Patients With Blood-Borne Infections
A single policy should be devised to cover clinical entities which are transmitted via blood and body fluids such as HIV, HBV, HCV, syphilis, and malaria The policy should assess the risks to the staff and patients and should apply to all departments dealing with blood and blood products ie. Renal dialysis, operating theatres, labour ward, blood transfusion centre, and transplant units. There must be clear policies on screening patients, screening staff before they start work on the unit, disposal of sharps and waste, protective clothing, inoculation accidents and policy, sterilization and disinfection. Other points to consider include isolation facilities, procedures for dealing with spillage of blood and body fluids, intravenous procedures, and risk to staff. Good practices and adequate staff training should minimize the risk to staff, although extra care is needed with these patients.
General Infection Control Measures
Protective clothing - universal precautions means that particular high-risk procedures are always dealt with using protective clothing such as gloves, aprons etc. Countries with a low incidence of blood-borne diseases sometimes practice a tow-tier system (protective clothing is only used for known high-risk patients such as HIV or HBV-positive patients). A single-tier system (where universal precautions are applied to all patients) should be practiced when the incidence is high. Gloves should be made of latex and fit well. Plastic aprons should be worn to protect staff from body fluids, as in the case with gloves, disposable aprons are preferable to reusable. Goggles or visor should be worn to avoid conjunctival splash contamination, although spectacles are acceptable. Masks are used to avoid blood or body fluids splashing into the moth and nostrils.
Isolation facilities - single cubicles should be provided only for patients who need high-dependency nursing, such as those with a poor standard of hygiene.
Spillage of blood and body fluids - spillages should be dealt with as quickly as possible with latex gloves. The spillage should be covered with hypochlorite granules (presept) or paper towels soaked with hypochlorite solution (1000 to 10000 ppm). At least 2 minutes of contact time should be allowed before the spillage is cleared and disposed of as clinical waste The surface is then washed with warm water and detergent
Sterilization and disinfection - hypochlorites are recommended for surfaces and 2% glutaraldehyde for heat-sensitive equipment and metals.
Intravenous procedures - these must be performed with great care by an experienced practitioner. Gloves and plastic aprons should be worn; eye protection is optional. A closed system (Vacutainer) is recommended but if a hypodermic needle and syringe is used, the whole unit must be discarded in a sharps container. Do not resheath needles. Devices which reduces the risk of needle stick injuries such as vacutainers, retractable needles should be considered for general use although they are expensive.
Collection and transportation of blood from patients - an absolute minimum of tests should be performed on high risk patients. If possible, specimens should be collected in a closed system (vacutainer), labelled clearly, and put in a leak-proof bag with request form and warning label. Venepuncture should only be performed by an experienced phlebotomist. Double gloves may be worn and a disposable paper towel should be placed beneath the patients arm to reduce contamination in the event of accidental spillage Any gauze or soiled paper towels should be discarded in the clinical waste bag. The transfer of blood to the appropriate container should be done slowly and carefully and without creating an aerosol. Needles should not be resheathed but discarded in the sharps container. However, if resheathing is absolutely necessary, use a mushroom device, which holds the cap so the needle can be introduced safely. Alternatively, lay the cap on the table with the closed end against anything that offer resistance and insert the needle carefully - never hold the cap while resheathing.
Staff protection and immunization - all staff working with category A patients (HBV, HIV) must be immunized against HBV. staff should have adequate training in the care of patients who are HIV or HBV positive. Clear policies of safety, covering inoculation accidents must be available. All inoculation accidents must be recorded and documented. Frequent lectures are essential to allay fear and promote good morale
Needle-stick injuries - if a non-immunized member of
staff sustains a needle-stick injury from a e Ag positive HBV
carrier, he should be offered HBIG and a course of vaccine. If
the source is not eAg positive, then a course of vaccine alone
would be sufficient. If the source is known to be HIV-positive,
then AZT may be administered within 24 hours of exposure and
counseling should be offered.
