Unit 3 Flashcards
1
Q
Define SROM
A
Spontaneous rupture of membranes
2
Q
Define AROM
A
Artificial rupture of membranes
An amniotomy is artificially speeding up labor
3
Q
What is OA and OP in terms of fetal directionality?
A
OA = occipitus anterior - head is facing patient’s abdomen (ideal position)
OP = occipitus posterior - head is facing the spine, less ideal
4
Q
Define CLE, DPE and CSE
A
CLE = continuous labor epidural
DPE = dural puncture epidural
CSE = combined spinal/epidural
5
Q
What are the various things that para or “P” can represent when discussing a parturient?
A
A term, preterm, abortions (or other loss) and living children
6
Q
What are 2 functions of the amniotic sac?
A
Protection of uterine contents from bacteria and mechanical protection for fetus and umbilical cord
7
Q
How long does the first stage of labor last for a Primip? Multip?
A
P = 8 - 12 hours
M = 5 - 8 hours
8
Q
What changes occur during the latent phase of labor?
A
Cervical effacement (cervix starts to thin)
Minor cervical dilation -> 2-4 cm
Contractions every 5-7 mins & duration 30-40 secs
9
Q
What changes occur during the active phase of labor?
A
Cervix dilates to 10 cm and contractions occurs every 2 - 5 minutes and last 50 - 70 seconds
10
Q
What 2 phases make up the first stage of labor?
A
Latent and active phases
11
Q
How long does the second stage of labor last?
A
15 - 120 minutes
12
Q
What factors are characteristic of the second stage of labor?
A
Fully dilated cervix, contractions every 1.5 - 2 minutes that last 60 - 90 seconds, fetal descent and ends with delivery of the fetus
13
Q
When is the second stage of labor considered prolonged?
A
If it is longer than 3 - 4 hours
14
Q
What are the risks of prolonged labor?
A
Cephalopelvic disproportion (kids head is too large)
Risk of fetal trauma
Severe umbilical cord compression possible
Maternal trauma (physical & emotional)
Increased risk for postpartum hemorrhage
Increased risk for infection
Increased admission to NICU
15
Q
How long does the 3rd stage of labor last?
A
15 - 30 minutes
16
Q
What characterizes the 3rd stage of labor?
A
Begins after delivery
Ends with delivery of placenta
Prolonged after 30 minutes
17
Q
How long does the fourth stage of labor last?
A
It is the first hour postpartum and carries the risk of uterine atony and postpartum hemorrhage
18
Q
What factors can affect labor pain?
A
Variable
Complex
Genetic influence
Pelvic size & shape
Fetal presentation
Natural labor / induction of labor / augmented labor
Most women c/o severe pain during contractions & with pushing
19
Q
What types of pain are experienced during the first stage of labor (include the receptors and fibers stimulated)?
A
Visceral pain - unmyelinated C nerve fibers transmitting pain signals from stimulated mechanoreceptors from the stretching/distention of lower uterine segment/cervix
20
Q
The pain fibers that transmit visceral pain from the cervix enter the spinal cord from what levels?
A
T10 - L1
21
Q
The latent phase of labor is affiliated with pain transmitting from what levels of the spinal cord? Active phase?
A
Latent = T10 - 12
Active = T12 - L1
22
Q
Visceral pain during stage 1 is difficult to treat with opioids but is amenable to what treatment?
A
Blockade of peripheral afferent nerves
23
Q
Stage 1 of labor is affiliated with what type of pain? Stage 2?
A
1 = visceral pain
2 = somatic pain
24
Q
How does pain differ in stage 2 of labor relative to stage 1?
A
Somatic pain becomes more prominent, transmitted by myelinated A-delta fibers via the pudendal nerve, sharp/easily localized
25
Somatic pain during the 2nd stage of labor is primarily transmitted by what nerve?
Pudendal nerve
26
What levels are of the spinal cord are associated with pain during the 2nd stage of labor?
T12 - S4
27
T/F: Visceral pain is still significant during the 2nd stage of labor
True; Somatic pain is more prominent but visceral pain is still a factor
28
How does sterile H2O injections help treat labor pain?
