Neurology
Matthew J Harris
Outline
Station 5.1: Meningitis
You are the junior doctor working in the emergency department when a 22-year-old student, Simon Peters (01/07/92), is brought in by ambulance with a headache, vomiting and neck stiffness. He looks unwell and is shielding his eyes from the light. The ambulance crew report that he seems confused and his temperature is elevated at 38.5°C. Please assess him and instigate appropriate management.
Initial Assessment
Airway
Assess patency of the airway. Is there any stridor or noisy breathing? Is there any vomit that could be obstructing the airway? Is the patient conscious enough to maintain a safe airway?
‘The airway is patent, with no obstruction. The patient is maintaining a safe airway.’
No additional airway support is required.
Breathing
Assess respiratory rate, oxygen saturations and accessory muscle use. Auscultate for air entry, and additional sounds of wheeze or crepitations
‘The respiratory rate is 22/min, oxygen saturations are 99%. There are no signs of respiratory distress. The lung fields are clear.’
The oxygen saturations are normal and therefore supplementary oxygen is not required. Oxygen therapy should be considered in all patients with sepsis. The respiratory rate is mildly raised, this is likely to be due to the systemic inflammatory response. Respiratory rate is a sensitive marker of when a patient is unwell and is often one of the first vital signs to become abnormal.
Circulation
Assess circulatory status by measuring pulse, blood pressure and capillary refill time. Is the pulse bounding (seen early in sepsis) or weak (associated with hypotension)? Are the peripheries warm (vasodilatation secondary to sepsis) or cold (is the patient peripherally shut down?)
The patient has been vomiting and it is therefore particularly important to assess fluid status. As well as BP and pulse, also examine skin turgor, mucous membranes and look for sunken eyes. None of these signs are particularly specific on their own, so an overall assessment should be made
Perform a cardiovascular examination. Assess the JVP and central pulse. Auscultate for heart sounds and any additional murmurs. Examine for evidence of peripheral oedema
‘The HR is 110 bpm, BP 125/60 mmHg, CRT is 1 second peripherally. The pulse is bounding and the peripheries are warm. Mucous membranes are dry but skin turgor is normal. On cardiovascular examination the JVP is not visible. Heart sounds are normal with no added murmurs. There is no evidence of peripheral oedema.’
The patient is maintaining an adequate blood pressure but is tachycardic and vasodilated. There are also some signs of dehydration which are likely to be secondary to vomiting
Obtain IV access, take bloods and start intravenous maintenance fluids at 125 mL/h (see initial management)
Consider the need to insert a urinary catheter to measure urine output hourly and start a fluid balance chart. Urinary catheterization should be performed in all patients with severe sepsis.
Disability
Assess the patient’s conscious level using the Glasgow Coma Scale (GCS). Ask the nursing staff to start the patient on neurological observations. Check pupil sizes and reactions. Check bedside glucose levels
‘The patient is rousable to voice and confused with a GCS of 13 (E 3, V 4, M 6). The pupils are equal and reactive to light and the blood sugar is 4.5 mmol/L.’
A full neurological examination is required to assess for any focal neurological deficit; however, initial antibiotic treatment should not be delayed while a lengthy examination is performed
Examine the cranial nerves (including fundoscopy), upper and lower limbs. If there is any focal neurological deficit this could suggest raised intracranial pressure which would be a contraindication to lumbar puncture. If there is a pressure difference between the supratentorial and infratentorial compartments, lumbar puncture may increase this pressure difference and cause brain herniation. In such cases, lumbar puncture should not be performed and antibiotics given immediately. Other signs that could suggest raised intracranial pressure include a reduced or fluctuating GCS and papilloedema
In a case of meningitis with signs of raised intracranial pressure, the nearest neurosurgical centre should be contacted and the patient should be cared for on an intensive care unit
‘Full neurological examination is limited due to patient confusion; however, there do not appear to be any focal neurological signs. Specifically, there is no evidence of papilloedema on fundoscopy; power, reflexes and tone are normal in all four limbs and there is no facial asymmetry or obvious cranial nerve deficit.’
