Perioperative Screening for Obstructive Sleep Apnea Patient Safety

Marietta Bellamy Bibbs, BA, RPSGT
Morton Plant Mease Healthcare
Clearwater, FL
Discuss the importance of recognizing undiagnosed
obstructive sleep apnea (OSA)
Review the patients at risk for OSA
Describe the consequences of untreated OSA in the
surgery patient
Review screening tools to identify at risk patients
Discuss preventative measures to decrease
perioperative risk in OSA patients
Undiagnosed OSA
Statistics
Consequences of
Untreated OSA
Identifying the
At-Risk Patient
The Surgical
Patient
Post-operative
catastrophes
Screening Tools
and Preventive
Measures
Men with Moderate OSA
Women with Moderate OSA
Obese Men
Obese Women
Risks of Untreated OSA
Risk of Dying
Percent
Undiagnosed
Population
Percentage
Clinical Signs and Symptoms
BMI 35 kg/m2
Pediatric patients
95th
Hypertension (difficult to manage and treat)
percentile for age and gender
Large Neck (>17 inches in men and >16 inches in
women
Craniofacial abnormalities
Tonsils nearly touching or touching in the
midline
History of Airway Obstruction During Sleep
Anatomical Nasal Obstruction
Frequent and Loud Snoring
Awakens with choking sensation from sleep
Frequent arousals from sleep
Pauses in breathing during sleep
Restless sleep, difficulty breathing or increased
respiratory effort during sleep
Excessive Sleepiness
Excessive sleepiness or fatigue despite adequate sleep
Falls asleep easily in sedentary (non-stimulating) situations
Parent or teacher notes child is sleepy during day, easily distracted and overly aggressive and difficulty concentrating
Child is difficult to arouse at usual awakening time
In the undiagnosed Obstructive Sleep Apnea (OSA)
patient population…..
Minimize the number of undiagnosed patients
presenting for surgery.
Provide appropriate monitoring and access to postoperative evaluation.
Provide longitudinal care if indicated.
Continue post-operative PAP therapy since treatment
requirements may increase.
It is estimated that 82% of men and 92% of
women with moderate-severe OSA have not
been diagnosed
40% of obese men and 50% of obese women
have been identified as having OSA
Estimated life span of untreated OSA is 58 years
(normal men 78 yrs., women 83 years)
John Hopkins study found severe OSA increased
risk of dying by 46%
18 -20 million adults suffer from symptomatic OSA or
severe asymptomatic OSA
It is estimated that 90% of those suffering from OSA
are still undiagnosed and untreated
4% of the US population affected
Frequently goes unrecognized and undiagnosed in
the medical community
Affects all aspects of life
OSA patients have a higher risk of post-operative
complications
Associated with increased sick days and loss of
productivity at work
Prescription costs:
OSA patients with hypertension receive more antihypertensive prescriptions and other drug
therapies that are higher in cost
Highest diagnosis-specific expenditures related to
hypertension and cardiovascular disease
A Canadian study on a targeted group of OSA
patients revealed that they:
used 25-50% more medical resources in the 5 years
prior to diagnosis
had more physician office visits
spent more nights in the hospital
Had higher physician costs than matched controls
Obesity
Enlarged adenoids, tonsils, and soft palate
tissues including large uvula, low lying soft
palate and excessive pharyngeal tissue
Jaw malformations
Large tongue
Snoring
Waking up from snoring
Witnessed apnea
Frequent nocturnal
awakenings
Sleep maintenance
insomnia
Waking unrefreshed in
the mornings or
following naps
Commonly Recognized
Symptoms
Waking up choking,
short of breath or
gasping for breath
Excessive daytime
sleepiness
Chronic fatigue/tiredness
Falling asleep or nodding
off at inappropriate
times
Unrecognized
Symptoms
Nighttime sweating
Nighttime GE reflux
Automatic behaviors
Sleep drunkenness
These symptoms are often not thought of or
recognized as being associated with OSA in the
medical community:
Change in personality or mood
Weight gain
Nocturia
Morning headaches
Morning dry mouth
Loss of libido or impotency
Poor concentration
Decreased memory, especially short term
Studies have documented that 80% of men and
90% of women have obstructive sleep apnea
and have never been diagnosed.
