[Short-term results in colorectal surgery. Statistical analysis about mortality, morbidity and hospital stay]. / Risultati a breve temine della chirurgia colo-rettale. Studio statistico su mortalità, morbilità e tempi di degenza.

AIM: The surgical approach on the colon and rectum represents a wide slice of the surgical procedures carry out in election or emergency in a general surgery unit. The literature reports prospective and retrospective studies evidencing emergency surgery, advanced age, comorbidity and other factors can determinate a worsening of short-term outcome (postoperative mortality, morbidity and hospital stay). The aim of the study was to verify, through a statistical analysis on a group of patients operated on the colon and the rectum, which are the factors weighting on the short-term outcome. METHODS: Our retrospective study is carried out on 150 patients consecutively operated on the colon and rectum from January 2002 to September 2004 in elective or emergency surgery in the Unity of General Surgery of the Hospital S. Maria Nuova Azienda Sanitaria of Florence. The variables for the statistical analysis were: sex, age, comorbidity, nature of pathology, timing of surgery, type of emergency, lesion location, surgical intervention, presence of social factors delaying the discharge, blood transfusion, Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM-score). RESULTS: The mortality study found the advanced age (>70 years) as risk factor in the univariate analysis, not confirmed in the multivariate one. The morbidity study found advanced age, presence of comorbidity and blood transfusion as risk factors in the univariate analysis, not confirmed in the multivariate one. The POSSUM-score represents in both multivariate analyses the only statistically meaningful parameter correlated with mortality (P<0.005) and morbidity (P<0.05). The multivariate analysis in the study on the hospital stay found that more staged surgery carry to a lengthening of hospital stay (P<0.0001); in minor such measure blood transfusion (P=0.0005), emergency surgery (P=0.002) and presence of social factors (P=0.008); comorbidity (P=0.02) and advanced age (P=0.03) had less statistical weight. CONCLUSIONS: Despite of the literature, this study found none of the analyzed variables related on postoperative mortality and morbidity in statistically meaningful way. The POSSUM-score demonstrated once again validity in estimating the probability of dead and of postoperative complications. The variables that influenced in lengthening of hospital stay were: more staged surgery, blood transfusion, emergency surgery, presence of social factors conditioning the discharge, comorbidity and advanced age of the patients. The good results about mortality and morbidity can be explained by the fact we prefer in emergency more staged surgery that protect the patients from complications related to the anastomosis, the presence of sub-intensive surgical beds with a constant monitoring of high risk patients and the close collaboration between surgeons and intensive care medical doctors.

Skin temperature during sympathetic block: a clinical comparison of bupivacaine 0.5% and ropivacaine 0.5% or 0.75%.

Measurement of skin temperature can be used as an indicator of sympathetic blockade induced by neuraxial anaesthesia. The aim of the study was to test the skin temperature response to epidural administration of bupivacaine and different concentrations of ropivacaine. Forty-eight ASA class I-II patients undergoing herniorraphy were enrolled into a prospective, randomized, double-blind clinical trial. Patients were randomly allocated to receive epidural anaesthesia with a single dose of 18 ml of bupivacaine 0.5% (n=16); ropivacaine 0.5% (n=16), or ropivacaine 0.75% (n=16). A temperature probe was positioned on the skin of the thigh and skin temperature registered before epidural anaesthesia, every 10 minutes for the first hour after the epidural injection and every hour for the following four hours. Sensory blockade was assessed by pinprick and motor blockade using the Bromage scale. No significant difference was observed in sensory or motor blockade. A skin temperature rise of 1 to 1.8 degrees C compared with basal values was observed in all patients within the first hour. Temperature returned to basal values within four hours in the ropivacaine 0.5% group, within five hours in the ropivacaine 0.75% group, and remained 1 degrees C higher after five hours in the bupivacaine 0.5% group (P<0.01). The duration of sympathetic block is significantly shorter with ropivacaine than with bupivacaine.

In vitro evaluation of a system for pH-controlled peroral delivery of metformin.

