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Acute confusion secondary to pneumocephalus in an elderly patient

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Acute confusion secondary to pneumocephalus in an elderly patient Powered By Docstoc
					Age and Ageing 2000; 29: 365–367                                                            2000, British Geriatrics Society


CASE REPORT

Acute confusion secondary to
pneumocephalus in an elderly patient
YUN P. CHAN, CHI Y. YAU, ROGER R. LEWIS, MARK T. KINIRONS
Department of Geriatrics and General Medicine, Guy’s and St Thomas’ NHS Trust, Ground Floor, Thomas Guy House,
Guy’s Hospital, London SE1 9RT, UK

Address correspondence to: M. T. Kinirons. Fax: (+44) 20 7 955 4465. Email: mark.kinirons@gsst.sthames.nhs.uk


Abstract
Presentation: an 83-year-old man was admitted to hospital with acute confusion 3 days after a direct flight from
Australia.
Outcome: computed tomography (CT) brain scan and magnetic resonance imaging head scan revealed the cause
to be pneumocephalus, apparently the result of barotrauma caused by Valsalva manoeuvres when he attempted to
unblock his nose during the flight. After 5 days of nursing in the vertical position the patient’s Abbreviated Mental
Score returned to normal. A CT brain scan 6 weeks later showed complete resolution of the pneumocephalus.

Keywords: air travel, meningitis, pneumocephalus, Valsalva manoeuvre




Introduction                                                       His admission full blood count, erythrocyte sedi-
                                                               mentation rate, urea and electrolytes, liver and thyroid
Pneumocephalus is a rarely reported cause of acute             function tests, calcium, vitamin B12, blood sugar,
confusion [1, 2]. We believe this is the first report of an     serum folate, VDRL and chest X-ray were normal, as
elderly patient developing acute confusion due to              were an MSU, arterial blood gases and blood cultures.
pneumocephalus resulting from barotrauma during an                 A computed tomography (CT) brain scan showed
aeroplane flight.                                               extensive intraventricular air in the lateral ventricles
                                                               (Figure 1) and there were also multiple lucent areas
Case report                                                    within the cranial vault, particularly in the sphenoid
                                                               wing and posterior wall of the right frontal sinus.
An 83-year-old man was admitted to hospital with                   A magnetic resonance imaging (MRI) head scan
acute confusion. Three days previously he had                  confirmed the pneumocephalus and lucent areas, as
returned by direct flight from a 4-week holiday in              well as showing a trace of extradural blood in the right
Australia. When on holiday, he had had no illnesses or         sphenoid region, which was consistent with trauma.
accidents. He had a history of recurrent left nasal            No connections were seen between the sinuses and
obstruction and chronic sinusitis following an injury          intracranial space.
in his youth.                                                      In view of the lucent areas on the brain scans, a
    Soon after the aeroplane took off, he developed a          myeloma screen and bone scan were performed; both
blocked nose which he tried to clear vigorously by             were normal.
repeatedly blowing his nose. When the plane landed,                There was no evidence of infection and a lumbar
his nasal obstruction had cleared. He travelled home by        puncture was not undertaken. Prophylactic amoxycil-
underground train and bus without difficulty, but over          lin was prescribed. A fibreoptic nasendoscopy did not
the next 2 days his daughter noticed he had become             show a communication between the sinuses and
increasingly confused.                                         intracranial space.
    On examination he was disorientated, with an                   The patient was nursed in the vertical position and
Abbreviated Mental Test score of 4 out of 10. No other         improved over the next 5 days, his Abbreviated Mental
abnormality was noted, and subsequent examinations             Score returning to normal. He remained well when
showed no intracranial succussion splash.                      seen in the outpatient clinic 6 weeks later and a repeat


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Y. P. Chan et al.

