Are high-sensitivity troponins always reliable? Donor-recipient troponin transfusion in liver transplantation.

Blood troponins are used to diagnose perioperative myocardial injury and infarction. During liver transplantation, a passive donor-recipient troponin transfer with the graft may result in an increase of troponins in the transplant recipient questioning the diagnosis of myocardial injury. We present a case of liver transplantation with sudden elevation of recipient's serum troponin levels immediately after graft reperfusion and its subsequent normalization in which myocardial damage and other non-ischaemic potential causes were ruled out. Patient consent for publication was obtained prior to submission of the manuscript.

Degradation and detoxification of 4-nitrophenol by advanced oxidation technologies and bench-scale constructed wetlands.

The degradation and detoxification towards the duckweed Lemna minor of 4-nitrophenol (4NP) was studied by means of bench-scale constructed wetlands (CWs), TiO(2)-photocatalysis and Fenton + photoFenton reactions. The main goal of this work was to compare the three treatment techniques to evaluate their possible combination for the efficient, low cost treatment of 4NP effluents. In CWs, adsorption on the substrate of 4NP was found to achieve 34-45%. Low concentrations (up to 100 ppm) of 4NP were successfully treated by CWs in 8-12 h. The microbial degradation of 4NP started after a lag phase which was longer with higher initial concentrations of the pollutant. The greatest degradation rate was found to occur at initial concentrations of 4NP between 60 and 90 ppm. Solar TiO(2)-photocatalysis was faster than the CWs. The greatest removals in terms of mass of 4NP removed after 6 h of irradiation were found to occur at 4NP concentrations of about 200 ppm. Fenton reaction provided complete 4NP degradation up to 500 ppm in only 30 min but TOC was removed by only about 40%. The resulting toxicities were below 20% for initial 4NP concentrations below 300 ppm. It was the Fenton + photoFenton combination (180 min in total) that provided TOC reductions up to 80% and negative L. minor growth inhibition for almost all the 4NP concentrations tested. The combination of solar TiO(2)-photocatalysis (6 h) with CWs (16 h) was able to completely treat and detoxify 4NP effluents with concentrations as high as 200 ppm of the organic.

Evaluation of Plasma Disappearance Rate Indocyanine Green Clearance as a Predictor of Liver Graft Rejection in Donor Brain Death.

INTRODUCTION: There currently exist no quantitative methods to assess graft viability before the donor procurement procedure. In Europe, around 20% of liver grafts evaluated "in situ" by an experienced surgeon are discarded. The aim of this study is to evaluate the use of the plasma disappearance rate indocyanine green (PDR-ICG) clearance in predicting liver graft rejection to avoid this 20% of futile surgeries. OBJECTIVES: To evaluate PDR-ICG as a predictor of liver graft rejection in death brain donors compared with the gold standard evaluation by an experienced surgeon. MATERIAL AND METHODS: Prospective observational single center study. From March 2017 to July 2019, 29 donors were included in the study, 17 were men and 12 women with a median age of 68 years ± 16.9 years. Donors had an intensive care unit stay of 2 days ± 4 days. PDR-ICG was measured with PICCO2 monitor. Indocyanine green clearance dose was 0.25 mg/kg injected intravenously in the operating room just before donor procurement procedure is initiated. The surgeon was unaware of the PDR-ICG measure until the decision of graft acceptance was taken. Data regarding the donors and biopsy results were included in a prospective database. RESULTS: PDR-ICG measure could be obtained in 10 minutes in all of the cases included. The median PDR-ICG obtained was 18%/min (range, 2.4-31%/min). Graft rejection took place in 15 out of the 29 donors. PDR-ICG value was less than 10%/min in 6 of these rejected grafts and less than 15%/min in 10 donors. All donor grafts with PDR-ICG <15% were discarded. The graft had been discarded in 5 donors with a PDR-ICG >15%. CONCLUSIONS: In our study a plasma disappearance rate <10 would have identified the grafts that would be rejected, thus avoiding the displacement work and expense of the surgical team. These results should be confirmed in a multicentric study.

Donor Risk Index Has an Impact in Intraoperative Measure of Hepatic Artery Flow and in Clearance of Indocyanine Green: An Observational Cohort Study.

