Section 4: Anesthesia for surgical procedures .. Flashcards
(209 cards)
1
Q
Robotic technology has defined itself
in the field of gastrointestinal laparoscopic
surgery and has made its way
into urologic, gynecologic and thoracic
surgeries, among others. List six {6} advantages of robot-assisted surgery from
the patient perspective.
A
(l) smallest possible incision;
(2) less surgical stress;
(3) less pain; •
(4) faster recovery;
(5) shorter hospital stays; and,
(6) improved overall satisfaction.
2
Q
State six {6) advantages of robot-assisted
surgery from the surgeon’s perspective
A
(1) less intraoperative blood loss;
(2) improved ergonomics;
3) enhanced and magnified 3·dimensional view of surgical field;
(4) superior manual dexterity (greater freedom of movement);
(5) decreased fatigue;
(5) filtering of resting hand tremor (reduced hand tremor); and,
(6) shorterlearning curve (compared to endoscopic techniques).
3
Q
Although robot-assisted surgery affords
many advantages to the patient and
surgeon, there are major anesthetic management considerations and
challenges. Positioning
A
There is risk of thromboembolism due to lengthy procedures in Trendelenburg position; use thromboembolic stockings to reduce risk. (2)
Maximize protection over pressure areas to avoid nerve injury and protect
face from direct pressure. .
4
Q
Difficulties inherent in patients having
prolonged surgery in Trendelenburg position are present: i
A
Increased mean arterial pressure in brain, increased cerebral blood volume, decreased cardiac output and perfusion to lower extremities, and decreased perfusion to vital organs. (
5
Q
ROBOTIC , There is potential common , nerve injury
A
peroneal nerve damage due to lithotomy position
6
Q
ROBOTIC Urine output
A
may be decreased and generally responds to fluid challenge.
7
Q
(5) Difficulties with peritoneal insufflation are present:
A
decreased compliance, increased airway pressure, increased ventilation-
perfusion mismatch, and hypercapnia. (6)
8
Q
PNEUMOPERITONEUM: Blood pressure reduction may be necessary secondary to resultant
A
increase in systemic vascular resistance because of the pneumoperitoneum.
9
Q
Describe the obturator reflex.
A
For low grade, non-invasive bladder tumors, a transurethral resection bladder tumor (TURBT) may be carried out via cystoscopy. Laterally located urinary bladder tumors may lie near the obturator
nerve- every use of the cautery resectoscope results in stimulation
of the obturator nerve producing violent contraction of the ipsilateral thigh
muscles and consequent adduction of the thigh (lower extremity), the so-called
obturator reflex
10
Q
TURBT differs from TURP in that the
A
surgical resection is not necessarily carried out in the midline.
11
Q
List two anesthetic techniques to abolish
the obturator reflex during transure·
thral resection of the bladder tumors
A
During transurethral resection of a laterally located bladder tumors (TURBT), every use of the cautery resectoscope results in stimulation of the obturator nerve producing violent contraction of the ipsilateral thighmuscles and consequent adduction of the thigh (lower extremity). «Urologists rarely derive amusement from having their ear struck by the patient’s
knee … “ (Butterworth).
12
Q
TURBT procedures are more commonly performed with (
A
1) general anesthesia and neuromuscular blockage or (2) neuraxia/ anesthesia to T9-TIO providing adequate anesthesia and preventing the obturator reflex
13
Q
Neuraxial anesthesia to prevent the obturator reflex
A
T9-T10
14
Q
What are four (4) goals of adding hyal·
uronidase to peribulbar local anesthetic
blocks?
A
Hyaluronidase added to an
ophthalmic block may: ( 1) improve the quality of the block; (2) increase
speed of onset; (3) limit the acute increase in intraocular pressure; and, (4)
decrease the incidence of postoperative strabismus
15
Q
What is a major dilemma in the patient
with an open eye-full stomach?
A
The dilemma in the patient with an open eye-full stomach is to protect the
patient from pulmonary aspiration and at the same time to protect the eye
from acute changes in intraocular pressure, which could cause vitreous
loss, retinal detachment, and blindness. In other words, you must weigh
the risk of aspiration against the risk of blindness.
16
Q
Describe the plan for induction in an
open eye-full stomach patient. Is succinylcholine contraindicated?
A
An open eye-full stomach scenario usually calls for a rapid-sequence induction; however succinylcholine raises intraocular pressure {IOP), as you know. However, at induction of general anesthesia, there are many activities that raise IOP to a much greater degree than succinylcholine,
including crying, Valsalva maneuver, forceful blinking, rubbing eyes, and
coughing or bucking. There are 2 key binary questions, in this order: ( l)
“Is this an easy airway?” If yes, then avoid succinylcholine and use highdose
rocuronium. If no, this is not an easy airway, then ask: (2) “Is the eye
viable?” If yes, then use succinylcholine
17
Q
Raise IOP to a much greater degree than succinylcholine,
A
including crying, Valsalva maneuver, forceful blinking, rubbing eyes, and
coughing or bucking.
18
Q
What volume of air (ml) will fill the
tracheal and bronchial cuffs of a double-
lumen tube?
A
The tracheal cuff of a double-lumen tube (DLT) normally requires 5-10 mL
air and can accommodate up to 20 mL of air. Inflation of the DLT bronchial
cuff requires l-2 mL air.
19
Q
The bronchial cuff is checked with a
A
3 mL syringe but rarely will the bronchial cuff require greater than 2 mL to createan adequate seal_
20
Q
Flexible fiberoptic bronchoscopy is essential to verify placement of a double-lumen tube (DLT), as you know. What feature of the endobronchial cuff facilitates visualization of this cuff during flexible fiberoptic bronchoscopy?
A
Bright blue, low-volume, low-pressure endobronchial cuffs are incorporated
on the double-lumen tube for easier visibility during fiberoptic bronchoscopy.
21
Q
Flexible fiberoptic bronchoscopy is
essential to
A
placement of a double-lumen tube (DLT)
22
Q
What is the location of the blue endobronchial cuff when a left-sided double- lumen tube is properly placed?
A
When a left-sided double-lumen tube (DLT) is properly positioned, the top
surface of the blue endobronchial cuff should be seen in the left bronchus,
approximately 5 mm below the tracheal carina (Nagelhout and Plaus state
1-2 mm below the carina). The blue endobronchial cuff should not be
too proximal or overinflated such that it herniates across the carina and obstructs
the contralateral bronchus or pushes the carina to the right.
23
Q
Identify the two (2) major perioperative goals for the patient with Graves’disease.
A
The most important preoperative goal for the patient with Graves’ disease is to make the patient euthyroid before surgery
24
Q
Grave’s disease: The other major perioperative goal is to
A
prevent sympathetic nervous system stimulation. This is accomplished by providing sufficient anesthetic depth and avoiding medications that directly or indirectly stimulate the sympathetic nervous
system.
25
Which agents must be avoided during induction in the patient with Graves'disease? Why?
During induction, avoid ketamine because it is a CNS stimulant. Also avoid pancuronium - it increases heart rate.
