Predicting personalised and progressive adaptive dose escalation to gross tumour volume using knowledge-based planning models for inoperable advanced-stage non-small cell lung cancer patients treated with volumetric modulated arc therapy

OBJECTIVES

Increased radiation doses could improve local control and overall survival of lung cancer patients, however, this could be challenging without exceeding organs at risk (OAR) dose constraints especially for patients with advanced-stage disease. Increasing OAR doses could reduce the therapeutic ratio and quality of life. It is therefore important to investigate methods to increase the dose to target volume without exceeding OAR dose constraints.

METHODS

Gross tumour volume (GTV) was contoured on synthetic computerised tomography (sCT) datasets produced using the Velocity adaptive radiotherapy software for eleven patients. The fractions where GTV volume decreased compared to that prior to radiotherapy (reference plan) were considered for personalised progressive dose escalation. The dose to the adapted GTV (GTVAdaptive) was increased until OAR doses were affected (as compared to the original clinical plan). Planning target volume (PTV) coverage was maintained for all plans. Doses were also escalated to the reference plan (GTVClinical) using the same method. Adapted, dose-escalated, plans were combined to estimate accumulated dose, D99 (dose to 99%) of GTVAdapted, PTV D99 and OAR doses and compared with those in the original clinical plans. Knowledge-based planning (KBP) model was developed to predict D99 of the adapted GTV with OAR doses and PTV coverage kept similar to the original clinical plans; prediction accuracy and model verification were performed using further data sets.

RESULTS

Compared to the original clinical plan, dose to GTV was significantly increased without exceeding OAR doses. Adaptive dose-escalation increased the average D99 to GTVAdaptive by 15.1Gy and 8.7Gy compared to the clinical plans. The KBP models were verified and demonstrated prediction accuracy of 0.4% and 0.7% respectively.

CONCLUSION

Progressive adaptive dose escalation can significantly increase the dose to GTV without increasing OAR doses or compromising dose to microscopic disease. This may increase overall survival without increasing toxicities.

Central nervous system relapse in high-risk stage 4 neuroblastoma: The HR-NBL1/SIOPEN trial experience

BACKGROUND

There is rising concern on the impact of new strategies, such as high-dose chemotherapy (HDC) and immunotherapy, on the pattern of relapse in high-risk neuroblastoma (HR-NBL). Our aim is to evaluate the incidence and identify risk factors for first recurrence in the central nervous system (CNS) in HR-NBL.

PATIENTS AND METHODS

Data from patients with stage 4V HR-NBL included from February 2002 to June 2015 in the prospective HR-NBL trial of the European International Society of Pediatric Oncology Neuroblastoma Group were analysed. Characteristics at diagnosis, treatment and the pattern of first relapse were studied. CNS imaging at relapse was centrally reviewed.

RESULTS

The 1977 included patients had a median age of 3 years (1 day-20 years); 1163 were boys. Among the 1161 first relapses, 53 were in the CNS, with an overall incidence of 2.7%, representing 6.2% of all metastatic relapses. One- and three-year post-relapse overall survival was 25 ± 6% and 8 ± 4%, respectively. Higher risk of CNS recurrence was associated with female sex (hazard ratio [HR] = 2.0 [95% confidence interval {CI}: 1.1-3.5]; P = 0.016), MYCN-amplification (HR = 2.4 [95% CI: 1.2-4.4]; P = 0.008), liver (HR = 2.5 [95% CI: 1.2-5.1]; P = 0.01) or >1 metastatic compartment involvement (HR = 7.1 [95% CI: 1.0-48.4]; P = 0.047) at diagnosis. Neither HDC nor immunotherapy was associated with higher risk of CNS recurrence. Stable incidence of CNS relapse was reported over time.

CONCLUSIONS

The risk of CNS recurrence is linked to both patient and disease characteristics, with neither impact of HDC nor immunotherapy. These findings support the current treatment strategy and do not justify a CNS prophylactic treatment.

