OB Review* Flashcards
Pregnancy is usually ___ weeks long
40
This ___ of the respiratory tract mucosa and ___ will make airway management and intubation more difficult. Tissues will also be more ? - more bleeding.
~Plan on a difficult airway for pretty much every obstetric patient
vascular engorgement
edema
friable
Decreased bronchial airway resistance - this is in response to ___, even though you have some edema in the airways. The resting state for a pregnant woman is ___, so she will be blowing off her CO2 (30-32) but pH will remain normal.
Progesterone
hyperventilation
Additional Hyperventilation (even more than natural state) will drive down the CO2 even more, this can \_\_\_ your vessels. This will \_\_\_ the blood that is getting to the fetus thus you can get fetal distress. Why we give \_\_\_ = to decrease pain, to decrease hyperventilation
vasoconstrict
vasoconstrict
epidurals
To provide more oxygen, nutrients, blood flow to the fetus.
___ increases about 35%.
Increases ___ about 50%, but ___ only increases about 15-20%. Thus more plasma volume and less RBCs = ___.
Hgb 11-12 Hct 35% roughly
Blood volume
plasma volume
RBCs
dilutional anemia
- CO will increase about ___ in 1st TM
- ___ in 2nd TM
- ___ in labor, CO stays hyperdynamic about 6-9 hours post delivery
- Thus if these patients have any sort of cardiac disease this can be an issue - very hyperdynamic
30%
40%
50%
Considered Aspiration Risk at anything beyond ___ gestation and extending into postoperative period - will be considered a full stomach.
12 weeks
***The uterus oxygenated blood supply comes from the uterine artery and it feeds all the oxygen rich vessels of the uterus and those vessels grow into the placenta and this is where the oxygen exchange happens. And the supply to get to the fetus goes through the ___. Going from our artery to the fetus’ vein. This in the fetus, the vein, has oxygenated blood. This is also where the transfer of drugs happens.
umbilical vein
- Main mechanism of exchange across the placental membrane?
- Main drug factor influencing the rate of diffusion across the placenta?
- Diffusion
- Lipid Solubility
Maternal and Fetal Monitoring:
When giving an anesthetic and monitoring the mother…
Need to make sure the fetus is being monitored as well - catheter through the vagina or patches on abdomen will give us a fetal heart rate and it is looked at in relation to uterine contraction.
Generally there are 2 tracings ??
*Normally the FHR has some ___ in it - this is a good thing, heart rate should vary with movement etc (usually varies about 5-10 BPM)
1) FHR
2) Uterine contraction
- variability
Fetal Monitor Patterns - Normal FHR 120-160 BPM:
1) ___ = Usually due to fetus lacking nourishing blood supply or can see this with maternal fever, fetal infection or just gave the mother some drugs.
2) ___ = Onset and return of deceleration coincides with the start and end of the contraction. Associated with fetal movement, stimulation and uterine contractions. Usually happens from stimulation of the uterus or compression of head during contraction (vagal response) FHR goes back up once contraction is over. Reassuring pattern.
1- Tachycardia
2- Early Deceleration
Fetal Monitor Patterns - Normal FHR 120-160 BPM:
1) ___ = Fetal HR returns to baseline AFTER the contraction has ended. This is a little bit more worrisome. This happens with decreased uterine BF - mother is hypotensive, cord compression etc.
2) ___ = Even more ominous - FHR decreases at random times. This can be from head compression, cord compression. As it becomes more severe can be things like uteroplacental insufficiency.
1- Late Deceleration with Preserved Variability
2- Variable Decelerations
Fetal Monitor Patterns - Normal FHR 120-160 BPM:
___ = Severe decelerations have depth below ___ and a duration longer than ___. If persistent may lead to acidosis and fetal distress.
Severe Variable Decelerations
70 bpm
1 minute
- Fetal Bradycardia is any HR under ___.
* Caused from chronic maternal HTN, diabetes in the mother etc?
- 120
* Late Decelerations
There are 2 phases in Stage 1 = ??
___ is the longest phase.
___ = Anesthesia for this portion will be at a lower segment (?)
Latent and Active
Latent
Stage 2 (S2-S4)
- ___ is the most common narcotic used in OB - very effective analgesia. In general does not cause a lot of changes in FHR like some of the other narcotics but does cause some N/V.
- ___ can get some maternal respiratory depression and do get some fetal effects. Not used a lot - due to fetal effects like bradycardia.
