Yoshiyuki Soejima

Cerebral circulation and metabolism in patients with septic encephalopathy

Cerebral circulation and metabolism in septic encephalopathy have not been well documented. The authors measured cerebral blood flow (CBF) and metabolic rate for oxygen (CMRO2) in six patients with septic encephalopathy associated with multiple organ failure (three to five organs). They found that CBF and CMRO2 were significantly lower than awake control values of 46 +/- 2 to 28 +/- 3 mL/100g/min (mean +/- SEM) and 3.1 +/- 0.2 to 1.2 +/- 0.2 mL/100g/min, respectively. Cerebral vascular resistance (CVR) and cerebral circulatory index (CCI:CBF/CMRO2) were significantly higher than the control values of 2.0 +/- 0.1 to 3.0 +/- 0.4 mm Hg/mL/100g/min and 15.1 +/- 0.8 to 24.2 +/- 3.3, respectively. At the time of cerebral circulatory and metabolic measurements, their consciousness varied between 4 and 10 as evaluated by the Glasgow coma scale. The electroencephalogram showed diffuse slow wave activity and the latency of the auditory brain stem evoked response was prolonged in four of six patients. Computed brain tomography showed either no abnormality or mild atrophy. It is concluded that CBF and CMRO2 are disproportionally decreased during septic encephalopathy in association with dysfunction of the CNS and decreased electrical activity.

Feasibility of the Titration Method of Mild Hypothermia in Severely Head-injured Patients with Intracranial Hypertension

OBJECTIVE Clinical strategy to maximize effectiveness and to minimize adverse influences remains to be determined for mild hypothermia therapy for traumatic brain injury. This study was conducted to evaluate the clinical feasibility of the titration method of mild hypothermia in severely head-injured patients in whom a reduction in intracranial pressure was regarded as the target effect. METHODS Nine consecutive patients with severe head injury were studied. Patient age ranged between 18 and 66 years, Glasgow Coma Scale scores were equal to or less than 8, and intracranial pressures were equal to or greater than 20 mm Hg despite removal of intracranial hematoma and drugs, including glycerol and thiopental. During a maximum of 6 days of hypothermia therapy, jugular venous blood or cerebrospinal fluid temperature was titrated to reduce intracranial pressure to less than 20 mm Hg by means of repeated intragastric cooling with our nasoduodenal tube and surface cooling. The feasibility and the effects on systemic complications of this titration method of mild hypothermia were evaluated. RESULTS Intracranial pressure variably decreased from before to 3 hours after the beginning of all procedures of cooling. The mean intracranial pressure significantly decreased from 24 to 15 mm Hg with cooling, while temperature reduced an average of 2.0 degrees C. Four patients had systemic infection complications. Increased C-reactive protein and decreased platelet count were observed in all patients during hypothermia. The incidence of good recovery and moderate disability according to the Glasgow Outcome Scale was seven of nine patients. CONCLUSION The titration method of mild hypothermia to control intracranial hypertension in severely head-injured patients is clinically feasible. However, the method failed to reduce the incidence of infectious and hematological complications.

Qualitative comparison of carbon dioxide-induced change in cerebral near-infrared spectroscopy versus jugular venous oxygen saturation in adults with acute brain disease

