Infect ion Control in the Department of Nuclear Medic ine

Audrey Adams and Angela Egan

Concern about the spread of infections in the hospi- tal sett ing has prompted regulatory agencies to mandate infection control standards. Each hospital depar tment is required to have wr i t t en policies and procedures which describe measures to prevent and control the spread of nosocomial infections (hospital acquired infections), along wi th qual i ty assurance programs to assure that procedures are fo l lowed. The Department of Nuclear Medicine, as o ther departments, should have procedures which address special precautions for the prevention of nosocomial

infections. This article will focus on a new approach to prevent nosocomial infections, guidelines for han- dling patients and contaminated equipment, and the importance of quality assurance activities to monitor compliance to established standards. An opening discussion on the routes of transmission, and factors necessary for transmission of infection, will serve as a review to assist with understanding the concept for handling the hospitalized pat ient in a Nuclear Medicine setting. �9 1988 by Grune & S t r a t t o n , Inc.

T R ANS MISSION of infection occurs by four main routes: contact, airborne, and vehicle

and vector borne. Contact transmission has been described as the most important and most fre- quent means of transmission of nosocomial infec- tions.~ Direct contact, indirect contact, and drop- let contact are the three subgroups of contact transmission.

Direct contact involves physical transfer from the source directly to the recipient without an intermediate object (one person touches anoth- er). An example would be the fecal-oral spread of salmonella via contaminated hands. Indirect con- tact refers to transfer of the organisms from the source via a contaminated intermediate object, which is usually inanimate, such as instruments, needles and dressings. Droplet contact occurs when the infectious agents are transmitted from the source via droplets as a result of coughing, sneezing or talking. These droplets may come in contact with the conjunctiva, nose, or mouth of susceptible individuals. Droplets travel no farther than 3 ft and never become indepen- dently airborne. Most infection control proce- dures used in a hospital setting are focused on the prevention of contact transmission, direct and indirect.

Airborne transmission is the dissemination of the infectious agent via droplets (usually by coughing, or resuspended dust). The droplet evaporates, leaving tiny droplet nuclei suspended in the air. These droplet nuclei contain the infec- tious agent which must be breathed in by a susceptible host. Tuberculosis and chicken pox are spread by the airborne route.

Vehicle transmission refers to contaminated items such as food, water, or blood which may serve as the source of infection. Multiple cases of

disease may be associated with this source of infection. Transfusion-related hepatitis non-A, non-B is an example of vehicle transmission in a hospital setting.

Vector-borne diseases, such as mosquito- transmitted malaria, are of greater concern in tropical countries, and are not significant in the hospitals in the United States.

THE CHAIN OF INFECTION

For transmission of infection to occur six links are needed to complete the chain of infection. A causative agent is the first link (an organism). A susceptible host is the second link (nuclear medi- cine technician). A portal of exit (mucous mem- brane-lined opening--nose, throat, rectum), and a mode of transmission (airborne, contact) are the third and fourth links. A portal of entry (mucous membrane or cutaneous openings) and reservoir for the organism to grow and proliferate (lung, bladder, colon, blood, etc) are the last two links (Fig 1).

PREVENTION OF NOSOCOMIAL INFECTIONS

The prevention of nosocomial infections and cross-contamination have traditionally been based on routine infection control policies and procedures. The handwashing procedure has

From the Department of Nursing and the Department of Nuclear Medicine, Montefiore Medical Center, Bronx, NY.

Address reprint requests to Audrey Adams, RN, CIC, Administrative Nursing Supervisor, Infection Control, Department of Nursing, Montefiore Medical Center, 111 E 210th St, Bronx, NY 10467.

