3Function of ARTERIAL Fluids (Preservative) PreservationDisinfection -germicidal & bactericidalAnti-coagulationRestorationIt is important to achieve these without objectionable changes in skin and tissues.
4Action of Preservatives chemicals (or purpose for use) Inactivate active chemical groups of protein and/or amino acidsinhibit further decompositioninactivate enzymeskill microorganismsdestroy odors and eliminate their future production.
5Action of Preservatives chemicals PRESERVATIVE chemicals inhibit or arrest (retard) decompositionnot reverse
11Formaldehyde colorless gas has pungent, irritating odor strong dehydrating agentstrong oxidizing agentaccessory chemicals must be used to suppress the undesirable effects without loss of germicidal action
12Formaldehyde prepared or created by oxidation of alcohols specifically the burning of methanol
13Formaldehyde In aqueous solution is called formalin = HCHO gas dissolved in waterAlternately described as a solution and a mixture
14Formaldehyde = Formalin HCHO mixed with H2O is converted to methylene glycol (a mixture)Methylene glycol is an unstable compound (like hydrogen peroxide)
15Formaldehyde = Formalin Formalin is an aqueous solution of HCHOsaturated solution40% HCHO by volume 37% HCHO by weight
16Formaldehyde In embalming applications typically described by index Very little free formaldehyde is present in the aqueous solutionthat has little or no impact b/c the ability to preserve /disinfect is due to the donation of a methylene group CH2(= Methylene glycol)
17Formaldehyde In solid form known as PARAFORMALDEHYDE ParaHCHO is white powderWhen HCHO converts to solid (powder) the process is known as polymerization
18FormaldehydeMethanol is the anti-polymerant used to inhibit polymerization to para HCHO
19Formaldehyde Ammonia NH4OH is a good true deodorant for HCHO HCHO & nitrogen products have an affinity for one anotherwhen mixed the result isUROTROPIN
20polymerizes to PARAFORMALDEHYDE Ammonia NH4OH is a good true deodorant for HCHO ----> UROTROPINMethanol is the anti-polymerant used to inhibit polymerization to para HCHO***CONFUSION WARNING***Methanal is another name for HCHO
21Index amount of formaldehyde measured in grams IS:amount of formaldehydemeasured in gramsdissolved in 100 ml. of wateri.e. the % of HCHO gas in a fluid or solution
22Index measurements Strong / high ~33-40% HCHO (difficult cases) Medium / average ~20-30% HCHO (routine cases)Weak / low / mild ~10-18% HCHO (jaundice and special cases)
24General properties deep penetration i.e. total diffusion controlled firmingthorough preservationdehydration controlcontrolled pHuniform results(esp. when used with staining dyes)compatible with additives.
27Glutaraldehydepatented for use in embalming fluid in 1943, but really came to the attention of the industry in 1950'shas 2 functional aldehyde groups v. 1 for HCHO (di-aldehyde)is capable of reacting w/ protein over a wider pH range than other aldehyes
28has relatively low volatility, low odor, & low toxicity -is naturally a liquid is an effective cold chemical sterilant
29Glutaraldehyde v. HCHOmore effective as a disinfectant than HCHO (fixes protein rapidly)removes less water in the chemical reaction(so less of a dehydrating effect)disinfects quicker at lower concentrations than HCHOcreates more cross linkages than HCHO and the bonds are more stablehas better penetrating quality
30Q: So why hasn’t Glutaraldehyde replaced HCHO? A: more expensive than HCHO to produce
31Glyoxal More potent than HCHO (produces many more cross-links; the more links the firmer the tissue and the less flexible the protein)tends to stain tissue yellow so primarily used in cavity fluids;works best in ph of 9-10
32MOST PRESERVATIVES (especially HCHO) preserve best in an acid pH, BUT in acid pH environment:- the greatest dehydration takes place and- the greatest graying action takes placeAdvantage: dialdehydes
33Alcohols cross link protein, but not as effectively as aldehydes isopropyl has best germicidal qualitiesalcohols have strong dehydrating effect on proteinethanol, methanol, propanal, etc.methanol is good methylene group donor & anti polymerizing agent for aldehydes;is the most highly used alcohol
34Why use alcohols?1.outstanding preservative2. good solvent for chemicals that do not dissolve in water 3. excellent penetrator; some bleaching action 4. stabilizes HCHO 5. serves as vehicle for other ingredients in fluid 6. more toxic to bacteria than other alcohols
35PHENOLIC COMPOUNDS Phenol aka Carbolic Acid (C6H5OH) is a coal-tar derivativereliable disinfectantvery good penetrating action b/c it is very rapidly absorbed into protein structures of skin
