hyperbaric oxygen for wound healing - peacehealth> patient has a wound classified as wagner grade...
TRANSCRIPT
Objectives By the end of this lecture, attendees should be able to:
> Describe the history of hyperbaric medicine> Describe conditions where hyperbaric oxygen therapy can improve
patient outcomes> Associate the mechanisms of hyperbaric oxygen therapy with the
conditions for which hyperbaric oxygen therapy has been shown to improve patient outcomes
> Identify patients for whom hyperbaric oxygen therapy may be helpful
I have no relevant financial relationships to disclose
A BRIEF HISTORY OF HBO2
Part 1
Henshaw 1662 First recorded attempt to use changes in atmospheric pressure for
a therapeutic effect Inspired by salutary effects associated with changes in climate
(elevation)
Henshaw 1662 “Domicilium”
> Sealed room attached to a pair of organ bellows> Atmosphere could be “condensed” or “rarified” by compressing or
decompressing the room
Condensed atmosphere used to treat “acute” conditions Rarified atmosphere used to treat “chronic” conditions
“ In times of good health this domicilium is proposed as a good expedient to help digestion, to promote insensible respiration, to facilitate breathing and expectoration and consequently, of excellent use for prevention of most affections of the lungs”
Late 19th Century
Available in most European cities
Advertised like health spas
Forlanini 1875 Specialized in the treatment of tuberculosis and other respiratory
disorders Started a “pneumatic institute” in Milan, Italy Credited with the creation of the first horizontal hyperbaric
chamber
The Industrial Revolution Coal replaced wood as the primary fuel source The search for coal led miners to deposits beneath the Loire River
and quicksand Mine shafts rapidly filled with water
Caisson Work French for “box” Some caissons were pressurized to as high as 4.25 atm abs (107
fsw equivalent) Typical work shifts were 4 hours (240 min)
Triger c.1850 French paleontologist and mining engineer Designed inter-connecting 5-foot diameter
circular steel rings Weight of the steel rings forced its way
deeper into the soft bottom of the riverbed as sand and earth was excavated
Additional rings added until the shaft reached the coal deposits
Air lock installed at the top Compressed air introduced into shaft to force
water and moist sand out
Used with permission of Best Publlshing
Triger’s notes after exposure “Knee pain appeared in the left side, and we felt a rather severe
painful discomfort for several days… After we were quite free of these pains, we were anxious to try the experiment again. At the same hour, this is, 20 hours our exit from compressed air, we felt in the right side pains just like the former ones, which kept us numb for four or five days”
Eads Bridge 1869 Designed and built by Captain James B. Eads World’s first steel arch bridge span built in St. Louis, MO to cross
the Mississippi river First bridge to span a body of water using caissons
Eads Bridge 1869 Exposures within the caissons reached 4.45 atm abs (114 fsw) 352 workers
> 5% died> 10% suffered serious symptoms of decompression sickness
Brooklyn Bridge 1870 Smith recommended that a recompression chamber be made
available on site, but this recommendation was not followed Roebling suffered permanent paralysis after repeated visits to the
caissons and supervised the construction from his bedroom, which overlooked the construction site
Fontaine 1879 Created the first mobile hyperbaric chamber and surgical suite
capable of holding 12 people Realized that nitrous oxide was more effective during pressurized
surgeries> Fewer side effects and faster recovery times
Died during construction of a hyperbaric surgical amphitheater designed to hold 300 people
Cunningham c.1918 Chairman of the Dept. of Anesthesiology at Kansas University
Medical School Noted that the Spanish Flu pandemic’s highest morbidity and
mortality were in areas of higher elevation than in coastal regions Borrowed a hyperbaric chamber and began treating influenza
patients with promising results
The Cunningham Sanitarium
Courtesy of Stuart Miller, MD
Courtesy of Stuart Miller, MD
Courtesy of Stuart Miller, MD
Courtesy of Stuart Miller, MD
Courtesy of Stuart Miller, MD
The end of an era Cunningham was challenged by the American Medical
Association’s Bureau of Investigation and was eventually censured in 1928
