Influence of an increased intracranial pressure on cerebral and systemic haemodynamics during endoscopic neurosurgery: an animal model

Abstract

Upon complete suppression of the CPP, an obvious hypertension developed, often together with tachycardia, but no severe bradycardia. At high ICP levels, we observed an important translocation of irrigation fluid to the vascular space. Fatality was not caused by ischaemia or arrhythmia but due to pulmonary oedema.

Anaesthetic complications in pigs undergoing MRI guided convection enhanced drug delivery to the brain: a case series

“…Tachycardia has been demonstrated in response to raised intracranial pressure in a number of neurosurgical procedures, and the bradycardia of Cushing's triad is known to be a late-stage phenomenon (Kalmar et al 2009). However, a tachycardic response and compensatory hypertension appears unlikely after such a localised infusion.…”

Anaesthetic Management of Patients Undergoing Intraventricular Neuro-Endoscopic Procedures

“…The principal reasons for induced intracranial hypertension are high flow rinsing (used to improve visibility during bleeding or to maintain access in collapsing ventricles ) and obstruction of the outflow channel by tissue debris , blood clots or kinking of outflow tubes. These increases in ICP must be detected as soon as possible to prevent severe complications such as cardiovascular instability (Fabregas et al, 2002, Handler et al, 1994 , herniation syndromes, retinal bleeding (Boogaarts et al, 2008 ;Hoving et al, 2009) and excessive fluid resorption (Kalmar et al, 2009). Aside from these unambiguous complications animal research showed that awakening without apparent neurological deficit does not preclude histological damage (Kalmar et al 2009).…”

“…It is very conceivable that the differences in these observations are a result of variations in surgical practice. Additionally, direct pressure on certain anatomical regions seems mainly to provoke bradycardia (Baykan et al, 2005), while isolated intracranial hypertension seems rather to induce tachycardia (Kalmar et al, 2009). Al-Dawlatly suggests that the possible absence of tachycardia found in many studies may be due to the protocol that allows the irrigation fluid to vent out during the procedure without noticeable accumulation in the third ventricle.…”

“…The haemodynamic reflex induced by isolated intracranial hypertension always consisted of hypertension, and the absence of bradycardia did not even exclude a CPP of zero. In many cases, a severe tachycardia is the only and very distinct constituent of the induced Cushing reflex (Kalmar 2009). Moreover, in this animal model, significant rinsing fluid resorption was observed at high rinsing pressures, resulting in considerable decrease in hematocrit.…”

Pressure monitoring during neuroendoscopy: new insights

“…Excessive increases in ICP should be avoided, since intracranial hypertension can lead to cardiovascular complications, 11 12 herniation syndromes, retinal bleeding, 8 10 and excessive fluid resorption. 13 Transcranial Doppler ultrasonography measurements during rinsing procedures have shown severe decreases in cerebral perfusion without systemic haemodynamic warning signs. 14 ICP monitoring is thus important, but the optimal location of monitoring is controversial.…”