OBJECTIVE: To evaluate the association between global cerebral blood flow and different cerebral perfusion pressure ranges in severe head injury. DESIGN: A retrospective study SETTING: Neurosurgical and trauma patients in an intensive care unit in a regional hospital. PATIENTS AND PARTICIPANTS: Out of a series of 237 consecutive patients with severe head injuries (GCS<or=8), 162 were submitted to ICP monitoring and 89 of them underwent 180 xenon-CT studies and cerebral perfusion pressure (CPP) measurement. The xenon-CT studies did not include any unsalvageable patients nor any mistakenly diagnosed as severe on entry. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Most (95.6%) of xenon-CT studies were obtained with CPP values within the 50-90 mmHg range. Perfusion data were grouped according to CPP values: (1) below 50 mmHg, (2) 50-60 mmHg, (3) 60-70 mmHg, (4) above 70 mmHg. Global cerebral blood flow did not differ among the groups (p=0.49). No differences in physiological variables were found among the CPP groups, except for intracranial pressure, higher in the group with CPP below 50 mmHg, and mean arterial pressure, higher in the CPP above 70 mmHg group (p<0.0001). No differences were found for cerebral metabolic rate of oxygen and lactate. CONCLUSIONS: There was little correlation between CPP values and global cerebral blood flow levels in our selected patients, probably because pressure autoregulation was preserved. Global metabolism measurements were constant within the groups, suggesting that in patients with controlled physiological variables an interplay between cerebral blood flow and metabolism might be more relevant than the relationship between CPP and cerebral blood flow.
OBJECTIVE: To evaluate the association between global cerebral blood flow and different cerebral perfusion pressure ranges in severe head injury. DESIGN: A retrospective study SETTING: Neurosurgical and traumapatients in an intensive care unit in a regional hospital. PATIENTS AND PARTICIPANTS: Out of a series of 237 consecutive patients with severe head injuries (GCS<or=8), 162 were submitted to ICP monitoring and 89 of them underwent 180 xenon-CT studies and cerebral perfusion pressure (CPP) measurement. The xenon-CT studies did not include any unsalvageable patients nor any mistakenly diagnosed as severe on entry. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Most (95.6%) of xenon-CT studies were obtained with CPP values within the 50-90 mmHg range. Perfusion data were grouped according to CPP values: (1) below 50 mmHg, (2) 50-60 mmHg, (3) 60-70 mmHg, (4) above 70 mmHg. Global cerebral blood flow did not differ among the groups (p=0.49). No differences in physiological variables were found among the CPP groups, except for intracranial pressure, higher in the group with CPP below 50 mmHg, and mean arterial pressure, higher in the CPP above 70 mmHg group (p<0.0001). No differences were found for cerebral metabolic rate of oxygen and lactate. CONCLUSIONS: There was little correlation between CPP values and global cerebral blood flow levels in our selected patients, probably because pressure autoregulation was preserved. Global metabolism measurements were constant within the groups, suggesting that in patients with controlled physiological variables an interplay between cerebral blood flow and metabolism might be more relevant than the relationship between CPP and cerebral blood flow.
Authors: Michael N Diringer; Tom O Videen; Kent Yundt; Allyson R Zazulia; Venkatesh Aiyagari; Ralph G Dacey; Robert L Grubb; William J Powers Journal: J Neurosurg Date: 2002-01 Impact factor: 5.115
Authors: Jonathan P Coles; Tim D Fryer; Piotr Smielewski; Doris A Chatfield; Luzius A Steiner; Andrew J Johnston; Stephen P M J Downey; Guy B Williams; Franklin Aigbirhio; Peter J Hutchinson; Kenneth Rice; T Adrian Carpenter; John C Clark; John D Pickard; David K Menon Journal: J Cereb Blood Flow Metab Date: 2004-02 Impact factor: 6.200
Authors: Jonathan P Coles; Tim D Fryer; Peter Smielewski; Kenneth Rice; John C Clark; John D Pickard; David K Menon Journal: J Cereb Blood Flow Metab Date: 2004-02 Impact factor: 6.200
Authors: Luzius A Steiner; Marek Czosnyka; Stefan K Piechnik; Piotr Smielewski; Doris Chatfield; David K Menon; John D Pickard Journal: Crit Care Med Date: 2002-04 Impact factor: 7.598
Authors: A P Carlson; A M Brown; E Zager; K Uchino; M P Marks; C Robertson; G P Sinson; A Marmarou; H Yonas Journal: AJNR Am J Neuroradiol Date: 2011-06-23 Impact factor: 3.825
Authors: Amanjyot Singh Sainbhi; Alwyn Gomez; Logan Froese; Trevor Slack; Carleen Batson; Kevin Y Stein; Dean M Cordingley; Arsalan Alizadeh; Frederick A Zeiler Journal: Front Neurol Date: 2022-04-26 Impact factor: 4.086
Authors: Massimo Antonelli; Elie Azoulay; Marc Bonten; Jean Chastre; Giuseppe Citerio; Giorgio Conti; Daniel De Backer; François Lemaire; Herwig Gerlach; Johan Groeneveld; Goran Hedenstierna; Duncan Macrae; Jordi Mancebo; Salvatore M Maggiore; Alexandre Mebazaa; Philipp Metnitz; Jerôme Pugin; Jan Wernerman; Haibo Zhang Journal: Intensive Care Med Date: 2008-01-04 Impact factor: 17.440