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F Carli

Publications and source records attributed to F Carli.

At least 55 records · Page 3Linked to original sources
PubMed1999

The independent effect of propofol anesthesia on whole body protein metabolism in humans.

BACKGROUND: The purpose of this study was to examine the effect of general anesthesia with propofol in the absence of surgical stimulation on whole body protein metabolism. METHODS: Six unpremedicated patients were studied. General anesthesia included propofol (120 microg x kg(-1) x min(-1)), vecuronium bromide, and oxygen-enriched air. Changes in protein breakdown, protein oxidation, and synthesis were measured by an isotope dilution technique using a constant infusion of the stable isotope tracer L-[1-13C]leucine (0.008 mg x kg(-1) x min(-1)) before and during 100 min of propofol anesthesia. The plasma concentrations of glucose, lactate, non-esterified fatty acids, and cortisol were measured before and during anesthesia. RESULTS: An isotopic steady state of plasma [1-13C]alpha-ketoisocaproate (taken to represent the intracellular leucine precursor pool enrichment for protein synthesis) and expired 13C-carbon dioxide were obtained before and during propofol infusion. Whole body protein breakdown decreased during propofol anesthesia by 6% (P < 0.05), whereas protein synthesis and oxidation did not change significantly. Plasma concentration of cortisol decreased after 90 min of propofol anesthesia (P < 0.05). No significant changes of plasma concentrations of glucose, lactate, and non-esterified fatty acids occurred during propofol administration. CONCLUSIONS: Propofol anesthesia did not significantly affect whole body protein synthesis and oxidation but caused a small, although significant, decrease in whole body protein breakdown, possibly mediated through the suppression of plasma cortisol concentration.

Adult↗
PubMed1998

Sentinel lymph node mapping opens a new perspective in the surgical management of early-stage breast cancer: a combined approach with vital blue dye lymphatic mapping and radioguided surgery.

Recent studies have demonstrated the possibility of identifying the sentinel lymph node (sN) as a reliable predictor of axillary lymph node status in both cutaneous melanoma and breast cancer. However, some important issues need further definition: (1) optimization of the technique for intraoperative detection of the sN; (2) predictive value of the sN as regards axillary lymph node status, and (3) reliability of intraoperative histology of the sN. We report our experience in sN mapping in patients with Stage I-II breast cancer, with the aim of assessing: (1) the feasibility of lymphatic mapping with a combined approach (vital blue dye lymphatic mapping and radioguided surgery); (2) the agreement of the intraoperative histologic examination of the sN, by means of hematoxylin and eosin staining with final histology, and (3) the accuracy of sN histology as a predictor of axillary lymph node status.

Aged↗
PubMed1998

Epidural analgesia in early labour blocks the stress response but uterine contractions remain unchanged.

PURPOSE: To determine the effect of epidural analgesia on biochemical markers of stress, plasma oxytocin concentrations and frequency of uterine contractions during the first stage of labour. METHODS: Nine nulliparous women, in spontaneous labour, with a singleton fetus and cervical dilatation < or = 5 cm were enrolled. Epidural bupivacaine 0.25% (range 10-14 ml) was administered and bilateral sensory blockade to ice (T8-L4) achieved. Blood samples were collected before the epidermal block and every 10 min for one hour after the block was achieved for the measurement of plasma beta-endorphin, cortical, glucose, lactate and oxytocin concentrations. No exogenous oxytocin was given. Intensity of pain was assessed at the time of the blood sampling using a 10 cm visual analogue scale (VAS). The frequency of uterine contractions was recorded for 60 min before and after the epidural block. RESULTS: There was a decrease in plasma beta-endorphin and cortisol concentrations after epidural block (P < 0.01). There were no changes in plasma glucose and lactate concentrations. The mean VAS for pain decreased 10 min after epidural block was achieved and remained < 2 throughout the study period (P < 0.001). Mean plasma oxytocin concentrations did not change. The frequency of uterine contractions before and after the epidural block was similar. CONCLUSIONS: The metabolic stress response to the pain of labour was attenuated by epidural analgesia. In contrast, plasma oxytocin concentration and frequency of uterine contractions were unaffected by the attenuation of metabolic stress response.

