Neurology: Herniation Pathway and Care

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

The upper limit of osmolarity for hypertonic saline is approximately ______ mOsm/L.

360

What is a potential alternative to hypertonic saline in managing raised ICP?

mannitol

What is the minimum acceptable value for CPP?

30 mm Hg

50 mm Hg

40 mm Hg (correct)

60 mm Hg

The use of mannitol is well-documented in treating increased ICP.

False Signup and view all the answers

What should be monitored to detect abnormalities influencing therapeutic decisions?

Arterial blood gases, serum electrolytes, osmolarity, blood urea nitrogen, serum creatinine, hemoglobin, MAP, temperature, end-tidal CO2 Signup and view all the answers

What is the suggested range for CVP in maintaining appropriate intravascular volume status?

4 to 10 mm Hg Signup and view all the answers

Match the following CPP thresholds with their targeted population:

Lower end = Infants Upper end = Adolescents Minimum value = 40 mm Hg Possible higher values = Cerebral hypoperfusion/ischemia Signup and view all the answers

What should be maintained to manage raised intracranial pressure (ICP)?

All of the above Signup and view all the answers

What indicates impending or ongoing cerebral herniation?

Acute changes in neurological signs such as pupillary dilation and altered motor responses. Signup and view all the answers

Decerebrate rigidity reflects impaired brainstem activity between the midbrain and medulla.

False Signup and view all the answers

What is the recommended fluid volume for pediatric patients with severe TBI?

At least 75% of maintenance fluids. Signup and view all the answers

Which monitoring technique is less commonly used in severe TBI management?

Cerebral perfusion pressure (CPP) monitoring Signup and view all the answers

Manual hyperventilation with Fio2 of _____ should be administered during herniation management.

1.0 Signup and view all the answers

What is the initial target ICP level that requires intervention?

Greater than 20 mm Hg Signup and view all the answers

What is the optimal management in a patient with a functioning external ventricular drain (EVD) during herniation?

Open the drain for continuous drainage. Signup and view all the answers

Protocols advise a target arterial oxygen tension (Pao2) of less than 80 mm Hg.

False Signup and view all the answers

Match the condition with its clinical sign related to herniation:

Transtentorial herniation = Pupillary dilatation and bradycardia Foramen magnum herniation = Downbeat nystagmus and bradycardia Subfalcine herniation = Unilateral or bilateral weakness Retroalar herniation = Hemiplegia Signup and view all the answers

Study Notes

Herniation Pathway

Herniation can occur at any time in the ICP pathway: on presentation, in the course of progressive intracranial hypertension, or precipitously.
Signs of herniation: pupillary dilation, bradycardia, downbeat nystagmus, bradycardia, bradypnea, hypertension, unilateral or bilateral weakness, hemiplegia, inappropriate motor responses to pain.
Decorticate rigidity reflects impaired brainstem activity down to the red nucleus.
Decerebrate rigidity reflects impaired brainstem activity between the rostral midbrain and mid-pons.
Emergency medical management of herniation: manual hyperventilation with Fio2 of 1.0, mannitol (0.5–1 g/kg) or hypertonic saline (3%, 1–3 mL/kg).

Baseline Care

Consists of 9 components including analgesia, sedation, controlled mechanical ventilation, normothermia, appropriate intravascular volume status, minimum blood hemoglobin, treatment of coagulopathy, neutral head positioning, antiepileptic drug therapy, continuous electroencephalography.
Most protocols use a benzodiazepine and opiate combination for sedation.
Ventilation targets: Spo2 >92%, Pao2 90–100 mm Hg, Paco2 35–40 mm Hg.
Temperature target: normothermia, less than 38°C.
Normovolemia with central venous pressure (CVP) monitoring, urine output, blood urea nitrogen, serum creatinine, and clinical examination.
Hemoglobin target: greater than 7.0 g/dL.
Coagulopathy treatment with fresh frozen plasma, but caution is advised as overresuscitation may worsen coagulopathy.
Neutral head positioning with head-of-bed elevated to 30°.

First Tier Therapies

ICP pathway: initial ICP target less than 20 mm Hg.
Intervention threshold for ICP: greater than 20 mm Hg for at least 5 minutes.
Management of raised ICP: CSF drainage, hypertonic saline, mannitol, analgesia, sedation, neuromuscular blockade.
Key physiological variables to monitor: arterial blood gases, serum electrolytes, osmolarity, blood urea nitrogen, serum creatinine, hemoglobin, MAP, temperature, and end-tidal CO2.

Cerebral Perfusion Pressure (CPP) Pathway

CPP can be maintained despite increased ICP. This is often observed in clinical practice.
Minimum CPP value: The Third Edition Guidelines recommend a minimum CPP of 40 mmHg.
Age-specific CPP thresholds: Considerations for using age-specific CPP thresholds between 40 and 50 mmHg are suggested.
- Infants: Lower end of the range.
- Adolescents: Upper end of the range.
Higher CPP values may be desirable to prevent patients from falling below the minimum thresholds and experiencing cerebral hypoperfusion/ischemia.
CPP-directed interventions: Focus on maintaining adequate intravascular volume status.
- CVP (central venous pressure) should be maintained between 4 and 10 mmHg.
MAP and SBP targets: Some protocols recommend targeting MAP or systolic blood pressure (sBP) based on age and specific ranges.
- Normal blood pressure for age: 50th percentile MAP
- MAP targets: Greater than 65 mmHg, greater than 90 mmHg, or between 100 and 110 mmHg.
- sBP targets: Greater than "70 + (2 × age in years)" mmHg, greater than 95 mmHg, but maintained below 140 mmHg.
- Committee recommendation: Support for a targeted approach to managing CPP.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers critical concepts related to the herniation pathway in neurology, including signs of herniation and emergency medical management techniques. You will also explore baseline care components crucial for patient management. Test your knowledge on these vital neurological principles!