Exposure
Expose the patient and in particular look for any evidence of rash. The presence of a non-blanching petechial rash indicates septicaemia and the patient should be reviewed by critical care for intensive care admission
Measure the temperature. Examine for neck stiffness and assess Kernig’s sign (flex the patient’s hip and when the knee is extended, there is pain and resistance). Palpate for any lymphadenopathy and examine the abdomen to exclude any pathology
‘The temperature is elevated at 38.1°C, there is no obvious rash. There is neck stiffness and Kernig’s sign is positive.’
Initial Investigations
Bloods: FBC, U&Es, LFTs, glucose, CRP, clotting, meningococcal and viral PCR. Look for evidence of infection and check platelet count and clotting before performing lumbar puncture. In severe meningitis, disseminated intravascular coagulation can occur causing deranged clotting and low platelets, both of which would be a contraindication to lumbar puncture. Send a meningococcal PCR (this is important for public health)
Blood cultures: Ensure aseptic technique when taking blood and that at least 10 mL of blood is collected in each blood culture bottle to give the most chance of culturing an organism
Venous blood gas: This is useful to assess the patient’s acid–base status and their lactate. A raised lactate may suggest reduced tissue perfusion which is a poor prognostic sign and an indicator of severe sepsis. Note that partial pressure of oxygen is difficult to assess on a venous blood gas, and if there is a significant concern about this, an arterial blood gas should be performed
CT head: If CT scanning is readily available and will not lead to significant delays, a CT head should be performed prior to lumbar puncture in all cases. If CT scanning is not readily available, lumbar puncture can be performed if deemed safe by a neurologist (i.e. none of the contraindications described below). If a neurologist is not available then the EFNS guidelines [2] state antibiotics should be given while awaiting imaging. The CT protocol may vary in individual hospitals
Lumbar puncture: This is the key investigation in this case which will give the most diagnostic information. However, as already described there are a number of contraindications to performing a lumbar puncture–these are: reduced or fluctuating GCS, raised intracranial pressure, suspected intracranial mass, focal neurology, septicaemia, shock, respiratory failure, trauma and middle ear pathology. If there are no contraindications, proceed as described below:
Ensure that the platelets, clotting and CT scan are normal prior to lumbar puncture and consent the patient if they are able to
Measure the opening pressure using a manometer (normal<25 cmH2O)
Send the 1st and 3rd bottles for microscopy, culture and sensitivity
Send the 2nd bottle for biochemistry (protein and glucose) and send a paired serum glucose
Send the 4th bottle for meningococcal PCR and viral PCR (if encephalitis suspected)
If subarachnoid haemorrhage is suspected, a CT head should be performed prior to lumbar puncture. If this is clear, a 5th bottle can be sent for xanthochromia (taken at least 12 hours following the time of the suspected subarachnoid haemorrhage)
Send the samples urgently to the lab and contact the microbiologist on call to alert them of the patient (urgent microscopy will be required) and for advice on antibiotic choice
EEG and MRI head: If there is concern of encephalitis then EEG and MRI can be useful, both usually illustrating changes in the fronto-temporal lobes
Throat swab: Send throat swabs for bacterial and viral culture
Septic screen: In view of the temperature, a chest X-ray and mid-stream urine analysis should be performed to exclude any evidence of pneumonia or urinary tract infection. In view of the vomiting, aspiration pneumonia should also be suspected; however, clinical examination in this case does not suggest any evidence of pneumonia
‘Blood testing reveals WCC 25×109/L, neutrophils 21×109/L, CRP 80 mg/L. Platelets and clotting are normal. Venous gas shows normal acid–base balance and a lactate of 1.5 mmol/L. CXR is clear, blood cultures and MSU are sent. A CT head is arranged prior to lumbar puncture.’
