Changes of the nociceptive flexion reflex threshold in patients undergoing cardiac surgery-a prospective clinical pilot study.

Opioid dosage for general anaesthesia and sedation relies on surrogate parameters such as heartrate and blood pressure. This implies the risk of both under- and overdosing. A promising tool to provide target-oriented opioid dosing is measuring the nociceptive flexion reflex threshold (NFRT). The aim of this study was to investigate the individual trajectories and to determine this methods' clinical practicability in the perioperative setting of cardiac surgery. NFRT was measured preoperatively (twice as baseline), immediately after surgery and later in the general ward (primary outcomes). No intraoperative measurements were performed since neuromuscular blockade hinders NFRT assessment. Administered analgesics and pain scores were also recorded (secondary outcomes). Data were collected from August 2019 to March 2020. 264 patients scheduled for cardiac surgery were screened for eligibility. 55 patients were included, 30 rendered datasets for analysis. Thresholds after conclusion of surgery [TICU: median (IQR), 31.1 mA (21.5-50.0 mA)] were significantly higher than preoperatively [Tpre: 9.2 mA (5.4-13.4 mA); P < 0.001]. In 11 patients (36.7%), no immediate postoperative reflex response was elicited. Later, all reflexes returned, but thresholds remained significantly higher than preoperatively [Tpost: 11.9 mA (9.2-16.6 mA); P = 0.043]. NFRT values after surgery were higher compared to baseline measurements. Subsequently they decreased but did not reach their baseline levels. There was no corresponding dose-dependency, suggesting multimodal effects on the nociceptive system. Unless measurements are not prevented by technical issues NFRT-assessment appears to be a future tool to target analgesics in patients not able to self-report pain. Trial registration Study registration: DRKS00021617. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00021617 (registered retrospectively).

Pediatric supraglottic airway devices in clinical practice: A prospective observational study.

BACKGROUND: Supraglottic airway devices (SGA) are commonly used in pediatric anesthesia and serve as primary or back-up devices for difficult airway management. Most SGA are marketed without proper clinical evaluation. The purpose of this study was to evaluate the performance of the pediatric LMA Supreme™, Air-Q® and Ambu® Aura-i™. METHODS: This prospective observational study was performed at Bern University Hospital, Switzerland. With ethics committee approval and a waiver for written informed consent 240 children undergoing elective surgery with an ASA class I-III and a weight of 5-30 kg were included. Three different pediatric supraglottic airway devices were assessed: The LMA Supreme™, Air-Q® and Ambu® Aura-i™. Primary outcome parameter was airway leak pressure. Secondary outcome parameters included first attempt and overall success rate, insertion time, fiberoptic view through the SGA, and adverse events. The primary hypothesis was that the mean airway leak pressure of each tested SGA was 20 cmH2O ± 10%. RESULTS: None of the SGA showed a mean airway leak pressure of 20 cmH2O ± 10%, but mean airway leak pressures differed significantly between devices [LMA Supreme™ 18.0 (3.4) cmH2O, Air-Q® 15.9 (3.2) cmH2O, Ambu® Aura-i™ 17.3 (3.7) cmH2O, p < 0.001]. First attempt success rates (LMA Supreme™ 100%, Air-Q® 90%, Ambu® Aura-i™ 91%, p = 0.02) and overall success rates (LMA Supreme™ 100%, Air-Q® 91%, Ambu® Aura-i™ 95%, p = 0.02) also differed significantly. Insertion times ranged from 20 (7) seconds (Air-Q®) to 24 (6) seconds (LMA Supreme™,

Differentiation between Staphylococcus aureus and coagulase-negative Staphylococcus species by real-time PCR including detection of methicillin resistants in comparison to conventional microbiology testing.

