Urotensinergic system genes in experimental subarachnoid hemorrhage.

OBJECTIVE: Cerebral vasospasm, one of the main complications of subarachnoid hemorrhage (SAH), is characterized by arterial constriction and mainly occurs from day 4 until the second week after the event. Urotensin-II (U-II) has been described as the most potent vasoconstrictor peptide in mammals. An analysis is made of the serum U-II concentrations and mRNA expression levels of U-II, urotensin related peptide (URP) and urotensin receptor (UT) genes in an experimental murine model of SAH. DESIGN: An experimental study was carried out. SETTING: Experimental operating room of the Biomedicine Institute of Seville (IBiS), Virgen del Rocío University Hospital (Seville, Spain). PARTICIPANTS: 96 Wistar rats: 74 SAH and 22 sham intervention animals. INTERVENTIONS: Day 1: blood sampling, followed by the percutaneous injection of 100µl saline (sham) or blood (SAH) into the subarachnoid space. Day 5: blood sampling, followed by sacrifice of the animals. MAIN VARIABLES OF INTEREST: Weight, early mortality, serum U-II levels, mRNA values for U-II, URP and UT. RESULTS: Serum U-II levels increased in the SAH group from day 1 (0.62pg/mL [IQR 0.36-1.08]) to day 5 (0.74pg/mL [IQR 0.39-1.43]) (p<0.05), though not in the sham group (0.56pg/mL [IQR 0.06-0.83] day 1; 0.37pg/mL [IQR 0.23-0.62] day 5; p=0.959). Between-group differences were found on day 5 (p<0.05). The ROC analysis showed that the day 5 serum U-II levels (AUC=0.691), URP mRNA (AUC=0.706) and UT mRNA (AUC=0.713) could discriminate between sham and SAH rats. The normal serum U-II concentration range in rats was 0.56pg/mL (IQR 0.06-0.83). CONCLUSION: The urotensinergic system is upregulated on day 5 in an experimental model of SAH.

[An experimental model of mass-type brain damage in the rat: expression of brain damage based on neurospecific enolase and protein S100B]. / Modelo experimental de lesión cerebral tipo masa en rata: expresión del daño cerebral mediante enolasa neuroespecífica y proteína S100B.

OBJECTIVE: To determine whether a model of transient mass-type brain damage (MTBD) in the rat produces early release of neurospecific enolase (NSE) and protein S100B in peripheral blood, as an expression of the induced brain injury. DESIGN: An experimental study with a control group. SETTING: Experimental operating room of the Institute of Biomedicine (IBiS) of Virgen del Rocío University Hospital (Seville, Spain). PARTICIPANTS: Fourteen adult Wistar rats. INTERVENTIONS: Blood was sampled at baseline, followed by: MTBD group, a trephine perforation was used to insert and inflate the balloon of a catheter at a rate of 500 µl/20 sec, followed by 4 blood extractions every 20 min. Control group, the same procedure as before was carried out, though without trephine perforation. PRIMARY STUDY VARIABLES: Weight, early mortality, serum NSE and S100B concentration. RESULTS: Differences in NSE and S100B concentration were observed over time within the MTBD group (P<.001), though not so in the control group. With the exception of the baseline determination, differences were observed between the two groups in terms of the mean NSE and S100B values. Following MTBD, NSE and S100B progressively increased at all measurement timepoints, with r=0.765; P=.001 and r=0.628; P=.001, respectively. In contrast, the control group showed no such correlation for either biomarker. CONCLUSIONS: Serum NSE and S100B concentrations offer an early indication of brain injury affecting the gray and white matter in an experimental model of mass-type MTBD in the rat.

