[Clinical assessment of a new anesthetic system: the Temel Supra (II)]

OBJECTIVES

To assess the clinical performance of a new anesthetic system developed to provide novel advantages in ventilating the anesthetized patient.

PATIENTS AND METHOD

The clinical performance of the Temel Supra was evaluated in 100 adult patients who were anesthetized and ventilated using the device.

RESULTS

The patients were adequately oxygenated and ventilated; no adverse events were observed. An open circuit, low flow, or closed circuit could be chosen freely. Ventilation was fully monitored: among the variables measured were rebreathed volume; leaks while the patient was connected; consumption of oxygen, nitrous oxide and anesthetic agents; and cardiac output (noninvasively).

CONCLUSIONS

Ventilation and gas exchange were satisfactory in all cases even though some patients developed considerable respiratory impedance. The monitoring of oxygen and other gases consumed and of carbon dioxide produced provided very valuable information about metabolism and pharmacokinetics. The noninvasive monitoring of cardiac output seems to us to be a useful feature for aiding hemodynamic control. The independence of the open and closed circuits means that expired gases do not pass through the canister when the open circuit is used, resulting in savings on soda lime for drying. During pressure-control ventilation, the system maintains a plateau to guarantee better distribution of inspired gases. Other important features are warnings, constant monitoring of leaks, the 100% efficacy of the circuit, and the low internal volume.

Superior gluteal nerve: safe area in hip surgery

Injuries to the superior gluteal nerve are very bad complications in hip surgery. An exact knowledge of its course may be helpful in avoiding such problems. Nineteen half pelvises from ten male and female adult cadavers were dissected. Dissections revealed that the nerve divided into two (89.48%) or three (10.52%) branches after leaving the pelvis. The more caudal branch was responsible for innervation of tensor fascia latae. The distance and the angle from the entry points of all branches of the superior gluteal nerve into the deep surface of the gluteus medium and minimus muscles to the mid-point of the superior border of the greater trochanter were measured. The branch that innerved the tensor fascia latae was also followed. These data were subjected to several statistical tests. Based on these findings, and in order to prevent nerve damage, we propose to define a 2-3 cm safe area above the great trochanter.

Rapid diagnosis of Staphylococcus aureus bacteremia using S. aureus PNA FISH

In the study presented here, the performance of the S. aureus PNA FISH assay was evaluated using 285 blood cultures (from 104 patients) that had gram-positive cocci resembling staphylococci on Gram stain. The new molecular test is based on a fluorescence in situ hybridization assay using peptide nucleic acid probes targeting Staphylococcus aureus 16S rRNA and is designed for the rapid identification of Staphylococcus aureus directly from positive blood cultures. The sensitivity, specificity, and positive and negative predictive values of the S. aureus PNA FISH for the rapid identification of Staphylococcus aureus directly from positive blood culture bottles were 100, 99.4, 99.2 and 100%, respectively.

Antitumoural action of L-733,060 on neuroblastoma and glioma cell lines

We have performed an in vitro study of the growth-inhibitory capacity of the potent and long-acting NK1 receptor antagonist L-733,060, at concentrations ranging from 2.5 microM to 20 microM, against the neuroblastoma cell line SKN-BE(2) and 10 microM to 25 microM for glioma cell line GAMG. Coulter counter was used to determine viable cell numbers, followed by application of the tetrazolium compound [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)2-(4-sulfophenyl)-2H-tetrazolium], inner salt colorimetric method to evaluate cell viability in this cytotoxicity assay. L-733,060 inhibited the growth of the two cell lines studied in a dose-dependent manner. The IC 50 values were 11.6 microM (30h) and 10.2 microM (72h) for SKN-BE(2); and 21.3 microM (48h) and 19.9 microM (96h) for GAMG. These findings indicate that the NK1 receptor antagonist L-733,060 acts as a broad-spectrum antitumoural agent. This new action, reported here for the first time, suggests that the NK1 receptor antagonist L-733,060 could be a promising therapeutic drug for the treatment of human neuroblastoma and human glioma.

