Transcript OSA & the Perioperative Orthopaedic Patient

OSA & the Perioperative
Orthopaedic Patient
Who Has OSA?
OSA
 Underdiagnosed
 OSA is linked to increased risk for HTN, C-V events
including nocturnal arrhythmias, including afib & V-tach,
MI, stroke, & DM.
 Considered an independent risk factor for increased
postoperative morbidity.
 Those with OSA frequently have multiple comorbidities: COPD, HTN, DM, CAD, obesity.
OSA & Obesity
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Attributed to a concommittant rise in prevalence of
obesity. A 10% increase in body weight can increase
your risk of OSA by 6 fold.
Caused by fat deposits around your upper airway and
decreased chest excursion from abdominal obesity.
In one study Obesity is 5X more prevalent among the
those with OSA (Memtsoudis et al).
http://youtu.be/A9lLSw9Rtjs
OSA
 OSA is a partial or complete airway obstruction resulting
in repetitive incomplete or complete cessation of airflow
during sleep a/w strenuous breathing against resistance
followed by period of desaturation, hypercarbia and then
subsequent arousal.
OSA Video
http://www.mayoclinic.org/diseases-conditions/sleepapnea/multimedia/obstructive-sleep-apnea/vid-20084717 - 31k
• OSA Can provoke long term C-V consequences such
as right ventricular dysfunction, atrial fibrillation, heart
failure and stroke.
• OSA can also cause a higher incidence of
complications in the perioperative period including:
post op delirium
hypoxia
aspiration pneumonia
ARDS
PE
Intubation/mechanical ventilation and increased use
of ICU’s
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Diagnosis
Timely diagnosis is difficult
While PSG remains the gold standard for diagnosis, it requires an
overnight stay, complex equipment, expensive, & need available facilities.
Screening Instruments help estimate the risk of OSA:
- American Society of Anesthesiologists (ASA) check list
- Berlin Questionnaire
- Stop Model/Stop-Bang Questionnaire.
These look at S&S of OSA: snoring, observed apnea,, obesity, neck
circumference….
Chung, et al. evaluated use of serum HCO3 as an indicator of chronic
metabolic compensation for chronic recurrent respiratory acidosis (HCO3
> 28mmol) & a score of > 3 on the STOP-BANG questionnaire increased
specificity to 85%.
Stop-Bang Questionnaire
1. Snoring: Do you snore loud enough to be heard thru closed doors? Yes/No
2. Tired: Do you often feel tired, fatigued, sleep during day? Yes/No
3. Observed: Has anyone observed you stop breathing during sleep? Yes/No
4. Pressure: Do you have HBP? Yes/No
5. BMI: BMI > 35? Yes/No
6. Age: > 50 y/o? Yes/No
7. Neck Circumference: Greater than 40cm? Yes/No
8. Gender: Male? Yes/No
High Risk of OSA: yes to 3 or more questions Indicates high probability of OSA
Low Risk of OSA: yes to less than 3 questions
Chung, F., Subramanyam, R., Liao, P., Sasaki, E., Shapiro, C. & Sun, Y. High STOP-BANG score indicates a high
probability of obstructive sleep apnea. British Journal of Anesthesia, 2012.
108(5), 774.
ASA Guidelines
American Society of Anesthesiologists
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Preoperative Evaluation: interview, MR review, PE,
PSG,…Anesthesiologists should work with surgeon to develop a
protocol where pts with possibility of OSA are evaluated long
before day of surgery.
Preop initiation of NIPPV (noninvasive positive pressure
ventilation ) if severe OSA. Mandibular advancement devices
and preop weight loss should be considered.
ASA Guidelines (continued)
American Society of Anesthesiologists
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Use regional anesthesia – spinals and peripheral nerve blocks;
peripheral nerve catheters. Also agreement that excluding
opioids from spinals reduces risk.
Recommendation is to avoid general anesthesia and intubation.
Use local anesthesia when possible.
Caution against concomitant use of Benzo’s/barbituates which