Oral absorption of the antihyperglycaemic agent metformin (MF x HCl) is confined to the upper part of the intestine, therefore controlled-release oral formulations of this drug should ensure a complete release during transit from stomach to jejunum. Compressed matrix tablets based on pH-sensitive poly(ethylene oxide) (PEO)-Eudragit L100 (EUD L) compounds have shown in vitro a compliance with the above requirement. The polymer compounds were prepared by a coevaporation process. The release pattern of MF x HCl from matrices depended on the PEO-EUD L ratio in the coevaporate. The 1:1 (w/w) ratio was unable to control MF x HCl release in simulated gastric fluid (SGF, pH 1.2), because the matrix material was excessively hydrophilic. Nevertheless, the release rate in SGF could be modulated by increasing the EUD L fraction in the coevaporate. With a PEO (M(w), 400 kDa)-EUD L (1:2, w/w) ratio the percent dose released in 2 h to SGF, where the coevaporate was insoluble, was around 23 or 50% with 10 or 20% loading dose. The release was then completed within the successive 2 h of elution with simulated jejunal fluid (SJF, pH 6.8) where EUD L and the coevaporate gradually dissolved. Release in SGF was controlled by matrix swelling and/or drug diffusion in matrix, whereas matrix dissolution controlled release in SJF. The unique release-controlling properties of the polymer compounds were due to PEO-EUD L macromolecular interactions. Matrices show promise of a gradual and complete release of MF x HCl from stomach to jejunum, unaffected by gastric pH fluctuations. This mode of administration might allow the use of lower therapeutic doses compared to existing immediate- or sustained-release products, thus minimising side effects.

[Sevoflurane in stop-flow interventions. Hemodynamics study]. / Sevoflurano per interventi di "stop-flow". Uno studio emodinamico.

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.

[Reconstruction of the aortic root: midterm results]. / Ricostruzione della radice aortica: risultati a medio termine.

BACKGROUND: The aim of this study was to assess mid-term results of aortic reconstruction. METHODS: According to Dr. David's technique, 20 patients (17 males, 3 females, median age 63 years) were examined, who underwent surgery between September 1996 and August 1999. Indications for operation were aortic insufficiency with ascending aorta aneurysm in 19 patients, and acute Stanford type A dissection in 1 patient. In every patient the native valve was preserved and suspended inside a tubular prosthesis on which the coronaries were reimplanted. RESULTS: No patient died in hospital. Follow-up (mean 13 months) was complete for all patients. One patient died of extracardiac causes. Seventeen of 19 survivors are in NYHA functional class I, the remaining 2 in class II. Nineteen patients underwent echocardiography which showed moderate aortic regurgitation in 1, mild in 6 and absent or trivial in 12. There were no instances of thromboembolism. CONCLUSIONS: These results are encouraging and have brought us to consider aortic reconstruction a valid alternative to traditional aortic root replacement. Dr. David's technique is reproducible and reliable in the long term.

Informed consent and patient participation in the medical encounter: a list of questions for an informed choice about the type of anaesthesia.

The present study was undertaken to evaluate the impact of a new procedure for eliciting informed consent by patients undergoing minor surgical procedures, in which the choice between general anaesthesia (GA) and regional anaesthesia (RA) was possible. In this prospective study, two randomly selected groups of patients were compared: study group (SG), 52 patients, received from the nurse before the preoperative interview, a list of seven questions, which they were invited to ask the anaesthetist; while the control group (CG), 73 patients, did not receive any suggested questions. There were two end points: the proportion that chose RA and the number of questions actually addressed to the doctor at the preanaesthetic interview. Psychological aspects were taken into account by collecting the Hospital Anxiety and Depression (HAD) scale before the preanaesthetic interview. Satisfaction with the interview was recorded using a telephone questionnaire 2 weeks after the operation. The results from the two groups were compared by calculating the odds ratio according to Mantel-Haenszel and by logistic analysis. Altogether, 71.2% of the patients chose RA without any difference between the groups. The average number of questions asked by each SG patient was higher than for the CG (1.67 vs. 0.96). The satisfaction level was similar in the two groups. Our list of questions was designed to facilitate patient autonomy. It offered an aid to those requesting more information and assisted communication. The method did not change the proportion who chose a specific kind of anaesthesia, but does seem to improve patient participation in the decision-making process.

Linear segmental annuloplasty for mitral valve repair.

