- fetal biometric parameters
105
What other conditions should you have on your DDX when dealing with macrosomia?
—Multifetal gestation
—Polyhydramnios
—Large placenta: molar IUP
—Large uterus: fibroids
106
How is macrosomia managed?
Non- GDM: no intervention, balance C section vs vaginal for safety
GDM: strict control of blood glucose and elective c section if EFW>4500
107
When is amniotic fluid produced?
Continuously after 16 wks
108
What is the role of amniotic fluid?
Protects against infection, trauma, umbilical cord compression, allows fetal mvmt and breathing
109
What is PROM? What is PPROM?
premature rupture of membranes before onset of labor; >37 weeks and is followed often by labor
Preterm PROM : occurs
110
What is the leading cause of neonate mobidity and mortality?
PPROM
111
When is it a PPROM previable subset?
20-25.6 weeks
112
What can cause P/PP ROM?
STDs around 32 weeks, subclinical infection
113
What are risk factors?
Prior PROM, short cervical length, prior preterm delivery, multifetal gestation, threatened AB, polyhydramnios, smokers
114
What are major risks for P/PP ROM?
intrauterine infection (chorioamnionitis), prolapsed cord, placental abruption
115
What is Chorioamnionitis?
Infection of membranes & amniotic fluid fever
| Risk of sepsis leading to CP and CAN abnormalities in baby
116
What is the clinical presentation of Chorioamnionitis?
fever > 100.5F, maternal & fetal tachycardia, uterine tenderness, spontaneous/dysfunctional labor
mom describes gush of fluid or a steady leak
late sign: purulent cervical discharge
117
How is Chorioamnionitis diagnosed?
Clinically- labs are non-specific
| Vaginal fluid = amniotic fluid until proven otherwise!!!
118
What test will rile in amniotic fluid?
—Nitrazine test: uses pH to distinguish amniotic fluid from urine or vaginal secretions
•Amniotic fluid: alkaline w/pH > 7.1, vaginal secretions: pH 4.5-6.0; urine: pH
119
What should you look for on US in choriamnionitis?
Large pockets vs very little fluid
120
How is Chorioamnionitis tx?
IV antibiotics, deliver promptly
121
How is term PROM managed?
Induction with oxytocin or expectant management… most will go into labor within 24hrs
122
When can you do expectant management for PROM?
If there are no other risk factors, just make sure to do serial eval for IU infections
123
What is done regardless of management for PROM?
GBS prophylaxis
124
What is the latency period?
Time from PROM to labor and is inversely related to GA
125
How is PPROM managed?
34 wks: deliver
32-33: steroid for lung maturation
24-31: admit mom, abx, steroid for lungs, daily fetal assessment by US with CBC.WBC, try to manage expectantly until complete 33 weeks
126
What are common causes of third trimester bleeding?
Intercourse, vaginitis, recent pelvic exam (cervix highly vascular & friable)
127
What are the 2 most common causes?
Placenta previa
| Placental abruption
128
Third trimester bleeding is considered what?
A true OB EMERGENCY
129
How is third trimester bleeding managed?
- Admit
- Establish IV access
- Labs: CBC, coagulation panel, blood type & screen (cross match 4 units), Rh status, Kleihauer-Betke test
- US: placental location
- Electronic monitoring of fetal heart
130
When does placenta previa occur?
When the placenta partially or completely covers the cervical oz
131
What are the forms of previa?
—Complete: total coverage of internal cervical os
-Rarely resolves spontaneously
—Partial: overlies part of internal cervical os
—Low-lying: extends into lower uterine segment but does not reach internal cervical os
132
Which form of previa usually resolves?
Low-lying partial
133
What are risk factors for placenta previa?
advanced age, smoking, cocaine use, multiparity, previous history of previa
134
What will be the typical pt presentation with previa?
Painless vaginal bleeding
135
How is previa diagnosed?
US
136
How is previa managed?
—1st episode usually cease in 1 - 2 hours
—Patient will be observed closely
-Either admit to Maternal Special Care Unit or compliant patients (stable condition, live close to hospital, have someone w/them at all times) can be monitored as an outpatient
—Patient delivered by C-section between 36 - 38 weeks
-s/p amniocentesis: fetal lung maturity
137
What are complications of previa?
—Hemorrhage
| —Placenta may be abnormally adherent to uterine wall
138
What are the placenta to wall abnormalities?
