LIGATURE AND SUTURE MATERIALS 1
Surgical procedures require superficial tissue layers to be cut, to reach the required Organ.
-On closure at the end of the procedure, all these cut layers, must be stitched back in position, accurately to its opposing layer.
-Anatomical continuity, interrupted while opening up the body needs to be restored.
WHAT ARE THE SUTURES AND LIGATURES IN USE?
Surgeons have made use of sutures for achieving closure.
The following are some available techniques for skin closure.
1. Needle and suture
2. Skin clips
3. Staples
4. Adhesive closure
SUTURE
A suture or a stitch holds cut tissue layers, or structure
Together, this helps the process of healing.
LIGATURE
A ligature, or metal ligature, is the use of the material, to
Encircle a cut end of a blood vessel, so as to control bleeding.
Staples have been used to anastomose(join) hollow organs, and vassal
Suture can be:-
1 Absorbable or
2 Nonabsorbable
And both these varieties may be made of either natural or
synthetic fibre have to be used with a needle.
WHAT ARE THE NEEDLES AVAILABLE?
These are pointed metal instruments with an eye where thread has to be passed through so that two strands pass through the tissues causing little trauma.
* The same is true of sprng eye needles Fig.3.4
* Shapes of needles are shown in fig. and vary from quarter circle
to straight and the shape of the tip of the needle Fig.3.1A to D
* Atraumitic needle come with the suture materiel (single
strand) attached to the needle fig.3.2
These are pre-sterilized and come in double wraps. Fig 3.3
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
Friday, September 24, 2010
Saturday, September 18, 2010
DISPOSABLES & INCINERATION
CAN YOU ACHIEVE STERILIZATION BY IONIZING RADIATION?
Most equipment, available prepackaged from the manufacturer, has been sterilized by ionizing radiation, Items such as
sutures,
sponges,
and disposable drapes, are just a few of the many types of presterilized products available. Included are anhydrous materials such as powders and petroleum goods.
NEW METHODS STERILIZATION BY LOW-TEMPERATURE STEAM AND FORMALDEHYDE (LTSF)
This is a physicochemical method which uses a combination of dry saturated steam and formaldehyde to kill vegetative bacteria, bacterial spores and most viruses and the method is thus suitable for heat-sensitive materials and items of equipment with intergal plastic components susceptible to damage by other processes.
Prior to removal of sterilized objects all formaldehyde must be removed to provide a dry, sterile, formalin-free load.
DISPOSE USED CONTAMINATED MATERIAL BY INCINERATION
This is the preferred method of disposal for all combustible and other material of an infectious nature .
contaminated needles,
plastic syringes and
clinical waste.
Disposable linen, and infected protective clothing, and drapes, should be by incinerated.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
Most equipment, available prepackaged from the manufacturer, has been sterilized by ionizing radiation, Items such as
sutures,
sponges,
and disposable drapes, are just a few of the many types of presterilized products available. Included are anhydrous materials such as powders and petroleum goods.
NEW METHODS STERILIZATION BY LOW-TEMPERATURE STEAM AND FORMALDEHYDE (LTSF)
This is a physicochemical method which uses a combination of dry saturated steam and formaldehyde to kill vegetative bacteria, bacterial spores and most viruses and the method is thus suitable for heat-sensitive materials and items of equipment with intergal plastic components susceptible to damage by other processes.
Prior to removal of sterilized objects all formaldehyde must be removed to provide a dry, sterile, formalin-free load.
DISPOSE USED CONTAMINATED MATERIAL BY INCINERATION
This is the preferred method of disposal for all combustible and other material of an infectious nature .
contaminated needles,
plastic syringes and
clinical waste.
Disposable linen, and infected protective clothing, and drapes, should be by incinerated.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
Friday, September 10, 2010
VIRUS IN THE OT
OT accidents 2
WHAT IS HIV INFECTION?
THE VIRUS
The acquired immune deficiency syndrome (AIDS) was first described in 1981 and the human immunodeficiency virus (HIV) was first identified in 1983.