increase risk of respiratory depression.
Avoid PCA’s with basal infusions.
ASA Guidelines (continued)
American Society of Anesthesiologists
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Use NSAIDS as much as possible.
Patient positioning: lateral, prone or 45 degree sitting. Avoid supine.
Recommend continuous pulse oximetry until room air sats are above
90% during sleep. Use of supplemental O2, as warranted.
Risk factors for postop respiratory depression:
Severity of OSA
Systemic use of opiods
Use of sedatives
Potential for apnea during REM rebound on POD #3-#4.
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Implications
•Patients with OSA are at increased risk of perioperative complications.
Results in need for more intense monitoring and strategies to prevent
adverse events.
•Implementation of a sedation scale.
Sedation precedes respiratory
depression 2/2 opioid administration. Sedation and respiratory
assessments should be done Q1-2h in the first 24h of surgery depending
on risk factors and presurgical screening. Increases demand on nursing
resources.
•Use of opiod analgesics, anxiolytics (Xanax), antihistamines (Benadryl,
scopolamine) and antiemetics can increase risk of postop respiratory and
cardiac complications.
Implications (continued)
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Information regarding the effects of length of OR time, and EBL is not
available from most of the studies because a lot of the studies are
retrospective and taken from databases, and this information is frequently not
available.
Information regarding readmission rates are not available from most of the
studies because a lot of the studies are retrospective and taken from
databases, and this information is frequently not available.
The use of simple screening tools now allows us to estimate the likelihood
someone has OSA, but what then is the next step?? Delay surgery? Or
proceed knowing the risk of complications is higher? Refer pt for workup and
treatment before surgery? Rate of noncompliance with treatment is high.
How long should a pt be treated with PAP before proceeding with surgery?
Implications (continued)
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There is little data to support the use of PAP in the acute
postoperative setting in improving outcomes, and cost is high so
adherence is low.
Be aware that patients are at risk for prolonged apnea during
sleep for up to 1 week after surgery due to interruptions in REM
sleep. It is imperative they use their CPAP during this time.
REM sleep can be lost during the initial postop period. REM
sleep may return in a rebound fashion with decreased
pharyngeal tone, hypoxemia and prolonged apnea.
References
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American Society of Anesthesiologists Task Force on the Perioperative Management of patients with
obstructive sleep apnea. Practice guidelines for the perioperative management of patients with obstructive
sleep apnea: an updated report by the American Society of Anesthesiologists Task Force on Perioperative
management of patients with obstructive sleep apnea. Anesthesiology 120 (2). 268-286. (2014)
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Chung, F., Subramanyam, R., Liao, P., Sasaki, E., Shapiro, C. & Sun, Y. High STOP-BANG score indicates a
high probability of obstructive sleep apnea. British Journal of Anesthesia, 2012; 108(5), 774.
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Memtsoudis, Stavros G., Besculides, Melanie C., & Mazumdar, Madhu. A rude awakening- the perioperative
sleep apnea epidemic. The New England Journal of Medicine, 2013; 368: 2352-2353.
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Memtsoudis, Stavros; Spencer, Liu S.; Yan, Ma; Chiu, Ya Lin; Walz, J. Matthias; Gaber-Bayllis, Licia K.; &
Mazumdar, Madhu. Perioperative Pulmonary outcomes in patients with sleep apnea after noncardiac surgery.
