Mars Brimhall, SRNA - Midwestern
Mars Brimhall
• Bachelors in Biology and Chemistry
at Northern Arizona University.
• Nursing degree from Northern
Pioneer College.
• Nursing experience in the ER, ICU,
and CV/ICU settings.
• Currently a Student Registered
Nurse Anesthetist (SRNA) @
Midwestern University, Glendale –
AZ.
• And Yes, I love space jokes …
What is it?
(Afib)
• Occurs because of multiple
reentry circuits in the atria.
• The atria are depolarized at a
rate of 400 to 600 beats/min.
• These rapid impulses cause the
muscle of the atria to quiver
(fibrillate).
• Results in ineffectual atrial
contraction, a subsequent
decrease in cardiac output,
and a loss of atrial kick.
Yes, My parents were Hippies.
If > 100 beats/min
then termed RVR or
“uncontrolled”.
Signs & Symptoms
• Results in ineffectual atrial
contraction, a subsequent
decrease in cardiac output, and
a loss of atrial kick.
• Patients may develop intra-atrial
emboli from stagnate atrial
blood.
• May produce signs & symptoms
that include: lightheadness,
palpitations, dyspnea, chest
pressure/pain, and hypotension.
• If stable and RVR, treatment is first
directed toward controlling the
ventricular response, rather than
converting the dysrhythmia to a sinus
rhythm.
• If cardiac function is normal – Calcium
channel blockers or Beta blockers
• If cardiac function is impaired – Digoxin,
Diltiazem, or Amiodarone.
• If severely symptomatic synchronized
cardioversion may be considered.
I have a sister. No, her name is not Venus.
Meet Marvin
We will call him Marvin
(Name changed to
protect the incent –
really for HIPPA)
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73 year old Male patient
NKDA
Weight: 106 kg
Height: 185 cm
BSI: ~31
Today’s Surgery
• Presenting for:
• Left Total Hip Replacement
secondary to Osteoarthritis.
I had two dogs as a kid – Phobos and Deimos.
• 15 pack year history –
Stopped smoking 40 years
ago.
• Gastric reflux
• Hiatal hernia
• Back pain
• Arthritis
• Hypertension (HTN)
• Depression
• Right total hip replacement in
2008.
• EKG showed NSR.
• CXR had possible paramedian mass or
cardiac enlargement.
• CT obtained, “No mass detected, no
significant abnormality.”
• Cardiac clearance stated: “Low-risk for
cardiovascular complications. No CV
symptoms & minimal risk factors. No
MI.”
• All Lab studies were within normal
limits.
• Current medications:
• Saw palmetto, calcium, multivitamin,
esomeprazole 40mg AM, and fluoxetine
20mg AM.
• A slightly obese elderly gentleman.
• Lungs were clear to auscultation
• No cardiac murmur or rub was
noted. RRR.
• Pre-operative vital signs:
• BP 124/82
• HR 80
• RR 18
• SaO2 88% room air
• 94% 2L Nasal Cannula
• T 36.9
• MP II, TMD > 7cm, Positive ULB test,
Full ROM.
Do you know why Phobos and Deimos?
• All Standard monitors were attached
• Patient was preoxygenated for 5
minutes.
• Before induction 2 grams of Ancef IV
were administered.
• Due to the patient’s history of reflux a
standard general anesthesia with a
rapid sequence induction (RSI) was
preformed.
• For induction:
•
•
•
•
50 mcg Fentanyl
60 mg Lidocaine
160 mg Propofol and
100 mg succinylcholine IV were
administered.
• After loss of eyelid reflex and
fasciculations observed direct
laryngoscopy was preformed
• Mac #3 blade used.
• Cormack Grade I visualization.
• Easy atraumatic intubation.
• Cords remained open after
intubation.
• Endotracheal tube placement
was confirmed by positive, equal
bilateral breath sounds and
positive end-tidal CO2 tracings
for 3 consecutive breaths.
• Sevoflurane was titrated to
1.8%.
• The patient was observed to
become tachycardiac.
• A rate in the upper 130’s and an
irregularly irregular rhythm.
• Immediate hypotension was also
noted.
• 100 mcg of phenylephrine 5x.
• Hypotension was moderately improved
but still sub-baseline levels.
• A 12-lead EKG was obtained
that showed new-onset atrial
fibrillation with rapid ventricular
response
FYI - Phobos and Deimos are the moons of Mars.
• The surgery was cancelled and the
choice was made to emerge patient
immediately from anesthesia.
• A smooth atraumatic emergence and
extubation took place.
• No conversion of cardiac rhythm.
• However, Patient now normotensive.
• The patient transferred to PACU.
