Difference between revisions of "Ventriculoperitoneal shunt problems"

(Text replacement - " US " to " ultrasound ")
 
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===Adults===
 
===Adults===
*Cephalgia, [[nausea and vomiting]], lethargy, [[ataxia]], [[altered mental status]]
+
*[[headache|Cephalgia]], [[nausea and vomiting]], [[lethargy]], [[ataxia]], [[altered mental status]]
 
*Paralysis of upward gaze ("sunset eyes"), dilated pupils, [[cranial nerve palsies]]
 
*Paralysis of upward gaze ("sunset eyes"), dilated pupils, [[cranial nerve palsies]]
  
 
===Infants===
 
===Infants===
*Vomiting, irritability, bulging fontanelle
+
*[[nausea and vomiting (peds)|Vomiting]], irritability, [[bulging fontanelle]]
 
**Often '''very subtle''': a caregiver-reported change in behavior predicts malfunction
 
**Often '''very subtle''': a caregiver-reported change in behavior predicts malfunction
 +
 +
 +
===Physical Exam===
 +
*Neither sensitive nor specific
 +
*[[AMS|Decreased level of consciousness]], erythema along shunt tract, [[bulging fontanelle]], [[nausea/vomiting]], irritability should raise suspicion
 +
*Valve chamber abnormality
 +
**Gently compress chamber and observe for refill
 +
**Difficulty compressing chamber indicates distal flow obstruction
 +
**Slow refill (>3s) indicates proximal obstruction
  
 
==Differential Diagnosis==
 
==Differential Diagnosis==
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==Evaluation==
 
==Evaluation==
*Physical Exam
 
**Neither Sn nor Sp
 
**Decreased level of consciousness, erythema along shunt tract, buldging fontanel, nausea/vomiting, irritability should raise suspicion
 
*Valve chamber abnormality
 
**Gently compress chamber and observe for refill
 
**Difficulty compressing chamber indicates distal flow obstruction
 
**Slow refill (>3s) indicates proximal obstruction
 
===Work Up===
 
 
*CBC, Chem7, coags
 
*CBC, Chem7, coags
 
*Blood cultures
 
*Blood cultures
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***AP and lateral skull, AP chest and abdomen
 
***AP and lateral skull, AP chest and abdomen
 
***Identifies kinking, migration, or disconnection
 
***Identifies kinking, migration, or disconnection
**CT
+
**[[head CT|CT]]
 
***Needed to evaluate ventricular size (if larger, concerning for elevated ICP)
 
***Needed to evaluate ventricular size (if larger, concerning for elevated ICP)
 
***Very helpful to compare to previous study (many patients with shunts have abnormal baseline)
 
***Very helpful to compare to previous study (many patients with shunts have abnormal baseline)
 
***One-third of patients with shunt malfunction will have normal head CT{{Citation needed|reason=Reliable source needed|date=March 2016}}
 
***One-third of patients with shunt malfunction will have normal head CT{{Citation needed|reason=Reliable source needed|date=March 2016}}
**US
+
**[[Ultrasound]]
 
***If the baby has an open fontanelle, you may use US
 
***If the baby has an open fontanelle, you may use US
 
***Some literature for [[ultrasound]] of optic nerve diameter (if normal (3.3cm), lower chance of elevated ICP){{Citation needed|reason=Reliable source needed|date=March 2016}}
 
***Some literature for [[ultrasound]] of optic nerve diameter (if normal (3.3cm), lower chance of elevated ICP){{Citation needed|reason=Reliable source needed|date=March 2016}}

Latest revision as of 23:51, 1 October 2019

Background

Diagram showing a brain shunt CRUK 052.svg.png
  • Also called a cerebral sinus fluid (CSF), VP, or cerebral shunt
  • Highest incidence of postoperative complications of any neurosurgical procedure
    • Majority in the first 2 years (40% in the first year[1])
  • May drain into peritoneal cavity or less commonly the right atrium, pleural cavity, ureter, gallbladder
Vpvalve.png

Clinical Features

  • Develop over several days

Adults

Infants


Physical Exam

  • Neither sensitive nor specific
  • Decreased level of consciousness, erythema along shunt tract, bulging fontanelle, nausea/vomiting, irritability should raise suspicion
  • Valve chamber abnormality
    • Gently compress chamber and observe for refill
    • Difficulty compressing chamber indicates distal flow obstruction
    • Slow refill (>3s) indicates proximal obstruction

Differential Diagnosis

Ventriculoperitoneal shunt problems

Loculation of Ventricles

  • Separate, noncommunicating CSF accumulations may develop within a ventricle
    • Shunt device unable to drain entire ventricular system leading to increased ICP

Abdominal Complications

  • Pseudocyst may form around the peritoneal catheter
    • Can lead to occlusion and/or abdominal pain (depending on size)

Evaluation

  • CBC, Chem7, coags
  • Blood cultures
  • Shunt tap if concerned for infection (this is usually done by or in consultation with neurosurgery)
    • A normal lumbar puncture does not rule out ventriculitis (shunt infection)
  • Imaging
    • Shunt series
      • AP and lateral skull, AP chest and abdomen
      • Identifies kinking, migration, or disconnection
    • CT
      • Needed to evaluate ventricular size (if larger, concerning for elevated ICP)
      • Very helpful to compare to previous study (many patients with shunts have abnormal baseline)
      • One-third of patients with shunt malfunction will have normal head CT[citation needed]
    • Ultrasound
      • If the baby has an open fontanelle, you may use US
      • Some literature for ultrasound of optic nerve diameter (if normal (3.3cm), lower chance of elevated ICP)[citation needed]

Management

  • Assume shunt malfunction in patients with suggestive features regardless of findings on imaging
  • Revisions are extremely common, low threshold to contact Neurosurgery
  • Ventriculoperitoneal shunt drainage

Disposition

See Also

References

  1. Drake JM, Kestle JRW, Tuli S. CSF shunts 50 years on past, present and future. Child’s Nerv Syst. 2000; 16:800–804.