He retired in 1935 The “steel ball hospital” was converted to a conventional hospital
but closed in 1940 and scrapped for metal in the war effort
Hyperbaric Medicine Facilities in the US
Courtesy of Tom Workman
0
200
400
600
800
1000
1200
1400
1971 1981 1986 1996 1999 2000 2004 2005 2008 2010 2013 2015
Monoplace hyperbaric chamber
What is NOT hyperbaric medicine
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Intermountain Regional Medical Center – Rectangular Chamber
Courtesy of Jim Holm, MD
MECHANISMS OF HBO2
Part 2
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Pressure Effects
Depth(fsw)
Pressure(ATA)
Volume(% change)
Diameter(% change)
BubbleSize
BubbleLength
0 1 100 100
33 2 50 79.3
66 3 33 69.3
99 4 25 63.3
132 5 20 58.5
165 6 17 55.0
Hyperoxygenation Higher amounts of oxygen are dissolved in the body
> Hyperbaric oxygen therapy allows enough oxygen to be carried in the plasma to maintain tissue oxygenation in the absence of blood (ischemia)
Hyperoxygenation Higher amounts of oxygen are dissolved in the body
> Hyperbaric oxygen therapy allows enough oxygen to be carried in the plasma to maintain tissue oxygenation in the absence of blood (ischemia)
Carbon Monoxide poisoning first treated in 1962> CO binds to hemoglobin 200 times stronger than oxygen, but
hyperbaric oxygen can force it off of the hemoglobin
Acute blood loss anemia> Patients who cannot get a transfusion right away can be kept alive
with repeated treatments
Angiogenesis with HBO2
Angiogenesis is assumed based on Marx’s research on CRTI> Increase in capillary density as measured by TCOM> This mechanism has been extrapolated to other tissue locations and
disease conditions
Angiogenesis in Irradiated Tissue
Svalestad J, et al Int J. Oral Maxillofac Surg, 2014 and 2015
Slide Courtesy of James Holm, MD
Angiogenesis in Irradiated Tissue
Svalestad J, et al Effect of hyperbaric oxygen treatment on oxygen tension and vascular capacity in irradiated skin and mucosa. Int J. Oral Maxillofac Surg, 43: 107-112. 2014
Gingival Blood Flow (via LDF) Skin Blood Flow (via LDF)
Slide Courtesy of James Holm, MD
Angiogenesis in Irradiated Tissue
Svalestad J, et al Effect of hyperbaric oxygen treatment on oxygen tension and vascular capacity in irradiated skin and mucosa. Int J. Oral Maxillofac Surg, 43: 107-112. 2014
Slide Courtesy of James Holm, MD
Enhanced Antibacterial Effects White Blood Cell function
> WBCs bind to bacteria> They use oxygen based mechanisms to kill the bacteria> Less effective in areas with low oxygen
Gas Gangrene first treated in 1961> Solders in WWI were treated by injecting oxygen directly into
gangrenous limbs> Bacteria are anaerobic, so oxygen suppresses them> Toxin production is inhibited at high oxygen concentrations
0.0
0.5
1.0
1.5
2.0
Pre- Post-HBO2 #1
Pre- Post-HBO2 #10
Pre- Post-HBO2 #20
% C
D 3
4+ IN
GA
TED
CEL
L PO
PULA
TIO
N* * * * *
HUMAN STEM CELL MOBILIZATION BY HBO2
n=26
2 X 8 X- PATIENTS PREVIOUSLY EXPOSED TO RADIATION -
Am. J. Physiology 290: H1378, 2006
Slide Courtesy of Stephen Thom, MD
2.0 ATA O2 for 2 hours 2.5 ATA O2 for 1.5 hours
CD
34+ /
CD
45-S
PC
s/ µ
l blo
od
0
20
40
60
80
100
**
*Stem Cell Research 12: 638, 2014
HBOT CAN MOBILIZE STEM CELLS:
Slide Courtesy of Stephen Thom, MD
Ischemia-Reperfusion Injury Conditions where there is period of low or no blood flow then a
period where blood flow is restored Results in paradoxical tissue swelling and damage
> Compromised surgical flaps and grafts> Carbon monoxide poisoning
Reduces inflammation> Hyperbaric oxygen prevents WBCs from “sticking” to blood vessel
walls after a period of low blood flow> “Sticky” WBCs release inflammatory factors that cause leaky blood
vessels and swelling and damage> Has shown decreased morbidity and mortality in sepsis models
Attenuation of I-R injury
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http://www.acssurgery.com/acssurgery/secured/figTabPopup.action?bookId=ACS&linkId=part08_ch27_fig2&type=fig
Binding of human neutrophils (in vitro)
HBO2 mechanisms for Wound Healing Hyperoxygenation Decreases bubble size Peripheral vasoconstriction Angiogenesis Stem cell mobilization Fibroblast proliferation/Collagen Synthesis Reduced leukocyte adhesion Reduced lipid peroxidation Edema reduction Enhanced leukocyte antimicrobial activity Antibiotic synergy Toxin inhibition
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INDICATIONS FOR HYPERBARIC OXYGEN THERAPY
Part 3