Anesthesia & Analgesia, 2011. 112(1): 113-121.
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Roop, Kaw; Pasupuleti, Vinay; Walker, Esteban; Ramaswamy, Anuradha; & Foldvary-Schafer, Nancy.
Postoperative complications in patients with obstructive sleep apnea. Chest, 2012. 141(2): 436-441.
•
Studndner, Ottokar; Opperer, Mathias; & Memtsoudis, Stavros G. Obstructive sleep apnea in adult patients:
considerations for anesthesia and acute pain management. Pain Management, 2015. 5(1): 37-46.
•
Veney, Amy J. Promoting safety of postoperative orthopaedic patients with obstructive sleep apnea.
Orthopaedic Nursing, 2013. 32(6): 320-324.
Post-Op Hypovolemic
Shock
http://youtu.be/d2mVKblkGcQ
Post-op Hypovolemic
Shock
 Pathophysiology
Acute reduction
blood volume
15%
(5L/750ml)
Death rate 30%
Peripheral
vasoconstrictio
n tachycardia
increased
myocardial
contractilityincrease
oxygen demand
Systemic
Inflammatory
Response
syndrome
(SIRS)
(Martel et al)
Tissue
hypoperfusion
from
vasoconstrictio
n anaerobic
metabolic/acido
sis
Post-Op Hypovolemic Shock
 Signs and symptoms
(Martel et al)
System
Early Shock
Late Shock
CNS
Altered Mental
Status
Obtunded
Cardiac
Tachycardia
Orthostatic
hypotension
Cardiac failure
Arrhythmias
Hypotension
Renal
Oliguria
Anuria
Respiratory
Tachypnea
Tachypnea
Respiratory failure
Hepatic
No change
Liver Failure
Gastrointestinal
No change
Mucosal Bleeding
Hematological
Anemia
Coagulopathy
Metabolic
None
Acidosis
Hypocalcemia
Hypomagnesium
Post-Op Hypovolemic Shock
 Early Treatment
 ORDER:
O Oxygenate
R Restore circulating volume (Crystalloid solutions,
blood transfusions)
D Drug Therapy
E Evaluate response to therapy (VS, Urine output,
mental status, CBC, CMP, PTT PTINR)
R Remedy underlying cause
Post-Op Hypovolemic Shock
 Late Treatment
 O Oxygenate
R Restore circulating volume (Crystalloid solutions,
blood transfusions)
D Drug Therapy Vasoactive agents Dopamine/
Norepinephrine) considered stress dose
steroids or antibiotics
E Evaluate response to therapy (VS, Urine output,
mental status, CBC, CMP, PTT PTINR)
R Remedy underlying cause
Post-Op Hypovolemic Shock
 Case Study DF
 ED Presentation and Care
 HPI 85 y/o female fell at home found by aide, on ground with
leg behind her. Hx dementia pt was treated at scene by EMS
with zofran 4 mg and Morphine sulfate 10mg IVP
 PMH Dementia, asthma, CHF, COPD, PSH rt rev THA
 Social hx 60yr smoking hx, lives w dtr, no ETOH
 PE: 50 kg, T 97.9 P 118 R 16 BP 100/57 oxygen saturations 93% 2L
NC rt leg deformity, pulses with doppler ECG at fib w VR 113
Post-Op Hypovolemic Shock
 Case Study DF
System
ED/2000
UNIT/0600
ICU/0800
CNS
Dementia-awake
unresponsive
unresponsive
Cardiac
HR 118 BP 100/57 HR 112
Hgb 11.9 wbc 11.8 BP146/115
CK 160, SR
Hgb 10.7 wbc
AT Fib w RVR
HR 110
BP 102/64
CK-437
AT Fib w RVR
Renal
NC
BUN 19 CR1.5
BUN 29 CR 3.0
Respiratory
BUN 27 CR 2.6
16
O2 sat-94% 3L
8-12 BG-Ph 7.157
O2 sat-100% NRB
R-12 BG Ph 7.2
O2 sat-99% 6L
Hepatic
SGOT-22
SGOT- 30
SGOT-48
Gastrointestinal
NPO
NPO
NPO
Metabolic
Na 142
K+ 4.6
Na 147
K+ 6.2
Na 144
K+ 4.9
Post-Op Hypovolemic Shock
Post-Op Hypovolemic Shock
Post-Op Hypovolemic Shock
Post-Op Hypovolemic Shock
Case Study
 Floor care
 O Oxygenate
R Restore circulating volume (Crystalloid solutions,
blood transfusions) none ordered
D Drug Therapy none ordered
E Evaluate response to therapy (VS, Urine output,
mental status, CBC, CMP, PTT PTINR)
R Remedy underlying cause
Post-Op Hypovolemic Shock
Case Study
 ICU care
 O Oxygenate
R Restore circulating volume (Crystalloid solutions,
blood transfusions) Normal Saline
D Drug Therapy
E Evaluate response to therapy (VS, Urine output,
mental status, CBC, CMP, PTT PTINR)
R Remedy underlying cause
Post-Op Hypovolemic Shock
 Conclusions
 Think about hypovolemia-early signs
 Aggressive fluid resuscitation
 Monitor I&O especially urine output
 Report abnormal findings
 Think about bleeding
References

