Abstract
Introduction
The medical literature is lacking in data regarding intracranial pressure in an animal model with concomitant vagus nerve and spinal cord stimulation.
Methods
Ten pigs were anesthetized and placed in the supine position and an intracranial pressure monitor was inserted. Each study animal had a small laminectomy performed in the lumbar region and the left vagus nerve exposed within the carotid sheath. Intracranial pressure was monitored for 3 h in all animals. Eight animals at the end of 3 h of monitoring underwent vagus nerve stimulation and or spinal cord stimulation. Study and control animals had their intracranial pressure monitored for an additional 1 and 2 h respectively.
Results
Following vagus nerve stimulation, all animals had significant (p<0.05) decreases in their intracranial pressure with a lasting effect of 15–35 min (mean 18.5 min). No significant change in blood pressure was noted during stimulation of the vagus nerve. After spinal cord stimulation all animals responded with acute increases in their intracranial pressure (p<0.05).
Conclusions
Left vagus nerve stimulation reliably decreases intracranial pressure in the pig. The mechanism of this action remains unclear and does not appear to be due to resultant bradycardia. Conversely, stimulation of the upper lumbar spinal cord increases intracranial pressure with simultaneous increases in heart rate. Following additional studies and with close observation of cerebral perfusion pressure, we believe that left vagus nerve stimulation may represent a novel adjunctive therapy for decreasing elevated intracranial pressure in posttraumatic human patients with head injuries. Additionally, according to this animal data, minimizing spinal cord stimulation should be considered in the acute setting following head injury so as to minimize iatrogenic elevation of intracranial pressure.
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References
Bakay RAE (1996) Vagus nerve stimulation activates central nervous system structures in epileptic patients during PET H2O blood flow imaging [comment]. Neurosurgery 39:430–431
Ebel H, Semmelmann G, Friese M et al (2001) Effects of electrical stimulation of the Gasserian ganglion on regional cerebral blood flow after induced subarachnoid hemorrhage in pigs evaluated by 99mTc-HMPAO-SPECT. Minim Invasive Neurosurg 44:50–57
Garnett ES, Nahmias C, Scheffel A et al (1992) Regional cerebral blood flow in man manipulated by direct vagal stimulation. Pacing Clin Electrophysiol 15:1579–1580
Hagl C, Khaladj N, Weisz DJ et al (2002) Impact of high intracranial pressure on neurophysiological recovery and behavior in a chronic porcine model of hypothermic circulatory arrest. Eur J Cardiothorac Surg 22:510–516
Hammond EJ, Uthman BM, Reid SA et al (1992) Electrophysiological studies of cervical vagus nerve stimulation in humans: I-EEG effects. Epilepsia 33:1013–1020
Hammond EJ, Uthman BM, Reid SA (1992) Neurochemical effects of vagus nerve stimulation in humans. Brain Res 583:300–303
Handforth A, DeGirogio CM, Schachter SC et al (1998) Vagus nerve stimulation for partial-onset seizures: a randomized active-control trial. Neurology 51:48–55
Henry TR, Bakay RAE, Votaw JR et al (1997) Acute vagus nerve stimulation selectively alters blood flow in somatosensory and limbic cortex and the cerebellum of patients with complex partial seizures [abstract]. Epilepsia 38 [Suppl 8]:144
Josephs LG, Est-McDonald JR, Birkett DH et al (1994) Diagnostic laparoscopy increases intracranial pressure. J Trauma 36:815–818
Kamath MV, Upton ARM, Talalla A et al (1992) Neurocardiac responses to vagoafferent electrostimulation in humans. Pacing Clin Electrophysiol 15:1581–1587
Lockard JS, Congdon WC, DuCharme LL (1990) Feasibility and safety of vagal stimulation in monkey model. Epilepsia 31:S20–S26
Meyer G, Winter DL (1970) Spinal cord participation in the Cushing reflex in the dog. J Neurosurg 33:662–675
McLachlan RS (1993) Suppression of interictal spikes and seizures by stimulation of the vagus nerve. Epilepsia 34:918–923
Naritoku DK, Morales A, Pencek TL et al (1992) Chronic vagus nerve stimulation increases the latency of the thalamocortical somatosensory evoked potential. Pacing Clin Electrophysiol 15:1572–1578
NIH Consensus Conference (1990) Surgery for epilepsy. JAMA 264:729–733
Penry JK, Dean JC (1990) Prevention of intractable partial seizures by intermittent vagal stimulation in humans: preliminary results. Epilepsia 31:40–43
Pettorossi VE, DiRocco C, Caldarelli M et al (1978) Influences of phasic changes in systemic blood pressure on intracranial pressure. Eur Neurol 17:216–225
Raksin PB, Alperin N, Sivaramakrishnan A et al (2003) Noninvasive intracranial compliance and pressure based on dynamic magnetic resonance imaging of blood flow and cerebrospinal fluid flow: review of principles, implementation, and other noninvasive approaches. Neurosurg Focus 14:1–8
Rutecki P (1990) Anatomical, physiological, and theoretical basis for the antiepileptic effect of vagus nerve stimulation. Epilepsia 31:S1–S6
Salinsky MC, Burchiel KJ (1993) Vagus nerve stimulation has no effect on awake EEG rhythms in humans. Epilepsia 34:299–304
Upton ARM (1992) Editorial. Pacing Clin Electrophysiol 15:1543–1544
Wallis DE, Littman WJ, Scanlon PJ et al (1987) The effects of elevated intracranial pressure on the canine electrocardiogram. J Electrocardiol 20:154–161
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Tubbs, R.S., Wellons, J.C., Blount, J.P. et al. Left-sided vagus nerve stimulation decreases intracranial pressure without resultant bradycardia in the pig: a potential therapeutic modality for humans. Childs Nerv Syst 20, 309–312 (2004). https://doi.org/10.1007/s00381-004-0947-x
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DOI: https://doi.org/10.1007/s00381-004-0947-x