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Friday, October 21, 2016

Are Multiple Anesthetic Procedures Safe?

Any time anesthesia is performed on a patient there are certain effects on the body.  Brain activity changes, heart and respiratory rates slow, body temperature drops, blood pressure decreases, heart contraction can change, and many other physiological alterations.  All of this sounds scary, and to some degree it is.  Anesthetizing a patient to a degree where we can perform surgery without them knowing and reacting actually can bring them closer to death than just about anything else we do.  No matter what precautions we take, there is no way to make anesthesia 100% risk-free.

But even with all of that being true, it doesn't mean that we can't have a very safe anesthetic procedure and even do multiple ones in a year.  In fact, that's a common question I will get and the reason for today's post.  We may do a dental cleaning then a few months later notice a lump that we want to remove.  Some clients are worried that performing anesthesia again in the same year will be a big risk and cause complications.  I can assure everyone that this is not the case when done properly.

There are many ways to anesthetize a patient, and the exact drugs, dosages, and procedures will vary from one vet to another.  The anesthetic protocols we use at my clinic aren't "magic" and in fact they were designed in consultation with board-certified anesthesia specialists.  Anyone can use these drugs and procedures.  But the vet down the road from me may give different pre-medications, may induce the pet differently, and may maintain them on a different type of inhaled gas.  Or, they may use the same gas but the rest are different.  There are numerous combinations of protocols available in anesthesia text books and at conferences.  In vet school we are taught several of these techniques so that we learn a variety of methods.  The main take-away on this point is just because one vet performs anesthesia a certain way doesn't mean that every vet will do the same thing.  If you have any concerns ask your vet specific questions about which drugs are used and why.  To give an example, even though this will mean little to most pet owners, we typcially pre-medicate with acepromazine and butorphanol, both at low doses, induce with propofol, and maintain with sevoflurane.  The drugs and dosages may change depending on the pet's health status or the type of surgery being performed. 

Regardless of the protocols used, there is one main thing to remember.  The drugs used have limited duration of effects on the body.  Sevoflurane gas changes it's concentration in the blood stream within a few minutes.  Propofol starts to wear off within a few minutes.  Other drugs may take longer, but they are still completely eliminated from the body within 12-24 hours.  This means that by the day after the surgery the medications used are out of the system and the body is returning to normal.  As long as there were no unexpected complications there are no lasting effects on the body's organs.

Because of how the body processes these drugs and removes them there is no long-term accumulation in the blood stream.  Therefore doing another surgery in a week or two is no more dangerous than doing it in a year or two.  By the time of the second anesthetic event the body has cleared all of the medications and effects of the first surgery to the point of it essentially reacting as if no previous procedure had ever been performed.

Doing multiple surgeries within the same year or even same month is no more risky than doing them years apart.

With that being said, there are certainly good reasons to wait longer.  Though the anesthesia itself may be safe, damaged tissues need time to heal and this can take anywhere from weeks to months.  A surgeon may elect to wait many months to do a second surgery simply so that anything changed, repaired, or removed during the first surgery has a good chance to heal before tissues in that area are stressed again.

When in doubt, ask your vet lots of questions about why they may want to do multiple procedures close together.  But also realize that such things aren't inherently dangerous simply because there is a short amount of time between them.

Tuesday, October 18, 2016

Macbeth: The Triumphs And Trials Of Live Theater

"It will have blood, they say.  Blood will have blood."
Macbeth Act 3, Scene 4

This past weekend I finished up a run of eight performances as Macduff in Shakespeare's tragedy, Macbeth.  I've acted in community theater for several years and this is my third time doing a Shakespeare play (previously having been in Much Ado About Nothing and Romeo And Juliet).  My wife and I are big Shakespeare fans and love the Bard's works, auditioning for them whenever we can.  

Live theater is a lot of fun.  Every night you perform is a new chance to do amazing things.  A good audience will absolutely make you feel energized and can improve your performance.  It's a lot of work, but the payoff can be amazing.  

