• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/144

Click to flip

144 Cards in this Set

  • Front
  • Back
Oxygen consumption increases by _____% during pregnancy due to the metabolic needs of the fetus, uterus, placenta and secondary to cardiac and respiratory work
O2 consumption increases 30-40%
How much does the toracic cage circumference increase during pregnancy?
5-7 cm
Epistaxis and bleeding during DL may occur because of ________ and ______ of the upper airway
Venous engorgement and edema of upper airway
What are the leading causes of anesthesia related maternal morbidity and mortality during pregnancy?
Failure to intubate or ventilate and aspiration
Airway conductance ______ during pregnancy
increases
How much does TV increase during pregnancy?
45%
When does FRC decrease during pregnancy?
After the 5th month, decreased expiratory reserve leads to rapid and pronounced desaturation
How much does minute ventilation change during pregnancy?
Minute ventilation increases 45% d/t increased TV
What happens to respiratory rate during pregnancy?
Remains unchanged or decreases up to 15%
What is the average PaCO2 of a pregnant woman? When does this occur?
PaCO2 decreases to 30 mmHg by 12th week
What happens to PaO2 during pregnancy? When is PaO2 highest?
PaO2 increases; highest in 1st trimester
What happens to PaO2 in the supine position?
PaO2 falls below 100 in supine position
What happens to HCO3 during pregnancy? Why?
Decreases to compensate for respiratory alkalosis
What 5 cardiac measures increase during pregnancy?
CO, SV, HR, LVEDV, EF all increase
Where is blood shunted to during pregnancy?
Kidneys, uterus, breasts, and skin
What 2 cardiac measures/values decrease during pregnancy?
SVR and MAP decrease
How much does uterine blood flow change during pregnancy?
Increases from 50ml/minute to 700 ml/minute
How much does O2 consumption change during pregnancy?
Increases 20%
What happens to arterial pH during pregnancy?
Does not change; respiratory alkalosis (paCO2 30-32) offset by decreased bicarb (16-21 meq/L vs. 24 nonpregnant)
When do hemodynamic changes start to occur
by 8-10 weeks
How much has maternal CO increased by 32 weeks gestation? Immediately postpartum?
32 weeks- has increased 30-50%; immediately postpartum has increased 75-80%
How much does stroke volume change during pregnancy? HR? MAP? Blood volume?
SV: increases 30%
HR: Increases 15%
MAP: decreases 10-15%
Blood Volume: increases 35-45%
Cardiac output is highest:
just after delivery (75% above predelivery values for the first hour post-delivery) and remains elevated above predelivery values for first 48 hours
Venous return _____ during pregnancy
Increases
Total peripheral resistance ______ by _____% during pregnancy
Total peripheral resistance decreases by 15%
What are some expected cardiac auscultation findings during pregnacy?
Accentuated and split S1, normal S2, Systolic ejection murmur (present in 90%); diastolic flow murmur (in 20%), S3 heart sound (in 80%), occasional S4
Plasma volume _____ by _____% during pregnancy, while RBC volume ______ by _____%
Plasma volume increases 55% and RBC volume increases by 30%
Total blood volume increases _____ during pregnancy. Plasma volume increases _______ than RBC volume leading to ________.
Blood volume increases 45%; plasma volume increases more than RBC volume, leading to a dilutional/relative anemia
Platelet count is ____ during pregnancy
Stable- plateley consumption and production both increase
Plasma proteins are _____ during pregnancy
Diluted
Plasma cholinesterase _____ during pregnancy and does not return to normal until ______ weeks postpartum
plasma cholinesterase decreases and does not return to baseline until 6 weeks postpartum
What is the anesthetic implication of decreased plasma cholinesterase during pregnancy ?
Low to low-normal dose of succinylcholine; will have prolonged duration of action from sux
Albumin ____ during pregnancy, causing decreased plasma _______
albumin decreases, causing decreased plasma oncotic pressure- leading to edema
Pregnant patients are ____coagulable
hypercoagulable
All clotting factors increase during pregnancy except _____ and _____.