The theory is that it helps the body release endorphins
29
How does counterirritation help augment labor pains?
Providing a counter painful stimuli, such as squeezing a hair comb provides a physiologic distraction and helps augment pain by the gate control theory of pain
30
Who famously used chloroform to anesthetize queen victoria during labor?
John Snow
31
Who first described N2O use?
Stanislav Klikovitch
32
How does nitrous augment pain?
Inhibitory action at NMDA glutamate receptors
Stimulates dopaminergic, opioid & ⍺1 & ⍺2- adrenergic receptors
33
Why is nitrous an advantageous source of pain control during labor?
No decrease in uterine contractility or neonatal depression
34
What is a hard-stop to a patient receiving self administered nitrous?
Having an epidural in place
*Mentioned in lecture, it is not on the slide*
35
What nerve block can be combined with nitrous to provide analgesia?
Pudendal nerve block
36
Why should opioids be avoided if using nitrous?
The combo can cause hypoxia and loss of airway reflexes
37
Common s/e of nitrous use?
Nausea, dizziness, paresthesias, dry mouth
38
What effect do inhaled anesthetics (other than nitrous) have on uterine smooth muscle tone?
They have a dose-dependent smooth muscle relaxation effect
39
When is the max effect of tylenol?
1 hour
*Weak inhibition of COX 1/2 receptors*
40
What pregnancy related conditions are a contraindication to receiving ketamine?
Pre-eclampsia and/or HTN
41
What is ketamine a derivative of?
Phencyclidine
42
Why are BZDs used sparingly in labor?
They cross the placenta and can cause maternal/neonatal respiratory depression and neonatal hypotonicity with impaired thermoregulation
43
What are the pros/cons of opioid use in labor?
Advantages:
Ease of administration, low cost, no need for specialized equipment or personnel
Disadvantages:
N/V, sedation, placental transfer to fetus
44
Why is meperidine avoided in labor?
Lipid soluble (meaning it can easily cross the placenta), has multiple s/e and has an active metabolite - normeperidine
45
Is morphine hydrophilic or lipophilic?
Hydrophilic
46
Do lipophilic or hydrophilic drugs tend to cross the placenta?
Lipophilic
47
What is the PCA dose of Remi?
20 - 40 mcg w/2 - 3 minute lockout
48
What drug has improved analgesic scores over fentanyl?
Stadol
49
What opioid agonist/antagonist may cause fetal bradycardia that is responsive to narcan?
Nubain
50
Why is toradol avoided in labor?
Suppresses uterine contractions
Promotes premature constriction of fetal ductus arteriosus
Inhibits platelet aggregation
In general, avoid during labor
51
What type of block can help with stage 1 labor pains?
Paracervical block
52
What complications must be considered with a paracervical block?
Maternal complications include LAST & syncope
Risk of injection into fetal scalp
53
With a paracervical block, what is the most severe complication? Most common?
Severe = LAST
Common = fetal bradycardia
54
What are contraindications to a paracervical block?
Uteroplacental insufficiency or non-reassuring fetal heart rate
55
What must be performed prior to any neuraxial anesthesia intervention?
Consent must be obtained
56
T/F: routine lab testing is required for all parturients?
False: it is not required for healthy parturients
57
When is the optimal timing to obtain informed consent for neuraxial anesthesia?
Before labor, or early in labor
58
What monitoring equipment is not required when performing neuraxial anesthesia?
EKG
59
How often do you cycle BPs when for neuraxial anesthesia?
Cycle 1-5 minutes during initial stage of dosing
Change cycle to 15 minutes after initial 20-30 minutes
60
How is FHR monitoring documented when performing neuraxial anesthesia?
Fetal Heart Rate/Fetal Heart Tones
Continuous monitoring during & after placement
Document pre & post FHR
61
What are the advantages of lateral position for neuraxial anesthesia?
Less risk of intravascular catheter d/t epidural veins decompressed
May be easier for parturient
62
How does the apex of thoracic curvature change at term?
Shifts from T8 to T6
*This matters are this increases the risk of cephalad spread*
63
How does lumbar lordosis associated with pregnancy affect the intervertebral gap?
