63.2 Monitoring a patient with a head injury

The best indicator of the function of a patient’s brain is his level of consciousness. If this is deteriorating he needs burr holes. Deterioration is a trend (for the worse), and is much more important than his status which is his state of consciousness at any one time. The idea that ’trend is more important than status’ is the key to monitoring these patients. The only reliable way to monitor deterioration is to use a head injury chart, like that in Fig. 63-4. There is a blank full sized version of this on one of the end pages of the book. Have some photocopies made. All patients with a head injury need one, because even a mildly injured patient can deteriorate rapidly. When you assess consciousness, don’t rely on subjective statements like ’fully conscious’, or ’partly conscious’. Instead, record objectively what a patient can do. Use, and teach the nurses to use, expressions which do not need description, such as ’alert but confused’, or ’not speaking but obeys commands’. Show them how to fill in a head injury chart. If it is too complicated, teach them to fill in part of it. Encourage them to form their own base lines, so that they can say at any time if they think a patient is getting better, or worse.

Figure 63.4: CHARTS FOR A SUBDURAL AND EXTRADURAL HAEMATOMA. The changes are similar. The main,difference is that the changes in an extradural haematoma develop faster. There is a blank copy of this chart on one of the endpapers so that you can photocopy it. Kindly contributed by Gerishom Sande.

Date the chart from the moment of a patient’s injury, and enquire most carefully about his level of consciousness before admission. To begin with, make hourly, and later 2 hourly observations of his verbal responses, his motor activity, and his pupils. Record his systolic blood pressure and his pulse. Warn the nurses to expect rapid changes in the things you ask them to watch, and to report them urgently. For example, a blood pressure reading, which is obviously different from the previous one half an hour before, may be very important, but check it again before acting on it. Make sure they know how to examine a patient’s pupils, and test their reactions to light. The easiest test for pain is to pinch him firmly with your finger nail. As with all charts, nobody is going to fill them in carefully, unless they understand them and see you look at them and act on them.

Figure 63.5: LOSS OF CONSCIOUSNESS AFTER A HEAD INJURY. All patients, except F, were concussed to begin with. Patient A, was concussed, lost consciousness momentarily, and then became normal again (common). Patient B’s brain was seriously contused, he became deeply unconscious and remained so (common). Patient C was concussed and contused, and became deeply unconscious, after which consciousness steadily improved (common). None of these patients is deteriorating, so they don’t need burr holes.The patients who have cerebral compression and need decompression are D, E, and F, all of whom are deteriorating. Patient D was concussed then had a lucid interval before becoming unconscious again (rare but important). Patient E was concussed, his consciousness improved and then deteriorated again (not so rare). Patient F did not lose consciousness at the time of the injury, but progressively lost it afterwards (rare). Kindly contributed by Peter Bewes.

Assume that any deterioration of consciousness is caused by rising intracranial pressure, and needs burr holes, until you have proved otherwise. Here are some of the other causes.

Some major thoracic or abdominal injury causing severe blood loss, or impairing respiration and raising the carbon dioxide tension in the patient’s blood. When this happens operate without delay, whatever his level of consciousness.

A major generalized or focal convulsion, especially in a child, can impair consciousness for several hours. Don’t accept this as the cause, unless someone saw it happening. Prophylactic phenobarbitone should prevent it.

Fat embolism can cause rapid deterioration in consciousness, but usually only if the patient has long bone fractures of his legs, or severe soft tissue injuries (78.6). His consciousness can deteriorate before petechial haemorrhages appear. His pupils remain equal, and the characteristic pulse and blood pressure changes of cerebral compression are not seen.