Undiagnosed OSA presents special challenges
for patients and healthcare workers, particularly
in surgical patients
OSA patients are at high risk for surgical
complications
Hypertension
Untreated OSA is associated with
hypertension in 40 % of patients
30 % of patients with idiopathic
hypertension have OSAS
Cardiac arrhythmias during sleep
Sinus arrhythmia, sinus
bradycardia, atrial fibrillation,
asystole, second-degree AV block,
PVCs, and VT
Heart attacks
Stroke
Type 2 Diabetes Mellitus
Related to comorbities
Congestive Heart Failure
Myocardial Infarction
Arrhythmias
Sudden Cardiac
Event-related sleep disturbance
Decreased arousal threshold related to sleep
fragmentation
Decreased arousal delay due to narcotics
OSA patients have a higher rate of
Difficult Intubation
Difficult Extubation
Hypercapnia
Oxygen desaturations
Cardiac insults
American Society of
Anesthesiology
published guidelines
recommending that
patients should be
screened for OSA
before surgery.
Goal:
Identify patients undiagnosed
OSA patients prior to surgery.
Diagnose and treat prior to
surgery when possible.
If unable to diagnose prior to
surgery, treat patients as if
they have documented OSA in
order to avoid complications.
How do you screen patients pre-operatively?
What do you do with patients who screen positive?
How are these patients monitored?
How and when are patients treated that screen positive?
What happens after discharge?
Patient Focused Approach
Emphasis on communication about effects of untreated OSA
A smooth, streamlined experience for patients
Consistent, respectful care and improved surgical outcomes
Education about OSA during the initial preoperative process
Increased level of patient safety and trust in our services
Focused monitoring, preparedness and intervention
Eliminate or markedly reduce the
unrecognized OSA patient presenting for
surgery
Create heightened awareness of which
patients may be at increased
postoperative risk
Provide opportunity to identify and
intervene with patients who are noncompliant or inadequately treated
OSA patients will present for surgery in one of
three categories:
1. Known OSA and compliant with therapy
2. Known OSA :
Mild OSA and therapy not recommended
Refused therapy or non-compliant
Other therapy, e.g., weight loss, surgical intervention,
dental appliances
3. Status unknown
Patients with known OSA and on no active therapy:
May be asymptomatic or minimally symptomatic
May become symptomatic post-op
Patients who are non-compliant and unrecognized:
These patients should be the primary focus of a
perioperative sleep apnea safety program
Screening tools assist with identifying patients
at highest risk for OSA using established risk
factors.
Obesity and increasing age are strong risk
factors for OSA.
Common signs and symptoms include loud
snoring, observed apnea, daytime
hypersomnolence, urinary frequency at night
and morning headaches.
Male sex, excessive alcohol intake, and female
menopause.
Craniofacial abnormalities, such as retrognathia
and macroglossia.
Wide neck circumference (17 inches for men
and 16 inches for women), are also considered
as risk factors for OSA.
Surgeons/anesthesiologists may not be
informed of sleep study results (clinical
diagnosis of OSA noted by record review).
One study indicated:
86% of patients were not identified by surgeons.
47% of OSA patients were not identified by
Anesthesiologists.
OSA is a major risk factor for perioperative adverse events;
however, no screening tool for OSA has been validated
specifically in surgical patients.
If you think someone might have sleep apnea, you might not be
correct. You cannot always pick out OSA patients by looking at
them.
The American Society of Anesthesiologists screening guidelines
recommend that OSA screening should be done on every
patient.
Factors in OSA that could increase perioperative
complications:
Anatomical imbalance
Lung volume reduction (decreased FRC and ERV)
Sympathetic nervous system activation
Ventilatory instability
Impact of sedatives, anesthetics and analgesics
on respiratory function:
Dose dependent depression of upper airway
muscles.
Depression of central respiratory output and upper
airway reflexes (increased collapsibility of the upper
airway).
Increased collapsibility of the upper airway.
Direct action (peripheral) on hypoglossal and
phrenic nerves (phrenic nerve depression leads to
decrease in lung volume).
Case #1:
A 40-year old male with history of mobid obesity and prior
laparoscopic cholecystectomy and nephrolithiasis presented to
the hospital for an incisional hernia repair. He was noted to
have a “difficult airway” preoperatively, but was intubated with
a glide scope without difficulty and was ventilated fairly easily
through surgery.
Postoperatively the patient was extubated and it was noted that
he would drop his oxygen saturation down into the 40% or less
range, even with nasal and high-flow mask O2. His baseline
oxygen range was 80% or less when awake. The patient was
reportedly aware of a diagnosis of obstructive sleep apnea, but
never pursued treatment.
The Anesthesiologist became concerned about
releasing the patient home with witnessed
severe O2 desats.