26
ECT play an important role in managing 3 things
Mania , depression, affective disorders
27
During ECT, the electrical stimuluar produces a
Grand mal seizure consisting of a brief TONIC phase followed by a more prolonged CLONIC phase.
28
Describe the CV response during clonic and tonic phases of ECT
The typical cardiovascular response to the ECT stimulus is 10-15 seconds of parasympathetic stimulation producing bradycardia, bradydysrhythmias and decreased BP( (the tonic phase) f/b sympathetic activation resulting in tachycardia, tachydysrhytmias and increase BP lasting for minutes.
29
How would you manage the tonic and clonic cardiovascular responses in ECT-
Initial parasympathetic effect of ECT can be prevented by premedication with glycopyrrolate, atropine. labetalol, esmolol and the calcium channel antagonists, nifedipine, diltiazem, and nicardipine can attenuate the hemodynamic responses to ECT
30
Initial parasympathetic effect of ECT are
Salivation, transient bradycardia, asystole
31
Define "hypertensive crisis" (hint: think
| arterial blood pressure measurements)
Hypertensive crisis is defined as arterial blood pressure ~180/120 mm-Hg
32
What differentiates hypertensive urgency from hypertensive emergency?
based on the presence or absence of impending or progressive target organ damage.Patients with chronic systemic hypertension can tolerate a higher systemic blood pressure than previously normotensive individuals and are more likely to experience urgencies rather than emergencies.
33
What is the treatment goal for the patient
| in a hypertensive emergency?
The treatment goal for the patient in a hypertensive emergency is to
decrease the blood pressure promptly but gradually. A general guideline is
to decrease arterial blood pressure by 20% to 25% within 30 to 60 minutes.
34
What is the drug of choice for hypertensive
| emergency
For most hypertensive emergencies, sodium nitroprusside {SNP) 0.5-10.0
mcg/kg/min IV is the drug of choice; however, treatment with SNP is
complicated by cyanide toxicity and lactic acidosis, as you know.
35
Other treatment alternatives for HTN emergency are
nicardipine, fenoldopam, esmolol, and labetalol
36
What recently FDA-approved drug may
be the new drug of choice for treating a
hypertensive emergency?
Clevidipine {Cleviprex), a third-generation dihydropyridine calcium channel blocker with ultrashort duration of action and selective arteriolar vasodilating properties has recently been approved by the Food and Drug Administration.
37
A third-generation dihydropyridine calcium channel blocker with ultrashort duration of action and selective arteriolar vasodilating properties
Clevidipine
38
What is the leading cause of postoperative
| hospital admission?
Inadequate pain relief is the # 1 cause of postoperative hospital admission.
39
Postoperative hypertension is common
and multifactorial; what factors contribute
to postoperative hypertension
Postoperative hypertension is common and multifactorial ... the multiple
causes of postoperative hypertension include: ( 1) respiratory compromise
or distress; (2) stimulation of the sympathetic nervous system; (3) visceral
distension; and, (4) volume overload.
40
What commonly used anesthetics agents
| have a favorable influence on bronchomotor tone?
Isoflurane, sevoflurane, propofol, ketamine, and midazolam all possess
bronchoprotective properties
41
Describe subglottic stenosis.
Subglottic stenosis can be acquired or congenital. Most cases are acquired
as a result of trauma associated with intubation, including damage to the
tracheal mucosa from direct injury during intubation, or improperly sized
TTs, or over inflation of the cuff
42
```
Immediately following extubation, a
patient shows signs of an upper airway
obstruction, indicated by loud snoring,
and retraction of the neck. What is the
best choice to alleviate the upper airway
obstruction in a conscious patient?
```
Nasopharyngeal airways are less stimulating than oropharyngeal airways
and are more appropriate for the awake patient. The nasal airway should
be well lubricated and gently inserted with the bevel facing the septum.
Complications include nose bleeding and care should be used during gentle
insertion.
43
What is laryngospasm?
Laryngospasm is a maladaptive over-exaggeration of the glottic closure
reflex. The glottic closure reflex is a protective mechanism in which adduction
of the cords occurs. However, in laryngospasm, the vocal cords are so
irritated by a noxious stimulus, that an intense exaggerated glottic closure
occurs {and may persist well after the noxious stimuli is gone), and results
in difficulty or the inability to ventilate the patient.
44
Administration of what drugs is indicat·
ed if postoperative inspiratory stridor is
due to laryngeal edema?
Inspiratory stridor due to laryngeal edema can be treated with the administration
of nebulized racemic epinephrine. Intravenous steroids ( cortisone)
may also be indicated. Rebound swelling may occur and therefore
observation should continue for up to 2 hours post treatment
45
What are the risk factors for pulmonary
| aspiration?
Risk factors for pulmonary aspiration include increased gastric fluid
volume with acid pH, delayed gastric emptying, decreased lower and upper
esophageal sphincter tone, and loss of laryngeal and pharyngeal reflexes.
46
What is the pharmacologic treatment for
| prevention of pulmonary aspiration?
The routine use of prophylactic drugs are not currently recommended,
however when specific risk factors (such as obesity, pregnancy, GERD, full
stomach) are present, the use of non-particulate antacids, pro-motility
drugs, and H1 antagonists can still be used alone or in combination. The
goal remains to decrease gastric volume while increasing gastric pH.
47
If prevention of aspiration is critical,
why have the fasting guidelines been
changed to be more liberal?
Research has shown that allowing clear liquids 2-4 hours before surgery
has actually decreased gastric volumes and increased gastric pH
48
Clear liquids,
2 hours
49
Breast milk,
4 hours
50
Infant formula,
6 hours
51
Fried or fatty meals,
8 hours or more.
52
What is the treatment for pulmonary
| aspiration once hypoxemia is evident?
Administer 02, only to the extent needed. Lidocaine 1.5 mg/kg as a neutrophil aggregate (improves long-term outcome). Intubate as needed. Bronchodilators, PEEP to support ventilation.
53
Diuretics should not be used to treat
pulmonary edema unless hypervolemia present.
54
Pulmonary aspiration, Antibiotics (only indicated if
fever longer than 48 hours or increased WBC greater than 48 hours.)
55
Pulmonary aspiration: Steroids are of
questionable benefit {prolonged hospital stay).
56
As the population ages and remains
physically active through their sixth
decade, major orthopedic joint replacement procedures
are increasingly more common.
57
Cementless ("press-in") prostheses
| generally (advantages
Last longer and may be advantageous for younger or more active
patients. In which patient population is a
cemented prostheses preferred
58
Cemented prostheses are generally preferred for ? why?
older (>80 years) and less
active patients because cementless ("press-in") prostheses require natural
bone to grow into them. Bone growth is more robust in younger and more
active individuals.