OBJECTIVE To compare carbon dioxide-induced changes in cerebral oxy- and deoxyhemoglobin, measured by near-infrared spectroscopy, with those changes in jugular venous oxygen saturation in adult patients with acute brain disease. DESIGN A prospective study. SETTING The medical and surgical intensive care unit of a university hospital. PATIENTS Nine patients with head trauma (n = 4), cerebrovascular disease (n = 3), and meningitis (n = 2). A total of ten measurements were done, while PaCO2 was increased from hypocapnia toward normocapnia in the nine patients. INTERVENTIONS Arterial and jugular bulb catheterization, and intracranial pressure monitoring were performed as a part of the clinical intervention. An increase in PaCO2 was obtained by inhalation of CO2 and, if necessary, by reducing the ventilator rate. MEASUREMENTS AND MAIN RESULTS In each patient, the position of the jugular bulb catheter was ascertained by skull roentgenography. Near-infrared spectroscopic values for oxy- and deoxyhemoglobin were set at zero at the beginning of the study. An increase in PaCO2 from 29 +/- 1 (SEM) torr (3.9 +/- 0.2 kPa) to 39 +/- 2 torr (5.2 +/- 0.3 kPa) was accompanied by a significant increase in jugular venous oxygen saturation from 63 +/- 3% to 76 +/- 3%; a significant increase in oxyhemoglobin of 3.5 +/- 0.9 mumol/L (of the brain tissue); and a significant decrease in deoxyhemoglobin of 1.5 +/- 0.4 mumol/L. In nine of ten measurements, the slopes of changes in oxyhemoglobin against the slopes of change in jugular venous oxygen saturation were very similar. In one patient, oxyhemoglobin changed negligibly while jugular venous oxygen saturation increased by 20%. CONCLUSIONS Jugular venous oxygen saturation consistently demonstrates cerebrovascular responsiveness to CO2. The direction and magnitude of changes in cerebral oxyhemoglobin, measured by near-infrared spectroscopy, were similar to those changes in jugular venous oxygen saturation in most of our cases. Interpretation of a negligible change in oxyhemoglobin in one patient, despite an obvious increase in jugular venous oxygen saturation, requires further study comparing near-infrared spectroscopy with standard techniques.

Local cerebral glucose utilization in septic rats.

To identify cortical and subcortical structures in the brain which are associated with septic encephalopathy, local cerebral glucose utilization (LCGU) in the 31 discrete regions were evaluated with a quantitative (14C)-2. deoxyglucose autoradiographic method in the septic rat model. Sepsis was produced by cecal ligation and punctures. Forty rats were subjected to behavioral study and divided into two groups (control, n = 15; sepsis, n = 25). Septic rats died within 36 h, and the rats developed behavioral depression, and showed EEG slowing and an increase in pain threshold. The latter was evaluated by a tail flick method within 8 h after the surgical procedures, while control rats did not show significant change in either behaviors or pain threshold. In another study, LCGU was measured when behavioral depression, increase in pain threshold, and EEC slowing developed in the sepsis group (n = 7). In this group, the mean LCGU in auditory and parietal cortices, lateral geniculate, superior colliculus, hippocampus, and locus ceruleus was 95, 74, 67, 69, 72, and 53 μmol.100 g−1. min−1, being lower by 23%, 22%, 18%, 19%, 14%, and 27% than that in the sham-operated control group (n = 7), respectively. However, the mean LCGU in septal and raphe nuclei was 52 and 84 μmol.100 g−1. min−1, being significantly higher by 27% and 33% than that in the control group, respectively. These results suggest that septic encephalopathy is associated with metabolic changes in the discrete brain regions, which are related to the serotonergic or noradrenergic system. (Crit Care Med 1990; 18:423)

HBV-related fulminant hepatic failure: successful intensive medical therapy in a candidate for liver transplantation

Fulminant hepatic failure (FHF) usually has a fatal prognosis without liver transplantation. We describe the case of a woman who developed FHF, and was evaluated as a candidate for liver transplantation, but who was cured without transplantation through intensive medical care that included glucagon-insulin therapy, methylprednisolone pulse therapy, interferon beta and lamivudine administration, cyclosporine administration, and high-volume hemodiafiltration and plasma exchange. In a patient with FHF who is a candidate for liver transplantation but for whom the transplantation cannot be performed for some reason, intensive medical therapy, including regeneration-promoting therapy, immunosuppressive therapy, antiviral therapy, and vigorous hepatic support, should be carried out.

Heart rate fluctuations in post‐operative and brain‐death patients

The power spectra of heart rate in patients receiving intensive care were calculated and the relation between gain and frequency discussed. 1/f fluctuations in heart rate can be observed in both post‐operative and brain‐death patients in the intensive care unit. These results suggested that 1/f fluctuations are a fundamental human phenomenon.