Search

Aim: The aim of this study was to compare the time course characteristics of cisatracurium (C) and vecuronium (V) induced neuromuscular block (NMB) following multiple doses, allowing spontaneous complete recovery (SCRT) and evaluating the influence of age., Methods: Following institutional approval and signed informed consent, 177 adult ASA 1-2 patients were included in a randomized, double-blind, multicenter study under N20/02/fentanyl/propofol anesthesia. Muscle relaxation was induced with 0.15 mg/kg C or 0.l mg/kg V and was maintained with 0.03 mg/kg of C or 0.02 mg/kg of V injected at T1 25% recovery. Intubating conditions were assessed at 2 min after the initial dose. Time course of NMB was monitored using accelerography (Tofguard) of the adductor pollicis with train-of-four (TOF). Data were analyzed with parametric (Anova) and non parametric statistics (c2, Kruskal Wallis)., Results: Both drugs offered good/excellent intubating conditions: duration of action of NMB (mean values +/- SD, minutes) were: dur25 first dose: V 38.20+/-13.2 vs C 51.5+/-11.3 (P<0.02 ); dur25 following repeated boluses (average): V 23.2+/- 8.6 vs C 28.2+/-9.5, ns; dur25 last dose: V 25.1+/-11.5 vs C 31.5+/-11.4, ns: SCRT following last dose: V 50.2+/-23.2 vs C 46.4+/-17.5, ns: t125% to t4/T1 0.80:V 27.1+/-18.7 vs C 18.8+/-10.2, ns. Stratifying for age >or< 65 no differences were noted in the intervals studied following C, while all were longer following V. The duration of block of C was longer than V; the SCRT after the final dose of C was shorter than V albeit not significant. There was a clinically significant increase in duration of block and recovery time in elderly patients for V but not for C., Conclusions: C and V allow predictable NMB duration and spontaneous recovery even if administered in multiple repeated doses; but in elderly patients duration of block and recovery time is longer following V.

The hyperproduction of oxygen free radicals (OFR) and the weakening of natural scavenging mechanisms are implicated in endothelial damage and in multiple organ failure during septic shock. Many authors have proposed the use of antioxidants to decrease OFR damage. Glutathione (GSH) is one of the most important endogenous antioxidants. It plays the role of a sulphydryl group provider for scavenging reactions. N-Acetylcysteine (NAC) is an artificial precursor of GSH which both increases GSH levels and acts as OFR scavenger. The authors carried out a clinical trial to confirm the capacity of high doses of GSH and NAC to cooperate in reducing lipoperoxidative damage in patients with early septic shock. Patients were divided into three groups who received shock therapy only or shock therapy plus GSH or shock therapy plus GSH plus NAC. OFR damage was evaluated by measuring expired ethane, plasma malondialdehyde, complement activation and clinical scores. The study demonstrated that the group who received GSH and NAC showed a significant decrease in peroxidative indexes and an improvement of the clinical scores if compared with the other two groups. In conclusion the administration of high doses of NAC added to GSH significantly decreases the peroxidative stress of patients with early septic shock.

Background: Numerous publications have analysed the hemodynamic effects of "small volume resuscitation" during the initial phases of hemorrhagic shock. Nevertheless nowadays the information about microcirculatory effects are poor. The aim of this study was to estimate the change of tissue perfusion in hypovolemic rats, before and after infusion of Ringer's lactate (RL), hypertonic saline solution (HS) or blood., Methods: Mesocecal microcirculation was visualized by intravital microscopy during 30 minutes of hemorrhagic hypovolemia (MAP, mean arterial pressure of 40 mmHg) and subsequent reinfusion period. Rats were resuscitated with RL (shed volume), HS (one-seventh of the shed volume), or blood (shed volume). The perfusion was estimated through speed of red blood cells. Moreover MAP, pH and B.E. was measured., Results: Thirty minutes after hemorrhage a very important decrease of capillary flow was noticed and in lesser quantity, of the flow in arterioles and venules. The RL infusion did not cause measureable changes of microcirculatory blood flows. The HS infusion caused an improvement in the flow of arterioles and venules but not in capillaries. The blood infusion caused a progressive improvement in the flow of arterioles, venules and capillaries, however at slightly lower values than previous hemorrhage., Conclusions: Neither RL nor HS seem as efficient as blood to restore the microcirculatory blood flow in the mesocecum of the rats submitted to hemorrhagic hypovolemia.

Background: The so called stop-flow operation is based on locoregional perfusion with an antiblastic hypoxic solution of the region invaded by malignant tissue. Cardiocirculatory complications are common, mainly consisting of reduction of cardiac index, increase of arterial pulmonary pressure, systemic vascular resistance and heart rate. Sevoflurane has been used for its stable hemodynamic profile to reduce cardiocirculatory troubles., Methods: Six patients were submitted to stop-flow operation. General anaesthesia was performed with Sevoflurane 1 MAC in Air/O2. The following parameters were recorded: nitroglycerin infusion m order to maintain the position of the balloon of the catheters, arterial oxygen saturation, end-tidal carbon dioxide, mean arterial pressure, central venous pressure, arterial pulmonary pressure, heart rate and mixed oxygen venous saturation; recordings were performed before stop-flow (T1), during stop-flow (T2) and 10' after reperfusion (T3)., Results: Before stop-flow (T1) all the parameters were normal. At T2 heart rate, cardiac index and pulmonary capillary wedge pressure increased whilst mean arterial pressure, systemic vascular resistance and pulmonary vascular resistance decreased. Ten minutes after the end of perfusion (T3) absence of variations in systemic vascular resistance, in pulmonary vascular resistance, in pulmonary capillary wedge pressure, in cardiac index and in mixed oxygen venous saturation were noticed. Heart rate and central venous pressure showed a tendency to decrease., Conclusions: The hemodynamic profile during stop-flow appears to be stable with general anaesthesia with Sevoflurane.