- Placenta accrete: placental tissue extends into superficial layer of myometrium
- Placenta increta: extends further into myometrium
- Placenta percreta: extends completely through myometrium to serosa & sometimes adjacent organs
139
What is placental abruption?
Abruptio placentae…. Abnormal premature separation of normally implanted placenta after 20th week of gestation but before birth
140
What are the types of abruption?
—Complete: entire placenta separates
—Partial: only portion separates
---Marginal: limited to edge of placenta
141
What is the cause of abruption?
bleeding in decidua basalis causes separation of the placenta ---- concealed hemorrhage
142
What are risk factors for abruption?
Trauma, previous hx of abruption, chronic HTN, preeclampsia, multifetal gestation, advanced maternal age, multiparity, smoking, cocaine, chorioamnionitis
143
What are the clinical features of abruption?
Hx: painful vaginal bleeding: uterine, abdominal or back pain
PE: tender uterus on palpation
144
How is abruption diagnosed?
US
145
How is abruption managed?
Monitor: VS, IV fluids, deliver w/severe hemorrhage
| --C-section: most common but vaginal delivery possible especially w/rapid labor
146
What are complications of abruption?
Couvelaire uterus
| Coagulopathy: DIC
147
What is couvelaire uterus?
blood will penetrate uterus causing serosa to appear blue or purple
148
How is couvelaire uterus diagnosed?
Kleihauer-Betke test… determine amount of Rh-D needed and need for transfusion
149
What should you look at to confirm DIC?
PT/INR & aPTT – both prolonged; platelet count low
150
What is vasa previa?
Passage of fetal blood vessels over internal os below presenting part of fetus
151
Where can vasa previa occur?
Velamentous insertion: fetal blood vessels insert into membranes between amnion & chorion instead of the placenta & not protected by Wharton jelly
Succenturiate lobe: lobe of the placenta separates from the main placenta
152
What is a uterine rupture?
Spontaneous complete transection of uterus from endometrium to serosa
153
What are the types of uterine rupture?
```
Partial rupture (uterine dehiscence) when peritoneum remains intact
Complete rupture: fetal expulsion into abdomen w/ fetal mortality 50 -75%
```
154
Where do most uterine ruptures occur?
Site of previous C section
155
What are risk factors for uterine rupture?
vaginal birth after cesarean (VBAC)
156
What determines survivability?
whether large portion of placenta remains attached and how fast operative delivery is accomplished
157
What causes physiologic anemia?
Normal changes in ratio of plasma to RBC volume
158
How is physiologic anemia reflected?
As decreased Hct d/t the dilutional effect relative to each trimester
159
What are lab findings associated with Iron def anemia?
decreased Hct
160
What finding may accompany iron def anemia?
PICA
161
How is iron def anemia tx in preggo people?
Add an additional 60-80mg elemental iron daily
162
Why it taking folate a good idea?
Reduce the risk of NTD
163
How much dietary folate should be taken in?
400-800 mcg or 0.4-0.8mg
164
How much folate is in a prenatal vitamin?
1mg, 1000mcg
165
What would indicate a need to increase daily folate to 4mg or 4000mcg daily?
- multifetal gestation
- mom on anticonvulsants
- past hx of NTD pregnancy
166
What are hemoglobinopathies?
heterogeneous group of single gene disorders that include structural Hb variants
167
What is the Hb variant in sickle cell?
Hb A replaced with Hb S
168
What is sickle cell dz?
Homozygotes HbSS
Unstable sickled shape to RBC
Increased viscosity and hemolysis
Decreased oxygenation
169
What is sickle cell trait?
Heterozygoutes Hb AS
| Asymptomatic
170
What is isoimmunization?
Formation of maternal antibodies, aka maternal alloimmunization
171
What leads to hemolytic dz of the newborn?
Binding of maternal antibodies to fetal RBC antigens
172
What is hemolytic dz of the newborn characterized by?
Hemolysis, bili relsease, anemia
173
How is the severity of hemolytic dz of the newborn determined?
- how much antibody was produces
- how strongly antibody binds to antigen
- ability of the fetus to replenish the destroyed RBC
174
What are the 4 major blood groups determined by?
Presence or absence of A & B RBC surface antigens
175
What makes group A?
has A antigen on RBCs & B antibody in plasma
176
What makes group B?
has B antigen on RBCs & A antibody in plasma
177
What makes group AB?
has both A & B antigens on RBCs but neither A nor B antibody in plasma
178
What makes group O?
has neither A nor B antigens on RBCs but both A & B antibodies in plasma
179
What is the 3rd antigen? When is it a problem?
