Section 4: Anesthesia for surgical procedures .. Flashcards
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.
(l) smallest possible incision;
(2) less surgical stress;
(3) less pain; •
(4) faster recovery;
(5) shorter hospital stays; and,
(6) improved overall satisfaction.
State six {6) advantages of robot-assisted
surgery from the surgeon’s perspective
(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).
Although robot-assisted surgery affords
many advantages to the patient and
surgeon, there are major anesthetic management considerations and
challenges. Positioning
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. .
Difficulties inherent in patients having
prolonged surgery in Trendelenburg position are present: i
Increased mean arterial pressure in brain, increased cerebral blood volume, decreased cardiac output and perfusion to lower extremities, and decreased perfusion to vital organs. (
ROBOTIC , There is potential common , nerve injury
peroneal nerve damage due to lithotomy position
ROBOTIC Urine output
may be decreased and generally responds to fluid challenge.
(5) Difficulties with peritoneal insufflation are present:
decreased compliance, increased airway pressure, increased ventilation-
perfusion mismatch, and hypercapnia. (6)
PNEUMOPERITONEUM: Blood pressure reduction may be necessary secondary to resultant
increase in systemic vascular resistance because of the pneumoperitoneum.
Describe the obturator reflex.
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
TURBT differs from TURP in that the
surgical resection is not necessarily carried out in the midline.
List two anesthetic techniques to abolish
the obturator reflex during transure·
thral resection of the bladder tumors
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).
TURBT procedures are more commonly performed with (
1) general anesthesia and neuromuscular blockage or (2) neuraxia/ anesthesia to T9-TIO providing adequate anesthesia and preventing the obturator reflex
Neuraxial anesthesia to prevent the obturator reflex
T9-T10
What are four (4) goals of adding hyal·
uronidase to peribulbar local anesthetic
blocks?
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
What is a major dilemma in the patient
with an open eye-full stomach?
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.
Describe the plan for induction in an
open eye-full stomach patient. Is succinylcholine contraindicated?
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
Raise IOP to a much greater degree than succinylcholine,
including crying, Valsalva maneuver, forceful blinking, rubbing eyes, and
coughing or bucking.
What volume of air (ml) will fill the
tracheal and bronchial cuffs of a double-
lumen tube?
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.
The bronchial cuff is checked with a
3 mL syringe but rarely will the bronchial cuff require greater than 2 mL to createan adequate seal_
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?
Bright blue, low-volume, low-pressure endobronchial cuffs are incorporated
on the double-lumen tube for easier visibility during fiberoptic bronchoscopy.
Flexible fiberoptic bronchoscopy is
essential to
placement of a double-lumen tube (DLT)
What is the location of the blue endobronchial cuff when a left-sided double- lumen tube is properly placed?
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.
Identify the two (2) major perioperative goals for the patient with Graves’disease.
The most important preoperative goal for the patient with Graves’ disease is to make the patient euthyroid before surgery
Grave’s disease: The other major perioperative goal is to
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.
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.
ECT play an important role in managing 3 things
Mania , depression, affective disorders
During ECT, the electrical stimuluar produces a
Grand mal seizure consisting of a brief TONIC phase followed by a more prolonged CLONIC phase.
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.
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
Initial parasympathetic effect of ECT are
Salivation, transient bradycardia, asystole
Define “hypertensive crisis” (hint: think
arterial blood pressure measurements)
Hypertensive crisis is defined as arterial blood pressure ~180/120 mm-Hg
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.
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.
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.
Other treatment alternatives for HTN emergency are
nicardipine, fenoldopam, esmolol, and labetalol
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.
A third-generation dihydropyridine calcium channel blocker with ultrashort duration of action and selective arteriolar vasodilating properties
Clevidipine
What is the leading cause of postoperative
hospital admission?
Inadequate pain relief is the # 1 cause of postoperative hospital admission.
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.
What commonly used anesthetics agents
have a favorable influence on bronchomotor tone?
Isoflurane, sevoflurane, propofol, ketamine, and midazolam all possess
bronchoprotective properties
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
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.
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.
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
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.
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.
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
Clear liquids,
2 hours
Breast milk,
4 hours
Infant formula,
6 hours
Fried or fatty meals,
8 hours or more.
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.
Diuretics should not be used to treat
pulmonary edema unless hypervolemia present.
Pulmonary aspiration, Antibiotics (only indicated if
fever longer than 48 hours or increased WBC greater than 48 hours.)
Pulmonary aspiration: Steroids are of
questionable benefit {prolonged hospital stay).
As the population ages and remains
physically active through their sixth
decade, major orthopedic joint replacement procedures
are increasingly more common.
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
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.
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
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
Treat HoTN in BCIS with
A-agonists
It has been suggested that cardiovascular collapse in the context of BCIS be treated as what?
right-sided heart failure
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
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
TRAUMA patient: If the patient’s blood type is known,
administer type-specific whole blood or packed red blood cells (PRBCs).
TRAUMA patient If the patient’s blood type is not known,
administer 0 -negative packed red blood
cells (PRBCs)
TRAUMA fluid resuscitation advise a fixed ratio
(1 :1:1) of PRBCs, fresh-frozen plasma
(FFP). and platelets to approximate whole blood
TRAUMA fluid resuscitation advise a fixed ratio
(1 :1:1) of PRBCs, fresh-frozen plasma
(FFP). and platelets to approximate whole blood
TRAUMA resuscitation avoid
Avoid hydroxyeth· yl starch solutions (e.g. Hespan). which are associated with increased rates of renal replacement therapy and adverse events.
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.
Is essential in the early care of the burned patient
Fluid resuscitation
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.
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
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
Burn fluid resuscitation emphasizes
crystalloids, particularly lactated Ringers
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
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.
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.
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
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
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.
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}
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.