- Antibody tests were developed which revealed the HIV status of the individual.
- In 1986 a second strain, HIV 2, was isolated
.
- Like hepatitis B, the virus is present in blood and body fluids, but unlike hepatitis B is relatively easily destroyed outside the body, and is not as infectious as the hepatitis B virus.
- Infection of the surgeon can occur from contamination from infected blood or body fluids, either through an open wound, or from a puncture wound like a needle-stick injury.
- Following infection there is an asymptomatic period during which antibody to the virus is not yet present in the blood, and thus HIV tests will be negative.
- After approximately 6 months the infected individual may seroconvert, and the HIV antibody be detected.
- A high proportion will then progress to develop AIDS.
LOOK FOR
- A common presenting feature is AIDS sufferers is the Kaposi sarcoma, with an incidence of between 25%and 50%. Biopsy of such lesions may be the first indicator for the surgeon that the patient has this disease.
- Kaposi sarcomas present as pink to purple blotches like a bruise or blood blister.
They may be flat or raised.
They are skin cancer arising from the endothelial cells such as those lining blood vessels. Histological, malignant transformation causes the endothelial cells to become stippled with spindle-shaped tumor cells; lymphatic obstruction may occur, but they do not metastasize, and remain multimodal both on the skin and in the alimentary tract.
SURGEON’S RISK.
Despite the worry of surgeons about risks of infection, these risks are small.
- The prevalence rate of HIV 0.3-7% in our country.
Surgeons have been shown to contaminate themselves with blood in 8.7% cases, and sustain penetrating injuries in 1.7% cases
The transmission rate is 0.3-0.4%, yet statistically the risk of sero-conversion for a surgeon is one infection every 8 years in a high-risk area with a case-load of 15000 patients per year.
As small as one infection every 80 years, in a low risk area.
Thus the risk to surgeon at work, is exceptionally low
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
WHAT IS HIV INFECTION?
THE VIRUS
The acquired immune deficiency syndrome (AIDS) was first described in 1981 and the human immunodeficiency virus (HIV) was first identified in 1983.
- Antibody tests were developed which revealed the HIV status of the individual.
- In 1986 a second strain, HIV 2, was isolated
.
- Like hepatitis B, the virus is present in blood and body fluids, but unlike hepatitis B is relatively easily destroyed outside the body, and is not as infectious as the hepatitis B virus.
- Infection of the surgeon can occur from contamination from infected blood or body fluids, either through an open wound, or from a puncture wound like a needle-stick injury.
- Following infection there is an asymptomatic period during which antibody to the virus is not yet present in the blood, and thus HIV tests will be negative.
- After approximately 6 months the infected individual may seroconvert, and the HIV antibody be detected.
- A high proportion will then progress to develop AIDS.
LOOK FOR
- A common presenting feature is AIDS sufferers is the Kaposi sarcoma, with an incidence of between 25%and 50%. Biopsy of such lesions may be the first indicator for the surgeon that the patient has this disease.
- Kaposi sarcomas present as pink to purple blotches like a bruise or blood blister.
They may be flat or raised.
They are skin cancer arising from the endothelial cells such as those lining blood vessels. Histological, malignant transformation causes the endothelial cells to become stippled with spindle-shaped tumor cells; lymphatic obstruction may occur, but they do not metastasize, and remain multimodal both on the skin and in the alimentary tract.
SURGEON’S RISK.
Despite the worry of surgeons about risks of infection, these risks are small.
- The prevalence rate of HIV 0.3-7% in our country.
Surgeons have been shown to contaminate themselves with blood in 8.7% cases, and sustain penetrating injuries in 1.7% cases
The transmission rate is 0.3-0.4%, yet statistically the risk of sero-conversion for a surgeon is one infection every 8 years in a high-risk area with a case-load of 15000 patients per year.
As small as one infection every 80 years, in a low risk area.