Background: The aim of this study was to evaluate the discharge rate of children undergoing ophthalmic surgery of medium length (69-120') in a day-hospital regime under general anesthesia with orotracheal intubation and using Sevoflurane as the only anesthetic agent., Experimental Protocol: prospective study., Setting: the study was carried out in the operating theatre of the Ophthalmic Clinic at Florence University., Patients: 58 pediatric patients aged 2-10 years, ASA I-II, 13-34 kg., Operations: correction of strabismus, cataract, glaucoma, palpebral ptosis and intubation of lacrimal tracts. Parameters measure: Any signs of reactivity in the airways to Sevoflurane on induction or reawakening (cough, bronchospasm, laryngospasm and psychomotor agitation), hemodynamic variables (heart rate and NIBP); reawakening time (from turning off the vaporiser to extubation), discharge time from recovery room (SatO2 > or = 97% in ambient atmosphere), discharge time from hospital (stable vital signs, response to simple and complex commands)., Results: The mean reawakening time was 7 min, discharge time from the recovery room was 20 min, discharge time from the hospital 80% after four hours, 100% after six hours. No respiratory and/or cardiovascular complications were reported nor psychomotor agitation., Conclusions: General anesthesia with Sevoflurane and Atracurium was found to be a realistic and reliable technique in pediatric ophthalmic surgery of medium length performed in day hospital.

Background: To compare morphine and tramadol in the treatment of postoperative pain (POP), using a system of Patient Controlled Analgesia (PCA)., Experimental Design: Randomised comparative study on 88 patients, undergoing general major surgical operations (gastrectomy, colectomy and hemicolectomy)., Patients: PCA i.v.: group M treated with morphine (at a dilution of 1 mg/ml) and group T with tramadol (at a dilution of 10 mg/ml). Loading dose: 0.05 mg/kg for the group treated with morphine and 0.5 mg/kg for the group treated with tramadol. Baseline infusion: 1.5 ml/h. Bolus on demand: 0.2 ml every 30 minutes. At T0, after 1 hour, 3 and 18 hours assessment of pain intensity, level of sedation, respiratory and cardiocirculatory parameters. After 18 hours assessment of the amount of drug administered, the number of boluses requested and given and any side effects., Statistical Analysis: ANOVA test, Student "t", chi 2., Results: A statistically significant reduction in POP was found after 1 hour, 3 and 18 hours with no significant differences between the two groups. No statistically significant differences in cardiocirculatory or respiratory parameters or level of sedation were found. Few side effects were observed., Conclusions: Tramadol determines pain relief similar to morphine, with the advantage that it does not lead to abuse, tolerance or addiction.

Background: To compare the postoperative period, with particular regard to occurrence of adverse effects at the time of emergence from anaesthesia, recovery parameters, any post-surgical analgesia requirements and laboratory tests changes in 80 ASA I and II patients undergoing sevoflurane or propofol anaesthesia for elective extracavity surgery., Design: A prospective randomized clinical trial., Methods: Patients were randomly allocated into two groups: in the first group, thiopentone was administered for induction of anaesthesia and sevoflurane for maintenance; the second group received propofol either for induction of anaesthesia and maintenance. All patients received vecuronium for neuromuscular blockade and fentanyl as needed. At the end of surgery, the occurrence of adverse effects, recovery parameters, time of discharge from recovery area, any post-surgical analgesia requirements, time of walking resumption and any laboratory tests changes were recorded., Results: In the sevoflurane group times of discharges from recovery area were significantly faster. In both groups total bilirubin increase was recorded until 72 hours after the end of anaesthesia., Conclusions: Significant differences of postoperative adverse effects and laboratory tests changes were not recorded in both groups of anaesthetics.

Background: Diprifusor TCI is a newly developed target-controlled system for the infusion of propofol. Purpose of this study is to evaluate the acceptability, efficacy and safety of Diprifusor TCI in comparison with the manually controlled technique., Methods: This multicentre, randomised, parallel group study was carried out in 160 patients undergoing surgical procedures of 10 min to 4 h duration in 8 centres. In each centre 20 male or female patients, aged > or = 18 years, ASA I-III were randomised to treatment with either Diprifusor TCI (TCI group--80 patients) or manually controlled infusion (MI group--80 patients). Assessments included hemodynamics; adverse events, including accidents, actual or possible; recovery times; anesthetist ratings of quality of induction and maintenance, and of ease of control and use of technique. Ratings were summed up in a global quality score (study end-point)., Results: Induction doses were significantly lower (median values 1.4 vs 1.9 mg/kg) and maintenance infusion rate significantly higher (median values 10.2 vs 8.8 mg/kg/h) in the TCI group; anesthetists ratings obtained maximum scores in most patients of either group, but more frequently in the TCI group, with significant differences for ease of control (good 91.2% TCI vs 74.7% IM; adequate 8.8 vs 21.5%; poor 0 vs 3.8%), and of use of technique (good 91.2% TCI vs 60.8% IM; adequate 8.8 vs 39.2%); the global quality score showed a significant advantage for the TCI system (median value 12 vs 11)., Conclusions: The TCI technique is effective and safe, and has a better acceptability than the manually controlled infusion technique.

