Aeromedix.com - flightBlog - Essentials news concerning safety and medical issues in AVIATION

Aeromedix is pleased to announce that Aeromedix and founder Dr. Brent Blue are featured in the May 2009 issue of Cessna Pilots Association. The article, written by Patricia Luebke, was featured within the ‘Advertiser Profile’ category. You can find the article below or by picking up the latest issue of Cessna Pilots Association magazine.

Aeromedix Wants to Keep You Healthy and Safe

by Patricia Luebke

When Brent Blue introduced pulse oximeters to the general aviation world (along with then-partner Michael Busch of AvWeb fame) in 1995, the device was only available by a doctor’s prescription. As a physician, Dr. Blue was able to prescribe them for pilots. He says, “Pilots never had the ability to determine when they needed oxygen – or even how much they needed when they flew.” The pulse oximeter Aeromedix now offers is non-prescription and designed for aviation use. It gives a pilot an instant read of blood oxygenation so that the pilot can continually monitor himself and be alert for the onset of hypoxia.

Even if you’re not flying at higher altitudes, Dr. Blue believes prudent pilots should check their blood oxygenation. With a variety of factors from age to smoking to sniffles from the common cold, he says that pilots might need supplemental oxygen flying as low as 5,000 feet. Further, Dr. Blue asserts that the FAA requirements for supplemental oxygen were based more on politics and geography than they were on human physiology.

He explains, “In the 1950s when the rules about oxygen were created, oxygen systems were expensive and heavy. The FAA established a politically expedient rule that would allow any private pilot to fly around the country without oxygen. You can get across any mountain pass in the country at 12,500 feet in about 30 minutes under the current rules.” Dr. Blue goes on to say that some pilots need oxygen at 6,000 feet and some don’t need it at 13,000 feet.

Even if you determine positively that you do need oxygen, a pulse oximeter is still handy. Dr Blue says, “With an oximeter, you can adjust the flow rate so you don’t waste oxygen. That way you can use oxygen just when indicated, and you won’t have to fill your tank as often and this can save you time and money.” He receommends that rather than rely on 50-year old rules, you base a decision on your own person physiology, which includes establishing a baseline reading for your home field while still on the ground and make a rule of thumb for when you start using the oxygen. Suggest rules for oxygen use are located at www.aeromedix.com.

The pulse oximeter was Aeromedix’s first product, and as the company expanded, Dr. Blue says, “We kept to aviation safety with medical and safety products.” By the way, Dr. Blue himself is a longtime pilot and proud owner of a 1980 Cessna 340A and currently flies up to 200 hours per year. He says, “I’ve been flying since college. I like to remind people that I was a pilot before I was a doctor. I learned to fly in a Cessna 150 and have flown Cessnas ever since.” He is an ATP, and also has a seaplane and glider rating. A recent project was completing the building of a Murphy Moose, an experimental bush plane that he says, “looks like a two-thirds size de Haviland Beaver.”

Aeromedix also offers digital carbon monoxide detectors for the cockpit. Dr. Blue has a strong opinion on what he calls the “goofy chemical strips” that turn color to warn you of increased carbon monoxide levels. He cautions, “By the time it turns color, you’re already dead.” The model that Aeromedix offers notifies you when the cockpit air has 10 parts per million of carbon monoxide. He adds, “You want to know about it before it gets bad. We have had reports from pilots of some great saves!”

In regard to these two products – the pulse oximeter and the carbon monoxide detector – Dr. Blue feels as both have a big impact on aviation safety since he believes that oxygen and carbon monoxide accidents are under-reported. In fact, he wonders how many aviation accidents whose cause is determined to be pilot error are actually caused by poor judgment brought on by hypoxia or caused by carbon monoxide poisoning.

Dr. Blue says that if you’ve been flying for four hours at 12,000 feet, you may not be as quick at the controls as you need to be if rapid or complex piloting decisions are required. And when it comes to accidents, “You can’t prove hypoxia,” he says. “Sometimes you can prove carbon monoxide poisoning but not hypoxia. I believe these are causes of accidents much more frequently than most NTSB experts believe. Calling everything ‘pilot error’ is just the easy way out.”

Aeromedix offers its own portable oxygen systems which Dr. Blue says is “the least most expensive system available,” as well as a non-pharmaceutical ReliefBand for motion sickness that’s popular with both pilots and passengers. He laughs, “The ReliefBand has saved a lot of relationships” where a pilot’s significant other suffered motion sickness, found relief with this device and became a willing passenger.