In one scene of Macbeth Macduff's wife and son are murdered, which drives Macduff to hunt Macbeth for the rest of the play.  My wife played my wife and my daughter played the son (she's young and slim enough to pull it off).  As written this is a very short scene without a lot of drama.  But our director expanded it to give the murder more impact.  Rather than just killing the son, the murderers (who in our version were also the three witches) torture him slowly.  Then instead of just killing the wife she is thrown into a wall and dragged through the audience screaming.  Many people said that they cried after seeing this scene, and couldn't believe how powerful it was.  

Here are a few photos to show what I'm talking about (from a rehearsal, so these aren't the real costumes).

That splash of red on the wall?  That's my daughter's blood.  Or rather, a blood packet that she hides in her hand and squeezes when she is stabbed.  

This show had a LOT of blood!  As we were doing this before Halloween the director wanted to emphasize the horror aspects of the story.  So the witches were portrayed as truly frightening and he designed various ways to have blood spray during appropriate scenes.

While these scenes were very powerful, they were the source of a few of the trials of live theater.  Since my wife was only in one scene, she doubled as the costume designer and helped prepare blood effects backstage.  Her biggest frustration was that the blood got everywhere!  When we first started dress rehearsals most of the shirts were white.  She planned on cleaning them every night but quickly discovered how difficult that was.  So she ended up dying several shirts red to make it harder to see the spots that she couldn't easily get out.  But blood spots somehow ended up on clothing that was never worn during bloody scenes.  I was never involved in any scenes where any blood sprayed, yet somehow I had a few spots on my shirts.  It drove her crazy having to keep the costumes clean with so much fake blood going everywhere.

That blood also ended up on the stage, which made footing potentially treacherous.  In a few performances there was so much blood before one of my scenes that the actor playing Prince Malcolm and I had to be careful not to step in it, yet because the bleeding happened in a previous scene at a different location we also had to ignore the blood since our characters wouldn't have seen it.  One night going off stage at the end of the scene he stepped in a puddle of blood and slipped, almost falling down.

In live theater you don't get retakes!  If you miss a line, miss a cue, or step in blood, you can't yell "cut" and go back to the beginning.  You have to just keep going on and try to make the best of it.  Good actors can cover their mistakes or those of others, and often the audience never knows that a mistake was made. This happened to me during a few performances, especially when I was supposed to be very intense and passionate, yet I usually only ended up mixing up some words.  If you didn't have a script in front of you the average person would never notice.

One of the things I loved most about this show was the fact that I got to have a climactic battle with Macbeth, and my character ends up killing him at the end.  I've always loved cinematic sword fights and our director is also a great fight choreographer.  There were many very intense fight scenes and I was in only one, but it was arguably the best one because it was the culmination of the entire play.  Everything led to that moment.  And it was a blast!

However, as triumphant and exciting as a good stage fight can be, it is also filled with potential pitfalls.  We were using heavy metal swords, and even though they didn't have an edge they could still be dangerous.  We had to practice our moves again and again in order to make it look spontaneous and realistic, yet still be safe.  We also threw punches and kicks, timing it so that it looked like we made contact even if we didn't.  But accidents happen.  During one of the last dress rehearsals a fist grazed my face.  At the time I barely noticed it but a few days later my wife saw that it had developed into a black eye.  A few times on stage either me or the Macbeth actor missed a swing, and we had to try and cover that mistake while still being convincing.  In the opening night performance I stumbled at one point and actually fell down during the middle of our fight.  We couldn't stop, yet we had to be safe.  I managed to scramble back up in time to continue the fight.

Most people seem to think of Shakespeare as boring.  They are probably remembering having to read it in school.  In my opinion, we shouldn't be teaching his plays as literature.  Literature should be read.  Plays should be performed or watched.  There are so many things in a play that don't come across in the written word.  They are only obvious when you have an actor who understands the words and can bring that out with real emotions.  That's how the Bard intended his plays to be enjoyed.