59
List nine (9) significant factors for
developing bone cement implantation
syndrome. CPAN PIL
(1) preexisting Cardiovascular disease;
(2) preexisting Pulmonary disease;
(3) ASA class 3 or greater;
(4) New York Heart Association Class 3 or 4; (
5) Canadian Heart Association Class 3 or 4;
(6) surgical technique;
(7) pathologic fracture; (8) intertrochanteric fracture; and,
(9) long-stem arthroplasty
60
Describe the treatment plan if bone
cement implantation syndrome (BCIS)
is suspected?
inspired oxygen concentration should be increased to 100% and
supplementary oxygen should be continued into the postoperative period. It has been suggested that cardiovascular collapse in the context ofBCIS be treated as right-sided heart failure. Aggressive fluid resuscitation is recommended
and hypotension should be treated with a-agonists
61
Treat HoTN in BCIS with
A-agonists
62
It has been suggested that cardiovascular collapse in the context of BCIS be treated as what?
right-sided heart failure
63
The trauma patient has suffered massive
blood loss and is unconscious. Describe
the fluid resuscitation for this patient.
Resuscitation of the patient in hemorrhagic shock should be initiated with
either whole blood or blood products
64
The trauma patient has suffered massive
| blood loss and is unconscious. What fluids should be avoided?
Avoid dextrose-containing solutions which may exacerbate ischemic brain damage
65
TRAUMA patient: If the patient's blood type is known,
administer type-specific whole blood or packed red blood cells (PRBCs).
66
TRAUMA patient If the patient's blood type is not known,
administer 0 -negative packed red blood
| cells (PRBCs)
67
TRAUMA fluid resuscitation advise a fixed ratio
(1 :1:1) of PRBCs, fresh-frozen plasma
| (FFP). and platelets to approximate whole blood
68
TRAUMA fluid resuscitation advise a fixed ratio
(1 :1:1) of PRBCs, fresh-frozen plasma
| (FFP). and platelets to approximate whole blood
69
TRAUMA resuscitation avoid
Avoid hydroxyeth· yl starch solutions (e.g. Hespan). which are associated with increased rates of renal replacement therapy and adverse events.
70
Fluid resuscitation is essential in the early care of the burned patient. State the
guidelines for fluid replacement when
the thermal injury is < 15% total body
surface area (TBSA)?
Fluid resuscitation for the burn patient with smaller burns ( < l 5% TBSA)
can be managed with replacement at 150% of the calculated maintenance
rate and careful monitoring of fluid status.
71
Is essential in the early care of the burned patient
Fluid resuscitation
72
For burn patients, lntravascular volume should be restored with utmost care to prevent
excessive edema formation in
both damaged and intact tissues resulting from the generalized increase in
capillary permeability caused by the injury.
73
```
Fluid resuscitation is essential in the ear·
ly care of the burned patient. State the
guidelines for fluid replacement when
the thermal injury is > 15% total body
surface area (TBSA
```
Fluid replacement for major burns ( > l S% TBSA) is given by the modified
Brooke formula, the Parkland formula, or the ABA
74
What fluids are preferred for the first day
| following thermal injury?
Crystalloid solutions are preferred for resuscitation during the first day
following a burn injury. In contrast to fluid management for blunt and pen·
etrating trauma, which discourages crystalloids, burn fluid resuscitation
emphasizes crystalloids, particularly lactated Ringers
75
Burn fluid resuscitation emphasizes
crystalloids, particularly lactated Ringers
76
Describe the modified Brooke formula
for fluid resuscitation in adults and
children >20 kg.
The modified Brooke formula for fluid resuscitation in adults and children
>20 kg is 2.0 mL lactated Ringers per kilogram per% TBSA burn for the
first 24 hours; one half in the first 8 hours, the other half in the next 16 hours
77
Describe the Parkland formula for fluid
resuscitation in adults and children > 20
kg.
The Parkland formula for fluid resuscitation in adults and children >20
kg is 4.0 mL lactated Ringers per kilogram per% TBSA burn for the first
24 hours.
78
Describe the ABA (American Burn
Association} consensus formula for fluid
replacement in adult burn patients.
The ABA (American Burn Association) consensus formula for fluid
replacement in adult burn patients is lactated Ringer's 2- 4 mL per kg body
weight per% TBSA burned.
79
What are the guidelines for fluid resus·
citation following thermal injury in the
first 24 hours for children <20 kg?
guidelines for fluid resuscitation in the first 24 hours for children <20 kg are crystalloid 2-3 mLlkg per% burn per 24 hours or crystalloid with 5% dextrose at maintenance rate of 100 mL/kg for the first 10 kg and 50 ml/kg for the next 10 kg for 24 hours
80
What colloid may be administered after
the first day following thermal injury? What is the rate of administration of this
colloid?
Albumin 5% may be administered after the first day following thermal
injury at a rate of0.3, 0.4, or O.5 m L/kg of the percentage burned per 24
hours for burns of 30% to 50%, 50% to 70%, or 70% to 100% TBSA, respec·
tively
81
List 3 cystoscopic and one entirely noninvasive therapies that have largely replaced open surgical and invasive treatment of kidney stones.
Kidney stones is now commonly treated by {I) flexible urteroscopy with
stone extraction; (2) cystoscopic stent placement; and, (3) intracorporeal
lithotripsy (laser or electrohydraulic). Medical expulsive therapy (MET)
has become the primary treatment of choice by many clinicians.
82
The treatment of kidney stones by 2 has
largely been displaced by less invasive
or entirely noninvasive procedures.
open surgical procedures and extracorporeal shock wave lithotripsy (ESWL}
83
Describe the medical expulsion treatment
| (MET) for kidney stones.
The medical expulsive therapy (MET) to promote ureter relaxation and
the spontaneous passage of small ureteral stones involves treatment with
calcium-channel blockers (e.g., nifedipine), a-blockers (e.g., tamsulosin,
doxazosin, or terazosin), and sometimes, corticosteroids.
84
Extracorporeal shock wave lithotripsy
(ESWL} is the treatment of choice for
• what two kidney stone situations?
Extracorporeal shock wave lithotripsy (ESWL) is the treatment of choice
for disintegration of intrarenal stones of 4-mm to 2 cm (nephrolithiasis) and
kidney stones in the upper part of the ureter (ureterolilhiasis).
85
```
First generation lithotripters required
patients be placed in a hydraulic chair
and lowered into a heated water bath to
create an interface between the shock
wave and the patient. What challenges
and complications are associated with
water-bath immersion during extracorporeal shock wave lithotripsy (ESWL)?
```
[n addition to the significant positioning maneuvers associated with the
water bath immersion during ESWL, patients are prone to hypothermia •
during the procedure. Dysrhythmias can be a special problem as the transmission
of the ultrasonic pulse is timed and triggered by the ECG. Significant
respiratory and hemodynamic changes are associated with immersion
and emergence from the water bath, which can be problematic particularly
for patients with cardiopulmonary diseas
86
List three (3) cardiovascular and five
(5) respiratory changes on immersion
in the water bath of a first-generation
lithotripter.
The cardiovascular changes upon immersion in the water bath of a
first-generation lithotripter are: ( l) increased CVP; (2) increased central
blood volume; and, (3) increased pulmonary artery pressure. Expected
respiratory changes include: (l) increased pulmonary blood flow; (2) decreased
vital capacity; (3) decreased FRC; (4) decreased tidal volume; and
(4) increased respiratory rate.