BACKGROUND: Staphylococcus aureus has long been recognized as a major pathogen. Methicillin-resistant strains of S. aureus (MRSA) and methicillin-resistant strains of S. epidermidis (MRSE) are among the most prevalent multiresistant pathogens worldwide, frequently causing nosocomial and community-acquired infections. METHODS: In the present pilot study, we tested a polymerase chain reaction (PCR) method to quickly differentiate Staphylococci and identify the mecA gene in a clinical setting. RESULTS: Compared to the conventional microbiology testing the real-time PCR assay had a higher detection rate for both S. aureus and coagulase-negative Staphylococci (CoNS; 55 vs. 32 for S. aureus and 63 vs. 24 for CoNS). Hands-on time preparing DNA, carrying out the PCR, and evaluating results was less than 5 h. CONCLUSIONS: The assay is largely automated, easy to adapt, and has been shown to be rapid and reliable. Fast detection and differentiation of S. aureus, CoNS, and the mecA gene by means of this real-time PCR protocol may help expedite therapeutic decision-making and enable earlier adequate antibiotic treatment.

8p23 beta-defensin copy number determination by single-locus pseudogene-based paralog ratio tests risk bias due to low-frequency sequence variations.

BACKGROUND: The copy number variation (CNV) in beta-defensin genes (DEFB) on human chromosome 8p23 has been proposed to contribute to the phenotypic differences in inflammatory diseases. However, determination of exact DEFB CN is a major challenge in association studies. Quantitative real-time PCR (qPCR), paralog ratio tests (PRT) and multiplex ligation-dependent probe amplification (MLPA) have been extensively used to determine DEFB CN in different laboratories, but inter-method inconsistencies were observed frequently. In this study we asked which one is superior among the three methods for DEFB CN determination. RESULTS: We developed a clustering approach for MLPA and PRT to statistically correlate data from a single experiment. Then we compared qPCR, a newly designed PRT and MLPA for DEFB CN determination in 285 DNA samples. We found MLPA had the best convergence and clustering results of the raw data and the highest call rate. In addition, the concordance rates between MLPA or PRT and qPCR (32.12% and 37.99%, respectively) were unacceptably low with underestimated CN by qPCR. Concordance rate between MLPA and PRT (90.52%) was high but PRT systematically underestimated CN by one in a subset of samples. In these samples a sequence variant which caused complete PCR dropout of the respective DEFB cluster copies was found in one primer binding site of one of the targeted paralogous pseudogenes. CONCLUSION: MLPA is superior to PRT and even more to qPCR for DEFB CN determination. Although the applied PRT provides in most cases reliable results, such a test is particularly sensitive to low-frequency sequence variations preferably accumulating in loci like pseudogenes which are most likely not under selective pressure. In the light of the superior performance of multiplex assays, the drawbacks of such single PRTs could be overcome by combining more test markers.

Neutrophil extracellular trap formation during surgical procedures: a pilot study.

Neutrophils can release neutrophil extracellular traps (NETs) containing DNA fibres and antimicrobial peptides to immobilize invading pathogens. NET formation (NETosis) plays a vital role in inflammation and immune responses. In this study we investigated the impact of surgical trauma on NETosis of neutrophils. Nine patients undergoing "Transcatheter/percutaneous aortic valve implantation" (TAVI/PAVI, mild surgical trauma), and ten undergoing "Aortocoronary bypass" (ACB, severe surgical trauma) were included in our pilot study. Peripheral blood was collected before, end of, and after surgery (24 h and 48 h). Neutrophilic granulocytes were isolated and stimulated in vitro with Phorbol-12-myristate-13-acetate (PMA). NETosis rate was examined by microscopy. In addition, HLA-DR surface expression on circulating monocytes was analysed by flow-cytometry as a prognostic marker of the immune status. Both surgical procedures led to significant down regulation of monocytic HLA-DR surface expression, albeit more pronounced in ACB patients, and there was a similar trend in NETosis regulation over the surgical 24H course. Upon PMA stimulation, no significant difference in NETosis was observed over time in TAVI/PAVI group; however, a decreasing NETosis trend with a significant drop upon ACB surgery was evident. The reduced PMA-induced NETosis in ACB group suggests that the inducibility of neutrophils to form NETs following severe surgical trauma may be compromised. Moreover, the decreased monocytic HLA-DR expression suggests a post-operative immunosuppressed status in all patients, with a bigger impact by ACB, which might be attributed to the extracorporeal circulation or tissue damage occurring during surgery.

ASA Status, NPPA/NPPB Haplotype and Coronary Artery Disease Have an Impact on BNP/NT-proBNP Plasma Levels.

