Sleep-wake disturbances 6 months after traumatic brain injury: a prospective study

Sleep-wake disturbances (SWD) are common after traumatic brain injury (TBI). In acute TBI, we recently found decreased CSF levels of hypocretin-1, a wake-promoting neurotransmitter. In the present study, we aimed to delineate the frequency and clinical characteristics of post-traumatic SWD, to assess CSF hypocretin-1 levels 6 months after TBI, and to identify risk factors for posttraumatic SWD. A total of 96 consecutive patients were enrolled within the first 4 days after TBI. Six months later, out of 76 TBI patients, who did not die and who did not move to foreign countries, we included 65 patients (86%, 53 males, mean age 39 years) in our study. Patients were examined using interviews, questionnaires, clinical examinations, computed tomography of the brain, laboratory tests (including CSF hypocretin-1 levels, and HLA typing), conventional polysomnography, maintenance of wakefulness and multiple sleep latency tests (MSLT) and actigraphy. Potential causes of post-traumatic SWD were assessed according to international criteria. New-onset sleep-wake disturbances following TBI were found in 47 patients (72%): subjective excessive daytime sleepiness (EDS; defined by the Epworth Sleepiness Scale ≥10) was found in 18 (28%), objective EDS (as defined by mean sleep latency <5 min on MSLT) in 16 (25%), fatigue (daytime tiredness without signs of subjective or objective EDS) in 11 (17%), post-traumatic hypersomnia ‘sensu strictu' (increased sleep need of ≥2 h per 24 h compared to pre-TBI) in 14 (22%) patients and insomnia in 3 patients (5%). In 28 patients (43% of the study population), we could not identify a specific cause of the post-traumatic SWD other than TBI. Low CSF hypocretin-1 levels were found in 4 of 21 patients 6 months after TBI, as compared to 25 of 27 patients in the first days after TBI. Hypocretin levels 6 months after TBI were significantly lower in patients with post-traumatic EDS. There were no associations between post-traumatic SWD and severity or localization of TBI, general clinical outcome, gender, pathological neurological findings and HLA typing. However, post-traumatic SWD correlated with impaired quality of life. These results suggest that sleep-wake disturbances, particularly EDS, fatigue and hypersomnia are common after TBI, and significantly impair quality of life. In almost one out of two patients, post-traumatic SWD appear to be directly related to the TBI. An involvement of the hypocretin system in the pathophysiology of post-traumatic SWD appears possible. Other risk factors predisposing towards the development of post-traumatic SWD were not identifie

Deutschland 1997: Schwacher, exportgetragener Aufschwung

Mit dem Jahresausblick für 1997 wird die Konjunkturprognose von Mitte 1996 für das Jahr 1997 aktualisiert. Die gesamtwirtschaftliche Produktion erhält im Jahr 1997 infolge der anziehenden Weltkonjunktur und der Normalisierung des Außenwerts der D-Mark Impulse vom Export. Die Selbstverstärkung des Aufschwungs wird schwach bleiben, da die verfügbaren Einkommen der privaten Haushalte nur geringen Spielraum für zusätzlichen Konsum bieten. Das Bruttoinlandsprodukt wird 1997 mit 2,1 % expandieren. Der Aufschwung bleibt jedoch zu schwach, um einen Abbau der Arbeitslosigkeit zu ermöglichen.

Brain metabolism is significantly impaired at blood glucose below 6 mM and brain glucose below 1 mM in patients with severe traumatic brain injury

ABSTRACT: INTRODUCTION: The optimal blood glucose target following severe traumatic brain injury (TBI) must be defined. Cerebral microdialysis was used to investigate the influence of arterial blood and brain glucose on cerebral glucose, lactate, pyruvate, glutamate, and calculated indices of downstream metabolism. METHODS: In twenty TBI patients, microdialysis catheters inserted in the edematous frontal lobe were dialyzed at 1 mul/ min, collecting samples at 60 minute intervals. Occult metabolic alterations were determined by calculating the lactate- pyruvate (L/P), lactate- glucose (L/Glc), and lactate- glutamate (L/Glu) ratios. RESULTS: Brain glucose was influenced by arterial blood glucose. Elevated L/P and L/Glc were significantly reduced at brain glucose above 1 mM, reaching lowest values at blood and brain glucose levels between 6- 9 mM (P 5 mM. Pathogenity of elevated glutamate appears to be relativized by L/Glu and suggests to exclude insulin- induced brain injury