87
```
Second- and third-generation lithotripters
do not require immersion of the
patient in a water bath - these modern
"dry" SWL uses a smaller water-filled
coupling device to provide an interface
with the patient, which simplifies the
procedure considerably. There are still
complications associated with the shock
wave: list nine (9) complications from all
forms of shock wave lithotripters.
```
(l) Skin bruising and (2) flank ecchymoses can occur at the entry site. Painful (3) hematoma in the flank muscles may occur. (4) Hematuria is almost always present at
the end of the procedure and results from shock wave-induced endothelial
injury to the kidney and ureter. Adequate hydration is necessary to prevent
clot retention. (S) Lung tissue is especially susceptible to injury by shock
waves, as are the (6) colon and small intestines. (7) Diabetes, (B) new-onset
hypertension, or (9) permanently decreased renal function may also result.
88
```
State two (2) absolute contraindications
to shock wave lithotripsy (SWL).
```
Two absolute contraindications to shock wave lithotripsy are: ( l) bleeding
disorder or anticoagulation, and (2) pregnancy.
89
What are five (5) relative contraindications
| to shock wave lithotripsy (SWL)?
Five relative contraindications to shock wave lithotripsy (SWL) are: (I)
untreated (active) urinary tract infection; (2) large calcified aortic or renal
artery aneurysms; (3) obstruction distal to the calculi; (4) pacemaker, rco.
or neurostimulation implant; and, (5) morbid obesity. [
90
What special concern exists in chit
dren undergoing extracorporeal shock
wave lithotripsy? How is this concern
addressed?
Children are more likely to sustain pulmonary damage from shock waves
because of the shorter distance of the lung bases from the kidneys than
in adults. It is recommended that a Styrofoam sheet or Styrofoam board
be placed under the back in children to shield the lung bases from shock
waves during ESWL.
91
For a fire to occur, three components of
a 'fire triangle' must be present: list the
triad of components in the fire triangle.
a fuel source, an ignition source, and an oxidizer.
92
There are a number of ignition sources
in the operating room, most are under
the surgeon's control. List potential
ignition sources in the OR .
(1) lasers; (2) electrosurgery unit (ESU}; (3) argon beam coagulator; (4) fiberoptic illumination; (S) defibrillator; (6) pressure regulators; (7) surgical lights; and, (8) electrical lights
93
Define "fuel• and
A fuel is anything that burns. Fuels abound in the operating room, including
the patients themselves.
94
list examples of fuels in the operating room.
l) tracheal tubes; (2) supraglottic
airway devices; (3) drapes, towels, and dressings; (4} adhesives; (S)
skin preparatory solutions; (6) intestinal gases; (7) oxygen cannulas; (8)
petroleum-based lubricants and ointments; and, (9) body hair
95
What are the 2 most common oxidizers
| in the operating room
Oxygen and nitrous oxide are the most common oxidizers in the operating
room and are under control of the anesthetist.
96
A desiccated C02 absorbent can serve as
| one of the 3 components of the fire triangle- which one? Explain the process.
Desiccated C02 absorbent is a possible source of ignition in the breathing
circuit. When a desiccated strong base C02 absorbent is exposed to sevo·
flurane, absorber temperature of several hundred degrees may result from
their interaction.
97
Nitrous oxide supports
combustion and in the process releases the energy of its formation, providing
increased heat
98
In the case of the dessicated Co2 absorbent, can serve as one of the 3 components?
all the sub-strates necessary for a fire to occurThe buildup of very high temperatures, the formation of
combustible degradation byproducts (formaldehyde, methanol, and formic
acid), plus the oxygen· or nitrous oxide-enriched environment provide
99
List the sequence of steps to take to
| manage an intraoperative airway fire: 4 STEPS Barash (SPRM)
1) simultaneously remove the endotracheal tube and stop gases/disconnect
circuit;
(2) pour saline into airway;
(3) remove burning materials;
4)mask ventilate patient, assess injury, consider bronchoscopy, reintubate
100
The short Nagelhout and Plaus version:
( l} stop oxygen flow; (2) stop ventilation;
| (3) extubate patient; (4) extinguish fire; (5) mask ventilate; (6) reintubate.
101
After airway fire, The patient will require
airway assess·ment and medical treatment including bronchoscopy, lavage, and steroids
102
```
In the previous question, shorter versions
of airway fire management were
given; Nagelhout and Plaus provide a
more expansive 15-step version- list
these l S steps.
```
1} discontinue use of
laser; (2) in rapid succession, remove ETT, turn off all gases, remove sponges
and any flammable mate rial, and pour saline into airway; (3) extinguish
burning ETT/LMA in basin of water (always available during laser surgery);
{4) resume ventilation with air, ventilate with 100% Oz only when the fire is
extinguished; (5) examine airway and remove residual debris with rigid bron
choscope, consider lavage with normal saline, examine small and distal airways
with flexible fiberoptic bronchoscope; (6) administer humidified Oz by mask if
airway damage is minimal and risk oflaryngeal edema is low; (7) if indicated,
reintubate with a smaller ETT; (8) assess extent of thermal trauma with ABG,
carboxyhemoglobin levels, and CXR; (9) keep patient intubated and administer
40" to 6°'6 humidified Oz if airway burn is present or suspected; (10) consider
tracheostomy and mechanical ventilation for postoperative management; ( 11)
consider administration of steroids; (12) admit patient to ICU for a minimum
24·hour observation; (13) retain all equipment and materials involved in the
fire for further inspection; (15) reassemble surgical team to identify the se·
quence of events that led to the surgical fire; ( 16) report fire as a sentinel event
to The Joint Commission, ECRI, and the FDA.
103
List 6 factors that contribute to persistent
pulmonary hypertension of the
newborn (PPHN).
Hypoxia, acidosis, hypothermia, hypovolemia, pneumonia, and inflammatory mediators are primary factors that contribute to persistent pulmonary •
hypertension of the newborn (PPHN).
104
Identify conditions and risks that precipitate persistent pulmonary hypertension of the new born (PPHN).
Persistent pulmonary hypertension of the newborn (PPHN) is usually caused by precipitating conditions such as severe birth asphyxia, meconium aspiration, sepsis, congenital diaphrag-matic hernia, and maternal use of (NSAIDs).
105
Risk factors for Persistent Pulmomnary HTN of the newborn--
iclude maternal diabetes or asthma, and cesarean delivery
106
Describe pectus excavatum
```
Pectus excavatum (Latin "hollowed chest"), also known as "funnel chest':
is the most common congenital deformity of the anterior wall of the chest,
occurring in about 1 in 4000 children.
```
107
In most children in which pectus
| excavatum is an isolated deformity of the sternum, there are
no significant functional limitations; lung volumes and functions are preserved
108
```
List five (5) diseases with which pectus
excavatum is associated. When associated
with a congenital anomaly does pectus
excavatum contribute to obstructive
or restrictive pulmonary disease
```
```
Pectus excavatum is often seen with
Marfan syndrome
osteogenesis imperfect
mitral valve prolapse, mucopolysaccharidoses
nemaline rod muscular dystrophy.
