Tuesday, September 05, 2000Scribe: Melissa Chan

Tuesday, September 05, 2000Scribe: Melissa Chan

Pathology 1 pmProof: Anita Sandhu

Dr. Bradley

Environmental Pathology I

Introduction: Dr. Bradley introduced himself and talked about his background, etc. He thinks that environmental pathology is a pretty important subject especially since these 4 hours in path this week is probably the only exposure we will have of it . . . ever. He asked the question “where does disease come from?” Answer: 1. genetics, and 2. environment. The environment takes its toll on us whether we realize it or not. As far as test questions go: 1. will cover things in the handout, 2. first ½ of Chapter 10 in Robbins that goes over environmental pathology (not nutrition), and 3. stuff said and shown in class. Thus, attendance is recommended (for those with strong stomachs) since there is stuff in lecture that is not in the book or handout ‘cuz he wants to reward those people who show up. Scribe note: Dr. Bradley showed a lot of slides. If it had words in it, it is included here in larger font, while anecdotes told in the lecture are simply summarized. Most of the picture slides are of severed, mutilated, and/or electrocuted hands, legs, eyes, etc. etc, etc . . . There are also lots of pictures of all types of tractors modeled in every position with various people or body parts hanging under or dangling off them.

Slide 1:

Air pollution: air pollution is the presence of pollutants in the form of bacteria, gases, fiber, particles of foreign material in the air that is inhaled. Daily, an average person inhales 10,000 to 20,000 liters of air.

Air has all kind so of things in it besides oxygen including dust particles, as we know very well in west Texas. There are also mold spores, fungi, pesticide residues, and these are not necessary beneficial to us.

Slide 2: Indoor Air Pollutants:

PollutantsTypical sources

SO2tobacco, wood and coal stoves

NO, NO2gas ranges, pilot lights

Infectious biologicsbacteria, fungi, virus

Allergenic biologicsdust, mites, animaldander, mold

Formaldehydeglue, wood particleboard, plywood

Radonsoil under building

Asbestosbuilding insulation

Semi-volatile organicspesticides, charcoalburning, etc.

The same kind of pollutant that is in outdoor air can also be found indoors, although usually not quite as severe. (I’ve highlighted the ones he specifically mentioned). Since formaldehyde is used to protect fabrics, you can sometimes smell it in stores. As a shopper, it probably won’t bother you too much since you are not in the store for long, but that is a different picture if you work in the store. Asbestos was found in public buildings, such as schools, as an insulating material before people realized that it is carcinogenic. (Observe that the ceiling above our heads in the classroom had to be repainted due to asbestos removal.) Sometimes it is cheaper simply to tear down and rebuild the building than to strip and repaint the entire thing. We think the air that we breathe is clean and pure, but that is not the case. His goal is to make us look at the environment in a different way than we do now so that when we see patients, we will recognize that they live in a particular environment that we may not live in. Where they live may be very different from where we live, and their environment may actually affect their health.

Slide 3: Tobacco Smoking

Results in 21% of all mortality in US. Single most important cause of premature deaths in US. Greater than 25% of Americans continue to smoke.

If you look in Robbins (page 409), there are two tables shown about tobacco smoking and its influence. About 30% of all cancer of any kind is related to tobacco smoking. More than 90% of all lung cancer is related to tobacco smoking.

Slide 4: Illnesses related to tobacco smoking

MI, stoke, lung cancer, emphysema, chronic bronchitis, laryngeal cancer, esophageal cancer, kidney cancer, pancreatic cancer, bladder cancer . . . (I wasn’t fast enough to scribble down the rest, but you get the general picture.)

Dr. Bradley tells about how his friend (a long time smoker) was recently diagnosed with bladder cancer. Various oral cancers from pipes and smokeless tobacco are also included on this list.

Slide 5: Pneumoconiosis – a general term that is related to dust/particulate matter that is inhaled into the lung. It relates to . . .