Opioid receptors expression in the skin of haemodialysis patients suffering from uraemic pruritus

BACKGROUND

Uraemic pruritus is a common symptom in patients with chronic kidney disease undergoing haemodialysis (HD) treatment. Etiopathogenesis of uraemic pruritus is complex and not fully explained, but there are reports indicating a possible role of peripheral opioid system in its pathomechanism.

OBJECTIVES

This study was undertaken to analyse the expression of mu- and kappa-opioid receptors in the skin of HD patients with and without uraemic pruritus.

METHODS

Forty patients suffering from chronic kidney disease, treated with haemodialysis (21 pruritic and 19 non-pruritic), were included. The expression of mu- and kappa-opioid receptors in their skin was evaluated with immunohistochemistry.

RESULTS

The significant (P < 0.02) decrease in kappa-opioid receptor expression was shown in the skin of pruritic patients in comparison with the skin of those without itch (1.07 ± 0.62 and 1.66 ± 0.85, respectively). Moreover, there was a significant negative correlation between intensity of pruritus and expression of kappa-opioid receptors (r = -0.63, P = 0.002). There was no difference in the expression of mu-opioid receptor expression in the skin of pruritic and non-pruritic HD patients.

CONCLUSIONS

This study indicates that changes in peripheral opioid system may play an important role in the uraemic itch pathogenesis and that future studies are necessary to fully understand this mechanism.

Jumping Height Does Not Increase in Well Trained Volleyball Players After Transcutaneous Spinal Direct Current Stimulation

Transcutaneous spinal direct current stimulation (tsDCS) increases corticospinal and spinal reflex excitability, and may be a new tool for increasing muscle explosive performance in sports training. The aim of the study was to evaluate whether tsDCS can enhance jumping ability in trained humans practicing volleyball. Twenty eight participants completed the study, including 21 men and 7 women. We investigated the effects of a single 15-minute session of sham, anodal, and cathodal tsDCS over spine and shoulder on repeated counter movement jump (CMJ) and squat jump (SJ) performance at 0, 30 and 60 min post-stimulation. The order of SJs and CMJs sets in each session was randomized. Each SJ and CMJ set consisted of 3 jumps. The break between each attempt was 1 min and the interval between the sets was 3 min. Two-way repeated measures ANOVA did not show effect of time, nor stimulation method, nor stimulation method × time interactions on SJ (time: F_(1.8,_142.1) = 1.054; p = 0.346, stimulation: F₍₂,₇₈₎ = 0.019; p = 0.981, stimulation × time: F_(3.6,_142.1) = 0.725; p = 0.564) or CMJ (time: F_(1.8,_140.9) = 2.092; p = 0.132, stimulation: F₍₂,₇₈₎ = 0.005; p = 0.995, stimulation × time: F_(3.6,_140.9) = 0.517; p = 0.705) performance. Single session of tsDCS over spine and shoulder does not increase jumping height in well-trained volleyball players. This is an important finding for coaches and strength conditioning professionals for understanding the practical utility of tsDCS for enhancing muscular explosiveness.

The use of testicular prostheses in boys

Lack of the testis is an important factor in psycho-sexual development of the boys, and implantation of the prosthesis plays a very essential role in the treatment of that group of patients. Currently there are no standards regarding when prosthesis should be implanted, and which access is connected with minimal rates of complications. We present our experience of primary prosthesis implantations in boys treated in our department.From 2000 to 2014, primary implantation of the testicular prosthesis was performed in 290 boys. The early and late post-operative complications and long-term therapeutic results were analyzed, considering age at the time of implantation, the time between the initial operation and implantation of the prosthesis, and the surgical approach.Best results were observed in 267 patients and bad outcome in 23 patients. Prosthesis implantation in young boys operated within the first three years of life or during the first year after primary surgery was connected with statistically fewer complications (P = .002 and P < .05, respectively). Supra-scrotal access was connected with the lowest rate of complications (P = .01).Long-term therapeutic results in boys with testicular prostheses were good in the majority of cases. Implantation of the first prosthesis should be performed early between 1 and 3 years of life in boys with lack of the testis. Implantation of a prosthesis should also be performed within 1 year after removing of testis or during orchiectomy. Supra-scrotal access should be chosen for testicular prosthesis implantation due to the best long-term results.

