"When something goes wrong".

Background: Aspiration of food or liquids can result in suffocation, evolving in coughing, difficulty breathing and forced exhalation. Asphyxia occurs when the aspirated material occludes the upper airways, either in the proximal or distal tract, resulting in the inability to breathe. The risk of asphyxiation death, is increased if a person makes sudden movements while eating, walks or runs while eating, or even becomes distracted or frightened. It is higher in individuals with neurological diseases, intellectual disability (ID), cognitive impairment, psychiatric pathologies or their pharmacological treatments and people carrying additional physiological impairments, which can cause oral dysfunction and dysphagia. Protective mechanisms may sometimes lack or fail to expel food fragments stuck in the airways, which completely obstruct them. Case series: The authors present some peculiar cases of subjects who died from food bolus choking, namely a case of mozzarella-cheese clogging in a young subject (25 years old) undergoing rehabilitation treatment following a stroke; a 38-year-old man with middle-grade mental retardation died from first airway food bolus (mush of bread) clogging; a 26-year-old subject with epilepsy died from tripe clogging in the course of a seizure; a 38-year-old subject in psychiatric treatment for depressive disorder who died from clogging with octopus tentacles. Conclusion: Food bolus clogging asphyctic deaths generally occur in subjects with psychic/neurological pathologies, resulting in altered deglutition mechanisms or lack of protective reflexes. Foodstuff, especially if large or viscous, obstruct the proximal or distal airways, leading to acute respiratory failure and death. Autopsy is diriment in ascertain the cause of death.

Regional anesthesia for carotid endarterectomy: a comparison between ropivacaine and levobupivacaine.

BACKGROUND: This study compares ropivacaine and levobupivacaine when administered for cervical plexus block. The authors therefore compared the arterial pressure profile and the incidence of hypotension between drugs. METHODS: Forty-eight patients scheduled for carotid artery surgery (American Society of Anesthesiologists [ASA] 2-3) were randomly assigned to receive levobupivacaine or ropivacaine (24 patients each). Neurological status, arterial pressure profile and control of postoperative pain were the main observed parameters. All patients had severe carotid stenosis (>80%) and/or had suffered transient ischemic attacks (TIAs) or preoperative strokes. The same team performed anesthesia and surgery for carotid endarterectomy; the cervical block was performed according to Moore's technique.Arterial pressure, heart rate and S(a)O(2p) were monitored continuously with particular regard to T0 (baseline), T1 (immediately before carotid clamping), T2 (immediately before declamping) and T3 (at the end of the procedure). Hypotension was defined as the fall of arterial systolic pressure 30% below baseline or less than 100 mmHg. RESULTS: Arterial pressure fell significantly in both groups at T1 with respect to T0 (P<0.0001). Levobupivacaine patients showed higher mean arterial pressure on T0 (112+/-12 mmHg versus 103+/-7 mmHg; P<0.05), thus suggesting a more pronounced vasodilator effect, as confirmed by the larger drop of arterial diastolic pressure (P=0.007). An absolute 6% difference of hypotension-related drug was recorded with levobupivacaine (19%) as compared with ropivacaine (13%) (P=0.28). CONCLUSIONS: Levobupivacaine has a greater vasodilatory effect than ropivacaine. Its higher incidence of hypotension, although not statistically significant, suggests ropivacaine as the drug of choice for cervical plexus block.

Application of pressure mapping techniques to measure push and gripping forces with precision.

Gripping and push forces, also named coupling forces, have induced effects on the transmission of the vibration in the upper limb. The assessment of the vibration exposure with powered tools thus requires that these man/machine coupling parameters are controlled and monitored. To date, no reliable metrological systems enable their precise measurements. This study first investigated how much precision could be expected from the pressure mapping technique for the determination of coupling forces by means of numerical integration. Then a specific procedure was worked out and validated to instrument hand-held tools and measure the coupling forces with regard to the appropriate current standards. The proposed method was applied as a case study on an ordinary breaker and an anti-vibration breaker.

Planning and executing a vaccination campaign against avian influenza.