• Still in A-fib with RVR.
• A cardiac consult was requested and
echocardiogram ordered.
How Often?
• New on-set atrial fibrillation (AF) is not
uncommon during or after surgery. It may
present for the first time during anesthesia
and surgery.
• AF is the most common sustained cardiac
dysrhythmia.
• The incidence of AF approximately doubles
with each decade of adult life.
• New onset AF occurs most after:
• Cardiac surgery (10-65%)
• Followed next by thoracic surgery (1023%)
• Then non-thoracic surgery (5-10%)
• The waves from this active vary in size,
shape, and timing and this chaotic behavior
leads to erratic ventricular contractions that
can be greater than 100 beats per minute
or rapid, as in this case.
• The overall mechanisms for AF is
not completely understood and
are most likely are multifactorial.
• Some of the mechanisms that
have been thought to be
involved with AF are:
Mechanisms?
• fibrotic areas in the atrium
• Inflammation
• over-production of catecholamines
or increased susceptibility to them.
• autonomic imbalance
• electrolyte imbalances and fluid
changes.
If a meteorite hits the earth what do you call the ones that
miss?
• The literature suggests AF has several risk
factors related to its occurrence.
• The main risk factors include:
• age (> 60yr)
• higher preoperative heart rate( >74
beats/min)
• male gender
• Hypertension
• higher body mass index
• left atrial enlargement
• vascular surgery
• pervious history of atrial fibrillation
• emergency operations
• a history of congestive heart failure
• use of intraoperative transfusion
• renal failure
• chronic obstructive pulmonary disease.
• The literature also revealed that AF is
linked to:
• Increased mortality and morbidity
• Increased cost of stay and length of stay.
• Higher ICU admissions.
Complications
• The risk of death after new onset AF in
critically ill patients after non-cardiac
surgery is 2- to 6-fold higher.
• Patients that developed Atrial fibrillation
have:
• a higher incidence of postoperative pneumonia
and acute respiratory failure
• greater hospital stay
• 30-day mortality.
• One of the most important anesthesia
implications of AF is the loss of the
atrial contribution to ventricular filling,
or “Atrial kick”.
• may result in a decrease stroke volume of
up to 20 – 30 %.
• This change in cardiac stroke volume can
lead to hemodynamic instability,
myocardial ischemia, and hypoxia.
• Long term implications could be
thromboembolic events or strokes due
to the formation of thrombi in the atria
due to stasis of blood and the
development of atrial and/or
ventricular Cardiomyopathy.
metiowrongs.
• Treatment of AF is indicated if the
patient is symptomatic,
hemodynamically unstable ,and if
they develop cardiac ischemia or
heart failure.
• Treatment is to restore and sustain
normal sinus rhythm, prevent
thromboembolic events, and control
ventricular rate.
• This is achieved by use of
antiarrhythmic drug therapy,
anticoagulation therapy,
cardioversion, pacemaker
implantation and/or surgical
procedures, like the Maze
procedure.
• A three-part approach should be taken by
the anesthesia provider.
• The provider should assess the need for, the
proper timing of, and the appropriate way to
restore a sinus rhythm.
• The provider should take steps to guarantee
appropriate control of the ventricular rate
while the patient is in atrial fibrillation.
• Thought should also be given to the need for
anticoagulation to prevent embolic stroke.
• If the patient is non-symptomatic and
hemodynamically stable sometimes no
intervention is needed as up to two thirds of
patients will spontaneous convert to a sinus
rhythm in a 24 hour timeframe.
• In this case report new onset AF was witnessed
with induction of anesthesia. It was decided the
best plan of action was to cancel surgery and
emerge the patient from anesthesia.
• This was chosen to determine if the hypotension
the patient was experiencing was due to the
anesthetic or loss of stroke volume due to loss of
atrial systole.
• After anesthesia was ended the patient was
hemodynamically stable but still remained in AF
with RVR.
• Immediate cardioversion was not indicted
because for being non-symptomatic.
• The attending anesthesiologist also had concerns
if the patient had previous atrial fibrillation
periods that had spontaneously converted to sinus
rhythm.
• Cardiac consult, full electrolyte panel, and
echocardiogram were ordered immediately upon
arrival in the anesthesia recovery area.
• AF occurred even in a “cardiac
cleared” patient. This patient
presented with three of the most
common risk factors for AF.
• Age > 64
• Male gender
• History of systemic hypertension.
• Although rare, AF can happen in any
surgical patient and the incidence
increases with age.
• In this case study, AF was quickly
recognized during induction of
anesthesia and appropriate steps
were taking to ensure the best
treatment and patient outcome as
possible.
Any Questions?
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