Evaluation of Single-Chip, Real-Time Tomographic Data Processing on FPGA SoC Devices

A novel approach to tomographic data processing has been developed and evaluated using the Jagiellonian positron emission tomography scanner as an example. We propose a system in which there is no need for powerful, local to the scanner processing facility, capable to reconstruct images on the fly. Instead, we introduce a field programmable gate array system-on-chip platform connected directly to data streams coming from the scanner, which can perform event building, filtering, coincidence search, and region-of-response reconstruction by the programmable logic and visualization by the integrated processors. The platform significantly reduces data volume converting raw data to a list-mode representation, while generating visualization on the fly.

The relationship between jumping performance, isokinetic strength and dynamic postural control in elite youth soccer players

BACKGROUND

The aim of this study was to investigate the relationship between vertical jumping performance, isokinetic strength of knee extensors/flexors, and postural priority and to describe a multiple regression model that accounts for the effects of selected parameters of isokinetic strength and postural priority on vertical jumping performance.

METHODS

Thirty-one professional male soccer players, aged from 17 to 20 years, participated in this study (age, mean±SD: 18.6±1.26 years; height: 1.78±0.74 m and weight: 73.1±6.77 kg). The correlations between isokinetic knee strength, jumping performance, and postural control were evaluated using the Pearson correlation coefficient. A linear regression model was used to evaluate the effect of hamstrings and quadriceps peak torque of both legs at 60º·s-1, total work of both legs at 240º·s-1, and postural priority on jumping performance.

RESULTS

The peak torque of right leg knee flexor (quadriceps) muscles, evaluated at 60º·s-1 speed, showed correlations with counter movement jump, 30 second jumping and squat jump (P=0.005, P=0.003, and P=0.007, respectively). We also observed a strong relationship between counter movement jump and 30 second jumping and peak torque of left leg evaluated at the same speed of 60º·s-1 (P=0.26 and P=0.22, respectively). No significant correlations were found between any of the jumping tests and peak torque of knee extensors of both legs at 60º·s-1. For the 30 second jumping test, it appears that jumping endurance has a significant relationship with total work of knee flexors for right and left legs at 240º·s-1.

CONCLUSIONS

The results of this study demonstrate practical implications for soccer performance, but further exploration is required.

A comparison of BIS recordings during propofol-based total intravenous anaesthesia and sevoflurane-based inhalational anaesthesia in obese patients

BACKGROUND

Intraoperative awareness is a rarely occurring phenomenon. Obesity is considered as one of the factors increasing the probability of intraoperative awareness due to problems with the dosing of anaesthetics. In a randomized prospective study we compared bispectral index (BIS) recordings during propofol-based total intravenous anaesthesia (TIVA) and sevoflurane-based inhalation anaesthesia in morbidly obese patients as a sign of possible intraoperative awareness.

METHODS

120 morbidly obese patients were randomly allocated into two subgroups: TIVA or SEVO. Propofol TIVA was performed following the Servin formula, while sevoflurane was administered based on the age of the patients. The physician administering anaesthesia was blinded to the BIS recordings while the evaluation of the depth of anaesthesia was conducted based on the clinical symptoms of adequate anaesthesia. BIS recordings were evaluated for periods of BIS > 60. Blinded structured interviews were conducted 2 hours after anaesthesia was administrated.

RESULTS

The incidence of BIS > 60 occurred in 90% vs. 91.67% of patients while the mean duration of periods of BIS > 60 was 13.74 ± 21.74% vs. 14.21 ± 18.78% of the duration of anaesthesia in TIVA and SEVO groups, respectively (P > 0.05). There was no correlation between the BMI value and the duration of elevated BIS values observed during anaesthesia in both studied methods of anaesthesia, nor between the total time of anaesthesia and the duration of elevated BIS values above 60 in this study. No patient complained of intraoperative awareness when asked in the post-operative period, probably due to the administration of midasolam.