```
109
When seen in conjunction with other congenital anomalies, pectus excavatum
decreases vital capacity and chest wall compliance
| and can result in arterial hypoxemia caused by V/Q mismatch this is a restrictive pulmonary disease pattern.
110
What endotracheal tube size is needed
| for the pediatric patient with epiglottitis?
Endotracheal intubation in the pediatric patient with epiglottitis is performed orally with a styletted tube one or two sizes smaller than usual.
111
What confirms the diagnosis of Epiglottis under direct laryngoscopy?
Visualization of the classic cherry-red epiglottis under direct laryngoscopy
confirms the diagnosis.
112
Which congenital anomaly is characterized
by a short neck, irregular dentition,
a high, arched palate, macroglossia,
micrognathia, and subglottic stenosis?
Patients with trisomy 21 (Down's syndrome) have a short neck, irregular
dentition, a high, arched palate, macroglossia, micrognathia, and subglottic
stenosis
113
What should be expected for patient with trisomy, macroglossia, etc
Airway obstruction and hypoxemia upon induction should be expected. Oral airways should always be available to help reestablish airway patency.
114
During neonatal and pediatric surgery,
every effort must be made to maintain
the infant's temperature to minimize
thermal stress.
To minimize the stress of hypothermia during pediatric procedures, the surgical environment should be warmed to ensure that the entire room constitutes a giant incubator.
115
Neonates and infants require about twice as much as succinylcholine mcg/kg as older children or adults. Give 4 reasons why neonates and infants are more resistant to succinylcholine than older children and adults.
Neonates and infants up to age 2 years are more resistant to succinylcholine for both pharmacodynamics and pharmacokinetics reasons.In respect to succ in adults, neonates and infants up to age 2 years have
1. ED 95 of 625 and 729 mcg/kg in other words 2 to 2.5 times GREATER THAN adults
2. faster clearance
3. Larger volume of distribution
4. shorter onset times
116
What operating room temperature is recommended for procedures on a full-term infant? For a premature infant?
Operating room temperatures of 27 °C and 29 °C are recommended for full-term and premature newborns, respectively.
117
What are the classifications of the hypertensive disorders in pregnancy (toxemia of pregnancy; pregnancy induced
hypertension)?
The classification of hypertensive disorders of pregnancy are:
-Gestational hypertension
-Preeclampsia: (1) preeclampsia without severe features, (2) severe pre- •
eclampsia (Edampsia)
-Chronic hypertension
-Chronic hypertension with superimposed preeclampsia
118
Define gestational hypertension.
Gestational hypertension, or pregnancy induced hypertension (PIH) is blood
pressure of 140/90 and above in an otherwise healthy woman after the 19"
week of gestation.
119
```
Define edampsia (preedampsia with
severe features).
```
Eclampsia is present if seizures or coma occur in the syndrome of pregnancy-
induced hypertension. Eclampsia is therefore defined as preedampsia
with severe features
120
What are the risk factors for preedampsia
Risk factors for preeclampsia include chronic renal disease, chronic hypertension,
obesity, nulliparity, family history of preedampsia, and advanced
maternal age.
121
What is the cause of preeclampsia?
The hallmark of preeclampsia is an abnormal placental implantation. This • abnormal placenta releases vasoactive substances causing dysfunction of
the maternal vasculature
122
What is the drug of choice for seizure prophylaxis in a patient with preeclampsia? why?
Magnesium sulfate is drug of choice for seizure prophylaxis in a patient with preedampsia. Magnesium sulfate is 5O% more effective in preventing new onset and recurrent seizures than other commonly used anticonvulsants
(i.e., diazepam, phenytoin).
123
The patient with preeclampsia is in danger of developing serious complications-Name eight (8) serious complications of preeclampsia?
```
Serious complications of preedampsia include:
(1) Pulmonary edema;
(2)airway obstruction;
(3) placental abruption;
{4) cerebral hemorrhage:
(5))cerebral edema:
(6) disseminated intravascular coagulopathy:
(7) HELLP
8) renal failure; and, {8} CHF
```
124
When does the HELLP syndrome usually occur? What should be done if this syndrome develops?
The HELLP syndrome usually occurs before 36 weeks gestation. Its diagnosis calls for immediate delivery, regardless of gestation due to high maternal and fetal mortality.
125
List medications used to blunt the
hemodynamic response to laryngoscoPY
and intubation during induction of
general anesthesia
Labetolol, esmolol, nitroglycerine, sodium nitroprusside, and remifentanil
are used to blunt the transient but severe hypertension that may accom- •
pany tracheal intubation during induction
126
Why is hydralazine a commonly used
| antihypertensive in preeclampsia?
Hydralazine is vasodilator that also increases uteroplacental flow and renal
blood flow. Nitroglycerine and labetalol are also commonly used.
127
Is regional anesthesia (epidural, spinal,
CSE) contraindicated in preeclamptic
patients?
Provided there is no severe clotting deficit or plasma volume deficit,
regional anesthesia can be safely used in the preeclamptic patient
128
What is the normal serum magnesium
concentration (mg/dL)? In mEq/L? In
mmol/L?
Normal serum magnesium is 1.8- 2.5 mg/dL (l.5-2.l mEq/L, 0.75-l.5
mmol/L}. (
129
What three (3) anesthetic considerations
must be taken in the parturient receiving
magnesium sulfate?
Magnesium sulfate: {l) causes prolonged duration and intensity of nondepolarizing
neuromuscular blockade; (2) causes uterine vasodilation
causing postpartum uterine atony and hemorrhage; and, (3) interacts with
calcium entry blocking agents.
130
What signs occur when serum magnesium
levels reach 7- 12 mgldL (4.2-5.8
mEq/L, 2.1- 2.9 mmol/L)?
Somnolence, loss of deep tendon reflexes, hypotension, and ECG changes
occur when serum magnesium levels reach 7-12 mg/dL (4.2-S.8 mEq/L,
2.1- 2.9 mmol/L}.
131
What signs occur when serum magnesium levels reach 12 mg/dL (10 mEq/L,
5 mmol/L)?
Complete heart block, cardiac arrest, apnea, paralysis, and coma.
132
Once the fetus and placenta are delivered
the mother is no longer at risk for
complications of preeclampsia. True or
False?
FALSE. The risks of preedampsia do not end with delivery. Pulmonary
edema, stroke, embolism, airway obstruction, and seizures are a significant
risk postpartum. Severe preedampsia, HELLP, and edampsia can present
FOR THE FIRST TIME in the postpartum period, sometimes as late as 4
weeks after delivery
133
Which drugs commonly used in anesthesia
| readily cross the placenta
Most drugs including many anesthetics readily cross the placenta. These
include, but are not limited t
134
Does Atropine cross placenta?
yes
135
Does VA cross the placenta?
yes
136
ketamine, etomidate, thiopental, crorss placenta?
Yes
137
Does ephedrine cross the placenta?
yes
138
Do diazepam and midazolam cross the placenta?
yes
139
Does Opioids cross the placenta?
yes
140
Do beta blockers cross the placenta?
yes
141
Do LA cross the placenta?