Thursday, October 13, 2016

US Politics Suck....Problems With A Two Party System

Ready for the can of worms to be opened? Because I'm getting ready to talk politics. This has been a rare subject on my blog, and I think the last time I wrote anything on this issue was the 2012 and before that 2008, both during the US presidential election. And you know what? It's that time again!

This year I'm completely fed up with our political system. I hate that we have two parties that so dominate the system they prevent other parties from getting a foothold in the media or elections. I also hate our "winner takes all" and "first to the gate" system where a candidate can claim an absolute win even if they get 50.1% of the votes, and the losing candidates get nothing and no representation of their views. I recently ranted about my feelings on Facebook, and because this is my blog and is about the personal life and views of a veterinarian, I'm sharing it here.

Trump has done many reprehensible things, more than any Republican candidate I can think of in my nearly 30 years of voting. Hillary has been caught in more lies and corruption than any Democrat candidate I can think of during that time. Sure, there have been less than ideal candidates on both sides during that time, and plenty of Democrats with whom I've had significant disagreements on their policies. Heck, I've even been upset at some of the Republican policies, even though I lean strongly Right.

I've never seen such poor choices for candidates in my living memory, even going back to my childhood before I could vote. And the American people agree, with both Trump and Clinton having the lowest approval ratings of any previous candidate.

What frustrates me is so many people still support them! And as far as I can tell, it's not because these are great candidates, but because those supporters won't consider voting for another party. So they are voting for the party regardless of who the candidate is. I see this among both Republicans and Democrats. I've seen memes about each candidate, listing their problems and then concluding with "But their supporters don't care." And that's true of both of them!!!!!

I get upset when I see Republicans going out of their way to defend Trump. Strip away his party affiliation for a moment. Just look at what he has said and done and how he has acted. If he was the Democrat candidate would you still support him? If he had a (D) or even (I) next to his name would you be behind him as much? Because there have been plenty of Democrats who have done things similar to Trump who have been blasted and condemned by the Right. Remember Anthony Weiner?

And Democrats....If Hillary was a Republican would you still be ignoring her lies and mishandling of numerous situations? If her husband was a former Republican president who had been accused of sexual assault on numerous women would you still support her and be okay with her never once denouncing her husband's actions? You've blasted Republicans for less than what Hillary has done.

What I am seeing again and again among friends and in the media is a scramble to defend a given party's candidate. Someone who traditionally votes Republican MUST support Trump because he's the candidate. So they have to find some way to gloss over and ignore his problems, when they would NEVER tolerate the same actions or comments in a Democrat. Now go back to the beginning of this paragraph, replace Trump with Hillary and switch Democrat and Republican....the same statement is true. Members of each party are merely supporting their party, yet in doing so they are complicit in supporting the attitudes and actions of those candidates.

And this attitude among voters is exactly what the elite in Washington want. It's how they trick people into thinking there are only two choices, and thus how they maintain their personal power.

My Republican/Conservative and Democrat/Liberal friends, please be completely honest for a moment. I mean really, really honest in the deepest part of your heart. If I listed the comments and actions of each candidate but you didn't know who they were or what party they represented, would you still feel comfortable supporting them? Republicans, how would you feel if a Democrat governor bragged about trying to kiss married women and "grabbing p***y"? Would you say "well, that's just talk and we shouldn't consider it a problem." Honestly and truly would you be okay with this same thing from any Democrat? And Democrats, if a Republican cabinet member lied about being under sniper fire, lied to the FBI under oath, and simply couldn't remember anything about classified files, how would you react? Would you be okay with these actions and still think they would make a good president?