This resulted in the patient being admitted to
the ICU with plans to titrate him on the Vision
BiPAP.
Pulmonary consult was ordered with resulting
impression that the patient had severe
obstructive sleep apnea
Patient was immediately placed on empirical BiPAP
settings in the ICU at pressures of 12/4 cmH2O
(IPAP/EPAP). The consulting Pulmonologist scheduled
an emergency sleep study on the patient which was
performed the next day as a split-night procedure.
The diagnostic portion of the sleep study confirmed
sleep apnea with AHI of 115 events per hour, SpO2
nadir of 51% and average SpO2 of 69% in absence of
REM or slow wave sleep.
Severe snoring and oxygen desaturations with a
pathological short sleep latency and abnormal sleep
architecture also noted.
The patient failed CPAP and was changed to BPAP
with significant improvement but not significant
resolution of his sleep apnea.
Best response at pressures of 24/18 cmH2O.
Patient was sent home on Auto BPAP with 6
l/minute of O2 bleed-in with overnight oximetry
and a follow-up download of his BPAP machine
to follow response to treatment.
The Berlin
Questionnaire
33% -High Risk
The ASA
Checklist
27% high risk
The STOP and
STOP-BANG
Questionnaire
The Sleep
Apnea Clinical
Score (SACS)
28% high risk
No significant difference in the questionnaires’ ability to identify patients with OSA)
The Berlin Questionnaire was initially used
and validated for outpatient screening of OSA
in primary care clinics but has also been
validated as a screening tool in the surgical
population.
10 questions
5 on snoring
3 on EDS
One on witnessed apnea
One on hypertension
Includes age, gender, weight, height, neck
circumference
Category 1
6 questions on snoring and apnea
Category positive if score 2 or more
points
Category 2
3 questions on tiredness and fatigue
Category positive if score two or
more points
Category 3
positive if HTN or BMI > 30 kg/m2
Question 9 has second part
on frequency of nodding off
or falling asleep driving and is
noted separately.
High Risk
2 or more categories
positive
Low Risk
0-1 categories positive
Sensitivity – 0.89
Specificity – 0.71
Netzer NC et al. Ann Internal Med 1999; 131:485491
• In 2006, the American Society of Anesthesiologists
published obstructive sleep apnea guidelines for
anesthesiologists.
• The ASA recommends that anesthesiologists screen for
obstructive sleep apnea utilizing the ASA checklist of
14 questions (12 for adults and 14 for children).
• The ASA OSA scoring checklist combines the severity of
OSA, invasiveness of surgery and anesthesia, and
postoperative opioid requirements to estimate overall
perioperative risk.
• Not always practical to use in a busy preoperative
practice--too many questions.
Sensitivity
5-14/hr AHI – 72.1
15-30/hr AHI – 78.6
>30/hr AHI – 87.2
Chung F, et al. Anesthesiology 2008; 108: 822-830
• The STOP
questionnaire is a
concise and easy-touse more practical
screening tool for
OSA. It has been
developed and
validated in surgical
patients at
preoperative clinics.
•Four questions combined
with body mass index, age,
neck size, and gender.
•A high sensitivity,
especially for patients with
moderate to severe OSA.
•Two positive questions on
the STOP indicates that the
patient may be at high risk
for OSA.
Snoring
Tiredness
Observed apnea
High blood pressure
High risk is yes to 2 or
more
Low risk is yes to < 2
Sensitivity
5-14/hr AHI – 65.6
15-30/hr AHI – 74.3
>30/hr – 79.3
Chung F, et al. Anesthesiology 2008; 108: 822-830
S = Snoring. Do you snore loudly (louder than talking or loud
enough to be heard through closed doors)?
T = Tiredness. Do you often feel tired, fatigued, or sleepy during
daytime?
O = Observed apnea. Has anyone observed you stop breathing
during your sleep?
P = Pressure. Do you have or are you being treated for high BP?