It shortens it, making it a "tight space" and harder to get your needle into
64
Absolute contraindications to neuraxial anesthesia?
Patient refusal
Uncooperative patient
Uncontrolled hemorrhage w/ hypovolemia
Epidural site skin/soft tissue infection
Moderate to severe bleeding issues/clotting disorder
Anticoagulation
65
Relative contraindications to neuraxial anesthesia?
Elevated ICP d/t mass lesion
Local anesthetic allergy
Language barrier w/o interpreter
Severe fetal depression
Severe maternal cardiac dz
Active coagulopathy
Untreated systemic infection
Pre-existing neurologic deficit
Skeletal anomalies
Hardware in spine
66
What are the risks of too early placed neuraxial anesthesia?
Risk for Instrumented delivery (Vacuum or forceps)
Prolonged second stage of labor
Risk for epidural becoming ineffective and needing
to be replaced
67
What are the risks of too late placed neuraxial anesthesia?
Patient can no longer get into a good position
Patient can no longer stay still
Provider preference
68
What are the 5 options for neuraxial anesthesia?
Epidural (CLE)
Dural puncture epidural (DPE)
Combined spinal-epidural (CSE)
Single shot spinal / intrathecal
Continuous spinal / intrathecal
69
What levels are an epidural generally placed?
L2 - 5
70
Advantages of a CLE?
Continuous analgesia
No dural puncture required
Catheter for c-section use
71
Disadvantages of a CLE?
Slower onset of analgesia, 10-15 minutes
Amount of local anesthetic/opioids required
Risk of sacral “sparing” or slow blockade
Greater risk for maternal LAST
Greater fetal drug exposure
72
What are 2 risks to using air for LOR?
Risk of patchy block with LOR to air
Risk for pneumocephalus with LOR to air
73
T/F: Evidence clearly supports air vs saline for LOR
False
74
Standard concentration in the CLE test dose?
1.5% lidocaine and 1:200,000 epi in 3 ml
75
How many mg of lido and epi are in the test dose?
1.5% = 15 mg/ml, 1:200,000 epi = 5 mcg/ml
Test dose = 3 ml
so 45 mg lido and 15 mcg of epi
76
What s/sx after the test dose indicate intravascular placement?
Increase HR 20 bpm within 1 minute (due to 15mcg epi), may have circumoral numbness or tinnitus (due to 45mg lidocaine)
77
What s/sx after the test dose indicate intrathecal placement?
Motor blockade in 3-5 minutes/warm or heavy legs (due to high dose of lido in intrathecal space), risk for high spinal!
78
Advantages of a CSE?
Rapid onset of analgesia, 2-5 minutes
Low doses of local anesthetic & opioid
Continuous analgesia w/epidural catheter
Epidural catheter to use for c-section
Decreased incidence of failed epidural
79
Disadvantages of a CSE?
Increased risk of fetal bradycardia (due to degree of sympathetic block and maternal hypotension)
Increased risk of PDPH
Increased risk of postpartum neuraxial infection
Uncertain of “correct” epidural catheter placement until block regression
80
What is the difference between a CSE and DPE?
Similar, but no medications are injected into the dural space, it just allows the epidural medication to "leak" into the dural space from the small nick/hole that is created
81
Advantages of a DPE?
Faster onset than an epidural without a DP
Transdural migration of medications injected into epidural space
More rapid sacral analgesia than traditional epidural
Decreased risk of maternal hypotension & fetal bradycardia compared to CSE
82
Disadvantages of a DPE?
Increased risk of PDPH
Increased risk of postpartum neuraxial infection
83
Pros/cons of single shot spinal?
Pros:
Rapid onset of analgesia
Immediate sacral analgesia
Low local anesthetic & opioid dosages
Cons:
Limited duration of analgesia (Based on local anesthetic & opioid selection)
Increased risk of maternal hypotension/fetal bradycardia
Increased risk of PDPH (Dependent on needle type / size / attempts)
Increased risk of postpartum neuraxial infection
84
When is a continuous spinal generally placed/used?
