[Role of endovascular surgery in presence of rupture of the thoracic aorta in patients with severe multisystemic post-traumatic surgical lesions]. / Ruolo della chirurgia endovascolare nelle rotture aortiche del politraumatizzato con lesioni polidistrettuali di pertinenza chirurgica.

The endovascular treatment (ET) of traumatic rupture of the thoracic aorta (TRTA) may represent, particularly in patients with severe multisystemic post-traumatic surgical lesions, an alternative approach to traditional surgery. We observed (October 2001- November 2004) 5 male patients (age: range 23-42 years - average 32,4) affected by TRTA (3 isthmic aortic ruptures - 2 distal descending thoracic aorta ruptures), all successfully treated with an endovascular approach. The Glasgow Coma Score (GCS) ranged between 5 and 13. After performing resuscitation manoeuvres, all patients were investigated with total body CT scans in order to evaluate the thoracic aorta and to identify associated visceral lesions. In 4 cases were evident associated visceral lesions (3 cases: bone, abdominal and neurosurgical trauma - 1 case: bone, abdominal, neurosurgical and thoracic trauma). All the procedures were performed in the operative room using DSA (Digital Subtraction Angiography). The mean operating time was 105 minutes (range 80 - 125). We didn't observed early and late complications (follow-up: average 24 months, range 12-36). In conclusion the ET of TRTA represents in 'critical' patients with severe polytrauma an alternative approach to traditional surgery in order to 'stabilizing' the cardiovascular clinical parameters and to treating 'safety' the other associated surgical lesions.

Thermal response of contrast agent microbubbles: preliminary results from physico-chemical and US-imaging characterization.

Hyperthermia (HT) is a therapeutic strategy based on the selective damaging of tumoral cells when heated at temperatures in the range 41-45 degrees C. We are currently investigating the feasibility of Ultrasound (US) imaging to perform a non-invasive, efficient and cost effective temperature monitoring of heated tissues. Commercial US contrast agents (Sonovue, Bracco), consisting in microbubbles of SF(6) coated with a phospholipidic shell, greatly improve the US echo signal from tissues. Further investigations have been performed, consisting in physico-chemical and US-imaging characterization. In conclusion, we demonstrate that Sonovue microbubbles reach their maximal diameter at 40 degrees C, and then a sharp decrease is observed, possible due to the occurrence of gel-sol transition of the phospholipidic shell. At the same temperature the maximal backscattering intensity is predicted and actually experimentally observed. Sonovue, as well as other contrast agents based only on phospholipids, are, therefore, not suitable for use as non-invasive temperature monitoring medium since it is sensitive to temperatures below the hyperthermic range. Although microbubbles are in principle thermally effective, other coating materials should be investigated in order to increase their operative thermal range.

Capillary regression in vascular endothelial growth factor-deficient skeletal muscle.

Skeletal muscle angiogenesis is an important physiological adaptation to increased metabolic demand, possibly dependent on vascular endothelial growth factor (VEGF), the increased expression of which is a known early response to exercise. To test the hypothesis that VEGF is essential to muscle capillary maintenance, we evaluated the consequences of targeted skeletal muscle inhibition of VEGF expression in postnatal, cage-confined VEGFloxP(+/+) mice. To delete VEGF, cre recombinase expression was accomplished using direct intramuscular injection of a recombinant adeno-associated cre recombinase expressing viral vector. Four weeks postinfection, VEGF-inactivated regions revealed 64% decreases in capillary density and capillary-to-fiber ratio. Substantial apoptosis was also observed in VEGF-depleted regions. There was no evidence of rescue at 8 wk, with a persistent 67% reduction in capillary-to-fiber ratio and a 69% decrease in capillary density. These data implicate VEGF as an essential survival factor for muscle capillarity and also demonstrate insufficient VEGF-dependent signaling leads to apoptosis in mouse skeletal muscle.

Seasonal variation in weight-for-age in a pediatric emergency room.