Rounding out the most popular products that Aeromedix offers is the spill-proof portable urinal. When Dr. Blue was the official physician for the National Air Tour a few years back, he distributed a supply to the Tour’s pilots and took some ribbing from them. However, Dr. Blue says after a few days of flying, the pilots had changed their minds, having used the product and discretely asked him if he had any extras with him. This particular item turns urine into a gel so it can’t spill and emits no odor. Dr. Blue says, “Yes, those pilots laughed, but then they were asking for more.”

Aeromedix offers a host of other products, for pilot heatlh and safety, as well as a range of survival equipment. Dr. Blue says, “We have great customer service; we ship the same day and have live people on call to answer questions about products.” He wants Cessna Pilots Association members to know that he is actively involved in aviation as a pilot himself. “We are not just selling to pilots,” he says. “We are an aviation-oriented company from a sales point and an action point of view. We want pilots to be safe and happy with our products.”

For more information, to order products or to read the company blog, visit www.aeromedix.com. For questions for Dr. Blue, write him at bblue@aeromedix.com.

The PSA, or prostate-specific antigen, is not an absolute indicator of cancer by any means. I frequently find it elevated in folks and treat them with antibiotics for a sub clinical (non symptomatic) prostatitis (infection) and they drop into the normal range. A lot of urologists do not do this, which really irks me as the decision seems to be one financially based. It can be incredibly problematic for a patient to have a biopsy if they are in fact infected.

What’s more, the rise in the PSA (e.g. going from 1 to 3 in 1 year) is just as or more important than the absolute number.

The real issue is if you get an elevated PSA, have a biopsy, and find out you have cancer, which is early and localized. Let’s say you are 75 years old. The is probably a 90% chance something else is going to kill you before the cancer.

What’s wrong with having the surgery or other treatments? The treatments can have messy side effects from death to incontinence.

Believe me. If you have a elevated PSA, read and talk to more than one doctor. It will be well worth your time.

I get a lot of questions from pilots experiencing problems with their medical exams. Most of these problems could have been solved if they had chosen their Aviation Medical Examiner (AME) correctly.

For instance, look at this excerpt from an email response to a pilot with a medical issue I sent out recently:

“You should be yelling at XYZ company’ help get your medical (name withheld to protect the guilty). You paid them money for a job they are not doing. They should have insured that all the medical documents were sent together by a service which requires a signature for receipt (e.g., FedEx) and then made sure you were inline for the review by the cardiologist. I still do not know why people waste their money with companies who promise to help pilots get their medicals. Your AME should have done all this. He is the best source for calling OKC and getting status information on your exam. If your AME will not do that, I suggest you find someone else the next time.”

Select your AME carefully. It is not much of an issue if you are totally healthy; however, if you do have a medical problem take some time to investigate. First of all, ask the pilots around your local airport for recommendations—especially pilots who may have had medical problems. (You do not have to ask which pilots have had medical problems, just ask the old ones!) AMEs who get good recommendations for having gone out of their way to help someone with a medical is great reassurance.

Second, make sure the AME is a pilot. You can do check this out at the FAA database (http://www.faa.gov/pilots/amelocator) where the pilot ratings are listed for each AME.

Why a pilot? There are several reasons. One is that an AME who is a pilot knows how important the ability to fly is for each of us. They generally are more interested in aviation, understand what it takes to be in the cockpit, and will go the extra mile for a pilot who needs help with medical problems that threaten his ability to fly.

Although there are exceptions, non pilot AMEs are using the status to build their practice. Being an AME may be a pain for a physician because of the time it takes for the exam, the data input of exams, keeping up with FAA regulations, and the every-three-year required classes. Most pilot AMEs are doing it as a service and because it keeps them involved in the pilot community. A non pilot AME may be interested in aviation but given the hassle, bringing cash patients through the door is a more likely scenario.

How does the AME make a difference? There are many ways but willingness to spend time is the most important way. When there is any medical issue on a pilot medical application, the AME can deal with it in several ways. For instance, if a pilot has new onset hypertension, the AME can make sure he has the proper documentation from the treating physician or have the pilot get the proper documentation. The AME has 10 days to submit the information so the pilot has 10 days to obtain it. With the proper documentation of good blood pressure control and no side effects from the medication, the AME can issue the medical immediately.

