VP Shunt Malfunction - Emergency Management

Algorithm Steps

1. ▶

   Start

   VP Shunt Patient with Concerning Symptoms

   Headache, vomiting, lethargy, seizure, AMS, or neurological decline in shunted patient

   1. ◆

      Decision

      Hemodynamically Unstable or Signs of Herniation?

      Assess for impending or active herniation

      • Cushing triad: hypertension, bradycardia, irregular breathing
      • Posturing (decerebrate/decorticate)
      • Fixed dilated pupil(s)
      • GCS ≤8 or rapid decline
      • Unresponsive or seizing
      1. ⚠

         Warning

         ⚠️ EMERGENT ICP MANAGEMENT

         Impending herniation - act immediately

         • Call neurosurgery STAT
         • Elevate head of bed 30°
         • Consider emergent intubation (avoid ketamine, succinylcholine)
         • Pretreat: Fentanyl 1 mcg/kg, Lidocaine 1 mg/kg
         • Sedate: Propofol or Etomidate
         • Hyperventilate to pCO2 30-35 mmHg temporarily
         1. ●

            Action

            Hyperosmolar Therapy

            Reduce ICP while awaiting definitive care

            • Mannitol 0.5-1 g/kg IV (20% solution)
            • OR Hypertonic saline 3% 250mL bolus
            • OR 23.4% saline 30mL via central line
            • Maintain Na+ 145-155 mEq/L if using HTS
            1. ●

               Action

               Consider Emergent Shunt Tap

               Decompress if neurosurgery unavailable and herniation imminent

               • Locate reservoir (palpable under scalp)
               • Sterile prep, 23-25G butterfly needle
               • Insert perpendicular to reservoir
               • Allow passive CSF drainage (do not aspirate)
               • Send CSF for cell count, culture, glucose, protein
               1. ●

                  Action

                  Neurosurgery Consultation

                  Definitive management for shunt malfunction

                  • Shunt revision if obstruction confirmed
                  • May need new shunt placement
                  • Consider EVD as temporizing measure
                  1. ✓

                     Outcome

                     Disposition Based on Findings

                     Admit for shunt revision/treatment OR discharge with close follow-up

      2. ●

         Action

         Systematic Workup

         For stable patients with shunt concern

         • Full neurological exam
         • Document baseline mental status
         • Palpate shunt reservoir and tract
         • Check for signs of infection along tract
         1. ●

            Action

            Imaging Studies

            CT brain and shunt series

            • CT head without contrast
            • Compare to baseline if available
            • Shunt series (AP/Lat skull, chest, abdomen)
            • Look for: ventricular size, disconnection, migration
            1. ◆

               Decision

               CT Findings?

               Evaluate for signs of malfunction

               • Enlarged ventricles vs baseline = obstruction
               • Slit ventricles = possible over-drainage
               • Note: 15% of malfunctions have NO CT change
               • Periventricular edema suggests acute obstruction
               1. ●

                  Action

                  Ventricular Enlargement

                  Likely proximal (ventricular) or distal obstruction

                  • Consult neurosurgery urgently
                  • May need shunt tap to assess
                  • Prepare for possible OR
                  1. ◆

                     Decision

                     Signs of Shunt Infection?

                     Fever, meningismus, erythema along tract, CSF pleocytosis

                     1. ●

                        Action

                        Shunt Infection Management

                        Antibiotics and neurosurgery consult

                        • Vancomycin + Cefepime (or Meropenem)
                        • Cover Staph epidermidis, S. aureus, gram negatives
                        • Neurosurgery for externalization or removal
                        • Often requires complete shunt removal
               2. ◆

                  Decision

                  Clinical Suspicion Still High?

                  Symptoms concerning despite normal CT

                  1. ●

                     Action

                     Shunt Tap for Diagnosis

                     Assess function and rule out infection

                     • Opening pressure: normal 5-15 cmH2O
                     • Elevated: distal obstruction
                     • Low/absent: proximal obstruction
                     • Send CSF: cell count, culture, glucose, protein
                  2. ●

                     Action

                     Consider Alternative Diagnosis

                     If CT normal and clinical suspicion low

                     • Migraine/headache in shunt patient
                     • Viral illness
                     • Other causes of symptoms
                     • Still consult neurosurgery if uncertain