�9 1988 by Grune & Stratton, Inc. 0001-2998/88/1804-0008505.00/0

Seminars in Nuclear Medicine, Vol XVlll, No 4 (October), 1988: pp 345-349 345

346 ADAMS AND EGAN

Fig 1, Chain of infection.

been recognized as the single most important means of preventing the spread of infection. Isolation precaution procedures based on the Centers for Disease Control's (CDC) recommen- dations, "Guidelines for Isolation Precautions in Hospitals, ''2 have been implemented in most hospitals across the nation to protect patients and staff from infectious agents of patients suspected or known to be infected. These isolation precau- tion procedures may require the use of private rooms to prevent the spread of the infectious agent to others. Protective barriers such as gowns, gloves, or masks may be worn by hospital personnel. When a patient on isolation precau- tions is required to leave the unit for a special procedure such as a gallium scan, the Nuclear Medicine Department should be notified in advance so that protective measures can be ini- tiated.

The use of these traditional isolation precau- tions as means of preventing nosocomial infec- tions have recently come under scrutiny. The effectiveness of these procedures are limited to

those suspected or known to be infectious. 3 Hos- pitalized asymptomatic carriers of infectious agents may go unrecognized on no isolation precautions. This is especially true with acquired immune deficiency syndrome (AIDS) and hepa- titis B carriers. In the May 22, 1987 Morbidity and Mortality Weekly Report, CDC reported three cases of health care workers (HCW) who contacted the AIDS virus through possible cuta- neous and mucous membrane exposure to the blood of unidentified infected patients. 4 As a result, the American Hospital Association and CDC issued specific guidelines and recommen- dations for Universal Precautions. 5'6 The US Occupational Safety and Health Administration (OSHA) has also issued similar regulations. 7 Universal Precautions is an approach to treat blood and body fluids of all patients as infectious. Some hospitals had implemented this system before the recommendations. 8 Other hospitals are revising CDC's traditional diagnosis-related isolation precautions to be consistent with Uni- versal Precautions.

Table 1. Universal Precautions for in v ivo Procedures

Handwashing

Protective Barriers

Gown (or Waterproof Gloves Apron Mask

Collimator Protectors *

Before direct care, or in- Touching blood and During procedures in During procedures re- All procedures in which

vasive procedures body fluids, mucous which blood and body quiring the use of a contamination of the such as venipunctures membranes or non-in- fluids might come in nebulizer such as a collimator with blood

to obtain blood sam- tact skin. Handling in- contact with uniforms lung ventilation scan or body fluids is likely piss or administer ra- struments or surfaces such as: only if aerosolization such as patients with

diopharmaceuticals soiled with blood or 1. GI bleeding scan and or spray to the face wound dressings,

Between patients body fluids patient is actively with secretions is an- non-intact skin, skin After removing gloves Performing venipunc- bleeding ticipated or patient is lesions, urine, or fecal

Immediately if contami- tures 2. Voiding cystography on airborne isolation incontinence, vomit=

nated with blood or Gloves should be if child is uncoopera- ing, productive cough, body fluids changed after contact tive and urine is likely and GI bleeding

with each patient to be splashed Collimator protectors should be discarded

after each patient

For in vivo procedures such as bone, lung, GI, and gallium scans. Abbreviation: GI, gastrointestinal.

*Any type of disposable plastic sheet can be used, such as saran wrap or plastic sheets specifically designed to keep the face of the scintillation camera collimator from becoming contaminated. 9

INFECTION CONTROL IN NUCLEAR MEDICINE

Table 2. Universal Barrier Precautions for in vitro

Procedures

Situations Requiring Protective Barriers Protective Barriers

Handwashing Before all injections, blood with-

drawals and procedures requiring the handling of material which is

to be injected into the patient Immediately if contaminated with

blood or body fluids After completion of each lab proce-

dure Gloves All personnel processing blood and

Gowns (or plastic

apron)

Masks/eye covering

Mechanical pipetting devices

Impervious containers

body fluid samples

Performing venipuncture or manipu-

lation of stopcocks to obtain blood samples or administer la-

beled RBC Handling instruments soiled with

blood or body fluids Removing caps from specimen cups

and vacuum tubes

All personnel processing blood and body fluids which are likely to

generate splashes During procedures that require mea-

suring, blending, and mixing of body fluids that might cause

droplets or splashing, such as gastrointestinal absorption and elimination studies, l~ or proce-

dures that are likely to cause aer-

osolization of body fluids such as centrifugation of blood samples

Procedures such as red cell survival

studies that require transferring of blood samples to counting

tubes 1~

All blood and body fluids requiring refrigeration storage, such as

blood samples for renin studies, should be placed in impervious

containers or bags to prevent spillage and contamination of the

refrigerator

For in vitro procedures such as RBC mass, plasma volume,

RBC survival, Schilling test, total blood volume, and other lab

procedures.