Character matters. Conservatives have been saying this for decades but now when it's THEIR candidate suddenly it doesn't seem to matter. We should not be looking at which party a candidate belongs to. We should be looking at their actions, words, and character. We can't see into a person's mind or soul, but we can certainly assess how they act, what they say, and the manner in which they conduct themselves. Please, America (and all of my friends), take a moment and strip away the party affiliation for each candidate! Stop buying into the fallacy of there only being two choices! Think about whether or not you would accept the behaviors of your candidate if those same actions were instead coming from their opponent. Judge them not on the letter next to their name, but them as an individual based on their confirmed words and deeds.

Stop voting along party lines! Voting for the lesser evil is STILL VOTING FOR EVIL!!!!!!

Find the candidate that you honestly feel has the BEST character, is the most honest (as honest as a politician can be), has the best integrity, is the most willing to work with those with whom they disagree (which is the only way to get this country moving again), and who has the political platform you can most live with. Vote for this person regardless of which party they belong to.

This is the only way for us, the citizens, to regain the power that we are supposed to have.  This is the only way to get more ideas expressed in the political arena.  And it's the only way for us to break the stranglehold of the two party system.

Monday, October 10, 2016

Vets Get Discouraged Too

Recently I had a very tough case.  A stray kitten about four months old ended up finding a family who took her in.  For the first few weeks she was fine, but then suddenly became sick and lethargic.  They were concerned that she had eaten a mouse that had died of poison.  One of my associate doctors saw her, ran typical tests (fecal, blood chemistries, blood cell count, etc.) and found her essentially healthy with no explanation for her symptoms.  She was sent home for observation.
Two days later she came back and I was working.  The kitten wouldn't stand up and though she was purring she was very weak.  We gave her some fluids and some food, which she ate readily.  The clients declined further diagnostics due to costs, so we observed her.  By the early afternoon she had improved and was standing up some.  But over the next few hours she worsened again.  The owners took her home and she died that night.
I talked to them the next day and because I was so puzzled I offered to do a necropsy (autopsy on animals) at no charge.  They brought her body in which had thankfully been placed in the fridge overnight.  I examined every organ and body system, including the brain, and could find no evidence of trauma, toxins, bleeding, organ abnormalities, or any abnormality whatsoever.  In essence this cat had normal internal structures and no explanation for her illness and death.  We could have sent tissue samples to a pathologist to try and find microscopic explanations, but the client couldn't afford that.
Three days, over $300 worth of testing, and a necropsy.  All without any answers.
I hate these cases.
Believe it or not, sometimes it's hard to figure out what is wrong with a patient.  My human colleagues have the same challenges.  We can run multiple tests and get normal results, yet still have a patient that's obviously not healthy.  Those tests aren't pointless because we can rule out certain possibilities and thus start to narrow down our list of disorders.  But in some cases I am more able to tell the client what their pet doesn't have than I can tell them what it does.
This can be very frustrating for the client, as it was in the case with this kitten.  I completely understand that!  They spend money and time doing what we recommend, and then we come back telling them that the tests were normal and we still don't know what's wrong.  It's not unusual for a client to wonder why we couldn't figure it out.  But that's the nature of medicine.  Sometimes we get an answer on the first set of tests.  Sometimes it takes multiple and increasingly specific diagnostics to get to a final answer, and that takes both time and money.
It's also frustrating for the vet!  I was nearly pulling my hair out the other day trying to figure out what was wrong with the kitten, especially when I didn't get any answers at all on the necropsy.  I went over multiple possibilities, all coming up empty or needing further testing.  Honestly, I was very discouraged by the case because I hate not being able to give an owner some kind of answer.  Even if it's bad news that may result in euthanasia, at least it's an answer and we're not left wondering.
Vets get into this field knowing that we won't make much money.  We do it because we care about animals and truly want to help people and their pets.  We can often take it personally when we lose a patient or can't make them better.  Depression is a big problem in my profession because we do get so emotionally involved yet we can't fix every animal.  We feel pressure from the clients we care about, but even more pressure from ourselves.  All of those years of training and experience, the latest diagnostic tools, but we still come up empty on answers.  "What am I missing?  How can I not figure this out?  How stupid must I be?"  Yes, these are real thoughts that I and many other doctors have had.
Losing a patient or not being able to diagnose an illness isn't something we take lightly.  We don't shrug it off and move on.  We linger over it as we keep running the case through our mind searching for that one clue that we missed.  Then we become incredibly discouraged that we didn't have a solution, sometimes second-guessing ourselves with future cases.
Being a vet isn't easy.  It's more mentally and emotionally draining than many people realize.