Ultrasonografía doppler transcraneal urgente: utilidad predictiva del vasoespasmo sintomático en la hemorragia subaracnoidea espontánea en pacientes con buena situación neurológica / Emergency transcranial doppler ultrasound: predictive value for the development of symptomatic vasospasm in spontaneous subarachnoid hemorrhage in patients in good neurological condition

Objetivo: Establecer el valor predictivo, para desarrollar deterioro neurológico tardío de origen isquémico (DNI), de un estudio doppler transcraneal (DTC) en pacientes con hemorragia subaracnoidea espontánea (HSA) en buena situación neurológica. Diseño: Estudio descriptivo-observacional desarrollado durante 3 años. Ámbito: Cuidados Críticos y Urgencias. Pacientes: Se incluyeron de forma consecutiva aquellos pacientes con HSA en buena situación neurológica (Hunt-Hess I-III). Variables de Interés: DNI (disminución en 2 puntos del GCS o déficit focal), velocidad media (VM) en arterias cerebrales medias, índice de Lindegaard (IL). Se consideró patrón sonográfico de vasoespasmo (PSV) cuando la VM fue>120cm/s y existía un IL>3. Resultados: La media de edad de los 122 pacientes fue de 54,1±13,7 años. El 57,3% eran mujeres. Se detectaron 24 pacientes con PSV (19,7%) encontrándose VM elevadas en 38 pacientes (31,1%). 21 pacientes desarrollaron DNI (VM 183+/-49cm/s), todos presentaron PSV. En los pacientes con DNI se detectó un aumento de VM de 22+/-5cm/s/24h durante los 3 primeros días. Al comparar aquellos pacientes que no presentaron VM elevadas (85 pacientes/VM 67+/-16,6cm/s) con respecto a los que desarrollaron DNI encontramos diferencias en las VM (p<0,001) y en el ΔVM/24h (8,30+/-4,5cm/s Vs 22+/-5cm/s) durante los 3 primeros días (p=0,009). Mediante curvas ROC, se fijó que el ΔVM/día de 21cm/s (p<0,001), era el que mejor predecía el DNI. Conclusión: Durante los 3 primeros días un incremento en la VM de 21cm/s/24h se asoció con el desarrollo de vasoespamo sintomático. El DTC es una herramienta útil para la detección de aquellos pacientes con HSA en riesgo de desarrollar DNI (AU)

Purpose: To examine the predictive value of an early transcranial Doppler ultrasound (TCD) study performed in the emergency department in patients with spontaneous subarachoniod hemorrhage (SAH) in good neurological condition, in order to know which patients are at high risk of developing delayed cerebral ischemia (DCI). Design: A descriptive observational study was carried out involving a period of 3 years. Setting: Critical Care and Emergency Department. Patients: The study consecutively included patients with SAH of grade I-III on the Hunt and Hess scale. Variables of Interest: DCI (decrease of 2 points in GCS or focal deficit), Mean Velocity (MV) of middle cerebral arteries (MCA), Lindegaard Index (IL). Sonographic vasospasm pattern (SVP) was considered if MCA-MV>120cm/sc and IL>3. Results: The mean age of the 122 patients was 54.1±13.7 years; 57.3% were women. SVP was detected in 24 patients (19.7%), although high velocities patterns (HVP) were present in 38 patients (31.1%). DCI developed in 21 patients (MV183+/-49cm/sc), all with previous SVP. In this group MV increased 22+/-5cm/sc/day during the first 3 days. The group without HVP (84 patients/MV of 67+/-16.6cm/sc), compared with DCI group, showed differences in highest MV (p<0.001), and also ΔMV/day (8.30+/-4,5cm/sc Vs 22+/-5cm/sc) during the first 3 days (p=0.009). In our series, ROC analysis selected the best cut-off value for ΔMV/day as 21cm/sc (p<0.001). Conclusion: During the first 3 days, an increase of 21cm/s/24h in MCA-MV was associated with the development of symptomatic vasospasm. TCD is a useful tool for the early detection of patients at risk of DCI after SAH (AU=

A new percutaneous model of Subarachnoid Haemorrhage in rats.