BACKGROUND: The increase in indications for liver transplantation has led to acceptance of donors with expanded criteria. The donor risk index (DRI) was validated with the aim of being a predictive model of graft survival based on donor characteristics. Intraoperative arterial hepatic flow and indocyanine green clearance (plasma clearance rate of indocyanine green [ICG-PDR]) are easily measurable variables in the intraoperative period that may be influenced by graft quality. Our aim was to analyze the influence of DRI on intraoperative liver hemodynamic alterations and on intraoperative dynamic liver function testing (ICG-PDR). METHODS: This investigation was an observational study of a single-center cohort (n = 228) with prospective data collection and retrospective data analysis. Measurement of intraoperative flow was made with a VeriQ flowmeter based on measurement of transit time (MFTT). The ICG-PDR was obtained from all patients with a LiMON monitor (Pulsion Medical Systems AG, Munich, Germany). DRI was calculated using a previously validated formula. Normally distributed variables were compared using Student's t test. Otherwise, the Mann-Whitney U test or Kruskal-Wallis test was applied, depending on whether there were 2 or more comparable groups. The qualitative variables and risk measurements were analyzed using the chi-square test. P < .05 was considered statistically significant. RESULTS: DRI score (mean ± SD) was 1.58 ± 0.31. The group with DRI >1.7 (poor quality) had an intraoperative arterial flow of 234.2 ± 121.35 mL/min compared with the group having DRI < 1.7 (high quality), with an intraoperative arterial flow of 287.24 ± 156.84 mL/min (P = .02). The group with DRI >1.70 had an ICG-PDR of 14.75 ± 6.52%/min at 60 minutes after reperfusion compared to the group with DRI <1.70, with an ICG-PDR of 16.68 ± 6.47%/min at 60 minutes after reperfusion (P = .09). CONCLUSION: Poor quality grafts have greater susceptibility to ischemia-reperfusion damage. Decreased intraoperative hepatic arterial flow may represent an increase in intrahepatic resistance early in the intraoperative period.

Combining TiO2-photocatalysis and wetland reactors for the efficient treatment of pesticides.

In the present work the photocatalytic and biological degradation of two commercial mixtures of pesticides (Folimat and Ronstar) and two fungicides (pyrimethanil and triadimenol) has been studied. The evolution of some components of these commercial products (dicofol, tetradifon and oxadiazon) and that of the two fungicides has been monitored by means of HPLC, GC-MS, TOC and toxicity (Lemna minor toxicity test) measurements. The photocatalytic method was able to degrade dicofol, tetradifon, pyrimethanil, triadimenol and the components of Ronstar with the exception of oxadiazon. In addition to this, the photocatalytic method eliminated pyrimethanil toxicity and reduced that of triadimenol by a 90%, Ronstar by a 78% and Folimat by an 87%. Nevertheless, the wetland reactors alone could reduce the toxicity of only the former. Finally, the proper dosage of the water containing the pesticides to a photocatalytic reactor followed by a wetland reactor resulted to be the most successful strategy for the detoxification of the studied compounds and their mixtures.

Photocatalytic degradation of phenol and phenolic compounds Part I. Adsorption and FTIR study.

With the goal of predicting the photocatalytic behaviour of different phenolic compounds (catechol, resorcinol, phenol, m-cresol and o-cresol), their adsorption and interaction types with the TiO(2) Degussa P-25 surface were studied. Langmuir and Freundlich isotherms were applied in the adsorption studies. The obtained results indicated that catechol adsorption is much higher than those of the other phenolics and its interaction occurs preferentially through the formation of a catecholate monodentate. Resorcinol and the cresols interact by means of hydrogen bonds through the hydroxyl group, and their adsorption is much lower than that of catechol. Finally, phenol showed an intermediate behaviour, with a Langmuir adsorption constant, K(L), much lower than that of catechol, but a similar interaction. The interaction of the selected molecules with the catalyst surface was evaluated by means of FTIR experiments, which allowed us to determine the probability of OH radical attack to the aromatic ring.

Autonomic neuropathy in end-stage cirrhotic patients and evolution after liver transplantation.