However, if the AME is not paying attention he can grant the medical without the paperwork and the FAA will contact the airman and request all the information.

Even the FAA does not like this way of conducting pilot medicals because the AME is not doing what they are suppose to do and is creating unnecessary work for the FAA.

The worst case scenario is that the AME defers the medical. This saves the AME a lot of time because he just says to the pilot that he has to send everything into the Regional Flight Surgeon or OKC and just checks a box on the form. Easy for the AME—a world of paperwork for the pilot and FAA even if the pilot was deferred inappropriately. (Fortunately, the FAA is cracking down on AMEs who defer inappropriately just like they have on AMEs who grant medicals that should have been deferred.)

There are many cases which absolutely require deferment but the right AME can help here as well. A pilot who has had a heart attack will require review by the FAA for the 1st application after the event. The AME can help by making sure the pilot has all the appropriate paperwork and records for the application. The AME should submit the exam with all the paperwork in the same package and send it to the FAA via a “signature required” service. This insures that the FAA receives all the required paperwork and everyone knows what date it landed at the FAA.

If records and testing are submitted separately, there is no one checking off when the file is complete. A file ready for review may wait until the pilot or AME calls and asks if the file is complete. This is a waste of time for everyone and a good AME will not let this happen.

For renewals, the FAA allows AMEs through their AASI (AME Assisted Special Issuance) program to issue medicals for stable conditions on the spot. The pilot needs to READ THE FAA LETTER which accompanies his initial certification for what testing and reporting will be necessary for renewal and when that testing should occur. If the pilot brings the proper renewal documentation to the AME and it shows a stable condition, the AME can issue the medical right then and send the paperwork into the FAA for review after the fact. Unfortunately, there still are Medical Examiners out there who still do not know how this program works.

Brent Blue MD is a Senior Aviation Medical Examiner in Jackson Hole, Wyoming, who flies a Cessna 340 and just finished building a Blue Bear (a Murphy Moose modified for safety). He was the team physician for the US Aerobatic Team for the 1994 World Competition in Hungary and has served on the EAA’s Aeromedical Council. He also owns Aeromedix.com which specializes in medical and safety products for pilots, their families, and their dogs.

Aeromedix was founded to introduce portable, economical pulse oximeters to general aviation. Prior to this advanced equipment, pilots were at the mercy of the FAA regulations to determine when and how much oxygen to use. Those regulations, originally developed in the 1950s, were based mostly on politics and economics and minimally on human physiology. Basically, the 12,500 and 14,000 MSL rules were instituted after the GA lobby convinced the FAA that anyone should be able to fly a GA airplane anywhere in the US without supplemental oxygen. Thus, this 12.5 for 30 minute rule made it possible for any pilot to fly across any mountain or mountain pass without the need for what was then, heavy, expensive oxygen equipment.

What we now know is that some pilots need oxygen at 8,000 feet and some younger, healthy ones, who live at 6,000 feet, might not need oxygen till much higher. Pulse oximetery gives a modern determination of when and how much oxygen a person needs. No more guessing (more about pulse oximeters later).

One caveat before I get into oxygen systems—everyone who flies high and certainly anyone who flies over 18,000 feet needs to undergo high altitude training in an altitude chamber. This is not for the commonly held reason that it teaches the pilot how to recognize hypoxia in their system. That is hog wash. The basic problem with early hypoxia is that it impairs cognitive thinking. No one who gets goofy is going to know when they are getting hypoxic and needs supplemental oxygen.

The purpose in altitude training is to prove to pilots that they too can get goofy when hypoxic. The best chambers video this display of hypoxic effects on each participant so when back to normal oxygen levels, the pilot can see exactly how dumb they got. Convincing each and every pilot that they too will be affected is the important part of this training.

There are many types of oxygen equipment but the bottom line is oxygen is oxygen. Probably the most significant issue for pilots is the hassle of filling the oxygen, how big a tank to buy, and whether conserving equipment is necessary which is based on the prior two issues.

Since the 1960s, all oxygen sources have been from liquid oxygen. There is no difference between aviator’s and medical oxygen. When oxygen was first used in hospitals, the gas was humidified in the tank which is a problem for aviation because water will freeze in oxygen plumbing in cold, high altitude aircraft environments. Since medical oxygen is humidified after it leaves the tanks, this is no longer an issue. However, getting something taken off the FAA regulation books requires undue time and energy so everyone uses whatever oxygen they can find and no one apparently cares. If you truly get “aviation” oxygen, you will find the only difference is that it is tested for water and is more expensive.