XI and XIII
The supine position causes _____ occlusion during pregnancy (starting at ____ weeks)
IVC occlusion starting at 13-16 weeks, evident by 20 weeks
What percent of preganant women suffer from supine hypotension syndrome during pregnancy?
5% have parasympathetic response; remaining 95% respond to IVC occlusion and resulting decreased cardiac output by increasing vascular resistance to normalize BP
Compression of IVC in supine position is decreased once______
baby's head is engaged in pelvis
A patient suffering from supine hypotensive syndrome will experience
decreased BP, tachycardia, pallor, faintness
What are the diagnostic criteria for supine hypotensive syndrome? What is the treatment?
MAP decreases by more than 15 mm Hg and HR increases by 20 bpm (sustained); treatment is left uterine displacement position
What should pregnant women receive prior to surgery?
30 ml Bicitra 30-45 minutes prior to surgery
Severity of aspiration is influenced by the increased _____ and decreased ______.
Increased volume and decreased pH
OB patients at high risk for aspiration should receive _____ in addition to bicitra 30-90 minutes before surgery
Reglan
Pregnant patients should only be extubated when _____
fully awake
All pregnant patients are considered full stomach and require:
RSI with cricoid pressure, avoid PPV if possible
Liver enzymes (except alk phos) are _____
upper normal values
the gall blader emptying is ____ during pregnancy, leading to
slow gall bladder emptying leading to residual bile volumes and gall stones
GFR ______ by ____% during pregnancy
GFR increases 50% during pregnancy
Creatinine and BUN _____ during pregnancy
decrease
Kidneys _____ during pregnancy and ureters and renal pelvis ______
Kidneys enlarge during pregnancy and ureters and renal pelvis dilate
Glucose excretion by the kidneys is ______ during pregnancy
elevated glucose excretion
During pregnancy, insulin secretion _____ and tissue sensitivity ______
insulin secretion increases and tissue sensitivity decreases
Diabetogenic state of pregnancy is mediated by what hormone? How long does this state persist?
human placental lactogen (HPL); returns to normal within 24 hours post delivery
Does insulin cross the placenta?
No
Hyperglycemia in the mother leads to ______ in the fetus after delivery
rebound fetal hyperglycemia
Total T3 and T4 values increase by ____% during pregnancy, and free T3, T4 values ______
total T3, t4 increase by 50% but free T3 T4 remain unchanged
The thyroid gland _____ in size during pregnancy
size increased, but euthyroid state maintained
Pregnant patients have a _____ sensitivity to local anesthetics
Increased sensitivity
Pregnant patients have an increased dependence on the ______ nervous system
Sympathetic
The epidural space is decreased during pregnancy dye to _______
epidural venous engorgement
Increased abdominal pressure during pregnancy enhances _____ spread of local anesthetics
Transdural
Pregnant patients have exaggerated lumbar _____, allowing increased cephalad spread of local anesthetics
Lumbar lordosis
Pregnancy induced analgesia is mediated by
increased endorphins and enkephalins in the CSF and brain; peaks at term and can be reversed with intrathecal narcan
Increased reliance on sympathetic tone primarily effects
venous capacitance to counteract the adverse effects of uterine compression; peaks at term and returns to normal 36-48 hours postpartum
Extradural pressures are _____ during pregnancy
higher
CSF volume is _____ during pregnancy
decreased
How is blood flow to the uterus supplied?
Internal iliac flows to the uterine aftery; uterine and ovarian arteries supply placenta and 90% of flow "spurts" into the intervillous spaces
Uterine blood flow at term comprises about _____% of cardiac output
12%
Is uterine blood flow auto-regulated?
No
What is the equation for uterine blood flow?
(Uterine Arterial pressure- uterine venous pressure)/(uterine vascular resistance)
What factors will decrease uterine blood flow?