Thus the risk to surgeon at work, is exceptionally low
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
Friday, September 3, 2010
THE NEW VIRUS IN OT
OT ACCIDENTS
WHAT IS HEPATITIS B (SERUM HEPATITIS)?
How does it occur in OT?
This is one of the most infective viruses.
- It may be transmitted from patient to patient by as little as 0.0001 ml. of infected blood.
- The virus remains active, for up to 6 months in dried blood, consequently instruments which have been poorly cleaned or disinfected, may be responsible for infecting other patients, whilst poor surgical technique, may result in the doctor becoming infected from the patient, or vice versa thru a needle prick.
- It has been estimated that there are possibly 200 million carriers of hepatitis in the world, representing up to 20% of the population in African, Pacific, and other tropical countries, and 0.5% of the population in Northern Europe. The current prevalence in the population is from 1-15.8%
- Thus, statistically the doctor or nurse has a 1 in 200 chance of treating a hepatitis B carrier.
- If the doctor becomes accidentally infected with the hepatitis B virus, not only may the disease develop, but the doctor may become a hepatitis B carrier, and is an unacceptable risk to patients and may have to give up surgery.
The transmission role in case of needle stick is 6 to 37%.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review.
WHAT IS HEPATITIS B (SERUM HEPATITIS)?
How does it occur in OT?
This is one of the most infective viruses.
- It may be transmitted from patient to patient by as little as 0.0001 ml. of infected blood.
- The virus remains active, for up to 6 months in dried blood, consequently instruments which have been poorly cleaned or disinfected, may be responsible for infecting other patients, whilst poor surgical technique, may result in the doctor becoming infected from the patient, or vice versa thru a needle prick.
- It has been estimated that there are possibly 200 million carriers of hepatitis in the world, representing up to 20% of the population in African, Pacific, and other tropical countries, and 0.5% of the population in Northern Europe. The current prevalence in the population is from 1-15.8%
- Thus, statistically the doctor or nurse has a 1 in 200 chance of treating a hepatitis B carrier.
- If the doctor becomes accidentally infected with the hepatitis B virus, not only may the disease develop, but the doctor may become a hepatitis B carrier, and is an unacceptable risk to patients and may have to give up surgery.
The transmission role in case of needle stick is 6 to 37%.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review.
Friday, August 20, 2010
STERILIZATION 4
STERILIZERS AND CONFIRM SUCCESS
WHAT ARE THE TYPES?
GRAVITY DISPLACEMENT STERILIZER The gravity (or "downward") displacement sterilizer uses the principle that air is heavier than steam.
-Within the sterilizer there is an inner chamber where goods are loaded and an outer jacket type chamber that injects steam forcefully into it.
-Any air in the inner chamber blocks the passage of pressureized steam to the surface of the goods and thus prevents sterilization.
-All the air must be removed because every surface of the supplies must be exposed to the pressurized steam to ensure sterilization.
-Therefore, the sterilizer is constructed in such a way that air is pushed downward by gravity (hence the name "gravity displacement sterilizer").
PRE-VACUUM STERILIZER The pre-vacuum sterilizer does not rely on gravity to remove air from the inner chamber. Instead, the air is pulled out of the chamber, which creates a vacuum in the chamber.
Steam is injected into the chamber to replace the air. This type of sterilizer offers greater steam penetration in a shorter time than the gravity displacement sterilizer.
FLASH STERILIZER The flash sterilizer has traditionally been used in the operating room and in other areas of the hospital to quickly sterilize items that are unwrapped.
It has been common practice to flash sterilize any instrument that had become contaminated during surgery.
HOW DO CONFIRM STERILIZATION?
- A chemical monitor is an object that is treated with material that changes its characteristics when sterilized.
This may be in the form of special ink that is impregnated into paper strips or tape and placed on the outside of the package, or it may be a substance that is incorporated into a pellet contained in a glass vial.
- The chemical responds to conditions such as extreme heat, pressure, or humidity but does not take into consideration the duration of exposure, which is critical to the sterilization process.