Autonomic neuropathy (AN), which is frequently observed in cirrhosis patients, has been associated with a higher mortality. We have prospectively evaluated the prevalence of AN, its relationship with the degree of liver dysfunction and circulatory disturbances, and the evolution of AN after liver transplantation (LT) in 62 end-stage liver cirrhosis patients. AN was evaluated by seven cardiovascular tests assessing sympathetic or parasympathetic function before and 6 months after LT. Patients were classified as showing absent (A), early (E), or definite dysfunction (D). AN appeared in 67.7% of cases (E: 24.2%, D: 43.5%) without relation to liver disease etiology. Parasympathetic dysfunction was more prevalent than sympathetic dysfunction (59.7% vs. 20.9%). AN was significantly related to Child-Pugh score. Hyperdynamic circulation was more marked in the D than the A group as shown by a greater cardiac output (CO)(9 vs. 7.3 L/min) and a lower peripheral resistance (SVR)(666 vs. 866 dyn.s.cm(-5)). Moreover, AN scores significantly correlated with CO and SVR. Overall the prevalence of AN decreased 6 months after LT (67.7% vs 48%) due to a significant reduction in definite AN (43.5 vs. 14.8%; P<.05). AN improved in 70% of cases after LT. Sympathetic dysfunction remained in only one patient. We conclude that AN is frequent in liver transplant candidates; its severity is associated with the degree of liver failure. Systemic circulatory disturbances seem to correlate with the severity of AN. AN is clearly improved by LT. The evaluation of AN may contribute to a better selection of LT recipients.

Autonomic neuropathy is associated with hemodynamic instability during human liver transplantation.

INTRODUCTION: End-stage liver disease is frequently associated with autonomic neuropathy (AN). The hemodynamic changes during liver transplantation (LT) require an adequate autonomic response to maintain cardiovascular stability. PATIENTS AND METHODS: Forty-one patients undergoing LT were evaluated for the influence of AN on the evolution after LT. AN was previously evaluated by seven cardiovascular tests assessing sympathetic (Sy) or parasympathetic (P) function. Patients were classified as absent (A), early (E), or definite dysfunction (D). A hemodynamic study was performed before and after vascular clampings. The analysis included the duration of LT, transfusion requirements, intra-operative artenal hypotensive episodes, incidence of postreperfusion syndrome (PRS), cardiac arrhythmias and vasoactive drug requirements. RESULTS: The hyperdynamic circulation worsened during surgery in D patients, as shown by a significantly increased cardiac output and a significantly decreased systemic vascular resistance. The incidence of PRS was greater in the AN group. Arterial hypotension during the neohepatic period was more frequent among patients with AN, more frequently requiring vasoconstrictor and inotropic therapy. CONCLUSIONS: AN is associated with hemodynamic impairment and with increased vasoactive drug requirements during liver transplantation, probably associated with impaired reflex vasoconstrictor responses to surgical manipulations and changes of blood volume. AN may be associated with a greater surgical risk during LT. Preoperative evaluation of AN may select a high-risk population of LT recipients.

Cardiac output by femoral arterial thermodilution-calibrated pulse contour analysis during liver transplantation: comparison with pulmonary artery thermodilution.

PURPOSE: The continuous monitoring of the cardiac output during liver transplantation (LT) is an essential part of the intraoperative management of the patient's hemodynamics. To verify the accuracy of a new method based on femoral artery thermodilution-calibrated pulse contour analysis (PCCO) during LT, we compared the technique with the results of an intermittent pulmonary artery thermodilution method (ICO). METHOD: A prospective study included 314 paired cardiac output measurements at 10 sampling times in 35 patients undergoing LT. After initial calibration of the pulse contour analysis, no further recalibrations were performed. Bland and Altman's statistical method, one-way ANOVA, and one sample t tests were used for the analysis of the data. A P<.05 was considered significant. RESULTS: There was a small bias 0.18 L x min(-1) (6.29% from the ICO) for the whole sample of paired measurements, associated with 95% limits of agreement of +/-4.72 (68.89%) L x min(-1). The additional analysis showed comparable biases and limits of agreement for any single time in the study period. The difference PCCO-ICO showed a negative sign for ICO >10 L x min(-1) (P<.001) and a positive sign for ICO <5 L x min(-1) (P<.001). It was greater during infusion of a vasoactive drug (P<.001). CONCLUSION: The pulse contour analysis was found to be an unsatisfactory substitute for intermittent thermodilution measurement of cardiac output during the LT.

