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Medical Information

When you want, or need, to know more than the superficial, such as when you are

where there is no access to a physician.

Prototypically: Medicine at Sea


This medical information is provided for education purposes only. I am making no attempt to practice medicine over the internet. This is being written to give some basic knowledge for those that are physically isolated from access to professional medical care, such as sailors at sea. This is to help in deciding whether an emergent medical condition exists, how to initially deal with it, and whether evacuation is needed. It is by no means exhaustive or meant to replace personal medical attention. Please do not contact me regarding your personal condition. Over the years I have received many emails from people asking for help with their personal chest pain, or whatever. Sometimes they write during acute pain. This is ridiculous. You can't practice medicine over the internet. If I find their email, after it has been filtered by my spam filter, it may be days or weeks later. My response, if any, will be to contact their regular provider. Even a bad doctor in person is better than an email. Please use this information in the spirit in which it is intended.

Sincerely, Mark R. Anderson, M.D.

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Head (and Neck) Injuries

Expanded March 21, 2010


(and Neck) Injuries



Is it serious?

This is what we're always trying to determine.

Just a bump - Scalp hematoma

Not an indicator of seriousness. Ice bag it.

Is the neck injured?

If there’s no paralysis or numbness, and the sober pt. is willing to move it - OK

Delayed pain and stiffness = Spasm usually.

Worrisome is immediate severe pain, w/ or w/out nerve symptoms and patient won’t move it.

Often nerve injury isn’t immediately apparent.

Traumatic Brain Injury

Several types: Types can occur in combination.


Temporary traumatic brain dysfunction without anatomical injury. Generally knocked out, (or severely dazed), headache, confusion.

Improves quickly with time. Though minor symptoms may last weeks.

Cerebral contusion:

The brain itself is bruised. Generally has severe persistent headache and vomiting. May be confused or have local signs of damaged brain function, e.g. weakness, clumsiness, numbness, visual change. Not much can be done except wait and maybe give high dose steroid drugs to reduce swelling. Treat complications, e.g. seizures. Tends to improve with time but may have permanent loss of function.

Subdural hematoma.

The brain itself is not damaged but a clot develops over the surface of the brain from venous bleeding. The clot then compresses the brain causing increasing symptoms. Progression can be over hours to weeks. Prognosis is generally good if the clot is extracted as the brain itself is not damaged. If there is severe swelling it tries to squeeze the brain down through the hole in the base of the skull, thereby compressing the brain stem. This leads to a terminal deterioration. The victim will likely already be comatose (i.e. can't be awakened), one pupil (generally on the side of the bleeding) will become 'blown' (very large and unreactive to light), the blood pressure will go up and the pulse will go down. Death follows unless emergency life saving surgery. A stop gap temporazing measure is the drill a hole through the skull above the ear on the side of the blown pupil that may allow the clot to come out and relieve the pressure. This was even done in ancient times (e.g. the Incas) and people did survive.

Epidural hematoma

Everything I've said about subdural hematoma applies here except: The caused is arterial bleeding, often because of a skull fracture that cuts an artery crossing inside the skull at the temple. Therefore everything happens faster. There may be a so called "lucid interval". The victim has the head injury and is likely knocked out, but then awakens and seems fine. Minutes to hours later (i.e. faster than with a subdural), the deterioration begins.

Clinical key is that the patient is worsening - You need help to clarify what the problem is.

Before the ready availability of CT scanners, i.e. in the first 10 years of my medical career, the common practice was to just do close observation (either at home or in the hospital) to watch for deterioration. If you are isolated, e.g. at sea, you are back in that mode. However you should try to get in contact w/ evacuation help early in case you need it.


Check the victim every 15 minutes for the 1st hour, then every hour for 4 hours, then every 3-4 hours after that. Generally if something bad doesn't happen in the 1st 24 hrs it won't, but there are exceptions to that rule. (The chronic subdural can develop over weeks).

Observation means:

Are they awake, or can they easily be awakened to full coherence?

Is there a worsening headache? Is there repetitive vomiting? It's not unusual, especially in kids, to vomit once. Twice is more ominous.

Is their grip strength equal in both hands?

Are the pupils equal and size and both react by constricting to a bright light, (e.g. a flash light shown into the eye)? Be aware that about 10% of people always have unequal pupils, so we're looking for a significant change from baseline. Hence it pays to check the eyes right after the injury. Also, if there is a direct blow to the eye the pupil may be stunned, dilated and unreactive. If the patient has abnormal pupils, but otherwise seems OK, the pupil change is probably not due to brain injury.

Danger signs:

Vomiting, Increasing confusion, Unequal grips, Clumsy, Lethargy, Coma Late sign is unequal pupils.

If the patient is DYING, no help can come, and one pupil is very large and unreactive to light (i.e. doesn't constrict to bright light):

Consider drilling a hole thru the skull above the ear to let the blood clot

and pressure out. Drill on the side of the blown pupil.

Head Injury and Concussion syndrome:

Head injuries are common and fortunately most are minor. On the other hand it is not always possible to tell at the initial evaluation whether there are, or will be, any problems.

Concussion is a traumatic disturbance of brain function without visible damage. This usually means being knocked out briefly but then seemingly fine. If the patient remembers the impact, there was no loss of consciousness, but there could still be a concussion if there are other symptoms. The patient does not need emergent CT scanning unless he/she develops a severe persistent headache again or develops vomiting, new symptoms or general deterioration. The patient should stay with a responsible observer for at least the 1st 24 hrs. if the injury is considered to be more than trivial. The observer is responsible for awakening the patient during the night to confirm his/her condition in more serious injuries. Some concussions are followed by persistent headaches or other symptoms such as difficulty with concentration for some time. Generally you should expect to be symptom-free within a couple days and able to return to regular activity in a week. Vigorous activity, e.g. sports, should be avoided for a week, or longer if so advised. "Second impact syndrome" is the possibility of much more severe problems if another head injury occurs within a few days of the first.

Initially headache should be treated with ice bag, and Tylenol. Try to avoid stronger pain pills because they can cause drowsiness and confuse the picture.

Seek emergent medical evaluation if DANGER SIGNS develop: Severe persistent headache again, repetitive vomiting, new symptoms or a general deterioration such as confusion or drowsiness.

A head CT will not show a concussion because there is no visible damage. A CT is used to rule out more serious injuries such as brain bruising, bleeding into the brain itself, or bleeding over the surface of the brain compressing it.



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