CONCLUSIONS

Although the incidence of BIS > 60 are very common in obese patients, true awareness during anaesthesia infrequent in this group of patients despite the type of anaesthesia, whether intravenous or inhalation.

The degree of intubation difficulties and the frequency of complications in obese patients at the Hospital Emergency Department and the Intensive Care Unit: Case-control study

The intubation difficulties in obese patients are not a new problem. They may result from an accumulation of fat in the oral cavity and cheeks. A thick tongue is also a significant factor. The literature reports that some tests to determine the intubation difficulties in obese people may be unreliable. The observed predictors of difficult intubation were the thyromental and sternomental distance and the intubation difficulty scale: FRONT score.The aim of this study was to assess the degree of difficult intubation in obese patients by the parameters such as the thyromental and sternomental distance. The authors also tried to evaluate the frequency of the guidewire usage and the number of intubation attempts in obese patients in the research sample.The study included the group of 153 patients intubated in prehospital conditions. The research was conducted in 3 clinical centers receiving patients from prehospital care. Among the members of the research sample, obese patients with body mass index >35 were selected and evaluated for various predictors of intubation difficulties. Quantitative analysis of differences in the incidence of the variables was assessed using the chi-squared test for P < 0.05. Analyses were performed in STATISTICA.Complications such as postintubation hematomas were more frequent in obese patients of the research sample. The frequency of the guidewire usage observed in that group was also higher. As anticipated by the adopted predictors, most of the obese patients were classified as difficult to intubate.There is a correlation between the occurrence of injuries and the prevalence of obesity in the research sample and the same dependency has been demonstrated in the issue concerning the use of the guidewire. Although the majority of predictors indicated patients with intubation difficulties, many predictors could show falsely positive results. The greater amount of intubation attempts was observed in obese patients. Further studies devoted to explain those correlations would be needed.

Time resolution of the plastic scintillator strips with matrix photomultiplier readout for J-PET tomograph

Recent tests of a single module of the Jagiellonian Positron Emission Tomography system (J-PET) consisting of 30 cm long plastic scintillator strips have proven its applicability for the detection of annihilation quanta (0.511 MeV) with a coincidence resolving time (CRT) of 0.266 ns. The achieved resolution is almost by a factor of two better with respect to the current TOF-PET detectors and it can still be improved since, as it is shown in this article, the intrinsic limit of time resolution for the determination of time of the interaction of 0.511 MeV gamma quanta in plastic scintillators is much lower. As the major point of the article, a method allowing to record timestamps of several photons, at two ends of the scintillator strip, by means of matrix of silicon photomultipliers (SiPM) is introduced. As a result of simulations, conducted with the number of SiPM varying from 4 to 42, it is shown that the improvement of timing resolution saturates with the growing number of photomultipliers, and that the [Formula: see text] configuration at two ends allowing to read twenty timestamps, constitutes an optimal solution. The conducted simulations accounted for the emission time distribution, photon transport and absorption inside the scintillator, as well as quantum efficiency and transit time spread of photosensors, and were checked based on the experimental results. Application of the [Formula: see text] matrix of SiPM allows for achieving the coincidence resolving time in positron emission tomography of [Formula: see text]0.170 ns for 15 cm axial field-of-view (AFOV) and [Formula: see text]0.365 ns for 100 cm AFOV. The results open perspectives for construction of a cost-effective TOF-PET scanner with significantly better TOF resolution and larger AFOV with respect to the current TOF-PET modalities.

[Kidney cancer with venal thrombus-principles of menagement]

Frequency of renal cell carcinoma with tumor thrombus may reach up to 30% of cases. Epidemiologic data show that tumor thrombus by itself is not negative predictive factor. Meticulous preparation by analisis of high quality imaging, acurate preoperative patient and team preparation enables to make complete thrombus resection. In our analisis we propouse rules of holistic treatment for patients suffering from renal cell carcinoma with tumor thrombus. Applying of these rules results in satisfactory long term results.

