Unit 11 - OB Part 2 Flashcards
1
Q
1 major difference in prepping for surgery for a c section under general vs other surgeries
A
prep and drape prior to induction
2
Q
induction drugs to use for C section under GA
A
- 2-2.5 mg/kg propofol
- 0.3 mg/kg etomidate
- 1 mg/kg ketamine
choose 1
3
Q
induction drugs to use for C section under GA
A
- 2-2.5 mg/kg propofol
- 0.3 mg/kg etomidate
- 1 mg/kg ketamine
choose 1
4
Q
should defasiculating dose be given with succs for OB patients
A
not needed – pregnancy reduces risk of myalgia
5
Q
should defasiculating dose be given with succs for OB patients
A
not needed – pregnancy reduces risk of myalgia
6
Q
ideal volatile concentration for c section under GA
A
low concentration of volatile (0.8 MAC) + 50% nitrous oxide
7
Q
risk of neonatal acidosis increases when time between uterine incision and delivery is greater than:
A
3 minutes
8
Q
normal amniotic fluid volume
A
~700 mL
9
Q
fetal risks of nonobstetric surgery during pregnancy
A
- growth restriction
- low birth weight
- demise
- increased incidence of preterm labor
10
Q
ideally, surgery is delayed for how long in pregnant patient?
A
delayed 2-6 weeks after delivery
11
Q
nonobstetric surgeries during pregnancy assoc with highest fetal risks
A
intraabdominal and pelvic surgeries
12
Q
if unable to delay until after delivery, when is the best time for pregnant pt to undergo surgery?
A
2nd trimester
avoids higher risk of teratogenicity in 1st trimester and increased risk of preterm labor in 3rd trimester
13
Q
when is risk of teratogenicity highest
A
during organogenesis (day 13-60)
14
Q
can pregnant patients undergoing nonobstetric surgery have preop anxiolytic
A
yes
Some evidence that links high-dose diazepam in first trimester to cleft palate but Barash says preop benzo is acceptable
15
Q
can pregnant patients undergoing nonobstetric surgery have preop anxiolytic
A
yes
Some evidence that links high-dose diazepam in first trimester to cleft palate but Barash says preop benzo is acceptable
16
Q
at what plasma level does magnesium diminish DTRs
A
5-7 mg/dL
17
Q
is hypokalemia assoc with hyper or hypo-magnesemia
A
hypo
18
Q
how should methergine be admin
A
always IM
IV assoc with severe HTN
19
Q
3 benefits of GA over neuraxial for c section
A
- speed of onset
- secure airway
- greater hemodynamic stability
20
Q
situations that warrant GA for c section
A
- Maternal hemorrhage
- Fetal distress
- Coagulopathy
- Patient refusal of regional anesthesia
- Contraindications to regional anesthesia
21
Q
when are pregnant patients full stomachs
A
18-20 wga
22
Q
aspiration ppx for nonobstetric surgery during pregnancy
A
- sodium citrate 15-30 mL within 15-30 min of induction
- ranitidine 1 hour before induction
- metoclopramide 1 hour before induction
23
Q
at what point in pregnancy should you start LUD
A
2nd & 3rd trimester
24
Q
meds that should be avoided in nonobstetric surgery during pregnancy
A
NSAIDs
potentially close ductus arteriosus
25
meds that should be avoided in nonobstetric surgery during pregnancy
NSAIDs
| potentially close ductus arteriosus
26
why should hyperventilation be avoided in nonobstetric surgery during pregnancy
normal maternal PaCO2 is ~30 mmHg
hyperventilation reduces placental blood flow
27
pregnancy-induced HTN that occurs before 20 weeks gestation
chronic HTN
| does not return to normal after delivery
28
when does gestational HTN develop
after 20 weeks
29
Only away to truly diagnose gestational HTN
after delivery (return to normotensive state rules out chronic HTN)
30
when does preeclampsia develop
after 20 weeks
31
BP in mild preeclampsia
> 140/90
32
BP in severe preeclampsia
> 160/110
33
common UA finding in pt with preeclampsia
proteinuria
34
s/s preeclampsia that may exist in the absence of proteinuria
* persistent RUQ or epigastric pain
* persistent CNS or visual symptoms (HA, hyperreflexia, hyperexcitability, coma)
* fetal growth restriction
* thrombocytopenia
* elevated serum liver enzymes
35
what is eclampsia
mother with preeclampsia develops seizures
36
