What is a Pressure Ulcer (AKA Pressure sore)?

shutterstock_89421025bed-soresPhoto credit:  http://diseasespictures.com/bedsores/

A patient came in to see me today with a sore on his heel that’s been bothering him for the past few months.  He’s diabetic and has lost feeling in the bottom of his feet.  He’s had these pressure sores in the past but has trouble getting them to heal up.

Pressure sore:  Areas of skin that have been damaged by pressure such as sitting or lying in one position for a very long period of time.  They can also be called “bedsores.”  The are more commonly found in areas of the body where the bone is near the surface of the skin such as on the hips, elbows, ankles and back/buttocks. The skin and soft tissues become damaged because not enough oxygenated blood can get to the area to promote healing usually due to the compression of the damaged skin and soft against hard bone tissue.

Appearance:  The sores change in the way they look depending on how long they’ve been present and how much damage has been done.  In the beginning, the sore appears as a small red patch of skin, and if not treated, the skin will break down and cause a hole or crater to form (we call this an ulcer).

Stage 1:  The skin is intact without ulcers but when you push on the skin it does not change colors to indicate good blood flow.  Usually, healthy tissue will be pink and when you push on the area with your finger you can notice it will become less pink and in a couple seconds the pinkness will return.  This does not happen in the damaged skin at this stage – it may have a darkly pigmented color.

Stage 2:  There is an open, shallow ulcer with a red-pink color at the base of the wound.  Sometimes there may be blisters present which are either intact or ruptured.

Stage 3:  Structures beneath the skin such as fat may be exposed but at this stage, you should not see bone, tendons or muscle tissue.

Stage 4:  Structures beneath this skin including bone, tendon and muscle may be seen in the bottom part of the ulcer

People at Risk:  Some patients are more at risk than others of getting pressure sores.

1)   Patients who cannot move very well because they have a medical problem.  These people may sit or lay in one position for a long time.  They need help to move to a different position so that the skin doesn’t form sores.

2)   Older people are more prone to pressure sores because they often don’t move around as much and their skin is more fragile and thinner than a younger person.

3)   Patients who have diabetes or nerve problems in their feet may not feel when a small pebble or area gets into their shoe or pressure pushes on the foot causing injury.

4)   Patients in the hospital or nursing home are at especially high risk for many of the factors noted above – increased age, decreased mobility, and other complicated medical problems.

Prevention:  Some things can be done to lower the chances of getting pressure sores

1)   Repositioning the patient’s body every two hours so that they are not lying on one area where the skin is being crushed, pinched or pressure is building

2)   Putting pillows between the ankles and knees to decrease the pressure on the skin over these boney areas

3)   Raising the head of the bed when the patient is lying on their side to decrease the pressure on the hip bone

4)   Getting special foam or soft mattresses that decrease the pressure on the areas of the body that have the most pressure on them

For patients in wheelchairs:

1)   Use a special cushioned seat if possible to prevent pressure on the sacrum

2)   Every hour tilt forward or to the side to release pressure on the seat

3)   If ankles or heels press on the chair, use foam padding to protect against sores

4)   Check skin regularly for signs of pressure or ulcers

Treatment:  Pressure sores are treated differently depending on the stage of ulceration and how severe the damage to the skin is.

1)   If there is mild erythema, the treatment is generally off-loading the area but decreasing the amount of time that this area is compressed by body re-positioning, and/or using pillows to cushion the area.  We also use transparent films over the ulcers to protect the areas.

2)   In patients who have diabetes, adequately managing blood sugars to keep them under good control is very important.  Elevated blood sugars impede wound healing.

3)   If there is dead or dying skin or soft tissues, this often needs to be removed to help prevent infection.

4)   Special bandages may be needed to keep the healing tissue moist but prevent tissue maceration (from being too moist). Sometimes the dressings that we use to treat wounds can be very expensive.

5)   Antibiotics may be prescribed if there is a wound infection

6)   Medication for pain may also be prescribed

There are some tools to score the pressure and grade the healing process.  These are helpful for patients who come back for repeat visits to wound care clinic or their primary care provider and there is a need to grade the healing by giving them a score.  Some clinical features that are examined include:

1)   Amount of Exudate

2)   Skin color surrounding the wound

3)   Peripheral tissue swelling

4)   Peripheral tissue firmness around the wound

5)   Amount of granulation (healing) tissue

6)   How much epithilization is present

It’s important to optimize the nutritional status of patients with wounds.  Particularly for patients who have Stage 3 and 4 ulcers, they need enough protein and calories to help heal these wounds.

This document is for informational purposes only, and should not be considered medical advice for any individual patient.  If you have questions please contact your medical provider.


I hope that you have found this information useful.  Wishing you the best of health,

Scott Rennie, DO

Blog: https://doctorrennie.wordpress.com


A Discussion About Wilderness Medicine – Hawaii Public Radio January 6, 2014

Here’s a link to a discussion I had with Dr. Kathy Kozak about Wilderness Medicine on Hawaii Public Radio on 1/6/14.


Listen Here:


Happy New Year,

Scott Rennie, DO


Trendy Drugs of Abuse

shutterstock_10131886Healthcare professionals across the country are seeing a new and alarming trend in drug abuse.  As doctors and parents, it is important that we are aware of these substances and understand how patients who use them may present.

