Embalming Theory and Practice
Aims and sequence
The four aims are sanitation, preservation, restoration and presentation. A safe, logical sequence is: position and assess the body, disinfect, set the features, select and raise the vessel, inject arterially while draining, treat the cavities, use hypodermic injection where needed, restore, then make a final check and record what you did.
Fluids and dilution
Formaldehyde is the primary preservative; the index is the percentage of formaldehyde in the concentrate. Dilution is the examinable core: volume of concentrate multiplied by its index, divided by the final volume, gives the working index.
Worked example: 2 litres of 20-index fluid made up to 8 litres. 2 × 20 = 40; 40 ÷ 8 = 5, so the working solution is 5-index.
Know the factors affecting distribution and drainage: vessel choice, injection pressure and rate, restrictions such as thrombosis or calcification, oedema, obesity and gas-forming infection. Understand when to modify practice for jaundice, oedema, dehydration, trauma, autopsy cases and infectious disease.
Traps
Confusing index with concentration; assuming more fluid is always better; forgetting that drainage must be managed, not ignored; and treating oedema as if it were dehydration.
Rule of thumb
Calculate before you mix, and write the calculation down. If the result looks stronger than the case needs, it probably is; strong is not the same as good.