A method of posterior mitral annulus remodeling is presented. The posterior annulus is divided into three segments, each segment encircled by a suture that is passed in a tourniquet. Coaptation of the leaflets can be achieved by tightening the tourniquets while the ventricle is being filled. This technique is simple and quick, avoids the use of foreign material, and requires less expertise and judgment than traditional annuloplasties.

[Anesthesia with sevoflurane vs propofol in elective extracavity surgery]. / Anestesia con sevoflurano vs propofol nella chirurgia d'elezione extracavitaria.

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.

Echocardiographic assessment of aortic valve replacement with stentless porcine xenografts.

Stentless porcine xenografts (SPXs) implanted in the aortic position have potential hemodynamic advantages over traditional valve prostheses because of the lack of a rigid stent. Twenty-four patients (mean age 59 years) who underwent aortic valve replacement with SPXs were studied by echocardiography early after and 26 +/- 10 months (range 8 to 40) after operation. Peak and mean gradients, as well as aortic valve area, did not change significantly from baseline (16.3 +/- 8 and 9.8 +/- 5.6 mm Hg, and 1.78 +/- 0.63 cm2, respectively) to follow-up study (12.5 +/- 5 and 7.7 +/- 3 mm Hg, and 1.8 +/- 0.65 cm2, respectively). At baseline, color flow Doppler imaging showed aortic valve regurgitation where the leaflets coapted centrally in 17 of 24 patients (trivial, n = 14; mild, n = 3). Besides the central leak, paravalvular regurgitation was seen in 4 patients (trivial, n = 3; mild, n = 1). At follow-up, 18 of 24 patients had aortic valve regurgitation (trivial, n = 11; mild, n = 6; and moderate, n = 1). New valvular regurgitation (graded as trivial, n = 2; mild, n = 2; and moderate, n = 1) was detected in 5 patients, and new paravalvular regurgitation (graded as mild) developed in 1 patient. Two patients underwent repeat operation for valve-related complications: (1) rupture of a valve cusp with acute pulmonary edema, and (2) fibrotic stenosis of the left coronary ostium with unstable angina. In conclusion, this study demonstrates good hemodynamic performance of the SPX in the aortic position.(ABSTRACT TRUNCATED AT 250 WORDS)

[Gelatin for volume replacement in hemodilution: hemodynamic study]. / Le gelatine come soluzione di rimpiazzo in corso di emodiluizione: uno studio emodinamico.

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.

[Dextran-induced anaphylactoid reaction (DIAR). 2 clinical cases]. / Reazione anafilattoide al destrano (DIAR). Due casi clinici.

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.

The role of transesophageal echocardiography in the monitoring of cardiac mass removal: a review of 17 cases.

Intraoperative transesophageal echocardiography (TEE) was used to monitor the removal of intracardiac masses in 17 patients. Prebypass TEE was used to confirm the preoperative diagnosis. It gave a clear image and anatomical definition of the mass in 16 cases. Moreover, in 11 of these patients, prebypass TEE provided information not obtained previously by traditional exams. This information was judged either useful or indispensable for a successful outcome in 10 of these patients. However, in one of the remaining six patients, TEE did not clearly visualize a flat thrombus in the left atrium. Postbypass TEE was used in each case to monitor the surgical results of the mass removal and the associated procedures. In one patient, it disclosed a progressively expanding hematoma in the left atrial wall, which was interfering with mitral valve function. From this experience, we consider intraoperative TEE the best monitoring device during cardiac mass removal because it usually provides a more complete diagnosis and anatomical definition of the mass than the traditional preoperative methods and permits monitoring of the surgical results before chest closure. Some limitations to this method may exist.

[Comparison of crystalloids and hydroxyethyl starch during normovolemic hemodilution. A study of hemodynamics and saturation measurement]. / Confronto tra cristalloidi ed amido idrossietilico in corso di emodiluizione normovolemica. Uno studio emodinamico e saturimetrico.

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.

[Intraoperative changes in aerobic and anaerobic metabolism as prognostic index in interventions of massive hepatic resection]. / Variazioni intraoperatorie del metabolismo aerobio ed anaerobio come indice prognostico negli interventi di resezione epatica massiva.

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)