Vaccination against avian influenza infection caused by H5 or H7 virus subtypes has been used on several occasions in recent years to control and in some cases eradicate the disease. In order to contain avian influenza infection effectively, immunization should be combined with a coordinated set of control and monitoring measures. The outcome of an immunization campaign depends on the territorial strategy; whereas the capacity of the veterinary services in developed countries permits enforcement of strategies aimed at eradicating avian influenza, many countries currently affected by highly pathogenic avian influenza (HPAI) H5N1 viruses have a limited veterinary infrastructure and a limited capacity to respond to such epidemics. In these countries, resources are still insufficient to conduct adequate surveillance for identification and reaction to avian influenza outbreaks when they occur. When properly applied in this scenario, immunization can reduce mortality and production losses. In the long term, immunization might also decrease the prevalence of infection to levels at which stamping-out and surveillance can be applied. Countries should adapt their immunization programmes to local conditions in order to guarantee their efficacy and sustainability. In the initial emergency phase, human resources can be mobilized, with reliance on personal responsibility and motivation, thus compensating for potential shortcomings in organization. A more appropriate allocation of resources must be pursued in the long term, remembering that biosecurity is the main component of an exit strategy and must always be improved.

Abdominal aortic aneurysm resection following cholecystectomy and heart transplantation. Case report.

The case of a patient who underwent heart transplantation and cholecystectomy in 1993 and admitted for resection of abdominal aortic aneurysm in May 1997, is reported. About 25 minutes after unclamping the abdominal aorta the patient s blood pressure fell suddenly to 70/40 mmHg. In spite of vigorous fluid administration and infusion of Dopamine and Adrenaline the hemodynamic pattern returned to normal only 15 minutes later. The authors discuss the possible explanations of this behaviour (mesenteric traction syndrome, hypovolemia) and conclude that heart transplant patients are particularly affected by hypotension. Of paramount importance remains therefore the correct evaluation of adequate filling pressures which should be maintained slightly above normal range.

Analytical performance characteristics of thin and thick film amperometric microcells.

The analytical performance of amperometric microcells with different electrode geometries is compared for enzyme activity measurements. The microcells were fabricated with thin film photolithography or thick film screen-printing in four different designs. The cells made with the thin film process used flexible substrate with microelectrode array or a circular, disk-shaped working electrode. The screen-printed working electrodes had semicircle or disk shape on ceramic chips. Putrescine oxidase (PUO) activity measurement was used as a model. The determination of PUO activity is important in the clinical diagnosis of premature rupture of the amniotic membrane. An electropolymerized m-phenylenediamine size-exclusion layer was used to eliminate common interferences. The size exclusion layer revealed also to be advantageous in protecting the electrodes from fouling by putrescine (enzyme substrate). The electrode fouling of bare electrodes was insignificant for screen-printed electrodes, but very severe for electroplated platinum working electrodes. The microelectrode array electrodes demonstrated smaller RSD and higher normalized sensitivities for hydrogen peroxide and PUO activity. All the other electrodes were demonstrating comparable analytical performances.

Pressure-flow studies in men with benign prostatic hypertrophy before and after treatment with transurethral needle ablation.