Highly concentrated phenolic wastewater treatment by the photo-Fenton reaction, mechanism study by FTIR-ATR.

Phenol degradation by Photo-Fenton reaction has been studied in highly concentrated wastewaters and most intermediate species have been identified by Fourier Transform IR-Spectroscopy with ATR device. During the photodegradation of highly concentrated phenol solutions, the formation of dissolved and precipitate tannin has been observed. The possibility of a Fe3+-Pyrogallol complex formation, previous to the tannin formation, has been proposed too. The complex formation involving Fe3+ ions could be related to the observed Photo-Fenton activity decrease. Tannin formation inhibits the complete mineralization of phenol because *OH radicals attack will produce further condensation steps and the polymer size increase. This fact limits the applicability of the process for highly concentrated phenolic wastes mineralization. However, the tannin precipitation allows its separation from the solution by conventional filtration, and reduction of the corresponding dissolved organic carbon. These observations have been proved from the identification of primary degradation products, catechol and hydroquinone. Catechol is considered to be the first step for the formation of tannins. Degradation process for phenol, catechol and hydroquinone have been monitored by total organic carbon (TOC) measurements along the reaction time span. From these results, a global mechanism for the Photo-Fenton degradation of phenol is proposed.

The photocatalytic disinfection of urban waste waters.

In this paper we present the results of the photocatalytic disinfection of urban waste water. Two microbial groups, total coliforms and Streptococcus faecalis, have been used as indexes to test disinfection efficiencies. Different experimental parameters have been checked, such as the effect of TiO2, solar or UV-lamp light and pH. Disinfection of water samples has been achieved employing both UV-lamp and solar light in agreement with data shown by other authors. The higher disinfection rates obtained employing an UV-lamp may be explained by the stronger incident light intensity. Nevertheless no consistent differences have been found between TiO2-photocatalysis and direct solar or UV-lamp light irradiation at natural sample pH (7.8). At pH 5 the presence of TiO2 increases the relative inactivation rate compared with the absence of the catalyst. After the photocatalytic bacterial inactivation, the later bacterial reappearance was checked for total coliforms at natural pH and pH 5, with and without TiO2. Two h after the photocatalytic treatment, CFU increment was almost nill. But 24 and 48 h later an important bacterial CFU increment was observed. This CFU increment is slower after irradiation with TiO2 at pH 5 in non-air-purged samples.

Photocatalytic degradation of formaldehyde containing wastewater from veterinarian laboratories.

The photocatalytic destruction of methanol, formaline (mixture of formaldehyde, methanol and water) and formaline wastes from the preservation of vertinarian physiologic samples has been attempted by two different processes, at high concentrations of reagents and by dossification of reagents, varying pH in both. Experiment evolution has been monitored by measuring the organic matter such as TOC and formaldehyde concentrations [H2CO]. Also, methanol and methanol-formaldehyde interactions with the TiO2 surface have been analysed by FTIR spectroscopy. Results indicate that at high concentrations the catalyst surfacial alterations given by methoxy, formates or carbonates, according to the pH of the sample can profoundly affect catalyst behaviour. It has been established that reagent dossification is advantageous for enhancing photonic efficiency as it minimizes the adsorbate presence that hampers the photocatalytic process.

Highly concentrated phenolic wastewater treatment by heterogeneous and homogeneous photocatalysis: mechanism study by FTIR-ATR.

The degradation of high phenol concentrations (1 g/L) in water solutions by TiO2 photocatalysis and the photo-Fenton reaction has been studied. From the obtained data it may be suggested that degradation of phenol by TiO2-UV takes place onto the catalyst surface by means of peroxo-compounds formation. At low phenol concentrations other mechanism, the insertion of OH. radicals, may be favored. On the other hand, highly concentrated phenol aqueous solutions treatment by the photo-Fenton reaction gives rise to the formation of polyphenolic polymers. These seem to reduce the process rate. Degradation intermediates have been identified by HPLC and FTIR. The FTIR study of the catalyst surface has shown infrared bands attributable to different chemisorbed peroxo-compounds, formates, ortho-formates and carboxylates that can inactivate the catalyst.