A NEW APPROACH TO PREVENT NOSOCOMIAL INFECTIONS

Universal Precautions, as outlined by CDC, is a new approach to prevent nosocomial infections. It will protect the HCW from exposure to known and unknown infectious agents. It also encour- ages routine safe practices to prevent cross- infection. The following are major components of

347

Universal Precautions: 1. The use of protective barriers:

a. Gloves should be worn for contact with mucous membranes, non-intact skin, blood and any body fluid. They should be changed after each patient contact, and hands washed.

b. Masks and protective eyewear should be worn for procedures which are likely to generate droplets of blood or body fluid.

c. Gowns or plastic aprons should be worn during procedures which are likely to generate splashes of blood or body fluid.

2. Hands and skin surfaces should be washed immediately and thoroughly if contami- nated.

3. Sharp Objects. Care should be taken to avoid injuries with needles, scalpels and other sharp instruments or devices. Needles

Table 3. Procedures for Decontamination of Equipment

and Environmental Surfaces

Procedure tables and scintillation cameras

Lab work surfaces

Floors, counter tops, and other surfaces

Linen should be changed after each

patient. Protective barriers (see Table 1 ), should be used on diffi-

cult-to-decontaminate equipment parts such as scintillation camera

collimators. Procedure tables and

other equipment that become soiled with blood and body fluids

should be decontaminated imme- diately with a chemical germacide

such as 5.25% solution hypo- chlorite solution (household

bleach) in a 1 : 10 dilution All lab work surfaces should be de-

contaminated with a chemical

germicide such as 5.25% sodium hypochlorite following spills of

blood and body fluids and at the completion of the working day

Routine cleaning schedules should

be established. Special proce-

dures for decontamination are not indicated unless surfaces are con-

taminated with blood and body fluids. All work surfaces and

floors should be cleaned daily with soap and water. Disinfectant

detergent formulations registered by the Environmental Protection

Agency can be used

Gloves should be worn for all cleaning and decontaminating

procedures.

348 ADAMS AND EGAN

and all sharp objects should be discarded in puncture-resistant containers.

4. Ventilation devices should be available in areas where the need for resuscitation is predictable.

5. Blood and body spills should be cleaned with a chemical germicide such as a 1:10 dilution of household bleach.

Employees need to be familiar with and adhere to the recommendations suggested by the CDC. Tables 1 through 3 will provide a guide for implementation of universal precautions in a nuclear medicine setting.

QUALITY ASSURANCE ACTIVITIES

The goal in establishing procedures for univer- sal precautions is to assure quality care to all patients and provide a safe environment for employees. Once these procedures have been established, the next step is to provide infection control continuing education programs for all nuclear medicine employees and conduct quality assurance activities that will monitor compliance to established procedures.

Educational programs should include the rec- ommendations made by the Department of Labor /DHHS made in an advisory notice issued to health care employees throughout the United States, entitled: "Protection Against Occupa- tional Exposure to Hepatitis Virus (HBV) and Human Immunodeficiency Virus (HIV)." This notice advised health care employees to establish training programs for all employers who perform procedures or job-related tasks in the following categoriesT:

Category I

Tasks that involve exposure to blood, body fluids or tissues, or the potential for skin or mucous membrane contact from spills or splashes of these substances.

Category H

Tasks that involve no exposure to blood, body fluids, or tissues, but exposure may be required as a condition of employment.