Yes
142
Vasodilators that cross the placenta?
NTG, nitroprusside
143
Which medications used commonly
during anesthesia do not cross the
placenta and would need to be given
directly into the fetal vein?
Glycopyrrolate, heparin, depolarizing and nondepolarizing muscle relaxants,
and phenylephrine do not cross the placenta and would need to be
given directly into the fetal vein.
144
Pressor medication not crossing the placenta?
Phenylephrine
145
What is the key determinant of the
amount of drug transferred across the
placenta?
The maternal blood concentration of free drug is the primary determinant
of the amount of drug transferred across the placenta. Remember:
Higher doses result in higher maternal blood concentrations
146
What are the four ( 4) key factors that
influence the rate of drug diffusion to
the fetus?
1. The physiochemical characteristics of the drug (protein binding, molecular weight, lipid solubility); (2) the dose and mode of administration (epidural vs. IV); (3) placental maturation; and, (4) the hemodynamic events within the fetomaternal unit.
147
Maternal-fetal exchange of most
| drugs occur primarily by.
diffusion, favoring the transfer of drugs with low molecular weight (less than 100 Daltons) and high lipid solubility
148
are considered less free for diffusion across the placenta
Highly protein bound drugs
149
Which is more lipophilic, the ionized or
| nonionized form of a drug?
The nonionized form a drug is more lipophilic and can more easily pass
through biologic membranes.
150
What is the effect of intravenous (IV)
| lidocaine on uterine blood flow?
All local anesthetics can reduce uterine blood flow at HIGH plasma concen·
trations. High doses of IV lidocaine cause uterine arterial vasoconstriction
and increased uterine tone
151
Low levels of circulating lidocaine do not
produce vasoconstriction.
152
Magnesium sulfate is a commonly used
drug in pregnancy. Name 3 advantageous
effects of magnesium sulfate in pregnancy.
Magnesium sulfate is a tocolytic, an anticonvulsant, and a fetal neuropro·
tective agent
153
Why is sodium bicarbonate routinely
added to prepackaged lidocaine with
epinephrine for epidural anesthesia
prior to cesarean section?
Alkalization of the local anesthetic hastens the onset of neural block and
improves the quality of the block. Commercial preparations oflocal anes- •
thetic, especially those containing epinephrine, are acidic. Adding sodium
bicarbonate increases the amount of drug in the lipid soluble form (nonionized
form), thus increasing the rate of diffusion across lipid membranes.
154
Sodium bicarb cannot be added to
bupivacaine as it will precipitate.
155
What is the impact of adding epinephrine
to local anesthetics used for epidural
anesthesia during cesarean section?
Adding vasoconstrictors such as epinephrine to a local anesthetic prolongs
the duration of the block, increases the intensity of the block, and decreases
systemic absorption.
156
What is the drug of choice for treatment
of hypotension during a cesarean
section? Why?
Ephedrine AND phenylephrine can both be titrated safely to maintain
blood pressure in the parturient. Historically, alpha-agonists (phenylephrine)
were avoided over concerns of decreased uterine blood flow by vasoconstriction. Phenylephrine in small doses (40 mcg) is recommended.
157
When is ketamine used for cesarean
| section? Specify the ketamine dose.
Ketamine (lmg/kg) is preferred for induction if the mother is hypovolemic
due to its hypertensive effects. The maximum dose of ketamine for rapid
sequence induction of the parturient is 1 mg/kg.s. Ketamine at doses of 0.25-0.5O mg/ kg IV produce rapid analgesia for labor and delivery.
158
Higher doses of Ketamine with fetus.?
At higher doses, ketamine increases uterine tone and could endanger the fetus
159
Does ketamine cross the placenta?
Ketamine crosses the
| placenta due to its high lipid solubility.
160
Ketamine given too dose to delivery can cause
respiratory depression and muscular hypertonicity resulting in lower Apgar scores.
161
Besides induction oflabor, what else is
oxytocin routinely used for in obstetric
anesthesia?
Oxytocin is the first-line treatment for uterine atony. Oxytocin stimulates
uterine smooth muscle and is routinely given intravenously immediately
after delivery. Rapid doses can cause hypotension.
162
Prolonged infusions of oxytocin can
| lead to
hyponatremia, fluid retention, and neurologic dysfunction.
163
In the non-preeclamptic patient, an ergot alkaloid (methylergonovine, Methergine)
is
next line therapy, followed by prostaglandins (Hemabate and
| misoprostol)
164
Severe hypertension may occur if the
pregnant patient is given an alpha adrenergic agonist, such as phenylephrine
and ephedrine, and what other medication?
Severe hypertension may occur in the pregnant patient given an alpha-
adrenergic agonist and an ergot alkaloid, such as methylergonovine or ergonovine.
165
Combining phenylephrine and ephedrine and methergine, Why may this combination produce severe hypertension
Ergot alkaloid activate adrenergic receptors, producing a
peripheral vasoconstriction that is additive with sympathomimetics such
as phenylephrine and ephedrine
166
Intravenous administration of methylergonovine is usually avoided and, if
given, should be administered with great
caution ... why?
Methylergonovine (0.2 mg) may be given intramuscularly to provide an uterotonic effect if oxytocin administration has proven ineffective for uterine atony. Intravenous administration of methylergonovine (in small
divided doses) should be avoided and if given, then administered only with
great caution, because intense vasoconstriction may lead to acute hypertension, seizures, cerebrovascular accident, retinal detachment, and myocardial arrest; this possibility is of special concern in patients with preedampsia or cardiac disease.
167
Describe IV pain control in the postpartum
mother who is breast-feeding her
infant.
Typically, only 1 % to 2% of the maternal dose of appears in breast milk.
The small amount of analgesics found in breast milk are not considered
harmful to the neonate. However, it is advised that the breast-feeding
mother takes medication immediately after breast feeding to minimize the
neonatal dose
168
Obese parturients are at increased risk
for what eight (8) complications? What
fetal risks are associated these maternal
complications?
Eight complications associated with the obese parturient are: ( 1) gestational
hypertension; (2) gestational diabetes; (3) preeclampsia; (4) infection;
(5) thromboembolism; (S) stillbirth; (6) fetal demise; (6) difficult vaginal
delivery; (7) cesarean delivery; and, (S) difficult airway. The fetus is at risk
for macrosomia, shoulder dystocia, and congenital anomalies
169
What is the preferred method of pain
| relief for the obese parturient?
Early placement of continuous neuraxial analgesia is the preferred method
of pain relief for the obese parturient. Neuraxial analgesia provides excellent
pain relief without sedation and provides a conduit for anesthesia
should the patient require a surgical delivery.
170
What three (3) maternal complications
pose the greatest acute risks to the fetus
during non-obstetric surgery during
pregnancy?
Maternal complications involving severe hypoxia, hypotension, and changes
in PaCO2 can all cause feta! asphyxia and pose the greatest acute risk to
the fetus during non-obstetric surgery in the pregnant patient
171
Which two general procedures are associated
with the greatest risk of preterm
labor in non-obstetric surgery during
pregnancy?