[Effect of an intravenous nitroglycerin bolus on the hemodynamic impact of laryngoscopy and intubation]. / Efecto de la nitroglicerina intravenosa en bolo sobre la repercusión hemodinámica de la laringoscopia e intubación.

The aim of this study was to evaluate the effectiveness of intravenous administration of a single dose of nitroglycerin in lessening the hemodynamic effects induced during laryngoscopy and tracheal intubation. In an initial subset of 8 patients we verified that the hemodynamic changes after an intravenous dose of 2, 5, or 10 micrograms/kg of nitroglycerin were comparable. The study included 30 patients with a good clinical condition who were anesthetized with fentanyl, thiopental sodium and succinylcholine. They were allocated into two groups of 15 patients according to the intravenous administration or not of 2 micrograms/kg of nitroglycerin after induction of anesthesia. Increase in systolic blood pressure (SBP) and double product (SBP x heart rate) during laryngoscopy and 15, 30, and 45 seconds thereafter was significantly lower in nitroglycerin treated patients than in controls. Increase in diastolic blood pressure was also lower in nitroglycerin treated patients but this difference was only present during laryngoscopy. There were no significant heart rate differences among the two groups of patients. It is concluded that a single intravenous dose of 2 micrograms/kg of nitroglycerin was able to lessen the increase in blood pressure induced by laryngoscopy and tracheal intubation without deleterious effects.

[Massive transfusion: methods and complications]. / Transfusión masiva: métodos y complicaciones.

Massive blood transfusion is a therapeutic procedure increasingly common in anesthesiologic practice. In the present study we reviewed the literature on cellular changes and biochemical abnormalities developing in the blood components during storage. We also reviewed the different methods for infusion and the flow achieved depending on the type of intravenous catheter, infusion system, pressure methods, characteristics of the fluid, and type of filter. We also assessed the pathophysiology of the complications of massive blood transfusion: abnormalities of coagulation, metabolism, oxygen transportation, pulmonary function, hemodynamics and erythrocyte shape, plasma proteins denaturalization, toxicity of plastic products and hypoglycemia.

[Intracavitary electrocardiography. A useful method for checking the correct localization of central venous catheters]. / Electrocardiografía intracavitaria. Un método útil para la comprobación de la correcta colocación de los catéteres venosos centrales.

A placement technique for central venous catheters (CVC) using the intracavitary electrocardiography (ICECG) as well as three different connection systems of the CVC to the electrocardiographic monitor are described. The aim of the present study was to evaluate the correct placement of the CVC by this technique with posterior radiologic confirmation being carried out. The study was undertaken in 30 patients connecting a CVC to a negative electrode of the standard lead II and the positive to the left leg. The CVC was advanced and the changes in the morphology of the "P" wave as it passed along the superior vena cava (SVC) to the right auricle (RA) were observed. In 28 of the 30 patients (93.3%) a biphasic "P" wave (right auricle) was achieved with the CVC being thereafter withdrawn until the SVC (this location was radiologically confirmed posteriorly). In 2 patients (6.6%) a biphasic "P" wave was not obtained and an abnormal position of the CVC was radiologically demonstrated at surgery (one in the ipsilateral subclavian vein and the other had a ring within the right subclavian vein impeding progression). The mean time used in the performance of this technique was 220 +/- 40 s. It is concluded that intracavitary electrocardiography is a simple, easy to learn and perform technique which does not delay surgical procedure and it is a reliable method for placing the end of the CVC.

[Internal jugular vein catheterization performed by resident and staff physicians]. / Cateterización de la vena yugular interna realizada por médicos residentes y adjuntos.

OBJECTIVES: To analyse complications in the catheterization of the internal jugular vein using the Boulanger technique and to establish a rating of difficulty and risk when the procedure is carried out by physicians in training. MATERIAL AND METHODS: This was a prospective study of 296 internal jugular vein (IJV) catheterizations by the Boulanger technique carried out by physicians in training (group R2 and group R3-4) or by departmental staff physicians (group staff). Time taken for venous catheterization, rate of success and complications were recorded for each physician performing the procedure. RESULTS: The complication most often observed (11.4%) was puncture of the carotid artery (14.3% group R2, 10% group R3-4 and 8.2% staff), followed by arrhythmia upon insertion of the metal guide (1.6%). There were no instances of pneumothorax or hemothorax, nor any other of the early complications considered infrequent. Success ranged from 68.8% for group R2 to 85.7% for staff. Mean time used in group R2 was 238.7 seconds, while for staff it was 118.3 seconds. CONCLUSION: We suggest that the Boulanger technique for catheterization of the internal jugular vein is a good one and is not particularly hazardous when performed by resident physicians in training.