Latex allergy has become a real problem among both surgical staff (paramedics and physicians) and patients especially pediatric patients with urogenital malformations and spina bifida. Latex allergy is produced from both natural molecules which compose the substance produced from Hevea brasiliensis (rubber tree) and industrial additives contents in latex devices. Diagnosis of latex allergy may be carried out through a preoperative Prik-test. A characteristic of latex allergy reaction is the starting of symptoms (more than 15 minutes after allergen contact). Pathophysiology of latex allergy is the same of all allergic reactions; it is an antigen-antibody reaction and type I or II reaction may occur. There are a lot of devices that surgeons and anesthesists use in the operative theatre and that should not be used in presence of a patient with latex allergy. Guaranteed latex-free devices should always be present in store.

Background and Aim: To highlight the intervention sequence of cells and their products (RO degree and NO) involved in the pathogenesis of lung injury caused by the instillation of endotoxin in rats., Experimental Design: An experimental comparative study in rats., Materials and Methods: The experiments were performed using intratracheal instillation of endotoxin in rats (5 mg/kg in 0.125 ml of saline solution). Untreated rats or those instilled with saline solution alone formed the control group. All animals were sacrificed 12, 24 and 48 hours after instillation and the following studies were performed on both lungs: 1) morphological study (optical and electronic); 2) assay of lung MDA; 3) NADPH-diaphorase evaluation using a histochemical method., Results: Lung damage evolves gradually over 48 hours. After the first 12 hours, neutrophil granulocytes were present in the lung capillaries together with monocytes; monocytes were also present in the interstitium. During the following hours, monocytes differentiated into macrophages and, once activated, the granulocytes passed into the interstitium. The parenchyma appears to be extensively altered. Tissular MDA gradually increases until it reaches a maximum level (p < 0.01 vs basal) at 48 hours. Positivity for NADPH-d in macrophage and/or fibroblastic cells was evident after 24 hours and increased after 48 hours., Conclusions: Acute lung injury caused by endotoxin involves both NO and RO degree. Their production is related to different cell types and follows slightly different kinetic.

Background: In the last years the interest for Informed Consent (IC) in anaesthesia has been growing and it has been debated on the adequate explanations in order to obtain a consent. The purpose of the present study was to assess patients' desire for information about anaesthesia., Methods: In this prospective study a form has been given to consecutive patients waiting for surgical operation in general surgery or ear nose throat surgery and able to read and write, to inform them about the necessity of General Anaesthesia (GA); they were asked to complete a questionnaire concerning their desire for information about the following six items concerning anaesthesia: "the duration of anaesthesia"; "what type of pain will I have when I come round, and what pain-killers will I be given"; "details on the various types of anaesthesia, how and where will I be anaesthetized"; "what are the most common complications of general anaesthesia"; "where and how will I come round from general anaesthesia"; "what is artificial respiration in general anaesthesia"., Results: 107 patients participated in the study, 24 of whom were undergoing surgery for malignant cancer and 83 for benign non-oncological diseases. More than two-thirds of patients expressed their wish to receive information, and the trend of desire to know was inversely related to age (p < 0.05). There was no significant statistical difference in the desire to know according either to sex or to the kind of disease (benign or malignant). The demand for information about pain was particularly high (85%), also in the older group of patients. The results and the difficulties for obtaining IC are debated., Conclusions: The growth of patients' desire for information about anaesthesia is an aspect of the evolving doctor-patient relationship in Italy. Efforts should be directed at improving reciprocal communication.

Objective: To evaluate adverse reactions frequency following fluorescein i.v. administration to perform retinoic angiography (ARF)., Design: Retrospective study., Setting: Eye Clinic of the University of Florence., Materials and Methods: 6524 patients undergoing 10,003 ARF. PARAMETERS EVALUATED: For each patient age, sex, concomitant diseases, previous ARF, allergic history and any adverse reaction were evaluated., Results: Adverse experiences were described in 7.5% of 6524 patients. Most of the observed reactions were mild: nausea (3.8%), vomiting (0.43%), vasovagal phenomena (1.18%), anaphylactoid reactions (1.84%). A major rate of adverse reactions were observed in patients previously submitted to ARF who reported in the anamnesis a previous adverse reaction, and in those with a positive allergic history. Severe reactions occurred in 0.27% of patients, but only in 2 of 6524 patients a rianimatory treatment (0.03) was necessary., Conclusion: From the data retrospective analysis it was observed that the manifestation of mild adverse effects was to be expected in many cases. It was therefore possible to point out classes of patients at risk (patients who reported a previous adverse reaction after ARF and patients with positive allergic history). Unfortunately it was not possible to expect and so to prevent the severe effects. Thus it is recommended to perform ARF in an adequately equipped room.