1)   Dextromethorphan (“Robotripping”):  Street names are DXM, CCC, High C and skittles.  These are most commonly seen in boys between 10-14 years of age.  Dextromethorphan is commonly found in cough syrups such as Robitussin and is ingested at about 25 times the therapeutic dose. It causes a dissociative anesthesia similar to PCP.  They are often other ingredients in these common cold medications such as Tylenol and chlorpheniramine that can cause harmful effects on the body including permanent liver damage.  The effects of the dextromethorphan can include decreased alertness and transient hallucinations and risk for trauma due to the dissociative effects.

2)   Bath Salts (MDPV):  These are not actual bath salts, but designer hallucinogenic amphetamines or a newer version of “ecstasy” (MDMA).  Common names on the market now include “M-shine” and “hooka cleaner.”   The core substance is cathinone (from the khat plant).  Patients often present with increased reflexes, teeth grinding (bruxism) and involuntary muscle contractions (clonus).  They can have an increased heart rate and may have seizures and can exhibit psychotic behavior or paranoia (that may last for days).  Other worrisome problems associated with bath salt use include running a very high fever, forming abnormal blood clots in the legs or lungs, and liver failure.

3)   Jimson weed (Thorn Apple):  Commonly found growing in back yards, each plant contains seed pods with numerous seeds. Each seed contains a varying amount of the drugs atropine, scopolamine and hyoscyamine.  Eating seeds from one plant may produce a “mild trip” while ingesting seeds from another plant may contain 10-50x the amount of these drugs and produce skin redness, dilated pupils, delirium, urinary retention, decreased gastrointestinal motility and rapid heart rate.

4)   Psilocybin mushrooms:  The spores of the parent plant are harvested and are often distributed by gluing the spores to paper and then sold as “art.” The spores themselves do not contain the hallucinogen.  These are typically sold with a 10-mm syringe and a broth solution. Psilocybin mushroom spores are legal to possess in every state in the United States, except California, Georgia, and Idaho. This is because it is psilocybin and psilocin (the active chemicals in psychedelic mushrooms) which are specifically listed in Schedule I, not the mushrooms themselves.

5)   New marijuana drugs (THC homologues):  Street names include “spice” and “K2”.  Often sold in combination with herbs for smoking.  These are unregulated herbal substances which are often mixed with alcohol or acetone and sprayed on a plant which is then dried and sold.  A single joint contains much higher doses of THC (300mg) than traditional THC.  Clinical effects may include red eyes, rapid heart rate, dry mouth, and perceptual changes.  Agitation, hallucinations and displaying behavior that may lead to trauma.  Synthetic marijuana can also cause seizures, or acute psychotic episodes that can lead to suicidal thoughts.  Other problems such as chest pain, psychological dissociation and panic attacks may occur.  Sometimes the synthetic marijuana that has been sprayed on plants is also combined with formaldehyde (solvent containing PCP) that causes the user to present as acutely psychotic and violent.  Most urine drug screens unfortunately do not detect these substances.

6)   “Pharming, bowling or fruit parties”:  This is a practice where teenagers get together and bring samples of medication that they get from their home (most commonly from their parents’ medicine cabinet).  All samples are placed in a bowl and pills are ingested randomly.  Overdoses on medications for diabetes, high blood pressure and heart problems are common in addition to possible respiratory depression and even death from narcotics, or benzodiazepines or the mixture of multiple substances.

7)   Soma Coma:  Also called “Trinity” if mixed with other drugs.  Soma (carisoprodol) is a non-scheduled drug that is marketed as a muscle relaxer.  It is very similar to a benzodiazepine such as Valium and heavily abused.  It is a heroin substitute when combined with other drugs and its effects are very unpredictable and may predispose the individual to injuries from falls or other trauma.  Many of these users have a history of heroin abuse.

8)   Salvia divinorum:  This is a mint plant common in Mexico.  It is dried and concentrated before being sold, often in online tobacco shops. The salvinorin A contained in the plant is a psychoactive chemical.  It is usually ingested by smoking in a water bong.  Produces a trance-like high for 5-10 minutes.

9)   Alprazolam:  Abuse is on the rise as this medication is commonly used as a “downer” after cocaine use.  Because of its characteristic shape, street names including “candy bars,” “coffins,” or “french fries” may be used.  Pills are swallowed, crushed and snorted.

10)  Cocaine:  Because of the expense, not much cocaine sold on the street is pure. In fact up to 30-40% of some samples contain a common medication used to treat worms in veterinary animals. Highest use among those 18-25 years of age.  Patients who use cocaine may present to a hospital or clinic having a high fever and have low blood cells or platelets, and have red spots on their nose or ears. Cocaine also increases the stickiness of platelets and therefore increases risk of heart attack or stroke. Look for blisters on the thumb and index finger of the dominant hand and scabs or burns around the lips.

11)  Methamphetamines:  After marijuana, it is the most widely abused drug worldwide.  Approximately 5% of the US population has used methamphetamine, with an estimated 500,000 people using the drug in a given month.  It may be synthesized via simple reactions using readily available chemicals and over-the-counter cold medicines, such as Sudafed.   May be ingested orally, rectally, vaginally, be injected, inhaled, or sniffed.  The effects are stronger and last longer than cocaine.  In fact, the prolonged duration of action of methamphetamine (approximately 20 hours) helps differentiate it from cocaine (duration of action 30 minutes) and PCP (duration of action less than 8 hours).  It causes rapid physical deterioration, weight loss, and poor dentition (“meth mouth”).  Life-threatening intoxication is characterized by high blood pressure with rapid heart rate and severely agitated delirium, fever, metabolic acidosis and seizures.  Medical providers should consider diagnosis of methamphetamine intoxication in any sweaty patient with high blood pressure, rapid heart rate, severe agitation and psychosis.  Acutely intoxicated patients may become extremely agitated and pose a danger to themselves, other patients, and medical staff.  Symptoms of methamphetamine withdrawal may develop within hours and typically peak within 1-2 days, and most often decrease within 2 weeks.  During the acute withdrawal period (“the crash”), signs and symptoms may include restlessness, the inability to experience pleasure, fatigue, increased sleep, vivid dreams, insomnia, agitation, anxiety, drug craving and increased appetite.  The prolonged withdrawal phase can last for up to 3 weeks and can include insomnia or even increased sleep, appetite changes, depression and possible suicidal thoughts.