Friday, October 7, 2016

First Vet Jobs

Recently I received this email from Maia...

I am a high school student in Colorado. 

I am very interested in veterinary medicine, and have been ever since I was little. Last summer, I reached out to a few of the veterinary clinics local to me, asking about possible volunteer opportunities, and finally found one. I have been volunteering there once a week (6 hours/week) for around four months. 

I read your little "About Me" blurb on your blog, and saw that you got your first veterinary job at the age of fourteen. 

Might you be able to tell me a little more about that? In particular, I am wondering what kinds of jobs in the veterinary field are available for fourteen-fifteen year-olds. 

The first vet clinic I worked at was a relatively new one in our town.  It hadn't been open long and the owner, Dr. John Strasser, was looking for some help.  He already had a receptionist and an assistant, but not much else beyond that.  Since I didn't have any experience I started in the kennels, and that's where I worked for the first few years.

This was definitely not a glamorous job!  I walked dogs outside, cleaned up poop and pee, cleaned kennels and runs, and bathed pets.  I also swept and mopped the clinic, took out trash, and just about any odd, "dirty" job there was.  No, that part wasn't much fun.  But I was working at a vet clinic!  I got to see surgeries.  I saw pets treated for numerous diseases.  I learned how to hold pets for wound care, and various other treatments.  Between being a "super-dooper pooper-scooper" and all-around grunt and "go-fer" I got to see what it was like to be a vet and treat pets.  I got hands-on experience in the profession and started seeing things that would develop me over the years.  Sure, I got lots of feces, urine, blood, and other "unmentionables" on me, but I also gained a lot of knowledge that helped me stay at it for so long.

I also learned a strong work ethic.  My parents always pushed me to do my best and work hard, but having a job at such a young age, and one where I really did have to put in a lot of work, taught me how to be a good worker.  I learned that I would get out of something what I put into it, and that being diligent and responsible would pay dividends over time.  I learned that hard work was always worthwhile, and that there was nothing demeaning about cleaning up dog poo.

It took me a few years to work my way through the treatment area, to the reception desk, and to assisting in rooms and surgery.  I worked off and on for that same practice for 13 years and it played a large part in getting me into and through vet school, as well as helped shape the vet that I am today.  It was an invaluable experience.

Maia, you may have a harder time finding a paying job in a vet clinic nowadays.  Labor laws have changed since the 1980s when I was hired, and liability towards minors is a bigger issue.  Working in a veterinary clinic exposes you to certain diseases and injuries, and many employers aren't eager to take that risk.  My own clinic doesn't hire anyone under 16, and limits what they can do until they are 18.  Other clinics may be willing to hire younger, so look around.  The fact that I started so young was an aberration and shouldn't be seen as the expectation.

I would also have your parents look into volunteer rules.  I don't want someone to take advantage of you and use you as free labor just because you are eager to get your foot in the door of a vet clinic.

Also, look over my blog for questions from students I've answered over the years, starting here.

Tuesday, October 4, 2016

Pokemon As A Veterinary Marketing Tool

Unless you've been living under a rock or don't have access to any form of social media, you are already aware of the recent phenomenon of Pokémon Go.  It became popular faster than any previous mobile game and really took over the culture in Western civilization for a while.  For a while internet searches for Pokémon outnumbered those of pornography (which is what many internet observers use as a yardstick for measuring search volume).  Though the popularity is waning some (mostly due to software issues and problems with game features), it's still something that millions of people play every day.