Adult↗
PubMed1998

Metabolic changes during recovery in normothermic versus hypothermic patients undergoing surgery and receiving general anesthesia and epidural local anesthetic agents.

BACKGROUND: Mild hypothermia is accompanied by metabolic changes. Epidural local anesthetic agents attenuate the surgical stress response, but it is not known whether they modulate thermal stress. METHODS: Thirty patients undergoing colorectal surgery, performed by one surgical team, received epidural 0.5% bupivacaine to achieve T3-S5 sensory block. They were then assigned randomly to two groups of 15 patients each. The control or unwarmed group was left to cool during surgery, whereas active warming was used in the warmed group. General anesthesia was induced by thiopentone, vecuronium, fentanyl, nitrous oxide in oxygen, and enflurane. At the end of surgery, both groups received epidural 0.25% bupivacaine to maintain a T5-L3 sensory block. Aural canal (core) and skin surface (15 sites) temperatures; oxygen consumption; pain visual analogue score; and concentrations of epinephrine, norepinephrine, glucose, cortisol, lactate, and free fatty acids in plasma were measured before epidural blockade, 30 min after epidural blockade, at the end of surgery, and for 4 h after surgery. Patients and those measuring the outcomes were unaware of group allocation. RESULTS: Core and mean skin temperatures decreased significantly in the control group (P < 0.001) but not in the warmed group. Catecholamine concentrations in plasma decreased significantly after epidural block, and although concentration of epinephrine in plasma increased from baseline sharply in the control group at the end of surgery (P = 0.004), it decreased in the warmed group (P = 0.007). During recovery, there was no difference between the two groups for norepinephrine concentrations in plasma, body weight-adjusted oxygen consumption, pain visual analogue score, and metabolites. CONCLUSIONS: The postoperative metabolic changes obtained with epidural block were similar except for an attenuated concentration of epinephrine in normothermic patients compared with those who were mildly hypothermic.

Aged↗
PubMed1997

A nitrogen-free hypocaloric diet and recombinant human growth hormone stimulate postoperative protein synthesis: fasted and fed leucine kinetics in the surgical patient.

Twelve otherwise healthy patients undergoing elective surgery for resection of rectosigmoid adenocarcinoma were randomly allocated to two groups: one group receiving intravenous dextrose 5% 600 to 800 kcal.d-1 (DX, n = 6) and the other group receiving the same amount of dextrose intravenously plus recombinant human growth hormone (DX + rGH, n = 6). Supplementation with rGH started on the day of surgery and continued postoperatively for 5 days. No nitrogen was provided in the diet. This regimen was started 3 days before surgery and continued for 5 days after surgery. Protein kinetics were studied over a period of 8 hours in all patients. Following an overnight fast, a primed constant infusion of L-[1-13C]leucine was maintained for 4 hours (fasted state) and continued for a further 4 hours (fed state) during which 5% beet dextrose (low 13C content) with or without rGH was administered. The isotope studies were performed on the day before surgery and 6 days after surgery. Other measurements included urinary nitrogen excretion, gaseous exchange, and plasma concentrations of insulin, GH, and insulin-like growth factor-I (IGF-I). Addition of rGH to the dextrose diet had a significant positive effect on protein synthesis (P = .02). Surgery was responsible for a significant increase in postoperative whole-body protein breakdown and synthesis and leucine oxidation (P < .01), although lesser changes were observed in the DX group. An interaction between rGH and surgery was associated with a significant increase in protein synthesis (P = .009), but not with changes in either protein breakdown or leucine oxidation. Carbohydrate provision in the form of beet dextrose during the fed state of the isotopic study did not attenuate the significant decrease in protein synthesis (P = .01) or breakdown (P = .003) either before or after surgery, probably reflecting the absence of nitrogen in the diet. No significant interaction was found between rGH and feeding. These results of leucine kinetics indicate that addition of rGH to a low-dextrose intake in the absence of dietary nitrogen can actually promote protein synthesis. The low levels of leucine oxidation could be explained by the fact that amino acids resulting from protein degradation were directed preferentially toward resynthesis of new proteins rather than to oxidative pathways. There was a significant increase in plasma insulin and GH in the group receiving rGH (P < .05). The postoperative plasma concentration of IGF-I did not change in the latter group compared with the DX group, in which IGF-I concentration decreased significantly (P < .05) as part of the response to combined surgery and dietary restriction. Although both IGF-I and insulin are independently capable of stimulating protein synthesis, elevated levels of either hormone or GH itself may primarily modulate protein synthesis, even with a low intake of carbohydrates.