OBJECTIVE: The authors assess seasonal variations in the prevalence of low weight-for-age among young children visiting the pediatric emergency room of a city hospital. METHODS: We analyzed data on 11,118 children ages 6 to 24 months who visited the Boston City Hospital Pediatric Emergency Department between July 1989 and June 1992. Medical diagnoses were documented on a randomly selected subsample of 1,569 children. In addition, a questionnaire about food insecurity was administered to a convenience subsample of 269 families with children under 3 years of age. RESULTS: The percentage of children visiting the emergency room with weight-for-age below the fifth percentile was significantly higher for the three months following the coldest months than for the remaining months of the year, controlling for year of measurement. In the subsample, gastrointestinal illness was correlated with both season of measurement and weight-for-age, but the seasonal effect remained for the entire sample after controlling for dehydration. The questionnaire data suggested a relationship between economic stress and food insecurity that might help explain the seasonal effect. Families who were without heat or who were threatened with utility turnoff in the previous winter were twice as likely as other families to report that their children were hungry or at risk for hunger. CONCLUSIONS: Winter and early spring constituted periods of increased nutritional risk in the in this sample of predominantly low-income children, probably because of the increased caloric associated with cold stress and infections. Further research is needed to assess whether decreased caloric availability due to high heating costs, a "heat or eat" effect, also contributes to this phenomenon.

[Blood levels of cortisol and prolactin. Are they indices of the degree of protection against surgical stress?]. / Livelli ematici di cortisolo e prolattina. Indici del grado di protezione dallo stress chirurgico?

The paper evaluates the level of analgesic protection by assaying cortisol and prolactin levels in two groups of 20 patients each undergoing general anesthesia using two different techniques: TIVA with propofol and fentanyl, and BPN-nitrous oxide. The results showed that TIVA caused a very slight increase in residue cortisol which was, however, within normal limits. With BPN-nitrous oxide anesthesia there was a greater increase in cortisol, reaching a statistically significant level in blood collected one hour after the end of surgery. With regard to prolactin, there was a marked increase in this hormone using both techniques although in percentage terms this increase was lower in TIVA. These results show that plasma prolactin is a more sensitive test than cortisol assay in evaluating antalgic protection and that, of the two anesthetic techniques used, the most protective appears to be TIVA with propofol and fentanyl.

[Poisoning caused by chronic exposure to volatile anesthetics. Molecular mechanisms and risk anesthetics]. / Tossicità da esposizione cronica agli anestetici volatili. Meccanismi molecolari ed anestetici a rischio.

The possible molecular mechanisms potentially inducing occupational disease among operating room personnel were examined; and the really dangerous anaesthetic agents were identified. As concerns the molecular mechanisms of parenchymatous injury, we surveyed: those connected with free radicals and biological reactive intermediates produced during halothane and nitrous oxide biotransformation; those coming from inorganic fluoride produced during biotransformation of any halogenated anaesthetic agent, and from inorganic bromide released during halothane metabolism; and, finally, those linked to vitamin B12 inactivation from nitrous oxide. Halothane and nitrous oxide can be considered as really dangerous anaesthetic agents for operating room personnel, and enflurane as an agent with marginal toxic power. On the contrary, isoflurane is a safe, useful compound, totally devoided of viscerotoxic effects. From data examined it is possible to conclude that an isoflurane-oxygen-air anaesthesia is safe for operating room personnel more than a balanced anaesthesia with intravenous drugs and nitrous oxide as maintenance.

Evaluation of reproterol's effectiveness in preventing exercise-induced bronchospasm in children.

The authors have evaluated the effectiveness of the protection of a new beta 2-adrenergic compound, reproterol, against broncho-constriction induced by physical exercise in a group of individuals of paediatric age sensitive to broncho-stimulation. This study has been carried out comparing reproterol with salbutamol, using placebo as a control, following a randomized single-blind crossover trial. The provocation test has been performed following the instructions of the Italian Society of Paediatrics. The drugs have been administered in the oral liquid form at the dose of 0.28 mg/kg and 0.1 mg/kg of reproterol and salbutamol, respectively. The two substances have shown a similar preventive effectiveness in controlling exercise-induced asthma up to 2 hours from administration with reproterol having a stronger action at the beginning of the observation.