SHARM EL-SHEIKH INTERNATIONAL HOSPITAL

GENERAL MANAGER

DrMOHAMMED FATHALLAH BARAKAT

Anaesthesia consultant Military Armed Forces

HYPERBARIC DEPARTMENT

Hyperbaric Doctors Staff

Dr .Magdy Al Mosalamy Internal medicine consultant and vice manager

Dr .Magdy Al ShorbagyE.N.T consultant

Dr .George Magdy Emergency Medicine and Critical Care resident

Dr. Abeer Abd El Malak Internal Medicine and Nephrology resident

HYPERBARIC OXYGEN

Presented by

Dr. George Magdy TawfikEmergency medicine and Critical care

Diving and Hyperbaric medicine

DEFINITION

Hyperbaric oxygen (HBO2) is a treatment, in which a patient breathes 100% oxygen intermittently while inside a treatment

chamber at a pressure higher than sea level pressure (i.e., >1 atmosphere absolute; atm

abs). 

Mechanism

1. Vasoconstriction

 which can lead to a 20% decrease in regional blood flow

 hypoxia may develop; however, this is not the case with HBO2.

 The decrease in regional blood flow is more than compensated for by the increased plasma oxygen that reaches the tissue.

 The net effect is decreased tissue inflammation without

hypoxia--a mechanism by which hyperbaricoxygen therapy is believed to improve crush injuries, thermal

burns, and compartmentsyndrome

 

2. NEOVASCULARIZATION AND EPITHELIALIZATION

 71- accelerate the development of new blood vessels . This can be induced in both acute and chronic injuries.

2- Regenerating epithelial cells also function more effectively in a high-oxygen environment .These effects have proven effective in treating

tissue ulcers and skin grafts .

3. STIMULATION OF FIBROBLASTS AND OSTEOCLASTS.

 

1- In a hypoxic milieu, fibroblasts are unable to synthesize collagen, and osteoclasts are unable to lay down new bone .

2- Collagen deposition, wound strength, and the rate of wound healing are affected by the amount ofThe available oxygen. 

This mechanism may play a role in the treatment of osteomyelitis and

slowly healing fractures.

4. IMMUNE RESPONSE

1- Studies have shown that the local tissue resistance to infection is directly related to the level of oxygen found in the tissue .

2- High oxygen concentrations may prevent the production of certain bacterial toxins and may killcertain anaerobic organisms such as Clostridium perfringens.  3- Oxygen is believed to aid the migration and phagocytic function of the PMN . Oxygen is converted within the PMN into toxic substrates (superoxides, peroxides, and hydroxyl radicals) that are lethal to bacteria .

 These effects on the immune system allow HBO2 to aid the

healing of soft-tissue infections and osteomyelitis

5. MAINTAINING HIGH-ENERGY PHOSPHATE BONDS

 HBOT can reduce lactic acid released from ischemic parts

HBOT increases ATP which is the energy factor used for nutrition and regeneration of tissues

INDICATIONS

INDICATIONS APPROVED BY UHMS (EUROPEAN UNDERSEA AND HYPERBARIC MEDICAL SOCIETY)

1. DECOMPRESSION SICKNESS: DIVING ACCIDENT

(DCS) refers to symptoms caused by blocked blood supply, damage from direct mechanical effects, or later biochemical actions from suspected bubbles evolving from inert gas dissolved in blood or tissues when atmospheric pressure decreases too rapidly which is mainly nitrogen .

These nitrogen gas bubbles can block blood vessels leading to ischaemia and as a result manifestations differ according to site involved.

DCS can occur after scuba diving, ascent with flying, or hypobaric or hyperbaric exposure.

Clinical picture of DCS

Role of Hyperbaric O2 in DCS

1- HBOT is used to diminish the size of the bubbles, not simply through pressure According to Boyle’s law (the volume of the bubble becomes smaller as pressure increases) With a change in 1.8 ATA, this is only about 30%. The bubble causing DCS is thought to be composed of nitrogen

2- An alternative pathway for oxygen perfusion in plasma rescue cells from death due to the ischaemia 2formed by the gas bubbles in blood stream.