During unintentional dural puncture with a Tuohy
85
Pros/cons of a continuous spinal?
Pros:
Continuous analgesia
Low doses of local anesthetic/opioid
Rapid onset of analgesia
Can use if patient requires c-section
Cons:
Large dural puncture → risk of PDPH
Risk of mistaken identity!!!!
*You MUST clearly label the catheter as intrathecal and not epidural*
86
What safety measure MUST be taken when inserting an intrathecal catheter?
Clearly label it as intrathecal and use smaller doses than you would an epidural
87
What are the 2 most commonly used LAs for an epidural?
Bupivacaine and Ropivacaine
88
What are the advantages of Bupivacaine?
Differential block that spares A-alpha motor neurons, long duration, lack of tachyphylaxis and safe (limited placental transfer and unlikely to cause toxicity d/t low concentration)
89
Disadvantages of Bupivacaine?
Slow onset time ->10 – 15 mins
Latency is improved with lipophilic opioid
Risk of CV & neuro toxicity
Continuous epidurals commonly have an opioid mixed with it such as fentanyl
90
General dosing guidelines for Bupivacaine?
0.0625% - 0.25%
10-20 mL depending on concentration
Lower concentration / larger volume
Followed by maintenance infusion
91
Which LA provides a greater differential blockade relative to Bupivacaine?
Ropivacaine
92
Which LA has a higher risk of toxicity, Bupivacaine or Ropivacaine?
Bupivacaine
93
General dosing guidelines for Ropivacaine?
0.1 – 0.2% concentration
10 – 20 mL depending on concentration
Lower concentration / larger volume
Followed by maintenance infusion
94
Why is lidocaine not routinely used for labor analgesia?
Poor differential block (Significant motor involvement / blockade that is dependent on concentration & dose)
Risk of tachyphylaxis
Increased placental transfer / ion trapping
95
Pros/cons of 2-chloroprocaine?
Advantages:
Rapid onset
Short duration of action
Poor differential blockade
Disadvantages:
Interferes with action of bupivacaine / opioids
96
When is chloroprocaine useful/indicated?
Emergent instrumented or operative delivery/Perineal repair
*2 - 3% x 10 ml*
97
What combination of drugs/LAs is just as fast as chloroprocaine?
Lido with bicarb
98
How much do opioids reduce the dose of epidural LAs?
By 20 - 30%
99
What is the relationship of hydrophilic vs lipophilic when used in an epidural?
Lipophilic have a faster onset but are shorter acting
Hydrophilic have a later onset but last longer
100
What are 3 advantages to using opioids in your epidural?
Decrease latency
Prolongs duration of analgesia
Improves quality of analgesia
101
Pros/cons of Clonidine as an epidural additive?
Advantages:
Analgesic effect
Decreases local anesthetic requirements
Improves block quality & duration
No motor blockade
Disadvantages
Maternal hypotension & bradycardia
Maternal sedation
102
Advantages of precedex as an epidural additive?
Decreases local anesthetic requirements
Shortens latency
Prolongs duration of block
Higher concentrations:
Maternal sedation
103
What safety measure must be used with an epidural infusion?
Designated & dedicated infusion pump
Epidural tubing labeled & color coded
No injection ports
Less risk of bacterial contamination
104
What is the continuous epidural infusion dosing for bupivacaine and ropivacaine?
B = 0.05 - 0.125 % , 8 - 15 ml/hr
R = 0.08 - 0.2% , 8 - 15 ml/hr
105
Pros/cons to an epidural PCA?
Pros:
Patient self-administers based on need
Significant decrease in repeat dosing by provider
Cons:
Pump programming errors(Bolus dose volume
Lockout interval, Background infusion rate, Max allowable dose/hour)
Non-patient initiated boluses
Inappropriate clientele – don’t understand and keep pressing the button
106
Pros/cons of a background infusion rate of an epidural?
Background infusion benefits:
Better analgesia & increased maternal satisfaction
Less attentiveness required by pt
Background infusion disadvantages:
Increased total drug dose
107
What baricity of solution is typically used for a spinal?