Category III

Tasks that involve no exposure to blood, body fluids, or tissues, but work routine may involve

Table 4. Criteria for an Infection Control Quality Assurance Screen in the Department of Nuclear Medicine

1. Hands are washed between patients and after Yes/no

removing gloves 2. Appropriate barriers are used for venipuncture Yes/no

to administer radiopharmaceuticals and draw blood samples

3. Protective barriers are placed on difficult-to- Yes/no

decontaminate equipment

4. Procedure table linen is changed after each Yes/no patient

5. Correct procedure is followed for decontami- Yes/no nation of blood and body fluid spills

Problems identified:

Action plan:

Follow-up:

handling of utensils, use of public or shared bathroom facilities or telephones, and personal contacts such as handshaking.

Infection control inservice education programs for all health care workers are important to review standard procedures. In the Department of Nuclear Medicine, educational programs should be repeated at least annually to provide an ongoing review of standard procedures and an opportunity to update policies as new informa- tion becomes available. Upon completion of initial inservice training, quality assurance activ- ities to monitor compliance should then be incor- porated in the quality assurance program of the department.

A number of quality assurance activities to monitor compliance have been described in the literature, such as quality assurance screens based on predetermined criteria 1] (Table 4).

Quality assurance screens can be lists of events that should not occur, H J2 eg, transfer of a patient with an airborne disease to the Department of Nuclear Medicine without appropriate barrier (mask); not using appropriate barriers (gloves) when handling blood and body fluids of any patient; neglecting to decontaminate work sur- faces contaminated with blood and body fluids, and/or neglecting to decontaminate lab work surfaces at the end of the working day.

INFECTION CONTROL IN NUCLEAR MEDICINE 349

I f app l ied cor rec t ly , and the pr inc ip les o f d a t a

co l lec t ion a r e observed , qua l i t y a s su rance screens

can be used by any h e a l t h ca re profess iona l

f a m i l i a r wi th es t ab l i shed procedures . ~3 T h e d a t a

co l l ec ted will p rov ide d i r ec t ion for f u t u r e ac t ion

p lans such as counse l l ing , educa t ion , and i f nec-

essary, a p p r o p r i a t e d i sc ip l ina ry ac t ion tha t will

a s su re a p p r o p r i a t e m a n a g e m e n t of pa t i en t s and

a sa fe r e n v i r o n m e n t for emp loyees in t he D e p a r t -

m e n t of N u c l e a r M e d i c i n e .

REFERENCES

1. Castle M: Hospital Infection Control. New York, Wiley, 1980

2. Garner JS, Simmons BP: Guideline for isolation pre- cautions in hospitals. Infect Control 4:245-325, 1983

3. Lynch P, Jackson M: Rethinking the role of isolation practices in the prevention of nosocomial infections. Ann Intern Med 107:243-246, 1987

4. Centers for Disease Control. Update: Human Immuno- deficiency Virus Infections in Healthcare Workers Exposed to Blood of Infected Patients. MMWR 36:285-288, 1987

5. American Hospital Association. Statement of the Advisory Committee on Infections Within Hospitals on Pro- tection of Health Care Workers. Chicago, American Hospi- tal Association, June 18, 1987

6. Centers for Disease Control. Recommendations for prevention of HIV transmission in health care settings. MMWR 36:2S-185, 1987 (suppl 2S)

7. Federal Register. Joint Advisory Notice, Department

of Labor/Department of Health and Human Services. HBV/ HIV. Vol 52, no. 210, October 30, 1987, pp 41820-41821

8. McPherson D, Jackson M: Isolation Precautions. J Healthcare Material Manage 5:28-32, 1987

9. Nuclear Supplies and Accessories--The Nuclear Med- icine Source, "Collimator Protectors," Catalog #58. New York, International Medical Products, 1986, p 25

10. Sodee DB, Early PJ: Mosby's Manual of Nuclear Medicine Procedures (ed 3). St Louis, Mosby, 1981, pp 256-301

11. Bruskewitz MA: Observation as an evaluation tool, in Schroeder R, Maibusch RM (eds): Nursing Quality Assur- ance: A Unit Based Approach. Rockville MD, Aspen, 1984, pp 157-169

12. Motet E: Monitoring is only the beginning. J Nurs Quality Assur 1:23-27, 1987

13. Capdow P: Questions on quality. Nurs Times 82:42- 43, 1986