A feasibility study of ortho-positronium decays measurement with the J-PET scanner based on plastic scintillators

We present a study of the application of the Jagiellonian positron emission tomograph (J-PET) for the registration of gamma quanta from decays of ortho-positronium (o-Ps). The J-PET is the first positron emission tomography scanner based on organic scintillators in contrast to all current PET scanners based on inorganic crystals. Monte Carlo simulations show that the J-PET as an axially symmetric and high acceptance scanner can be used as a multi-purpose detector well suited to pursue research including e.g. tests of discrete symmetries in decays of ortho-positronium in addition to the medical imaging. The gamma quanta originating from o-Ps decay interact in the plastic scintillators predominantly via the Compton effect, making the direct measurement of their energy impossible. Nevertheless, it is shown in this paper that the J-PET scanner will enable studies of the [Formula: see text] decays with angular and energy resolution equal to [Formula: see text] and [Formula: see text], respectively. An order of magnitude shorter decay time of signals from plastic scintillators with respect to the inorganic crystals results not only in better timing properties crucial for the reduction of physical and instrumental background, but also suppresses significantly the pile-ups, thus enabling compensation of the lower efficiency of the plastic scintillators by performing measurements with higher positron source activities.

Analysis of the incidence of postintubation injuries in patients intubated in the prehospital or early hospital conditions of the hospital emergency department and the intensive care unit

BACKGROUND

Intubation is still one of the best methods to secure the airway. In the case of prehospital or early hospital conditions when factors such as urgency, stress, or inaccuracy of the undertaken activities are involved, the risk of causing complications, for instance, edema or postintubation injuries, increases, especially while dealing with a difficult intubation. The risk of improper inflation of the endotracheal tube cuff also increases, which is considered in this study.

OBJECTIVE

The aim of this study was to evaluate the prevalence of postintubation complications, such as postintubation injuries or edema, in a research sample, and to examine whether such complications occur more often, for example, while using a guidewire. In this study, we also evaluated the injuries associated with the inflation of the endotracheal tube cuff.

MATERIALS AND METHODS

This study was performed on a group of 153 patients intubated in prehospital conditions. The tests were carried out in three clinical sites that received patients from prehospital care. Postintubation injuries were revealed and photographed using videolar-yngoscope, such as the C-MAC and the McGrath series 5. The endotracheal tube cuff pressure was measured using a pressure gage manual (VBM Medizintechnik GmbH). The quantitative analyses of differences between incidence of variables were assessed using χ (2) test for P<0.05. Analyses have been carried out using the Statistica software.

RESULTS

In the group of 153 patients, postintubation injuries occurred in 17% of cases. The dependency between using the guidewire and the occurrence of the hematomas and loss of mucosa was statistically significant (P<0.01). In nearly half (42%) of the patients the endotracheal tube cuff pressure was excessively inflated over 30 cm H2O, and in two cases, endotracheal tube displacement was observed on account of poor cuff inflation (<20 cm H2O).

CONCLUSION

The highest percentage of overfilled cuffs were observed in the admission room. In the other wards, it was observed in 25% of cases. Even though only six cases of poor cuff inflation were noticed, the relationship between the leakage and the clinical conditions of patients is worth examining. The results would help in taking additional measures to reduce the risk of complications.

The comparison of the technical parameters in endotracheal intubation devices: the Cmac, the Vividtrac, the McGrath Mac and the Kingvision

Currently, there are plenty of videolaryngoscopes that appear on the market. They have different specifications. Some of these features favor the fact that they are more suited for educational purposes of future operators and others can be characterized with an excellent clinical use. In this study we compared four types of videolaryngoscopes. The aim of the study was to compare the technical specifications of the above-mentioned devices for usefulness in clinical practice and correlate these parameters with the subjective evaluation of these videolaryngoscopes usage performed in practice by an experienced medical staff. All devices considered in this study participated in another multicenter clinical study on the basis of which we completed the subjective evaluation of the operators. In order to examine the technical parameters of the equipment we established the cooperation with the Department of Microelectronics at Technical University of Lodz. Mechanical and optical parameters and the endoscopic tube current were taken into consideration. The C-MAC has a camera with the widest viewing angle (the OX axis-63.1, the axis OY-47.8), which in combination with the largest diagonal size of the display enables the operator to see the details relevant to clinical practice. It has also the strongest lamp intensity of the devices mentioned in this comparison (7800 Lx). In comparison of the clinical use in almost all compared parameters the Cmac D-blade is a winner, although for clinical education purpose we consider the Vividtrac a better device.