BACKGROUND/AIMS: In this study we wanted to examine the effects that transurethral needle ablation (TUNA) might have on the urodynamic characteristics of bladder outlet obstruction and to evaluate the clinical changes and the safety profile in patients undergoing the TUNA procedure, including the effects on erectile and ejaculatory function. MATERIALS AND METHODS: We evaluated 24 patients, aged between 66 and 81 (mean 73.4) years with a mean prostatic volume of 57 +/- 15 ml. Before treatment, the clinical history was collected, then prostate-specific antigen (PSA) analysis, digital rectal examinations, I-PSS and quality-of-life (QOL) tests, uroflowmetry with residual volume, and pressure-flow studies were performed in all patients. After treatment, all the patients were evaluated at 6, 12 and 24 months by the same parameters. RESULTS: After treatment, the I-PSS and QOL scores were considerably improved, and the mean flow rate and the residual volume were also improved. The serum PSA level remained unchanged. The prostatic volume was almost unchanged, and pressure-flow studies showed a reduction in the mean opening pressure and detrusor pressure at maximum flow after treatment. None of the patients complained of alterations in sexual activity nor retrograde ejaculation. CONCLUSIONS: Our study confirms that in patients with benign prostatic hyperplasia, the TUNA procedure results in no major complications and in significant clinical improvements. There was an improvement in the subjective and objective variables, such as symptom scores and frequency-volume charts and, in the majority of patients, subjective and objective improvements were sustained for the duration of this study, which included a 2-year follow-up with pressure-flow studies. From our experience we can say that the ideal candidate for TUNA treatment should be younger than 70 years, with a prostatic volume of <60 cm H(2)O, with a baseline detrusor pressure at maximum flow of <60 cm H(2)O, with a pretreatment residual volume of <100 ml and with a QOL score of <5.

[Interstitial laser coagulation of the prostate in patients with prostatic hypertrophy: preliminary results with medium-term follow-up]. / Coagulazione laser interstiziale (ILC) della prostata in pazienti affetti da ipertrofia prostatica: risultati preliminari con follow-up a medio termine.

Although transurethral resection of the prostate (TURP) is the gold standard for treatment of BPH, a new, minimally invasive technique, called Interstitial Laser Coagulation (ILC), introduced by Muschter and Hofstetter, has been developed to treat BPH. ILC is base on the coagulation of prostatic tissue by means of diffused laser light using a diode laser system with a temperature feed-back (Indigo Medical 830e TM). We report our results in treating 20 patients with BPH and Bladder Outlet Obstruction (BOO), after a mean follow-up of 7 months. To define the indication for treatment and to monitor the success, urinary flow-rate (Omax), I-PSS symptoms score, residual urinary volume and prostate volume determined by ultrasound were recorded before treatment and after 3, 6, 12 months. Transurethrally, under spinal or regional anaesthesia, 2 or 3 insertions of the laser fibre in each prostatic lobe were performed beginning at the apex directly proximal to the bladder neck, made at 1 cm intervals, using a modified model Olympus cystoscope. After 6 months, Qmax increased from 6, 7 ml/sec to 11, 3 ml/sec; I-PSS score decreased from 18 to 8; residual urinary volume from 130 ml to 40 ml, prostate volume decreased from 60 to 48 ml. In selected cases, urodynamic evaluation was performed before and after treatment. Urodynamic findings were classified according Shafer diagram to grade B.O.O.: the score was 4 before treatment and 2 after 6 months. We observed UTI in 3 cases, retrograde ejaculation and acute urinary retention in 1 case, transitory irritative and obstructive syndrome in 8 cases after treatment. ILC is a simple, safe and effective treatment for BPH with significant improvements in both objective and subjective parameters. It is cheaper than others mini-invasive therapies and is able to treat any prostate volume, saving urethra and sexual function.

Change in major amputation rate in a center dedicated to diabetic foot care during the 1980s: prognostic determinants for major amputation.

From 1990 to 1993, 115 diabetic patients were consecutively hospitalized in our diabetologic unit for foot ulcer and 27 (23.5%) major amputations were carried out. The major amputation rate of this series of cases was compared with that occurring in diabetic subjects taken into our hospital for foot ulcer in two previous periods: 1979-1981 (17 major amputations in 42 inpatients or 40.5%) and 1986-1989 (26 major amputations in 78 inpatients or 33.3%). The comparison shows a progressive reduction in major amputation rate [Odds ratio 0.66, 95% confidence interval (CI) 0.46-0.96]. Univariate and multivariate analysis, carried out in the population of the 1990-1993 period, in order to detect the independent factors associated with major amputation show the following prognostic determinants of major amputation: Wagner grade (odds ratio 7.69, CI 1.58-37.53), prior stroke (odds ratio 35.05, CI 3.14-390.53), prior major amputation (odds ratio 3.49, CI 1.26-9.38), transcutaneous oxygen level (odds ratio 1.06, CI 1.01-1.12), and ankle-brachial blood pressure index (odds ratio 4.35, CI 1.58-12.05), while an independent protective role was attributed to hyperbaric oxygen treatment (odds ratio 0.15, CI 0.03-0.64). In accordance with other studies, we, therefore, conclude that a comprehensive protocol as well as a multidisciplinary approach in a dedicated center can assure a decrease in major amputation rate. The parameters of limb perfusion were the modifiable prognostic determinants most strongly predictive for amputation.