Plasma concentrations of natriuretic peptides (NP) contribute to risk stratification and management of patients undergoing non-cardiac surgery. However, genetically determined variability in the levels of these biomarkers has been described previously. In the perioperative setting, genetic contribution to NP plasma level variability has not yet been determined. A cohort of 427 patients presenting for non-cardiac surgery was genotyped for single-nucleotide polymorphisms (SNPs) from the NPPA/NPPB locus. Haplotype population frequencies were estimated and adjusted haplotype trait associations for brain natriuretic peptide (BNP) and amino-terminal pro natriuretic peptide (NT-proBNP) were calculated. Five SNPs were included in the analysis. Compared to the reference haplotype TATAT (rs198358, rs5068, rs632793, rs198389, rs6676300), haplotype CACGC, with an estimated frequency of 4%, showed elevated BNP and NT-proBNP plasma concentrations by 44% and 94%, respectively. Haplotype CGCGC, with an estimated frequency of 9%, lowered NT-proBNP concentrations by 28%. ASA classification status III and IV, as well as coronary artery disease, were the strongest predictors of increased NP plasma levels. Inclusion of genetic information might improve perioperative risk stratification of patients based on adjusted thresholds of NP plasma levels.

Real-time polymerase chain-reaction detection of pathogens is feasible to supplement the diagnostic sequence for urinary tract infections.

OBJECTIVE: To evaluate, in a prospective pilot study, the feasibility of identifying pathogens in urine using real-time polymerase chain reaction (PCR), and to compare the results with the conventional urine culture-based procedures. PATIENTS AND METHODS: Severe urinary tract infections (UTIs) are frequent in critically ill patients in the intensive-care unit (ICU) and in outpatients, and thus the reliable and fast identification of the bacteria is mandatory, but routine urine culture is time-consuming and the therapeutic regimen is often calculated and not culture-based. The study included 301 prospectively collected urine samples from 189 patients with suspected UTI, based in a university hospital in 2005, and included outpatients and those in the ICU. Urine culture with Cled-, MacConkey- and malt extract agar of all samples was followed by microbiological identification of the pathogens in 98 samples with visible growth. In parallel, all samples were assessed using qualitative real-time PCR-based DNA detection and identification by labelled hybridization probes. RESULTS: In all, 15 dipstick culture-negative samples showed positive pathogen DNA identification by PCR. By contrast, 17 PCR-negative samples showed detectable pathogens by culture, of which 10 were not detectable on PCR because the identified pathogens were not represented in the probe panel. The sensitivity and specificity for detecting contaminated samples was 0.90 and 0.87, respectively. Overall, 95% of the mono-infection pathogens and 57% of the multiple-infection pathogens were detected concordantly with both methods. CONCLUSION: In this prospective pilot study PCR-based identification of pathogens was feasible for supplementing conventional culture methods for the diagnosis of UTI. The main advantage is the time saved in identifying the pathogens. The limited pathogen detection in multiple-infection-samples by PCR might be explained by competitive PCR amplification conditions.

[Microbiological point of care tests]. / Point-of-Care-Monitoring - Mikrobiologische POC-Diagnostik.

It is well known that the early initiation of a specific antiinfective therapy is crucial to reduce the mortality in severe infection. Procedures culturing pathogens are the diagnostic gold standard in such diseases. However, these methods yield results earliest between 24 to 48 hours. Therefore, severe infections such as sepsis need to be treated with an empirical antimicrobial therapy, which is ineffective in an unknown fraction of these patients. Today's microbiological point of care tests are pathogen specific and therefore not appropriate for an infection with a variety of possible pathogens. Molecular nucleic acid diagnostics such as polymerase chain reaction (PCR) allow the identification of pathogens and resistances. These methods are used routinely to speed up the analysis of positive blood cultures. The newest PCR based system allows the identification of the 25 most frequent sepsis pathogens by PCR in parallel without previous culture in less than 6 hours. Thereby, these systems might shorten the time of possibly insufficient antiinfective therapy. However, these extensive tools are not suitable as point of care diagnostics. Miniaturization and automating of the nucleic acid based method is pending, as well as an increase of detectable pathogens and resistance genes by these methods. It is assumed that molecular PCR techniques will have an increasing impact on microbiological diagnostics in the future.

