Comparison of three methods to measure absolute cerebral hemoglobin concentration in neonates by near-infrared spectrophotometry.

Three methods by which to determine absolute total cerebral hemoglobin concentration (tHb in micromol/L) by near-infrared spectrophotometry (NIRS) have evolved: (1) tHbo, requiring oxygenation changes and arterial oxygen saturation measurements as a reference using a relative NIRS algorithm, (2) tHbg, using a geometrical multidistance principle and (3) tHbgo, a combination of both. The aim of this study was to compare the three methods quantitatively. Sixteen clinically stable preterm infants with a mean gestational age of 29.

Caspase-3 activity is present in cerebrospinal fluid from patients with traumatic brain injury.

Loss of neurons after traumatic brain injury (TBI) might involve dysregulated apoptosis. Activation of caspase-3 is one hallmark of apoptosis. Therefore, caspase-3 activity (cleavage of DEVD-afc) was measured in cerebrospinal fluid (CSF) samples (n=113) from 27 patients with TBI at day 1 to 14 after trauma.

Control of severe hemorrhage using C-clamp and pelvic packing in multiply injured patients with pelvic ring disruption.

Objectives: Evaluation of diagnostic and therapeutic workup in multiply injured patients with pelvic ring disruption and hemorrhagic shock.

Design: Prospective study.

Patients: Twenty consecutive multiply injured patients (ISS: 41.

Spontaneous in contrast to CD95-induced neutrophil apoptosis is independent of caspase activity.

Background: The influence of caspase inhibitors on spontaneous and on CD95-triggered apoptosis was investigated in neutrophils from healthy volunteers and compared with neutrophils from patients with severe sepsis.

Methods: To further elucidate the mechanisms of neutrophil apoptosis, isolated neutrophils from healthy volunteers (n = 9) were either stimulated with the agonistic anti-CD95 antibody (100 ng/mL) or left unstimulated in the presence or absence of the caspase inhibitors zIETD-fmk (10 micromol/L), zDEVD-fmk (10 micromol/L), or zVAD-fmk (20 micromol/L). Apoptosis was determined by measuring DNA fragmentation and Annexin-V binding in FACS, and caspase-3-like activity by DEVD-afc cleavage assay.

In vivo and in vitro evidence for extracellular caspase activity released from apoptotic cells.

While caspases play an established role as intracellular executors of apoptosis, little is known about extracellular activities of this ubiquitously expressed family of proteases. We demonstrate here that recombinant caspase-3 retained enzymatic activity in various extracellular fluids. Experiments with cell lines, primary cells, and mice with fulminant CD95-triggered hepatitis showed that significant amounts of DEVD-aminofluoromethylcoumarine-cleaving activity, indicative of active effector caspases, were released into the medium/plasma during apoptosis.

An epizootic of adenovirus-induced hemorrhagic disease in captive black-tailed deer (Odocoileus hemionus).

Ten fawns and four adult black-tailed deer (Odocoileus hemionus) in a captive herd died as a result of adenovirus-induced hemorrhagic disease. Acute, systemic infections were characterized by hemorrhagic enteropathy, pulmonary edema, and occasional ulceration of the upper alimentary tract. Localized infections were limited to the upper alimentary tract and included stomatitis, pharyngitis, mandibular osteomyelitis, and rumenitis.

Tissue oxygen saturation measured by near infrared spectrophotometry correlates with arterial oxygen saturation during induced oxygenation changes in neonates.

The aim of this study was to compare quantitatively the changes in tissue oxygen saturation (TOS), determined by two algorithms (TOSc and TOSa) based on near-infrared spectrophotometry, to the changes in arterial oxygen saturation (SaO2) measured by pulse oximetry. TOSc is an algorithm derived by the manufacturer (Critikon) based on a modified Beer-Lambert law; TOSa, our own algorithm, uses the diffusion approximation of light transport for the semi-infinite boundary condition. Slow changes of more than 3% in SaO2 were carried out in 20 mechanically ventilated neonates by altering the inspired oxygen fraction.