[Evaluation of renal function during orthotopic liver transplantation]. / Valutazione della funzione renale in corso di trapianto ortotopico di fegato.

BACKGROUND: Orthotopic liver transplantation (OLI) is a recognised means of therapy for endstage liver failure (ESLF). Both the preoperative alterations of renal function, closely correlated with the ESLF, and the frequent and abrupt changes of circulating blood volumes occurring during the various phases of OLT are able to significantly alter renal function during the perioperative period. METHODS: In order to define the specific changes of renal function during the various phases of OLT, six postnecrotic cirrhotic patients undergoing their first OLT entered a prospective study protocol. All the patients had standard and anesthetic techniques including the venovenous bypass (VVBP) during the anhepatic phase. At standard intervals (baseline, during hepatic dissection, during the anhepatic phase, following reperfusion, at the end of surgery) together with complete hemodynamic and metabolic profiles, arterial blood and urine samples were obtained to determine electrolytes and creatinine concentrations, blood levels of atrial natriuretic factor, aldosterone and renin activity. Using standard formulas creatinine clearance (Ccreat) and Na absolute and fractional excretions (FeNa%) were calculated. RESULTS: Major changes in the hemodynamic profile occurred during the anhepatic phase in spite of the use of the VVBP (reduced cardiac index, reduced pulmonary wedge pressure, increased systemic vascular resistances). Concomitantly a significant decrease in Ccreat (-67%) and in urinary output, was present while aldosterone and renin activity increased. The changes in Ccreat persisted at the end of surgery in spite of the optimal hemodynamic profile. Aldosterone and renin activity returned to values close to baseline at the end of surgery. CONCLUSIONS: From these data it is possible to conclude that renal function markedly deteriorates during OLT and it has to be considered at increased risk in the immediate postoperative period. The use of VVBP does not seem to prevent the intraoperative renal impairment.

[Gene p53 mutation and prognosis in bladder tumors]. / Mutazione del gene p53 e prognosi nei tumori vescicali.

The choice of treatment for bladder tumors is based on pathological criteria, i.e. staging and grading mainly. It has recently been observed that genetic alterations that involve activation of oncogenes and inactivation of suppressor genes can occur during tumorigenesis. p53 protein is coded for by a genes on chromosome 17, and is able to suppress malignant transformation and proliferation; it can be important in maintaining the integrity of DNA, when damaged during neoplastic disease. We have analyzed samples of transitional cell carcinoma of the bladder of 60 patients managed by conservative treatment; all the specimens have been stained for p53 protein. We could observe that the presence of the protein p53 is correlated with staging and grading and is associated with an increased risk of relapse and progression. Patients with transitional-cell carcinoma confined to the bladder that demonstrates nuclear p53 reactivity should be considered for protocols of adjuvant treatment.

[Laparoscopic cholecystectomy in patients previously treated with heart transplantation. A clinical case]. / Colecistectomia per via laparoscopica in paziente precedentemente sottoposto a trapianto cardiaco. Caso clinico.

A 46-years old patient who had already undergone cardiac transplantation was scheduled for laparoscopic cholecystectomy following a diagnosis of cholelithiasis. In this particular case we were not faced with any problems even in presence of a denervated heart. Since the patient was immnosuppressed, we had to look for the best compromise between the need of monitoring closely the most important vital parameters and contemporarily reducing invasivity as much as possible. Capnometry was of paramount importance, enabling us to prevent and to correct high paCO2 values. The rapid recovery of the patient allowed us to begin with food intake and oral immunosuppressive therapy already 24 hours after the operation and to discharge the patient on the third day after surgery. Laparoscopic cholecystectomy represented a successful choice and a satisfying procedure both for the anaesthesiologist and for the patient, particularly regarding the minimal invasivity and the rapid recovery, which were considered of great importance in the immunodepressed patient.

