Neurogenic shock

(Redirected from Neurogenic Shock)

Background

  • Do not confuse with spinal shock
  • Diagnosis of exclusion
    • Never presume hypotension in trauma patient is due to neurogenic shock
  • Injury to cervical or thoracic vertebrae causes peripheral sympathetic denervation
    • Above T1: full sympathetic denervation
    • T1-L3: Partial sympathetic denervation
    • Below L4: no sympathetic denervation
  • Lasts 1-3 week

Clinical Features

Differential Diagnosis

Shock

Neck Trauma

Evaluation

Workup

Diagnosis

Management

Neurogenic Shock Management

Exclude other causes of shock!

  • Judicious IVF with normal saline, with UOP >30 cc/hr
    • Hypotonic fluids such as D5W and 0.45% NS are contraindicated
    • Albumin is relatively contraindicated as compared to NS[1]
  • Norepinephrine first line, with MAP goal of 85-90 for the first 5-7 days after spinal cord injury[2]
    • Consider adding phenylephrine if BP refractory to first line agent
    • Phenylephrine alone without beta-1 stimulation will cause reflex bradycardia
    • Atropine if needed, keeping HR 60-100 bpm in NSR
    • May titrate down on norepinephrine and atropine, to favor more phenylephrine α agonism in ICU setting

Acute Management of Spinal Cord Injury

  • Neurogenic shock management
  • Consider intubation injuries at C5 or above
    • Manual in-line stabilization reduces cervical movement better than C-collar, but be careful of tracheal pressures inadvertently applied which can worsen laryngeal visualization[3][4]
    • Direct laryngoscopy causes C-spine extension at atlanto-occipital junction, C1-C2, and C4-C7 in order from most to least
    • Consider video laryngoscopy with hyperangulated stylet or bougie assisted DL to intubate higher-grade laryngoscopy views of vocal cords without C-spine overextension[5]
    • Post-intubation sedation takes into consideration hemodynamics and potential intraoperative EMG and evoked potential monitoring by anesthesia
  • Consider surgical intervention for:
  • Steroids are no longer recommended
    • Administration of methylprednisolone (MP) for the treatment of acute spinal cord injury (SCI) is not recommended. Clinicians considering MP therapy should bear in mind that the drug is NOT approved by the FDA for this indication. There is no Class I or Class II medical evidence supporting the clinical benefit of MP in the treatment of acute SCI. Scattered reports of Class III evidence claim inconsistent effects likely related to random chance or selection bias. However, Class I, II, and III evidence exists that high-dose steroids are associated with harmful side effects including death.[8]
    • See EBQ:High Dose Steroids in Cord Injury for further discussion

Additional Considerations

  • Prevent hypothermia - consider temperature probe Foley
  • High risk of VTE in paraparesis or tetraparesis
    • Up to 40% in non-prophylaxed
    • Must weigh benefits of VTE prophylaxis and risk of bleed from LMWH
    • Low dose SC heparin at 500 units q8hrs plus SCDs may be alternative

See Also

External Links

References

  1. A comparison of albumin and saline for fluid resuscitation in the intensive care unit. Finfer S, Bellomo R, Boyce N, French J, Myburgh J, Norton R, SAFE Study Investigators. N Engl J Med. 2004 May 27; 350(22):2247-56.
  2. Blood pressure management after acute spinal cord injury. Hadley MN, Walters BC, Grabb PA, Oyesiku NM, Przybylski GJ, Resnick DK, Ryken TC. Neurosurgery. 2002 Mar; 50(3 Suppl):S58-62.
  3. The effect of laryngoscopy of different cervical spine immobilisation techniques. Heath KJ. Anaesthesia. 1994 Oct; 49(10):843-5.
  4. Manual in-line stabilization increases pressures applied by the laryngoscope blade during direct laryngoscopy and orotracheal intubation. Santoni BG, Hindman BJ, Puttlitz CM, Weeks JB, Johnson N, Maktabi MA, Todd MM. Anesthesiology. 2009 Jan; 110(1):24-31.
  5. Cervical spinal motion during intubation: efficacy of stabilization maneuvers in the setting of complete segmental instability. Lennarson PJ, Smith DW, Sawin PD, Todd MM, Sato Y, Traynelis VC. J Neurosurg. 2001 Apr; 94(2 Suppl):265-70.
  6. Improvement of motor-evoked potentials by ketamine and spatial facilitation during spinal surgery in a young child. Erb TO, Ryhult SE, Duitmann E, Hasler C, Luetschg J, Frei FJ. Anesth Analg. 2005 Jun; 100(6):1634-6.
  7. Effects of dexmedetomidine on intraoperative motor and somatosensory evoked potential monitoring during spinal surgery in adolescents. Tobias JD, Goble TJ, Bates G, Anderson JT, Hoernschemeyer DG. Paediatr Anaesth. 2008 Nov; 18(11):1082-8.
  8. Hurlbert RJ et al. Pharmacological therapy for acute spinal cord injury. Neurosurgery. 2013 Mar;72 Suppl 2:93-105 http://www.ncbi.nlm.nih.gov/pubmed/23417182