OB: Anesthetic Complications in OB Flashcards
Anesthetic Complications in OB
Nausea and vomiting
Postdural puncture headache
Accidental intravascular injection
Accidental subarachnoid injection
Accidental subdural injection
EKG changes during regional anesthesia
CPR in the pregnant patient
Nausea and Vomiting
Regulated by the _______________________ zone and the ___________ center which are located in the area postrema and the medullary lateral reticular formation respectively.
chemoreceptor trigger
vomiting
Nausea and Vomiting
Nausea and vomiting may occur _____ or in _____ and are not uncommon in pregnancy.
separately or in combination
Nausea and Vomiting
Multiple causes have been implicated including:
- HCG
- Estrogen
- Progesterone
- Prostaglandins
- Immune system dysregulation
Hyperemesis gravadarum - When vomiting is sufficiently severe to produce:
- Weight loss
- Dehydration
- Acidosis from starvation
- Alkalosis from loss hydrochloric acid vomitus
- Hypokalemia
Intraoperative Nausea and Vomiting
_____ in incidence and presentation
Varies
Intraoperative Nausea and Vomiting
Incidence may be up to ____%
80
Intraoperative Nausea and Vomiting
Anesthetic causes of vomiting are ______________ and increased ___________ activity
hypotension
vagal
Intraoperative Nausea and Vomiting
Non-anesthetic causes include:
Surgical stimuli
Bleeding
Medications (uterotonic agents, antibiotics)
Motion at end of surgery
Intraoperative Nausea and Vomiting
Many of these elements occur ______
simultaneously
Nausea and Vomiting due to Hypotension
______ is among the most common sequelae associated with neuraxial analgesia
Hypotension
Nausea and Vomiting due to Hypotension
Centrally, hypotension may lead to _____ & _____ _____
cerebral and brainstem hypoperfusion
Nausea and Vomiting due to Hypotension
Peripherally, hypotension may cause ____ _____ with release of emetogenic substances from the intestine
gut ischemia
Nausea and Vomiting due to Hypotension
Strict maintenance of ______ _____ _____ can reduce the occurrence of emesis
intraoperative blood pressure
Oxytocin causes N/V due to hypotension from release of _____ _____ and _____ _____ _____
nitric oxide and atrial naturetic peptide
20% incidence of nausea, 10% incidence of vomiting after 5 u IVP
_____ ______ - (methergine) interacts with the dopaminergic and serotonergic receptors
ergot alkaloids
Hemabate causes nausea through the stimulation of _____ _____ of the ____ ____
smooth muscles
GI tract
10% incidence of nausea and vomiting after 250 mcg IM
N/V due to visceral pain pain from (3)
Exteriorization of uterus
Intraabdominal manipulation
Peritoneal traction
____ _____ > activation of vomiting center
Vagal fibers
general anesthesia-related factors:
- female
- hx of motion sickness or postop N/V
- nonsmoking status
- use of periop opioids
spinal anesthesia-related factors
- block height of T5 or higher
- hx of motion sickness
- hypotension
- omission of neuraxial opioids
Prophylaxis and Treatment of Nausea and Vomiting
Metoclopramide (Reglan) - _____ mg IV given ____ surgery or _____ cord clamping
Side effects: dizziness, drowsiness, fatigue. Rarely _____ and _____ _____
Can be given postpartum to increase milk production
10
before
after
EPS and acute dystonia
Prophylaxis and Treatment of Nausea and Vomiting
Ondansetron - ____ mg IV given after cord clamping.
Some studies show ______ risk of hypotension after spinal if Zofran given prior to block
Area for further future study: epidural Zofran?
4
decreased
Prophylaxis and Treatment of Nausea and Vomiting
Dexamethasone ___-___ mg IV, timing unclear, _____ _____ used for c-section patients
4-8
not regularly
Prophylaxis and Treatment of Nausea and Vomiting
Scopolamine - ____ mg transdermal patch after cord clamping. Can have ______ effects on breastfeeding
1.5
detrimental
Alternative therapies
Accupressure?
Supplemental O2?
Postpartum headache is the complaint of _____, _____ or _____ pain occurring during the first 6 weeks after delivery.
cephalic, neck, or shoulder
Postdural Puncture headache
Loss of CSF from within the dura and arachnoid membrane
Approximately ____ mL of CSF is present at a time
Approximately ____ mL is produced and reabsorbed every day
150
500
Postdural Puncture headache
_____ puncture > beveled spinal needle > ____ ____ spinal needle
Touhy
pencil point
Postdural Puncture headache
Dural fibers run _____ to ______
Implication for needle orientation
cephalad to caudad
PDPH: Clinical Appearance
- Relieved by lying down
- Returns on sitting up or standing
- Fronto-occipital, may be associated with ____/_____ stiffness
- _____phobia
- Less common: double vision, temporary deafness
- Onset is not usually immediate, may take ___-___ ____
neck/shoulder
Photo
1-2 days
PDPH Treatment
Conservative –
bedrest, oral or IV fluids, OTC analgesics
PDPH Treatment
Caffeine – _____ mg 90% of PDPH patients reported “significant improvement”
300
12oz RedBull contains 111 mg of caffeine
16oz can of Monster contains 160 mg of caffeine
PDPH Treatment
______ ______ block
Sphenopalatine ganglion
PDPH Treatment
Most effective (and invasive):
epidural blood patch
Liberal hydration doesn’t increase ____ _____, but dehydration does decrease
CSF production
_____ causes cerebral vasoconstriction
Caffeine
ECG Changes are ____ during routine c-section
common
Some correlation with ____ ____ and complaints of chest pain, pressure, nausea, vomiting or dyspnea
ECG changes
Few ST changes during regional anesthesia for cesarean delivery in healthy women are caused by _____ ______
myocardial ischemia
CPR in the pregnant Patient
Fetus does not tolerate decreases in maternal _____ or _____ ____ well
oxygenation or blood pressure
CPR in the pregnant Patient
Mother has high O2 _____ and low O2 _____ (residual volume)
demand
reserves
CPR in the pregnant Patient
Aortocaval compression – ____ _____ _____ is necessary to success
left uterine displacement
CPR in the pregnant Patient
Tilt decreases the ____ of ______
force of compressions
CPR in the pregnant Patient
Compressions should be _______ higher on the sternum
1-2 cm
CPR in the pregnant Patient
If patient has a neuraxial block substantially larger doses of ______ may be needed
vasopressors
CPR in the pregnant Patient
If a near-term parturient does not respond to resuscitative measures in 5 minutes emergent c-section is _______
_____ ______ to neonate
Relief of ______ compression for mom
recommended
Direct oxygenation
aortocaval
