HAZARDS OF ANAESTHESIA

G.K.KUMAR

DEFENITON

DANGER/RISK ANESTHESIOLOGISTS PATIENTS

HAZARDS FOR ANASTHESIOLOGISTS Fire & explosions Electrical accidents Pollutions by anesthetic agents Radiations Infections Incompatibilities / allergies Stress Chemical dependence

OR

HAZARDS FOR ANASTHESIOLOGISTS PHYSICAL -ELECTRICAL -ENVIRONMENTAL -INFECTIVE -ALLERGY PSYCOLOGICAL -STRESS -DEPENDENCY

Electrical accidents

Unsafe electrical configurations Types-macro shock -micro shock -loss of power supply to

gadgets Safe practices

Electrical accidents Macro shock-Large voltage

current-Causes

tissue damages burns explosions

1ma perception

5ma harmless

10-20maMuscular contraction

50-100ma Pain, fainting

100-2500ma VF

>6000ma Resp.arrest

Micro shock-Direct application of very small voltages to the heart thro’ electrodes

Allowable leakage thro’ electrodes-10µA

>50µA-VF occurs

Electrical accidents

Electrical accidents - Safe

practices

1. Proper grounded equipments(3pin)2. Don’t connect the pt to the OR grounding

sources3. Electro cautery: large grounding pads, to be

kept well away from electrodes & PM4. Use bipolar5. Reset the pace maker to regular

mode(asynchronised)6. Keep ready pharmacological pacing-

Isoprenaline7. Good maintenance of equipments

Pollution by anesthetic agents

Risks Recommendations Remedies

Pollution by anesthetic agents

Risks- Real? Or Mystiques? -abortions -congenital abnormalities -malignancies (liver) -behavioral problems(N2O)

Pollution by anesthetic agents

Recommendations Upper limits N2O 25ppm

Halogenated agents

2ppm

Halogenated agents with N2O

0.5ppm

Pollution by anesthetic agents

Remedies Scavenging systems Closed circuits Anti spill devices Avoid agents

Radiation hazards

Risks Recommendations Remedies

Radiation hazards

Risks Ionizing radiation-X’ray, radioactive

isotopes Formation of free radicals, ionizing

molecules Damage/destruction of cells,

Ch anomalies, malignancies.

Radiation hazards

Risks Non-Ionizing radiation –laser

Disruption of electrons from one orbit to others, but with in cells

Tissue damage Laser plums formation (contain viable

bacteria,HPV DNA,HIVproviral DNA)

Radiation hazards

Recommendations Max. allowable exposure/yr<5Rem during pregnancy-

500mRem 0ne X’ray-25 mRem Natural exposure cosmic rays-

40mRem

Radiation hazards

Remedies for ionizing radiation Scattered rays inv. Proportional to

(distance)2 from the source Best way of protection-physical

separation (6 ft = 9 in concrete = 2.5 mm lead) Protective lead aprons (o.25-o.5mm)

Radiation hazards

Remedies for non-ionizing radiation Radiation intensity not decreased to

distance in an average OR. Proper gaggles Laser plum to be removed by

effective scavenging systems removes particles ≥o.1µm (filters ≥0.5µm).

Infections

Physical spread-HSV,CMV Blood borne-HIV,HBV,HCV Air borne-Mtb

Infections Blood borne diseases thro’ Needle stick

injuries- HIV:0.3%, HBV:3%, HCV30% 32% had at least 1 NSI in the preceding 12M.

(only half of them took treatment). More risk with hollow-core & large bore NSI more in non dominated hands NSI more during disposal of contaminated

needles. Anesthesiologists have risk for occupational

infection during 30years of exposure-0.045-4.5%

Infections-HIV Health care workers contribute 5%

of total cases 4% of emergency department pts

are unidentified cases. Pts considered infective if both

screening (ELISHA) & confirmatory (western blot, indirect fluorescent ab) tests are positive.

Infections-HIV

54 reported cases of occupationally acquired HIV(1998).

88% of them had H/O NSI ? Quantity of inoculums- ( a case

report :100-200µml of blood thro”i.v. produced HIV).

Risk for the pts- 6 cases reported.

Infections-HBV Non immunized health care workers

higher risks 17.8% 0f seropositive among

anesthesiologist 30% became positive after 11 years of

exposure Disinfectants & gloves are not

completely protective- viruses viable for >14 days in needles, gloves, &surfaces.

Infections-HCV

No immunization available No specific treatment available Advice: serologic monitoring for

HCV & LFT 3-6 monthly.

Infections

Management of occupational infections.SAFE PRACTICE1. Protective equipments2. Washing methods3. Disposal methods

Infections -CDC recommendations Universal precautions-1980

-considering as all pts, blood & body fluids are infective.

Isolation precautions-1996

-2 tier recommendations1. Standard precautions -to be followed

for handling all pts as UP.2. Transmission based precautions -for

handling pts known to be / suspected of being risks.

Infections -CDC recommendations

Transmission based precautions Based on specific the properties of specific

pathogens Airborne precautions [measles,varicella,Tb] -to

prevent from small particles<5µm by specific filters air handling devices.-HEPA, Negative pr environment

Droplet precautions [HI-type b, mycoplasma, streptococcal pharyngitis, rubella]-to prevent from large particles>5µm, keep distance>1m

Contact precautions [HAV, HSV, viral conjunctivitis]

Incompatibilities / Allergies

Latex allergy Type iv/ type I Risk groups :

1. Atopics,2. Spina bifida,3. Urogenital abnormalities ,4. HCW, 5. Rubber factory workers.

Latex allergy Managements

1. Identification of risk groups2. Use latex free objects-latex free

environment 3. Tests:RAST[radio-allergo-sorbent test] SPT Sr.histamine Urinary histamine Sr.IgE Sr.compliments Sr.tryptase

Tests for anaphylaxis

Screening tests

Latex allergyManagements-drug regimens Preoperative protocol:

1. Dipenhydramine -1mg/kg,po/iv,q 6hr at 13,7,1hr before surgery

2. Prednisolone -1mg/kg,po/iv,q 6hr at 13,7,1hr before surgery or hydro cortisone 4g/kg

3. Ranitidine - 2mg/kg po, 1mg/kg iv,q 12hr at 13,1hr before surgery

Postop protocol -drugs to be repeated for 12hrs

Stress Inevitable, universal phenomenon

to which no one is immune Job related stress are unavoidable

but may be controlled 2 types-Unavoidable & Avoidable Unavoidable-professional stress Avoidable-sleep related

Stress

Unavoidable Stress Professional Stress Co-worker relationships Work load Litigations Peer review Professional dissatisfaction Administrative responsibilities

Stress

Avoidable Stress Sleep related-altered sleep

pattern, sleep deprivation Coincide with natural sleep

peaks[2-7a.m] Identification of sleep disturbances Regulations of working hours

Chemical dependenceSelf administration of drugs & suicide rates are

high among anesthesiologist. Addiction :compulsive continued use of drugs

in spite of adverse, a chronic, relapsing condition resulting from long term effects of drugs on brain, due to molecular, structural, cellular, & functional changes.

Dependence: physical / psychological inability to control drug use

Abuse :use of drugs in detrimental way but not to the point of addiction. a pre addiction level, can easily quit. a voluntary act.

Chemical dependence

Causes Stress Availabilities Curiosity for experimentation Drug potency Others-genetic predisposition

Chemical dependence

Management Identification Intervention Referral Rehabilitation