12)  Inhalants (poppers, snappers, rush):  The use of these substances usually decreases as the individual grows older.  Can cause a rapid high, drowsiness, lightheadedness, agitation as well as belligerence, impaired judgment, balance problems, and addiction.   These inhalants may include halogenated hydrocarbons (butane), VCR head cleaner, whipped cream (contains nitrous oxide), colored spray paint (gold color is most popular), amyl and butyl nitrates (poppers, snappers, rush).  “Sudden sniffing death syndrome” is a worrisome problem.

13)  Opiates:  These are also commonly called narcotics (heroin, Demerol, morphine, codeine, fentanyl, oxycodone, hydrocodone, and methadone).  Patients who overdose are often sleepy and have a decreased respiratory rate, decreased gastrointestinal motility, urinary retention and pinpoint pupils.  As a medical provider it’s important to strip an overdosed patient and look for fentanyl patches on the body, but be careful of possible uncapped needles or syringes in the pockets.

There are an increasing number of patients being diagnosed with hepatitis C linked to heroin and other opioid use and that rate is expected to continue increasing.

Street Price:  Vicodin (hydrocodone/Tylenol) is a prescription medication with a street value of $5/pill depending on the geographic location where it’s purchased.  Percocet (oxycodone/Tylenol) or OxyContin sells for about 50 cents to $1/mg but again this varies depending on geographic location and how much is purchased. Buprenorphine/naloxone (Suboxone) which is often prescribed to patients who have a narcotic addiction sells for $5-$20/pill on the street.

Patients presenting to the medical clinic may present in the state of overdose, drug-seeking or withdrawal.  Treatment of overdose may include the use of naloxone.  Narcotic withdrawal symptoms may occur on the first or second day of being without the drug.  Patients may present with goose bumps (where the saying “quitting cold turkey” came from), patients on the third day may be on the floor flapping about with muscle cramps or kicks (i.e. “kicking the habit”).  Other symptoms include anxiety, insomnia, yawning, tearing, sweating, runny nose, all over muscle aches, nausea, vomiting, diarrhea, hot and cold flushes, muscle twitches, abdominal cramps.  Onset of symptoms usually occur within 8 hours of last use with a peak in 2-3 days.  Treatment of withdrawal symptoms may include clonidine, ibuprofen, Benadryl, Phenergan, or Imodium.

It is important for medical providers, parents, law enforcement and teachers to be educated about drugs of abuse that our patients are using and be able to recognize the symptoms of intoxication, drug-seeking or withdrawal and treat our patients appropriately.  The first step in helping protect our patients is learning about some of the drugs of abuse, and signs and symptoms of abuse.

This document is for informational purposes only, and should not be considered medical advice for any individual patient.  If you have questions please contact your medical provider.


I hope that you have found this information useful.  Wishing you the best of health,

Scott Rennie, DO

Blog: https://doctorrennie.wordpress.com



Clinical experience with and analytical confirmation of “bath salts” and “legal highs” (synthetic cathinones) in the United States, Clin Toxicol (Phila), 2011 Jul; 49(6):499-505

Severe toxicity following synthetic cannabinoid ingestion. Clin Toxicol (Phila), 2011 Oct;49(8):760-4

White, Suzanne R  (2011, November) Current Trends in Drug Abuse, Lecture Detroit Trauma Symposium, Detroit, MI.

Kloss, Brian T (2011, June) Drugs of Abuse Seen in the ED, Lecture – Impact 2011 AAPA Annual Conference

High Blood Pressure (Hypertension) – A discussion about the condition, causes and treatment options

shutterstock_117887302What is blood pressure anyway?  Blood pressure is a measure of the force of the blood against the walls of your arteries. Blood pressure readings include two numbers, such as 120/80 (say “120 over 80”).  The first number is the systolic pressure and is the force of blood on the artery walls as the heart pumps.  The second number is the diastolic pressure and is the force of blood on the artery walls between heartbeats, when the heart is at rest.

What is hypertension/high blood pressure?  Your blood pressure normally goes up and down depending on what you are doing. You’ve probably heard that a normal blood pressure is less than 120/80 but it is normal for it to go up when you’re exercising or under stress.  It’s normally higher for example when you’re exercising than when you’re sleeping.  If you’re rushing to make it to your doctor’s appointment, it might be higher when it’s measured in the doctor’s office then when you’re relaxed right before you go to bed. Despite what a lot of people think, high blood pressure usually does not cause headaches or make you feel dizzy or lightheaded.  It usually has no symptoms, but it does increase your risk for heat attack, stroke, kidney and eye damage.  The higher your blood pressure, the more your risk increases. Your doctor will probably look at several variables when trying to determine whether your blood pressure is elevated abnormally and whether your blood pressure needs to be treated.  If you have diabetes, kidney disease, an aneurism or if you’ve had a heart attack or a stroke we usually try to keep the blood pressure lower than for other patients because they are at higher risk of developing additional health related problems if their blood pressure is high.