I'll admit that I'm one of those players (Team Instinct, for those who are interested).  I've never really cared much about the Pokémon card games, video games, or cartoons even though my son is nearly obsessed with them.  But the mobile phone game intrigued me and I downloaded it, quickly discovering that it really was a lot of fun.  I'm not a hard-core player, but I enjoy it and it's been fun using it as a bonding opportunity with my son as we hunt Pokémon together.
So what does this have to do with veterinary medicine?
One of the unexpected yet happy things that has happened with this game is how it has allowed small businesses to market themselves and bring more people in.  If a business is listed as a "Pokestop" they can buy a "lure" in the game which will draw Pokémon to that location.  People want to visit that business because of the Pokémon there which gives that place an opportunity to sell products or services.  Some businesses have advertised discounts to people based on which of the three teams they are on (Mystic, Instinct, and Valor).  All of these marketing tools can be done extremely inexpensively or even free, and considering the millions of people who play the game it can really boost revenue.
Veterinary businesses are not excluded from these tools.  Recently I read an article in a trade magazine that listed several methods of using Pokémon Go to bring in new clients.  Some of those included:
  • Setting lures to draw Pokémon
  • Offering discounts based on who dominates the closest Gym
  • Posting pictures on social media that show Pokémon in the business, especially rare ones (for those who don't know, the game is "enhanced reality", which allows the monsters to be seen in the environment through the camera on the phone)
  • Egg-hatching dog walks (in the game you can hatch "eggs" which give you new Pokémon, but only by walking 2km, 5km, or 10km with the app open)


I've seen various marketing techniques described on several websites, and honestly I think it's pretty interesting.  It shows how creative some people can be, and how a game can be both fun and a business builder.  It also opens the door to brand new marketing techniques that can be used in the future.  I'm sure the creators and fans of the game had absolutely no idea that business owners would use features of the game in this way!  It really shows what people in a free market system can do, and how creative some people really are.
I wonder if I can find bulbasaur or squirtle anatomy and medicine in my reptile text book...

Saturday, October 1, 2016

Nothing Is Risk-Free

About 2 1/2 years ago I wrote a post on the challenges of removing microchips in pets (you can find it here). There have been many comments and some good discussions over the years in that post, though I realize that most of my readers would never go back to an old post just to look at the comments. Many people have the mistaken impression that microchips are likely to cause cancer or serious health problems in pets, and have brought these points up on that post. One of the readers recently made the following comment:

With all due respect Dr. Bern, There are many seemingly innocuous things given to animals and people that can cause injury to those who have no tolerance for it. I knew my cat and I know the chip was causing him problems. I am a vaccine injured adult; but many argue that they are harmless. I also had a severe inflammatory reaction to metal clips placed in my breasts after a biopsy to mark the spot. I know I can't tolerate foreign anything in my body; so why not an animal? They are even more sensitive than most people. I would NEVER inflict that chip into another pet again. My hope is that through these discussions, you'll be aware that it could cause an issue for some animal in your practice. Don't overlook the possibility just because you love the product so much.

They brought up a fairly reasonable point, and one worthy of a thoughtful reply.  I also thought it would be a good topic to bring up as a separate post.  What I have below is an expansion on what I replied on the older blog entry.....

You may not realize it, but there is not a single product, drug, or procedure I do that doesn't carry the potential for some risk. There isn't a single medication or supplement in humans or animal, even over-the-counter ones, that doesn't carry some risk. With every single patient on every single day I have to weigh the pros and cons of every treatment, surgery, and drug that I decide to use. I have to calculate the risk in an individual patient versus the potential benefits. So I am very, VERY aware that ANYTHING I do on a daily basis "could cause an issue for some animal in [my] practice." NOTHING I do, use, or prescribe is completely without risk, no matter how safe it may be for the majority of patients.  We as doctors are trained to watch out for these things and sometimes have to decide to withhold a treatment because it is more dangerous than the disease.