Hypotension (supine position, hypovolemia, post- sympathetic blockade); incresed venous pressure (contractions, hypertonic uterus (pitocin), seizures, etc), increased uterine vascular resistance (catecholamins, vasopressors (phenylephrine >ephedrine)
pregnant patients have _____ sensitivity to vasoactive agents
Decreased sensitivity
Alpha agonist drugs cause decreases in ______
Myometrial and placental blood flow
ACE inhibitors may cause _____ in pregnant patients
decrease uterine blood flow by dilating peripheral vascular beds and stealing flow away from uterus
Prostaglandin inhibitors _____ uterine blood flow
decrease
increased cAMP and cGMP cause uterine vessels to _____
dilate
_____ umbilical arteries take blood from the _____ to the ______
2 umbilical arteries carry deoxygenated blood from the fetus to the placenta
Oxygenated blood is carried from the placenta to the fetus by way of _____ umbilical ______
1 umbilical vein
Can most drugs cross the placenta? What factors influence their ability to cross?
Most drugs can cross the placenta; amount of transfer is based on molecular weight, lipid solubility, ionization, concentration gradient, protein binding, metabolism in the placenta (p450 enzymes), intervillous blood flow, thickness of the membranesm and ratio of maternal to fetal blood flow in a given area
Who's law describes the ability of drugs to cross the placenta?
Fick's Law of diffusion
Do not allow the mother's BP to fall below _____ of baseline values d/t risk of decreased blood flow to the fetus
20%
Fibrinogen _____ during pregnancy
Increases
WBC counts ______ during pregnancy to about ______
increase to 13,000
What is the average blood loss for a vaginal and CS delivery?
600 ml vaginal delivery, 1000 ml CS
LES tone _____ during pregnancy due to what hormone?
LES tone decreases due to increase progesterone and decreased motilin
Gastric emptying ____ during pregnancy d/t what hormone
Decreases d/t progesterone
Decreased plasma protein means that ________ drugs will have more free drug available
highly protein bound drugs will have increased availability of free drug
Pregnant patients have _____ sensitivity to aminosteroid drugs
incrased sensitivity
MAC is _____ in pregnant patients, and rate of induction is ______.
MAC decreased, rate of induction is increased
______ tone predominates in the first trimester
PNS/Vagal
Fetal heart tones can be heard with a doppler at _____ weeks and a fetoscope at _____ weeks.
10-12 weeks with doppler, 17-20 weeks with fetoscope
Fetal movement is felt at _____ weeks
20
Mean pO2 of fetal blood is
30 mm Hg
Fetal Hgb has ______ for O2
higher affinity
Normal FHR is _____
120-160 bpm
the baby's stations is describes where the ____ lies in relation to the ______
presenting part in relation to the ischial spines
The latent phase of Stage I has pain in what dermatomes? What type of block is good for this?
Visceral fibers at T11-T12 stimulated when contractions generate at least 25 mm Hg force; paracervical block works well for this
The active stage of labor generally starts at _____ cm dilation and pain is transmitted via what nerve roots?
4-5 cm dilation; pain from T10-L1
The late active phase starts at ______ cm dilation; _____ pain begins from the stretching of vagina,perineum, and pelvic floor. What block works well for this?
starts at 7-8 cm; somatic pain begins; pudendal block works well
Pain coverage for the late active stage of labor requires coverage from _____ to _____.
S2-S4 sensory block
Describe the level of block needed for each stage of labor
Latent: T11-T12 sensory block
Active: T10-L2 sensory block
Late Active: S2-S4 sensory block
Stage 2: delivery- redose epidural
Stage 3: T10-S4
What clotting factors increase during labor?
I, II, VII, X
Early decelerations are often caused by ______, and are a _____ finding
Head compression; normal finding
Variable decelerations are related to_______; they can often be treated with _______
Cord compression; can be treated by changing position
Late decelerations ______ a contraction and can be caused by _______
Late decelerations follow contractions; indicate utero-placental deficiency- ABRUPTION
A sinusoidal pattern on a fetal heart rate tracing indicates
Severe acidosis and fetal distress- terminal rhythm
______ fetal positioning causes back labor and more severe pain
ROP
What is the IV tocolytic of choice
MgSO4
How does Mg work?