most common critical pathology associated with the healthy parturient
Preeclampsia
37
preeclampsia is most common in:
mothers < 20 yrs and > 35 yrs
38
moms with highest risk of developing preeclampsia
Patients with chronic renal disease and those that are homozygous for the angiotensinogen T235 allele
39
roles of thromboxane in the pt with preeclampsia
* increased plt aggregation
* increased vasoconstriction
* increased uterine activity
* decreased uteroplacental blood flow
40
roles of prostacyclin in normal pregnancy
* ↓ platelet aggregation
* ↓ vasoconstriction
* ↓uterine activity
* ↑ uteroplacental blood flow
41
roles of thromboxane in normal pregnancy
* ↑ platelet aggregation,
* vasoconstriction
* ↑ uterine activity
* ↓ uteroplacental blood flow
42
prostacyclin and thromboxane production in pt with preeclampsia
produces up to 7x more thromboxane than prostacyclin
43
key maternal complications of preeclampsia
* heart failure
* pulmonary edema
* intracranial hemorrhage
* cerebral edema
* DIC
* proteinuria
44
BP threshold before treating HTN in preeclamptic patient
160/110
45
consequences of endothelial damage resulting from vasoactive substances
* glomerular leak
* activation of clotting cascade
* platelet aggregation
46
proteinuria in mild vs severe preeclampsia
**mild:** < 5 g/24 hr
< 3+ dipstick
**severe** 5+ g/24 hr
> 3+ dipstick
47
what causes proteinuria in preeclamptic patient
Glomerular capillary endothelial destruction
48
24-hr urine total in mild vs severe preeclampsia
mild: > 500 mL
severe: < 500 mL
49
what causes edema in preeclampsia
↓ oncotic pressure
↑ vascular permeability
50
what causes pulmonary edema in severe preeclampsia
Heart failure
↓ oncotic pressure
↑ vascular permeability
51
what causes headache in severe preeclampsia
Cerebral edema
52
what causes visual impairment in severe preeclampsia
Vasoconstriction of ocular arteries
53
what causes epigastric pain in severe preeclampsia
Liver subscapular hemorrhage
Hypoxic liver
54
plt count in mild vs severe preeclampsia
mild = > 100,000
severe = < 100,000
55
does preeclampsia affect fetal growth?
mild - no
severe - yes d/t uteroplacental hypoperfusion
56
primary reasons for medicating a pt with preeclampsia and HTN
to prevent a cerebrovascular accident, myocardial ischemia, and placenta abruption
| medicate when > 160/110
57
primary reasons for medicating a pt with preeclampsia and HTN
to prevent a cerebrovascular accident, myocardial ischemia, and placenta abruption
| medicate when > 160/110
58
treatment for acute HTN in preeclampsia
* **Labetalol** 20 mg IV followed by 40 - 80 mg q 10 min up to a max dose of 220 mg
* **Hydralazine** 5 mg IV q 20 min up to a max dose of 20 mg
* **Nifedipine** 10 mg PO q 20 min up to a max dose of 50 mg
* **Nicardipine** infusion started at 5 mg/hr and titrated by 2.5 mg/hr q 5 min up to a max dose of 15 mg/hr
59
dose of labetolol for HTN assoc with preeclampsia
20 mg IV followed by 40 - 80 mg q 10 min up to a max dose of 220 mg
60
dose of hydralazine for HTN assoc with preeclampsia
5 mg IV q 20 min up to a max dose of 20 mg
61
dosing nifedipine for preeclamptic pt with HTN
10 mg PO q 20 min up to a max dose of 50 mg
62
nicardipine infusion dosing for preeclamptic pt with BP > 160/110
infusion started at 5 mg/hr and titrated by 2.5 mg/hr q 5 min up to a max dose of 15 mg/hr
63
how long do risks of complications with preeclampsia continue
up to 4 weeks postpartum
64
when are the of pulmonary HTN and stroke highest in preeclamptic pt
in postpartum period
65
preeclamptic patients have an exaggerated response to what meds
sympathomimetics
methergine
66
Seizure prophylaxis with magnesium in pt with preeclampsia
4g loading dose over 10 min + infusion 1-2 g/hr
67
antidote for magnesium toxicity
10 mL 10% calcium gluconate IV
68
what is HELLP syndrome
Hemolysis, Elevated liver enzymes, Low Platelet count
69
incidence of HELLP syndrome
Develops in 5-10% of those with preeclampsia
70
definitive treatment of preeclampsia, eclampsia, & HELLP syndrome
delivery of the fetus and placenta
71