- Pay attention to peak effect (giving far enough in advance of delivery or right before delivery???)
- Meperidine
* Fentanyl
___ - can increase ___ of ___. No real effect on ___ of labor. In general thought to be a good thing because it decreases all the detrimental effects of pain.
Do not want a ___ during second stage of labor because need pushing power (thus use a low concentration).
Epidural
Latent Phase of Stage 1
Active Phase
dense block
Epidural effects to discuss with patient:
- More at risk for ___-having a ___.
- Let patient know that in ___ they may feel more discomfort, decrease dose so they have the pushing muscles available.
- If epidural not adequate may need to change location or do it again.
Dural puncture
post-dural headache
Stage 2
Most common local anesthetics used??
The concentrations you are using are going to be really diluted out. Do not need surgical concentration - just want a little bit of analgesia. Rarely giving a full concentration of a local anesthetic.
~___ is spinal only - do not use in epidural space.
~___ is used because it is fast on and fast off.
Bupivacaine
Ropivacaine
~Tetracaine
~Chloroprocaine
Level you will need for a C-section?
T4
With the laboring parturient it is hard to appreciate a bump in the HR with test dose. Always make sure to give a test dose but give it ___ and really be diligent about watching VS and waiting appropriate amount of time before giving bolus.
between contractions
-___ = possibly from anatomic changes or the catheter migrated
~Look at catheter and see if distance has changed. Try ___ that the sparing or patchy block has occurred and try re-dosing your catheter. Or can give a ___ of your local anesthetic to try to counteract it. May need to be replaced.
-___ = not giving enough, so need to up your dose or your volume
-___ = conc. of LA is too high, need to decrease the concentration
-___ = turn off and start resuscitation (intubation, treating HDs etc.)
-Asymmetric or Patchy Block turning patient on the side higher concentration -Diminishing Analgesia -Dense Motor Block -High Epidural/Spinal Block
~Normal vaginal birth will lose about ___ of blood
~C-section losing about ___ of blood
~Less blood loss with C-section + regional (SAB) - ___
-Induction to delivery - when we are giving meds.
-___ = all Blood flow to the fetus is discontinued at this point
~500 mL
~700-1000 mL
~500 mL
-Uterine incision to delivery
N/V big sign someone is ___.
Patient complaining of nausea first thing you want to do is ___.
Hypotensive
check a BP
___ = from beginning of regular painful contractions of uterus to full cervical dilation and distension of the lower uterine segment.
- Pain is dull, aching and poorly localized
- ___ cm dilation
- ___ stage of labor (___)
- Most ___ pain (___ to ___ innervation)
- Slow conducting ___ enter SC at ___
First Stage
- 1 to 10 cm
- Longest (2-20 hours)
- visceral (T10-L1)
- visceral C fibers, T10-L1
___ = Distention of the pelvic floor, vagina and perineum from full cervical dilation to delivery.
- Pain is sharp, severe and well localized
- Most ___ portion of labor (___ pain at ___)
- Rapidly conducting ___ fibers enter SC at ___
Second Stage
- painful
- somatic pain at S2-S4
- A delta fibers
- S2 to S4
From the delivery of the neonate to delivery of the placenta?
Third Stage
Associated with Transient Fetal Bradycardia?
Sufentanil
Other Anesthesia Blocks:
- Used in first stage of labor? Associated with high rate of ___
- Used in second stage of labor?
-Paracervical block
fetal bradycardia
-Pudendal Block
- Increased ventilation at ___ gestation.
- Effects of maternal hyperventilation-usually prolonged = ___.
- Supine Hypotensive Syndrome - hypotension occurs ___ gestation d/t gravid uterus weight, can decrease CO by 30%.
- Venal caval compression = Decrease local anesthetic dose by 1/3 at ___ gestation.
- Aspiration prophylaxis indicated when pt is ___ gestation and immediate ___.
- 8 to 10 weeks gestation
- constriction of uterine and umbilical blood vessels
- > 20 weeks gestation
- > 14 weeks gestation
- > 12 weeks gestation and immediate postpartum period
Do not start a continuous infusion until satisfactory block is obtained at least a ___.
T10 level
___ = Compression of vena cava against the spinal column, lose the preload to the heart and results in hypotension (SBP less than 95)
*Management - ___, ___ and ___
Supine Hypotensive Syndrome
hydration
position change (LUD)
phenylephrine and ephedrine