Table 5.1
Parameter | Value | Normal range (Units) |
WCC | 25×109/L | 4–11 (×109/L) |
Neutrophil | 21×109/L | 2–7.5 (×109/L) |
Lymphocyte | 2×109/L | 1.4–4 (×109/L) |
Platelet | 230×109/L | 150–400 (×109/L) |
Haemoglobin | 150 g/L | Men: 135–177 (g/L)Women: 115–155 (g/L) |
PT | 11.8 seconds | 11.5–13.5 seconds |
APTT | 30 seconds | 26–37 seconds |
CRP | 80 mg/L | 0–5 (mg/L) |
Urea | 6 mmol/L | 2.5–6.7 (mmol/L) |
Creatinine | 100 μmol/L | 79–118 (μmol/L) |
Sodium | 140 mmol/L | 135–146 (mmol/L) |
Potassium | 4 mmol/L | 3.5–5.0 (mmol/L) |
eGFR | >60 mL/min | >60 (mL/min) |
Bilirubin | 10 μmol/L | <17 (μmol/L) |
ALT | 20 IU/L | <40 (IU/L) |
ALP | 40 IU/L | 39–117 (IU/L) |
Lactate | 1.5 mmol/L | 0.6–2.4 (mmol/L) |
Bicarbonate | 24 mmol/L | 22–26 (mmol/L) |
pH | 7.4 | 7.3–7.45 |
PaCO2 | 5 kPa | 4.8–6.1 (kPa) |
Initial Management [2]
Airway support: In this case, no intervention required. Consider intubation in any patient with a GCS<8
Supplementary oxygen: Give supplementary oxygen in any patient with saturations<94% or severe sepsis
Intravenous fluids: Intravenous fluids should be given to all patients with sepsis. In this case, the patient is given 0.9% saline at 125 mL/h. Reassess fluid status frequently and titrate fluid therapy as necessary. Once the urea and electrolytes are available, further fluids can be prescribed with supplementary potassium added as necessary
In a case of suspected meningitis, it is important to maintain neutral fluid balance–patients with sepsis should be given intravenous fluid therapy to maintain good tissue perfusion; however, overhydration can worsen raised intracranial pressure which occurs in meningitis
Antibiotics: The choice of antibiotics depends on the local antibiotic policy and early microbiological advice should be sought. Usually, a third generation cephalosporin is given as first line, e.g. cefotaxime 2 g IV 6-hourly. Atypical organisms should be considered in certain cases and advice from the microbiologist will be important in determining the most effective choice of antibiotics. In the elderly, consider Listeria infection which is covered by the addition of amoxicillin. If the patient has recently been abroad, they may have infection with penicillin-resistant pneumococci and you should add high-dose vancomycin
Corticosteroids: In cases of community-acquired meningitis (particularly pneumococcal meningitis), there is evidence that high-dose corticosteroids may reduce neurological complications if given before or at the same time as the first dose of antibiotics [3]. Following senior advice, consider starting dexamethasone 10 mg IV QDS. High-dose corticosteroids should not be given in those with meningococcal septicaemia, septic shock, in the immunosuppressed and those who have undergone recent neurosurgery. If corticosteroids are to be given, a proton pump inhibitor (such as omeprazole 40 mg IV OD) should be given in addition to prevent gastric ulceration
Antiviral treatment: In cases where encephalitis is suspected (headache, fever, seizures, altered personality, focal neurology), also give aciclovir 10 mg/kg IV TDS. It is reasonable to give it in the above case because of the patient’s confusion. Outcome in encephalitis significantly worsens the longer treatment is delayed; therefore, if you ever suspect encephalitis you should start treatment immediately–this can easily be stopped later when the viral PCR results are available
Analgesia: Start regular paracetamol for the patient’s headache. Use opioids with considerable caution in a patient with a reduced GCS
DVT prophylaxis treatment: pharmacological prophylaxis with LMWH should initially be avoided. Intracerebral and adrenal haemorrhage can both occur in meningitis as well as clotting abnormalities and consumption of platelets due to sepsis and disseminated intravascular coagulation. In all cases, LMWH treatment should be delayed until at least 6 hours after lumbar puncture. Following initial investigations and treatment, the appropriateness of LMWH prescription for DVT prophylaxis can be determined
Notify public health authority: Meningitis is a notifiable disease and close contacts should be treated with antibiotic prophylaxis–the choice of antibiotic depends on the causative organism and microbiology advice should be taken
Figure 5.1
Figure 5.2
Figure 5.3
Reassessment after Investigation Results
After initial assessment, a CT head is undertaken in view of the reduced GCS–this shows no evidence of intracranial mass or raised intracranial pressure. Lumbar puncture is therefore performed, the results of which are below:
WBC: 5000 cells/mm3 (95% polymorphs) | (normal range 0–5 cells/mm3) |
Protein 1 g/L | (normal range 0.15–0.5 g/L) |
Glucose 1.5 mmol/L (plasma was 4.5 mmol/L) | (normal range 0.6×plasma level) |
Interpreting lumbar puncture results
The lumbar puncture results are consistent with bacterial meningitis. Following discussion with the microbiology consultant, cefotaxime and dexamethasone are continued while awaiting CSF culture and sensitivities. Aciclovir is continued pending viral PCR results.