HELLP syndrome increases what 2 risks
DIC
intraabdominal bleeding (from liver)
72
s/s HELLP syndrome
epigastric pain
upper abd tenderness
73
how does cocaine use affect MAC
* Acute intoxication increases MAC
* Chronic use decreases MAC
74
reasonable choice of antihypertensive for cocaine user
labetolol
75
reasonable choice of antihypertensive for cocaine user
labetolol
76
hematologic consequence of chronic cocaine use
thrombocytopenia
77
best option to treat hypotension in chronic cocaine user
neo
## Footnote
Hypotension may not respond to ephedrine (d/t catecholamine depletion)
78
best option to treat hypotension in chronic cocaine user
neo
## Footnote
Hypotension may not respond to ephedrine (d/t catecholamine depletion)
79
placenta accreta
placenta attaches to surface of myometrium
80
placenta increta
placenta invades myometrium
81
placenta percreta
placenta extends beyond uterus
82
placenta previa
placenta partially or completely covers cervical os
83
where does the placenta normally implant
into decidua of endometrium
84
preferred anesthesia method in pts with abnormal placental implantation
Although neuraxial is safe, GA is preferred
85
abnormal placental implantation is closely assoc with what 2 conditions
placenta previa & previous c sections
86
sign of placenta previa
painless vaginal bleeding
87
risk factors for placenta previa
* previous c-sections
* history of multiple births
88
placental abruption
Partial or complete separation of the placenta from the uterine wall before delivery
89
6 risk factors for placental abruption
* PIH
* preeclampsia
* chronic HTN
* cocaine use
* smoking
* excessive alcohol use
90
placental disorder assoc with inc risk amniotic fluid embolism
placental abruption
91
s/s placental abruption
* maternal pain
* vaginal hemorrhage
* fetal hypoxia
92
most significant concerns regarding abnormal placental implantation
* impaired uterine contractility
* potential for tremendous blood loss during labor & delivery
93
most common cause of postpartum hemorrhage
uterine atony
94
4 risk factors for uterine atony
* Multiparity
* Multiple gestations
* Polyhydramnios
* Prolonged oxytocin infusion before surgery
95
other causes of OB bleeding
| besides uterine atony
* Retained placenta/placenta fragments
* Laceration to the cervix or vaginal wall
* Uterine inversion
* Coagulopathy
* Placenta previa
* Placental abruption
* Abnormal placental implanation (acreta, increta, percreta)
96
med used to provide uterine relaxation for extraction of retained placenta
IV nitro
97
method to tamponade postpartum hemorrhage when other methods are ineffective
intrauterine balloon
98
methods to stop postpartum hemorrhage
* uterine massage
* oxytocin
* ergot alkaloids
* manual massage
* intrauterine balloon
99
OB conditions assoc with DIC
* AFE
* placental abruption
* intrauterine fetal demise
100
when is APGAR score assessed
1 and 5 min after delivery
101
Apgar score at 1 min correlates with:
fetal acid-base balance
102
Apgar score at 5 min may be predictive of:
neurologic outcome
103
normal apgar score
8-10
104
apgar score assoc with moderate distress
4-7
105
apgar score assoc with impending demise
0-3
106
5 aspects of apgar score
1. heart rate
2. resp effort
3. muscle tone
4. reflex irritability
5. color
107
Apgar scoring - heart rate
* absent = 0
* 1 = < 100
* 2 = > 100
108
Apgar scoring - resp effort
absent = 0
slow, irregular = 1
normal, crying = 2
109
Apgar scoring - muscle tone
limp = 0
some flexion of extremities = 1
active motion = 2
110
Apgar scoring - reflex irritability
absent = 0
grimace = 1
cough, sneeze, or cry = 2
111
Apgar scoring - color
pale, blue = 0
body pink, extremities blue = 1
completely pink = 2
112
normal neonatal HR
120-160
113
normal neonatal RR
30-60
114
when does neonatal breathing begin
30 seconds after delivery
| normal pattern is established at 90 seconds
115
when does neonatal breathing begin
30 seconds after delivery
| normal pattern is established at 90 seconds
116
neonatal SpO2 after delivery
Immediately after delivery, normal SpO2 is **60%**.