                                                             by Markham [1] and to our knowledge has been the
                                                             presenting complaint for pneumocephalus in only one
                                                             previous report [2]. The pathognomonic physical sign of
                                                             pneumocephalus is an intracranial succussion splash,
                                                             but this is present in only 7% of patients [1].
                                                                 Pneumocephalus is usually benign, absorption of
                                                             the air occurring in 85% of patients in the first week
                                                             [4]. This is likely to have occurred in our patient, since
                                                             his symptoms improved within a few days. Most of the
                                                             remaining 15% are at higher risk of infection because a
                                                             dural tear with cerebro-spinal fluid (CSF) rhinorrhoea
                                                             figures prominently in this group. A further complica-
                                                             tion is tension pneumocephalus, which requires
                                                             surgical drainage of the air [6]. Particular care is
                                                             needed if lumbar puncture is considered necessary
                                                             when there are features of meningitis.
                                                                 The basic management includes bed rest in an
                                                             upright position, avoidance of the Valsalva manoeuvre
                                                             and analgesia. The need for prophylactic antibiotic
                                                             therapy is uncertain, but is recommended when
                                                             pneumocephalus is secondary to trauma [1].
                                                                 The condition can be shown by plain skull X-rays
                                                             with as little as 2 ml of air in the head, while a CT brain
                                                             scan can demonstrate as little as 0.55 ml [6]. MRI head
                                                             scans are being used increasingly, as they are more
                                                             likely to show the site of any CSF fistula.
Figure 1. Computed tomography brain scan showing                 Air in the intracranial space is thought to exert a ‘ball-
extensive intraventricular air in the lateral ventricles.    valve’ effect in that increased air pressure, caused for
                                                             example by the Valsalva manoeuvre, forces air into the
                                                             skull through a dural defect, which then closes when the
CT brain scan showed complete resolution of the
                                                             intracranial pressure equals the external pressure.
pneumocephalus.
                                                                 In the patient presented, the CT and MRI head scans
                                                             showed bony lucencies in the cranium, although these
Discussion                                                   are not visible on the CT photograph. These were
                                                             consistent with chronic sinusitis, thought to be the
Air within the cranial vault usually implies a commu-        likely route through which air gained access into
nication with the atmosphere or a paranasal sinus,           the intracranial space, through a presumed defect in
although pneumocephalus can be secondary to                  the arachnoid mater. In fractures of the middle fossa,
meningitis from gas-forming organisms [3–5]. Intracra-       air enters the basal cisterns and during head movement
nial air producing a mass effect is known as tension         tracks into the ventricular system via the foramina of
pneumocephalus [6].                                          Luschka and Magendie [1].
    The cause of pneumocephalus in over 70% of                   We believe that during the flight the patient
patients is cranio-facial trauma [1]. Other causes include   developed the pneumocephalus as a result of baro-
tumours, nasogastric tube insertion, bag-mask ventila-       trauma caused by Valsalva manoeuvres when he
tion, nasotracheal intubation, use of continuous positive    attempted to unblock his nose. This may also have
airways pressure in patients with head and facial            caused the extradural blood shown on the MRI head
injuries, transphenoidal surgery [7], insertion of a         scan. The pneumocephalus is likely to have occurred
shunt [8], epidural and spinal anaesthesia, lumbar           towards the end of the flight. Had it developed soon
puncture, nitrous oxide anaesthesia and chronic otitis       after take-off, he may have become symptomatic during
media [1, 6, 9]. The three previous reports of               the flight as the air would have expanded with
barotrauma causing pneumocephalus, which were in             increasing altitude and decreased atmospheric pressure.
young adults, occurred in a pilot while flying and in
two divers during rapid ascent [6, 9, 10].
    The clinical presentation usually varies depending on    Key points
the underlying cause but includes headaches, seizures,       • Pneumocephalus should be considered as a possi-
weakness, double vision, cerebrospinal fluid rhinor-            ble cause of acute confusion, particularly when
rhoea, meningism and a frontal lobe syndrome [1, 11].          there is a history of ear, nose and throat problems,
Confusion was not a problem in 295 patients reviewed           barotrauma or head injury.


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                                                                         Acute confusion secondary to pneumocephalus

• Diagnosis is by computed tomography brain scan                          Clostridium perfringens meningitis: CT findings. AJNR 1989; 10:
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  vertical position.                                                      JAMA 1986; 22: 3154–3156.
                                                                          7. Haran RP, Chandy MJ. Symptomatic pneumocephalus after
                                                                          transsphernoidal surgery. Surg Neurol 1997; 48: 575–8.
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