A MIF haplotype is associated with the outcome of patients with severe sepsis: a case control study.

BACKGROUND: Macrophage migration inhibitory factor (MIF) plays an important regulatory role in sepsis. In the promoter region a C/G single nucleotide polymorphism (SNP) at position -173 (rs755622) and a CATT5-8 microsatellite at position -794 are related to modified promoter activity. The purpose of the study was to analyze their association with the incidence and outcome of severe sepsis. METHODS: Genotype distributions and allele frequencies in 169 patients with severe sepsis, 94 healthy blood donors and 183 postoperative patients without signs of infection or inflammation were analyzed by real time PCR and Sequence analysis. All included individuals were Caucasians. RESULTS: Genotype distribution and allele frequencies of severe sepsis patients were comparable to both control groups. However, the genotype and allele frequencies of both polymorphisms were associated significantly with the outcome of severe sepsis. The highest risk of dying from severe sepsis was detectable in patients carrying a haplotype with the alleles -173 C and CATT7 (p = 0.0005, fisher exact test, RR = 1,806, CI: 1.337 to 2.439). CONCLUSION: The haplotype with the combination of the -173 C allele and the -794 CATT7 allele may not serve as a marker for susceptibility to sepsis, but may help identify septic patients at risk of dying.

Misplaced Ventricular Lead via an Atrial Septal Defect-Percutaneous Extraction.

Background Necessity for lead removal in this case was after 12 years due to mitral valve regurgitation caused by retraction of the posterior leaflet by the inadvertently misplaced lead. Case Description This history describes a 45-year-old woman with history of multiple cardiac operations at young age with an abandoned defibrillator lead via a patent atrial septal defect. Lead extraction was performed with first described use of rotational dilating sheaths to reduce emboli risk, hoping to avoid a fourth surgical procedure with high risk. Conclusions Percutaneous lead removal using rotational sheaths is possible even for misplaced leads after long-time intervals with acceptable operative risk.

Induction of Bim and Bid gene expression during accelerated apoptosis in severe sepsis.

INTRODUCTION: In transgenic animal models of sepsis, members of the Bcl-2 family of proteins regulate lymphocyte apoptosis and survival of sepsis. This study investigates the gene regulation of pro-apoptotic and anti-apoptotic members of the Bcl-2 family of proteins in patients with early stage severe sepsis. METHODS: In this prospective case-control study, patients were recruited from three intensive care units (ICUs) in a university hospital. Sixteen patients were enrolled when they fulfilled the criteria of severe sepsis. Ten critically ill but non-septic patients and 11 healthy volunteers served as controls. Blood samples were immediately obtained at inclusion. To confirm the presence of accelerated apoptosis in the patient groups, caspase-3 activation and phosphatidylserine externalisation in CD4+, CD8+ and CD19+ lymphocyte subsets were assessed using flow cytometry. Specific mRNAs of Bcl-2 family members were quantified from whole blood by real-time PCR. To test for statistical significance, Kruskal-Wallis testing with Dunn's multiple comparison test for post hoc analysis was performed. RESULTS: In all lymphocyte populations caspase-3 (p < 0.05) was activated, which was reflected in an increased phosphatidylserine externalisation (p < 0.05). Accordingly, lymphocyte counts were decreased in early severe sepsis. In CD4+ T-cells (p < 0.05) and B-cells (p < 0.001) the Bcl-2 protein was decreased in severe sepsis. Gene expression of the BH3-only Bim was massively upregulated as compared with critically ill patients (p < 0.001) and 51.6-fold as compared with healthy controls (p < 0.05). Bid was increased 12.9-fold compared with critically ill patients (p < 0.001). In the group of mitochondrial apoptosis inducers, Bak was upregulated 5.6-fold, while the expression of Bax showed no significant variations. By contrast, the pro-survival members Bcl-2 and Bcl-xl were both downregulated in severe sepsis (p < 0.001 and p < 0.05, respectively). CONCLUSIONS: In early severe sepsis a gene expression pattern with induction of the pro-apoptotic Bcl-2 family members Bim, Bid and Bak and a downregulation of the anti-apoptotic Bcl-2 and Bcl-xl proteins was observed in peripheral blood. This constellation may affect cellular susceptibility to apoptosis and complex immune dysfunction in sepsis.