Differential temporal profile of lowered blood glucose levels (3.5 to 6.5 mmol/l versus 5 to 8 mmol/l) in patients with severe traumatic brain injury

INTRODUCTION: Hyperglycaemia is detrimental, but maintaining low blood glucose levels within tight limits is controversial in patients with severe traumatic brain injury, because decreased blood glucose levels can induce and aggravate underlying brain injury. METHODS: In 228 propensity matched patients (age, sex and injury severity) treated in our intensive care unit (ICU) from 2000 to 2004, we retrospectively evaluated the influence of different predefined blood glucose targets (3.5 to 6.5 versus 5 to 8 mmol/l) on frequency of hypoglycaemic and hyperglycaemic episodes, insulin and norepinephrine requirement, changes in intracranial pressure and cerebral perfusion pressure, mortality and length of stay on the ICU. RESULTS: Mortality and length of ICU stay were similar in both blood glucose target groups. Blood glucose values below and above the predefined levels were significantly increased in the 3.5 to 6.5 mmol/l group, predominantly during the first week. Insulin and norepinephrine requirements were markedly increased in this group. During the second week, the incidences of intracranial pressure exceeding 20 mmHg and infectious complications were significantly decreased in the 3.5 to 6.5 mmol/l group. CONCLUSION: Maintaining blood glucose within 5 to 8 mmol/l appears to yield greater benefit during the first week. During the second week, 3.5 to 6.5 mmol/l is associated with beneficial effects in terms of reduced intracranial hypertension and decreased rate of pneumonia, bacteraemia and urinary tract infections. It remains to be determined whether patients might profit from temporally adapted blood glucose limits, inducing lower values during the second week, and whether concomitant glucose infusion to prevent hypoglycaemia is safe in patients with post-traumatic oedema

Increasing hematocrit above 28% during early resuscitative phase is not associated with decreased mortality following severe traumatic brain injury

Background: To prevent iatrogenic damage, transfusions of red blood cells should be avoided. For this, specific and reliable transfusion triggers must be defined. To date, the optimal hematocrit during the initial operating room (OR) phase is still unclear in patients with severe traumatic brain injury (TBI). We hypothesized that hematocrit values exceeding 28%, the local hematocrit target reached by the end of the initial OR phase, resulted in more complications, increased mortality, and impaired recovery compared to patients in whom hematocrit levels did not exceed 28%. Methods: Impact of hematocrit (independent variable) reached by the end of the OR phase on mortality and morbidity determined by the extended Glasgow outcome scale (eGOS; dependent variables) was investigated retrospectively in 139 TBI patients. In addition, multiple logistic regression analysis was performed to identify additional important variables. Findings: Following severe TBI, mortality and morbidity were neither aggravated by hematocrit above 28% reached by the end of the OR phase nor worsened by the required transfusions. Upon multiple logistic regression analysis, eGOS was significantly influenced by the highest intracranial pressure and the lowest cerebral perfusion pressure values during the initial OR phase. Conclusions: Based on this retrospective observational analysis, increasing hematocrit above 28% during the initial OR phase following severe TBI was not associated with improved or worsened outcome. This questions the need for aggressive transfusion management. Prospective analysis is required to determine the lowest acceptable hematocrit value during the OR phase which neither increases mortality nor impairs recovery. For this, a larger caseload and early monitoring of cerebral metabolism and oxygenation are indispensabl

Differential influence of arterial blood glucose on cerebral metabolism following severe traumatic brain injury