3- During HBOT, the patient breathes 100% oxygen, creating oxygen-rich, nitrogen-poor blood. This creates a gradient of nitrogen between the blood and the bubble, causing nitrogen to efflux from the bubble into the bloodstream, which, in effect, makes the bubble smaller.

2. AIR OR GAS EMBOLISM: SAME MECHANISM AS DCS

HBOT can reduce gas buubles by pressure and provide an adequate oxygenation

through plasma instead of blocked bllod vessels by interrupted blood stream by air

emboli bubbles

3. CARBON MONOXIDE POISONING

1- oxygen competitively displaces CO from hemoglobin. While breathing room air, this process takes about 300 minutes in normal air . This time is shortened to 32 minutes with HBOT

2- restores cytochrome oxidase aa3/C[36] and helps to prevent lipid peroxidation.

3- HBOT is also used to help prevent the delayed neurologic sequelae

4. CLOSTRIDIAL MYOSITIS AND MYONECROSIS (GAS GANGRENE):

1- HBOT kills anaerobic bacilli

2- HBOT activate immune system

3- HBOT reduce oedema and swelling by it’s vasoconstriction effect on blood vessels

4- HBOT promotes healing and regeneration of damaged tissue by activation of fibroblasts and collagen synthesis

BEFORE

AFTER

5. CRUSH INJURY, COMPARTMENT SYNDROME AND OTHER ACUTE TRAUMATIC ISCHEMIAS:

1- hyperoxygenation by increasing oxygen within the plasma

2- HBOT also induces a reduction in blood flow that allows capillaries to resorb extra fluid, resulting in decreased edema. As a gradient of oxygenation is based on blood flow, oxygen tissue tensions can be returned, allowing for the host defenses to properly function.

3- decreased neutrophil adherence to ischemic venules is observed with elevated oxygen pressures (2.5 ATA).[15, 16] Reperfusion injury is diminished, as HBOT generates scavengers to destroy oxygen radicals

6. ARTERIAL INSUFFICIENCIES:

Central Retinal Artery Occlusion

Visual improvement has been reported even with delay of HBOT.

7. ENHANCEMENT OF HEALING IN SELECTED PROBLEM WOUNDS:

Wounds that fail to heal are typically hypoxic.

Multiple components of the wound healing process are affected by oxygen concentration or gradients, which explains why hyperbaric oxygen therapy (HBOT) can be an effective therapy to treat chronic wounds.

1- Angiogenesis occurs in response to high oxygen concentration by promoting collagen synthesis

2- fibroblast proliferation and collagen synthesis are oxygen dependent HBOT likely stimulates growth factors and other mediators of the wound healing process.

3- Hyperbaric oxygen also has been shown to have direct and indirect antimicrobial activity by leukocytes activation

8. SEVERE ANEMIA:

The major oxygen carrier in human blood is hemoglobin, transporting 1.34 mL of oxygen per gram

HBOT creates an alternative pathway for oxygen transport via plasma by increasing O2 levels from 0.3mg/l in normobaric pressure to 6.8 mg/l in hyperbaric atmosphere 3 ATA

(life without blood)In 1960 an experiment was carried in Netherlands by removing all the blood from rats and injection of plasma instead in rats then let them live in hyperbaric chamber . Results was marvelous. The HBOT could do an adequate oxygenation and perfusion through plasma in total absence of RBCS

9. INTRACRANIAL ABSCESS

10. NECROTIZING SOFT TISSUE INFECTIONS

1- The cornerstones of therapy are wide surgical debridement and aggressive antibiotic therapy Hyperbaric oxygen therapy (HBOT) is used adjunctively with these measures, as it offers several mechanisms of action to control the infection and reduce tissue loss.2- HBOT is toxic to anaerobic bacteria

3- HBOT improves polymorphonuclear function and bacterial clearance.4- HBOT may decrease neutrophil adherence based on inhibition of beta-2 integrin function

5- HBOT can stop the production of the alpha toxin.