If a patient is normally healthy without any health related problems, we usually don’t consider them to have hypertension unless their blood pressure is 130/80 or higher – stage 1 hypertension based on Guidelines released in November of 2017.

Guidelines released by the American Heart Association and American College of Cardiology in November of 2017 classify blood pressure in the following categories:

  1.  Normal <120/80
  2. Elevated:  Systolic between 120-129 and diastolic less than 80
  3. Stage 1: Systolic between 130-139 or diastolic between 80-89
  4. Stage 2: Systolic at least 140 or diastolic at least 90 mm Hg
  5. Hypertensive crisis: Systolic over 180 and/or diastolic over 120, with patients needing prompt changes in medication if there are no other indications of problems, or immediate hospitalization if there are signs of organ damage.

Why should you care if your blood pressure in high?  Most of the time when people have high blood pressure they don’t have any symptoms so they aren’t even aware that it’s elevated!  High blood pressure is sometimes called a “silent killer” because even though you don’t have symptoms from it being elevated, it can do damage to the arteries in the heart, brain, kidneys, eyes and other organs.

Men are often most interested to know that having hypertension can cause a form of sexual dysfunction called erectile dysfunction (ED).  That’s right, if your blood pressure is elevated, your sex life may be negatively affected as a consequence.  Read my article on male sexual dysfunction in men here.

It may take years to develop symptoms from this damage but it is usually permanent and can make patients more likely to have a heart attack or stroke, kidney damage (sometimes requiring dialysis), vision problems, and even lead to early death.

Some patients might not have thought about why they would want to stay healthy, so I usually ask them to make a list of what’s important in their life.  For some people it’s important for them to be alive and healthy so they can spend time with their family members (wife/husband, children, siblings, pets, etc.)  Some people enjoy traveling and they may not have considered that it’s much more difficult to travel if you have problems with your heart, brain, kidneys or eyes for example.  I think it’s important to think about what your short term and long term goals are, and use this as motivation for keeping healthy.

Who is at risk?  High blood pressure is a very common problem!  Elevated blood pressure is more common as we get older but can affect anyone.  Among people over age 60, hypertension occurs in 65 percent of African-American men, 80 percent of African-American women, 55 percent of white men, and 65 percent of white women.

I’ve had patients who are children with abnormally elevated blood pressures.  Oftentimes high blood pressure runs in the family, so if your father, mother or siblings have hypertension it’s important to be aware that you are at higher risk of developing hypertension yourself.  High blood pressure is also more common in people who have diabetes, drink more than two alcoholic drinks/day, are overweight, eat an unhealthy diet or don’t exercise regularly.

If you have sleep apnea, you are also at greater risk of high blood pressure.  Until correcting the sleep apnea, it may be very difficult to control your blood pressure.

High Blood Pressure Treatment:  There are certain lifestyle modifications that can help get your blood pressure in the normal range and also medications that your doctor might prescribe.  Usually a combination of both medications and lifestyle changes achieves the greatest success in achieving a blood pressure that is within the healthy range for you.

Lifestyle modifications:

1)     Reducing the amount of salt in your diet

2)     Losing weight if you are not at your goal

3)     Avoiding excessive amounts of alcohol

4)     If you smoke, decreasing or stopping

5)     Exercising for at least 30 minutes on most days

Reducing sodium intake is important because with increased salt (or sodium chloride) intake from food that we eat, our bodies naturally absorb more wate.  The increased water absorbed into the body then contributes to an increased amount of fluid in the blood vessels and heart and that in tern leads to hypertension.  Diuretic medications (discussed below) work in almost an exact opposite way to decrease the amount of salt and water in the bodies and lower blood pressure.

Medications:  If lifestyle changes alone are not successful in getting the blood pressure under control, your doctor may prescribe certain medications to help decrease the strain on the heart and arteries. The constant stress from the elevated blood pressure that may lead to organ damage if not treated adequately.

With such a variety of blood pressure medications available, medical providers try to make the best decisions based on the latest scientific research as well as an individual patient’s past medical history and other medical conditions.  The Joint National Committee on Prevention, Detection, Evaluation, and Treatment (JNC) has had seven publications that have been released based on scientific research about blood pressure since 1976.  The guidelines are constantly changing as we acquire new data from scientific data.

Most blood pressure medications are tolerated well, but just like any medication, there is the possibility of side effects.  I will discuss some of the possible side effects of the various classes of blood pressure medications.  If you experience side effects, allergies or just don’t like the medication prescribed, I recommend discussing this with your doctor right away rather than just stopping the medication because there might be some reason (other than the medication) that could be causing an undesired effect.  It’s also true that you might not notice an immediate drop in blood pressure right after starting some types of blood pressure medications.  It can take a few days or even weeks to achieve the full effect with certain medications.

You should know that it often takes more than one blood pressure medication to get blood pressure under control.  These medications are often used together and work in different ways to reduce blood pressure.  We might use 1, but often use 2, 3 or 4 different blood pressure medications to achieve the blood pressure goal (less than 140/90 for example).

ACE (angiotensin converting enzyme) inhibitors block a hormone in the body that causes narrowing of the blood vessels.  By allowing the blood vessels to widen, it lowers the blood pressure and improves the heart output.  This is usually the first type of medication that is prescribed for someone who has high blood pressure because it usually works so well and because there are usually not many side effects.  Some of the common ACE inhibitors are lisinopril, benazopril, enalopril, captopril and ramipril.  There are many more ACE inhibitors available that are not named here.  We also prescribe ACE inhibitors to patients who have chronic kidney disease, heart failure or diabetes.  Usually these patients also have hypertension, but not always.  If they don’t have high blood pressure, the ACE inhibitors are usually used because they protect the kidneys from damage due to elevated blood sugar.

