Thanks to Dr Joanna Middleton for leading the discussion this month and providing these tips and references.
Edited by Dr David Lewis
Top tips from this month’s rounds:
Incomprehensible Patient – Delirium or Aphasia?
Pediatric Trauma
CME QUIZ
Take Home Points
- Sudden onset language impairment should be assumed to be aphasia until proven otherwise
- Aphasia is most commonly caused by CVA and usually has associated lateralising motor signs (but not always)
- Aphasic patients will be able to perform non-verbal tasks normally
- If in doubt involve telestroke / neurology early
- Global aphasia can have a catastrophic outcome on quality of life. In selected patients, early thrombolysis can significantly improve prognosis.
- The injuries sustained by children in chest trauma are frequently different from adults
- Signs of shock in pediatric trauma can be subtle
- Use evidence based guidelines e.g PECARN when considering CT for abdominal trauma
- Elevated Tropinin or abnormal ECG suggest blunt cardiac injury
Incomprehensible Patient – Delirium or Aphasia?
Both can present with disorders of speech and language, however it is important to rapidly distinguish aphasia due to it’s association with stroke and the benefits of early thrombolysis.
Delirium, also known as acute confusional state, is an organically caused decline from a previously baseline level of mental function. It often has a fluctuating course, attentional deficits, and disorganization of behaviour including speech and language.
Aphasia is an impairment of language, affecting the production or comprehension of speech and the ability to read or write. Aphasia is always due to injury to the brain, most commonly from a stroke, but also trauma, tumour or infection.
The first tip here is to figure out how to describe the features of a patient’s language. How is the patient’s language produced and understood?
Are the words clearly enunciated (favoring aphasia) or slurred (favoring delirium)?
Is the patient’s speech grammatically correct (delirium) or lacking in appropriate syntax (aphasia)?
Is the patient’s prosody—or pattern of speech—fluent (delirium) or irregular (aphasia)?
Can the patient understand spoken language (delirium) or is there a major difficulty with following simple verbal/written commands (aphasia)?
Naming and repetition should also be assessed as part of any neurologic examination, but impairment in these modalities is not as useful in distinguishing delirium from aphasia.
The motor evaluation of inattention in a delirious patient involves testing for asterixis, either with arms and wrists fully extended or having the patient squeeze the fingers of the examiner (the “milk maid’s sign”). A delirious patient will struggle with these tasks, the extended hands may flap or the fingers may intermittently lose their grip. The aphasic patient, in contrast, may not have trouble with this.
Global Aphasia
- Severe impairment of production, comprehension and repetition of language
- Usually large CVA of left MCA
- Usually associated with extensive perisylvian injury affecting both Broca’s and Wernicke’s areas
- Usually accompanied by right hemiparesis and often a right visual field deficit (in right handed pt)
- Patients with global aphasia can be shown to perform normally on nonverbal tasks such as picture matching, demonstrating they are not suffering from confusion or dementia
- Lateralising motor signs may be extremely subtle and on rare occasions may not be present (Global aphasia without hemiparesis: A case series).
Stroke Thrombolysis – Indications and Contraindications Reminder
Patient Selection for Thrombolytic Therapy in AIS:
Inclusion criteria: Patients >18 years of age with symptoms of AIS and a measurable neurological deficit with time of onset <4.5 h.
Exclusion criteria:
A. History
- History of intracranial hemorrhage
- Stroke, serious head injury or spinal trauma in the preceding 3 months
- Recent major surgery, such as cardiac, thoracic, abdominal, or orthopedic in previous 14 days
- Arterial puncture at a non-compressible site in the previous 7 days
- Any other condition that could increase the risk of hemorrhage after rt-PA administration
B. Clinical
- Symptoms suggestive of subarachnoid hemorrhage
- Stroke symptoms due to another non-ischemic acute neurological condition such as seizure with post-ictal Todd’s paralysis or focal neurological signs due to severe hypo- or hyperglycemia
- Hypertension refractory to antihypertensives such that target blood pressure <185/110 cannot be achieved
- Suspected endocarditis
C. Laboratory
- Blood glucose concentration below 2.7 mmol/L or above 22.2 mmol/L
- Elevated activated partial-thromboplastin time (aPTT)
- International Normalized Ratio (INR) greater than 1.7
- Platelet count <100 x 109/L
- Current use of direct thrombin inhibitors or direct factor Xa inhibitors with elevated insensitive global coagulation tests (aPTT for dabigatran, INR for rivaroxaban) or a quantitative test of drug activity (Hemoclot® for dabigatran, specific anti-factor Xa activity assays for rivaroxaban, apixaban and edoxaban). In this situation, endovascular treatment (thrombectomy) should be considered if patient eligible.