Rh (rhesus) factor
Either present + or absent –
Positive is ok, negative is an issue unless both mom and dad are negative
180
What is the Rh system composed of?
A complex of 5 antigens
| C, c, D, E, e
181
What is the most common antigen? Hint its part of the Rh- CDE system
Antigen D
182
What is the deal with antigen D?
Present: Rh-D positive
Absent: Rh-D negative
183
Why is antigen D important?
There is isoimmunization potential when an Rh-D negative woman is preggo with a fetus that is positive!
184
How much Rh-D blood is sufficient to cause isoimmunization?
185
How does this work?
Maternal antibodies pass to baby via placenta and cause an antibody response that destroys fetal RBC
186
Is isoimmunization with Rh a concern with 1st pregnant?
Not really- first pregnancy is exposure to mom and second is when the fetus is typically attacked
Gets progressively worse with each subsequent pregnancy
187
What are some events that might precipitate maternal exposure to fetal RBC?
—1st trimester bleeding: abortion, ectopic
—Placental abruption or previa( placenta is in front of the fetus)
—Childbirth, delivery of placenta
—Procedures: amniocentesis, external cephalic version
—Trauma (fetomaternal hemorrhage), parvo, CMV, toxo, syphilis
The most common cause of events is Rh and Parvo
188
What needs to be screened for for Parvo virus?
IgM & IgG specific antibodies B19
189
What indicates an acute infection and need to evaluate the fetus?
IgM
190
What does parvo virus do?
inhibits erythropoiesis d/t preference for erythroid progenitor cells
191
When is the greatest fetal risk?
192
How is parvo assessed and diagnosed in the fetus?
Doppler MCA- to look at flow of blood through MCA
US- to r/o hydrops
Amniotic fluid- look for fetal blood B19 DNA
193
What finding of Doppler of MCA would indicate no fetal anemia?
measure blood viscosity based on peak velocity of systolic flow (PSV) … less viscous with increased flow in no anemia… more viscous and slower flow indicated anemia
194
When is the peak incidence for hydrops?
4-6wks following maternal infection
195
How often should you do US/ MCA Doppler?
Weekly through 12 weeks post infection
196
When maternal antibodies enter and bind to fetal RBC, there is significant hemolysis and release of bilirubin. What can markedly elevated bili levels lead to?
Kernicterus- leads to permanent neuro symptoms and death
197
Why does anemia occur with hemolysis?
Fetus cannot produce enough RBC to replenish the lysed RBC
198
What is significant fetal anemia?
increased fetal hematopoiesis w/recruitment of alternate sites for RBC production
199
What happens with the fetal liver in significant fetal anemia?
Decreased oncotic pressure can lead to ascites, SQ edema, or pleural effusions
High output cardiac failure and myocardial ischemia
200
What can severe anemia result in?
Hydrops fetalis
201
What are the 2 types of hydrops fetalis?
Immune
| Non-immune
202
What is immune hydrops?
complication of severe Rh incompatibility that results massive red blood cell destruction
203
What is non-immune hydrops?
NIHF) caused by disease or medical condition (cardiac anomaly) that disrupts body's ability to manage fluid
204
What would you expect to see on an US with fetal echo in hydrops?
—Anomalies: fetus, umbilical cord, placenta (thickening)
—Amniotic fluid volume
—Pericardial & pleural effusions, ascites
205
How are the antibodies reported? ( maternal)
They are reported as antibody titer… 1:4, 1:16, etc
206
What is the significance of the titer?
The higher the titer, the more significant antibody response
207
What titer is associated with significant risk for fetal hemolytic dz or hydrops?
Critical titer- 1:8- 1:32
208
What does US with fetal echo asses?
fluid volume, anomalies and hydropic changes
209
What is included in an amniotic fluid assessment?
Bili levels, genetics, ID studies
210
what should happen is an intrauterine fetal transfusion if planned?
Percutaneous umbilical blood sampling…PUBS
211
What is the fetal Hct cutoff for transfusion in a highrisk perinatal center?
30%
212
What can you do to try to prevent isoimmunization?
Anti-D immune globulin to all Rh-D negative women routinely at 28weeks GA AND within 72 hours of delivery or in any circumstance where fetal and maternal blood may come in contact
213
What does anit-D immune globulin do?
