Perioperative analgesia in pulmonary surgery.

AIM: In pulmonary surgery many studies have shown how pain associated with residual doses of anaesthetic drugs can cause a decrease in pulmonary volumes and depression of the cough reflex. Both these phenomena are responsible for a rising incidence of postoperative mortality and morbidity. The most widely used postoperative analgesic techniques are continuous systemic analgesia and epidural analgesia. The aim of this study is to verify the advantages and the disadvantages of both analgesic techniques. METHODS: Fifty patients, undergoing pulmonary surgery, were recruited and divided, after randomization into 2 groups. Patients included in A group received an epidural administration of naropina 0.2%+fentanyl 4 microg/mL by elastomeric pump (rate 5 ml/h). Patients included in B group received an ev continuous infusion of tramadol 600 mg+ketorolac trometamina 120 mg+ranitidina 200 mg+ondansetron 16 mg by elastomeric pump (rate 5 ml/h for 48 hours). RESULTS: Both groups showed good analgesic effects. Pain rest relief was between 3 and 1.7 points in group B and between 2.5 and 0.4 points in group A. Incident pain was 4.8 at awakening time and it decreased to 4 after 48 hours in group B while in group A it was from 3.2 to 1.8 in the same period of B group. CONCLUSIONS: Our data show that both analgesic techniques are able to guarantee a good rest pain relief after thoracotomy. Epidural analgesia showed more efficacy as far as incident pain relief but it was more difficult to realise and it showed less acceptance by patients.

Perioperative thoracic epidural analgesia in aortic surgery: role of levobupivacaine.

AIM: Perioperative pain management in patients undergoing surgery is an essential target in order to improve intraoperative outcome and reduce postoperative complications occurrence. The combination of a local anesthetic with an opiate for epidural administration can ensure both analgesic effect (opiate) and neuroendocrine protection (local anesthetic). Levobupivacaine, S(-)-enantiomer form of bupivacaine, produces a sensitive-motor blockade similar to the racemate, with less cardiotoxicity; also ropivacaine is not cardiotoxic, but it has less anesthetic efficacy than levobupivacaine; both anesthetics could be administered through the epidural catheter in order to ensure adequate analgesia without any hemodynamic effects. Aim of our study was to evaluate a thoracic epidural analgesia for abdominal aortic surgery. METHODS: Through a randomized mono-blind study, involving 28 patients undergoing aortic surgery, we performed a clinical evaluation of 2 different perioperative thoracic epidural analgesic techniques; 2 different local anesthetics (levobupivacaine versus ropivacaine) in combination with the same opiate (fentanyl) were compared. RESULTS: The results obtained show that both techniques ensure an excellent perioperative analgesia without any cardiotoxicity, with only moderate adverse effects due to opiate; the absence of postoperative mortality (within 30 days from operation) and the modest perioperative morbidity underline the qualities of this analgesic technique. CONCLUSION: The combination of fentanyl with levobupivacaine or ropivacaine for use in thoracic epidural administration ensured both analgesic and neuroendocrine effect; significative differences between the 2 local anesthetics cannot be demonstrated, even if levobupivacaine, which presents a higher anesthetic efficacy, requires lower dosages.

Objective quality assessment of MPEG-2 video streams by using CBP neural networks.

The increasing use of compression standards in broadcasting digital TV has raised the need for established criteria to measure perceived quality. Novel methods must take into account the specific artifacts introduced by digital compression techniques. This paper presents a methodology using circular backpropagation (CBP) neural networks for the objective quality assessment of motion picture expert group (MPEG) video streams. Objective features are continuously extracted from compressed video streams on a frame-by-frame basis; they feed the CBP network estimating the corresponding perceived quality. The resulting adaptive modeling of subjective perception supports a real-time system for monitoring displayed video quality. The overall system mimics perception but does not require an analytical model of the underlying physical phenomenon. The ability to process compressed video streams represents a crucial advantage over existing approaches, as avoiding the decoding process greatly enhances the system's real-time performance. Experimental evidence confirmed the approach validity. The system was tested on real test videos; they included different contents ranging from fiction to sport. The neural model provided a satisfactory, continuous-time approximation for actual scoring curves, which was validated statistically in terms of confidence analysis. As expected, videos with slow-varying contents such as fiction featured the best performances.

Aescin formation in calli and embryoids from cotyledon and stem explants of Aesculus hippocastanum L.

Aescin in calli and embryoids obtained from both cotyledon and stem explants of Aesculus hippocastanum were investigated by HPLC. Determinations were carried out on tissues cultured in agarized medium supplemented with growth substances (2,4-dichlorophenoxyacetic acid; kinetin; 1-naphthaleneacetic acid). The results indicate that aescin was produced in all the analysed samples. The amount of active principle present in some samples was higher than that found in horse-chestnut seeds.

Aescin Content in Embryogenic Callus and in Embryoids from Leaf Explants of Aesculus hippocastanum.

HPLC determinations of the aescin contents in calli and embryoids from leaf explants of AESCULUS HIPPOCASTANUM L. were carried out in order to determine whether it was possible to obtain aescin-forming proliferations IN VITRO. The results indicate that embryogenic calli and embryoids derived from them produce an amount of active principle higher than that of horse-chestnut seeds. The data are discussed in terms of the relation between tissue differentiation and secondary metabolites biosynthesis.

[The action of kinetin on dormant seeds of Cercis siliquastrum. Preliminary observations]. / Azione della chinetina su semi dormienti di Cercis siliquastrum. Prime osservazioni.

Seeds of Cercis siliquastrum L., whose dormancy is broken both by low temperatures and by treatments with gibberellin, were treated with kinetin at various concentrations. This substance does not induce germination, but causes the detaching of the basal portion of the tegument along a circular line without damaging the cells of tegument itself. Such a line is the same as observed in the tegument when the seed naturally germinates.