OBJECTIVE: Describe the results obtained with a new percutaneous, intracisternal model of Subarachnoid Haemorrhage (SAH) in Wistar rats by a single injection of non-heparinised, autologous blood. METHODS: Once anaesthetized the rat was fixed prone in a stereotaxic frame. After identifying the projection of the occipital bone, the needle of the stereotaxic frame aspirated towards the foramen magnum until it punctured through the atlanto-occipital membrane and obtained cerebrospinal fluid. Autologous blood (100 µl) was withdrawn from the tail and injected intracisternally. This procedure was repeated in the sham group, injecting 100 µl of isotonic saline. On the fifth day post-intervention, the rats were anaesthetized and the brain was exposed. After a lethal injection of ketamine the brain was explanted and fixed in paraformaldehyde. Gross and microscopic inspection of the slices revealed the existence or non-existence of pathological findings. RESULTS: A total of 26 rats were operated on (13 in the SAH group/13 in the sham group). The average time between obtaining the blood and the start of the intracisternal injection was 10 (±1.2)s. The mortality rate was 16.12%. Intra- and extraparenchymal ischemic-haemorrhagic lesions were found in three animals (23.07%)--all from the SAH group--with ischemic neuronal cell injury detected in two of the three. CONCLUSIONS: The new murine model of SAH is easy to perform, with low mortality, minimally invasive, which makes it interesting for future studies on vasospasm-related delayed SAH complications.

La microdiálisis cerebral en el ámbito clínico actual / Cerebral microdialysis in the current clinical setting

La microdiálisis cerebral, introducida en estudios experimentales hace unos 40 años, ha sido empleada en la clínica desde 1992 para la monitorización neuroquímica de pacientes en unidades de cuidados intensivos. Los principios en los que se basa esta técnica se encuentran íntimamente ligados al metabolismo cerebral. El estudio de los metabolitos detectados en el intersticio tisular cerebral, a través de la membrana semipermeable de la que dispone el dispositivo, permite estimar la situación de las distintas rutas metabólicas fisiológicas cerebrales, analizando las modificaciones que se producen cuando estas tornan hacia rutas menos eficientes desde el punto de vista energético y detectando productos de desecho secundarios a la lesión tisular. A pesar de sus limitaciones actuales, esta técnica aporta información relevante para la investigación y el abordaje clínico de los pacientes neurocríticos (AU)

Cerebral microdialysis, introduced in experimental studies 40 years ago, has been used clinically since 1992 for the neurochemical monitoring of patients in intensive care. The principles underlying this technique are closely related to brain metabolism. The study of the metabolites detected at brain interstitial tissue level, through the semipermeable membrane of the device, allows us to assess different physiological pathways in the brain, analyzing the changes that occur when they become less efficient in terms of energy, and also detecting waste products secondary to tissue damage. Despite its current limitations, this technique provides relevant information for research and the clinical management of critical neurological patients (AU)

[Emergency transcranial doppler ultrasound: predictive value for the development of symptomatic vasospasm in spontaneous subarachnoid hemorrhage in patients in good neurological condition]. / Ultrasonografía doppler transcraneal urgente: utilidad predictiva del vasoespasmo sintomático en la hemorragia subaracnoidea espontánea en pacientes con buena situación neurológica.

PURPOSE: To examine the predictive value of an early transcranial Doppler ultrasound (TCD) study performed in the emergency department in patients with spontaneous subarachoniod hemorrhage (SAH) in good neurological condition, in order to know which patients are at high risk of developing delayed cerebral ischemia (DCI). DESIGN: A descriptive observational study was carried out involving a period of 3 years. SETTING: Critical Care and Emergency Department. PATIENTS: The study consecutively included patients with SAH of grade I-III on the Hunt and Hess scale. VARIABLES OF INTEREST: DCI (decrease of 2 points in GCS or focal deficit), Mean Velocity (MV) of middle cerebral arteries (MCA), Lindegaard Index (IL). Sonographic vasospasm pattern (SVP) was considered if MCA-MV>120cm/sc and IL>3. RESULTS: The mean age of the 122 patients was 54.1±13.7 years; 57.3% were women. SVP was detected in 24 patients (19.7%), although high velocities patterns (HVP) were present in 38 patients (31.1%). DCI developed in 21 patients (MV183+/-49cm/sc), all with previous SVP. In this group MV increased 22+/-5cm/sc/day during the first 3 days. The group without HVP (84 patients/MV of 67+/-16.6cm/sc), compared with DCI group, showed differences in highest MV (p<0.001), and also ΔMV/day (8.30+/-4,5cm/sc Vs 22+/-5cm/sc) during the first 3 days (p=0.009). In our series, ROC analysis selected the best cut-off value for ΔMV/day as 21cm/sc (p<0.001). CONCLUSION: During the first 3 days, an increase of 21cm/s/24h in MCA-MV was associated with the development of symptomatic vasospasm. TCD is a useful tool for the early detection of patients at risk of DCI after SAH.