Possible side effects:  The most common complaint of patients who cannot tolerate an ACE inhibitor is a persistent, dry, hacking cough.  About 10% of people who are prescribed an ACE inhibitor may experience a cough (that goes away after stopping the medication), and if that happens to you, we can use another similar medication – see ARB (angiotensin II receptor blocker) medications.   A very small percentage of people can have an allergic reaction to ACE inhibitors that causes swelling of the lips/mouth (angioedema).  If you develop swelling of the lips, tongue or mouth you shouldn’t take this medication and talk to your doctor right away.  We don’t see it happen very often but severe allergic reactions to any medication can be life threatening so it’s important that if you have trouble breathing after taking any medication, you call 911 (an emergency/ambulance team) instead of trying to drive to a hospital yourself.


Angiotensin II Receptor Blockers (ARBs):  These medications work similar to ACE inhibitors to reduce blood pressure but have their effect at a different site in the kidney than the ACE inhibitor.  These are newer medications than ACE inhibitors and are generally more expensive.  Since they work in a similar way to ACE inhibitors, we usually use these mostly in patients who cannot tolerate and ACE inhibitor or have chronic kidney disease.  They also work to widen the blood vessels to lower the blood pressure.  Some examples of ARBs include losartan, valsartan, and candesartan.  Not all ARBs are mentioned here.

Possible side effects:  The main difference between the ACE inhibitor and the ARB is that patients who cannot take the ACE inhibitor due to cough, can usually tolerate the ARB.  Angioedema (allergy) is also less common in ARBs.


Diuretics:  These medications lower your blood pressure by causing your kidney to produce more urine (which contains water, sodium and potassium).  You might notice that you have to get up to go to the bathroom more frequently when you take a diuretic blood pressure medicine.  Having less water/fluid in the blood vessels decrease the pressure inside the vessels (like having less volume of water running through a garden hose decreases the pressure inside of it).  There are different classes of diuretic medications to discuss:

1)      Thiazide diuretics:  Usually these medications are taken once a day.  Common examples are chlorthalidone and hydrochlorothiazide (HCTZ).

2)     Potassium-sparing diuretics:  Spironolactone, triamterene or amiloride are diuretics which do not cause as much loss of potassium in the urine as some of the other diuretics.

3)     Loop diuretics:  Lasix is an example of a stronger diuretic that lasts only 6 hours (so it has to be taken multiple times each day) but is used for patients who have high blood pressure and congestive heart failure.  We don’t use loop diuretics as often with high blood pressure because they we have to be very careful to monitor the potassium closely in patients who take loop diuretics.  This means that patients taking these medications may be asked to get blood work done fairly frequently.

Possible side effects:  Diuretics are usually very well tolerated and the main complaint that I hear people complain about is having to urinate more frequently.  I usually recommend taking a diuretic in the morning rather than the evening so that if they do have to urinate more frequently, they get most of the effect in the day when they’re awake.  We need to check kidney function and electrolytes when patients take diuretics to make sure that the sodium and potassium do not get too low.  People who have gout sometimes have more attacks if they take thiazide diuretics.


Calcium channel blockers:  These medications reduce the amount of calcium that enters the cells of the heart thereby causing the cells of the heart to relax and dilate and reduce the pressure as well as reducing the force and rate of the heart.  There are two categories of calcium channel blockers:

1)      Dihydropyridine – examples include amlodipine, nifedipine, and felodipine.  There are many others  as well.

2)     Nondihydropyridines – examples include diltiazem and verapamil

Possible side effects:  Sometimes patients who take calcium channel blockers may develop headache, dizziness, flushing, nausea or swelling of the gum tissue (gingival hyperplasia).  It the dose of medication is too strong, it can cause the heart rate to slow too much and lead to dizziness or falling.


Beta blockers:  These medications lower the blood pressure by decreasing the rate and force of the heart when it pumps blood.  Some examples of common beta blockers include metroprolol, atenolol, carvedilol and labetalol.  The last two beta blockers listed here also cause relaxation of the blood vessels (alpha blocking effect).

Possible side effects:  Beta blockers have a higher chance of causing side effects than some of the other blood pressure medications that are commonly prescribed so they are often reserved for patients who have resistant hypertension or have had a heart attack or heart failure.  We often give beta blockers to patients who have migraine headache because the medication helps to reduce the frequency of migraine we believe by affecting the nervous system/blood vessels.  People with panic disorder or anxiety may also benefit from taking beta blockers because patients often feel more relaxed while on this medicine, perhaps because of the effect on the sympathetic nervous system.

Patients who have asthma sometime get worsening symptoms from their asthma if they use beta blockers.  We are careful with the use of beta blockers in patients who have diabetes (and who sometimes get low blood sugar from their insulin) because the beta blockers can sometimes make it difficult for patients with a low blood sugar to feel symptoms of it coming on.  Beta blockers can also cause fatigue, dizziness, sleepiness, and decreased ability to exercise in some patients.

Alpha blockers:  These medications relax the blood vessel s in the body and thus allow the diameter of the vessels to widen.  Since vessels are wider, the pressure is decreased – think about how a nozzle works on a hose.  If you widen the nozzle and amount of water that is able to go through the hose, the pressure will decrease.  Some common alpha blockers are doxazosin, prazosin and terazosin.