Abdominal and pelvic procedures are associated with the greatest incidence
of preterm labor.
172
Intra-abdominal procedures during the third trimester are most likely to be
associated with preterm labor
173
Which trimester is the safest to provide non-obstetric surgery and anesthesia for the parturient?
The 2nd trimester is the safe to provide non-obstetric surgery and anesthesia for the parturient.
174
Highest risk for teratogenicity
1st trimester
175
Highest risk for preterm labor
3rd trimester
176
Describe the use of a paracervical block
| during labor and delivery?
A paracervical block (placed by obstetrician} has fallen out of favor due
to the high incidence of fetal asphyxia, fetal bradycardia, and systemic
anesthesia toxicity. If used, a bilateral paracervical block will effectively
block pain impulses to the cervix and uterus during the first stage oflabor.
It is not effective during the second stage of labor. If a paracervical block is
performed, a dilute local anesthetic and slow administration (waiting 5- 1 O
minutes between injecting each side} can reduce the risk of poor neonatal
outcome
177
What Apgar score signifies mild to
moderate depressed function? And what
noninvasive interventions can be used in
this instance if the HR is above lOO?
Apgar scores of 3-7 signify mild to moderate depressed function. Keep the
neonate warm and dry. Stimulate. Administering 02 by face mask without
positive pressure ventilation can frequently improve the neonates Apgar
scores.
178
List two actions that should be taken if
| the newbom's HR falls below lOO bpm.
lfthe newborn's heart rate falls below lOO bpm, begin positive-pressure
face mask ventilation and Sp02 monitoring
179
What intervention is recommended
when the neonates HR falls below 60
bpm?
When an infant's heart rate falls below 60 bpm, intubate if not already done. Continue positive pressure ventilation, and begin chest compressions
and cardiac monitoring.
180
If a newborn has meconium and blood
below the cords, what are the appropriate
actions?
A conservative approach is taken. Suction and intubate only if the newborn
has a depressed Apgar score with meconium below the cords.
181
Meconiumn stained amniotic fluid (MSAF) aspirated into the lungs can cause ____? how can you suction?
significant respiratory distress. Suctioning can be accomplished via the ETT. The
neonate should be transferred to the NICU.
182
What is an EXIT procedure and what are
| the anesthetic considerations?
EXIT stands for ex utero intrapartum procedure. This procedure involves
surgical correction of a fetus during partial delivery.
183
The EXIT procedure is indicated in instances
where the fetus would not survive surgery after separation from uteroplacental support (e.g., large fetal neck mass, reversal
of tracheal occlusion form dips placed for congenital diaphragmatic hernia
repair)
184
Anesthetic considerations including
| .
maintaining uterine relaxation
during fetal surgery and providing anesthesia for both mother and fetus.Volatile agents and IV narcotics that cross the placenta are used.Usually
2 anesthesia teams are needed, one for the mother and one for the fetus
185
In EXIT procedures, After surgical correction is completed,
the fetus is delivered. Once the cord
is damped, uterotonic agents are administered and inhalation agents are
decreased to minimize maternal blood loss
186
```
A pregnant patient receives a saddle
block and suddenly becomes agitated,
dyspneic and her legs thrash. Shortly
after this, she becomes unconscious and
apneic. Why?
```
Intravascular injection oflocal anesthetic may have occurred. These are
signs and symptoms of seizures
187
```
A pregnant patient receives a saddle
block and suddenly becomes agitated,
dyspneic and unable to move her legs.
She then becomes unconscious and
apneic. Why?
```
High spinal The key here is the motor paralysis, which indicates that the
local anesthetic caused paralysis, which would not be seen with intravascu·
tar injection
188
What should be done once the diagnosis
| of placenta accreta is made?
The anesthetist should be prepared for rapid blood and fluid replacement
prior to surgery. This preparation should include placement of several largebore
intravenous catheters and the immediate availability of blood. Ideally
patients with placenta accreta should be cared for in larger hospitals with
access to a fully stocked blood bank and 24 hour in-house OB/Anesthesia
services.
189
The amniotic sac has ruptured (amniorrhexis) in the parturient and is accompanied by bleeding and fetal heart rate deceleration. What should you suspect? Is this an emergency?
Whenever bleeding occurs with rupture of membranes in the parturient,
particularly when accompanied by fetal heart rate deceleration or fetal bradycardia, vasa previa should be suspected. This is a true obstetric emergency as fetal mortality rates are high. ranging from 5O% to 7S%.
190
Define vasa previa.
Vasa previa is defined as the velamentous insertion of the fetal vessels over
the cervical os (i.e., the fetal vessels traverse the fetal membranes ahead
of the fetal presenting part). Thus, the fetal vessels are not protected by
the placenta nor the umbilical cord. (A velamentous cord insertion occurs
when the umbilical cord inserts into the fetal membranes instead of into
the middle of the placenta.) Rupture of the membranes is often accompanied
by tearing of a fetal vessel, which may lead to exsanguination of the
fetus. Vasa previa occurs rarely, I in 25OO to I in 5OOO deliveries.
191
List five (S) risk factors for vasa previa.
Risk factors for vasa previa are: (I) presence of placenta previa; (2) a
low-lying placenta in the second trimester; (3) placental accessory lobes;
(4) in vitro fertilization; and, (S) multiple gestations
192
Describe the management of vasa
| previa.
Vasa previa is a true obstetric emergency that requires immediate delivery
of the fetus. almost always by the abdominal route and under general anesthesia.
Neonatal resuscitation requires immediate attention to neonatal
volume replacement with colloid, balanced salt solutions, and blood
193
Consider the pregnant patient who is
attempting a trail oflabor {TOLAC)
for vaginal birth after cesarean section
{VBAC): what is a major concern
Uterine rupture causes a rapid exsanguination and is a life-threatening
potential complication that may occur with vaginal birth after cesarean
section (VBAC). The incidence of uterine rupture with VBAC labor is high·
er than once thought, now approaching 2%. Fetal mortality is almost 80%.
194
What are the two (2) leading causes of
| peripartum hemorrhage
The two leading causes of peripartum hemorrhage are ( l) uterine atony,
and (2) placenta accreta.
195
What can be done to reduce the risk of inadvertent intravascular injection of local anesthesia when dosing an epidural catheter?
The use of small divided doses of drug can greatly reduce the risk of a more serious local anesthetic overdoses. Even properly placed catheters can migrate into a vein {or intrathecally) with prolonged use. This possibility should be taken into account before each new administration of drug Epidural doses of lidocaine and chloroprocaine, given intravascularly, will result in seizures.