- Another monitoring method used to evaluate the steam sterilizer is the combined temperature time graphs that are installed within the control panel of the sterilizer. These graphs provide a permanent written record of all loads that have been processed.
- The surest way, to determine the sterility of given item, is with the use of biologic controls.
A highly resistant, nonpathogenic, spore-forming bacteria, is used as indicator. Contained in a glass vial or a strip of paper.
This is placed in the load of goods, to be sterilized.
For steam sterilization, the dry spores of the bacteria Bacillus Stearothermophilus are used.
The gas sterilization process uses the bacterium Bacillus Subtilis.
The vial or strip is recovered at the end of the sterilization process and cultured.
This process is time consuming and the results method of testing the efficacy of a sterilization process. Biologic controls should be administered at least once weekly. If feasible, they should also be used whenever an artificial implant or prosthesis is sterilized and the item withheld from use until the results are known to be negative.
ANY questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
WHAT ARE THE TYPES?
GRAVITY DISPLACEMENT STERILIZER The gravity (or "downward") displacement sterilizer uses the principle that air is heavier than steam.
-Within the sterilizer there is an inner chamber where goods are loaded and an outer jacket type chamber that injects steam forcefully into it.
-Any air in the inner chamber blocks the passage of pressureized steam to the surface of the goods and thus prevents sterilization.
-All the air must be removed because every surface of the supplies must be exposed to the pressurized steam to ensure sterilization.
-Therefore, the sterilizer is constructed in such a way that air is pushed downward by gravity (hence the name "gravity displacement sterilizer").
PRE-VACUUM STERILIZER The pre-vacuum sterilizer does not rely on gravity to remove air from the inner chamber. Instead, the air is pulled out of the chamber, which creates a vacuum in the chamber.
Steam is injected into the chamber to replace the air. This type of sterilizer offers greater steam penetration in a shorter time than the gravity displacement sterilizer.
FLASH STERILIZER The flash sterilizer has traditionally been used in the operating room and in other areas of the hospital to quickly sterilize items that are unwrapped.
It has been common practice to flash sterilize any instrument that had become contaminated during surgery.
HOW DO CONFIRM STERILIZATION?
- A chemical monitor is an object that is treated with material that changes its characteristics when sterilized.
This may be in the form of special ink that is impregnated into paper strips or tape and placed on the outside of the package, or it may be a substance that is incorporated into a pellet contained in a glass vial.
- The chemical responds to conditions such as extreme heat, pressure, or humidity but does not take into consideration the duration of exposure, which is critical to the sterilization process.
- Another monitoring method used to evaluate the steam sterilizer is the combined temperature time graphs that are installed within the control panel of the sterilizer. These graphs provide a permanent written record of all loads that have been processed.
- The surest way, to determine the sterility of given item, is with the use of biologic controls.
A highly resistant, nonpathogenic, spore-forming bacteria, is used as indicator. Contained in a glass vial or a strip of paper.
This is placed in the load of goods, to be sterilized.
For steam sterilization, the dry spores of the bacteria Bacillus Stearothermophilus are used.
The gas sterilization process uses the bacterium Bacillus Subtilis.
The vial or strip is recovered at the end of the sterilization process and cultured.
This process is time consuming and the results method of testing the efficacy of a sterilization process. Biologic controls should be administered at least once weekly. If feasible, they should also be used whenever an artificial implant or prosthesis is sterilized and the item withheld from use until the results are known to be negative.
ANY questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for access and review
METHODS OF STERILIZATION 3
CHOICE of GOOD AUTOCLAVE & CYCLE
- A`quick' cycle would heat the water to 134 degree C (273 degree F) for 3.5 min. under a pressure of 30 1b/sq in.
- Slower cycle, more suitable for plastics, would heat the water to 121 degree C under a pressure of 15 1b/sq in 15 minutes.
- In practice, instruments are placed in the trays or in packs, the autoclave turned on, and left for the desired time.