Adenocarcinoma↗
PubMed1997

Growth hormone modulates amino acid oxidation in the surgical patient: leucine kinetics during the fasted and fed state using moderate nitrogenous and caloric diet and recombinant human growth hormone.

Twelve patients (aged 70 +/- 9 years) who were scheduled for resection of rectosigmoid colon adenocarcinoma but were otherwise healthy were randomly allocated after surgery to receive either peripheral parenteral nutrition alone ([PPN] n = 6) or in combination with recombinant human growth hormone (rGH) at a daily dose of 0.15 U x kg(-1) x d(-1)(PPN + rGH, n = 6). The daily nutritional regimen was 0.1 g nitrogen x kg(-1) x d(-1) and 20 kcal x kg(-1) x d(-1) (nonprotein energy was supplied as 60% lipid and 40% carbohydrate), and it was maintained for 6 days before and 6 days after surgery. Protein kinetics were studied in all 12 patients during the fasted and fed states before and 6 days after surgery using an 8-hour 13C-leucine tracer infusion. Daily urinary nitrogen, gaseous exchange, and plasma insulin, growth hormone, and insulin-like growth factor-I (IGF-I) were determined before and after surgery. Surgery was responsible for significant increases in postabsorptive whole-body protein flux and synthesis and leucine oxidation (P < .01). Supplementation of PPN with rGH contributed to a significant attenuation of the postoperative increase in leucine oxidation (P = .02), with a significant increase in whole-body protein synthesis (P = .02) and no effect on protein breakdown (P = .40). During the fed state, leucine oxidation increased significantly (P = .005), with the greatest change occurring in the PPN group. Feeding was associated with a significant decrease in whole-body protein breakdown before and after surgery in both groups (P = .001). Postoperative urinary nitrogen excretion was lower but was not statistically significant in the PPN + rGH group compared with the PPN group. There was a significant increase in oxygen consumption (VO2) and carbon dioxide production (VCO2) as a result of feeding and surgery (P < .01). Supplementation with rGH caused a decrease in the respiratory quotient (RQ) (P = .04), particularly after surgery, indicating a direct effect of rGH on fatty acid oxidation. Circulating plasma insulin increased significantly in both groups with feeding and rGH supplementation (P < .05). This was enhanced after surgery, particularly in the rGH group (P < .05). Plasma growth hormone decreased after surgery in the PPN group (P < .05), but did not change as a result of feeding. The circulating levels increased in the PPN + rGH group following subcutaneous administration before or after surgery. Plasma IGF-I decreased after surgery in the PPN group (P < .05), and no changes occurred in the PPN + rGH group with feeding. The present findings suggest a distinct positive effect of rGH on protein synthesis in catabolic patients receiving a moderate intake of nitrogen and calories. This is achieved by modulation of amino acid oxidation. The acute effect of intravenous (IV) nutrients on protein metabolism during the catabolic phase of surgical stress caused a direct decrease in protein breakdown with no effect on protein synthesis.

Adenocarcinoma↗
PubMed1997

Continuous epidural blockade arrests the postoperative decrease in muscle protein fractional synthetic rate in surgical patients.