[Cerebral microdialysis in the current clinical setting]. / La microdiálisis cerebral en el ámbito clínico actual.

Cerebral microdialysis, introduced in experimental studies 40 years ago, has been used clinically since 1992 for the neurochemical monitoring of patients in intensive care. The principles underlying this technique are closely related to brain metabolism. The study of the metabolites detected at brain interstitial tissue level, through the semipermeable membrane of the device, allows us to assess different physiological pathways in the brain, analyzing the changes that occur when they become less efficient in terms of energy, and also detecting waste products secondary to tissue damage. Despite its current limitations, this technique provides relevant information for research and the clinical management of critical neurological patients.

Accuracy of the S100ß protein as a marker of brain damage in traumatic brain injury.

INTRODUCTION: This study tested the hypothesis that S100ß is a useful screening tool for detecting intracranial lesion (IL) in patients with a normal level of consciousness after traumatic brain injury (TBI). METHODS: One hundred and forty-three post-TBI patients without a decrease in consciousness (GCS = 15) and with at least one neurological symptom (e.g. transitory loss of consciousness, amnesia, headache, dizziness or vomiting) were prospectively included. A blood sample was drawn at 6-hours post-TBI. A routine CT scan was obtained within 24 hours post-injury. Diagnostic properties of S100ß for IL prediction in CT scan findings were tested using ROC-analysis. RESULTS: A total of 15 patients (10.5%) had IL. Serum levels were significantly higher in these patients. Significant differences were found between S100ß levels and CT scan findings (p = 0.007). ROC-analysis showed that S100ß is a useful tool for detecting the presence of IL in CT scans (p = 0.007). In this series, the best cut-off for S100ß is 0.130 µg L(-1), with 100% sensitivity and 32.81% specificity. CONCLUSION: Within the first 6 hours post-TBI, serum S100ß seems to be an effective biochemical indicator of IL in patients without a decrease in consciousness. These results indicate that higher S100ß cut-off values substantially improve the clinical relevance of this protein.

[Improving the outcomes in spontaneous subarachnoid haemorrhage: the EHSA project]. / Mejora de los resultados en la hemorragia subaracnoidea espontánea: proyecto EHSA.

AIM: To investigate our clinical practices with the aim of identifying opportunities to improve the medico-surgical management of spontaneous subarachnoid haemorrhages (SAH). PATIENTS AND METHODS A prospective, longitudinal cohort study was conducted of the cases of SAH attended consecutively in the critical care and emergency services in 29 public hospitals in Andalusia over a period of 20 months, between the years 2000 and 2002. SAH were considered to be acute haemorrhagic cerebrovascular accidents diagnosed as such by imaging. Results at 12 months and care management (medical and surgical therapy, diagnostic techniques, care times and specific neurological complications) were analysed and the latter was then compared with the clinical practices that scientific evidence has proved to be the most useful. Deaths due to rebleeding in patients with no arteriographic study or without exclusion of the aneurysm were catalogued as potentially avoidable deaths. RESULTS: A total of 506 SAH were included. During the follow-up 5% of the sample were lost. In all 155 patients died. The non-modifiable independent risk variables for mortality were: age, being male, history of arterial hypertension, coma on arrival at the hospital and hydrocephalus. The independent risk variables for death that can be influenced were: absence of urgent analgesic, no arteriographic diagnosis, appearance of ischaemic neurological impairment and rebleeding. Twenty per cent of the overall mortality could be considered potentially avoidable. CONCLUSIONS: Although fatality is mostly dependent on variables that cannot be influenced (sex, age, history, clinical severity and hydrocephalus), 20% of deaths are associated to modifiable factors.