- At the end of the cycle, the instruments are ready for use.
-They will be dry with vacuum and air outlet.
The main disadvantage of the smaller autoclave is that instrument packs cannot be sterilized as there is not a vacuum cycle to extract air and dry the packs.
However, most materials including rubber, plastics and metal can be readily sterilized, the only exception being sealed containers.
Steam is the gaseous form of water. If it is to sterilize effectively, by killing all spores:
- It must be at an appropriate temperature (which implies an appropriate pressure).
- It the chamber must be saturated with STEAM.
- Thus not be mixed with air, so it must displace all the air in the chamber of the autoclave.
- And, it must reach all parts of the load. If it contains droplets of water, it will soak into porous materials.
If no air is discharged, the bottom of the chamber may be much cooler, than the top.
As soon as the chamber of an autoclave is full of steam, at the desired temperature, and pressure, it must be held there, for a critical time-the holding time.
The standard holding time is 15 minutes, at 121 degree C, but you may need to vary it.
Single walled autoclaves are strong metal chambers with water in the bottom, like large pressure cookers. They have several disadvantages and may not be acceptable foe hospital use..
A good autoclave (with double wall & vacuum) is by far the most efficient method of sterilization for materials that will stand up to heat and moisture.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for your access and review
- A`quick' cycle would heat the water to 134 degree C (273 degree F) for 3.5 min. under a pressure of 30 1b/sq in.
- Slower cycle, more suitable for plastics, would heat the water to 121 degree C under a pressure of 15 1b/sq in 15 minutes.
- In practice, instruments are placed in the trays or in packs, the autoclave turned on, and left for the desired time.
- At the end of the cycle, the instruments are ready for use.
-They will be dry with vacuum and air outlet.
The main disadvantage of the smaller autoclave is that instrument packs cannot be sterilized as there is not a vacuum cycle to extract air and dry the packs.
However, most materials including rubber, plastics and metal can be readily sterilized, the only exception being sealed containers.
Steam is the gaseous form of water. If it is to sterilize effectively, by killing all spores:
- It must be at an appropriate temperature (which implies an appropriate pressure).
- It the chamber must be saturated with STEAM.
- Thus not be mixed with air, so it must displace all the air in the chamber of the autoclave.
- And, it must reach all parts of the load. If it contains droplets of water, it will soak into porous materials.
If no air is discharged, the bottom of the chamber may be much cooler, than the top.
As soon as the chamber of an autoclave is full of steam, at the desired temperature, and pressure, it must be held there, for a critical time-the holding time.
The standard holding time is 15 minutes, at 121 degree C, but you may need to vary it.
Single walled autoclaves are strong metal chambers with water in the bottom, like large pressure cookers. They have several disadvantages and may not be acceptable foe hospital use..
A good autoclave (with double wall & vacuum) is by far the most efficient method of sterilization for materials that will stand up to heat and moisture.
Any questions be sent to drmmkapur@gmail.com
All earlier posts are stored in archives for your access and review
Friday, August 6, 2010
METHODS OF STERILIZATION 2
STERILIZATION BY HOT-AIR OVENS:
These are thermostatic controlled ovens, with an electric heating element, similar to a domestic electric oven.
- Instruments to be sterilized are heated to 160 degree C (320 degree F) for 1 hour.
- Sterilization is achieved, but it is not suitable for rubber or plastic instruments.
- In hospital has been used for sterilizing powders and petroleum products and sharp delicate instruments
The efficiency of dry heat sterilization depends on the initial moisture of the microbial cells, but all microorganisms are killed at 160 degree C for a hold time of not less than 2 hours.
The main advantages of dry heat sterilization are its ability to treat solids, non-aqueous liquids, grease/ointments and to process closed (airtight) containers.
Lack of corrosion is important in the sterilization of non-stainless metals and surgical instruments with fine cutting edges.
WHAT ARE AUTOCLAVES?