6- HBOT may facilitate antibiotic penetration or action in several classes of antibiotics, including aminoglycosides, cephalosporins, sulfonamides and amphotericin7- HBOT Promotes regeneration and growth of tissues8- HBOT activates leukocytes

11. OSTEOMYELITIS

1-n promoting osteoclast function. Which can do resorption of necrotic bone 2- HBOT facilitates the penetration or function of antibiotic drugs.

3- HBOT previously discussed can do neovascularization and blunt the inflammatory response, likely provide additional benefit.

Aseptic necrosis of right femur

12. DELAYED RADIATION INJURY (SOFT TISSUE AND BONY NECROSIS)Radiation induced rectal ulcer treatment

13. COMPROMISED GRAFTS AND FLAPS: The underlying pathophysiology of all compromised grafts and flaps is hypoxia

1- HBOT benefits patients by reducing the oxygen deficit.

2- A unique mechanism of action of HBOT for preserving compromised flaps is the possibility of closing arteriovenous shunts.

3- the same mechanisms of action that improve wound healing, namely, improved fibroblast and collagen synthesis and angiogenesis, also are likely to benefit a compromised graft or flap.

Success of a graft after HBOT multiple sessions

14. ACUTE THERMAL BURN INJURY

Thermal burns leads to

1- Marked inflammatory response with vascular derangement from activated platelets

2- White cell adhesion with resultant edema, hypoxia, and vulnerability to severe infection.

3- Poor white cell function caused by the local environment exacerbates this problem.

HBOT is begun as soon as possible after injury, with a goal of 3 treatments within the first 24 hours and then twice daily.

Length of treatment depends on the clinical impairment of the patient and the extent of and response to grafting

15. DIABAETIC FOOT AND FOOT ULCERS

16. IDIOPATHIC SUDDEN SENSORINEURAL HEARING LOSS

(New! approved on October 8, 2011 by the UHMS Board of

Directors

INDICATIONS APPROVED BY FDA

1. STROKE

1- HBO reduces chance of stroke recurrences2- HBO relieves muscle spasticity and increases muscle strength3- HBO improves mobility and fine motor function4- HBO improves walking and balance5- HBO increases exercise capacity6- HBO improves sensitivity7- HBO improves mental function including speech and memory8 - HBO improves visual acuity9- HBO improves bowel and bladder control and reduces sexual deficit

2. ISCHAEMIC HEART DISEASES

HBOT can do adequate oxygenation for heart muscle (myocardium) through plasma

incase of blockage of involved coronary artery

3. ALZHYMER’S DISEASE

4. MENIERE DISEASE

5. SPINAL CORD CONTUSIONS

6. MIGRAINE

7. NEAR DROWNING

8. RHEUMATIC ARTHRITIS

9.SPORTS INJURIES LIKE SPRAINS

10. Autism

SIDE EFFECTSMost common1- Middle ear barotraumas: can be prevented by excluding patients with URTI OR tympanostomy (Grommet tube) for child or infants PLUS equalization technique

2- or infants in need for multiple HBOT sessions and teaching patients the proper equalization technique

3- Lung: dry cough and chest pain

4- Dental : pain in decayed teeth

5- Oxygen toxicity: can be simply prevented by applying oxygen breathing 5 minutes break every 20 minutes

CONTRAINDICATIONSAbsolute :

only untreated tension pneumothorax.

Relative: Cardiac disease

Emphysema with CO2 retention Malignant disease: Cancers thrive in blood and oxygen rich

environments Pregnancy High fever

Upper respiratory tract infectionsAsthma and COPD

Convulsions and epilepsyPatients with pacemakers

ClaustrophobiaEustachian tube dysfunction

THANK YOU