Stroke volume variation as a predictor of fluid responsiveness in patients undergoing airway pressure release ventilation.

We investigated the effectiveness of stroke volume variation (SVV) shown by the Vigileo-FloTrac™ system (Edwards Lifesciences, Irvine, CA) to predict fluid responsiveness in patients undergoing airway pressure release ventilation (APRV). All 80 patients mechanically ventilated in the intensive care unit of our hospital from April to November 2010 were included in this study. After starting APRV, Ringer's lactate solution was administered for 30 minutes. Haemodynamic variables including heart rate, mean arterial pressure, cardiac index (CI), stroke volume index (SVI) and SVV were measured before and after volume loading. SVV before volume loading was significantly correlated with absolute change in SVV (ΔSVV) and percentage change in stroke volume index (ΔSVI) after volume loading (ΔSVV: P<0.05, r2=0.534; ΔSVI: P<0.05, r2=0.217). Of the 80 patients, 38 (47.5%) were responders to intravascular volume expansion (increase in CI≥15%) and 42 (52.5%) were non-responders (increase in CI<15%). Receiver operating characteristic (ROC) curves were generated for SVV and central venous pressure by varying the discriminating threshold of the variable and areas under the ROC curves were calculated. The areas under the ROC curves were 0.793 for SVV (95% confidence interval: 0.709-0.877) and 0.442 for central venous pressure (95% confidence interval: 0.336-0.549), which were significantly different (P<0.05). The optimal threshold value of SVV to discriminate between responders and nonresponders was 14% (sensitivity: 78.9%; specificity: 64.3%). We found that SVV was able to predict fluid responsiveness in patients undergoing APRV with acceptable levels of sensitivity and specificity.

Determinants of outcomes following acute child encephalopathy and encephalitis: pivotal effect of early and delayed cooling.

BACKGROUND: Acute encephalopathy/encephalitis is one of the most important causatives of mortality and neurological deficit during childhood. The aim of this retrospective observational study was to investigate clinical variables and therapeutic options associated with the outcome of children with acute encephalopathy/encephalitis. METHODS: Relationships between the clinical information at admission and the neurological outcome evaluated using Pediatric Cerebral Performance Category Scale (PCPC) at 12 months after admission were assessed in 43 patients who were treated at 10 Japanese paediatric intensive care units. RESULTS: Sixteen patients were cared for at normothermia, whereas mild hypothermia was applied to 27 children. In univariate analysis, ages ≤ 18 months, marked elevation in serum lactate dehydrogenase (LD) and aspartate transaminase, diagnosis of either acute necrotising encephalopathy or haemorrhagic shock and encephalopathy syndrome and longer hypothermic periods were associated with increased risks of death or severe neurological deficit, whereas hypothermia showed pivotal effects: the outcome of children cooled after 12 h of diagnosis was statistically invariant with normothermic children, but was significantly worse compared with children cooled ≤ 12 h. In multivariate analysis, younger ages and elevated serum LD were associated with adverse outcomes, whereas early initiation of cooling was related to favourable outcomes. For normothermic children, PCPC scores were dependent on the computed tomographic findings suggestive of cerebral oedema, serum LD levels and Glasgow Coma Scale at admission. For hypothermic children, PCPC scores depended on longer delays in cooling initiation. CONCLUSION: Without therapeutic hypothermia, the outcome of children was determined by variables suggestive of the severity of encephalopathy/encephalitis at admission. Hypothermia may have pivotal impacts on the outcome of children according to the timing of cooling initiation following acute encephalopathy/encephalitis.

[Studies on surfactant replacement therapy in pediatric measles pneumonitis].

Measles pneumonitis, as well as encephalitis, is the most important complication associated with mortality in measles. Many medications including steroids and vitamin A have been applied to pediatric measles pneumonitis. However, the efficacy of such medication has not yet been established. This study is aimed at evaluating the effectiveness of surfactant replacement therapy in pediatric measles pneumonitis. Five patients (aged 1-2 years) with measles pneumonitis were transferred to our emergency center. On the transferred day, Surfactant-TA was administered by intratracheal method. After administration of surfactant, PaO2/FIO2 increased from 63.6 +/- 11.0 (mean +/- SE) to 206.2 +/- 54.1 in an hour and to 163.8 +/- 34.8 in 24. At the same time, the CO2 elimination and the dynamic compliance were improved. Because of these effects, the peak inspiratory pressure employed in mechanical ventilation could be reduced. It is concluded that surfactant replacement therapy can prevent the patients with measles pneumonitis from hypoxemia and ventilation-induced lung injury. However, further study is needed to maintain the improved oxygenation. Recently, it is reported that the effect of exogenous surfactant on oxygenation and activity of pulmonary neutrophils is regulated by the amount and/or concentration of administered surfactant. Therefore, it is an urgent issue to find out the optimum amount and concentration of exogenous surfactant used clinically.

[A case of Salmonella subdural empyema developed in chronic subdural hematoma].

A case of Salmonella subdural empyema developed in chronic subdural hematoma (Infected Subdural Hematoma; ISH) was reported. A 64-year-old man had been in a nearby hospital due to myelodysplastic syndrome with cerebral infarction for two months. His condition there had been almost uneventful. But spike fever occurred and the patient became drowsy two days before his transfer to our medical center. His consciousness level deteriorated progressively and CT scan showed a right chronic subdural hematoma. He had had no history of head trauma in the previous two months. On admission to our center, his consciousness level was semicoma with anisocoria. An emergency operation was performed via a single burr hole initially. From the burr hole, old bloody fluid accompanied by yellowish pus was obtained. Thus so-called ISH was diagnosed and the craniotomy was carried out. Gram stain of the specimen revealed gram negative rods. Although an epileptic state developed after the operation, it was controlled by barbiturate coma therapy for 3 days, followed by phenytoin administration. Fever subsided gradually with antibiotics sensitive to the bacteria and his anisocoria disappeared on the 4th postoperative day. In this case, Salmonella enteritidis was detected from bacterial culture both of the specimen and of the arterial blood. Salmonella enteritidis might have been implanted on the capsule of the chronic subdural hematoma by bacteremia derived from immunological dysfunction due to myelodysplastic syndrome. In conclusion, the possibility of ISH should be considered in chronic subdural hematoma patients with immunological dysfunction.

Blood purification for crush syndrome.

At least 372 people developed crush syndrome after they were injured by the Great Hanshin-Awaji Earthquake. Of these, 23 were transferred to Osaka City General Hospital from the disaster area. The serum creatinine kinase (CK) of each of the 23 patients exceeded 10,000 IU/L. Sixteen of these patients were treated with various methods of blood purification including hemodialysis (HD), plasma exchange (PE), and continuous hemodiafiltration (CHDF). The effectiveness on each method of blood purification was evaluated in this study based on the clearance of myoglobin and the length of time until recovery from acute renal failure (ARF). None of the patients died, and none suffered from ARF longer than 2 months. The length of time required for blood purification was significantly correlated with the serum CK and myoglobin levels on admission. The serum myoglobin levels decreased linearly regardless of the method of blood purification used. Our findings showed that the severity of ARF that occurred in association with crush injury was proportional to the amount of crushed muscle and that once ARF had developed, the clearance of myoglobin was not affected by any of the blood purification methods tested including HD, PE, and CHDF. Therefore, the method of blood purification employed for crush syndrome should be selected for its effectiveness in treating ARF, rather than the elimination of myoglobin.