What you may be getting confused on is what we call "idiosyncratic" reactions. These are problems that happen without being expected and without the ability to predict it. Believe it or not, we can't tell whether or not a patient will have an adverse reaction until it happens. I may vaccinate 10,000 pets without any problems at all, and then the next one will have a severe reaction. There is no way that I can tell just by looking at a patient whether or not it will have a reaction. And I can't put a patient at risk for disease by assuming that EVERY patient is that 1 in 10,000 case.  Most of the time if there is a reaction it is an unpredictable one, even if it is in the list of potential side-effects.  Because we don't know which ones will and won't react poorly, we play the odds and handle such problems as they come up.

You were injured by vaccines, and I'm very sorry for that. Does this mean that we should stop vaccine programs across the world that have helped millions upon millions of people and have eradicated some diseases? Because you had a reaction to a vaccine does that mean I shouldn't give them to my children?  No, of course not. We know that virtually all people will be fine after receiving vaccines, and unfortunately there is no way for us to pick out the people who will react adversely beforehand. So we take the chance, play the odds (which are stacked significantly in our favor), and handle the rare bad situation when it comes up.  No medical profession would in good conscience say that vaccines are always "harmless".  But the good ones know that the benefits far outweigh the risks, and the vast majority of the patients will indeed suffer no significant harm.  If someone does have a bad reaction we have to handle that and then flag that individual as someone with whom to be cautious with future treatments of a similar kind.

Can microchips cause problems? Sure. But so can anything else we to or give pets. Will most or even a large minority of pets suffer because of microchips? Absolutely, unequivocally NOT! Millions of animals of various species have received microchips over the last 20 years, and less than a fraction of a percent have had any problems at all. I've known many pets who have been reunited with their owners because they lost their collar but had a microchip. Do you think those owners thought the microchip was worth it? Do we continue to use a product that we know is safe in 99+% of patients? Or do we deny them the possibility of safely returning because of a risk of less than 1%.
If you had a 99% chance of winning the lottery would you spend $50 on a ticket?

I will disagree with the statement "they are even more sensitive than most people".  This is far from the truth and is a poor statement.  Yes, there are SOME things that they are more sensitive to, such as cats with drugs like aspirin or Tylenol, dogs to a component of chocolate, and so on.  But there are plenty of things that they are only as sensitive to as humans, or even less sensitive.  The above quote is a very inaccurate and misleading blanket statement.

Also, I disagree that foreign objects in the body are highly likely to cause problems.  The above reader had complications related to metal clips in her body.  However, the majority of other women haven't had any problems (this goes back to the idiosyncratic reaction).  Many vets use "hemoclips", which are small, staple-like clamps that can quickly close off blood vessels during a surgery.  Those clips stay in the body for the rest of the pet's life, and I've never seen one come back with a problem related to them that required them to be removed. 

Now you might say "well, these things are all sterile and designed to be in the body", and you'd be right.  So are microchips when implanted properly.  But even without sterility, bodies can be tolerant to small objects under the skin.  You might be surprised how many times I and other veterinarians have taken x-rays on dogs and cats to discover pellets, BBs, or buckshot.  Most of the time the owner was never even aware that the animal had been shot!  I have discovered such subcutaneous metal objects literally dozens of times in my career, and virtually every time it was an incidental finding that wasn't causing any problems at all.  In fact, unless there is an obvious abscess or swelling we don't go in and surgically remove them. We just leave them where they are and monitor the pet.  Believe me, those things from a gun are far more traumatic, irritating, and have a higher potential for infection or other than any microchip.  Yet they don't cause problems in the vast majority of patients.
So to summarize, I am not ignoring the possibility of problems, and I'm more aware than you may realize that EVERYTHING I do in my profession has potential side-effects, some of them serious. I'm just saying that we should be realistic and look at the likelihood of whether or not something will happen and weigh that against the potential benefits.  If the benefit is big and the odds are significantly tilted towards there being no serious side effects, we'd really be careless if we didn't do it.