Can near infrared spectroscopy of the liver monitor tissue oxygenation?

Measurement of the hepatic oxygenation index by near infrared spectroscopy is a suitable method to estimate the oxygenation and can be a non-invasive means to continuously monitor tissue perfusion and to detect early haemodynamic disturbances in critically ill children.

Continuous monitoring of liver oxygenation with near infrared spectroscopy during naso-gastric tube feeding in neonates.

Near infrared spectroscopy (NIRS) is a non-invasive method of estimating the haemoglobin concentration changes in certain tissues. It is frequently used to monitor oxygenation of the brain in neonates. At present it is not clear whether near infrared spectroscopy of other organs (e.

Incidence of septic complications and multiple organ failure in severely injured patients is sex specific.

Background: Sexual hormones are potent regulators of various immune functions. Although androgens are immunosuppressive, estrogens protect against septic challenges in animal models. This study correlates sexual dimorphism with the incidence of posttraumatic complications in severely injured patients.

Serologic detection of adenoviral hemorrhagic disease in black-tailed deer in California.

An enzyme-linked immunosorbent assay (ELISA) and a serum neutralization (SN) test were developed to measure serum antibodies against the adenovirus causing hemorrhagic disease in free-ranging and captive experimentally-infected black-tailed deer (Odocoilenus hemionus columbianus) in California (USA). There was a strong (rho = 0.874) and significant (P < 0.

Relationship between procalcitonin plasma levels and severity of injury, sepsis, organ failure, and mortality in injured patients.

Objective: To compare procalcitonin (PCT) plasma levels of injured patients with the incidence and severity of systemic inflammatory response syndrome (SIRS), infection, and multiple organ dysfunction syndrome (MODS) and to assess the predictive value of PCT for these posttraumatic complications.

Design: Retrospective study comparing patients with mechanical trauma in terms of severity of injury, development of infectious complications, and organ dysfunctions.

Setting: Level I trauma center with emergency room, intensive care unit, and research laboratory.

[Bilateral hip ankylosis caused by heterotopic ossification after isolated severe craniocerebral trauma].

A 36-year old man suffered an isolated head injury with a fracture of the skull, epidural and subdural hematomas as well as brain contusion (Abbreviated Injury Scale (AIS): 5 points). The hematomas were evacuated by craniotomy. Because of high intracranial pressure (ICP) a barbiturate coma was necessary.

Clinical and pathologic features of oligodendrogliomas in two cats.

Two oligodendrogliomas in two domestic cats involved mainly the rostral brain stem, midbrain, fourth ventricle, and cerebellum. Both cats were aged neutered males presenting with clinical neurologic deficits suggestive of a brain stem lesion. Magnetic resonance imaging of both tumors demonstrated lesions with a pattern of heterogeneous contrast enhancement and multifocal lesions in one cat.

Comparison of cerebral blood volume measured by near infrared spectroscopy and contrast enhanced magnetic resonance imaging.

Cerebral blood volume (CBV) can be quantified by both near infrared spectroscopy (NIRS) and magnetic resonance imaging (MRI). The aim is to compare CBV results obtained by NIRS and MRI in adult patients. 10 adult patients, 6 females and 4 males, age median 24 (range 21 to 76) years, were included in this study.

Cyclical fluctuations in blood pressure, heart rate and cerebral blood volume in preterm infants.

Many recently published papers describe cyclical changes of cerebral circulatory variables, mainly in cerebral blood flow velocity (CBFV) performed with Doppler sonography. In this paper we focus on another important variable of cerebral circulation: on cerebral blood volume (CBV) measured by near infrared spectrophotometry (NIRS). In a retrospective analysis of NIRS measurements in 20 preterm infants (median 27 3/7 weeks of gestation), the dominating frequencies and prevalence of cyclical changes of CBV and its possible correlation with peripheral circulatory variables (mean arterial pressure and heart rate) was examined.

[Limb preservation after clostridial myonecrosis following internal fixation of a closed femoral fracture].