Pharmacokinetic profile of the induction dose of propofol in chronic renal failure patients undergoing renal transplantation.

STUDY OBJECTIVE: To define the pharmacokinetic profile of the induction dose of propofol in chronic renal failure patients. DESIGN AND SETTING: Determination of propofol blood concentrations after the bolus dose of 2 mg.kg-1 bw injected in 30 seconds in a peripheral vein in a group of chronic renal failure (CRF) patients and in a group of normal patients (controls). PATIENTS: 10 CRF patients (7 males, 3 females, mean age 47 +/- 8 years old, mean body weight 66 +/- 8 kg) candidates to cadaveric renal transplantation and free from major hepatic diseases (study group); 8 ASA I patients (5 males, 3 females), without major cardiorespiratory, hepatic, renal, hematologic or metabolic diseases undergoing minor elective surgical procedures lasting from 50 to 90 minutes (control group). MEASUREMENTS: a) propofol blood concentrations by means of HPLC; b) derived pharmacokinetic parameters (calculated by means of Siphar, version 4.0, Societé de informatique médicale, Simed, Paris, 1991); c) cardiovascular parameters (heart rate, central venous pressure, invasive arterial pressure). MAIN RESULTS: The decay of propofol whole blood concentrations, distribution, redistribution and elimination half lives were similar in CRF and in control patients. On the contrary, significantly different in CRF patients were propofol blood concentrations from two to ten minutes following the induction dose (lower), the area under concentration- time curve (AUC) (smaller), the mean resident time (longer), the total body clearance (greater), the volumes of distribution at steady state and during the elimination phase (larger). The larger volumes of distribution are closely correlated with the significantly lower albumin concentrations in the uremic patients. An accelerated hepatic biotransformation is one of the possible explanations for the greater total body clearance of propofol in the uraemic patients: in fact an increased glucuronyltrasferase activity and glucuronoconjugation induced by phenols has been demonstrated in uraemia. On the other hand, large volumes of distribution are often associated with elevated total body clearance. The only significant change in the cardiovascular profile was a reduction of 17 +/- 8% of the systolic blood pressure one minute after the administration of the induction dose of propofol, whereas heart rate, arterial and central venous pressures were rather stable after intubation and at skin incision: proper vascular filling before the induction of anaesthesia has probably played a crucial role in maintaining hemodynamic stability. CONCLUSIONS: From the data gathered in this study, propofol can be considered a suitable anaesthetic agent for the induction of general anaesthesia in uraemic patients. In our opinion these data could constitute a basis for future protocols of total intravenous anaesthesia with propofol in uremic patients.

[Effectiveness and modality of continuous infusion administration of atracurium dibesylate]. / Attuabilità e modalità di somministrazione di atracurium dibesilato in infusione continua.

One-hundred and five patients with ASA I-II were scheduled for general surgery. Atracurium was the muscle-relaxant of choice. A bolus dose of atracurium (0.5 mg/kg-1) was administered immediately before thiopentone. After 15 minutes began the infusion of atracurium diluited in saline solution and administered through a simple infusion set. The neuromuscolar function was investigated evaluating the amplitude of response to TOF and DBS. This procedure proved to be safe, reliable and easily performed in every operating room.

Fentanyl pre-treatment does not affect the pharmacokinetic profile of an induction dose of propofol in adults.