Operating theatres and labour wards
There has been much discussion about the protection of staff operating on HIV and HBV positive patients. Recent figures from the US show that the overall risk of acquiring a blood-borne disease is 0.3% in surgical operation. The following guidelines are advised during the operation or procedure;-
After the operation, all disposable, incinerable waste should be removed in clearly labelled colour-coded bags. Surfaces should be washed with warm water and detergent. Walls should be washed up to ahnd height with water and detergent. Blood and body fluid spillages should be spotted with hypochlorite. Heat-stable equipment should be sent for sterilization and labelled "high risk". Respiratory equipment should be disinfected by heat or glutaraldehyde. Larger machines should be wiped with warm water and detergent to remove organic contamination. This is sufficient unless heavy soiling has occurred. In that instance, they should be wiped with hypochlorite.
Renal dialysis unit
The same basic principles apply to the renal dialysis unit as for the theatre and delivery room. Staff should be immunized against hepatitis B before starting work in the unit. All patients should be screened and immunized against hepatitis B. Machines should be reserved for the exclusive use of HBsAg carriers. Disposable tubing and heat-labile equipment are recommended for dialysis. The outer surfaces of the dialysis machine should be cleaned with warm water and detergent. The inside of the machine should be disinfected with 1% hypochlorite and rinsed thoroughly before further use. Disposable filters should be used to prevent contamination with blood. Disposable administration lines, dialyser, and needles should be used. Re-usable equipment must be able to withstand autoclaving.
Category A contact isolation is advisable for patients with HBV and HIV infection after surgery. Although not strictly necessary, it would be prudent to put the patient into a single room after the operation so that the risk to other patients in the ward is minimized. Whilst looking the patient, masks would not be necessary except for procedures such as endotracheal aspiration or changing the drainage bottle. Plastic gloves should be worn at all times and any cuts and bruises covered adequately. Any blood spilled onto the floor should be decontaminated with chlorox immediately. Extra care must be observed if blood is to be taken from this patient using venepuncture so that needle stick injuries are avoided. The same vigilance applies to the insertion of IV lines. Any waste material taken from the patient, such as wound dressings should be discarded into well-marked disposal bags and incinerated. It would not be necessary to have separate eating utensils for the patient provided that the washing machine goes up to 80oC. However disposable utensils would further minimize the risks.
HIV Transmission and Assisted Conception
Limitation of risks of transmission of any infection from donor to recipient is a major concern in overcoming infertility using donor gamates. Very specific guidelines have been issued by the RCOG.
A careful history should be taken from men wishing to be sperm donors. As with blood donors, careful attention should be paid to the sexual history, recent travel to, or sexual contact with persons living in areas of the world where HIV is endemic, a history of blood transfusions, or intravenous drug use. After suitable counseling, all prospective donors are required to have HIV and HBV tests, in addition to screens for other STDs. In addition, in order to prevent transmission of infection, it is mandatory that sperm be quarantined by cryopreservation for a period before use, normally 3 to 6 months, with the sperm being released for use following a further negative HIV and HBV test on the donor. The use of fresh donated sperm for insemination is now prohibited in the UK.
Ovum donation presents a particular problem as the equivalent technology for cryopreserving unfertilized oocytes has yet to be developed successfully as pregnancy success rates using frozen embryos are lower than using fresh embryos. However, most ovum donors are in stable heterosexual relationships and embark on ovum donation for altruistic reasons. Therefore they are a low risk population for HIV and fresh oocyte donation is allowed in the UK.
Intrauterine insemination where the male partner is known to be HIV positive
Many HIV-discordant couples wish to have children notwithstanding the risks associated with unprotected intercourse, estimated to be 1:100 episodes of intercourse. Although some reduction in risk may be made by decreasing the frequency of unprotected intercourse by monitoring ovulation and timing intercourse, there has been recent interest in the use of artificial insemination with semen processed to remove infectious virus. To date, no seroconversions had been seen in the 28 couples who participated in the study involving Percoll separation and "swim up". Further investigation is needed before this type of technique is declared safe.
In vitro fertilization
There is no statutory requirement for patients participating in in-vitro fertilization procedures to be screened routinely for HIV. However, some units will screen high-risk couples, while others make it a condition of acceptance, either for protection of the laboratory staff, or in the interests of the "welfare of the child", will refuse treatment for HIV-affected couples.