Oxidoreductase Macrophage Migration Inhibitory Factor is simultaneously increased in leukocyte subsets of patients with severe sepsis.

The oxidoreductase Macrophage Migration Inhibitory Factor (MIF) is discussed as a promising target for immunomodulatory therapy in patients with severe sepsis. Moreover, MIF expresses tautomerase as well as thiol-protein oxidoreductase activities and has a potential role in cellular redox homeostasis, apoptosis inhibition, endotoxin responsiveness as well as regulation of nuclear transcription factors. To further elucidate a potential role of intracellular MIF in severe sepsis, we assessed alterations of intracellular MIF content in peripheral blood leukocytes of patients with severe sepsis in comparison to healthy controls and non-septic patients after major surgery. Intracellular MIF was significantly elevated simultaneously in lymphocytes, B-cells, macrophages and granulocytes of patients with severe sepsis when compared to healthy control individuals (p < 0.05) and increased when compared to non-septic patients after major surgery. In parallel, plasma MIF levels were elevated in severe sepsis (p < 0.05). There was no difference of intracellular MIF in lymphocytes, B-cells, macrophages or granulocytes between surviving and non-surviving patients with severe sepsis (p > 0.05). However, in survivors LPS ex vivo stimulation increased MIF secretion but not in non-survivors of sepsis (p < 0.05). This finding underlines the role of intracellular MIF in inflammatory diseases. It suggests monitoring of intracellular MIF in further clinical and non-clinical research valuable.

Low serum alpha-tocopherol and selenium are associated with accelerated apoptosis in severe sepsis.

During sepsis, a severe systemic disorder, micronutrients often are decreased. Apoptosis is regarded as an important mechanism in the development of often significant immunosuppression in the course of the disease. This study aimed to investigate alpha-tocopherol and selenium in reference to apoptosis in patients with sepsis. 16 patients were enrolled as soon as they fulfilled the criteria of severe sepsis. 10 intensive care patients without sepsis and 11 healthy volunteers served as controls. alpha-Tocopherol, selenium and nucleosomes were measured in serum. Phosphatidylserine externalization and Bcl-2 expression were analyzed in T-cells by flow cytometry. Serum alpha-tocopherol and selenium were decreased in severe sepsis but not in non-septic critically ill patients (p < 0.05). Conversely, markers of apoptosis were increased in sepsis but not in critically ill control patients: Nucleosomes were found to be elevated 3 fold in serum (p < 0.05) and phosphatidylserine was externalized on an expanded subpopulation of T-cells (p < 0.05) while Bcl-2 was expressed at lower levels (p < 0.05). The decrease of micronutrients correlated with markers of accelerated apoptosis. Accelerated apoptosis in sepsis is associated with low alpha-tocopherol and selenium. The results support the investigation of micronutrient supplementation strategies in severe sepsis.

Retrograde type a dissection in a 24th gestational week pregnant patient - the importance of interdisciplinary interaction to a successful outcome.

BACKGROUND: Type A Dissection in pregnancy is a devastating medical condition with 2 lives at stake and unclear strategy at early gestational stages. We describe a successful outcome, clearly dependent on the coordination of all involved disciplines. CASE PRESENTATION: This case history describes a 28 year old female with a 24th week pregnancy gravida 2 para 0 with a DeBakey Type I aortic dissection, diagnosed via ultrasound. Surgery was perfomed on the day of diagnosis. After conferral with the mother, caesarean section was performed and a 690 g fetus could be delivered and was immediately transferred to the neonatal unit. Subsequent aortic repair was performed after hysterectomy, with replacement of the ascending aorta and hemiarch treatment. Intraoperatively no entry in the ascending aorta or transverse arch could be demonstrated, so that a retrograde Type A with entry distal to the left subclavian had to be postulated. We decided to perform subsequent computer tomography, demonstrating multiple entry sites in the descending aorta distal to the left subclavian artery. Successful endovascular treatment could be performed with a Medtronic Valiant Stent via a transfemoral approach. The further hospital stay was uneventful and the patient could be discharged on the 18th postoperative day. The baby demonstrated fighter qualities and could be discharged home after a 3 month hospital stay to be reunited with his mother. CONCLUSION: Prompt diagnosis, precise coordination between all involved subspecialties and ultimately, as in this case, definitive treatment in consensus with operative and interventional departments have led to a successful outcome and encourages us in our daily struggle in this often demanding surgery.