Boussignac CPAP system for brain death confirmation with apneic test in case of acute lung injury/adult respiratory distress syndrome - series of cases

Introduction

There are some patients with severe respiratory disturbances like adult respiratory distress syndrome (ARDS) and suspicion of brain death, for whom typical performance of the apneic test is difficult to complete because of quick desaturation and rapid deterioration without effective ventilation. To avoid failure of brain death confirmation and possible loss of organ donation another approach to apneic test is needed. We present two cases of patients with clinical symptoms of brain death, with lung pathology (acute lung injury, ARDS, lung embolism and lung infection), in whom apneic tests for recognizing brain death were difficult to perform. During typical performance of apneic test involving the use of oxygen catheter for apneic oxygenation we observed severe desaturation with growing hypotension and hemodynamic destabilization. But with the use of Boussignac CPAP system all necessary tests were successfully completed, confirming the patient’s brain death, which gave us the opportunity to perform procedures for organ donation. The main reason of apneic test difficulties was severe gas exchange disturbances secondary to ARDS. Thus lack of positive end expiratory pressure during classical performance of apneic test leads to quick desaturation and rapid hemodynamic deterioration, limiting the observation period below dedicated at least 10-minute interval.

Conclusion

The Boussignac CPAP system may be an effective tool for performing transparent apneic test in case of serious respiratory disturbances, especially in the form of acute lung injury or ARDS.

Superselective renal artery embolization in the treatment of iatrogenic bleeding into the urinary tract

BACKGROUND

The aim of this study was to evaluate the efficacy of superselective renal artery embolization in patients with bleeding into the urinary system.

MATERIAL/METHODS

From 2007 to 2012, 20 patients were treated with superselective renal artery embolization for bleeding after percutaneous nephrolithotomy (PCNL), nephron-sparing surgery (NSS), including 1 patient with AVF after PCNL. During the procedure, embolization material was injected through a microcatheter to stop the bleeding. Embolization materials included a mixture of cyanoacrylate and lipiodol, embolization coils, and Spongostan. Clinical evaluation included remission of hematuria and normalization of blood morphotic elements.

RESULTS

The cause of bleeding into the urinary tract was damage to vessels (all cases): with coexisting false aneurism (8 cases); with coexisting arterio-venus fistula (1 case); and with coexisting intrarenal hematoma (3 cases). The bleeding occurred 2-5 days after PCNL and NSS, and 10 days after PCNL with AVF. The mean hematocrit level was 22%-24%. Technical success was achieved in 20 cases. Clinical success was achieved in 19 cases. One patient with hematuria after PCNL with AVF needed a second endovascular treatment to stop bleeding.

CONCLUSIONS

Superselective renal artery embolization is an effective procedure in the treatment of iatrogenic bleeding into the urinary tract after PCNL and NSS.

The doripenem serum concentrations in intensive care patients suffering from acute kidney injury, sepsis, and multi organ dysfunction syndrome undergoing continuous renal replacement therapy slow low-efficiency dialysis