Handing over the Patient (in this case would likely be to intensive care)
‘Simon is a 22-year-old student with community acquired bacterial meningitis, on cefotaxime, aciclovir and dexamethasone.
He presented with headache, vomiting and neck stiffness. On examination, he is maintaining his own airway and is not in any respiratory distress. BP is 125/60 mmHg and pulse rate is 110 bpm. There are some signs of dehydration and he has been started on intravenous fluids. The GCS is 13/15: he is eye opening to voice and is confused but there are no focal neurological signs. The temperature is elevated at 38.1°C, there is no evidence of rash but he is Kernig’s positive. He has initially been treated with cefotaxime 2 g, dexamethasone 10 mg and aciclovir 750 mg.
Cerebrospinal fluid examination reveals a significantly raised white cell count predominantly of polymorphs. The protein is elevated and glucose level reduced.
The lumbar puncture results are typical of bacterial meningitis and, following microbiology advice, the plan is to continue current medications.
The patient is to be transferred to the intensive care unit for closer observation. The local public health authority has been informed and close contacts are being traced. Bloods are to be repeated in the morning and CSF/blood cultures need to be chased, as well as meningococcal and viral PCR.’
Station 5.2: Seizures
A 37-year-old female, Lucy, is brought in to the emergency department by ambulance following a collapse. She is currently having a generalized seizure while lying on a bed. The ambulance crew has just managed to place a cannula and ask if you want to give any medication. They report that Lucy has been seizing for about 10 minutes. She is not on any regular medications, and has never had a seizure before. Please assess her and instigate appropriate management.
Initial Assessment
Airway
Assess patency of the airway. In the case of a generalized seizure, it is critically important that the airway is protected and the patient is protected from injury. Open the airway and ensure it is patent. Is there any stridor or noisy breathing? Is there any vomit that could be obstructing the airway?
‘The patient is actively seizing and has therefore been placed in the recovery position. The airway is patent and unobstructed.’
First roll the patient onto their left side and into the recovery position if possible: if the patient vomits this will reduce the risk of aspiration. Ensure that the patient is not at risk of falling out of bed and call for a nurse to help assist you
If there is a history of trauma, use cervical spine precautions as necessary
Remove any loose fitting teeth but do not place anything in the mouth
If there are excess secretions or vomit use suction to clear the airway
Use head tilt, chin lift or jaw thrust manoeuvres as necessary to maintain the airway
Insert a nasopharyngeal airway with lubrication (unless there is a suspected basal skull fracture)
Intubation should be considered early if necessary and the on-call anaesthetist informed.
Breathing
Assess respiratory rate, oxygen saturations and accessory muscle use. Auscultate for air entry and additional sounds of wheeze or crepitations
‘The respiratory rate is 25/min, oxygen saturations are 100% on high-flow oxygen. There is accessory intercostal muscle use. The lung fields are clear to auscultation.’