Objective: To compare the cardiovascular effects and recovery characteristics of sevoflurane and propofol anesthesia in 80 ASA I and II patients undergoing elective extracavity surgery expected to last at least one hour., Design: A prospective randomized clinical trial., Methods: After meperidine and atropine premedication, the patients were randomly allocated into two groups: in the sevoflurane group thiopentone was administered for induction of anesthesia and sevoflurane for maintenance; the propofol group received propofol either for induction of anesthesia or maintenance. All patients received N2O, vecuronium, artificial ventilation and fentanyl as needed. Vital parameters were monitored during anesthesia and two hours later. Recovery times were recorded after anesthesia. Statistical analysis was performed with SAS (Statistical Analysis System)., Results: In the sevoflurane group, heart rate and diastolic pressure were slightly higher than in the propofol group. Recovery time was faster after sevoflurane anesthesia.

Background: Several trials have just demonstrated the therapeutic efficacy of gabexate mesylate (Foy). For this drug numerous mechanisms of action have been postulated; protease inhibition, direct or indirect lysosomal membrane stabilization, etc. The aim of this study has been to verify if Foy would express antioxidant properties against free radical overgeneration, responsible for the increase in microvascular permeability which represents one of the most important pathogenetic phenomenon of any condition of shock. A mixture of hypoxanthine-xanthine oxidase has been used to obtain a generation of oxygen free radicals in vivo., Methods: Experiments were performed on the mesocecum of male Wistar rats; fluorescent labelled bovine albumin has been injected intra-arterially to evaluate the capillary permeability and the mesocecum microcirculation has been observed by fluorescent microscopy. The control group received saline i.v., the second group received topically applied on the mesocecum a mixture of 0.96 mM hypoxanthine and 0.05 UI/ml xanthine oxidase; the third and the fourth groups were pretreated respectively with a topical application and continuous infusion of a Foy 1% solution (50 ml/kg/min). To evaluate capillary permeability and to quantify the degree of extravasation by counting the number of leaky sites, labelled bovine albumin was injected i.a. and mesocecum was observed with fluorescent microscopy for 2 hours., Results and Conclusion: Gabexate mesilate (Foy) exerts its efficacy preventing the increase in capillary permeability provoked by an overgeneration of free radicals; it could express antioxidant properties.

Background: A new intubating transilluminated device (Trachlight) has been recently proposed as an alternative to tracheal intubation with direct laryngoscopy., Objective: 1) To evaluate Trachlight device in orotracheal intubation and to assess its operation and complications. 2) To compare the time consumption of transillumination intubation in respect to direct laryngoscopy on the same patients., Methods: The first study was performed on 50 patients undergoing elective surgery and submitted to Trachlight intubation alone; speed of intubation, number of attempts and all complications were recorded and related to Mallampati classes. In the second study 16 patients undergoing to elective surgery were enrolled. Each patient was classified according to both the Mallampati classes and the Cormack classes. Each patient was submitted to two tracheal intubations: the first with the Trachlight and the second with conventional direct laryngoscopy performed by the same anesthesiologist. The time to intubation and the number of attempts were recorded and related to the Mallampati and Cormack classes., Results: In the first study time of intubation with Trachlight was 20.93 +/- 13.02s (mean +/- SD) without statistical differences in respect to the Mallampati classes. In the second study the times to intubation were without any statistical difference independently of the technique of intubation and of the Mallampati or Cormack classes., Conclusions: Orotracheal intubation using Trachlight appears to be an effective and easy to learn technique, being also easy, safe and fast to carry out. The comparison with direct laryngoscopy showed the same speed and effectiveness even on patients with difficult intubation.

Background: The aim of the study is to determine what concentration of ketorolac and morphine administered together i.v. achieve best synergic effect between NSAID antiinflammatory and opioids analgesic properties., Design: Randomized comparative study was carried out on 180 patients, ASA II-IV, undergoing major general surgery, in an University Clinic., Methods: Postoperative pain therapy by i.v. PCA: group 1 morphine 0.75 mg.ml + ketorolac 0.75 mg.ml; group 2 morphine 0.50 mg.ml + ketorolac 1.50 mg.ml; group 3 morphine 0.25 mg.ml + ketorolac 1.50 mg.ml; in saline solution. Initial bolus: 2 ml. Continuous infusion 1.5 ml.h. Demand bolus: 0.2 ml. Lockout time: 30 minutes. Evaluations included: pain intensity (T0, T3, T18); total amount of infused drugs (T18); number of valid demands and attempts (T18); amount of autoadministered analgesic drugs in percent of highest available amount (T18); side effects (T18); patient's judgment., Data Analysis: ANOVA and Student's "t"-test., Results: A statistically significant reduction of pain intensity was found after 3 and 18 hours in the three groups, no differences were found among the groups. Group 2 required an amount of autoadministered drugs significantly lower than other groups. Rare side effects. Patient's judgment was generally positive., Conclusions: Results suggest a greater synergetic effect between morphine and ketorolac in concentrations used in group 2.

Background: Circulatory shock, especially endotoxin shock, is characterized by the release of a large number of mediators, among which proteases play a key role. The production of oxygen free radicals into the extracellular space and the increase of capillary permeability is one of the most important consequences of that phenomenon. In order to evaluate the efficacy of gabexate mesilate (Foy) in preventing such increase of microvascular permeability, an experimental model of endotoxin shock was used., Materials and Methods: Experiments were performed on the mesocecum of male Wistars rats, fluorescent labeled bovine albumine was injected intrarterially to evaluate the capillary permeability and the mesocecum microcirculation was observed by fluorescent light. The control group received saline i.v.; the II group received a DL 100 of E. coli endotoxin (DIFCO 0111: B4); the III and the IV group received a continuous infusion or topical application of gabexate mesilate respectively, before the administration of endotoxin. To evaluate capillary permeability and to quantify the degree of extravasion by counting the number of leaky sites, fluorescent labelled bovine albumin was injected i.v. and mesocecum was observed with fluorescent microscopy for 2 hours., Results and Conclusions: Capillary permeability did not increase in control rats; it largely increased in rats receiving endotoxin i.v. but it did not almost increased in rats receiving gabexate mesilate (Foy) that prevents the increase of capillary permeability that was observed in the group treated with endotoxin alone.