1. coal worker’s black lung – developed in people who worked in mines in Kentucky and W. Virginia and inhaled dust into their lungs. It can also occur to masons who work in rock quarries. When they cut stone, the silicate that is in the rock will get into their lungs and cause problems.
2. farmer’s lung – people who work on farms, and consequently handle moldy hay, will develop this.
3. Byssinosis – developed by people working in the cotton industry who breath cotton fiber in the air
4. Berylliosis
5. Asbestos
6. silicosis
7. anthrocosis

Slide 6 & 7: Silicosis picture in a lung.

Can see dark deposits (coal dusts) with nodules. Takes about 12 years working in a coal mine to develop this. If you begin working in a coal mine at age 20, then by age 32, you’ve developed this debilitating coal worker’s lung so you can’t work anymore (and consequently become unemployed). This kind of thing doesn’t happen much anymore because we have strip mining instead of dip mining, which is good for health, but bad for earth, water, etc.

Water pollution is similar to air pollution since whatever can pollute the air can also pollute water.

Slide 8: Silicotic nodule

Looks like an onion. A typical nodule that came out the lung of a worker who worked in a stone quarry.

Slide 9: Mechanical Force Injury

Obviously can injure soft tissue but can sometimes go down through muscle to bone. We will look closely at some of these injuries and see where they come from. These are all in environmentally related situations.

Soft tissue injury

a. Superficial – skin injury

b. Deep – visceral injury

Bone injury

Head injury

Slide 11 & 12: You can injure your back by bending over to pick up heavy stuff incorrectly (such as not lifting the object with your legs but with your back instead). A very common problem among the elderly. Sitting on the tractor too long (for years) and inaccurately will take a toll on the back. Same for truck drivers.

Slide 13 - 15: A guy with his head stuck under a tractor. (Photos in various angles and close-ups.)

His wife watches the clock wondering where this guy is. The point of this: The poor guy is more likely to have a favorable outcome if: 1) medical attention is obtained immediately and 2) if he is taken to a metropolitan hospital (with a level 1 trauma center) instead of a little clinic in a little town. Since his head is stuck under a John Deer on a remote farm, it isn’t likely that he’ll receive superior medical attention anytime soon. : (

Slide 16 - 21: Now kids, just keep your hands to your self . . .

Mutilated hand, recovering stages of mutilated hand, recovered mutilated hand with and without prosthetic hand:

He showed these pics just to prove that some of these injuries can be severe . . . Apparently, someone tried to unclog a corn picker with their hand while the dang thing was still running. Slide 19: “Farm Hand” – This Texas farm hand is from our own HSC emergency room. It could not be reattached. Another corn auger accident. Slide 20: Ditch Witch – A machine used to carve a ditch in the ground for laying down wires. Anyhow, another severed hand only this time, the machine extracted the hand away from his arm. You can see tendons dangling from the severed hand. Slide 21: Chainsaw – Guess what accidents this can cause. His high school friend got his leg caught in one of these.

Slide 22: Causes of these accidents – fatigue, long work hours, lack of vacation, unsafe habits, lack of safety training, lack of safety regulation.

These people had no previous health problems, but they were caught in these jams because of the work that they do and where they live. Also fatigue and long work hours of these rural workers cause them to make mistakes. Football analogy: get more fouls and penalties in 4th quarter when everyone is tired. People need a break from what they are doing and see some different scenery, hence vacation is necessary. Many other people simply have unsafe habits or lack of training.

Slide 23 & 24: Safe tractor vs. Unsafe tractor:

The unsafe tractor doesn’t have any protective covering so you could get loose clothing caught in it. It also has an open-air cabin, which leaves the driver exposed to all weather conditions. However, there are homemade roll bars that may prevent rollover accidents that crush the driver. The safer tractor has a cabin with A/C, stereo, and tractor phone.

Slide 25 - 27: Unsafe habit: 2 people on 1 tractor (Grandpa and Granddaughter), Granddaughter is an inexperienced tractor driver

The Grandpa may not be able to jump clear when the tractor begins to flip over, while the Granddaughter jumps for her life. Result: Grandpa lost his leg. This is an environmental hazard because before the Granddaughter drove the tractor with him, Grandpa was in great health.