Mejora de los resultados en la hemorragia subaracnoidea espontánea: proyecto EHSA / Improving the outcomes in spontaneous subarachnoid haemorrhage: The Ehsa project

Objetivo. Investigar nuestras prácticas clínicas, a fin de identificar oportunidades de mejora en el manejo medicoquirúrgicode las hemorragias subaracnoideas (HSA) espontáneas. Pacientes y métodos. Estudio de cohortes, longitudinal,prospectivo, de las HSA atendidas consecutivamente en los servicios de cuidados críticos y urgencias de 29 hospitales públicosde Andalucía durante 20 meses, de 2000 a 2002. Se consideraron HSA los accidentes cerebrovasculares hemorrágicosagudos con este diagnóstico tomográfico. Se analizaron los resultados a 12 meses y el manejo asistencial (terapéutica médicay quirúrgica, técnicas diagnósticas, tiempos asistenciales y complicaciones neurológicas específicas), comparándolo conlas prácticas clínicas que la evidencia científica ha demostrado de mayor utilidad. Se catalogaron como muertes potencialmenteevitables los óbitos por resangrado en pacientes sin estudio arteriográfico o sin exclusión del aneurisma. Resultados.Se incluyeron 506 HSA. Se perdió durante el seguimiento el 5% de la muestra. Fallecieron 155 enfermos. Las variables no modificablesde riesgo independiente para la mortalidad fueron: edad, género masculino, antecedente de hipertensión arterial,coma a la recepción hospitalaria e hidrocefalia. Las variables influenciables de riesgo independiente para fallecer resultaronser: ausencia de analgesia urgente, carencia de diagnóstico arteriográfico, aparición de deterioro neurológico isquémico yresangrado. El 20% de la mortalidad global podría considerarse potencialmente evitable. Conclusiones. Aunque la letalidades mayoritariamente dependiente de variables médicamente no influenciables (sexo, edad, antecedentes, gravedad clínica ehidrocefalia), los decesos, en un 20%, están asociados a factores modificables (AU)

Aim. To investigate our clinical practices with the aim of identifying opportunities to improve the medico-surgicalmanagement of spontaneous subarachnoid haemorrhages (SAH). Patients and methods. A prospective, longitudinal cohortstudy was conducted of the cases of SAH attended consecutively in the critical care and emergency services in 29 publichospitals in Andalusia over a period of 20 months, between the years 2000 and 2002. SAH were considered to be acutehaemorrhagic cerebrovascular accidents diagnosed as such by imaging. Results at 12 months and care management (medicaland surgical therapy, diagnostic techniques, care times and specific neurological complications) were analysed and the latterwas then compared with the clinical practices that scientific evidence has proved to be the most useful. Deaths due torebleeding in patients with no arteriographic study or without exclusion of the aneurysm were catalogued as potentiallyavoidable deaths. Results. A total of 506 SAH were included. During the follow-up 5% of the sample were lost. In all 155patients died. The non-modifiable independent risk variables for mortality were: age, being male, history of arterial hypertension,coma on arrival at the hospital and hydrocephalus. The independent risk variables for death that can be influenced were: absence of urgent analgesic, no arteriographic diagnosis, appearance of ischaemic neurological impairment and rebleeding. Twenty per cent of the overall mortality could be considered potentially avoidable. Conclusions. Although fatality is mostly dependent on variables that cannot be influenced (sex, age, history, clinical severity and hydrocephalus), 20% of deaths are associated to modifiable factors (AU)

Skull fracture, with or without clinical signs, in mTBI is an independent risk marker for neurosurgically relevant intracranial lesion: a cohort study.

PRIMARY OBJECTIVE: To explore the possibility of identifying skull fracture, with or without clinical signs, as a predictor of positive CT scans in mild traumatic brain injury (mTBI). RESEARCH DESIGN: Prospective cohort study, matched 1:1 for five potential confounding variables (age, sex, symptoms, mechanism of injury and extracranial trauma severity). METHODS AND PROCEDURES: The study was performed on patients with mTBI (Glasgow Coma Scale 15-14), with or without radiologically demonstrated skull fracture. The cohort with skull fracture included 155 patients selected from a sample of 5097 mTBI patients treated during 1998 at the Critical Care and Emergency Department of the Trauma Centre. The cohort without skull fracture was prospectively recruited from patients with mTBI treated in the same department from 2002-2005. MAIN OUTCOMES AND RESULTS: The percentage of patients with intracranial lesion (IL) was significantly higher in mTBI patients with skull fracture than in those without. The risk of requiring neurosurgery was 5-fold higher when skull fracture was present. Of mTBI patients with skull fracture and IL, 63.2% showed no clinical signs of bone injury. CONCLUSIONS: Skull fracture, with or without clinical signs, in mTBI patients is associated with an increased risk of neurosurgically-relevant intracranial lesion.