The authors report two cases of unexpected nitrogen accumulation in the circuit during low flow anaesthesia with a fresh gas flow of 600 ml/min (O2:N2O = 1.1). Though the presence in the anaesthesia circuit of nitrogen eliminated by the patient is a common feature of closed circuit and low flow techniques, the magnitude and the speed of increase of inert gas concentration (compared with data from previous experiences) were highly suspicious for an external source. This was readily identified as a "mini" leak (30 ml/min of N2) from the air flowmeter, although his valve was in fully closed position. The report depicts an uncommon cause of air entry in the anaesthesia circuit and confirms the need for monitoring gases and vapours when closed circuit and low flow techniques are employed.

Background: Succinylcholine is contraindicated in "open eye" surgery because it raises intraocular pressure. High dose vecuronium reduces onset time for orothracheal intubation. The objective of the study was to evaluate clinical efficacy of high dose vecuronium (0.2 and 0.3 mg/kg) and its effects on intraocular pressure for its use in "open eye" emergency surgery., Design: Randomized, prospective, clinical trial., Setting: Eye clinic of University of Florence., Patients: 40 patients scheduled for vitrectomy, excluding any drug action on IOP, subdivided into two groups: the first (20 patients) had 0.2 mg/kg vecuronium at the induction of anaesthesia, the second (20 patients) 0.3 mg/kg. ANAESTHESIA: Premedication: atropine 0.01 mg/kg. Preinduction: fentanyl 3 micrograms/kg. Induction: thiopentone 4 mg/kg+ after 1 minute) vecuronium. Orotracheal intubation after 90"., Measures: IOP was obtained by applanation tonometry in three time: T0 = preinduction; T1 = 50" after thiopentone; T2 = 50" after vecuronium. Systodiatolic pressure was obtained at the same time. Neuromuscular function was evaluated by vocals cord relaxation and by clinical evaluation of response to ulnar nerve stimulation (by train of four)., Statistic: "t"-Student., Main Results and Conclusions: No modification of IOP and systodiastolic pressure was caused by administration of vecuronium; no statistic differences are between T1 and T2 values. All patients were intubated after 90" vecuronium administration; the vocal cord relaxation was maxima in all the patients. High dose vecuronium seems to be useful in "open eye" emergency surgery when succinylcholine is contraindicated.

Background: Anaesthesia drugs cause the cutaneous vasodilatation that produces core temperature lowering at the beginning of general anaesthesia; when the thermal threshold for vasoconstriction is reached the cutaneous heat losses are decreased. Furthermore, the soda lime begins to produce water and heat after 40 minutes of closed circuit ventilation. WORK HYPOTHESIS: The technique of inhalatory anaesthesia affects the thermal loss of patients after some hours of ventilation., Design: Prospective randomized clinical trial., Setting: Surgical Clinical operating theatre of the University of Florence., Patients: 50 patients submited to abdominal non vascular surgery, for longer than 2 hours, with xifo-pubic cut, subdivided into two groups with the same anthropometric characters and age; the first ventilated with open system, the second with low flow circuit (fresh gas flow 700 ml/min)., Statistic: "t" Student test;, Measures: Lower one third oesophageal and inspiratory jaw of the circuit temperatures recorded for three hours., Main Results: The savings of low flow anaesthesia begin to be significant in the third hour of anaesthesia., Conclusions: The thermal saving of closed circuit anaesthesia is, very probably, related to the humidifying and the warming of inspired air by soda lime reaction; the effect is more evident if cutaneous losses are reduced.

Objective: To evaluate whether volume replacement with gelatine infusion with 3.5% urea bridges during normovolemic intentional hemodilution manages to stabilize hemodynamic parameters., Experimental Design: Randomized prospective study., Setting: Operating theatre for general surgery., Patients: ASA 1 and 2 patients undergoing major abdominal surgery. Criteria of admission: a) age < 70 years old; b) starting hematocrit > 30%; c) absence of coronary diseases or coagulative pathologies., Interventions: Blood lost during surgery was replaced with gelatine and crystalloid in a ratio of 1:1. Hemodynamic monitoring was performed by inserting an Opticath catheter in the pulmonary artery and the resulting data were processed using an Oximetrix computer., Findings: Oxygen transport (DO2), oxygen consumption (VO2) and heart rate (HR) were measured before the start of the operation and at the peak of hemodilution., Results: At times T0 = Hct 35 and T1 = Hct 28, studied parameters (DO2, VO2, HR) did not show statistically significant variations., Conclusions: On the basis of the hemodynamic parameters studied gelatine was found to be an efficacious volume replacement solution during the course of moderate, intentional hemodilution.