Urgent Endovascular Treatment for Non-traumatic Descending Thoracic Aortic Rupture.

PURPOSE: To evaluate the efficacy of endovascular repair of non-traumatic rupture of the descending thoracic aorta. MATERIALS AND METHODS: From January 2011 to August 2017, 22 consecutive patients (16 men, mean age 73.7 years, range 63-92 years) with non-traumatic rupture of the descending thoracic aorta were treated endovascularly. Thirty-day mortality as well as procedure-related morbidity including stroke, renal, pulmonary and spinal complications were retrospectively assessed. Median follow-up was 29 months (range 6-65 months). RESULTS: Nine patients had type B dissections, and 13 had atherosclerotic aortic aneurysms. The technical success was 100%; 86.3% of patients (19/22) were treated percutaneously. Thirteen patients (59%) received a single endograft, 8 (36%) received 2 endografts, and 1 received 3 endografts. The endograft diameters ranged between 28 and 46 mm. Two dissection patients received additional distal bare metal true lumen stents. Eleven patients required additional drainage of thoracic hematoma. Three primary percutaneous sites (15.7%) required surgical revision. No spinal cord ischemic or renal complications were observed. Stroke was observed in 2 patients (9%), both with full coverage of left subclavian artery origin. Four patients (18%) required tracheostomy with prolonged respiratory support (range 10-15 days). The median intensive care unit stay was 5 days (range 1-27 days). The 30-day mortality was 18.1% (4/22). CONCLUSION: Endoluminal repair of non-traumatic rupture of the descending thoracic aorta can be performed percutaneously. It showed a 30-day mortality of 18.1%, and no spinal cord injury or renal complications were observed in surviving patients at follow-up. LEVEL OF EVIDENCE: Level 4, case series.

Inducibility of the endogenous antibiotic peptide beta-defensin 2 is impaired in patients with severe sepsis.

INTRODUCTION: The potent endogenous antimicrobial peptide human beta-defensin 2 (hBD2) is a crucial mediator of innate immunity. In addition to direct antimicrobial properties, different effects on immune cells have been described. In contrast to the well-documented epithelial beta-defensin actions in local infections, little is known about the leukocyte-released hBD2 in systemic infectious disorders. This study investigated the basic expression levels and the ex vivo inducibility of hBD2 mRNA in peripheral whole blood cells from patients with severe sepsis in comparison to non-septic critically ill patients and healthy individuals. METHODS: This investigation was a prospective case-control study performed at a surgical intensive care unit at a university hospital. A total of 34 individuals were tested: 16 patients with severe sepsis, 9 critically ill but non-septic patients, and 9 healthy individuals. Serial blood samples were drawn from septic patients, and singular samples were obtained from critically ill non-septic patients and healthy controls. hBD2 mRNA levels in peripheral white blood cells were quantified by real-time polymerase chain reaction in native peripheral blood cells and following ex vivo endotoxin stimulation. Defensin plasma levels were quantified by enzyme-linked immunosorbent assay. RESULTS: Endotoxin-inducible hBD2 mRNA expression was significantly decreased in patients with severe sepsis compared to healthy controls and non-septic critically ill patients (0.02 versus 0.95 versus 0.52, p < 0.05, arbitrary units). hBD2 plasma levels in septic patients were significantly higher compared to healthy controls and critically ill non-septic patients (541 versus 339 versus 295 pg/ml, p < 0.05). CONCLUSION: In contrast to healthy individuals and critically ill non-septic patients, ex vivo inducibility of hBD2 in peripheral blood cells from septic patients is reduced. Impaired hBD2 inducibility may contribute to the complex immunological dysfunction in patients with severe sepsis.