[Characterization of the difference between filtered back projection and ordered subsets expectation maximization in spect images using the Wavelet Transform]

Efficiency of reconstruction algorithms is important to guarantee quality of Nuclear Medicine tomographic images. The algorithms belong to one of two types: analytical or statistical. The Filtered Back Projection (BP) algorithm belongs to the first group and the Ordered Subsets Expectation Maximization (OSEM) algorithm belongs to the second group. The aim of the present paper was to compare both algorithms by means of the Wavelet Transform (WT). This tool was selected because of its capability to divide the image into different frequency levels without losing information about their spatial position. The WT was applied on the Haar basis without decimation in order to compare matrixes of the same size. Attention was drawn to the relative presence of three typical perturbations: Poisson noise, annular artifacts that express a deficient correction to the planar uniformity and attenuation phenomenon. With these purposes, we studied homologue transversal slices of images of homogeneous distribution of activity. The OSEM algorithm not only greatly improves the filtering of the Poisson noise, but also diminishes the annular artifacts, mainly at the image zone that coincides with the rotation center. The intensity of the attenuation phenomenon was the same with both algorithms, except in the peripheral zone where OSEM showed a slightly higher activity than BP. These observations encourage our interest to continue applying the WT not only to identify the artifacts, but also to try to decrease their deleterious influence on Nuclear Medicine images.

Comparative immunolocalization of the plasma membrane calcium pump and calbindin D28K in chicken retina during embryonic development

The immunolocalization of the plasma membrane calcium pump (PMCA) was studied in 4-week-old chick retina in comparison with calbindin D28K (CaBP) immunostaining. We have demonstrated that the monoclonal anti-PMCA antibody SF10 from human erythrocyte plasma membrane cross-reacts with a Ca2+ pump epitope of the cells from the neural retina. The immunolocalization of both proteins was also studied during the embryonic development of the chicken retina. At age 4.5 days, the cells of the retina were faintly immunoreactive to PMCA and CaBP antibodies, but the lack of cellular aggregation and differentiation did not allow discrimination between the two proteins. A clear difference in the localization was seen from the tenth day of development through post-hatching with slight variation. PMCA localized mainly in the outer and inner plexiform layers, in some cells in the ganglion layer, in the nerve fiber layer and slightly in the photoreceptor cells. CaBP was intensely stained in cones, cone pedicles and some amacrine cells. The number of CaBP positive amacrine cells declined after hatching. A few ganglion cells and several nerve fibers were CaBP immunoreactive. The role of these proteins in the early stages of retinal development is unknown, but the results suggest that Ca2+ homeostasis in the retina is well regulated, probably to avoid excessive accumulation of Ca2+, which often leads to neurodegeneration.

Evaluation of two different cell lysis methods for releasing mycobacterial nucleic acids in the INNO-LiPA mycobacteria test

The INNO-LiPA Mycobacteria Test (Innogenetics, N.V., Belgium) is a PCR-based reverse hybridization assay for the simultaneous identification of several mycobacterial species. We evaluated two simplified lysis methods for mycobacterial DNA release for application in the INNO-LiPA Mycobacteria Test. The two methods were based on either (i) heat treatment or (ii) sonication. Both methods were performed directly on 45 positive liquid cultures (MB-BacT, BioMérieux, Marcy l'Etoile, France) containing 17 different mycobacterial species. These two simple lysis procedures demonstrated similar effectiveness (100%) to that recommended by the manufacturer. They also significantly shortened the time required for mycobacterial DNA release.

Inverted papilloma of the sphenoid sinus

Inverted nasosinusal papilloma is a benign tumor accounting for less than 4% of all nasal masses. The lesion originates in the mucosa lining the nasal cavities, the locations in decreasing order of frequency being the lateral wall of the nasal fossa, ethmoid sinus, and maxillary sinus; the sphenoid sinus is only rarely affected. Despite its benign histology, the tumor shows aggressive behavior and can be associated to carcinomas. Surgery is therefore indicated in such cases.

[Foam cell nephropathy in heterozygous female with Fabry's disease]

We describe the clinical and pathological characteristics of a 49 year-old heterozygous female carrier of Anderson-Fabry's disease. Light microscopy and ultrastructural study of a renal biopsy showed the presence of foam cell nephropathy and galactosylceramide deposits affecting podocytes, the parietal epithelium of Bowman's capsule and the distal tubular cells, endothelial cells and medullary interstitial elements. Retrospectively, the presence of storage disease was confirmed in a hysterectomy specimen obtained two years previously. Our observation shows that heterozygotes for this disorder can not only carry and transmit the disease but may also develop pathological deposits in various organs. A renal biopsy from these carriers allows precise identification of the disease, facilitates adequate genetic counseling and gives the option of enzyme replacement therapy in patients who have pathological deposits.