36PHENOLbleaches tissues to a putty gray color (i.e., good for external packs on stains and discoloration)chiefly used in cavity formulationsdoes not produce the readily detectable firmness of aldehydestends to create putty gray when combined w/ aldehydes
37the most powerful phenolic compounds are not soluble in water found in triple or double base fluids with alcohol and/or HCHO(together these improve the bacteria killing power of phenols)
38Quaternary Ammonium Compounds (QUATS) good germicidal and deodorizing qualities used as topical antiseptic prior to surgeryin aqueous solution pH is neutralprimary embalming usecavity fluidscold sterilizationdeodorant spraysmold-proofing
39QUATERNARY AMMONIUM COMPOUNDS Disadvantages:not compatible with wetting & coloring agents in most arterialsany alkaline substance i.e. soap will render uselessused for disinfection of cavities, nose, skin, etc. but lose their capabilities in presence of HCHO
41Inorganic Salts potassium acetate sodium nitrate have been used since the early daysexamples:potassium acetatesodium nitratesome salts of Aluminum (Al)can also act as buffers, anticoagulants & water conditioners
42COMPONENTS OF ARTERIAL FLUIDS PreservativesGermicidesAnti-coagulantsVehiclesSurfactantsDyesReodorants/DeodorantsModifying agents
43Germicides Chemicals which kill disease causing microorganisms or render them incapable of reproduction(same list as for preservatives)
44Anti coagulantspostmortem processes naturally make blood become more viscousAnti-coagulants retard this tendency& / orprevent adverse reactions between blood and other embalming chemicals
45Anti coagulants are responsible to maintain blood in liquid state facilitate blood removalAnticoagulants may be the principal ingredients of co &/or pre-injection fluids
46Anti coagulantsOxalates & citrates were the original anticoagulants used but oxalates are toxic to the embalmerIonized calcium is a key factor in blood coagulation. calcium ions cause hard water therefore contributing to blood clotting & difficulties with drainage
47Vehicles aka solvent / diluent / carrier serve as a solvent for the many ingredients incorporated into an embalming fluid.Water*****Alcohol
48Vehiclesmay be a mixture of solvents which keeps the active ingredients in a stable and uniform state during transport thru the circulatory systemmust not react w/ the active components and make them uselessshould not react w/ the tissues of the circ. system, because this would interfere w/ distribution & diffusion.
49Water as chief vehicle composes more than half of formalin anyway vascular system is about 50% waterour bodies are 75-80% water.90% of our fluids use water as the vehicle.
50Alcohols as vehicles Methanol aka methyl alcohol / wood alcohol Ethanol aka ethyl alcohol – in some special purpose and cavity fluids.Glycerine, sorbitol, glycols
52Surfactantsreduce the molecular cohesion of a liquid and thereby enable the liquid to flow through smaller apertures (spaces)
53Advantages- promote diffusion of preservatives thru capillary walls for uniform saturation -promote uniform distribution of coloring agents -the lower the surface tension the faster the rate of penetration-increase the germicidal action of solution.
54Surfactants work best in low concentrations must be carefully selected for compatibility with other chemicalsMassage, manipulation and intermittent drainage aid the action of surfactants
56Dyes Staining (active) v. non-staining (inactive) Create cosmetic &/or non cosmetic fluidsMay be part of the fluid formulationOrAdded to the solution at discretion of embalmer
57examples Ponceau (cherry red – inactive) Carmine red (natural vegetable color)FuchsinErythrosineAmaranthEosine (yellow to orange)
58Reodorants/deodorants Chemicals having the capability of displacing or altering an unpleasant odor so that it is converted to a more pleasant onePerfuming materials / masking agentsPrimary function is to enhance odorsR is false D only – masks does not eliminate
59Reodorants/deodorants Most used in embalming are floral compounds which have been found to be most effective in mitigating odors.Intended to give a more pleasant odor, not to cover harshness of HCHO
60Examples Benzaldehyde Cloves Sassafras Oil of Wintergreen (is Methyl salicylate)Spices such as Lavender, rosemary, etc. (true low odor chemicals are result of using donor compounds for slow release of aldehyde, not due to use of re/deodorants
61Modifying agents Humectants Buffers Water conditioners (water softeners)
62Modifying agents Typically added to SOLUTION based upon case analysis purpose is to control the rate of action of the main preservative ingredientsGo to cavity fluids