Apply high-flow oxygen via a non-rebreather mask–make sure you inflate the reservoir bag with oxygen before placing it on the patient
High-flow oxygen therapy should be given to all patients who are having a generalized seizure unless there is a specific contraindication (e.g. known CO2 retainer). The respiratory rate is usually raised in the setting of a seizure. If oxygen saturations are reduced, consider performing an arterial blood gas–hypoxia can be a cause of seizures.
Figure 5.4
Figure 5.5
Figure 5.6
Circulation
Assess circulatory status by measuring pulse, blood pressure and capillary refill time
Perform a focused cardiovascular examination. Assess the central pulse and auscultate for heart sounds and any additional murmurs. Examine for evidence of peripheral oedema
‘The pulse is regular at 110 bpm, BP 155/90 mmHg, CRT is 1 second peripherally. Heart sounds are normal with no added murmurs. There is no evidence of peripheral oedema.’
The blood pressure and pulse are slightly elevated (possibly due to seizure activity). Obtain IV access and take bloods.
Disability
Attempt to assess the patient’s conscious level using either AVPU (is the patient Alert? If not, do they respond to Verbal or Painful stimuli? Or are they Unresponsive?) or the Glasgow Coma Scale. Check bedside glucose levels
‘The patient is actively seizing and it is therefore difficult to assess the GCS. The pupils are equal and reactive to light and the blood sugar is 5.1 mmol/L.’
It is important not to miss hypoglycaemia as a cause of seizures as it is easily treatable. Beware in those with malnutrition or alcoholics that intravenous glucose can precipitate Wernicke’s encephalopathy in the presence of thiamine deficiency–therefore give intravenous thiamine at the same time if this is suspected
Once the patient has stopped fitting it will be important to perform a full neurological examination to look for any deficits. Be aware, however, that following a seizure patients can have a Todd’s paresis–transient focal arm or leg weakness that occurs after a seizure
Ask the nursing staff to start the patient on neurological observations. Check pupil sizes and reactions.
Exposure
Expose the patient and in particular look for any evidence of rash that may indicate the underlying cause, e.g. petechial rash in meningococcal septicaemia, shingles associated with viral encephalitis. Examine for any obvious signs of injury
Measure the temperature. Examine the abdomen if possible to exclude any pathology
‘The temperature is 37.6°C, examination is otherwise unremarkable.’
Initial Investigations
Bloods: FBC, U&Es, LFTs, glucose, CRP, calcium, magnesium, and clotting. Look for evidence of infection or electrolyte abnormality that could have precipitated the seizure. Note that the white blood cell count will often go up secondary to a seizure in and of itself. Consider sending toxicology screen and if the patient is taking antiepileptic medications measure drug levels. If the patient is a woman of child-bearing potential send βHCG levels or perform a urinary pregnancy test after the seizure has terminated. If pregnancy is strongly suspected, perform an emergency ultrasound, or auscultate for a fetal heart: eclampsia usually doesn’t occur until about 20 weeks pregnancy so evidence of a baby should be present!
