Non-thyroidal Illness Syndrome (NTIS) is no independent predictor for mortality in ICU patients.

BACKGROUND: Low T3-(/T4-) syndrome, also known as non-thyroidal Illness Syndrome (NTIS) describes a decrease in free serum thyroid hormones without a concomitant increase in TSH, frequently observed in critically ill patients. However, whether NTIS is only a metabolic adaption to stress in critically ill or plays a crucial role as an independent risk factor for ICU mortality, remains unknown. Our study aimed to evaluate NTIS as an independent risk factor for increased ICU mortality. METHODS: All patients admitted to the interdisciplinary intensive care unit (ICU) at the University Hospital of Leipzig between 2008 and 2014 were retrospectively analyzed for thyroidal function. Baseline data, information on additional thyroid function tests, disease progression, hospital and ICU length of stay (LOS) and patient outcome were retrospectively analyzed from the hospitals digital information system. For statistical evaluation, univariate analysis, matched pairs analysis and multivariate logistic regression were conducted. RESULTS: One thousand, seven hundred ninety patients were enrolled in the study, of which 665 showed NTIS. Univariate analysis revealed a positive association of NTIS with ICU- and hospital-LOS, need for mechanical ventilation, incidence of sepsis, acute respiratory distress syndrome, acute liver failure and increased ICU mortality. Results of matched pair analysis confirmed these findings. In multivariate logistic regression, NTIS was associated with an increased ICU-LOS, increased duration of mechanical ventilation, acute kidney injury and liver failure, but showed no independent association with increased ICU-mortality. CONCLUSION: Duration of mechanical ventilation as well as incidence of acute kidney injury, sepsis and acute liver failure were detected as independent predictors of mortality in patients with NTIS. NTIS itself was no independent predictor of increased ICU-mortality.

The Influence of Positive End-Expiratory Pressure on Leakage and Oxygenation Using a Laryngeal Mask Airway: A Randomized Trial.

BACKGROUND: The value of positive end-expiratory pressure (PEEP) in maintaining oxygenation during ventilation with a laryngeal mask airway (LMA) mask is unclear. To clarify the potential benefit or harm to PEEP application during positive pressure ventilation with a ProSeal LMA® mask, we compared the effect of PEEP versus zero end-expiratory pressure (ZEEP) on gas leakage and oxygenation. We hypothesized that a PEEP of 8 mbar (8.2 cm H 2 O) would be associated with an increased incidence of gas leakage compared to ZEEP. METHODS: We designed a prospective, controlled, randomized, single-blinded, multicenter clinical trial. Patients >18 years of age with an American Society of Anesthesiologists (ASA) physical status I/II without increased risk of aspiration were enrolled if they were scheduled for elective surgery under general anesthesia with an LMA mask. Patients were randomized to a control group managed with ZEEP or an intervention group managed with a PEEP of 8 mbar. Both groups received positive pressure ventilation. The primary end point was the occurrence of gas leakage. The Student t test and χ 2 test were used for statistical analysis. RESULTS: A total of 174 patients were enrolled in the ZEEP group, and 208 were enrolled in the PEEP group. The incidence of gas leakage did not differ between the 2 groups (ZEEP: 23/174, 13.2%; PEEP: 42/208, 20.2%; P = .071; odds ratio [OR], 1.611; 95% confidence interval [CI], 0.954-2.891). However, more patients required reseating of the LMA mask in the PEEP group (ZEEP: 5/174, 2.9%; PEEP: 18/208, 8.7%; P = .018; OR, 3.202; 95% CI, 1.164-8.812). The need for endotracheal intubation did not differ between groups (ZEEP: 2/174, 1.1%; PEEP: 7/208, 3.4%; P = .190; OR, 2.995; 95% CI, 0.614-14.608). After positive pressure ventilation for 25 minutes, the mean peripheral oxygen saturation (Sp o2 ) was higher in the PEEP than in the ZEEP group (98.5 [1.9]% vs 98.0 [1.4]%; P = .01). Peak inspiratory pressure (PIP; 16 [2] vs 12 [4] mbar; P < .001) and dynamic compliance (57 [14] vs 49 [14] mL/mbar; P < .001) were both higher in the PEEP group than in the ZEEP group. CONCLUSIONS: Use of PEEP did not affect the overall incidence of gas leakage. However, PEEP did result in a higher incidence of attempts to reseat the LMA mask compared to ZEEP, whereas the incidence of rescue intubation did not differ between groups. We concluded that a PEEP of 8 mbar did not increase overall gas leakage during positive pressure ventilation with an LMA mask, but it did slightly improve gas exchange and compliance. Overall, our study does not provide strong arguments for using PEEP during ventilation with an LMA mask in elective surgery.

Influence of Ethylene Oxide and Gamma Irradiation Sterilization Processes on the Properties of Poly-L-Lactic-Acid (PLLA) Materials.

In order to encourage the substitution of petrochemical polymers in medical technology with sustainable, bio-based materials, there is an urgent need for further investigations, especially data regarding their sterility performance. Within the scope of the investigations, selected material properties of poly-L-lactic-acid (PLLA), a specific type of poly(lactic-acid) (PLA), were analyzed before and after sterilization (using ethylene oxide or gamma irradiation) in order to investigate deviations in its chemical structure, wettability, optical, and mechanical properties. In particular, parameters such as molecular weight, complex viscosity, tensile strength, water contact angle, and color were discussed. Sterilization temperatures close to the glass transition of PLA, high humidity, and interactions with the ethylene oxide molecules have resulted in an increase in crystallinity, a decrease in elongation at break, and in some cases, a variation in wettability. As a consequence of exposure to high-energy radiation, the material's toughness is reduced due to chain scission, which is manifested through a decrease in molecular weight, an increase in crystallinity, and a partial change in surface energy. For the selected PLLA-materials (Luminy® L130, NP HT 202, and NP HT 203), ethylene oxide sterilization resulted in a comparatively minor variation in the characteristics behavior, and was chosen as the preferred method.