Showing papers by "Hebron University published in 1998"
01 Jun 1998
60 citations
TL;DR: The aim in this study was to analyze the ICP evolution pattern in the different groups of lesions of this classification and present the results of a prospective study in 94 patients with severe head injury, in whom ICP was monitored for at least 6 hours.
Abstract: Intracranial hypertension (ICH) is a frequent finding in patients with a severe head injury. High intracranial pressure (ICP) has been associated with certain computerized tomography (CT) abnormalities. The classification proposed by Marshall et al. based on CT scan findings, uses the status of the mesencephalic cisterns, the degree of midline shift, and the presence or absence of focal lesions to categorize the patients into different prognostic groups. Our aim in this study was to analyze the ICP evolution pattern in the different groups of lesions of this classification.
46 citations
TL;DR: The data do not support the premise that increasing cerebral perfusion pressure by inducing arterial hypertension is beneficial in those patients with a diffuse brain swelling in whom autoregulation is impaired or abolished.
Abstract: The present study was undertaken to elucidate the status of autoregulation and CO2-reactivity soon after injury in patients with a post-traumatic diffuse bilateral brain swelling. A prospective study was carried out in 31 consecutively admitted patients with a severe head injury and a Diffuse Brain Injury type III, following the definition stated by the Traumatic Coma Data Bank classification. To evaluate CO2-reactivity, AVDO2 was measured before and after ventilator manipulations. Assuming a constant CMRO2 during the test, changes in 1/AVDO2 reflect changes in CBF. Patients with changes in estimated CBF below or equal to 1% were included in the impaired/abolished CO2-reactivity group. To test autoregulation, hypertension was induced using phenylephrine. Arterial and jugular blood samples were taken to calculate AVDO2 before and after a steady state of MABP was obtained. Cerebrovascular response to CO2 was globally preserved in all but two cases (6.5%). In contrast, autoregulation was globally preserved in 10 (32.3%) and impaired/abolished in 21 cases (67.7%). Our data do not support the premise that increasing cerebral perfusion pressure by inducing arterial hypertension is beneficial in those patients with a diffuse brain swelling in whom autoregulation is impaired or abolished. Clinical implications for treatment are discussed.
40 citations
TL;DR: Monitoring of AVDO2 or other haemometabolic variables should be mandatory when sustained HV is used in the management of head injury patients, as it showed that HV was very effective in lowering ICP.
Abstract: Hyperventilation (HV) is routinely used in the management of increased intracranial pressure (ICP) in severe head injury. However, this treatment continues to be controversial because it has been reported that long-lasting reduced cerebral blood flow (CBF) due to profound sustained hypocapnia may contribute to the development or deterioration of ischemic lesions. Our goal in this study was to analyze the effects of sustained hyperventilation on cerebral hemodynamics (CBF, ICP) and metabolism (arterio jugular differences of lactates = AVDL). Co2-reactivity and CBF was estimated using AVDO2 (arteriojugular differences of oxygen content). Global cerebral ischemia and increased anaerobic metabolism were considered according to AVDO2 and AVDL respectively. Thirty-three patients with severe and moderate head injury and increased ICP were included. Within 72 hours after accident, patients were hyperventilated for a period of 4 hours. During this time jugular oxygen saturation (SjO2), arterial oxygen saturation (SaO2), ICP, mean arterial blood pressure (MABP), AVDO2 and AVDL were recorded.
39 citations
TL;DR: The data suggests that in patients with preserved CAR, potent opioids could cause greater increases of ICP, probably due to activation of the vasodilatadory cascade.
Abstract: Despite opioids are routinely used for analgesia in head injured patients, the effects of such drugs on ICP and cerebral hemodynamics remain controversial. Cerebrovascular autoregulation (CAR) could be an important factor in the ICP increases reported after opiod administration. In order to describe the effects on intracranial pressure of fentanyl and correlated such efects with autoregulation status, we studied 30 consecutive severe head injury patients who received fentanyl (2 μg/kg) intravenously over one minute. Prior to study, CAR was assessed. Monitoring included MAP, HR, SaO2, ETCO2, SjO2 and ICP. Changes in cerebral blood flow (CBF) were estimated from relative changes in AVDO2. Patients mean GCS was 5.7 ± 1.7 (mean ± STD) and mean ICP on admission was 23.8 ± 16.3 mmHg. Fentanyl caused significant increases in ICP and decreases in MAP and CPP, but CBF remained unchanged when estimated by AVDO2. In patients with preserved CAR (34.5%), opiod-induced ICP increase was greater (but not statistically significant) than in those with impaired CAR (65.5%). We conclude than fentanyl moderately increased ICP and decreased MAP and CPP. Our data suggests that in patients with preserved CAR, potent opioids could cause greater increases of ICP, probably due to activation of the vasodilatadory cascade.
22 citations