First, let me address built in oxygen systems. When an unpressurized aircraft is certified with oxygen, the oxygen system delivers oxygen at a flow rate which is set for the service ceiling of the aircraft. The FAA rule is 1 lpm for each 10,000 feet. If your turbo aircraft is certified for 25,000 feet, your oxygen system would deliver 2.5 lpm regardless of whether you were flying at 15,000 or 20,000 feet. (One disclaimer, there are some aircraft which have automatic pressure controllers but few work properly.) This is a true waste of oxygen. Although oxygen is dirt cheap, if you have to fill at an FBO, the mark up is ridiculous and you are supposed to have an A&P sign off the fill. Most people who have built in systems and use them frequently have gone to filling their systems themselves using readily available hose kits which fit large H cylinders which they keep in the hangar. Not quite legal but I have never heard of anyone being busted for it! Besides, you can always have your friendly A&P sign it off.

A big improvement for the built in systems was the Nelson flow meter introduced in the 1970’s which was essentially a medical flow meter with settings in thousands of feet instead of liters per minute (lpm). The pilot just dialed 15,000 feet into the device which had a floating metal ball and they received the FAA required 1.5 lpm and saved 1 lpm over the preset flow the unadulterated aircraft systems would have given them. These style flow meters are readily available from Aeromedix and others. Another improvement was the FAAs decision to allow the use of nasal cannulas instead of masks up to 18,000 feet. This allows the use of oxygen saving cannula and increased comfort (translates in to more willingness to use). More on cannula and mask later.

Pulse Oximetry

Pulse Oximetry is the biggest advance in oxygen use in aircraft since, well, the use of oxygen in aircraft. It brings the use of oxygen into the 21st century.

Pulse oximeters measure the oxygen saturation in the blood. They do this by comparing the red pulsation of ones pulse in the finger to the background red between pulses via a special red light emitted from the unit. Via a complicated formula embedded in a microchip in the unit, it calculates oxygen saturations. This system works with almost every finger but is impaired with black or some other deep colored nail polish, people with low blood pressure, cold fingers, Reynaud’s syndrome, and a surprisingly few other situations.

Normal saturation at sea level is 95 to 100%. In Jackson Hole, at 6,200 feet, normal is 90 to 95%. When and how much oxygen to use is an interesting question. There are no FAA recommendations based on oximetery. However, when we introduced pulse oximetery to aviation, we did some physiological testing and have made the following recommendations.

The pilot and passengers should take note their saturation levels at their home airport (obviously different if they live at sea level versus a ski town). We recommend that the person “should” use oxygen if their saturation drops five points below their home airport saturation. We recommend that the person “must” use oxygen if their saturation drops ten points below their home airport saturation. Now some pilots will require oxygen at 8,000 feet and other might not need it to much higher. Once the decision to use oxygen is made, the level should be titrated by adjusting the oxygen flow to bring the saturation close to the home field levels. 

An important caveat to remember about pulse oximeters is one thing fools them—carbon monoxide (CO). CO actually falsely increases the saturation reading. It is one but not the only reason everyone should have a low level carbon monoxide detector. in their aircraft—high altitude flying or not. This silent killer is responsible for accidents every year and carbon monoxide accidents are completely preventable.

Portable Systems Fall between Cracks

Portable Systems fall between the regulatory cracks. Aviation systems are not regulated by the FDA and portable systems are not regulated by the FAA. For the most part, all oxygen equipment made in the US is of superior quality and can be trusted. Tanks do need hydrostatic testing every five years but that is about all the hassle besides filling the system.

Tanks can be filled at most medical, welding, or other gas suppliers. Some require a prescription but this is as variable as the TSA inspectors at airports. (I will be happy to provide a prescription for any of our customers.)

Generally the size of the tank is dictated by the normal mission length and altitude, the number of passengers usually taken, and the space on board the aircraft. Tanks come in different lengths and diameters and there never is a perfect choice. Systems have built in gauges showing their fill level and require a second regulator stage which lowers the pressure to the flow meter (if not built into the second stage itself).