B = BMI > 35 kg/m2
A = Age > 50 y
N = Neck circumference > 40 cm
G = Male gender
High risk of OSA: ≥ 3 or more questions answered yes
Low risk of OSA: < 3 questions answered yes
High risk greater or equal to 3
Sensitivity
5-14/hr AHI – 83.6
15-30/hr AHI – 92.9
>30/hr AHI - 100
Chung F, et al. Anesthesiology 2008; 108: 822-830
Perioperative
Screening
(Identification)
Monitoring
(keeping the
patient safe)
Discharge
(longitudinal
evaluation and
care)
OSA focused
history and
physical
examination
Perioperative
Screening tool
(STOP-BANG,
Berlin or ASA)
Low Risk for OSA
Proceed with
surgery utilizing
usual perioperative
care
High Risk for OSA
Identify Patient
with wrist alert
band
Patient with
diagnosed OSA
Consider using regional anesthetic or peripheral nerve block with minimal
sedation
Be prepared for difficult airway
management
Consider PAP therapy and inclined
head position to improve FRC
Use short-acting anesthetic, opioid or sedative medications
Consider invasive monitoring for respiratory management
Extubate trachea after patient is completely awake
Ensure Neuromuscular blocking agents are reversed
Focused attention to oxygen saturation and hemodynamics in recovery
Maintain head up at 30-degree position for a minimum of two hours
Maintain lateral position for a minimum of two hours
Use non-opioid analgesics, opioid adjuncts and regional anesthesia
Utilize PAP therapy early to prevent desaturations
Ensure patient is monitored on an appropriate medical-surgical floor
Continuous oxygen saturation monitoring is recommended
Known diagnosis of OSA and compliant on PAP therapy pre-operatively
Continue PAP therapy on the floor
High Risk of OSA or known OSA and non-compliant pre-operatively or known
OSA but PAP pressures unknown
Place patient on auto-PAP therapy
Follow-up with sleep specialist
Diagnostic PSG for definitive diagnosis and treatment
PAP titration if indicated
PAP management and compliance
Date:
Re: Patient: _____________________________
Dear Dr. ___________________:
As a part of pre-anesthesia assessment prior to surgery, your patient was screened
for obstructive sleep apnea using the Stop-Bang Questionnaire*. The results
identified your patient as at-risk for obstructive sleep apnea. Patients identified as atrisk may require further evaluation and follow up for sleep apnea.
Sincerely yours,
____________, MD, DABSM
Medical Director
Sleep Disorders Center
*Frances Chung, F.R.C.P.C., Balaji Yegneswaran, M.B.B.S., Pu Liao, M.D., Sharon A. Chung, Ph.D, Santhira Vairavanathan, M.B.B.S, Sazzadul
Islam, M.Sc., Ali Khajehdehi, M.D., Colin M. Shapiro, F.R.C.P.C., Adapted from: STOP Questionnaire -- A Tool to Screen Patients for
Obstructive Sleep Apnea. Anesthesiology 2008; 108:812–21 Copyright © 2008, the American Society of Anesthesiologists, Inc. Lippincott
Williams & Wilkins, Inc.1
PAT Scripting for Nurses:
The Questionnaire you completed is part of a program to
screen for patients who may have undiagnosed obstructive
sleep apnea. The results indicated that you have a
likelihood of having obstructive sleep apnea. Because of
these results, we would like to include you in the program
for follow-up with your primary care physician for further
evaluation. This means that your physician will be sent a
letter indicating the results, and we will include your name
in the pilot program for evaluation and follow-up. Would
you like for us to include you in the pilot program for
obstructive sleep apnea follow-up?
Date:
Re: Patient: _____________________________
Dear Dr. ___________________:
During pre-anesthesia assessment, your patient was identified as at-risk for
obstructive sleep apnea. The validated assessment tool (The STOPBang1
questionnaire1) revealed a score of ____, indicating a ____fold risk of
obstructive sleep apnea. Patients identified as at-risk indicate the need to be
further evaluated for sleep apnea.
Sincerely yours,
1Frances
Chung, F.R.C.P.C., Balaji Yegneswaran, M.B.B.S., Pu Liao, M.D., Sharon A. Chung, Ph.D, Santhira Vairavanathan, M.B.B.S, Sazzadul
Islam, M.Sc., Ali Khajehdehi, M.D., Colin M. Shapiro, F.R.C.P.C., Adapted from: STOP Questionnaire -- A Tool to Screen Patients for Obstructive
Sleep Apnea. Anesthesiology 2008; 108:812–21 Copyright © 2008, the American Society of Anesthesiologists, Inc. Lippincott Williams &
Wilkins, Inc.1
The Stop Bang—How to Make It Work
Use Other Programs as examples
Use OSA Near Misses as a Teaching Tool
Present SAMBA Patient Selection Guidelines
Identify the Challenges in Implementing a
Perioperative Protocol
The Joint Commission – Sentinel Event Alert
Handouts for patients: Preparing for an
Operation When You Have Sleep apnea