BACKGROUND: Epidural anesthesia with local anesthetics is associated with postoperative attenuation of nitrogen loss. The protein-sparing effect could be the result of either a decreased protein breakdown or increased protein synthesis. Although the role of epidural local anesthetics in effectively limiting the increase in postoperative protein breakdown is established at the whole-body level, it is necessary to determine whether the muscle protein fractional synthetic rate is directly modulated when nociceptive stimuli are blocked. METHODS: Twelve otherwise healthy patients scheduled for elective colorectal surgery, who were receiving a constant intake of nitrogen (0.1 kg-1.day-1) and calories (20 kcal.kg-1.day-1) before and after surgery, were randomly assigned to receive either general anesthesia (with thiopentone, vecuronium, fentanyl, or enflurane; control group, n = 6) or epidural anesthesia (T3-S5 sensory block with 0.75% bupivacaine) and general anesthesia (epidural group, n = 6). In the control group, postoperative analgesia was achieved with papaveretum given subcutaneously, whereas a continuous epidural bupivacaine infusion (T8-L5 sensory block) was maintained for 48 h in the epidural group. The postabsorptive muscle protein fractional synthetic rate was determined using a 6-h continuous infusion of 13C-labeled leucine (1 mg.kg-1.h-1), and the 13C enrichment in muscle biopsy specimens before surgery and 48 h after surgery was measured. RESULTS: Plateau 13C enrichment of plasma alpha-ketoisocaproate (taken to represent the intracellular leucine precursor pool enrichment for protein synthesis) was achieved during the 6-h infusion (mean coefficient of variation was 2.8%). Muscle protein synthesis at 48 h after operation compared with preoperative levels decreased significantly in the control group (P = 0.03). In contrast, it increased by 25% in the epidural group. Although this was not significantly (P = 0.15) different from preoperative levels, it was significantly greater than in the control patients. CONCLUSIONS: Epidural infusion of local anesthetics begun before surgery and continued during the first 48 h after operation significantly attenuates the decrease in the postabsorptive muscle protein synthesis rate associated with surgical injury. Effective block of nociceptive stimuli thus preserves tissue protein synthesis.

Adenocarcinoma↗
PubMed1996

Aortic wall structural strengthening by intraluminal net prosthesis to arrest aneurysm progression and to prevent dissection and rupture.

The major limitation implicit in the endovascular procedures for aortic prosthetic substitution is that they cannot be used in those tracts of the aorta where important collateral branches originate (aortic arch, thoraco-abdominal tract, upper abdominal), that would be occluded by the prosthesis. In order to overcome this limitation we hypothesized the endovascular positioning of a prosthesis in the form of a wide mesh network that would be gradually and spontaneously covered by new intima and included in the aortic wall. The fabric framework linked to the aortic wall would then condition its significant, regular and uniform mechanical strengthening that fractionates and partially absorbs the centrifuge pulsatile stress of the bloodstream. The purpose of this paper is to report the results of the insertion of a braided Prolene net prosthesis in the first 7 cm of the descending aorta of ten swine. The animals were killed after 6 weeks, the substituted segment removed and aortic wall compliance measured under standardized conditions. The prosthesis was found entirely covered by new intima, well embodied in the aortic wall. The intercostal collateral included in the substituted segment was patent, as proved by bubble formation during underwater insufflation. Compliance of the prosthesis segment was significantly lower than that of the adjacent descending aorta. Histology showed a regular net prosthesis inclusion deep in the neo-intima layer. Present results indicate the technical feasibility of the procedure, achieving significant aortic wall strengthening without affecting the collateral (intercostal) circulation.

Aortic Dissection↗
PubMed1996

A new tracheal tube for difficult intubation.

We have compared a new Portex tracheal tube with the Oxford tube in performing simulated grade 3 difficult intubations. The Portex tube was modified so that the bevel faced backwards, as in the Oxford tube. A gum elastic introducer was used with both tubes. The time taken and number of attempts needed were recorded, with changes in arterial pressure, heart rate and incidence of sore throat. Both tubes were successful in avoiding the problem of obstruction at the cords, which occurs when a standard Magill tube is used with an introducer. Thus the new tube has the merits of the Oxford tube without the disadvantages of rubber. It is suitable for both easy and difficult intubations with advantages in safety, cost and convenience. An unexpected but important finding was a clear learning effect, despite both investigators being familiar with the technique at the outset. Over the course of the study, intubation time decreased progressively (P < 0.001). This provides new evidence of the need for trainees to practise the art of intubation when the cords are not visible. Our estimate of the learning "half-life" was 15 intubations; we conclude that 30 simulated grade 3 intubations would be a reasonable objective for trainees before handling high-risk cases.

Adult↗
PubMed1996

Cardiac arrest after Caesarean section under subarachnoid block.