Physiological adaptations to exercise in people with spinal cord injury

The number of patients that suffer some type of spinal cord lesion in recent years are high and have increased because of factors such as traffic accidents. Although their life expectancy has increased, cardiovascular illnesses is one of the main causes of morbidity and mortality. Since the degree of physical fitness is an important factor regarding the risk of cardiovascular disease, the objective of the present study was to examine the global adaptation (cardiorespiratory, metabolic and thermoregulatory response) of the organism to exercise and the application of this data to the habitual practice of physical activity to improve state of health. A group of 42 patients with spinal injury, 85% of whom were paraplegic and the remaining 15% tetraplegic performed 42 exercise tests on a cycloergometer. Body temperature (tympanum, surface of the deltoids and surface of the back), metabolic parameters (plasma uric acid, glycemia, plasma lactate), cardiocirculatory adaptation (heart rate, blood pressure arm, blood pressure leg) and ventilatory adaptation (VO2, VCO2, fr Vt, VE) were monitored. Blood pressure in the arm, blood concentrations of lactate and ventilatory parameters showed an evolution statistically dependent on the work to which the subject was submitted. Heart rate showed a statistically significant correlation with the ventilatory parameters and work load. The proportional response of the cardioventilatory parameters to the increase in the work load allowed us to evaluate the repercussion of a given exercise and thus avoid exercise of an excessive intensity that could produce cardiocirculatory changes that might entail an added risk. Heart rate presents an excellent correlation, shown in this work, with the oxygen consumption and could therefore be used to quantify the cardiorespiratory and metabolic repercussion of the exercise carried out. Furthermore, this quantification may allow for the adaptation of exercise intensity to the patient thus improving the results obtained from the practice of exercise that has been proven so necessary in these patients.

Influence of leptin levels and body weight in survival of children with sepsis

High levels of serum leptin (LPT) were reported in adult patients with sepsis and a protective role was suggested. LPT was determined in sera from 55 children with severe sepsis at admission (0 h), 6, 24 and 48 h. LPT levels were higher at 0 h than at 24 h (2.80 vs 1.61 ng/ml; p = 0.009) and a negative correlation was found with IL-13 (p = 0.009), and granulocyte counts (p = 0.035), but not with other factors. Infants younger than 12 mo of age had higher LPT levels than older infants (5.88 vs 2.38 ng/ml; p = 0.0005). The increase in LPT levels was higher in non-survivor patients than in survivors, with a maximum difference at 24 h (5.30 vs 1.45 ng/ml; p = 0.0042). However, LPT levels were not associated with shock, multiorgan failure or the severity score. Children who died showed higher percentiles of weight than survivors (p = 0.025). A subgroup with higher LPT (> Pc75) included mainly patients with weight > Pc50 (p = 0.0065), low IL-13 levels (p = 0.007) and low granulocyte counts (p = 0.013), Neisseria meningitidis B being the most frequently isolated germ (p = 0.022).

CONCLUSION

Using a model of severe infection, mainly meningococcal, in young children (median 3 y 6 mo old), it was not possible to confirm previous results in adults. A general protective role for LPT in sepsis seems unlikely.

Posterior fossa subdural hematoma mimicking intracerebellar hemorrhage

Subdural hematomas of the posterior fossa are very rare and most cases are related to head injury. The influence of anticoagulation in cases of spontaneous development is well known. Although diagnosis is easily achieved by CT sean, atypical forms may lead to the wrong diagnosis of cerebellar hematoma. We present a case of a posterior fossa acute subdural hematoma occurring in an anticoagulated patient who was preoperatively misdiagnosed as an intracerebellar hemorrhage.

LDL-cholesterol/apolipoprotein B ratio is a good predictor of LDL phenotype B in type 2 diabetes

LDL phenotype B is a component of diabetic dyslipidaemia, but its diagnosis is cumbersome. Our aim was to find easily available markers of phenotype B in a group of type 2 diabetic subjects. We studied 123 type 2 diabetic patients (67.5% male, aged 59.3+/-10.1 years, mean HbA1c 7.4%). Clinical features and fasting total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol (LDLc, using Friedewald's equation and an alternative formula), apolipoprotein B (apoB), lipoprotein (a) and LDL particle size (on gradient polyacrylamide gel electrophoresis) were assessed. Patients with phenotypes A (predominant LDL size > or =25.5 nm) and B (<25.5 nm) were compared, and regression analysis was performed to find the best markers of LDL particle. Cut-off points were obtained and evaluated as predictors of phenotype B (kappa index). Patients with phenotype B (36%) showed higher total cholesterol, triglyceride and apolipoprotein B, and lower HDL cholesterol and LDLc/apoB ratio. Triglyceride was the best predictor of LDL particle size (r=-0.632, p<0.01), but an LDLc/apoB ratio below 1.297 mmol/g detected phenotype B best (sensitivity 65.9%, specificity 92.4%, kappa=0.611). Although triglyceride concentration is the best predictor of LDL size in type 2 diabetes, LDLcholesterol/apolipoproteinB ratio is the best tool to detect phenotype B.