196
List seven (7) interventions in the treatment of local anesthetic toxicity {LAST) in the obstetric patient undergoing epidural anesthesia
early recognition of the reaction {accomplished by observing the patient and her vital signs and by talking to her); (2) prevention of the progression of the reaction (propofol 20-50 mg will stop seizure activity - use only if hemodynamically stable); (3) maintenance of oxygenation (accomplished by maintaining a patent airway and, if necessary, intubating with succinylcholine and cricoid pressure); (4) support the circulation (accomplished by elevating the legs, displacing the uterus to the left, and rapid administration of intravenous •
fluids if needed); (5) treatment of cardiotoxicity (immediate infusion of
20% lipid emulsion has shown reversal of cardiotoxicity), (6) treatment of
local anesthetic induced arrhythmias (Amiodarone is the drug of choice),
and (7) assess the condition of the fetus as soon as possible after seizures
are observed (prompt maternal resuscitation usually will restore uterine
blood flow and fetal oxygenation
197
What causes fetal acidosis? What problems
| will be seen in the fetus?
Fetal asphyxia leads to rapid decreases in fetal pH. Hypoxia and acidosis
cause a shift to the RIGHT in the fetal oxyhemoglobin dissociation curve.
The fetus will have deceased oxygen delivery, increased systemic vascular
resistance, and depression of the myocardium.
198
What is assessed by a fetal scalp monitor?
| Is this technique still used?
Fetal scalp monitoring involves taking blood samples from the scalp of the
fetus and measuring blood pH. Fetal scalp blood sampling is used to assess
the degree of fetal acidosis for asphyxia when abnormal heart rate patterns
cannot be corrected or their significance is unclear. Fetal scalp monitoring
has largely been replaced by either fetal scalp stimulation or vibroacoustic
stimulation
199
```
While caring for a parturient, concern
arises for the well-being of the fetus.
The FHR tracing is indeterminate. The
obstetrician employs digital stimulation
of the fetal scalp and subsequent FH R
accelerations are seen. What information
does this suggest?
```
FHR accelerations seen after digital scalp stimulation or vibroacoustic
stimulation gives reassurance that fetal acidosis is unlikely
200
```
Name five (S) anatomic or physiologic
changes that can lead to a difficult airway
in the obstetric patient
```
Five anatomic or physiologic changes that can lead to a difficult airway in
the obstetric patient include: ( 1) fluid retention leading to airway edema;
(2) decreased FRC (by 20%) with an increase in 02 consumption (by 60%)
resulting in a more rapid hypoxemia after induction; (3) breast enlargement
impeding laryngoscopy; ( 4) full dentition impeding view; and, ( 5)
need for RSI (rapid sequence induction} which can lead to unanticipated
difficult airway.
201
You are confronted with an unexpected difficult intubation of the pregnant patient. After induction, you are unable to intubate the trachea via multiple
techniques. Mask ventilation remains adequate and there is NO fetal distress. What are your options?
If there is no fetal distress, awaken the patient. Consider awake intubation or regional anesthesia unless contraindicated.
202
```
You are confronted with an unexpected
difficult intubation of the pregnant
patient. After induction, you are unable
to intubate the trachea via multiple techniques.
Mask ventilation is adequate,
but fetal distress is present. What are
your options?
```
Continue anesthesia by mask ventilation while an assistant maintains cricoid
pressure. Provide halothane or sevoflurane with spontaneous ventilation
if possible. Attempt placement of LMA and if possible attempt to pass
the ETT via the LMA. If the airway becomes inadequate, invasive airway
techniques may be required to support the parturient during delivery of
the fetus in distress.
203
You are confronted with an unexpected
difficult intubation of the pregnant
patient. You were unable to intubate the
trachea and mask ventilation is inadequate. What are four rescue options for this situation?
For the parturient who cannot be intubated or ventilated by mask there are
four rescue options: (l) insertion of an esophageal-tracheal Combitube,
(2) use of the laryngeal mask airway (LMA) with cricoid pressure, (3)
transtracheal jet ventilation (TTJV}. and (4) emergent cricothyrotomy or
tracheostomy.
204
```
List five (5) specific actions in treating
amniotic fluid embolism.
```
Treatment of amniotic fluid embolism consists of aggressive cardiopulmonary
resuscitation, stabilization and supportive care.
(l) Intubate and ventilate with 100% 02
(2) begin cardiopulmonary resuscitation if there is no pulse,
(3)insert two large bore intravenous lines, an arterial line, a bladder catheter,
and consider pulmonary artery catheter placement,
(4) monitor Sa02, EKG, pulmonary and systemic blood pressures, cardiac indices, and neurologic function, and
(5) notify the blood bank for probable need of fresh frozen plasma and platelets. Delivery of the fetus and the placenta as soon as feasibleimproves maternal and fetal outcome
205
The pregnant patient with mitral stenosis
develops hemodynamically unstable
atrial fibrillation during labor and delivery.
What is your course of action
The patient should be treated immediately. Synchronized cardioversion isthe first choice for treating acute life-threatening atrial fibrillation. Cardioversion
can be performed safely throughout pregnancy without adverse
effect to the fetus.
206
```
Your patient has aortic stenosis and is
being prepared for an emergent cesarean
section. The patient has not been
adequately hydrated and hypotension
is a major concern - which anesthetic
technique will you use?
```
General anesthesia is the gold standard in severe or symptomatic aortic stenosis.
Although regional and neuraxial techniques are still viable options,
hypotension is more common with these techniques, compared to general
anesthesia. Hypotension is most common with a spinal anesthetic, less
common with epidural anesthetics, and modestly less common with a regional
technique; a general anesthetic is associated with the least likelihood
ofhypotension and adequate maintenance of SVR.
207
The patient has a prolonged labor and
difficult vaginal delivery. At the end of
the case the patient is unable to dorsiflex
the foot, what nerve was most likely
injured?
The common peroneal nerve. This nerve can be compressed between the
head of the fibula and a lithotomy stirrup when the patient is in the lithotomy
position, or from prolonged squatting. Foot drop (inability to dorsiflex
the foot) results.
208
What is the metabolic syndrome? What
is the prevalence of metabolic syndrome
in the U.S. population?
The metabolic syndrome, also known as syndrome X and insulin resistance
syndrome, is a cluster of metabolic abnormalities associated with an
increased risk of diabetes and cardio·vascular events. Individuals with this
syndrome have up to a fivefold greater risk of develop-ing type 2 diabetes
mellitus (if not already present) and are also twice as likely to die from a
myocardial infarction or stroke compared with those without the syndrome.
Individuals with metabolic syndrome also have prointlammatory
and prothrombotic states. There is a 3S% to 40% prevalence of metabolic
syndrome in the U.S. population
209
```
The American Heart Association and the
National Heart, Lung, and Blood Institute
define metabolic syndrome as the
presence of three or more of 5 criteria.
State the 5 criteria that
define metabolic syndrome
```
Metabolic syndrome is defined by the presence of three or more of the following
5 criteria:
(l) central obesity (increased waist circumference):> 102 cm (40") in males, >88 cm (35") in females;
(2) dyslipidemia: triglycerides
~150 mg/dL;
(3) dyslipidemia: HDL s;40 mg/dL in males, HDL s;50 mg/dL in females;
(4) hypertension: ~130/85 mm-Hg or use of antihyper-tensives;
(5) elevated fasting glucose: ~100 mg/dL (~5.6 mmol/L) or use of a medication for hyperglycemia.