[Effects of postoperative pain on lung volume in patients undergoing aortic surgery]. / Repercusión del dolor postoperatorio sobre los volúmenes pulmonares en pacientes sometidos a cirugía aórtica.

To evaluate the potential advantages of the administration of extradural morphine to control postoperative pain and its effects on respiratory function, 39 patients were randomly assigned to one of two groups before aortic surgery. The first group (20 patients) received intravenous analgesia as required (control group). The second group (19 patients) received extradural morphine in a programmed fashion. During the immediate postoperative period the following parameters were measured in both groups: respiratory rate, vital capacity, peak expiratory volume in the first second, PaO2, PaCO2, arterial pH, heart rate, and systolic and diastolic blood pressure. In the group treated with morphine the postoperative increase in heart and respiratory rate was significantly smaller than in the control group (p less than 0.01). Postoperative forced pulmonary volumes were higher in the morphine group (p less than 0.01). However, there were no differences in time of hospitalization between both groups. There were more complications in the control group, but the difference did not reach statistical significance.

[Pulmonary atelectasis in bent lateral decubital position (nephrectomy). Apropos of a case]. / Atelectasia pulmonar en la posición de decúbito lateral flexionado (nefrectomía). A propósito de un caso.

Here we have the case of a right nephrectomy ureterectomy for urothelial neoformations in the upper urinary apparatus, in the position of a left flexed lateral decubitus (nephrectomy) practised to a patient, in which a small right pleural aperture was unnoticed until the end of the operation when the closing was being carried out. In the immediate postoperative, the patient developed hypoxia and hypercapnia, as well as an atelectasis of the lower lobus in the left lung, that appeared in the radiological test. We comment now the causes that could have originated this picture, such as overweight, the position of the patient during the operation, its length and the pleural aperture throughout the surgical act, focusing the study in this latter point.

Cardiac output monitoring with pulmonary versus transpulmonary thermodilution during liver transplantation: interchangeable methods?

BACKGROUND: Liver transplantation (LT) implies hemodynamic instability, making invasive monitoring of cardiac output (CO) mandatory. Intermittent thermodilution with pulmonary artery catheter (PAC) remains the clinical gold standard to measure CO. The agreement between PAC and new monitoring methods in LT needs to be further investigated. Our aim is to clarify whether cardiac index (CI) measurements with transpulmonary intermittent thermodilution, and continuous pulmonary thermodilution methods agree sufficiently with those performed intermittently with PAC to be considered interchangeable during LT. METHODS: We studied prospectively hemodynamic parameters of 72 consecutive patients undergoing LT. Each CI was obtained simultaneously with three different techniques: intermittent (PACi) and continuous (CCI) pulmonary artery thermodilution with PAC, and intermittent transpulmonary thermodilution (TPTD) with PiCCO2 in 8 time points of the procedure, obtaining 1350 paired measurements. Exclusion criteria was retransplantation. The statistical Bland Altman method for repeated measures was used to assess agreement, and polar plot methodology to evaluate trending ability. RESULTS: Analysis of agreement between PACi and TPTD measurements (N.=474 paired measurements) showed a bias of -0.42 L/min/m2, 95% limits of agreement (95%LoA) of ±1.5 L/min/m2 and percentage error of 45%. PACi-CCI comparisons (N.=431) showed bias of -0.02 L/min/m2, 95%LoA of ±1.96 L/min/m2, and percentage error of 64%. These results demonstrated questionable clinical agreement between PACi and TPTD, and no agreement between PACi and CCI. TPTD and CCI showed poor CO trending ability. CONCLUSION: Continuous pulmonary thermodilution with PAC is not an alternative monitoring method of CO. Transpulmonary thermodilution CO monitoring with PiCCO2 shows too questionable agreement with the clinical gold standard (PACi) being in the limit of acceptance to be considered interchangeable during liver transplantation.