Possible side effects:  The most common side effect of alpha blockers is dizziness, especially when standing up quickly.  We usually don’t use alpha blockers as a first medication for treating high blood pressure because of this possible side effect.  Men with an enlarged prostate and high blood pressure however may benefit from one of these medications because they can help to shrink the prostate and help increase the urine flow and decrease blood pressure.

Direct vasodilators:  We sometime prescribe medications that directly relax the blood vessels quickly, especially in patients who come into the hospital with severe hypertension.  These medications are short acting and as they wear off they can lead to an increased heart rate so we usually only use these medications in combination with a medication such as a beta blocker.  Common direct vasodilators include hydralazine or minoxidil.

Possible side effects:  headache, weakness, nausea and rapid heartbeat or possible side effects.  We also use minoxidil topically (Rogaine) for hair growth because it increases the blood flow to the hair follicles.

My recommendations:  Patients who have high blood pressure and are motivated to get their blood pressure controlled can do so but it might take some time and effort on their part.  After consulting with their primary physician and coming up with a treatment plan, I next recommend obtaining a blood pressure cuff and measure blood pressure twice a day.  The first measurement should be done first thing in the morning after getting up and before having any coffee (or other caffeinated beverages).  Write this number down and also record another blood pressure right before going to bed.  It’s important to get your blood pressure less than 130/80 consistently.

I have a tendency to value the home blood pressure records more than what we measure in the office because there is often some stress with getting to the doctor’s office on time, parking , waiting in an exam room, etc. all of which may not be a pleasant experience.  We can check your blood pressure cuff in the office and see how it compares to our cuff and ensure that it is accurate.  If your blood pressure is consistently higher than it should be, we may make changes in your medications by adding additional medications or increasing the dosage of medications that you are already taking.

Again, do not stop taking your medications without telling your doctor.  If you don’t take your medications, medical providers cannot help you with your blood pressure.  We need to know if you cannot take them and we can even work with you to help you remember to take your medications if you forget.

Tips on checking your blood pressure at home:

1)  Sit in a chair that supports your back.  Rest your arm on a table so that your upper arm is at the same level as your heart.

2)  Sit with your arm slightly bent with your palm up.  Keep your feet flat on the floor and your legs uncrossed.

3)  Use the same arm every time you check your blood pressure

4)  Make sure that you can put the blood pressure cuff directly on the skin of your upper arm.  You may need to remove any sweaters or pull up your sleeves. Be sure that your sleeves are not too tight around your arm.

5)  Wrap the blood pressure cuff snugly around your upper arm, palm facing up.  The lower edge of the cuff should be about 1 inch (2.5 cm) above the bend in your elbow.

6)  Press the on/off button on the electronic monitor.  Follow the manufacturer’s instructions for using the device.

7)  The blood pressure cuff will automatically inflate to about 180mmHg (unless the monitor decides you need a higher number).  Then the cuff will begin to delate automatically and the numbers on the screen will begin to drop.

8)  Wait at least 5 minutes before taking another blood pressure readings working properly.

9)  Look often at blood the blood pressure cuff and rubber tubing.  Make sure that they are in good condition and do not have any holes or cracks.

9)  When you purchase a blood pressure monitor, bring it to the doctor’s office to compare the reading you get with the reading that is taken in the office.  They should be close. Repeat this check yearly to make sure your machine is working properly.

This document is for informational purposes only, and should not be considered medical advice for any individual patient.  If you have questions please contact your medical provider.


I hope that you have found this information useful.  Wishing you the best of health,

Scott Rennie, DO

Blog: https://doctorrennie.wordpress.com

Legal Concerns in the Wilderness

shutterstock_133594121Sadly, due to our litigious world, our well-meaning care giver has concerns of legal liability even in the wilderness.   I enjoy going out into the wilderness and on some occasions I’ve come across an accident victim or other medical emergency in the back country.  It is my instinct to provide medical care for someone who needs it, and according to the World Medical Association’s International Code of Medical Ethics, “…a physician shall give emergency care as a humanitarian duty…”

I will attempt to summarize information about legal concerns in the wilderness as given by a recent class in Advanced Wilderness Life Support and the information comes from their student book.  I am not an attorney and the information presented here is for informational purposes only.  I do not gain anything from presenting this information, but I think it’s important for all of us to understand legal concerns when providing medical care in the wilderness.   If you have a specific situation or concerns, I recommend that you speak to an attorney to get your questions answered.

Again just to clarify, I am not the originator of this material.  The information here comes from a recent class in Advanced Wilderness Life Support and from their instruction manual.  You can contact the company who teaches these classes (Wilderness Medical Society) at the address shown here:  http://www.wms.org  I highly recommend taking their AWLS (Advanced Wilderness Life Support) class.

Good Samaritan Laws:  The purpose is to provide liability protection to those with the ability to help in an emergency to remove the deterrent of litigation as long as the caregiver is not grossly negligent.  There are differences in each State in how the law is interpreted.  Actual fines may be imposed in some states, in Quebec and in Europe if there is a failure to render aid.  That obligation might be satisfied by immediately reporting the situation to the proper authorities who can provide help and aid to the victim.

For a medical provider to be protected under the Good Samaritan Doctrine, the following five guidelines must be met:

1)   The person rendering emergency care must not have caused the emergency, either in whole or in part.

2)   The person rendering emergency care must act in “good faith.”

3)   The emergency care must be provided gratuitously, without any compensation.

4)   The provider must not commit gross negligence when rendering emergency care.  It would be difficult to list all possible acts or omissions that might constitute gross negligence.  Once initiating emergency aid in the back country and then either terminating treatment or transferring care to an inadequately trained person before the patient is stabilized to a medical facility can be considered abandonment and that can be seen as gross negligence.