Monitorización de la presión tisular de oxígeno (PtiO2) en la hipoxia cerebral: aproximación diagnóstica y terapéutica / Monitoring of tissue oxygen pressure (PtiO2) in cerebral hypoxia: diagnostic and therapeutic approach

Una de las causas principales de lesión cerebral secundaria es la hipoxia cerebral, fundamentalmente de origen isquémico. No obstante, la oxigenación tisular cerebral depende de múltiples variables fisiológicas y la hipoxia cerebral puede ser originada por una alteración de cualquiera de ellas. Aunque han sido desarrollados varios métodos de monitorización continua de la oxigenación cerebral en pacientes neurocríticos, la medición directa y continua de la presión de oxígeno en el tejido cerebral (PtiO2) es una realidad en el manejo de pacientes neurocríticos desde los últimos años. Esta técnica destaca por su fiabilidad y valor de la información que proporciona. En el presente artículo se expone una revisión de los aspectos más relevantes de la monitorización de la PtiO2 y se propone un protocolo para su interpretación. Este algoritmo pretende facilitar la identificación de diferentes tipos de hipoxia cerebral y la correcta elección terapéutica en el complejo proceso de toma de decisiones en pacientes neurológicos críticos en riesgo de hipoxia cerebral

One of the main causes of secondary cerebral injury is cerebral hypoxia, basically of ischemic origin. However, cerebral tissue oxygenation depends on multiple physiological variables and cerebral hypoxia may be caused by an alteration of any one of them. Although several methods of continuous cerebral oxygenation monitoring of neurocritical patients have been developed, direct and continuous measurement of the oxygen pressure in the cerebral tissue (PtiO2) has been a reality in the handling of the neurocritical patients over recent years. This technique is highlighted by its reliability and value of the information that it provides. This present article presents a review of the most outstanding aspects of the PtiO2 monitoring and proposes a protocol for the interpretation of this monitoring technique. This algorithm attempts to facilitate the identification of the different types of different cerebral hypoxia and of the correct therapeutic choice in the complex decision making process in neurocritical patients at risk of cerebral hypoxia

[Monitoring of tissue oxygen pressure (PtiO2) in cerebral hypoxia: diagnostic and therapeutic approach]. / Monitorización de la presión tisular de oxígeno (PtiO2) en la hipoxia cerebral: aproximación diagnóstica y terapéutica.

One of the main causes of secondary cerebral injury is cerebral hypoxia, basically of ischemic origin. However, cerebral tissue oxygenation depends on multiple physiological variables and cerebral hypoxia may be caused by an alteration of any one of them. Although several methods of continuous cerebral oxygenation monitoring of neurocritical patients have been developed, direct and continuous measurement of the oxygen pressure in the cerebral tissue (PtiO2) has been a reality in the handling of the neurocritical patients over recent years. This technique is highlighted by its reliability and value of the information that it provides. This present article presents a review of the most outstanding aspects of the PtiO2 monitoring and proposes a protocol for the interpretation of this monitoring technique. This algorithm attempts to facilitate the identification of the different types of different cerebral hypoxia and of the correct therapeutic choice in the complex decision making process in neurocritical patients at risk of cerebral hypoxia.

[Evidence of occult systemic hypoperfussion in head injured patients. Preliminary study]. / Existencia de hipoperfusión oculta sistémica en el traumatismo craneoecefálico. Estudio preliminar