A 24-year-old healthy man developed Clostridium perfringens myonecrosis with severe sepsis after plating of a closed femoral fracture. The leg could be preserved by complete resection of the fascia from all muscle compartments of the leg, including the pelvitrochanteric and the iliopsoas muscles, radical removal of necrotic muscle tissue, dissection of the para-aortal infrarenal lymphatics, daily débridements over 2 weeks, and systemic antibiotic therapy. The plate was removed because of a second septic episode followed by temporary stabilization with external fixation.

The influence of a clear layer on near-infrared spectrophotometry measurements using a liquid neonatal head phantom.

It is difficult to test near-infrared spectrophotometry instruments in vivo. Therefore we constructed a liquid phantom which mimics the neonatal head. It consists of a spherical 3.

Granulocyte colony-stimulating factor inhibits neutrophil apoptosis at the local site after severe head and thoracic injury.

Background: Tissue injury from mechanical trauma often leads to secondary organ failure. Local accumulation of neutrophils and excessive release of toxic metabolites through inhibition of neutrophil apoptosis may be responsible for capillary leakage and irreversible damage of resident cells of injured tissues.

Methods: The purpose of this study was to examine the presence of apoptosis-inhibiting factors at the local site of tissue injury.

Regional differences of cerebral hemoglobin concentration in preterm infants measured by near infrared spectrophotometry.

Near infrared spectrophotometry has been used to measure total cerebral hemoglobin concentration (micromol/l) as a major indicator of the oxygen transport capacity in neonates. The aim of this study was to find out how the position of the probe influences the quality of the measurement and the actual cerebral hemoglobin concentration-values. We studied 10 healthy preterm infants with a mean gestational age of 31.

[Predictive role of IL-6 for multi-organ dysfunction syndrome MODS) in severely injured patients in the early intensive care phase].

Interleukin-6 seems to have a predictive value for the multiple organ dysfunction syndrome (MODS) in the early period after trauma.

Comparison of absolute cerebral haemoglobin concentration in neonates measured directly and by the oxygen swing method both based on near infrared spectrophotometry.

The total cerebral haemoglobin concentration (tHb in mumol/l) as a major indicator of the oxygen transport capacity is investigated in neonates. Two methods to determine tHb by near infrared spectrophotometry (NIRS) have evolved so far: The first method requires a slow oxygenation change with reference to arterial oxygen saturation (tHbo-method). The second method is based on a geometrical principle and a two channel NIRS instrument (tHbg-method).

CO2 reactivity of the cerebral hemoglobin concentration in healthy term newborns measured by near infrared spectrophotometry.

CO2 reactivity of cerebral hemoglobin concentration was studied in 16 healthy term neonates on days 1 and 4 after birth using the near infrared spectrophotometry (NIRS) technique. The aim was to establish data on the physiological range of CO2 reactivity in healthy newborns and to investigate the influence of postnatal age on it. The CO2 reactivity measured by NIRS is expressed as the change of the total cerebral hemoglobin concentration (tHbR) per change of CO2 tension in micromol/l/kPa.

[Significance of systemic inflammation in 1,278 trauma patients].

The association between the increasing severity of systemic inflammatory response syndrome (SIRS) and the incidence of post-traumatic complications and mortality was retrospectively investigated in 1278 injured patients. Patients were divided into three groups according to their Injury Severity Score (ISS) (group A: ISS > or = 9 < or = 16 points (n = 626); group B: ISS > 16 < 40 points (n = 589); group C: ISS > or = 40 points (n = 63). SIRS was defined according to the criteria of the American Consensus Conference.

Strongly enhanced serum levels of vascular endothelial growth factor (VEGF) after polytrauma and burn.

Angiogenesis is a key component of the repair mechanisms triggered by tissue injury. Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis, as it acts directly and specifically on endothelial cells. VEGF produced locally in regenerating tissue may spill over into the systemic circulation, and measuring levels of circulating VEGF may allow monitoring of angiogenesis.