Properties and systemic effects of nitrous oxide
Effects of nitrous oxide in various systems of the body
CNS depressant action, though there is limited analgesia. Amnesia is possible only at higher concentration.
Reduces CO2 stimulated respiratory drive therefore problems may result if used in combination with narcotics.
Decreases cardiac output and increases peripheral vascular resistance. This is significant in patients suffering from cardiac problems.
Vomiting may be induced depending on the length of exposure and concentration of the drugs.
Toxic effects:
Depression of bone marrow after prolong use.
On long term exposure to high ambient levels of gas, the personal using the gas for sedation may have serious complications like spontaneous abortions, increase in hepatic diseases, etc.
Properties of ideal nitrous oxide anaesthesia
For the patient
It should be pleasant, non irritating, should not cause nausea or vomiting. Induction and recovery should be fast with no after effect.
For the surgeon
It should provide adequate analgesia, immobility and muscle relaxant.
It should be noninflammable and nonexplosive so that cautery may be used.
For the anaesthetics
Its administration should be easy, controllable and versatile.
Margin of the safety should be wide, no fall in BP.
Heart, liver and others organs should not be affected.
It should be potent so that low concentrations are needed and oxygenation of the patient does not suffer.
Rapid adjustment in depth of anaesthesia should be possible.
It should be cheap, stable and easily stored.
It should not react with rubber tubing or soda lime.
Physical & anaesthetic properties table:
| Anaesthetic | Nitrous oxide |
| Boiling point (ºc) | Gas |
| Inflammability | Noninflammable |
| Irritancy (odor) | - |
| Oil | Gas Partition |
| Coefficient | 1.4 |
| Blood: | Gas Partition |
| Coefficient | 0.47 |
| MAC (%) | 105 |
| Induction | Fast |
| Muscle relaxation | Poor |
Related Links:
Effects of nitrous oxide in various systems of the body