Cardiac arrest occurred on arrival in the recovery room after emergency Caesarean section under subarachnoid block. The patient was resuscitated successfully and recovered with no adverse effects. The current literature is reviewed and the pathophysiological mechanisms involved in the aetiology of cardiac arrest under subarachnoid block are discussed. Early use of adrenaline to treat severe bradycardia or hypotension is recommended.

Adult↗
PubMed1996

[Characteristics of a new controlled release formulation of ursodesoxycholic acid].

Ursodeoxycholic acid, like all weak acids, has to be formulated so as his release and absorption depend as little as possible by the pH of gastrointestinal tract. To obtain this result a controlled release formulation of UDCA was developed, based on bioadhesive technique. This allowed a longer residence and absorption time of the active ingredient both at gastric (due to gastrosoluble rate) and duodenal-jejunum level (gastroresistant rate). Thus, all the absorption windows for bile acids are utilized, to ameliorate the total bioavailability of the drug.

Biological Availability↗
PubMed1995

Body heat transfer during hip surgery using active core warming.

The purpose of this study was to evaluate the effect of core warming on heat redistribution from the core to the periphery as manifested by changes in core, mean skin temperature and mean body heat, investigated in a group of 30 patients undergoing total hip replacement. The control group (n = 10) had no active warming. Core warming was achieved in the humidifier group (n = 10) by using humidified and warmed gases at 40 degrees C, whilst in the oesophageal group (n = 10), an oesophageal heat exchanger was used to achieve active warming. Operating room temperature and relative humidity was standardised. Aural canal and skin temperatures (15 sites) were measured before induction of anaesthesia, at the end of surgery and one hour of recovery after anaesthesia. Mean skin temperatures were calculated for a weighted four and unweighted 15 points, and mean body heat were calculated to quantify the distribution of body heat. Core temperature decreased in the control and the oesophageal groups, but not in the humidifier group at the end of surgery; by mean values +/- SD of 1.9 degrees C +/- 0.6, 1.2 degrees C +/- 0.6 and 0.4 degree C +/- 0.2 degree C, respectively (P < 0.01). Mean skin temperature (MST15) decreased in the control group by 1.0 degree C +/- 1.0, but not in the actively warmed groups where the mean increased by 0.1 degree C +/- 1.4 and 0.2 degree C +/- 0.2 in the oesophageal and humidifier groups, respectively (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Increase in Mallampati score during pregnancy.

A photographic version of the Mallampati test was developed and applied to 242 pregnant patients at 12 weeks' gestation and again at 38 weeks' gestation. At 38 weeks the number of grade 4 cases had increased by 34% (P < 0.001). This is in agreement with other evidence which suggests that difficult laryngoscopy is slightly more frequent in obstetrics (1.7%) than in general surgery (1.3%). The increase in Mallampati score correlated with gain in body weight (r = 0.3, P < 0.001), which gives some support to the concept that fluid retention is the underlying cause. We conclude that pharyngeal oedema causes some hindrance to tracheal intubation in obstetrics, but not enough to explain the high failure rate reported. A case is made for rationalizing the management of difficult intubation. Our data also show that more research is needed on factors which affect Mallampati's test, particularly neck extension.

Anthropometry↗
PubMed1995

Post-surgery epidural blockade with local anaesthetics attenuates the catecholamine and thermogenic response to perioperative hypothermia.

Core (aural canal) and mean skin (15 sites) temperatures, plasma adrenaline, noradrenaline and metabolites, and gaseous exchange were measured before, during and for 4 h after surgery in sixteen patients scheduled for elective colorectal surgery. All patients received general anaesthesia and no measures were taken to prevent the perioperative loss of body heat. At time of abdominal wall closure, when the core temperature was below 35.0 degrees C, the patients were randomly allocated to receive either 20-30 mg of papaveretum i.v. (papaveretum group, n = 8) or 15 ml of bupivacaine 0.75% via thoracic (T9) epidural route to obtain a T4-S5 sensory blockade (epidural group, n = 8). Continuous infusion of either i.v. papaveretum or epidural 0.25% bupivacaine was continued after surgery. During the recovery period of four hours the rate of increase in core and mean skin temperatures was significantly slower in the epidural group compared with the papaveretum group (P < 0.01). Plasma catecholamine concentrations remained elevated after surgery in the papaveretum group, whilst they decreased significantly once epidural blockade was established (P < 0.001). There was a lower trend, however not significant, in the rise of postoperative oxygen consumption and plasma glucose concentration in the epidural group compared with the papaveretum group.

