Effect of experimental brain injury on blood pressure, cerebral sinus pressure, cerebral venous oxygen tension, respiration, and acid-base balance

Abstract

✓ Changes in the blood pressure, cerebral sinus pressure, cerebral venous oxygen tension, acid-base balance, respiratory frequency, and respiratory minute volume were studied in the rabbit after a lethal cold injury to the brain. About half of the animals responded to the injury with a quick rise in cerebral sinus pressure and in its relation to blood pressure (CSP/BP); in the other half, cerebral sinus pressure and the CSP/BP ratio rose more slowly. Changes in the CSP/BP ratio correlated well with criteria for changes in respiratory performance. The changes in cerebral venous oxygen tension were reasonably uniform: a dip during freezing, an overshoot to a mean of 1.6 times the original level (about 30 mm Hg) immediately after injury, a gradual return to the pretraumatic level, and then a drop to lower levels. The brain injury led to a respiratory alkalosis that became more pronounced the longer the animals lived. Considered with CSP/BP ratio, respiratory reaction to the brain injury may provide an early and accurate prognosis. The fact that at the time of death the cerebral perfusion pressure was still within a range believed safe for the brain shows that an actual brain injury, in addition to raised intracranial pressure, is important in such experiments and emphasizes the inappropriateness of comparing levels of intracranial pressure raised by a variety of methods.

Cerebrospinal fluid enzymes in acute brain injury. 1. Dynamics of changes in CSF enzyme activity after acute experimental brain injury.

“…Kaste and Troupp (1972) produced a lethal cold lesion in rabbits and found that, in about half the animals, the injury resulted in a quick rise in cerebral sinus pressure and in its relation to the blood pressure, while in the others the cerebral sinus pressure and the ratio to the blood pressure rose more slowly.…”

Cerebrospinal fluid enzymes in acute brain injury. 1. Dynamics of changes in CSF enzyme activity after acute experimental brain injury.

“…Kaste and Troupp (1972) produced a lethal cold lesion in rabbits and found that, in about half the animals, the injury resulted in a quick rise in cerebral sinus pressure and in its relation to the blood pressure, while in the others the cerebral sinus pressure and the ratio to the blood pressure rose more slowly.…”

Effects of arterial hypoxaemia, hypercapnia, and changes in cerebral perfusion pressure on mean cerebrospinal fluid and sagittal sinus pressure

“…Later, Adolph et al (1967) demonstrated in an experimental study, where the effects of right atrial and left ventricular cardiac events were dissociated, that., depending on systemic haemodynamic conditions, CSF pressm'e waves are either venous or arterial in type. 1966, Guthrie et al 1970, Sahar et al 1970, Lowell et al 1971, Kaste et M. 1972, no simultaneous recordings of cerebrospinal pressure waves and cerebral venous pressure variations under physiological conditions were reported in previous neurosurgieal and physiological literature. 1964, Langfitt eta].…”

Prognosis for Patients with Severe Brain Injuries

“…One can, of course, speculate about the reasons for the correlation of these findings with the fate of the patient; perhaps these violent reactions denote a brain injury so severe as to preclude recovery. It has been shown experimentally that the animals hyperventilating most after a standardized cold injury of the brain survive the longest (Kaste, 1970); the same may apply to man, but the experimental injury referred to was designed to be lethal, and the quality of survival did not enter into it.…”

Cerebrospinal fluid enzymes in acute brain injury. 1. Dynamics of changes in CSF enzyme activity after acute experimental brain injury.

“…Kaste and Troupp (1972) produced a lethal cold lesion in rabbits and found that, in about half the animals, the injury resulted in a quick rise in cerebral sinus pressure and in its relation to the blood pressure, while in the others the cerebral sinus pressure and the ratio to the blood pressure rose more slowly.…”

Effects of arterial hypoxaemia, hypercapnia, and changes in cerebral perfusion pressure on mean cerebrospinal fluid and sagittal sinus pressure

“…Later, Adolph et al (1967) demonstrated in an experimental study, where the effects of right atrial and left ventricular cardiac events were dissociated, that., depending on systemic haemodynamic conditions, CSF pressm'e waves are either venous or arterial in type. 1966, Guthrie et al 1970, Sahar et al 1970, Lowell et al 1971, Kaste et M. 1972, no simultaneous recordings of cerebrospinal pressure waves and cerebral venous pressure variations under physiological conditions were reported in previous neurosurgieal and physiological literature. 1964, Langfitt eta].…”

Prognosis for Patients with Severe Brain Injuries

“…One can, of course, speculate about the reasons for the correlation of these findings with the fate of the patient; perhaps these violent reactions denote a brain injury so severe as to preclude recovery. It has been shown experimentally that the animals hyperventilating most after a standardized cold injury of the brain survive the longest (Kaste, 1970); the same may apply to man, but the experimental injury referred to was designed to be lethal, and the quality of survival did not enter into it.…”

Cerebrospinal fluid enzymes in acute brain injury. 1. Dynamics of changes in CSF enzyme activity after acute experimental brain injury.

“…Kaste and Troupp (1972) produced a lethal cold lesion in rabbits and found that, in about half the animals, the injury resulted in a quick rise in cerebral sinus pressure and in its relation to the blood pressure, while in the others the cerebral sinus pressure and the ratio to the blood pressure rose more slowly.…”

Effects of arterial hypoxaemia, hypercapnia, and changes in cerebral perfusion pressure on mean cerebrospinal fluid and sagittal sinus pressure

“…Later, Adolph et al (1967) demonstrated in an experimental study, where the effects of right atrial and left ventricular cardiac events were dissociated, that., depending on systemic haemodynamic conditions, CSF pressm'e waves are either venous or arterial in type. 1966, Guthrie et al 1970, Sahar et al 1970, Lowell et al 1971, Kaste et M. 1972, no simultaneous recordings of cerebrospinal pressure waves and cerebral venous pressure variations under physiological conditions were reported in previous neurosurgieal and physiological literature. 1964, Langfitt eta].…”

Prognosis for Patients with Severe Brain Injuries

“…One can, of course, speculate about the reasons for the correlation of these findings with the fate of the patient; perhaps these violent reactions denote a brain injury so severe as to preclude recovery. It has been shown experimentally that the animals hyperventilating most after a standardized cold injury of the brain survive the longest (Kaste, 1970); the same may apply to man, but the experimental injury referred to was designed to be lethal, and the quality of survival did not enter into it.…”