[Dexmedetomidine, a promising drug]

Surgical patients and others admitted to recovery and intensive care units require sedation and pain therapy, for which a range of pharmaceuticals is available. Their use is more or less widespread, but other drugs, such as dexmedetomidine, have been and continue to be studied for application in such patients. Dexmedetomidine, a compound derived from imidazole, has a high affinity for the alpha-2 adrenoreceptor, on which it acts as a potent agonist. A large number of laboratory and animal studies have been performed, as have clinical trials enrolling healthy volunteers or patients with the aim of shedding shed light on the main pharmacological features of dexmedetomidine. As a result, dexmedetomidine is known to have sedative, hypnotic and analgesic properties. It diminishes the need for other anesthetics and sympathicolytics, and it reduces catecholamine release. Controlled clinical trials have looked at the use of dexmedetomidine in patients who require sedation and analgesia in postoperative intensive care units. Research shows that dexmedetomidine lowers the need both for other sedatives, such as propofol or midazolam, and for analgesic morphine. Moreover, its effect on ventilation is scarce. Dexmedetomidine is presently distributed in the United States but not in the European Union. The aim of this review was to outline the main pharmacological properties of dexmedetomidine, including its pharmacokinetics and pharmacodynamics, to give an overall view of this promising drug.

[Therapeutic efficacy of GM-CSF in pulmonary alveolar proteinosis]

Pulmonary alveolar proteinosis is a rare disease characterized by the deposit of lipid-rich proteinaceous material in alveolar spaces. The only effective treatment known to date has been periodic alveolar lavage, a technique that is laborious and requires that the patient be under general anesthesia, with selective endotracheal-bronchial intubation. Complications are not unknown. Progress in our understandint of the pathogenesis of pulmonary alveolar proteinosis has shown it to be related to changes it to be related to changes in alveolar macrophagocytic capability. We describe a patient in whom 8 weeks of subdermal GM-CSF treatment led to significant clinical, radiologic and lung function improvement.

[Incidence of postoperative shivering in relation to the time of sevoflurane discontinuation]

OBJECTIVES

We aimed to determine whether early termination of sevoflurane administration lowers the incidence of postanesthetic shivering.

MATERIAL AND METHODS

Eighty ASA I-III patients were randomized to two groups of 40 (Group A and Group B). All were premedicated with oral bromazepam. Fentanyl (2 micrograms/Kg), propofol (2.5 mg/Kg) and atracurium (0.5 mg/Kg) were used for induction. Anesthesia was maintained with sevoflurane in 60% N2O in oxygen at 1 maximum alveolar concentration, with boluses of fentanyl and atracurium on demand. Sevoflurane administration was terminated 30 minutes before awakening in group A and 10 minutes before awakening in group B. After termination, 60% N2O in oxygen was used in both groups. Mean blood pressure, heart rate and peripheral and core temperatures were measured at 5 minutes intervals during surgery. Postoperative shivering was recorded until one hour after awakening.

RESULTS

Patient characteristics and duration of anesthesia were similar in both groups. The incidence of shivering was significantly lower in group A (4%) than in group B (57%). No significant differences were observed in other variables.

CONCLUSIONS

The important observation in this study was that the incidence of postoperative shivering in group A was lower than in group B and lower than the incidences reported in other similar studies.

[Factors associated with hospital mortality in patients admitted to the intensive care unit in Colombia]

OBJECTIVES

To describe the demographic features, reasons for hospital admission and factors associated with hospital mortality in patients admitted to intensive care in Colombia.

METHOD

A cohort study of patients admitted to intensive care units (ICUs). Of 89 ICUs identified in Colombia, 20 in ten cities were invited to gather information on 200 consecutive patients admitted to each ICU.

RESULTS

Three thousand sixty-six patient cases were available for analysis. The mean age was 53 years and 43% were women (men vs. women, p < 0.001). The most frequent cause of admission was medical (63.9%), acute myocardial infarction patients (7.1%) comprising the largest group. Severity of disease measured as APACHE II and III was a mean 14.0 (SD 6.9) and 48.3 (SD 23.5), respectively. Multivariate analysis, independent of adjustment for severity (APACHE II or III), showed that the factors associated with hospital death were the need for mechanical ventilation, pupillary response, transfer from a medical ward, and management by the ICU team prior to admission (p < 0.01).