D. CT or MRI Findings
- Any hemorrhage on brain CT or MRI
- CT showing early signs of extensive infarction (hypodensity more 1/3 of cerebral hemisphere), or a score of less than 5 on the Alberta Stroke Program Early CT Score [ASPECTS], or MRI showing an infarct volume greater than 150 cc on diffusion-weighted imaging.
Relative contraindications for rt-PA therapy in AIS include the following:
- Recent myocardial infarction with suspected pericarditis
- Rapidly improving stroke symptoms
- Pregnancy or post-partum period
- Recent GI or urinary tract hemorrhage (within 21 days)
Take Home Points
- Sudden onset language impairment should be assumed to be aphasia until proven otherwise
- Aphasia is most commonly caused by CVA and usually has associated lateralising motor signs (but not always)
- Aphasic patients will be able to perform non-verbal tasks normally
- If in doubt involve telestroke / neurology early
- Global aphasia can have a catastrophic outcome on quality of life. In selected patients, early thrombolysis can significantly improve prognosis.
Pediatric Trauma
Some specific issues particular to pediatric trauma are highlighted:
Pediatric Chest Trauma
Children have compliant chests and thus sustain musculoskeletal thoracic injuries far less frequently (5% of traumas). However, due to this elasticity, the most common injury is a pulmonary contusion.
Don’t expect traditional adult injury findings: Absence of chest tenderness, crepitus and flail chests does not preclude injury.
Bendy ribs – injury to internal organs with little external evidence
Lung contusions ~50% of chest trauma
Force transmitted to lung parenchyma – lung lacerations much less common <2%
Pediatric Abdominal Trauma
Beware: 20-30% of pediatric trauma patients with a “normal” abdominal exam will have significant abdominal injuries on imaging.
Any polytrauma patient with hemodynamic instability should be considered to have a serious abdominal injury until proven otherwise. Tachycardia primary reflex for kids in response to hypovolemia and it may be the only sign of shock.
HIGH RISK – Indications for CT
• History that suggests severe intra-abdominal injury e.g abrupt acceleration/deceleration, pedestrian vs vehicle, handlebar injury, fall from horse etc
• Concerning physical – tenderness, peritoneal signs, seatbelt sign or other bruising
• AST >200 or ALT >125
• Decreasing Hb or Hct
• Gross hematuria
• Positive FAST
PECARN
The Pediatric Emergency Care Applied Research Network (PECARN) network derived a clinical prediction rule to identify children (median age, 11 years) with acute blunt torso trauma at very low risk for having intra-abdominal injuries (IAIs) that require acute intervention.
The prediction rule consisted of (in descending order of importance)
- no evidence of abdominal wall trauma or seat belt sign
- Glasgow Coma Scale score greater than 13
- no abdominal tenderness
- no evidence of thoracic wall trauma
- no complaints of abdominal pain
- no decreased breath sounds
- no vomiting
The rule had a negative predictive value of 5,028 of 5,034 (99.9%; 95% confidence interval [CI] 99.7% to 100%), sensitivity of 197 of 203 (97%; 95% CI 94% to 99%), specificity of 5,028 of 11,841 (42.5%; 95% CI 41.6% to 43.4%), and negative likelihood ratio of 0.07 (95% CI 0.03 to 0.15).
Blunt Cardiac Injury
Largest pediatric case series of BCI – 184 patients – 95% had simple cardiac contusions. https://www.ncbi.nlm.nih.gov/pubmed/8577001
The clinical presentation of blunt cardiac injury varies. Mild injuries may present without objective findings, while some patients may have minor dysrhythmias.
A normal ECG and troponin I during the first 8 hours of hospital stay rules out blunt cardiac injury, and the negative predictive value of combining these 2 simple tests was 100%. https://www.ncbi.nlm.nih.gov/pubmed/12544898
Traumatic Tricuspid Injuries
Location, location, location
RV posterior to sternum – blunt force elevates pressures resulting in rupture of chordae, papillary muscle injury or tear of leaflet
Most frequent associated injury: pulmonary contusion
“The presence of a transient right bundle branch block in the setting of myocardial contusion is a described, but under-recognized occurrence.”
“Although an rsr’ in the right precordial leads may be normal in children, it’s combination with an abnormal frontal axis (“bifasicular block”) is always abnormal and suggest injury to the RV”
Take Home Points
- The injuries sustained by children in chest trauma are frequently different from adults
- Signs of shock in pediatric trauma can be subtle
- Use evidence based guidelines e.g PECARN when considering CT for abdominal trauma
- Elevated Tropinin or abnormal ECG suggest blunt cardiac injury
CME QUIZ
EM Reflections - Dec 17 - CME Quiz
EM Reflections – Dec 17 – CME Quiz