5)   The person rendering emergency care must not have preexisting duty to care for the patient.  A guide for example, would have a preexisting duty to render emergency care to a customer if the customer had contracted with the guide to be taken on a hike and the guide had agreed to provide care to the customer in case of injury when hiking.

If any one of the give conditions above is not satisfied, then the Good Samaritan law, with all it’s protection, will not apply.

It would seem that the most frequent violation that would cause the Good Samaritan Law to be nullified arises from the presence of a preexisting duty on the part of the care giver to provide aid to the patient because of contract law.

Contract Law:  It would behoove a medical provider on an expedition, to avoid being involved in a contract that in any way gives the belief or guarantees that safety and health are ensured during the trip.  A contract is an agreement or promise between two or more parties for performing or not performing certain specified acts in exchange for adequate consideration.  Contracts can be either “express” or “implied-in-fact.”  An express contract usually states explicitly in words, either written or oral leaving little or no doubt as to the existence and terms.  An implied contract is created by conduct or circumstances that “imply-in-fact” a contract exists.

A brochure from a summer camp, expedition company or an adventure guide might sometimes expressly state that they have a trained person available to provide medical care to customers in emergencies arising during the adventure activity.  This could also be implied during an oral presentation or in a brochure.  Good Samaritan law will not be of protection from liability if a court finds that the complaining customer took part in the expedition in part because the company contractually agreed to provide medical aid during an emergency.

Tort Law:  Torts are legally defined as civil (non-criminal) wrongs that might result in harm or injury and, thereby, constitute the basis for a claim (or law suit) by the harmed or injured party against the person who allegedly committed the tort.

Three categories of torts:

1)   An intentional tort (where one person intentionally harms or injures another).

2)   A strict liability tort (making and selling an obviously defective product).

3)   A negligent tort (a careless an unintentional act, such as an automobile accident, which harms or injures another person or another person’s property.)

Most often law suits claim that the tort of “negligence” occurred.  In order to prove that a person who provided emergency medical care in the back country committed the tort of negligence, the person who was harmed must prove the four elements of a negligence claim:

Four elements of a Negligence Claim:

1)   Duty to Provide Care at the Standard of Care:  If the provider gave care that met the prevailing standard in the medical profession, the healthcare provider will likely not have been seen as negligent.  The question of what the prevailing standards are can sometimes be in question.  That standard is often not yet well established in law.  When in doubt, courts will rely upon the traditional legal definition of the standard, which is the “behavior of a reasonably prudent person in the same or similar circumstances.”  Some factors the court may look to in determining the applicable standard of care are:

  1. The defendant’s education
  2. The defendant’s training
  3. Government or organization medical protocols that apply to the particular situation
  4. Industry practice
  5. Private business protocols that might apply

Generally, if there is a duty to provide care that meets a certain standard, an informed consent is obtained from the patient before the treatment is given.  In an emergency however, a health care provider might rely on “implied consent” where most would reasonably assume that the patient would have agreed to the care offered under the emergency circumstances if they were able to do so.

2)   Failure to Perform the Duty:  It is very important to remain well informed of the prevailing medical standards and protocols and be well trained in wilderness medicine to ensure that any care provided meets the applicable standards.  The plaintiff must prove that the care provider did not perform the duty of providing aid consistent with the specified standard of care.  Usually the plaintiff asserts that the provider failed to act at all (an omission) when the provider had a pre-existing duty to provide care.  The plaintiff may also assert that the provider provided care that did not meet the prevailing medical standard or did not perform as would a reasonable person with the provider’s background, education and training.  If the provider prematurely terminates care or transfers care to a less qualified provider before the patient has been stabilized, this can be considered abandonment and constitute negligence.

3)   Loss of injury:  The plaintiff must prove that they sustained a loss or injury which can include damage to property, medical expenses, fright, emotional trauma, personal injury, pain and suffering, and loss of life.

4)   Causation:  The plaintiff must prove that the loss or injury was caused or contributed to by the provider’s failure to perform the duty of providing aid meeting the specified standard of care.

Defense in a tort law claim:  Experience teaches that a record including dates, times, patient history, a description of the scene, and a complete and accurate record can help defeat a plaintiff’s claims.  The care provider can defeat the plaintiff’s claim if the plaintiff failed to carry the burden of proof on one or more of these four elements of the negligence claim.

Jurisdiction:  Laws can widely vary from country to country and even state to state.  Knowing ahead of time, what the jurisdiction is will allow for maximum protection from litigation and optimal conduct.

Malpractice Insurance:  It makes good sense to check with malpractice carriers before undertaking a trip to find out if they will be covered when rendering support during expeditions in various jurisdictions.

References:  Advanced Wilderness Life Support Student Handbook

This document is for informational purposes only, and should not be considered medical advice for any individual patient.  If you have questions please contact your medical provider or your attorney.


I hope that you have found this information useful.  Wishing you the best of health,

Scott Rennie, DO

Blog: https://doctorrennie.wordpress.com

Lightning Injuries and Prevention

shutterstock_15532345I’ve met a few people who have been struck by lightning and lived to tell about it, and I thought I’d pass along some information about lightning injuries and how to prevent them.  Much of this information comes a recent class in Advanced Wilderness Life Support (AWLS)

Interesting facts about lighting:

•  Lightning strikes are the second leading environmental cause of death (behind flash floods) in the United States, with an average of 50-300 deaths per year.

•  There are 3-5x as many people who are struck by lightning and survive than die.