Aged↗
PubMed1994

Metabolic and inflammatory responses after open or laparoscopic cholecystectomy.

Metabolic and inflammatory responses and changes in fatigue were studied in groups of patients undergoing either laparoscopic (n = 14) or open (n = 10) elective cholecystectomy. The mean(s.e.m.) cortisol concentration was significantly (P < 0.001) increased from 342(80) and 424(91) nmol l-1 before operation to 895(46) and 966(53) nmol l-1 after surgery in patients undergoing laparoscopic and open cholecystectomy respectively. There was no difference in cortisol response between the groups. Glucose concentration was increased (P < 0.02) at the end of surgery from mean(s.e.m.) preoperative levels of 5.54(0.15) and 6.16(0.15) mmol l-1 to postoperative values of 7.46(0.29) and 8.46(0.86) mmol l-1 for the laparoscopic and open procedures respectively. The mean glucose concentration during the initial 12 h after surgery was significantly greater (P < 0.02) following open than laparoscopic cholecystectomy. The mean(s.e.m.) albumin concentration fell significantly (P < 0.01) during surgery by an equivalent extent from 38.9(0.77) and 38.5(1.10)g l-1 to 35.2(0.79) and 34.6(0.97) g l-1. The mean (95 per cent confidence interval) interleukin (IL)6 concentration peaked 4 h after surgery at 57.2 (44.6-73.4) pg ml-1 following laparoscopic and 99.3 (72.8-135.4) pg ml-1 after open cholecystectomy. Mean (95 per cent confidence interval) C-reactive protein (CRP) levels at 24 h were 17.0 (12.7-21.2) and 49.0 (25.3-93.6) mg l-1 and at 48 h 28.0 (21.4-35.4) and 70.0 (36.4-133.6) mg l-1 following laparoscopic and open operations. The differences in IL-6 and CRP level between the groups were significant (P < 0.01). Mean(s.e.m.) fatigue scores were significantly (P < 0.05) increased from preoperative values of 2.4(0.24) and 2.6(0.44) to 5.5(0.56) and 6.8(0.51) at 24 h after laparoscopic and open operations. At 48 h the mean(s.e.m.) fatigue score (5.6(0.57)) remained significantly (P < 0.05) raised only after open cholecystectomy. Hand grip strength was significantly (P < 0.05) reduced only after the open procedure, to a mean(s.e.m.) of 88(6) per cent of the preoperative value. These results demonstrate that aspects of the metabolic and acute-phase responses are attenuated following laparoscopic cholecystectomy, consistent with a reduction in tissue trauma.

Blood Glucose↗
PubMed1994

Prevention of hypothermia during hip surgery: effect of passive compared with active skin surface warming.

We have measured aural canal (core) and skin temperatures, and body heat content in 45 patients undergoing elective hip arthroplasty. They received general anaesthesia which included thiopentone, vecuronium and enflurane and nitrous oxide in oxygen. Patients were allocated randomly to three groups: group 1, control (n = 15), received no intraoperative warming device; group 2 had passive skin surface warming (metallized plastic sheet, Thermolite (n = 15); and group 3 had active skin surface warming (forced heated air, Bair-Hugger) (n = 15). Duration of surgery, fluid administration and the temperature and relative humidity of the operating theatre were similar for the three groups. Core temperature and mean body heat content decreased significantly during surgery in groups 1 and 2 (aural canal temperature 1.5 and 1.0 degrees C, and mean body heat content 287 and 189 kJ, respectively), while in group 3 these variables remained near preoperative values (P = 0.001). Mean skin and hand temperatures decreased in the control group, increased in the active warming group and were unchanged in the passive warming group (P < 0.005), indicating that the forced heated air system was very efficient in providing thermal homeostasis during surgery, while the metallized plastic sheet was able to insulate the skin only from radiant and convective heat losses, without attenuating the reduction in core temperature.

Aged↗