Effectively presents sensitization to the D antigen
214
What does the kleihauer- Betke test do?
ID fetal erythrocytes in maternal circulation
| ID appropriate dose of Rh immunoglobulin to be administered
215
What does an indirect Coombs determine?
If the pt has received sufficient antibody
| Positive result = inadequate dosing
216
What is the most important cause of hemolytic dz of the fetus NOT associated with D antigen?
Kell antigens (K,k)
217
What results in Kell antigens?
Usually from a prior blood transfusion
218
What is the result of kell antigens?
Unique anemia…. results from destruction & suppression of hematopoietic precursor cells but hemolysis is limited
219
What is ABO hemolytic dz?
Maternal fetal incompatibility associated with mild fetal anemia and newborn hyperbilirubinemia
220
What is the chorion?
extraembryonic mesoderm on the inner surface creates by the proliferating trophoblast
221
When does the amnion develop?
When cells at the dorsal surface of the embryonic disk form a transparent membranous sac (sac will fill with the amniotic fluid!)
222
What are risks associated with multifetal gestation?
Preterm L&D, IUGR, hydramnios, preeclampsia, placental abruption, PP hemorrhage
223
What has increased the rate of twins?
ART/ovulatory induction
224
What is dizygotic twin gestation?
Fraternal- 2 separate ova fertilized by 2 separate sperm
225
What is monozygotic twin gestation?
Identical: division of fertilized ovum following conception
226
What are the 4 forms of monozygotic twin gestation?
1) Diamnionic/Dichorionic: each fetus is surrounded by an amnion & a chorion w/1 or 2 placentas
- -Division w/in 3 days fertilization
2) Diamnionic/Monochorionic: each fetus will be surrounded by an amnion but will have a single chorion
- -Division w/in 4-8 days fertilization
3) Monoamnionic/Monochorionic: twins will share a common sac as amnion & chorion have already developed
- -Division w/in 9-12 days fertilization
4) Conjoined twins: incomplete division
227
What are the risks associated with monochorionic gesation?
Twin-twin transfusion syndrome
| Chord entanglement and fetal death
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What is twin- twin transfusion syndrome?
arterial-venous anastomoses may form between fetuses & result in blood flow from one twin to the other
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What happens to the different fetus in twin-twin syndrome?
1) Donor twin: may have impaired growth, anemia, hypovolemia: have ↓ urine output → oligohydramnios
2) recipient twin: HTN, polycythemia, HF, hypervolemic: have ↑ urine output → hydramnios
230
How can twin- twin transfusion syndrome be tx?
Laser ablation of anastomoses
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How is cord entanglement tx?
hospitalize @ 26-28 wks & steroid administration
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When is twin gestation suspected? How is it confirmed?
When uterine size > GA
| US: confirm twin and chorion status
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When should serial US begin to monitor for discordant growth?
q3-4 wks begin @ 16-18 wks GA
234
When do multifetal gestations tend to deliver?
Preterm
Twin: 35 wk
Triplets: 32 wks
Quads: 30 wks
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When can twins be delivered vaginally?
Both are in the cephalic position
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When do twins need to be delivered via c-section?
Both breech presentation
1st twin vertex and 2nd twin isn’t
1st twin is breeched
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What complications are associated with multifetal deliveries?
Higher risk of cord prolapse, postpartum atony, and hemorrhage
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What defines SGA?
Infant whose birth weight is
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What defines IUGR?
Fetus whose weight
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Why are IUGR associated with higher risk?
Lack adequate reserves to survive in utero, deal w/stress of labor, adapt to neonatal life
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What is the pathology behind early onset IUGR?
commonly associated w/hereditary factors, immunologic issues, chronic maternal disease, fetal infection, multiple pregnancies
242
What is the pathology late early onset IUGR?
primarily related to decreased placental function & nutrient transport = uteroplacental insufficiency
243
What meds that mom takes can affect IUGR?
anticonvulsants, warfarin, folic acid antagonists
244
What viral infection in mom can cause IUGR?
CMV, rubella, varicella
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What placental factors can lead to IUGR?
Defective trophoblastic invasion of placenta
Uterine abnormalities: limit placental growth & development,
Genetic composition of placenta
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How is IUGR diagnosed?
FH-serial measurements, US, direct invasive studies
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What is FH looking for to diagnose IUGR?