It should rise to 90% after 10 minutes
117
after delivery, the baby's HR < ____ is assoc with significantly decreased CO
100
118
considerations for assisted ventilation of neonate
* Supplemental O2 increases risk of inflammatory response
* if assisted ventilation is required, use room air instead of 100% FiO2
* If bradycardia or inadequate oxygenation persists, use of supplemental O2 must be balanced against this risk
119
best indicator of adequate ventilation in neonate
resolution of bradycardia
120
3 possible routes emergency drugs can be given in newborn without IV access
* umbilical vein
* ETT
* IO
121
during which stage of labor are patients with valve stenosis and pHTN at greatest risk
stage 3 (immediate postpartum)
| CO increases 80%
122
during which stage of labor are patients with valve stenosis and pHTN at greatest risk
stage 3 (immediate postpartum)
| CO increases 80%
123
LA least likely to undergo fetal ion trapping
chloroprocaine
124
LA least likely to undergo fetal ion trapping
chloroprocaine
125
hallmark of placenta previa
painless vaginal bleeding ~32 weeks gestation
126
when should uterine rupture be considered in laboring pt with epidural
new onset abdominal pain
127
how does uterine rupture present
* severe abdominal pain
* may have referred shoulder pain from diaphragm irritation 2/2 intraabdominal blood
128
primary contributor to placental drug transfer
maternal concentration of free drug
129
most likely indicator of intravascular volume depletion in preclamptic patient
high Hct
130
priorities in patients with eclampsia
* airway management/aspiration prevention (#1)
* control HTN
* anti-seizure meds
131
why do pregnant pts require increased neo dose to treat hypotension
down-regulation of alpha receptors
132
what explains pregnant pt's reduced sensitivity to sympathomimetics
beta receptor down regulation
133
minimum FHR monitoring for nonobstetric surgery during pregnancy
**< 23 wga:** minimum pre and postop
**> 23 wga**: pre and postop FHR + pre and postop assessment of contractions
134
initial treatment for retained products of conseption
* uterine exam - nitro provides relaxation
* curettage to extract retained products
135
advantages of epidural volume extension technique for CSE
uses smaller dose of LA
more stable hemodynamic profile
faster recovery
136
following IV drug delivery to parturient, drug enters fetus via:
umbilical vein
## Footnote
most of this travels to fetal liver and is subjected to 1st pass metabolism
137
first priority in treating a term parturient with eclampsia
prevent aspiration/airway management
138
is eclampsia an indication for emergency c section
no
seizure typically < 10 min long and not recurrent
139
**minimum** fetal assessment required during anesthesia for non-obstetric abdominal surgery with a fetus **< 23 weeks**
document FHR pre and post op
140
**minimum** fetal assessment required during anesthesia for non-obstetric abdominal surgery with a fetus **> 23 weeks**
document FHR pre and post op along with pre and postop assessment of uterine contractions
141
primary contributor to placental drug transfer
maternal concentration of free drug
142
how does molecular charge affect placental drug transfer
non-ionized = greater transfer
143
how does plasma protein binding affect placental drug transfer
less binding = greater transfer
## Footnote
a high concentration gradient (driving force) between the mother and the fetus is the most important contributor of placental drug transfer.
144
most common first sign of uterine rupture
fetal bradycardia
145
"classic" triad of s/s with uterine rupture
abdominal pain
vaginal bleeding
abnormal FHR pattern
| only in ~9%
146
s/s uterine rupture
severe abdominal pain
fetal bradycardia
vaginal bleeding
undetectable uterine contractions
breakthrough pain with epidural that was previously working
147
surgical treatment options for uterine rupture
uterine repair
arterial ligation
hysterectomy
## Footnote
The mother may require a c-section
148
surgical treatment options for uterine rupture
uterine repair
arterial ligation
hysterectomy
## Footnote
The mother may require a c-section
149
what should be ruled out if parturient is passing dark blood clots
placental abruption
150
best pain management option for term parturient with severe aortic stenosis
opioid only neuraxial
could do opioid only CSE
## Footnote
if pt requires c-section, GA is the gold standard