Background: Reduced Glutathione (GSH) is a well known physiological antioxidant, that would protect against lethal effects of endotoxin. However, the site of the action of GSH can be intracellular (transmembrane passage of constitutive amino acids) or extracellular (membrane thiols)., Aim of the Work: To search if L-cysteine (one of three constitutive amino acids of GSH) protects against endotoxin as GSH and to search if inhibition of transmembrane passage of GSH and L-cysteine by Probenecid affects that protection., Materials and Methods: Rats injected (n = 99) with a lethal dose of endotoxin (BACTO, DIFCO lab. 0111:B4 10 mg/kg ip) immediately after received: (a) Saline solution; (b) GSH 500 mg/kg; (c) L-Cysteine 0.25 g/kg; (d) Probenecid 25 mg/kg in 20% Ethanol plus GSH 500 mg/kg; (e) Probenecid 25 mg/kg in 20% Ethanol; (f) 20% Ethanol. The administration of Saline solution, GSH, L-cysteine was repeated two hours later. Injection volume was 0.5 ml ip. Survival rate of each group of rats was evaluated 6, 12 and 24 hours after endotoxin injection. Survival was compared with that of the control group by Fisher test., Results: GSH and L-cysteine significantly increase survival if compared to all other treatments (respectively p < 0.002 and p < 0.001 at 12 hours; p < 0.005 and p < 0.0002 at 24 hours). Probenecid nullifies the survival increase caused by GSH. Probenecid alone or Ethanol alone show a survival rate not significantly different in respect to control group., Conclusions: Protection exerted by GSH against fatal effects of endotoxin is also provided by one of its constituent amino acids (L-cysteine) and is inhibited by Probenecid. So we can infer that such an antioxidant action happens at an intracellular site. Need of high doses of GSH and L-cysteine can be due to the necessity of a strong concentration gradient between extra and intracellular sites.

Unlabelled: BACKGROUND AND WORK HYPOTHESIS: The mechanisms of organ damage in MODS are unclear. Given that lipid peroxidation induced by oxygen radicals may play a key role in organ damage, expired ethane, a marker of lipid peroxidation, could be correlated to the entity and evolution of experimental MODS., Study Design and Methods: Forty wistar male rats (250 +/- 15 g body weight) were intraperitoneally injected with 10 ml of Zymosan mineral oil suspension (2.5%) to provoke MODS. Survival and symptoms were noted daily. On the 2nd, 7th and 14th day the animals underwent thorax CT scanning. CT images were processed to evaluate the relative density of lung parenchima. Expired ethane was measured using mass spectrometer and percentual changes were noted. Relative organ weight (liver and lung) were measured in 2nd, 7th and 14th day., Statistical Analysis: Pearson's linear correlation., Results: The results show that maximal lung damage took place at the same moments as ethane concentrations peaked. A strict correlation (r = 0.93; p < 0.0001) was found between lung density and expired ethane. Strict correlation was found between organ weight, symptoms, survival and ethane production., Conclusions: Lipid peroxidation, as expressed by ethane production, might be an important cause of organ damage in MODS.

Background: The aim of this study is to control the depth, the quality of recovery of total inhalation isoflurane anesthesia with or without nitrous oxide., Design: Controlled comparative study was carried out on 51 patients, aged 40-54 yr, ASA 1, undergoing saphenectomy, in an University Clinic., Methods: Induction: thiopental (3.5 mg kg), atracurium (0.6 mg kg) i.v. Patients were randomly assigned to: group 1 (26 patients), 5% isoflurane in air, by mask; group 2 (25 patients), 3% isoflurane and 60% N2O, by mask. Maintenance: group 1, 2% isoflurane in air; group 2, 1.2% isoflurane and 60% N2O. During anesthesia, consciousness and analgesia level were monitored by EEG Compressed Spectral Array, and clinical signs of pain by Evans' test; arousal time evaluation by "Time to correct response test". The subjective impressions, eventual dreams and recalls were collected using a standard set of questions one hour after the end of anesthesia and 24 hours later. One hour before anesthesia and two hours after the end of surgical procedures, a psychomotor performance recovery evaluation was performed using Zazzo's "deux barrages" test., Data Analysis: Student's "t" test., Results: Adequate anesthetic depth was documented in all patients. Recovery time was statistically longer in isoflurane group (group 1 16.7 sd 2.2 minutes vs 10.3 sd 1.9 minutes group 2, p < 0.01). No patient reported recalls relative to anesthetic period. Two hours after recovery no significant differences in psychomotor performance tests were recorded., Conclusions: Isoflurane anesthesia in air, in adequate concentrations, provides a sufficient level of analgesia, hypnosis, amnesia, without clinical side effects.

Abdominal aortic surgery has significant effects on cardiac and splanchnic perfusion. The purpose of this study was to examine the effects of dopexamine, an inodilator drug, on hemodynamic and splanchnic perfusion with measurement of gastric intramucosal pH, by the method of gastric tonometry, during abdominal aneurysm resection. Twenty-five patients undergoing excision of an aortic abdominal aneurysm were randomly divided into two groups. During aortic cross-clamping Group II patients received dopexamine infusion, at a dose of 1 microgram/kg/m, and at a dose of 0.5 micrograms/kg/m from declamping to the end of the surgery. Whereas Group I patients did not receive a dopexamine infusion. During aortic cross-clamping the intramucosal pH value decreased in Group I patients, but did not change in Group II patients. Heart rate, cardiac index, and mixed venous oxygen saturation increased significantly during dopexamine infusion, whereas systemic vascular resistance was reduced. During aortic cross-clamping dopexamine was a useful agent in improving splanchnic blood flow, cardiac index venous saturation. Also, since the drug produces dose related hemodynamic changes of rapid onset and reversibility, it is possible to interrupt the infusion before aortic declamping to avoid the decrease in the intramucosal pH value.