Hyperbaric - to sink (Bupivacaine is typically 0.75% to make it hyperbaric)
108
What concentration of Bupivacaine is isobaric?
0.5%
109
A 5'6 female requiring a T10 block would get how much of 0.75% bupivacaine?
1.7 ml
110
If you give 1.7 ml of 0.75% bupivacaine, how many mg have you given?
1.7 x 7.5 = 12.75 mg
111
What impulses are not affected by spinal opioids?
Efferent impulses
112
What are 2 positives of adding precedex to a spinal?
Decreases latency and prolongs analgesia
113
What are 2 positives to adding epi to a spinal?
Prolongs analgesia
Higher dosing (100–200 mcg): Increased motor blockade
114
What are the infusion rates for Bupivacaine and Ropivacaine for a continuous spinal?
0.0625 – 0.125% bupivacaine +/- fentanyl 1-3 mcg/mL @ 1–1.5 mL/hr
0.1–0.2% ropivacaine +/- fentanyl 1-3 mcg/mL @ 1–1.5 mL/hr
115
What should you regularly assess after any spinal intervention?
Quality of analgesia
Progress of labor
Sensory level (Ice vs. “Pin Prick”)
Intensity of motor blockade
Maternal vital signs
FHR tracings
116
T/F: If the patient reports pain after a spinal, you should redo the spinal
False: not recommended d/t PDPH risk. Instead, place an epidural.
117
What factors cause hypotension after placing a spinal?
Sympathetic blockade
Peripheral vasodilation
Increased venous capacitance
Decreased venous return
118
What constitutes hypotension that requires treatment in a parturient receiving neuraxial anesthesia?
SBP < 90-100 mmHg or 20-30% decrease in baseline SBP (AND/OR FETAL DISTRESS)
*Treat with fluids, reposition and pressors*
119
What is a very common early s/sx of hypotension ?
Nausea
120
What is the most common s/e of an opioid being added to neuraxial anesthetic?
Pruritus
121
Why is benadryl a poor choice to treat opioid related itching?
The itching is unrelated to histamine
122
Treatment for opioid related itching d/t being added to neuraxial anesthesia?
A centrally acting mu-opioid antagonist: Narcan or naltrexone
123
What is the average depth to reach the epidural space?
4 - 6 cm
124
Good habits to use to prevent a wet tap?
ID ligamentum flavum while advancing Tuohy
Appreciate probable depth of epidural space
Advance Tuohy b/t contractions
Maintain control of needle-syringe always
Clear Tuohy of blood clots
125
Treatment of a wet tap?
Intrathecal cath or replace with epidural cath
Do not reinject CSF from syringe – risk for contamination/pneumocephalus
Epidural blood patch if headache develops vs. conservative treatment
126
What are the conservative treatments of a HA s/p wet tap?
Caffeine, lay flat, dark room
127
S/sx of intravascular epidural?
Tinnitus, circumoral numbness, restlessness, difficulty speaking, seizures, LOC
128
What is the lipid emulsion bolus dose?
1.5 ml/kg over 2 - 3 minutes, give a benzo as well
129
S/sx of a high spinal? Treatment?
S/sx = Agitation / dyspnea / inability to speak, sense of “impending doom”, Profound hypotension → loss of consciousness, Apnea
Treatment: Assist ventilation, Volume resuscitation, Vasopressors
130
What levels of the spine innervate the diaphragm?
C3 - 5
131
A patient reports pinky numbness s/p a spinal, how high has the spinal likely reached?
C8
132
What levels are the cardioaccelerator fibers found?
T1 - 4
133
Why does a subdural block carry such profound risk?
The space extends intracranially
134
S/sx of a subdural block?
Hypotension
Minimal motor blockade
Horners syndrome/apnea/LOC
135
Define macrosomia
fetus/newborn with excessive birth weight
136
Define TOLAC
trial of labor after cesarean
137
Define VBAC
vaginal birth after cesarean
138
Define PPH
postpartum hemorrhage
139
Define SAB
spontaneous abortion (or subarachnoid block)
140
Indications for operative vaginal delivery?
Nonreassuring FHR
Maternal exhaustion
Arrested descent
141
What changes to anesthesia may be needed for an operative vaginal delivery?