Indications for Hyperbaric Oxygen Decompression Sickness
Arterial Gas Embolism
Carbon Monoxide Poisoning
Chronic Radiation Tissue Injury
Selected Non-healing Wounds
> Diabetic Wounds of the Lower Extremities
Traumatic Peripheral Ischemia
Chronic Osteomyelitis
Thermal Burns
Exceptional Blood Loss Anemia
Gas Gangrene, Myonecrosis, Necrotizing Soft Tissue Infections
Compromised Skin Flaps
Acute Peripheral Arterial Insufficiency
Intracranial Abscess
Primary Therapy
Adjunctive Therapy
Elective Indications These indications are usually performed on an outpatient basis Patients are hemodynamically stable and are often carrying out
their activities of daily living> Treatment typically interrupts their day to day schedule> Many patients complain about the need to come so frequently> Referring physicians often undermine the treatment plan because
they give in to the patient’s sense of incovenience
Bread and butter for hyperbaric facilities Evidence for some indications is stronger than for others
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Elective Indications for Hyperbaric Oxygen Decompression Sickness
Arterial Gas Embolism
Carbon Monoxide Poisoning
Chronic Radiation Tissue Injury
Selected Non-healing Wounds
> Diabetic Wounds of the Lower Extremities
Traumatic Peripheral Ischemia
Chronic Osteomyelitis
Thermal Burns
Exceptional Blood Loss Anemia
Gas Gangrene, Myonecrosis, Necrotizing Soft Tissue Infections
Compromised Skin Flaps
Acute Peripheral Arterial Insufficiency
Intracranial Abscess
Urgent Indications for Hyperbaric Oxygen Decompression Sickness
Arterial Gas Embolism
Carbon Monoxide Poisoning
Chronic Radiation Tissue Injury
Selected Non-healing Wounds
> Diabetic Wounds of the Lower Extremities
Traumatic Peripheral Ischemia
Chronic Osteomyelitis
Thermal Burns
Exceptional Blood Loss Anemia
Gas Gangrene, Myonecrosis, Necrotizing Soft Tissue Infections
Compromised Skin Flaps
Acute Peripheral Arterial Insufficiency
Intracranial Abscess
SELECTED NON-HEALING WOUNDS (DIABETIC FOOT ULCERS)
Part 3
Diabetic Foot Ulcers Diabetes has a constellation of pathologies
> Autonomic neuropathy Mechanical Deformities (e.g., clawfoot and hammertoe)
> Sensory neuropathy Loss of protective sensation
> Hyperglycemia Osmotic diuresis Limits neutrophil functioning Increased catabolism
> Microvascular disease Lack of hyperemic response to injury Decrease oxygen diffusion across basement membrane
> Macrovascular disease Increased atherosclerosis of lower extremity vessels
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Wagner Grades
Wagner, FW The Dysvascular Foot, Foot & Ankle 2(2) 1981
CMS requirements Diabetic wounds of the lower extremities in patients who meet the
following three criteria:> Patient has type I or type II diabetes and has a lower extremity wound
that is due to diabetes;> Patient has a wound classified as Wagner grade III or higher; and> Patient has failed an adequate course of standard wound therapy.
The use of HBO therapy is covered as adjunctive therapy only after there are no measurable signs of healing for at least 30 –days of treatment with standard wound therapy and must be used in addition to standard wound care… Failure to respond to standard wound care occurs when there are no measurable signs of healing for at least 30 consecutive days. Wounds must be evaluated at least every 30 days during administration of HBO therapy. Continued treatment with HBO therapy is not covered if measurable signs of healing have not been demonstrated within any 30-day period of treatment.
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National Coverage Determination (NCD) for Hyperbaric Oxygen Therapy (20.29)
Hyperbaric Medicine Facilities in the US
Courtesy of Tom Workman
0
200
400
600
800
1000
1200
1400
1971 1981 1986 1996 1999 2000 2004 2005 2008 2010 2013 2015
DFU
Recommendation 1 In patients with Wagner Grade 2 or lower diabetic foot ulcers, we
suggest against using hyperbaric oxygen therapy (very low-level evidence in support of HBO2, conditional recommendation)
Recommendation 2 In patients with Wagner Grade 3 or higher diabetic foot ulcers that
have not shown significant improvement after 30 days of treatment, we suggest adding hyperbaric oxygen therapy to the standard of care to reduce the risk of major amputation and incomplete healing (moderate-level evidence, conditional recommendation)
Effects of HBO2
Study Study Design
% Healed ∅Major Amp
Delay before HBO2?
