Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
  • A61M16/10—Preparation of respiratory gases or vapours
  • A61M16/104—Preparation of respiratory gases or vapours specially adapted for anaesthetics
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B21/00—Nitrogen; Compounds thereof
  • C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
  • C01B21/22—Nitrous oxide (N2O)
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B21/00—Nitrogen; Compounds thereof
  • C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
  • C01B21/24—Nitric oxide (NO)
  • C01B21/26—Preparation by catalytic or non-catalytic oxidation of ammonia
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C13/00—Details of vessels or of the filling or discharging of vessels

Definitions

• Oxygen is one of the so-called permanent gases, that is to say, it remains in the gas phase at ambient temperatures whatever the pressure.
• the pressure in an oxygen cylinder progressively falls ,as the contents are used and does not vary much with the ambient temperature.
• a pressure gauge can therefore, serve as a simple contents indicator.
• nitrous oxide can be and usually the present invention.
• the cylinders are designed for such duty and it is uneconomic to use them for the storage and transport of gases at considerably lower pressures;
• a method of forming ahomogeneous mixture of a permanenfgas, and ,up to 75% of nitrous oxide comprises charging the gases in the predetermined required proportions into a pressure container until a pressure is'reached at which the partial is stored under pressure in the liquid phase. Under static 7 effect on pressure. No simple means for determining the contents of a nitrous oxide cylinder under normal conditions of use is available and there is therefore a danger that the supply of nitrous oxide will-run out unexpectedly.
• the mixture iscompressed to at. least 132 atmospheres.
• a homogeneous gaseous medium comprising up to 75% nitrous oxide in admixture with a permanent 'gas confined in a container at a pressure such that the oxide is greater than.50.atmospartial pressure of nitrous oxide is greater than 50 atmospheres.
• the permanent gas most commonly used with nitrous oxide is oxygen.
• a nitrous oxide/ oxygen mixture containing nitrous oxide in the range of 50 to 60% is frequently administered.
• a more potent drug such as halothane or cyclopropane may be added as a constituent of the nitrous oxide/oxygen mixture.
• halothane halothane
• cyclopropane may be included in the nitrous oxide/ oxygen mixture as the potent adjuvant, while maintaining the contents of the pressure container entirely in-the gaseous phase.
• the mixture may be inflammable and the usual precautions should be taken to guard against risk of static discharge.
• the required proportion of nitrous oxide is preferably charged into a valved pressure container first, the quantity being determined either by weight or by volume.
• the required'proportionof permanent gas then added, either continuously or intermittently so as to allow equilibrium to take place.
• the attainment of equilibrium namely the complete disappearance of the liquid phase, may be accelerated by agitating the contents.
• the container may be shaken during charging with oxygen,
• the container may be rolled about after charging.
• the container may be inverted so that the. oxygen bubbles through the liquid nitrous oxide.
• the nitrous oxide and oxygen are charged simultaneously into the container.
• the two gases are preferably premixed, either in a gas holder from which they are pumped into the container, or continuously by the method known as streaming in in which the flow rates of the separate gas streams are adjusted to produce the correct mixture.
• the invention may be illustrated by the following example.
• a standard'compressed gas cylinder was used having a nominal compressed gas capacity of 220 cu. ft. at 132 atmospheres pressure.
• a weighed amount of nitrous oxide was charged into the cylinder, following which oxygen was introduced until the pressure reached 135 atmospheres.
• the composition of the mixture was found on analysis to be 74.9 of nitrous oxide and 25.1% of oxygen.
• the cylinder was allowed to discharge, and at intervals samples of the issuing gas were taken from the cylinder in its normal upright position and in the inverted position.
• the nitrous oxide content of the samples was determined by measurement of the difference between the refractive index of the gas mixture and that of oxygen. The results obtained which are subject to an error of i0.2% were as follows: 1
• nitrous oxide with-permanent gases other than oxygen can be prepared in a manner. similar to that described above to yield a mixture of constant composition, evenif the partial, pressure of nitrous oxide isin excess of 50 ats.
• a specific example of such amixture is a nitrous oxide/nitrogen mixture containing up to 75% nitrous oxide in a pressure container to 132 ats.
• Such mixtures are of use in leak detection, using infra red apparatus where it is necessary for the test procedure to be conducted at relatively high pressure. Such high pressure testing is sometimes necessary for detecting leaks in water mains and other hydraulic equipment such as tubular condensers.
• the method of forming a homogeneous mixture of a permanent gas .and nitrous oxide which comprises charging the nitrous oxide into a valved pressure container, subsequently charging into the same container a permanent gas so that the subsequent mixture includes from 15 up to 75% by volume of nitrous oxide,and until a final pressure is reached at which the partial'pressure of nitrous oxide is greater than 50 ats.
• the method of forming a homogeneousmixture of a permanent gas and of nitrous oxide which comprises charging the gases in proportions of from 15% up to 75% by volume of the nitrous oxide into a pressure container until a final pressure is reached at which the partial pressure of nitrous oxide is greater than 50 ats.
• the method of forming a homogeneous mixture of oxygen and nitrous oxide which comprises charging the gases in proportions of from 15% up to 75% volume of the nitrous oxide into a pressure container until a final pressure is reached at which the partial pressure of nitrous oxide is-greater than 50 ats.
• a pressurized dispensing container Within which is a homogeneous gaseous medium comprising from 15% up to 75% by volume of nitrous oxide in admixture with a permanent gas, the partial pressure of nitrous oxide being greater than 50 ats.
• a pressurized dispensing container within which is a homogeneous gaseous medium comprising up to 75% by volume of nitrous oxide in admixture with oxygen, the partial pressure of nitrous oxide being greater than SO ats.
• a pressurized dispensing container within which is a homogeneous gaseous medium comprising from 15% up to 75 by volume of nitrous oxide in admixture with oxygen and from a trace up 1% by volume of halothane, the partial pressure of nitrous oxide being greater than 50 ats.
• a pressurized dispensing container within which is a homogeneous gaseous medium comprising from 15 up to 75% by volume of nitrous oxide in admixture with oxygen and from a trace up to 5% by volume of cyclopropane, the partial pressure of nitrous oxide being greater than 50 ats.
• a pressurized dispensing container within which is a homogeneous gaseous medium comprising from 15% up to 75% by volume of nitrous oxide in admixture with nitrogen, the partial pressure of nitrous oxide being greater than ats.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Emergency Medicine (AREA)
• Inorganic Chemistry (AREA)
• Anesthesiology (AREA)
• Hematology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Pulmonology (AREA)
• Mechanical Engineering (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• General Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
• Filling Or Discharging Of Gas Storage Vessels (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=10291248

Family Applications (1)

Country Status (5)

Cited By (20)

Citations (1)

• 0
  • BE BE660318D patent/BE660318A/xx unknown
• 1961
  • 1961-08-15 GB GB29417/61A patent/GB967930A/en not_active Expired
• 1962
  • 1962-08-13 DE DEB68400A patent/DE1183051B/de active Pending
  • 1962-08-13 US US216301A patent/US3192106A/en not_active Expired - Lifetime
  • 1962-08-13 FR FR906854A patent/FR1511552A/fr not_active Expired

Patent Citations (1)

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