Laparoendoscopic Single-Site Surgery in Kidney Surgery: Clinical Experience and Future Perspectives

Laparoscopic surgery of the upper urinary tract has reduced the morbidity related to large abdominal incisions and has resulted in significant advantages over open surgery. Nevertheless, the pursuit for even more minimally invasive alternatives to laparoscopy has led to the concept of scarless surgery and the approach of laparoendoscopic single-site surgery (LESS). LESS is currently a feasible approach for the majority of kidney surgical procedures, and there is intense debate regarding its efficiency and advantages. In the present review of the literature, the current status of upper urinary LESS and its advantages and disadvantages, as well the technological and technical evolution, are presented.     

A telemetry system designed for use with a conductive walkway: description and validation

We present a telemetry system developed for use with a conductive walkway. A transmitter, a receiver, a conductive walkway and a PC with the appropriate software form the entire system, which is used for the assessment of the temporal parameters of gait and the gait speed. The technique is easy to use in routine clinical practice, easily reproducible and commercially available for research laboratories with restricted financial support. The telemetry system was found to be sufficiently accurate and repeatable, and was validated with a group of 20 healthy male adults (mean age, 34 years). The present results are similar to those reported in the literature for an alike group of subjects. Received: 17 January 2001/Accepted in revised form: 15 May 2001     

Variations in alveolar cell populations, lymphocyte subsets and NK-cells in different stages of active pulmonary sarcoidosis

BACKGROUND: The type and mode of presentation of pulmonary sarcoidosis (radiologic stage, activity) influence alveolar lymphocyte number and subsets as well as other inflammatory cells. AIM: To investigate the variations in alveolar cells, lymphocyte subsets and NK-cells in different radiological stages of active pulmonary sarcoidosis. METHODS: 85 untreated, newly diagnosed patients (32 male, 53 female), median age 47.2+/-14.7 years were investigated. Patients were classified into chest x-ray stages (33 stage I, 27 stage II, 14 stage III and 11 stage IV disease). Bronchoalveolar lavage was performed with 4 portions of 50 mL. Total cells and cell differentials were counted, while CD3+, CD4+, CD8+, CD19+, CD3-CD16/56+ (NK-cells) and CD3+CD16/56+ (NKT-cells) were determined by flow cytometry. Results: Lymphocytosis was high in all stages. Significant differences were found in: a) CD4 between stages I and II and I and IV. b) CD8 between stages I and IV and c) NK and NKT cells between stages I and III. CONCLUSIONS: Variations were observed in alveolar cells and lymphocyte subsets in different stages of pulmonary sarcoidosis. Cells exhibiting cytotoxic activity were increased with stage progression, CD8 from stage I to IV, NK and NKT cells from stage I to III. These cells may be involved in the inflammatory process regulating granuloma formation.     

Dialysate magnesium level and blood pressure

BACKGROUND: We investigated the way dialysate magnesium (dMg) concentrations could affect blood pressure (BP) during hemodialysis (HD). METHODS: Eight HD patients underwent four midweek HD treatments consecutively, using, during each four-hour HD session, one of the following four dialysate formulations, in randomized order, which differed only with regard to dMg and dialysate calcium (dCa) concentrations (in mmol/L): 0.75 dMg, 1.75 dCa (group I); 0.25 dMg, 1.75 dCa (group II); 0.75 dMg, 1.25 dCa (group III); 0.25 dMg, 1.25 dCa (group IV). Before HD and at four 60-minute intervals during the HD sessions, BP and noninvasive measurements of cardiac index (CI) were obtained. Additionally, 14 HD patients were treated for four weeks with 0.5 mmol/L dMg, followed by four weeks with 0.25 mmol/L dMg, and another four weeks with 0.75 mmol/L dMg, in random order. In all treatments dCa was 1.25 mmol/L. BP and symptoms were recorded during each HD session. RESULTS: Mean arterial pressure (MAP) decreased to a significantly (P < 0.05) greater extent in group IV compared to the other groups. This substantial drop in MAP by 15.2% in group IV, paralleled by a 12.1% and 17% drop in CI and stroke index, respectively, was not seen in group II, despite comparable reductions in intradialytic serum Mg (sMg) of about 35% in both groups. In groups I and III, the increase in sMg by 2% did not compromise BP via vasodilatation. In the second study, treatment with 0.75 mmol/L dMg was superior to the other two treatments regarding intradialytic morbidity (P < 0.001) and BP stability (P < 0.05). CONCLUSION: We (1) identified a dialysis solution containing 0.25 mmol/L Mg and 1.25 mmol/L Ca as a major cause of intradialytic hypotension (IDH) due to an impairment of myocardial contractility, and (2) showed that increasing dMg level to 0.75 mmol/L could prevent IDH frequently seen with the use of 1.25 mmol/L dCa. Thus, manipulating dMg levels independently or in concert with dCa levels might have important implications with regard to dialysis tolerance.     

Quantitative multichannel EEG measure predicting the optimal weaning from ventilator in ICU patients with acute respiratory failure.

OBJECTIVE: The objective of this study was to develop a novel quantitative multichannel EEG (qEEG) based analysis method, called Global Field Damping Time (GFDT), in order to detect potential EEG changes of patients admitted to the ICU with acute respiratory failure, and correlate them to the patients' recovery outcome predicting the optimal time-point to disconnect the patient from mechanical ventilation. METHODS: Twenty-nine adult patients with acute respiratory failure out of 98 admitted to the Intensive Care Unit of Saint Paul General Hospital were enrolled, and among them only 15 completed the study. The patients were classified in 3 groups according to their outcome after 3 months follow-up. The patients were intubated with fraction of inspired oxygen (FiO2) of 100%. Neurological Deficit Scores (NDS) were measured 24 h after intubation to assess patients' neurological condition. Twenty-four hours after patient's intubation, FiO2 was decreased to 40% (weaning session), followed by a 5 min early recovery session, a 5 min recovery 1 session and a 5 min recovery 2 session. EEG recordings were performed during this experimental procedure. Multichannel EEG segments were processed and fitted into a multivariate autoregressive (mAR) model, and single channel EEG segments into a scalar autoregressive (sAR) model. The mAR and the sAR models of arbitrary order p were decomposed into mp and p oscillators and relaxators, respectively. Damping time of each oscillator and each relaxator, and the Global Field Damping Time (GFDT) as a weighted damping time were estimated for both mAR and sAR models. RESULTS: A statistically significant increase of mAR model's GFDT during the weaning session was observed in the subjects of all groups. Comparing the 3 patients' groups, statistically significant differences for mAR model's GFDT were observed for the weaning and early recovery session. Linear regression analysis between NDS and mean mAR model's GFDT showed statistical significance during weaning session, early recovery session, and recovery 1 session. There was no statistical significance for SaO2 in the regression analysis with NDS. The sAR model's GFDT presented worst results in comparison with the mAR modelling GFDT in the identification of hypoxic conditions during weaning session and in the discrimination of patients with acute respiratory failure according to their neurological outcome. CONCLUSIONS: Global Field Damping Time as correlated to the patients' neurological outcome appears to be a simple, compact, and substantial novel indicator of cerebral hypoxia and a potential predictor of the optimal time-point to disconnect the patient from the ventilator. SIGNIFICANCE: Quantitative EEG seems to be an important tool for ICU clinicians assisting them to decide for the patients' optimal time-point to disconnect the patient from the ventilator.