May need denser sensory block
Use higher concentration LA through in-situ epidural catheter
Lido 2% x 5-10ml
2-Choloroprocaine 2-3% x 5-10ml
142
What are 3 complications that increase mortality r/t a c-section?
Pulmonary aspiration
Failed intubation
Inadequate ventilation when requiring GETA
*Note that these complications are anesthesia related*
143
What factors increase c-section rate?
Increased maternal age & delayed childbirth
Obesity
Increasing incidence of macrosomia
Increased labor inductions
Fewer TOLAC attempts
Fewer instrumented vaginal deliveries
Increasing use of FHR monitoring
Concern for malpractice litigation
144
Common maternal c-section indications?
Arrested labor
Failed induction of labor
Chorioamnionitis
Active HSV lesions
Multiple gestation
Previous uterine surgery / classical incision
Maternal request
Antepartum/intrapartum hemorrhage
Uterine rupture
Placenta previa
Placental abruption
Deteriorating maternal condition
Pre-eclampsia
145
Common fetal indications for a c-section?
Malpresentation
Anomaly
Fetal intolerance of labor
Suspected macrosomia
Non-reassuring FHR
Category III
Prolapsed cord
Prematurity
146
What category of c-section necessitates GETA?
Emergency
*urgent may or may not*
147
Why is the low transverse incision preferred for c-sections?
Lower incidence of dehiscence or uterine rupture
Least painful
148
What is the advantage of a low vertical/midline incision for c-section?
Rapid access
*does have increased incidence of umbilical hernia*
149
What incision for c-section allows for the possibility of a TOLAC in the future?
Low transverse
150
In what c-section incision is any chance of TOLAC in the future contraindicated?
Classical incision
151
Why are classical incisions for c-section generally avoided?
Increased risk of abdominal adhesions
Uterine rupture risk ~10%
TOLAC contraindicated
152
What is the most common c-section complication?
Hemorrhage
153
T/F: GETA in c-section increased blood loss
True
154
What are the four T's of c-section complications?
Tone (this is the big one)
Trauma
Tissue (retained products)
Thrombin (coagulation status)
155
What are the contraindications to methergine and hemabate?
M = HTN
H = asthma
156
How much pitocin would you add to the IV bag?
10 - 20 units
157
How much and over what period of time would you give TXA in a c-section?
1 gram over 5 minutes
158
What are some possible interventions to treat maternal hemorrhage?
Bakri Balloon
Compression/B Lynch Suture
Uterine artery ligation
Hysterectomy
159
What condition occurs when the placenta blocks the birth canal?
Placenta previa
160
What condition(s) occurs when the placental tissues "gets into" or rather starts to grow into other tissues?
Placenta accreta/increta/percreta
161
What 3 complications are more likely for future pregnancies after a c-section?
Abnormal placental implantation, uterine rupture and hemorrhage
162
What interventions can help prevent an unplanned c-section?
Adequate labor analgesia for TOLAC & instrumented births
External cephalic version when appropriate – external manipulation
Prompt attention to non-reassuring FHT (keep baby happy)
163
What anesthesia is safest for mom/baby for a c-section?
Neuraxial
164
What factors can indicate a potential high risk delivery/c-section?
2nd (or 3rd or 4th…) c-section
Multiparity
Multiple gestation
Classical incision
Anemia
Maternal comorbidities
Abnormal placental implantation
165
What complication commonly is an indication for a central line?
Placenta accreta
166
What 3 meds common to pre-op are used to help reduce N/V and aspiration risk/severity?
Pepcid, Reglan and Bicitra
167
How much does bicitra change the pH?
Greater than 6 for about one hour
168
What are the 2 antibiotics of choice for a c-section?
Azithromycin 500 mg IV
Ancef 2 - 3 gm IV
*give slowly to avoid n/v*
169
What factors contribute to the decision to use versed before or after a c-section?
Discouraged - in general
Readily crosses placenta
Amnesia
Potentially interferes with bonding
BUT… may be beneficial for highly anxious parturients (give AFTER delivery)
170
T/F: maintaining an FiO2 of .35 - 0.4 helps improve fetal oxygenation
False
171
Advantages of neuraxial anesthesia?