Barbosa, N, Moraes, B, Souza, N, Rocha, F, Cavalho Barzil J “Hemostatic resuscitation in traumatic
hemorrhagic shock case report” Anesthesiology 2013 Jan-Feb;63(1) 99-102

Bartellas, E, Klien, M, Lane, C, Sprague, A, Wilson, A. “ Hemorrhagic Shock”, SOGC Clinical Practice
Guidelines. The Journal of Obstet Gynaecol Can 2012:24 (6):504-11

R. S. Braithwaite, N. F. Col, and J. B. Wong, “Estimating hip fracture morbidity, mortality and costs,” Journal of
the American Geriatrics Society, vol. 51, no. 3, pp. 364–370, 2003

M. Bumann, T. Henke, H. Gerngross, L. Claes, and P. Augat, “Influence of haemorrhagic shock on fracture
healing,” Langenbeck's Archives of Surgery, vol. 388, no. 5, pp. 331–338, 2003.. Martel,M , MacKinnon, C,.

Lichte, P Kobbe, P Pfeifer, R, Graeme, C Rainer, B, Mersedeh, T, Bergmann, C, Kadyrov, M, Fischer, H, Gluer,
C, Hildebrand, F Pape, H, Pufe, T “Impaired Fracture Healing after Hemorrhagic Shock” Mediators of
Inflammation Volume 2015 (2015), Article ID 132451, 7 pages.

S.-K. Lee and J. Lorenzo, “Cytokines regulating osteoclast formation and function,” Current Opinion in
Rheumatology, vol. 18, no. 4, pp. 411–418, 2006.
Small Bowel
Obstruction
Definition
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Small bowel obstructions are caused by a variety of pathologic processes.
An obstruction is a blockage of the intestine (small or large) which does
not allow the passage of food or fluids (mechanical or functional).
It is a frequent cause of hospitalization and surgery consult, representing
appx 20% of all surgery admission for abdominal pain.
Types of SBO
 Mechanical obstruction - is something that physically blocks the small intestine.
Causes:
1. Intestinal adhesions: #1 cause of SBO (small fibrous tissue in abdominal cavity)
2. Hernia
3. Tumors
4. Inflammatory bowel disease ie. Crohn’s Disease
5. Twisting of intestine (volvulus)
6. Telescoping of the intestine (intussusception)
7. Impacted Feces
Continued Types of SBO
 Paralytic Ileus/Functional Bowel Obstruction-can cause s/s of intestinal
obstruction, but doesn’t involve a physical blockage. It involves an impaired
gastrointestinal motility dysfunction by slowing the movement of food/fluid thru
the intestine.
Causes:
1. Abdominal surgery
2. Pelvic surgery
3. Infection
4. Certain Medications-antidepressants, narcotics, anesthesia
5. Muscle/Nerve Disorders-ie. Parkinson’s Disease
6. Constipation is the #1 associated factor for ileus after ortho surgery incidence
The incidence of ileus after lower limb reconstruction ranges from 0.3%-2.0%
w/an even higher incidence (5.6%) following revision THA
(Lee et al)
Pathophysiology of SBO
Partial vs Complete
 Significant obstruction is associated with increased intestinal contractions
proximal to the site of the obstruction and are associated with abdominal
cramps.
 With complete unrelieved obstruction bowel contents fail to pass distally,
resulting in accumulation of fluids causing distention/dilation of the
proximal bowel.
 As pressure in the bowel proximal to the obstruction increases blood flow
decreases which can result in :
1.
2.
3.
4.
5.
6.
Hemorrhage
Ischemia/Necrosis
Infarction of the bowel
Perforation-as a result of ischemia
Sepsis/peritoneal infections/shock
Death
Pathophysiology of SBO
(continued)
 In simple obstruction the proximal bowel appears heavy,
edematous, and even cyanosed.
 Acute SBO results in volume depletion and electrolyte imbalance.
 Vomiting
 Loss in the peritoneal cavity (fecal fluid)
 Intestinal contents are cut off from the absorptive surface of the