•  Nationally, there are 20 million cloud-to-ground flashes detected annually.  In some summer afternoons, more than 50,000 flashes per hour are detected.

•  The most common months of injury are June, July and August, although lightning strikes may occur during any time of year (even in snowstorms).

•  The most common time of day for deaths due to lightning strikes is in the afternoon between 3pm and 6pm local time and this is because of the sun heating the ground which causes vertical cumulus clouds to form that may be tall enough to produce lightning.

•  Florida is the worst state for lightning deaths with nearly 2x as many deaths than the next state.

•  The most dangerous times for a severe lightning strike are before the storm appears and after it has passed.

•  Lightning may travel nearly horizontally as far as 10 miles in front of a thunderstorm and seem to occur out of a “clear blue sky,” or at least when it is sunny.

•  Lightning does commonly strike twice in the same place.

•  A lightning bolt is a unidirectional massive current impulse carrying up to 30 million volts.

•  A lighting bolt is about 6-10cm in diameter, but the ionized sheath is much broader (up to 20cm).  The temperature of the sheath is usually around 8,000 degrees centigrade.

•  There is no need to be concerned about getting shocked or injured by rescuing a person who has been struck by lightning because lighting does not leave a residual charge on a victim.

•  Contrary to popular myth and what is seen in cartoons, deep burns are unusual after lightning injury.  At the most, some minor second-degree burns may occur from superheated metal objects.

Mechanisms of injury:  People can be injured by lightning in several ways:

1)   Direct strike:  a person is hit directly by a bolt of lightning and this happens most commonly with people who are caught in the open and unable to find cover.  This is the deadliest type of strike.

2)   Side splash:  lightning directly strikes another object such as a tree or building, but the current flow, which seeks the path of least resistance, jumps from its original pathway onto the victim.  This is the most common cause of lighting injury. Side splashes may also splash indoors from metal objects such as plumbing or telephones and may even occur from person to person when several people are standing close together.

3)   Contact exposure:  occurs when a person is holding onto or touching an object that is either directly hit or splashed by lightning.  The current passes through the object onto the victim.

4)   Ground current or step voltage:  lightning strikes the ground or a nearby object and the current spreads through the ground.  If a person has one foot closer to the strike than the other foot, an electrical potential difference between the two feet may occur and the current may pass up one leg and down the other leg.  This is a common mechanism for several people being injured at the same time.

5)    Blunt trauma:  injury due to the impact of the concussive force of the strike itself or from being thrown due to the extreme nature of the muscular contraction from the electrical charge.

How lightning affects the body:  injuries occur from a “short circuiting” of several of the body’s electrical systems as well as the more direct trauma and indirect trauma due to the muscular contraction and being thrown.  The most common cause of death in a lighting strike victim is cardiopulmonary arrest.

Treatment:  I think it’s important for everyone to be trained in CPR.  In lightning victims, we usually perform reverse triage and initiate CPR on those patients who are pulseless and apneic (not breathing) before caring for those who have spontaneous signs of life.  This is because those with no spontaneous breathing or heartbeat may recover and will require assisted breathing until their respiratory drive returns.  Assisted breathing for these patients may prevent a secondary cardiac arrest due to low oxygen intake.  If a victim does not regain a pulse within 20-30 minutes we usually then discontinue the resuscitation.  The patient will need evacuation to the nearest medical facility even if the individual does not have any overt evidence of damage.  There is a high likelihood of some sort of injury that is not served best by staying in the outdoors.  Splinting fracture and spinal precautions is necessary.

Avoiding lightning injuries:

1)   30-30 Rule:  The first “30” is when the time between seeing the lightning and hearing the thunder is 30 seconds or less, then people are in danger and should be seeking appropriate cover.  The second “30”:  outdoor activities should not be resumed until 30 minutes after the last lightning is seen or last thunder is heard.

2)   Seek shelter in a substantial building or in an all metal vehicle:  small shelters such as golf, bus and rain shelters may increase a person’s risk of being struck due to side splash as the lightning flows over the building.  All metal vehicles are safe because the metal will diffuse the current around the occupants to the ground.  A convertible is not a safe alternative.  It is a myth that rubber tires provide insulation.

3)   If you are caught in a storm outside without a safe building or vehicle:  Stay away from metal objects and those items that are taller than you.

4)   Avoid areas near power lines, pipelines, ski lifts, and other large steel objects.

5)   Do not stand near or under tall isolated trees, hilltops, or at a lookout or other exposed area.

6)   In a forest, seek a low area under a growth of saplings or small trees.  Seeking a clearing free of trees makes a person the tallest object in the clearing.

7)   If you are completely in the open, stay far away from single trees to avoid lightning splashes and ground current.

8)   If you are on the water, seek the shore and avoid being the tallest object near a large body of water.

9)   If indoors, avoid open doors, windows, fireplaces and metal objects such as sinks and plugged in electrical appliances.  Do not talk on the telephone, as the telephone lines are not usually grounded like electrical wires.

References:  Advanced Wilderness Life Support Handbook

This document is for informational purposes only, and should not be considered medical advice for any individual patient.  If you have questions please contact your medical provider.


I hope that you have found this information useful.  Wishing you the best of health,

Scott Rennie, DO

Blog: https://doctorrennie.wordpress.com

Avoid heat related illness – Dr. Rennie KING 5 News

To learn about how to avoid heat related illness, check out my video on KING 5 News – Seattle


Scott Rennie, DO is an urgent care physician practicing in the greater Seattle area. His focus is providing expert medical care with personalized service in the realm of urgent care, wilderness medicine, primary prevention, and whole-body wellness.