Mother awake
Early bonding
Presence of support person
172
Disadvantages of neuraxial anesthesia?
Maternal discomfort
Nausea is not uncommon during a C-section
Pulling/tugging can be uncomfortable/cause anxiety
Under-surface of diaphragm (C3-5) is stimulated by cool/cold irrigation
Nausea, pain
Shoulder pain/chest pressure
Referred pain from uterine exteriorization
173
What is the triad of the bezold-jarisch reflex?
Vasodilation, Hypotension, Bradycardia
174
What receptors are responsible for the bezold jarisch reflex?
Mechanoreceptors in wall of LV responding to “low stretch”
175
What is the ideal timeframe to give zofran to mitigate the bezold jarisch reflex?
5 minutes prior to SAB
176
What can you do to prevent hypotension r/t neuraxial anesthesia?
Give Zofran
Phenylephrine 25-50 mcg/min infusion
Bolus doses of Phenylephrine and/or Ephedrine
Slight head up position (10 degrees)
Left Uterine Displacement
177
Why is hetastarch not commonly used?
Expensive
Risk for anaphylaxis
178
Other than crossing the placenta, what is the risk of using ephedrine?
Risk of reactive hypertension & umbilical artery metabolic acidosis
179
What is the ideal sensory level of neuraxial anesthesia?
T4
180
What factors influence the level of anesthesia achieved during neuraxial?
Baricity of local anesthetic solution
Hyperbaric
Isobaric
Patient position
181
What is the risk of using hyperbaric lidocaine in neuraxial?
Risk of transient neurologic syndrome (TNS)
Pain in legs & back 24 – 48 hrs after SAB
182
Advantages of using opioids in neuraxial anesthesia?
Improve quality of anesthetic block
Decreased incidence of intraoperative N/V
Decrease dose of local anesthetic
Prolongs postoperative analgesia
183
T/F: you can use more than 1 opioid in a spinal
True
184
S/e of neuraxial fentanyl?
Pruritus
Early respiratory depression
Maternal somnolence
185
S/e of neuraxial morphine?
Pruritus
Late respiratory depression
186
Treatment for neuraxial opioid related pruritus?
Treat with agonist-antagonist
Nubain/Stadol
Or central mu-opioid receptor antagonist
Naloxone/Naltrexone
*benadryl does NOT treat the itching*
187
Advantages of using precedex in a spinal?
5 - 10 mcg
Prolongs sensory & motor blockade
Postoperative pain control
Minimizes incidence of shivering
188
What spinal additive can help reduce the chances of shivering?
Precedex
189
What 2 drug related factors can influence the sensory level achieved from an epidural?
Volume and concentration
190
What are common effects/factors to consider when using 2% lidocaine in an epidural?
With or without epinephrine
Rapid onset, faster when bicarb is added
Short duration of action
Concentrations < 2% not adequate for surgical procedure
191
What are common effects/factors to consider when using 2-Chloroprocaine 2-3% in an epidural?
Very rapid onset & short duration of action
Metabolized by pseudocholinesterase
Antagonizes mu & kappa opioid receptors
Reduces efficacy of epidural morphine
192
What neuraxial drug reduces the efficacy of epidural morphine?
2-Chloroprocaine 2-3%
193
What are common effects/factors to consider when using Bupivacaine 0.5% in an epidural?
Intermediate onset
Long duration of action
Risk of cardiac toxicity
Bupivacaine 0.75% not used in epidurals
194
What are common effects/factors to consider when using Ropivicaine 0.5% in an epidural?
Intermediate onset
Long duration of action
Less risk of cardiac toxicity than Bupivacaine
195
How does NaBicarb affect an epidural?
More local anesthetic in non-ionized state
Speeds onset time
VERY useful when there is an urgent need to dose up an epidural to avoid GETA
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What additive is common to consider when you need to urgently dose up an epidural?
NaBicarb
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What medication can be helpful to eliminate a "hot spot" when dosing an epidural to surgical anesthesia level?