Slide 28: Prevention

Get a cab or rollover bars

Rearview mirror

Proper lighting

Seat belt – just as important in a tractor as in a car when it is about to turn over.

Slow-moving vehicle sign

Slide 29: Traumas of the head

Dr. Bradley reminds us here that we are not going to find all of this stuff in the notes. He is trying to supplement the notes and the book. Okay.

Slide 30-33: Tractor with anhydrous ammonium (fertilizer) tank

Anhydrous ammonium causes serious burns. This is why a tractor that tows a huge tank of this nasty stuff is supposed to carry a little red tank of water on top just for emergencies. Well, sometimes people forget to fill the water tanks so that when there is an accidental splash of anhydrous ammonium, there is no water to wash yourself with. Get this stuff in your eyes, and it can cause blindness (as evidenced by the pictures he showed). Anhydrous ammonium freezes and desiccates tissue, causes alkali skin burns, damages respiratory tract, penetrates cornea, and causes blindness. For these types of alkali skin burns, must get water on it ASAP or serious burns can occur. Time is critical!

Slide 34 – 39: Don’t turn around to look if the tractor goes “crunch”.

A woman is using a tractor to cut grass. A coiled up barbed wire hides stealthily in tall grass. Tractor goes over the barbed wire. Barbed wire makes tractor go “crunch”. Woman turns around to look. Flying barbed-wire-shrapnel lands in right eye. No more right eye. Point: wear protective eye gear (glasses, sun-glasses, goggles) or get a tractor with a cab.

Slide 40: Skin Injuries due to mechanical force (in the handout)

Abrasions

Lacerations

Incision

Contusion

Gun-shot wound

Slide 41: Gun shot wound picture – (similar to page 433 of Robbins) Simple but deadly wound. Even though there is no significant external damage, the internal damage is severe.

Slide 42: Factors determining Clinical Significance of Cutaneus Burns

1. % of the total body surface involved – in the notes
2. depth of the burn (through partial or full-thickness of the skin)
3. internal injuries from hot gases and fumes in inhalation
4. promptness & efficacy of post-injury therapy

He lets us know that there is a patient in the burn center right now who was involved in an explosion down near El Paso. They were camping when a gas-line erupted.

Slide 43: Figures of first, second, and third degree burns

The first degree is not nearly as bad. It consists of superficial burning of the skin. Example: sunburn. Second-degree burns are a little more serious. It actually burns thru the epidermis into the dermal layer. The third degree burn will get down into the muscle tissue. Know about these. (It’s in the handout in detail)

Slide 44 – 47: Electrical burn

These pictures are from a teenager that lived in Lubbock three years ago. He tried to impress his girlfriend by going to the electrical box and turning off the electricity of his apartment complex (in the rain). Bad idea. Consequently, Dr. Bradley got multiple pictures and close-ups of his severed hand and foot that show severe burns. Electrical burns are very serious. It can also happen from lightening. A month ago in Kentucky, a man living in his trailer on his parents’ farm near his parents’ house got struck by lightening when he was on his way to his parents’ house to avoid this severe thunderstorm. He was carrying his 3-month-old baby. He died instantaneously because lightning goes through the body to the ground, but the baby was hardly injured at all with only a slight abrasion on the head.

Slide 48: Hypothermia – can of course occur if the entire body gets cold. If the person’s core body temperature drops, he can get general hypothermia. However, hypothermia can be restricted to hand and feet, etc.

Whole body exposure

Skin blanches then reddens – this whitening of the skin from hypothermia usually occurs from the blood shifting internally. The body does this to try to keep the core body temperature at a norm, sacrificing the extremities. Now if the person survives this hypothermia and gets back to normal state, then the blood will begin to equilibrate. At this point, the skin will redden where the hypothermia has occurred. If severe enough, death results from brain/heart dysfunction.

Exposure of parts (frostbites) - often occurs at ears/toes/hands

1. ischemia
2. hypoxic changes
3. infarction necrosis

Slide 49: A frostbitten hand – he only showed it. No comment made.

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