OBJECTIVES: To determine the correlation between blood lactic acid levels in the first 48 hours and outcome, in hemodynamically stable patients, with moderate or severe head injury (HI), and to investigate the risk factors associated with abnormal lactate levels. MATERIAL AND METHODS: A prospective observational study, in 210 adults patients with moderate or severe head injury. When the patients were hemodynamically stable, blood lactate concentrations were measured once on admission, twice daily during the first 2 days and once daily until lactate levels were normalized. The whole group 210 patients were divided into 2 groups. Group 1: (LA < 2.2 mmol/L) patients without occult hypoperfussion (OH), and group 2: (LA >or= 2.2 mmol/L) patients with OH. RESULTS: One hundred and fifteen patients (57.76%) were categorized as group 1, and 95 patients (45.24%) as group 2. In the univariate analysis of risk factors for blood lactate >or=2.2 mmol/L the following variables showed statistical significance: severity of the head injury measured by several scales [Glasgow Coma Scale (GCS), Injury Severity Score (ISS), Revised Trauma Score (RTS) and Acute Physiology and Chronic Health Evaluation (APACHE) II], arterial hypotension, hypoxemia, anaemia, hyperglucemia, hypothermia, a greater incidence of norepinephrine infusion, and the higher percentage of type II lesions in the head computerized tomography at admission showed in the group 1 (53.91% vs. 38.94%) (p<0.03). In the multiple logistic regression analysis only two variables were risk independently associated with elevated blood lactate concentration: APACHE II in the first 24 hours: OR 1.12 (95% IC 1.06--1.196; p<0.0001) and the first 48-hours total fluid infusion volumes: OR 1.09 (95% IC 1.021,16; p < 0.0001). The infection rate (63.2% vs 47.8%, p=0.026), and length of ICU stay [mediana (percentil 25--75)] [13.29 (7.11--21.22) days vs. 8.78 (4.40--16.72) days; p<0.018] were significantly higher in patients with blood lactate >or=2.2 mmol/L (group 2). Although, the percentage of intracranial hypertension and mortality was higher in the group 2, there was no significant difference. In the multivariate analysis, the increase of blood lactate concentration, was not independently associated as a risk factor with studied complications. CONCLUSIONS: The presence of OH in patients with moderate or severe head injury, with postres uscitation arterial pressure, according to present recommendations, is associated with a more severe head injury, showed by APACHE II and the total fluid infusion volumes in the first 48 hours. OH in head injury increases the infection rate and length of ICU stay.

Existencia de hipoperfusión oculta sistémica en el traumatismo craneoencefálico. Estudio preliminar / Evidence of occult systemic hypoperfussion in head injured patients. Preliminary study

Objetivos. Investigar en pacientes con traumatismo craneoencefálico grave y moderado (TCE), hemodinámicamente estables, la relación entre los valores arteriales de ácido láctico (AL) en las primeras 48 horas con la evolución y complicaciones del TCE, y conocer qué factores de riesgo se relacionan con valores anormales de AL. Material y métodos. Estudio observacional, prospectivo, de cohorte, de 210 pacientes adultos con TCE grave y moderado. Conseguida la estabilización hemodinámica del paciente, se realizó una determinación basal de AL, que se repitió cada 12 horas durante las primeras 48 horas y, posteriormente, cada 24 horas hasta la normalización de los valores de AL. Los pacientes se clasificaron en dos grupos: Grupo 1 (AL = 2,2 mmol/L) con HO. Resultados. 115 pacientes (57,76%) se catalogaron como grupo 1, y 95 pacientes (45,24%) como grupo 2. En el análisis univariante de los factores de riesgo para AL >= 2,2 mmol/L mostraron significación estadística todos los índices generales de gravedad del TCE [Glasgow Coma Scale (GCS), Injury Severity Score (ISS), Trauma Score Revisado (TSR) y Acute Physiology and Chronic Health Evaluation (APACHE) II], la hipotensión arterial, hipoxemia, anemia, hiper-glucemia, hipotermia y la mayor incidencia de administración de noradrenalina. Asimismo, en el grupo 1 se objetivó un mayor porcentaje en la TAC de ingreso de lesiones tipo II (53,91% vs. 38,94%) (p<0,03). En el análisis multivariante de regresión logística, sólo dos factores se asociaron de forma independiente a valores elevados de AL: APACHE II en las primeras 24 horas: OR 1,12 (IC 95% 1,06-1,196; p<0,0001) y volumen de líquidos total infundido en las primeras 48 horas: OR 1,09 (IC 95% 1,02-1,16; p<0,0001). El grupo 2 se asoció, con significación estadística, a una mayor tasa de infecciones(63,2% vs 47,8%, p=0,026), y al aumento de la estancia en UCI. [mediana (percentil 25-75)] [13,29 (7,11-21,22) días vs. 8,78 (4,40-16,72) días; p<0,018]. Aunque fue más alto el porcentaje de hipertensión intracraneal y mortalidad en el grupo 2, no se constató significación estadística. El aumento de AL, en el análisis multivariante, no se comportó como factor independiente de riesgo para las complicaciones estudiadas. Conclusiones. La existencia de HO en pacientes con TCE graves y moderados, con valores de presión arterial postreanimación según las recomendaciones actuales, se asocia a una mayor gravedad del TCE manifestada por el APACHE II y por el volumen de líquidos administrado en las primeras 48 horas. La HO en el TCE conlleva un aumento de la tasa de infecciones y de la estancia en UCI