50 mcg of fentanyl
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What volume of LA can help extend the epidural to appropriate surgical anesthesia?
10 - 15 ml
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What must you do prior to giving extra LA in an epidural to achieve surgical anesthesia?
ALWAYS assess level
Allis test before incision
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Common indications for GETA in a c-section?
Fetal distress
Sustained fetal bradycardia
“Heart tones are down”
Maternal hemorrhage w/hypovolemia
Ex: Placental abruption
Ex: Uterine rupture
Neuraxial anesthetic not possible
Coagulopathy / thrombocytopenia
Infection
Patient refusal
Failed block/patient not tolerating
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Pros/cons of GETA in a c-section?
Pros:
Rapid onset
Secured airway
Hemodynamic stability
Cons:
Increased maternal mortality
Difficulty with airway management (Failed oxygenation/ventilation, Risk of aspiration)
Mother not awake during delivery
No “support person” in the OR (depends on policy/provider)
Potential anesthesia recall
Neonatal respiratory & CNS depression
1-minute APGAR scores lower with GETA
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What block may be helpful for pain control after a c-section under GETA?
TAP block
*Common to also need a pca*
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What size ETT is common for a c-section under GETA?
6.0 - 7.0
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When do you give Pitocin under GETA?
After delivery of fetus
Announce that you are giving it
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What MAC of gas do you use for GETA for a c-section after delivery?
0.5 - 0.75
*After delivery of fetus
Dose dependent decrease in uterine tone
Consider adding N2O to decrease volatile agent
Consider benzodiazepine administration to decrease recall
Titrate in opioids for pain control*
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What can hypocapnia cause? Hyper?
Hypo = Uteroplacental vasoconstriction
Oxyhemoglobin dissociation curve shifts left
Compromised fetal oxygenation
Hyper = maternal tachycardia
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When do you give BZDs and opioids for GETA for a c-section?
After delivery
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What drug potentiates NDMBs?
Magnesium
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What must you do prior to giving a NDMB following Sux administration?
Check twitches
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Common anti-emetics to use after GETA?
Scopolamine
Zofran
Phenergan
Droperidol
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What step is key to preventing aspiration prior to extubation in a parturient?
Suction the OGT
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What 3 drugs are used to treat uterine atony?
Pitocin/oxytocin, methergine and hemabate
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What are the characteristics of Pitocin?
Usually 10 units/mL concentration
20 units in bag AFTER umbilical cord is CUT
Stimulates uterine contractions
Hypotension/flushing – slow infusion
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What are the characteristics of Methergine/methylergonovine?
0.2mg IM or IV (Almost always IM)
CAUTION IN HYPERTENSION
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What are the characteristics of Hemabate/carboprost?
250mcg vial (1mL) given IM
CAUTION IN ASTHMA
May also cause massive diarrhea
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What drug used for uterine atony is an ergot alkaloid?
Methergine/Methylergonovine
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What drug used for uterine atony is a prostaglandin?
Hemabate/Carboprost
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How does hypotension cause N/V?
Cerebral & brainstem hypoperfusion → stimulation of medullary vomiting center
Gut ischemia → release of emetogenic substances from intestines
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How does surgical stimulation cause N/V?
Uterine exteriorization
Intra-abdominal manipulation
Peritoneal traction stimulation of vagal fibers
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How do uterotonics cause N/V?
Oxytocin = hypotension
Methergine = Interaction with dopaminergic & serotonergic receptors
Hemabate = this is the big one. It’s a prostaglandin which stimulates the GI tract -> Stimulation of GI tract smooth muscle
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Why does GETA for c-section carry a high risk for recall?
You have required periods of lower MAC
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What are common interventions to treat/deal with a high spinal?
Supplement with O2, moral support, pressors
May need to bag/mask
Loss of consciousness, respiratory drive, or refractory HOTN → GETA
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Shaking is common and hard to control, what may help treat it?
Meperidine or fentanyl may help
Some evidence for precedex
Giving mom something in her hand to squeeze on (ex: rolled up blue towel)
224
What LA used in an epidural is metabolized by plasma cholinesterases?
2-Chloroprocaine
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