Blood cultures: Infection can precipitate seizures in those with epilepsy or be the primary cause; therefore blood cultures should be taken. If the temperature is elevated this may not always be due to infection as seizures themselves can lead to a rise in body temperature
Arterial blood gas: Perform an arterial blood gas if possible, otherwise a venous blood gas can be taken at the same time as cannulation. In particular, check for hypoxia, hyponatraemia and confirm normal glucose levels. Most blood gas machines will also analyse carboxyhaemoglobin levels, although carbon monoxide poisoning is a very rare cause of seizures
Respiratory and cardiac monitoring: Arrange for continuous monitoring of the BP, oxygen saturations and ECG tracing (to exclude arrhythmia). It is important to monitor for hypoxia during a seizure as well as changes in the pulse and BP. Some of the medications given to terminate seizures (e.g. phenytoin) can lead to arrhythmias and therefore continuous cardiac monitoring is required if these are given
Table 5.3
Ms Wall’s blood and ABG test results
Parameter | Value | Normal range (Units) |
WCC | 15×109/L | 4–11 (×109/L) |
Neutrophil | 8×109/L | 2–7.5 (×109/L) |
Lymphocyte | 5×109/L | 1.4–4 (×109/L) |
Platelet | 200×109/L | 150–400 (×109/L) |
Haemoglobin | 140 g/L | Men: 135–177 (g/L)Women: 115–155 (g/L) |
PT | 12 seconds | 11.5–13.5 seconds |
APTT | 30 seconds | 26–37 seconds |
CRP | 3 mg/L | 0–5 (mg/L) |
Urea | 6 mmol/L | 2.5–6.7 (mmol/L) |
Creatinine | 100 μmol/L | 79–118 (μmol/L) |
Sodium | 140 mmol/L | 135–146 (mmol/L) |
Potassium | 4 mmol/L | 3.5–5.0 (mmol/L) |
eGFR | >60 mL/min | >60 (mL/min) |
Bilirubin | 10 μmol/L | <17 (μmol/L) |
ALT | 14 IU/L | <40 (IU/L) |
ALP | 110 IU/L | 39–117 (IU/L) |
Glucose | 5 mmol/L | 4.5–5.6 (mmol/L) (fasting) |
Calcium | 2.23 mmol/L | 2.20–2.67 (mmol/L) |
Magnesium | 1 mmol/L | 0.7–1.1 (mmol/L) |
pH | 7.40 | 7.35–7.45 |
PaO2 | 12.0 kPa on air | 10.6–13.3 (kPa) on air |
PaCO2 | 5.0 kPa | 4.8–6.1 (kPa) |
HCO3 | 24 mmol/L | 22–26 (mmol/L) |
‘Bloods show a raised white cell count, but are otherwise normal, including the arterial gas.’
Initial Management [4]
Seek senior help early in the event of a seizure
Airway support: Place in the recovery position, perform airway manoeuvres as needed and insert a nasopharyngeal airway. Consider intubation if needed
Obtain IV access and perform ABG (or venous gas if ABG not possible)
Terminating the seizure: Many seizures self-terminate without intervention; however, if the seizure is prolonged (i.e. greater than 5 minutes), treatment should be given to prevent hypoxic brain injury. In reality, if the patient hasn’t stopped seizing by the time you have performed all of the above, 5 minutes is likely to have passed and you should give medication to terminate the seizure:
The initial choice is a benzodiazepine, e.g. lorazepam 4 mg IV (as a slow injection over 2 minutes). Be aware that benzodiazepines can cause respiratory depression so have resuscitation equipment and flumazenil available in case they are needed. If it is not possible to obtain IV access then diazepam 10 mg can be given rectally or midazolam 10 mg buccally
The blood sugar should have already been checked and hypoglycaemia corrected
In all alcoholics and those who are malnourished, consider thiamine deficiency and give replacement with intravenous thiamine, e.g. Pabrinex® IV High Potency Injection (ampoules 1 and 2) IV
If the patient is pregnant check the BP and consider eclampsia. Call for senior help immediately and contact the obstetric registrar on call. Following senior advice, treatment would consist of magnesium sulphate 4 g in 100 mL 0.9% saline given over 5 minutes with continuous respiratory and cardiac monitoring [2]
If after 10 minutes the patient is still seizing then repeat the same dose of benzodiazepine
If despite 2 doses of benzodiazepines the patient continues to seize, load with phenytoin 20 mg/kg intravenously. Phenytoin should be given through a large bore intravenous cannula followed by a flush of 0.9% saline as it can cause venous irritation. It is given at a maximum rate of 50 mg/minute. It is diluted in 0.9% saline and the concentration should not exceed 10 mg/mL–therefore usually doses of 1000 mg or less are made up in 100 mL, and doses above 1000 mg in 250 mL of 0.9% saline. Continuous monitoring of observations and ECG is necessary during phenytoin infusion and the infusion should be slowed or stopped if there is a fall in blood pressure or arrhythmias develop. If the patient was already taking phenytoin then phenobarbital may be used as an alternative.

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