colon
History Taking
 Good history taking on admission is important
 Last bowel movement and usual pattern
 Abdominal history of pelvic/colon disease ie. CA, radiation,
inflammatory bowel disease
 Has the patient ever experienced any complications r/t any
previous surgeries in the past (ie. SBO)
 Remember abdominal adhesions is the #1 cause of mechanical
SBO
 Remember Constipation is the #1 cause of functional SBO
Signs & Symptoms
Small bowel obstruction is considered a medical
emergency
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Signs & Symptoms:
- Nausea
- Constipation
- Abdominal Pain - colicky in nature
- Abdominal distension
- Vomiting - is a pronounced symptom in SBO
Other Sign & Symptoms that are more ominous:
- Fever
- Tachycardia & associated hypotension
Assessment
In the focused gastrointestinal assessment consider the following:
1.
2.
3.
4.
5.
6.
Vial Signs - fever, tachycardia with associated hypotension
Nausea
Vomiting
Bowel Sounds - hypoactive, tinkling, absent
Abdominal Distension
Constipation
Other items to consider are: Medications & past medical history
Imaging Work-Up Algorithm
Imaging for SBO
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Plain abdominal xrays provide the most valuable
information in the initial diagnosis of acute SBO, in
appx 50-60% of cases this type of imaging will provide
enough information needed for clinical decision making
(proves to be low cost & effective).
Ct scans are used when xrays are equivocal, normal,
or low grade partial SBO is suspected & is 85%-95%
accurate in diagnosis.
(Silva et al)
Radiology Classification of SBO
High grade vs Low grade
High Grade SBO:
Multiple air fluid levels with a width of 2.5 cm or more
Vertical height of more than 2 cm b/t air fluid levels
Distension of small bowel diameter more than 2.5 cm & a
small bowel-colon diameter ratio greater than 0.5
Delay in passage of CT contrast
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Low Grade SBO:
Sufficient flow of contrast material through obstruction
Less air fluid levels
Still will see distension of the small bowel
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(Silva et al)
Examples of High grade
SBO on Xray
High-grade SBO. Plain abdominal
radiograph shows multiple air-fluid
levels (arrows), some with a width of
more than 2.5 cm. In addition, there is
a differential vertical height of more
than 2 cm between corresponding airfluid levels in the same bowel loop
(circled area). There is also distention
of the small bowel diameter to more
than 2.5 cm and a small bowel–colon
diameter ratio of greater than 0.5.
(Silva et al)
High grade SBO Xray
(AlReefi & Shukri)
Surgical view of High grade SBO
(Al Reefi & Shukri)
Further Diagnostic Work-Up
Other Diagnostic Testing :
 CBC-leukocytosis
 BMP-if bun & creatine are elevated may indicate
dehydration
 UA
 LFT
 Pancreatic enzymes
Further Diagnostic Work-Up
(continued)
Other Differential Diagnosis to Consider:
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Gastroenteritis
Pancreatitis
UTI
Cholecystitis
Inflammatory Bowel Disease
Appendicitis
Treatment of SBO
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Aggressive resuscitative fluid therapy
Electrolyte imbalance correction
NPO
Decompression of stomach-NGT helps prevents aspiration
Foley Catheter for strict I&O
Labs: CBC, BMP, LFT’s, Pancreatic enzymes, UA
Analgesics – morphine based
Antibiotic Therapy - broad spectrum used for prophylaxis in surgical
intervention
 General surgery consult
 Antimetics: zofran, reglan, tigan, compazine