Doripenem is a novel wide-spectrum antibiotic, and a derivate of carbapenems. It is an ideal antibiotic for treatment of serious nosocomial infections and severe sepsis for its exceptionally high efficiency and broad antibacterial spectrum of action. Doripenem is eliminated mainly by the kidneys. In cases of acute kidney injury, dosing of doripenem depends on creatinine clearance and requires adjustments. Doripenem is eliminated during hemodialysis because its molecular weight is 300–400 Da. The aim of this study was to establish the impact of continuous renal replacement therapy (CRRT) slow low-efficiency dialysis (SLED) on doripenem serum concentrations in a population of intensive-therapy patients with life-threatening infections and severe sepsis. Ten patients were enrolled in this observational study. Twelve blood samples were collected during the first administration of doripenem in a 1-hour continuous infusion while CRRT SLED was provided. Fluid chromatography was used for measurement of the concentration of doripenem in serum. In all collected samples, concentration of doripenem was above the minimum inhibition concentration of this antibiotic. Based on these results, we can draw the conclusion that doripenem concentration is above the minimum inhibition concentration throughout all of CRRT. The dosing pattern proposed by the manufacturer can be used in patients receiving CRRT SLED without necessary modifications.

The effect of spent bleaching earth ageing process on its physicochemical and microbial composition and its potential use as a source of fatty acids and triterpenes

This study was aimed at investigating the physicochemical and microbiological changes that took place during the ageing process of spent bleaching earth in the presence of autochthonous microorganisms. Research material included fresh spent bleaching earth (SBE0) and the same material after 3 years of storage at the constant temperature of 20 °C, without aeration and moistening (SBE3). Changes in the chemical composition of analysed waste material were observed during its ageing process point to a spontaneous bioconversion of fat substance towards formation and/or release of free saturated fatty acids C16:0 and C18:0 (14.3 g 100 g(-1) D.M.), triterpenes (8.48 g 100 g(-1) D.M.), cholesterol (3.29 g 100 g(-1) D.M.), small quantities of carbohydrates and esters (0.80 g 100 g(-1) D.M.). This process was accompanied by other changes in physicochemical parameters of the waste material, such as colour, odour and viscosity, decrease in fat content from 28.27 to 24.6 % and that of soluble forms of metals (Mo, Cu, Fe, Zn, Ni, Cr and Mn), ranging from 25 to 75 %, and an increase in pH, from 3.85 to 4.2. At the same time, changes in the microbial consortium were observed.

A comparison of conventional tube and EndoFlex tube for tracheal intubation in patients with a cervical spine immobilisation

BACKGROUND

The EndoFlex is a new type of tracheal tube with an adjustable distal tip that can be bent without the use of a stylet. The aim of this study was to compare a standard endotracheal tube with the EndoFlex tracheal tube for intubation in patients with simulated cervical spine injury.

METHODS

A group of 60 patients without any kind of the cervical spine injury, classified as the ASA physiological scale I or II and qualified for elective surgery procedures were intubated with the use of classical Macintosh laryngoscope, and either a standard endotracheal tube with the intubation stylet in it or EndoFlex tube without stylet. The subjects were randomized into two subgroups. All patients have had the cervical collar placed on their neck for the simulation of intubation procedure in case of the spinal injury.

RESULTS

The intubation procedure was performed by 16 anesthetists with different experience (5-19 yrs). Time of intubation with the use of EndoFlex tube was similar to that with a the use of standard endotracheal tube and intubation stylet: Me (median) 19.5 s [IQR (interquatile range) 18-50] vs. Me 20 s [IQR 17-60] respectively (p = 0.9705). No significant additional maneuvers were necessary during intubation with the use of EndoFlex tube in comparison with standard endotracheal tube (70% vs. 56.6%) (p = 0.4220). Subjective assessment of the usability of both tubes revealed that more anesthesiologists found intubations with the use of EndoFlex more demanding than intubation with conventional tracheal tube and intubation stylet. The assessment of usability: very easy 3.3% vs. 20%, easy 83.4% vs. 56.7%, difficult 10% vs. 20% and very difficult 3.3% vs. 3.3% for standard endotracheal tube with stylet and EndoFlex, respectively.

CONCLUSION

In conclusion we asses, that the EndoFlex tube does not improve intubation success rate, in fact it requires more maneuvers facilitating intubation and was found to be more difficult to use.