Objectives. To determine the correlation between blood lactic acid levels in the first48 hours and outcome, in hemodynamically stable patients, with moderate or severe head injury (HI), and to investigate the risk factors associated with abnormal lactate levels. Material and methods. A prospective observational study, in 210 adults patients with moderate or severe head injury. When the patients were hemodynamically stable, blood lactate concentrations were measured once on admission, twice daily during the first 2 days and once daily until lactate levels were normalized. The whole group 210 patients were divided into 2 groups. Group 1: (LA = 2,2 mmol/L) patients with OH. Results. One hundred and fifteen patients (57,76%) were categorized as group 1, and 95 patients (45,24%) as group 2. In the univariate analysis of risk factors for blood lactate >= 2,2 mmol/L the following variables showed statistical significance: severity of the head injury measured by several scales [Glasgow Coma Scale (GCS), Injury Severity Score (ISS), Revised Trauma Score (RTS) and Acute Physiology and Chronic Health Evaluation (APACHE) II], arterial hypotension, hypoxemia, anaemia, hyperglucemia, hypothermia, a greater incidence of norepinephrine infusion, and the higher percentage of type II lesions in the head computerized tomography at admission showed in the group 1 (53,91% vs. 38,94%) (p= 2,2 mmol/L (group 2). Although, the percentage of intracranial hypertension and mortality was higher in the group 2, there was no significant difference. In the multivariate analysis, the increase of blood lactate concentration, was not independently associated as a risk factor with studied complications. Conclusions. The presence of OH in patients with moderate or severe head injury, with postresuscitation arterial pressure, according to present recommendations, is associated with a more severe head injury, showed by APACHE II and the total fluid infusion volumes in the first 48 hours. OH in head injury increases the infection rate and length of ICU stay

Brain death after severe traumatic brain injury: the role of systemic secondary brain insults.

Secondary brain insults predominantly due to hypotension are frequent among patients with fatal traumatic brain injury. We assessed the correlation between different systemic secondary brain insults and brain death in 404 patients admitted to our intensive care unit (ICU) after severe traumatic brain injury. We collated data on hypoxemia and hypotension prior to as well as the occurrence of hypoxemia, hypotension, shock, anemia, hyperglycemia, and hyperthermia within the first 24 hours after ICU admission. We also considered both the presence of extracranial injuries and the category of traumatic brain injury using computerized tomography. The 59 patients (14.6%) who developed brain death, were significantly older than patients without a fatal neurological outcome (46.1 +/- 22 vs 29.5 +/- 14.9 years; P < .0001). Intracranial mass lesions, whether surgically evacuated were more frequent among brain-dead patients. The systemic secondary brain insults significantly associated with brain death were hypoxemia, hypotension, shock, anemia, and hyperglycemia within the first 24 hours after ICU admission. After multivariate analysis, the factors that independently predicted brain death were the occurrence of shock (odds ratio [OR], 6.74; 95% confidence interval [CI], 2.85-15.84; P = .001) and older age (OR, 1.05; 95% CI, 1.03-1.07; P = .003). In conclusion, early shock seems to be the major systemic secondary brain insult associated with brain death in patients with severe traumatic brain injury. Prevention of or correction of shock might help to either decrease the occurrence of a fatal neurological outcome or in brain-dead patients to preserve organs in better condition for procurement.