Stay away from scopolamine patches (can cause constipation, decreased gut motility, and
even bowel stasis by mechanism of anticholinergic effect)
(Kulaylat & Doerr)
Prognosis of SBO
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With proper diagnosis & txmt of SBO the prognosis is good. Complete
obstructions treated successfully non-operatively have a higher incidence
of reoccurrence than do those treated surgically.
Mortality & Morbidity are dependent on early recognition & correct
diagnosis of obstruction. If untreated or strangulation occurs-death is
100%. If surgery is performed within 36 hrs mortality decreases to 8%.
Factors associated with death & post-operative complications include:
- age
- comorbidity
- txmt delay
(Nobie et al)
Case Presentation #1
K.W. a 66 yr female admitted for an elective right THA , last BM was 3 days
PTA
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PMHX: HTN, DM, hypercholesterolemia, CAD, gerd, constipation,
hypothyroidism, OA
PSX Hx: TKA, hysterectomy, goiter removal, right thumb sx
Recd from recovery with N/V, recd spinal anesthesia non duramorph
Continued to have N/V up until day of discharge on POD #2 which had
resolved prior to dc: had recd mutliple IV boluses, reglan, no abdominal
xr was done.
Assessment: +bs x 4, + flatus per pt, abd soft, nontender, nondistended.
Zofran. +flatus per patient. No BM on day of DC. Had recd K-dur x 1 for
hypokalemia on POD #1
Readmitted POD #4 with a SBO thu the ED.
Assessment: abd mildly distened, mild diffuse tenderness no rebound
tenderness or guarding. No flatus since dc, no bm, continues w/N&V
Case Presentation #1
(continued)
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Abdominal xr revealed a high-grade SBO may be early w/ileus.
+leukocytosis. + Electrolyte imbalance. Further information
gathering from the patient revealed that she experienced a SBO
w/her hysterectomy yrs ago.
Medications upon admission consisted of: percocet, senna S,
zetia, lipitor, insulin, toradol, synthroid, benicar, cozaar, protonix,
miralax, xalerto, livalo, dexilant, dilaudid
Case Presentation #1
(continued)
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Txmt: consisted of conservative mgt w/fluids, pain mgt,
antiemetics, NGT, NPO, strict I&O, serial lab draws & xr. Patient
failed conservative mgt & underwent an exp. Lap on POD# 9
w/extensive lysis of adhesions over 2 hrs, small bowel resection.
Patient continued to fail txmt & was taken back 9 days later for a
2nd exp lap & at that time sustained a bowel perforation, further
bowel resection, G-tube insertion, sepsis, ICU mgt for septic
shock. TPN & lipids for nutrition. DC appx 1 month later on the 2nd
admission.
Patient returned to ED w/abdominal pain 2 additional times w/o
evidence of SBO
Case Presentation #2
C.B. a 74 yr female admitted for elective left TKA recd. Spinal anesthesia with a
femoral nerve block
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PMHx: AFIb w/cardoversion, HTN, hypercholesterolemia
PSX Hx: TKA, Shoulder sx, finger sx, back sx, cataract sx
Day of admission no N&V, abd was soft, non distended, non tender, hypoactive bs,
last BM was the day PTA
Patient experienced pain control issues and narcotic strength was increased to
percocet 10/325
POD #1: +N&V, no flatus, continued w/hypoactive bs. Labs wnl. Recd multiple IV
boluses & reglan
POD #2: in AM nausea resolved; but in PM returns. +flatus per pt. No BM. Abd xr
reveals gas filled on dilated transverse/descending colon-non obstructive bowel gas
pattern. No mention of an ileus. NGT was inserted, made NPO, continual IV fluids.
Consult for general sx placed.
POD #3: abd xr repeated reveals mildly dilated loop small bowel LUQ likely
representing ileus & a large amt of stool. Ducolax suppository was given resulting
in lg BM, NGT clamped, & DC tolerated clear liquid diet.
POD #4 DC home. Narcotics were changed to ultram upon dc
Conclusions
 SBO is considered a medical emergency
 Intervene early & be aggressive
 Consider all hx of pt & when clinical picture isn’t making
sense ask again
 Evaluate all medications
 Do a very focused GI assessment
 Tx constipation early in ortho post-op pt
 Notify physician early & ask for them to evaluate pt status
Questions??????
Thank You!!!
References

Al Reefi, M.A. & Shukri, N. Missed small bowel obstruction that complicated an acute
appendicitis: A Misdiagnosis. Grand Rounds. Specialities: Case Report Article Type:
Specialities Paediatric Surgery, 26 March 2013 e-med Ltd. Vol 13, pg 36.44.

Kulaylat, M. N. & Doerr, R. J. Surgical Treatment: Evidence-Based & Problem-Oriented small
bowel obstruction, 2001. www.nebl.nlm.nih.gov/book/NBK6873/accessed April 12, 2015.

Lee T.H., Lee, J.S., Hong, S.J., Jany Young J., Jeon, S. R., Byrum, D.W., Park Young, W., Kim
S.I., Choi, H.S., Lee, J.C., & Lee, J.S. Risk Factors for Post-Operative Ileus Following
Orthopedic Surgery: The Role of Chronic Constipation. J. Neurogastroenterol Motil., 2015 Jan;
21(1): 121-125.

Nobie, Brian A. Small-Bowel Obstruction. Medscape Reference: Drugs, Diseases &
Procedures. Updated: Jan 20, 2015.

Silva, A. C, Pimenta, M., and Guimaraes, L. Small Bowel Obstruction: What to Look For.
RadioGraphics. March-April 2009, 29 (2).