20 - 36 weeks EGA: height should increase approx 1 cm/week
| discrepancy >2cm may indicate IUGR
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What is the US examining?
Fetal biometric parameters (provide estimated growth rate of fetus)
- biparietal diameter (BPD)
- head circumference (HC)
- abdominal circumference (AC)
- femur length
249
What direct invasive studies are used to look for IUGR?
Amniocentesis
Doppler velocimetry
Doppler MCA flow
250
What does Doppler velocimetry asses? What is normal?
Fetal-placental circulation in umbilical artery - measure systolic/diastolic (S/D) ratio
—Normal ratio @ term = 1.8 to 2.0
251
What is the management goal of IUGR fetus?
Deliver the healthiest possible infant and the optimal time
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What should staff be prepped for when delivering a fetus with IUGR?
hypoglycemia, RDS, hypothermia, hyperviscosity syndrome
253
What is hyperviscosity syndrome?
d/t fetus’s attempt to compensate for poor placental oxygen transfer by increasing Hct > 65% marked polycythemia s/p birth
254
What can hyperviscosity syndrome lead to?
multiorgan thrombosis, HF, hyperbilirubinemia
255
What is LGA?
Infant whose birth weight > 90% for GA based on population specifics
256
What is macrosomia?
Fetus weighing > 4,500 grams (9 lbs = 4,800 grams or 4.8 kg)
257
What maternal factors contribute to macrosomia?
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Prior hx macrosomia
Maternal prepregnancy weight, wt gain during pregnancy
Multiparity
GA > 40 weeks
Ethnicity
Maternal birth weight/height
Maternal age
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What risks are associated wit macrosomia for the fetus?
Shoulder dystocia, brachial plexus injury, fx clavicle
| If mom obese or DM: hypoglycemia, prematurity, stillbirth, hypothermia
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What risks are associated wit macrosomia for mom?
- Cesarean delivery
- Postpartum atony/hemorrhage
- Vaginal lacerations
260
How is macrosomia diagnosed?
Clinical estimation of fetal weight
- serial FH and Leopold
US
- fetal biometric parameters
261
What other conditions should you have on your DDX when dealing with macrosomia?
—Multifetal gestation
—Polyhydramnios
—Large placenta: molar IUP
—Large uterus: fibroids
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How is macrosomia managed?
Non- GDM: no intervention, balance C section vs vaginal for safety
GDM: strict control of blood glucose and elective c section if EFW>4500
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When is amniotic fluid produced?
Continuously after 16 wks
264
What is the role of amniotic fluid?
Protects against infection, trauma, umbilical cord compression, allows fetal mvmt and breathing
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What is PROM? What is PPROM?
premature rupture of membranes before onset of labor; >37 weeks and is followed often by labor
Preterm PROM : occurs
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What is the leading cause of neonate mobidity and mortality?
PPROM
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When is it a PPROM previable subset?
20-25.6 weeks
268
What can cause P/PP ROM?
STDs around 32 weeks, subclinical infection
269
What are risk factors?
Prior PROM, short cervical length, prior preterm delivery, multifetal gestation, threatened AB, polyhydramnios, smokers
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What are major risks for P/PP ROM?
intrauterine infection (chorioamnionitis), prolapsed cord, placental abruption
271
What is Chorioamnionitis?
Infection of membranes & amniotic fluid fever
| Risk of sepsis leading to CP and CAN abnormalities in baby
272
What is the clinical presentation of Chorioamnionitis?
fever > 100.5F, maternal & fetal tachycardia, uterine tenderness, spontaneous/dysfunctional labor
mom describes gush of fluid or a steady leak
late sign: purulent cervical discharge
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How is Chorioamnionitis diagnosed?
Clinically- labs are non-specific
| Vaginal fluid = amniotic fluid until proven otherwise!!!
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What test will rile in amniotic fluid?
—Nitrazine test: uses pH to distinguish amniotic fluid from urine or vaginal secretions
•Amniotic fluid: alkaline w/pH > 7.1, vaginal secretions: pH 4.5-6.0; urine: pH
275
What should you look for on US in choriamnionitis?
Large pockets vs very little fluid
276
How is Chorioamnionitis tx?
IV antibiotics, deliver promptly
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How is term PROM managed?
Induction with oxytocin or expectant management… most will go into labor within 24hrs
278
When can you do expectant management for PROM?
If there are no other risk factors, just make sure to do serial eval for IU infections
279
What is done regardless of management for PROM?