Objective: To perform an experimental model of Multiple Organ Dysfunction Syndrome (MODS) without employing bacteria or endotoxin stimulus and to follow its evolution in vivo by a Computerized Tomography analysis of the lungs., Design: Rats were submitted to intraperitoneal injection of a 2.5% zymosan suspension in mineral oil (1 g/kg weight) or mineral oil alone; control rats received no treatment., Methods: The observation period was 15 days. During this period symptoms and survival were noticed daily. CT scans of lungs were made at the 7th and 14th days; data were post-processed to obtain information on lung density. The rats were sacrificed at the 15th day by heart puncture; blood was utilized for determination of hemochrome, differential leukocyte count, thrombocytes, glycemia, uremia, bilirubin. Lungs, liver, spleen and kidney were dissected and weighted for determination of relative organ weight., Data Analysis: Data were compared by "t" Student's test for impaired data and Fisher Exact test., Results: Symptoms, survival, blood analysis and relative organ weight agreed with a progressive, ingravescent, triphasic illness caused by a systemic inflammatory response involving remote organ too. The CT study proved able to monitoring and analyzing organ damage: a temporal sequence of evolution of damage exists; organ damage is localized in microcirculatory system (density augment) and in parenchyma (morphologic alterations and fibrosis)., Discussion: The described experimental model reproduces a MODS-like illness in zymosan receiving rats; the CT scan is effective to evaluate the evolution of organ damage.

Objective: The reflex response to orotracheal intubation provokes an increase of arterial pressure accompanied by an increase of chorioides volume and a consequent ocular hypertone. There are several methods to reduce the reflex response due to intubation. One of the most effective is topical anaesthesia of larynx and trachea. Experiments were directed to evaluate the efficacy of topical anaesthesia to reduce the intraocular hypertone due to orotracheal intubation., Design: A prospective randomized mask study was conduct on patients undergoing ophthalmologic (anterior segment) surgery at the Eye Clinic of Florence University., Methods: Intraocular pressure was measured by a Goldman tonometer at four times: T0 = basal, T1 = 2' minutes after induction of general anaesthesia, T2 = 2' minutes after laryngoscopy, T3 = 2' minutes after orotracheal intubation. At the same moments, systolic blood pressure, heart rate, rate pressure pro duct were measured. Patients were randomly divided in two groups: Group L (n = 10) in which was evaluated the efficacy of laryngotracheal topical spray of lidocaine 4% (2 ml) and Group F (n = 10) in which saline was used instead of anesthetic. The filling of the LTA kit (Abbott) was made by a person not involved in the experiments., Data Analysis: Student's t test for unpaired data., Results: Topical anaesthesia reduces the increase of intraocular pressure, hypertension and rate pressure product due to intubation. The intraocular pressure reduces to 13% less than basal value in Group L and increase to 50% more than basal value in Group F., Conclusion: The topical anaesthesia of larynx and trachea is effective to reduce the intraocular hypertension due to the reflex response evoked by orotracheal intubation.

Two cases of dextran-induced anaphylactoid reaction (grade II and III according to Ring e Messmer) are reported. Metabolic acidosis was an early symptom that must be considered on planning immediate therapy.

Objective: To determine whether a non lethal dose of intramuscular endotoxin in rats causes a physical disruption of the mucosal barrier and promotes the translocation of bacteria from gut to visceral organs., Design: Prospective randomized trial., Setting: Experimental laboratory university medical center., Experiments: 60 male wistar rats, weighing 250 g., Interventions: six hours and twenty-four hours after endotoxin (8 mg/kg) or saline (control group) given intramuscularly, rats were sacrificed and mesenteric lymph nodes, spleen and some segments of the ileum were removed. Lymph nodes and spleen were cultured for translocating bacteria while ileum segments were observed by light microscopy., Results: Incidence of bacterial translocation increases from 6 hours (40% p < 0.05) to 24 hours (60%, p < 0.01) after endotoxin administration. Histologic evaluation of the ileum demonstrated that a mucosal injury occurred only at the 24 an hour and that it was characterized by an evident pronounced interstitial edema with focal breaks in the basal membranes of villous and glands., Conclusions: It appears that microorganisms and microbial products contained in the gut can cross the mucosal barrier and spread into other visceral organs also after a low dose of intramuscular endotoxin.

The Emergency Medical System (EMS) in the district of Florence is based upon the activity of 13 Emergency Mobile Unit (EMU). The activity of such a huge system is difficult to evaluate: we have concentrated our attention upon the diagnostic process assuming that "correct diagnosis = correct treatment = benefit for the patient". Then we compared diagnoses set on EMU to diagnoses made in hospitals, giving to each comparison a score from 1 to 5. In terms of quality the services of the EMS in Florence seem to be effective, since in 72% of cases the Hospital Emergency Department has confirmed the diagnoses achieved under emergency conditions, and in 12% only there has been remarkable difference. Comparing the diagnoses made on EMU to that at the hospital discharge, in two thirds of cases there is excellent correlation.