The initial disposition of propofol was reported to change when the administration was preceded by fentanyl. The pharmacokinetic profile of the induction dose of propofol (2 mg kg-1 body weight) was studied in 20 ASA I patients randomly allocated to receive fentanyl 1.5 microgram kg-1 (n = 12) or not (n = 8). Anaesthesia was maintained with isoflurane in N2O/O2. Venous blood drawn from the contralateral arm was used to determine whole blood propofol concentrations. The mean propofol blood concentrations were comparable in the two groups and were best fitted by a three exponential equation in all the patients, conforming to a three-compartment open mammillary model. Distributions (T1/2 alpha) redistribution (T1/2(7)) and elimination (T1/2 beta half-lives were comparable in the groups, without significant differences in the total body clearance in the area under the time-concentration curve (zero-infinity) in the volume of distribution at steady-state, in the volume of distribution during the elimination phase or in the mean resident time. Our data support the conclusion that pretreatment with fentanyl does not affect the pharmacokinetic profile of the induction dose of propofol in ASA I patients.

Changes in circulating levels of atrial natriuretic factor (ANF) during orthotopic liver transplantation in humans.

Atrial natriuretic factor (ANF) is a 28 amino acid peptide secreted by the atrial cardiocytes. Clearance is via the lung (50%) and the liver (25%). The main stimulus to ANF secretion is atrial distension but vasoconstrictors, sympathetic stimulation, catecolamines and tachycardia are able to enhance its circulating blood levels. ANF blood concentrations were measured during orthotopic liver transplantation in six postnecrotic cirrhotic patients. Significant increases in ANF blood levels occurred at the end of the anhepatic phase (P < or = 0.02 vs baseline) associated with low cardiac filling pressures (P < or = 0.02 vs baseline) and increased systemic vascular resistances (P < or = 0.02 vs preanhepatic phase). Aldosterone blood levels showed a similar behaviour, increasing significantly (P > or = 0.001 vs baseline) at the end of the anhepatic phase. ANF fell after reperfusion of the graft and returned towards baseline values at the end of the procedure. Since most of the total body clearance of ANF is performed by the lungs, its sharp increase at the end of the anhepatic phase could be considered a counterregulatory response to vasoconstricting stimulation and to fluid-sparing mechanisms in the presence of relative hypovolaemia. Its decrease after reperfusion could be related to volume normalization and partly to the enhanced clearance performed by the newly grafted liver.

Somatomedin C (IGF I) plasma levels after orthotopic liver transplantation (OLT) in end-stage cirrhotic patients.

Insulin-like growth factors [IGF I and II or somatomedins (SMS)] are polypeptides chemically and biologically correlated with insulin. The main source of synthetic activity and secretion is the liver, although many other tissues have been demonstrated to synthesize SMS. In the circulation, they are not present in a free form, but are mostly bound to a specific carrier protein independently synthesized in the liver. Hepatic or extrahepatic storage organs have not been demonstrated; the half life of the SMS-binding protein complex is between 3 and 4. Synthesis of SMS is regulated by GH, insulin, thyroxine and nutrition (caloric and protein intake, and nitrogen balance). The role of corticosteroids is still a matter of debate: in patients treated with steroids SMS blood levels have been shown to be within normal limits, while biological activity has been demonstrated to be significantly reduced by SMS inhibitors, probably induced by corticosteroid therapy. The biological properties of SMS are related to their structural homology with insulin, and can be summarized as follows: A. Insulin-like activity (glucose oxidation, lipogenesis, glycogen synthesis, inhibition of lipolysis and glycogenolysis); B. Sulphation activity (incorporation of sulphate and leucine into glycosaminglycans of the cartilage); C. Stimulation of fibroblast multiplication; D. Amplification of other hormone activities (GH); E. Complementary anabolic activity with insulin. Low levels of SMS have been demonstrated in hypopituitarism (secondary) or in other diseases independent of GH reduced secretion (primary) such as malnutrition, malabsorption, acute or chronic liver failure and uraemia. Negative nitrogen balance, hypocaloric and/or low protein diets are usually correlated with low levels of SMS. Recently, Schalch et al. reported on the role of orthotopic liver transplantation (OLT) in normalizing SMS blood levels in a group of end-stage liver diseased patients. This preliminary paper deals with changes in IGF-I plasma levels (somatomedin C) in a group of patients affected by end-stage liver cirrhosis before and after OLT.