Inhibits Ach at the neuromuscular junction and decreases the sensitivity of the motor end plate for Ach
Patients receiving Mg infusions are prone to _____ during regional anesthesia
Hypotension
MgSO4 _____ muscle relaxants
Potentiates
How do Calcium channel blockers work as a tocolytic?
Inhibits transmembrane calcium thereby reducing myometrial contractility
You attend a delivery of a pre-term infant whose mother had been receiving tocolytic therapy to prevent delivery. What do you expect?
Uterine hypotonia and increased bloeding
What level of block do you need for a tubal ligation? for a hysterectomy/D&C?
T6 for tubal; T10 for D&C/hysterectomy (or higher if abdominal)
The period of highest concern for teratogenicity begins at _____, peaks at ______ and gradually decreases and becomes minimal through day ______.
Begins at 15-18 days post-conception, peaks at 30 days, and gradually decreases and becomes minimal until days 55-90
N20 is contraindicated during pregnancy d/t concern about
Methionine synthetase and tretrahydrofolate inhibition causeing concern for DNA production and demyelination
What 3 maternal factors must be avoided at all costs to preserve adequate fetal hemodynamics?
Maternal hypoxia, maternal hypotension, and maternal hypercarbia
Benzodiazepines and N20 are pregnancy risk category ____ and should only be given _____
Cat. D; only give if life-threatening treatment needed (seizures)
NMB should be antagoinized with which anticholinergic during pregnancy?
Atropine- robinul does not cross the placenta
Local anesthetics disrupt transmission through what fibers before other fibers?
C and Agamma (basis of differential block)
ATPTPMVP
Autonomics, temperature, pain, touch, pressure, motor, vibration, proprioception
Epidural level is determined by _____ and _______
drug volume and position
Epidural effect (density) is determined by ______
Concentration of drug
A positive intravascular test dose is evidenced by:
Epi CV effect- HR increase >10bpm and T-wave flattening of 25%
Fetal bradycardia is more likely with which type of regional anesthetic?
SAB
Autonomic blockade d/t regional anesthesia may result in uterine hyperstimulation because:
Removal of catecholamines leaves oxytocin unopposed (if conservative treatment is ineffective, terb or NTG may be helpful)
PDPH is likely to be caused by puncture of the dura by a ______ needle
Quinke needle (cutting needles)
If a patient is receiving LMWH, you should wait at least ______ hours before performing a block d/t risk of _______
wait 10-12 hours d/t risk of epidural hematoma formation; after block. wait at least 2 hours for re-do and remove epidural catheter prior to first post-op dose
Baby should ideally be delivered within ____ minutes of uterine incision
2 minutes
______ is a useful induction drug in the hypovolemic pregnant patient
Ketamine
The two best choices to treat maternal hypertension are
Labetalol and hydralazine
What anti-hypertensives should be avoided in the pregnant patient?
Sodium Nitroprusside (crosses placenta- fetal hypotension); ACE-inhibitors may contrinute to "uterine steal" and may affect fetal renal function
What is the best treatment for hypotension in the pregnant patient?
Ephedrine (>neo)
What is the anti-coagulant of choice in the pregnant patient?
Heparin
Oxytocin causes uterine ______ and vascular _______
uterine smooth muscle constriction and vascular dilation
What is the indication and mechanism of Methergine use? What route?
Indication: uterine hemorrhage resistant to Pitocin- causes uterine smooth muscle constriction and vascular smooth muscle constriction- CANNOT GIVE IV
Normal fetal HR variability is ______ beats per minute
6-15 bpm
Fetal HR increases during contractions are considered
Reassuring
The neonate has ______% HgF
75-84
What are the four causes of postpartum hemorrhage?
4 T's:
Tone (uterine hypotonia)
Tissue (retained placenta or fragments)
Thrombin (DIC)
Trauma (uterine rupture)
Painful vaginal bleeding is a sign of
Placental abruption
Painless vaginal bleeding is a sign of
Placenta previa
Prostaglandin F2 Alpha (hemabate) causes
Constriction of uterine, GI, bronchial and vascular smooth muscle
Hemabate must be used with caution in
asthmatics