Endotoxin administration increases capillary permeability in experimental animals and this is one of the most relevant events in the pathophysiology of endotoxin shock; the aim of the present experiment was to demonstrate that the action of endotoxin on capillary permeability is due to oxygen-free radicals generation. Experiments were performed on the mesocecum of male Wistar rats; fluorescent labeled bovine albumin (FITC-BSA) was injected intra-arterially to evaluate the capillary permeability; the mesocecum microcirculation was observed by fluorescent light. Permeability was quantified by changes in the number of leaky sites at 10 minute intervals for an hour. The effects of Endotoxin (DIFCO 0111:B4, 30 mg/kg i.a.) were assessed in rats receiving 1) saline, 2) reduced glutathione (250 or 500 mg/kg i.p.), 3) three different nitrones (PBN, DMPO, POBN) (6.25 mg/kg i.p.) whose action is to "trap" oxygen radicals. Capillary permeability largely increased in a few minutes in control rats but it was quite unaffected in rats receiving glutathione or nitrones. As a conclusion the increased capillary permeability observed after endotoxin injection in rats may be due to an oxygen-radicals generation.

Background: Circulatory shock has been accepted as a consequence of a chain of biochemical events beginning with production of proteases and ending with an uncontrolled generation of oxygen radicals., Objective: To evaluate the efficacy of gabexate-mesilate (FOY) in circulatory shock in man. Gabexate-mesilate is a new wide-range synthetic protease inhibitor that also has antioxidant properties., Design: Clinical multicenter study with open design that has been compared with some Japanese controlled studies performed using identical parameters and very similar protocols., Experiments: 59 shocked patients were treated with FOY in 9 italian intensive therapy units. Circulatory shock was traumatic (n = 14), traumatic-hemorrhagic (n = 25), septic (n = 11) or of mixed type (n = 9). Evaluation of seriousness of shock on beginning of therapy and during the follow-up period was performed on the basis of the same "shock score" (Ogawa and Fujita, Jap J Surg 12:122, 1982) that was used in Japanese clinical studies on FOY in shock. 1.45 mg/kg/hour of FOY were injected i.v. during 48 hours. Conventional therapy was permitted but steroids and aprotinin were excluded. The follow-up period was 9 days., Results: 8 patients died. The mean initial score of the survivors was 8.2; after 8 hours it was 5.0 and after 12 it was 4.0. No adverse reactions were reported. The above quoted survival was greater than that of Japanese studies although the initial score was quite the same. However these studies were controlled and demonstrated gabexate-mesilate to be significantly more active in shock therapy than placebo. They also demonstrated an activity of FOY greater than that of aprotinin when shock was associated to acute respiratory insufficiency and to coagulopathies., Conclusions: Gabexate mesilate might be useful in therapy of circulatory shock due to its wide-range inhibition of proteases and to its antioxidant properties.

Normovolemic hemodilution at two different hematocrit values was performed in ten patients undergoing major surgery to evaluate changes of DO2, VO2 and CI. A Hct of 38% (low hemodilution) was reached by plasma replacement with ringer lactate infusion. A further hemodilution, a Hct of 30% (high hemodilution), was obtained by hydroxyethyl starch plus ringer lactate (1:2 ratio) infusion. A significant VO2 increase (p less than 0.01) occurred when hydroxyethyl starch plus ringer lactate infusions were employed as compared to ringer lactate alone. No changes in DO2 and CI were observed, the increase in VO2 measured during colloid infusion could suggest a better tissue perfusion and metabolic activity.

Closed circuit and low flow anaesthesia offer numerous advantages such as reduction of gas consumption, low cost, and less pollution in both the operating theatre and the environment. These procedures also offer increases in inspired gas humidity and temperature. However the time needed to attain the alveolar concentration MAC 95, is too long. Prefilling the whole circuit, the bellow and the bag with anaesthetic vapours shortens that time without overdosage.

Closed circuit anaesthesia (CCA) and minimal flow anaesthesia diminish inhalatory anaesthetic consumption. Consumption of inhalatory anaesthesia was calculated using two different techniques: CCA and "non rebreathing" system. Costs were compared on the basis of the official list price. The CCA allowed for reduced consumption at lower costs. The resulting annual savings are equal to one third of the total price of the whole apparatus with its complementary monitoring and control systems.

This study was conducted on 10 patients with primitive or metastatic liver tumors, scheduled for massive liver resections, in order to search for evidence of the existence of intraoperative prognostic indexes having a bearing upon postoperative survival. The following parameters were measured in every patient: HR, MAP, CVP, MPAP, WP, SVR, PVR, CI, DO2, VO2, BE, before the anhepatic period (A), during anhepatic period (B), 30' (C), and 60' (D) after liver reperfusion, holding constant Hct, body temperature, ETCO2, FiO2, anesthetic depth, and the degree of muscular relaxation. The patients were later divided into two groups: 1, nonsurvivors in the postoperative period (4 patients) due to MOF; 2, survivors (6 patients). The values of the measured parameters of the two groups were statistically evaluated at each of the above intervals, and within each group with respect to time A, taken as a control. No significant variations were found in HR, MAP, CVP, MPAP, WP, SVR, PVR, CI, and DO2. The VO2 diminished in both groups during the anhepatic period (B) (p less than 0.0025). In group 1 (nonsurvivors) the VO2 diminished after the reperfusion (p less than 0.0025), while in group 2 (survivors) VO2 rapidly resumed its initial values (n.s. 30' and 60' after the reperfusion). In the nonsurviving patients metabolic acidosis developed, with significant reductions of BE (p less than 0.0025) during times C and D, occurring simultaneously with the reduction of VO2.(ABSTRACT TRUNCATED AT 250 WORDS)