CONCLUSION

The most common reason for admission to an ICU in Colombia was myocardial infarction. Besides severity of disease, other variables related to medical care in Colombia are associated with hospital mortality, such as invasive ventilation. Although these variables may be artifacts related to disease severity, they are more likely to be related to quality of care.

[Pure red cell aplasia in a lung transplant patient]

Aplastic anemia secondary to infection by parvovirus B19 is normally an extremely rare problem in patients with no prior history. However, the presence of certain risks, such as receiving chronic immunosuppressant therapy, may facilitate its appearance. Very few cases have been published concerning red cell aplasia due to parvovirus B19 infection in patients receiving a transplanted lung. We report the case of a 24-year-old woman with cystic fibrosis who had received a double lung transplant. The patient developed red cell aplasia secondary to parvovirus B19 infection; severe anemia requiring multiple transfusions. Five days of intravenous immunoglobulin therapy resolved the anemia. We discuss the difficulty of serological diagnosis in such cases, the importance of using techniques that identify the virus and taking measures that may prevent recurrence.

Oral leishmaniasis in a HIV-positive patient. Report of a case involving the palate

Leishmaniasis is a parasitic disease caused by a protozoon (Leishmania), with different clinical forms that are endemic in certain countries. The association of this disease in patients who are seropositive to human immunodeficiency virus (HIV) has recently been described. Leishmaniasis can develop in any stage of HIV infection, although the clinical manifestations - and hence the diagnosis - tend to coincide with the periods of maximum immune depression. We present the case of a HIV-positive, ex-intravenous drug abuser (in stage B2 of the CDC, 1992) with concomitant hepatitis C infection who presented with palatinal pain and bleeding for the past 2 months. Exploration revealed a vegetating tumoration of the hard palate. Hematoxylin-eosin and Giemsa staining of the biopsy confirmed the diagnosis of leishmaniasis. The definitive diagnosis was mucocutaneous leishmaniasis (MCL), for a bone marrow aspirate proved negative, and no further lesions could be established. The patient was treated with meglumine antimoniate (Glucantime), followed by improvement of the lesions.

[Study of Mycobacterium bovis in milk using bacteriological methods and the polymerase chain reaction]

The frequency of Mycobacterium bovis detection in milk samples obtained from infected animals was explored in an intensive dairy area in Argentina. To this end, an "in house" polymerase chain reaction (PCR) method was developed using Mycobacterium tuberculosis Complex specific INS1-INS2 primers, and its performance was compared with that of bacteriological methods. The decontamination procedures previous to culture reduced M. bovis viability. The pathogen was identified in milk samples from 1 of 143 infected cows and in none of 43 uninfected ones. Even though PCR sensitivity was found to be 2-20 times higher than that of bacteriology in experimentally inoculated milk samples, all 186 field samples resulted negative by PCR, including the bacteriologically-confirmed one. In spite of the high prevalence of bovine tuberculosis in Argentinian dairy herds, the detection of M. bovis in milk is an unusual finding.

Apo(B)-dependent dyslipidemic phenotypes in type 1 diabetic patients

BACKGROUND

The prevalence of apo(B)-dependent dyslipidemic phenotypes, which are associated with cardiovascular disease, is increased in normocholesterolemic type 2 diabetic patients. Our aim was to determine the impact of including apo(B) in the evaluation of normocholesterolemic type 1 diabetic patients.

METHODS

A total of 123 type 1 diabetic patients (47% male, age 36.6+/-12.5 years) were included. The apo(B) cut-off point (1.14 g/l) was obtained from a group of 53 normolipidemic control subjects of similar age and gender distribution; for low density lipoprotein cholesterol (LDLc), triglycerides, and high density lipoprotein cholesterol (HDLc), we used the cut-off points recommended by the National Cholesterol Education Program. LDLc was determined by ultracentrifugation or Friedewald's equation, depending on triglyceride concentrations, and apo(B) by immunoturbidimetry.

RESULTS

A total of 113 (92%) type 1 diabetic patients were normocholesterolemic, and 13% of these were dyslipidemic. The frequency of hyperapo(B) was similar in normocholesterolemic patients and controls (6.2 vs. 9.4%, respectively). Diabetic patients with hyperapo(B) had poorer glycemic control, higher total cholesterol, triglycerides, and LDLc, and a lower HDLc and LDLc/apo(B) ratio.

CONCLUSIONS

Unlike type 2 diabetes, type 1 diabetes is not associated with an increased prevalence of hyperapo(B)-dependent dyslipidemic phenotypes. Thus, only in patients with poor glycemic control who display other components of diabetic dyslipidemia, typical for type 2 diabetes, does determining apo(B) concentrations provide additional information in type 1 diabetes.