Changes in the anaerobic threshold in an annual cycle of sport training of young soccer players

The aim of the study was to assess changes in the anaerobic threshold of young soccer players in an annual training cycle. A group of highly trained 15-18 year old players of KKS Lech Poznań were tested. The tests included an annual training macrocycle, and its individual stages resulted from the time structure of the sports training. In order to assess the level of exercise capacities of the players, a field exercise test of increasing intensity was carried out on a soccer pitch. The test made it possible to determine the 4 millimolar lactate threshold (T LA 4 mmol · l^-1) on the basis of the lactate concentration in blood [LA], to establish the threshold running speed and the threshold heart rate [HR]. The threshold running speed at the level of the 4 millimolar lactate threshold was established using the two-point form of the equation of a straight line. The obtained indicators of the threshold running speed allowed for precise establishment of effort intensity used in individual training in developing aerobic endurance. In order to test the significance of differences in mean values between four dates of tests, a non-parametric Friedman ANOVA test was used. The significance of differences between consecutive dates of tests was determined using a post-hoc Friedman ANOVA test. The tests showed significant differences in values of selected indicators determined at the anaerobic threshold in various stages of an annual training cycle of young soccer players. The most beneficial changes in terms of the threshold running speed were noted on the fourth date of tests, when the participants had the highest values of 4.01 m · s^-1 for older juniors, and 3.80 m · s^-1 for younger juniors. This may be indicative of effective application of an individualized programme of training loads and of good preparation of teams for competition in terms of players’ aerobic endurance.

Effects of construction changes in the teeth of a gear transmission on acoustic properties

This paper presents results of experimental research on the acoustic properties of gear wheels with high-profile teeth with differentiated tooth height. Those results showed that gear transmissions with high-profile teeth have the best acoustic properties, with the value of the transverse contact ratio εα ≈ 2.0. They also showed that a reduction in tooth height, and thereby in contact ratio, increased the sound pressure level.

The screening of microorganisms capable of methyl tert-butyl ether (MTBE) biodegradation

As a result of examinations carried out, 16 strains of microorganisms able to grow on mineral media with methyl tert-butyl ether as the sole source of carbon and energy were isolated. Bacteria prevailed among the isolated microorganisms. The growth of microorganisms under laboratory conditions was long and accompanied by low biomass increase. Under the conditions of the experiment, the isolated microorganisms did not show any quantitatively measurable biodegradability of methyl tert-butyl ether (MTBE) under aerobic conditions. This requires far-reaching caution with respect to trading in MTBE-modified petrols in order to protect the natural environment in Poland against contamination with that hard-to-biodegrade substance.

Prediction of outcome of fetal congenital heart disease using a cardiovascular profile score

OBJECTIVES

Congestive heart failure in fetuses with congenital heart defects (CHD) is associated with high perinatal mortality. The clinical condition can be characterized by five ultrasound markers that comprise the 10-point cardiovascular profile (CVP) score. Our aim was to assess the value of the CVP score in evaluating the condition and in maintaining surveillance of fetuses with CHD.

METHODS

We evaluated retrospectively 131 singleton pregnancies with a diagnosis of fetal CHD, which had been assessed by serial echocardiographic examinations, during which the CVP score was obtained. Fetal and neonatal outcomes, including perinatal mortality and Apgar scores, were assessed.

RESULTS

Fetuses with a final CVP score <or= 7 were statistically significantly more likely to suffer mortality than were fetuses with a final CVP score >or= 8 (87.5% vs. 15.2% mortality; P < 0.0001, chi square = 24.5). Significance was maintained after controlling for birth weight, lag time between the final examination and delivery and the dichotomized 5-min Apgar score (odds ratio, 22.3; P = 0.024). For low Apgar score and mortality, the CVP score had low sensitivity (0.25 and 0.27, respectively) but high specificity (0.98 and 0.99, respectively). The presence of hydrops and severe cardiomegaly were statistically significantly associated with mortality (P < 0.05).

CONCLUSIONS

Fetuses with CHD and a CVP score below 8 are at risk of perinatal death. The CVP score may be used to assess the severity of fetal CHD and to plan perinatal management.