This is the most efficient method of sterilizing instruments, packs and dressings, and is suitable for most materials.
An autoclave is basically a pressure cooker and in fact, there is no reason why a domestic pressure cooker should not be used to sterilize instruments in a small clinic.
The small autoclaves produced for the doctor's surgery offer a choice of temperatures, pressures and sterilizing times:
The highest temperature that can be reached by boiling water at sea level in an open vessel is 100 degree C.
With increased pressure, the water can be raised to much higher temperatures before it boils, e.g., at a pressure of 0.35 kg per cm2 (5 p.s.i.) the temperature reaches 105.5 degree C: at 0.7 kg per cm2 (10 p.s.i.). 115 degree C; and at 1.05 kg per cm2 (15 p.s.i.) the temperature will reach 121 degree C, etc. In a sterilizer chamber (autoclave) which has been well exhausted of air the steam entering promptly fills the free spaces surrounding the load.
As steam contacts the cool outer layers of the fabrics a film of steam condenses, leaving a minute quantity of moisture in the fibres of the fabrics.
Air contained in the fabric interstices, being heavier than steam, is displaced by gravity in a downward direction, and the latent heat given off during the process of condensation is absorbed by that layer of the fabrics. fig 2.15
The next film of steam immediately fills the space created when the first film condensed into water, and it does not condense on the outer layer of the fabrics but penetrates into the second layer, condenses and heats it.
This process continues until the whole load is heated through and no further condensation occurs, the temperature within the pack remaining at that of the surrounding steam.
Any questions be sent to drmmkapur@gmail.com
All posts are stored in archives for your access and review
These are thermostatic controlled ovens, with an electric heating element, similar to a domestic electric oven.
- Instruments to be sterilized are heated to 160 degree C (320 degree F) for 1 hour.
- Sterilization is achieved, but it is not suitable for rubber or plastic instruments.
- In hospital has been used for sterilizing powders and petroleum products and sharp delicate instruments
The efficiency of dry heat sterilization depends on the initial moisture of the microbial cells, but all microorganisms are killed at 160 degree C for a hold time of not less than 2 hours.
The main advantages of dry heat sterilization are its ability to treat solids, non-aqueous liquids, grease/ointments and to process closed (airtight) containers.
Lack of corrosion is important in the sterilization of non-stainless metals and surgical instruments with fine cutting edges.
WHAT ARE AUTOCLAVES?
This is the most efficient method of sterilizing instruments, packs and dressings, and is suitable for most materials.
An autoclave is basically a pressure cooker and in fact, there is no reason why a domestic pressure cooker should not be used to sterilize instruments in a small clinic.
The small autoclaves produced for the doctor's surgery offer a choice of temperatures, pressures and sterilizing times:
The highest temperature that can be reached by boiling water at sea level in an open vessel is 100 degree C.
With increased pressure, the water can be raised to much higher temperatures before it boils, e.g., at a pressure of 0.35 kg per cm2 (5 p.s.i.) the temperature reaches 105.5 degree C: at 0.7 kg per cm2 (10 p.s.i.). 115 degree C; and at 1.05 kg per cm2 (15 p.s.i.) the temperature will reach 121 degree C, etc. In a sterilizer chamber (autoclave) which has been well exhausted of air the steam entering promptly fills the free spaces surrounding the load.
As steam contacts the cool outer layers of the fabrics a film of steam condenses, leaving a minute quantity of moisture in the fibres of the fabrics.
Air contained in the fabric interstices, being heavier than steam, is displaced by gravity in a downward direction, and the latent heat given off during the process of condensation is absorbed by that layer of the fabrics. fig 2.15
The next film of steam immediately fills the space created when the first film condensed into water, and it does not condense on the outer layer of the fabrics but penetrates into the second layer, condenses and heats it.
This process continues until the whole load is heated through and no further condensation occurs, the temperature within the pack remaining at that of the surrounding steam.
Any questions be sent to drmmkapur@gmail.com
All posts are stored in archives for your access and review
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