INTRODUCTION: Maintaining arterial blood glucose within tight limits is beneficial in critically ill patients. Upper and lower limits of detrimental blood glucose levels must be determined. METHODS: In 69 patients with severe traumatic brain injury (TBI), cerebral metabolism was monitored by assessing changes in arterial and jugular venous blood at normocarbia (partial arterial pressure of carbon dioxide (paCO2) 4.4 to 5.6 kPa), normoxia (partial arterial pressure of oxygen (paO2) 9 to 20 kPa), stable haematocrit (27 to 36%), brain temperature 35 to 38 degrees C, and cerebral perfusion pressure (CPP) 70 to 90 mmHg. This resulted in a total of 43,896 values for glucose uptake, lactate release, oxygen extraction ratio (OER), carbon dioxide (CO2) and bicarbonate (HCO3) production, jugular venous oxygen saturation (SjvO2), oxygen-glucose index (OGI), lactate-glucose index (LGI) and lactate-oxygen index (LOI). Arterial blood glucose concentration-dependent influence was determined retrospectively by assessing changes in these parameters within pre-defined blood glucose clusters, ranging from less than 4 to more than 9 mmol/l. RESULTS: Arterial blood glucose significantly influenced signs of cerebral metabolism reflected by increased cerebral glucose uptake, decreased cerebral lactate production, reduced oxygen consumption, negative LGI and decreased cerebral CO2/HCO3 production at arterial blood glucose levels above 6 to 7 mmol/l compared with lower arterial blood glucose concentrations. At blood glucose levels more than 8 mmol/l signs of increased anaerobic glycolysis (OGI less than 6) supervened. CONCLUSIONS: Maintaining arterial blood glucose levels between 6 and 8 mmol/l appears superior compared with lower and higher blood glucose concentrations in terms of stabilised cerebral metabolism. It appears that arterial blood glucose values below 6 and above 8 mmol/l should be avoided. Prospective analysis is required to determine the optimal arterial blood glucose target in patients suffering from severe TBI

Deutschland 1998/99 - Binnennachfrage stärkt Aufschwung

Der Aufsatz analysiert und prognostiziert die konjunkturelle Entwicklung in Deutschland und im Euroraum in ausführlicher Form für das laufende Jahr 1998 und das Folgejahr 1999. Die Impulse aus dem Ausland bleiben im Prognosezeitraum kräftig, auch wenn sie infolge der negativen Auswirkungen, die direkt und indirekt auf den deutschen Export von der Ausbreitung des Krisenherdes in Asien ausgehen, an Stärke verlieren. Die Binnenkonjunktur wird 1998 als Antriebskraft der gesamtwirtschaftlichen Produktion gegenüber der Auslandsnachfrage an Bedeutung gewinnen und im Jahr 1999 in etwa mit ihr gleichziehen. In Ostdeutschland wird dabei die Schwächephase langsam überwunden, so dass im Jahr 1999 hinsichtlich der Wachstumsdynamik fast wieder zu Westdeutschland aufgeschlossen werden kann. Die Kräftigung des konjunkturellen Aufschwungs zeigt auch erste Spuren am Arbeitsmarkt, vor allem in Westdeutschland.

Development, design, and realization of a proficiency test for the forensic determination of shooting distances - FDSD 2015

Within the framework of the ENFSI Expert Working Group Firearms/GSR a novel proficiency test on the Forensic Determination of Shooting Distances – FDSD 2015 – was implemented. This proficiency test was developed out of collaborative studies which were previously carried out by a number of pre-selected ENFSI laboratories. The aim of this test was to assess the laboratories’ performance in visualizing the lead patterns on a shot object, and compare the questioned patterns with provided test shot patterns. The participating laboratories were requested to estimate the presumed shooting distance following their individual laboratory specific methods (SOPs) for shooting distance/muzzle-to-target determination. The submitted results were compiled by means of z scores according to the IUPAC and EURACHEM guidelines, and an extended statistical evaluation was performed. This is one of the first proficiency tests in the field of qualitative forensic methods where z scores were successfully utilized. This paper summarizes the results of the study and presents the overall performance of the participating laboratories

Development, design, and realization of a proficiency test for the forensic determination of shooting distances - FDSD 2015

Within the framework of the ENFSI Expert Working Group Firearms/GSR a novel proficiency test on the Forensic Determination of Shooting Distances – FDSD 2015 – was implemented. This proficiency test was developed out of collaborative studies which were previously carried out by a number of pre-selected ENFSI laboratories. The aim of this test was to assess the laboratories’ performance in visualizing the lead patterns on a shot object, and compare the questioned patterns with provided test shot patterns. The participating laboratories were requested to estimate the presumed shooting distance following their individual laboratory specific methods (SOPs) for shooting distance/muzzle-to-target determination. The submitted results were compiled by means of z scores according to the IUPAC and EURACHEM guidelines, and an extended statistical evaluation was performed. This is one of the first proficiency tests in the field of qualitative forensic methods where z scores were successfully utilized. This paper summarizes the results of the study and presents the overall performance of the participating laboratories