Cannulas

One of the newest and cheapest oxygen saving devices to hit the market is the Oxymizer Cannula. This cannula has a thicker section which sits on the upper lip under the nose which contains a “bag” which collects oxygen during the exhalation and pause part of the breathing cycle. The normal breath cycle is inhalation, exhalation, and pause. With normal cannulas, the oxygen flowing during the exhalation and pause part of the cycle is wasted. With the Oxymizer cannula, the oxygen flow during these portions of the cycle is captured and the bag collapses during the inhalation portion of the cycle giving the “stored” oxygen to the pilot. This allows for lower oxygen settings to obtain the same inhaled amount of oxygen. This cannula can increase the oxygen tank duration up to 50%. For those who dislike the larger nasal portion under the nose, there is a pendant style Oximizer which has a “remote” storage “bag” and works the same way. We combine the pendant with the OxyArm cannula for a cross between convenience, comfort, and increased oxygen duration.

Although the FAA requires the use of oxygen masks above 18,000 feet, I have concerns about that. Depending on the individual, they may or may not be able to obtain a high enough saturation in the flight levels. (Anyone who flies unpressurized aircraft in the flight levels must have an oximeter. It is crazy to fly without one.) My concern with masks is that you have to take it off to drink water or to eat (hopefully, you have a built in mic). In the flight levels, even during a 15 second period of taking off the mask to drink some water, a pilot can get goofy and forget to put the mask back on. One great thing about nasal cannula is that they are kept on for eating and drinking. Besides, I have never seen a FAA inspector at 18,000 feet.

Find out more about our Oxyarm with Oxymizing Pendant Conserver here at Aeromedix.com

The Cirrus Problem

For Cirrus pilots only: The Cirrus Pilot Operating Handbook has presented an unusual problem dealing with oxygen. Cirrus has designated a specific portable system for the aircraft to be legal for oxygen use. This requirement is for the aircraft to be legal. For the pilot to be legal, they can use any source of oxygen. What this means is that to be totally legal, you must have the Cirrus required system on board but you can bring along any system you want to provide the oxygen. The only place you would have trouble with not having the designated system on board would be if you were ramp checked and told the FAA examiner you had just been flying above 12,500 feet MSL for more than 30 minutes or above 14K at all. Don’t you dare!

I received my RSK Mk1 as a Christmas present from my wife in December 2005 (after me hinting a few times… ok, a lot). This was my first knife with the Axis lock, and my first knife with S30V steel, so I was excited on three counts. I was looking forward to the Axis lock and the S30V due to the hype surrounding both; but more importantly, the blade shape itself caught my eye as soon as I saw it. I have had it now for almost 3 yrs and during this time I have asked it to do everything that a folding knife should. I have taken it with me on every trip that I have been on since I got it. It has been with me in every type of weather, and temperatures from -30C to +30C.

During a trip to the Maritimes in February 2007, the RSK Mk1 saw action in the kitchen preparing venison stew for me and two friends; I found that the high sabre grind made it great for slicing and preparing our meal in general. On the same trip, we ventured out on the frozen Atlantic Ocean in -30C weather, to reach a nearby island which had a seal colony. While I was out on the ice, I had no trouble using the axis lock.

On my most recent trip with the same two friends last fall, we were fortunate enough to get a whitetail deer, and again the RSK Mk1 came through with flying colours. The RSK Mk1 was used to dress and skin the whitetail deer, and out of all the knives that we had at the time, we all agreed that it was the best by far.

Over this last winter, the RSK Mk1 was with me on all of my hikes, no matter what the weather, I knew I could rely on it. I find the Axis lock great for the winter months here in Canada, as I can manipulate the lock without removing my gloves. This knife is totally reliable in all weather conditions, and I have carried and used it in temperatures ranging from -30C to +30C, without any problems.

In order to be totally honest with my review, I will mention that I did have some chipping issues initially. I found that the factory edge was too thin, and under some light use (food prep.), the blade did chip slightly. I used my Lanskey sharpener and re-profiled the blade to steeper angle and I have not had a problem with it since. I have used it for everything from peeling apples for my son on Saturday morning hikes, to skinning a whitetail deer while on a trip with friends.

More recently, it was with me on some rainy summer hikes, and after a quick rinse the RSK Mk1 looked brand new, and once again up to any task.

 Overall, I am still as pleased with my “Ritter Grip” as the day that I got it. It has never failed me and I find it totally reliable.

James Gamble (J_Roc on Bladeforums)

Ottawa, Canada