Use of medical gases

Use of Medical Gases : 

Use of Medical Gases Definition of Medical Gas manufactured, packaged, and intended for administration to a patient in anesthesia, therapy, or diagnosis.

Slide 2: 

Medical Gases Air,Oxygen, Nitrogen, Nitrous oxide, Carbondioxide,Helium,Xenon 1 atmosphere = 760 mm Hg = 760 torr = 101.3 kPa=14.5 psi=1030 cm of H2O=1000 milli bar

Slide 5: 

Kinetic Molecular Model of Water At 100°C, water becomes water vapor, a gas. Molecules can move randomly over large distances. Below 0°C, water solidifies to become ice. In the solid state, water molecules are held together in a rigid structure. Between 0°C and 100 °C, water is a liquid. In the liquid state, water molecules are close together, but can move about freely.

Slide 9: 

To change to liters, multiply the cubic feet by 28.33.

Cylinder measurements : 

Cylinder measurements flattening, bend , impact tests (1 in 100), pressure tests and tensile tests (1 in 100).

DOT-3AL 2015 ASXXXXXXX O2 CLIFFDIV 07C08 TC-3ALM139Cylinder crown markings : 

DOT-3AL 2015 ASXXXXXXX O2 CLIFFDIV 07C08 TC-3ALM139Cylinder crown markings Regulatory authority( DOT) cylinder manufacturing specification Service pressure in PSI cylinder serial no Manufactures no Original hydrostatic test date month followed by year including symbol of inspection agency Name of Manufacturer of cylinder Cylinder identifier – eg-M24-medical 2 cft Cylinder outlet threaddesignation symbol of the filled gas (O2) and that the lot of cylinders was subjected to hydrocarbon testing The canadian regulatory authority symbol TC and specification 3ALM to which the cylinder is made. The service pressure in bars

Slide 13: 

D = 350 liters,415 E = 625,682 M = 3,000,1723G= 5,300, H = 6,900.

Aluminium Oxygen cylinders : 

Aluminium Oxygen cylinders

Slide 18: 

The Calculations of How Long the Oxygen Content of the Size E Cylinder (680 L) Will Last for a Given Flow Rate Anesth Analg 2004;99:307-308

Slide 19: 

"E" Cylinder - 682 Litres - 29" High x 4" Diameter - 6.8 kgs Empty Weight

Slide 20: 

How do you estimate how much is in a cylinder of N20? 1 mole of N20 occupies 22.4 litres at standard temperature and pressure. The molecular weight of N20 is 44. If the cylinder contains 2.5 kg (2500 g) of N20, then you can calculate the volume of gas by dividing the weight by the molecular weight and multiplying it by 22.4: 2500/44 x 22.4 = 1272 Litres.

Slide 26: 

ANTI CLOCKWISE is OPEN/ON and CLOCKWISE is CLOSED/OFF

Medical Air –Specifications & Uses : 

Medical Air –Specifications & Uses Should be free from toxic products, flammable or toxic vapours, and odours at all points in the pipeline system. Although it is not sterile medical grade air is clean and at STP should not contain more than: 0.5mg of particulate oil mist /cm3 5.5mg of carbon monoxide/ cm3 900 mg carbon dioxide/ cm3 no moisture no bacterial contamination as a replacement for atmospheric air in anaesthesia as a carrier gas for volatile anaesthetic agents as a power source for pneumatic equipment ventilators and incubators to provide uncontaminated and controlled air flows

Slide 31: 

process of declining oxygen tension from atmosphere to mitochondria. [1.34 x Hb x (SaO2/100)] + 0.003 x PO2 = 20.8mlFor each mmHg of PO2 there is 0.003 ml O2/dl (100ml of blood)

Slide 32: 

Medical Oxygen Oxygen is an essential ingredient for aerobic life. Medical Oxygen is used to restore the tissue oxygen tension towards normal by improving oxygen availability in Cardiac and respiratory arrest; Resuscitation of critically ill when circulation is impaired Cyanosis of recent origin as a result of cardio-pulmonary disease Surgical trauma, chest wounds and rib fractures Hyperpyrexia Carbon Monoxide poisoning Shock, severe haemorrhage and coronary occlusion Modern anaesthesia techniques as well as pre and post operative management Neonatal resuscitation

Slide 33: 

What are the benefits of Oxygen? To prolong life in persistent hypoxaemia To reduce comorbidity in persistent hypoxaemia To improve exercise performance To reduce breathlessness acutely

Slide 34: 

Aims of oxygen therapy to increase PaO2 to acceptable level with concentration of oxygen to decrease respiratory rate and work of breathing Hypoxaemia with high PaCO2 24% initially careful monitoring with regular ABG’s

Slide 35: 

The quick-flush should not be operated when a Bain circuit is in use, since the blast of high-pressure gas is directed down the endotracheal tube and may cause pulmonary barotraouma.

Slide 38: 

Nasal cannula: flow rate 1-6 LPM, 24-44 percent oxygen concentration, breathing victims only Resuscitation mask: flow rate 6 -15 LPM, 35-55 percent oxygen concentration, breathing and non-breathing victims Non-rebreather mask: flow rate 10-15 LPM, 90+ percent oxygen concentration, breathing victims only BVM: flow rate 15 LPM or more, 90+ percent oxygen concentration, breathing and non-breathing victims

Slide 45: 

Hyperbaric Oxygen therapy Air or gas embolism   Carbon monoxide poisoning  Carbon monoxide poisoning complicated by cyanide poisoning    Claustridial myositis and myonecrosis (gas gangrene)    Crush injury, compartment syndrome and other acute traumatic ischaemias    Decompression sickness    Enhancement of healing in selected problem wounds    Exceptional blood loss (anaemia)    Intracranial abscess    Necrotising soft tissue infections    Osteomyelitis (refractory)    Delayed radiation injury (soft tissue and bony necrosis)    Skin grafts and flaps (compromised)    Thermal burns

Slide 47: 

650nm 660 nm 800 nm 940 nm wavelength A wavelength B Red Infrared . OxyHb DeoxyHb Isobestic points. Absorbance

Slide 48: 

Oxygen Therapy-side effects : 

Oxygen Therapy-side effects Drying of nasal and pharyngeal mucosa   Substernal Pain Hypoventilation (COAD) Atelectasis Pulmonary damage and oedema Retrolental fibroplasia

Choice of correct inspired concentration ofOxygen (FiO2) : 

Choice of correct inspired concentration ofOxygen (FiO2) Those with normal respiratory control Those with abnormal respiratory control Oxygen  prescription Target  saturations  94‐98% →  most  acutely  ill   88‐92%→  at  risk  of  hypercapnic  respiratory  failure

Slide 51: 

Oxygen  prescription Target  saturations  94‐98% →  most  acutely  ill   88‐92%→  at  risk  of  hypercapnic  respiratory  failure

Gas Mixtures : 

Gas Mixtures Gas of a lesser density can more easily bypass an obstruction and therefore be inspired further with less effort and resistance. Entonox Heliox Carbogen

Gas flow : 

Gas flow

Heliox : 

Heliox

Entonox(50:50) : 

Entonox(50:50) Entonox related side effects include Earache Dry mouth Dizziness or disorientation Over sedation Nausea & vomiting Entonox should be self administrated when used for procedural pain

Entonox—Contraindi… : 

Entonox—Contraindi… artificial, traumatic or spontaneous pneumothorax. intestinal obstruction. head injuries with impaired consciousness. severe bullous emphysema. Maxillo facial injuries. intoxication. following air encephalography. decompression sickness. air embolism. middle ear occlusion.