GBS prophylaxis
280
What is the latency period?
Time from PROM to labor and is inversely related to GA
281
How is PPROM managed?
34 wks: deliver
32-33: steroid for lung maturation
24-31: admit mom, abx, steroid for lungs, daily fetal assessment by US with CBC.WBC, try to manage expectantly until complete 33 weeks
282
What are common causes of third trimester bleeding?
Intercourse, vaginitis, recent pelvic exam (cervix highly vascular & friable)
283
What are the 2 most common causes?
Placenta previa
| Placental abruption
284
Third trimester bleeding is considered what?
A true OB EMERGENCY
285
How is third trimester bleeding managed?
- Admit
- Establish IV access
- Labs: CBC, coagulation panel, blood type & screen (cross match 4 units), Rh status, Kleihauer-Betke test
- US: placental location
- Electronic monitoring of fetal heart
286
When does placenta previa occur?
When the placenta partially or completely covers the cervical oz
287
What are the forms of previa?
—Complete: total coverage of internal cervical os
-Rarely resolves spontaneously
—Partial: overlies part of internal cervical os
—Low-lying: extends into lower uterine segment but does not reach internal cervical os
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Which form of previa usually resolves?
Low-lying partial
289
What are risk factors for placenta previa?
advanced age, smoking, cocaine use, multiparity, previous history of previa
290
What will be the typical pt presentation with previa?
Painless vaginal bleeding
291
How is previa diagnosed?
US
292
How is previa managed?
—1st episode usually cease in 1 - 2 hours
—Patient will be observed closely
-Either admit to Maternal Special Care Unit or compliant patients (stable condition, live close to hospital, have someone w/them at all times) can be monitored as an outpatient
—Patient delivered by C-section between 36 - 38 weeks
-s/p amniocentesis: fetal lung maturity
293
What are complications of previa?
—Hemorrhage
| —Placenta may be abnormally adherent to uterine wall
294
What are the placenta to wall abnormalities?
- Placenta accrete: placental tissue extends into superficial layer of myometrium
- Placenta increta: extends further into myometrium
- Placenta percreta: extends completely through myometrium to serosa & sometimes adjacent organs
295
What is placental abruption?
Abruptio placentae…. Abnormal premature separation of normally implanted placenta after 20th week of gestation but before birth
296
What are the types of abruption?
—Complete: entire placenta separates
—Partial: only portion separates
---Marginal: limited to edge of placenta
297
What is the cause of abruption?
bleeding in decidua basalis causes separation of the placenta ---- concealed hemorrhage
298
What are risk factors for abruption?
Trauma, previous hx of abruption, chronic HTN, preeclampsia, multifetal gestation, advanced maternal age, multiparity, smoking, cocaine, chorioamnionitis
299
What are the clinical features of abruption?
Hx: painful vaginal bleeding: uterine, abdominal or back pain
PE: tender uterus on palpation
300
How is abruption diagnosed?
US
301
How is abruption managed?
Monitor: VS, IV fluids, deliver w/severe hemorrhage
| --C-section: most common but vaginal delivery possible especially w/rapid labor
302
What are complications of abruption?
Couvelaire uterus
| Coagulopathy: DIC
303
What is couvelaire uterus?
blood will penetrate uterus causing serosa to appear blue or purple
304
How is couvelaire uterus diagnosed?
Kleihauer-Betke test… determine amount of Rh-D needed and need for transfusion
305
What should you look at to confirm DIC?
PT/INR & aPTT – both prolonged; platelet count low
306
What is vasa previa?
Passage of fetal blood vessels over internal os below presenting part of fetus
307
Where can vasa previa occur?
Velamentous insertion: fetal blood vessels insert into membranes between amnion & chorion instead of the placenta & not protected by Wharton jelly
Succenturiate lobe: lobe of the placenta separates from the main placenta
308
What is a uterine rupture?
Spontaneous complete transection of uterus from endometrium to serosa
309
What are the types of uterine rupture?
```
Partial rupture (uterine dehiscence) when peritoneum remains intact
Complete rupture: fetal expulsion into abdomen w/ fetal mortality 50 -75%
```
310
Where do most uterine ruptures occur?
Site of previous C section
311
What are risk factors for uterine rupture?
vaginal birth after cesarean (VBAC)
312
What determines survivability?
whether large portion of placenta remains attached and how fast operative delivery is accomplished