Increases Healing
Percentage
Decreases Major
Amputations
Increases Rate of Healing
Increases Durability of
Healing
↑PtcO2 after HBO2
Baroni 1987 PCoT 89 vs 10 No Yes Yes n/a Maybe n/a
Oriani 1990 RCoT 96 vs 67 No Yes Yes n/a n/a n/a
Doctor 1992 RCT 87 vs 53 NS Yes Yes Maybe n/a n/a
Faglia 1996 RCT 91 vs 67 No Yes Yes n/a n/a Yes
Zamboni 1997 PCoS 80 vs 20 Yes > 6mo Maybe No Yes n/a n/a
Faglia 1998 RCoT 86 vs 69 No Yes Yes n/a n/a n/a
Lin 2001 RCT n/a NS n/a n/a n/a n/a Yes
Kalani 2002 PCoT 76 vs 48 Yes > 8 wks Maybe Maybe Maybe n/a n/a
Abidia 2003 RCT 63b vs 0 Yes > 6 wks Yes No Yes Maybe No
Kessler 2003 RCT 14c vs 0 Yes > 3 mos Maybe No Yes n/a No
Duzgun 2008 RCT 74 vs 18 Yes > 4 wks Yes Yes n/a n/a n/a
Löndahl 2010 RCT 52 vs 29 Yes > 3 mos Yes No n/a n/a n/a
Ma 2013 RCT n/a Yes > 8 wks n/a n/a Yes n/a Yes
Margolis 2013 RCoT 43 vs 50 Yes > 8 wks No No No No n/a
aReported improvement, not healing bonly at1 year follow-up c4 week follow-up
Recommendation 3 In patients with Wagner Grade 3 or higher diabetic foot ulcers who
have just had a surgical debridement of an infected foot (e.g., partial toe or ray amputation; debridement of ulcer with underlying bursa, cicatrix or bone; foot amputation; incision and drainage [I&D] of deep space abscess; or necrotizing soft tissue infection), we suggest adding acute post-operative hyperbaric oxygen therapy to the standard of care to reduce the risk of major amputation (moderate level evidence, conditional recommendation).
COMPROMISED FLAPS AND GRAFTS
Part 4
Graft vs. Flap Graft – a tissue that is completely separated from any blood
supply.> Non-vascularized.
Flap – a tissue that retains some form of blood supply.> May be vascularized locally or by a distant blood supply via
microsurgical techniques.
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Graft Physiology Simple Grafts
> Composed of a single tissue type (skin)
Composite Grafts> Composed of multiple tissue types (skin, muscle, cartilage, bone)
Grafts rely on the wound bed for survival and “take”.> Thicker and larger grafts (full thickness skin graft) have a higher
requirement than smaller and thinner grafts (split thickness skin graft).> Composite grafts have an even higher metabolic requirement due to
the multiple tissue types
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Random Flaps Blood supply comes from un-named subcutaneous vessels
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Axial Flap Blood supply is still attached to its source but tissue is relocated
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http://www.plasticsurgerynow.com/breast-procedures-washington-dc/breast-reconstruction/
Free Flap Blood supply is separated from its source and has to be re-stored
in a new location
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http://www.plasticsurgerynow.com/breast-procedures-washington-dc/breast-reconstruction/
Why do flaps fail? Blood supply is insufficient to maintain viability of the flap
> Arterial supply> Venous congestion> Poor recipient bed
Irradiated tissue Peripheral arterial disease
> Bad technique (excessive size of flap/graft)> Long ischemic times
Excessive external forces> Shear > Pressure> Trauma
Degloving injuries
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Rationale for Hyperbaric Oxygen Not recommended for the support of normal, uncompromised flaps
or grafts Indicated for flaps in compromised tissue
> Previous radiation> Decreased perfusion/hypoxia> Traumatic amputations/degloving injury
Hyperbaric oxygen can> Maximize viability of the compromised tissue> Reduce the need for re-grafting or repeat flap procedures> Decrease patient morbidity
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History 68 yo female s/p bilateral mastectomy with immediate TRAM
reconstruction 15 hour procedure complicated by clotting of end-to-end
anastamoses Flap reassessed the next day and HBO2 initiated
> Thursday evening at 11 pm
Pre-HBO2 After 3 HBO2
After 5 HBO2 After 7 HBO2
Post-op day 72
HBO2 mechanisms for Wound Healing Hyperoxygenation Decreases bubble size Peripheral vasoconstriction Angiogenesis Stem cell mobilization Fibroblast proliferation/Collagen Synthesis Reduced leukocyte adhesion Reduced lipid peroxidation Edema reduction Enhanced leukocyte antimicrobial activity Antibiotic synergy Toxin inhibition
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