Echocardiography predictors of sustained sinus rhythm after cardioversion of supraventricular arrhythmia in patients with septic shock.

PURPOSE: The echocardiography parameters may predict the maintenance of sinus rhythm after cardioversion of a supraventricular arrhythmia (SVA). MATERIALS AND METHODS: Patients in septic shock with onset of an SVA, normal to moderately reduced LV systolic function (EF_LV˃̳35%) and on a continuous noradrenaline of <1.0 µg/kg.min were included. Echocardiography was performed at the arrhythmia onset, 1 h and 4 h post cardioversion on an infusion of propafenone or amiodarone. RESULTS: Cardioversion was achieved in 96% of the 209 patients within a median time of 6(1.8-15.6)h, 134(64.1%) patients experienced at least one SVA recurrence after cardioversion. At 4 h the left atrial emptying fraction (LA_EF, cut-off 38.4%, AUC 0.69,p˂0.001), and transmitral A wave velocity-time-integral (Avti, cut-off 6.8 cm, AUC 0.65,p = 0.001) showed as limited predictors of a single arrhythmia recurrence. The LA_EF 44(36,49)%, (p = 0.005) and the Avti 8.65(7.13,9.50)cm, (p < 0.001) were associated with sustained sinus rhythm and decreased proportionally to increasing numbers of arrhythmia recurrences (p < 0.001 and p = 0.007, respectively). The enlarged left atrial end-systolic diameter at the arrhythmia onset (p = 0.04) and elevated systolic pulmonary artery pressure at 4 h (p = 0.007) were weak predictors of multiple(˃3) recurrences. CONCLUSION: The LA_EF and Avti are related to arrhythmia recurrences post-cardioversion suggesting potential guidance to the choice between rhythm and rate control strategies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03029169, registered on 24th of January 2017.

The impact of obesity on the outcome of severe SARS-CoV-2 ARDS in a high volume ECMO centre: ECMO and corticosteroids support the obesity paradox.

PURPOSE: The aim was to verify the impact of obesity on the long-term outcome of patients with severe SARS-CoV-2 ARDS. MATERIALS AND METHODS: The retrospective study included patients admitted to the high-volume ECMO centre between March 2020 and March 2022. The impact of body mass index (BMI), co-morbidities and therapeutic measures on the short and 90-day outcomes was analysed. RESULTS: 292 patients were included, of whom 119(40.8%) were treated with veno-venous ECMO cannulated mostly (73%) in a local hospital. 58.5% were obese (64.7% on ECMO), the ECMO was most frequent in BMI > 40(49%). The ICU mortality (36.8% for obese vs 33.9% for the non-obese, p = 0.58) was related to ECMO only for the non-obese (p = 0.04). The 90-day mortalities (48.5% obese vs 45.5% non-obese, p = 0.603) of the ECMO and non-ECMO patients were not significantly influenced by BMI (p = 0.47, p = 0.771, respectively). The obesity associated risk factors for adverse outcome were age <50 (RR 2.14) and history of chronic immunosuppressive therapy (RR 2.11, p = 0.009). The higher dosage of steroids (RR 0.57, p = 0.05) associated with a better outcome. CONCLUSIONS: The high incidence of obesity was not associated with worse short and long-term outcomes. ECMO in obese patients together with the use of steroids in the later stage of ARDS may improve survival.

Liquid resorbable nanofibrous surgical mesh: a proof of a concept.

BACKGROUND: Surgical mesh is widely used not only to treat but also to prevent incisional hernia formation. Despite much effort by material engineers, the 'ideal' mesh mechanically, biologically and surgically easy to use remains elusive. Advances in tissue engineering and nanomedicine have allowed new concepts to be tested with promising results in both small and large animals. Abandoning the concept of a pre-formed mesh completely for a 'pour in liquid mesh' has never been tested before. MATERIALS AND METHODS: Thirty rabbits underwent midline laparotomy with closure using an absorbable suture and small stitch small bites technique. In addition, their abdominal wall closure was reinforced by a liquid nanofibrous scaffold composed of a fibrin sealant and nanofibres of poly-ε-caprolactone with or without hyaluronic acid or the sealant alone, poured in as an 'onlay' over the closed abdominal wall. The animals were killed at 6 weeks and their abdominal wall was subjected to histological and biomechanical evaluations. RESULTS: All the animals survived the study period with no major complication. Histological evaluation showed an eosinophilic infiltration in all groups and foreign body reaction more pronounced in the groups with nanofibres. Biomechanical testing demonstrated that groups treated with nanofibres developed a scar with higher tensile yield strength. CONCLUSION: The use of nanofibres in a liquid form applied to the closed abdominal wall is easy to use and improves the biomechanical properties of healing fascia at 6 weeks after midline laparotomy in a rabbit model.

Dynamic creep properties of a novel nanofiber hernia mesh in abdominal wall repair.

PURPOSE: Incisional hernia is the most common complication following abdominal surgery. While mesh repair is common, none of the current meshes mimic the physiology of the abdominal wall. This study compares suture only repair with polypropylene mesh and a prototype of a novel implant (poly-epsilon-caprolactone nanofibers) and their influence on the physiology of an abdominal wall in an animal model. METHODS: 27 Chinchilla rabbits were divided into six groups based on the type of the implant. Midline abdominal incision was repaired using one of the compared materials with suture alone serving as the control. 6 weeks post-surgery animals were killed and their explanted abdominal wall subjected to biomechanical testing. RESULTS: Both-hysteresis and maximum strength curves showed high elasticity and strength in groups where the novel implant was used. Polypropylene mesh proved as stiff and fragile compared to other groups. CONCLUSION: Poly-epsilon-caprolactone nanofiber scaffold is able to improve the dynamic properties of healing fascia with no loss of maximum tensile strength when compared to polypropylene mesh in an animal model.

A novel experimental model of acute respiratory distress syndrome in pig.

Acute respiratory distress syndrome (ARDS) is severe medical condition occurring in critically ill patients and with mortality of 33-52 % is one of the leading causes of death in critically ill patients. To better understand pathophysiology of ARDS and to verify novel therapeutical approaches a reliable animal model is needed. Therefore we have developed modified lavage model of ARDS in the pig. After premedication (ketamine and midazolam) 35 healthy pigs were anesthetized (propofol, midazolam, morphin, pipecuronium) and orotracheally intubated and ventilated. Primary ARDS was induced by repeated cycles of lung lavage with a detergent Triton X100 diluted in saline (0.03 %) heated to 37 °C preceded by pre-oxygenation with 100 % O(2). Single cycle included two subsequent lavages followed by detergent suction. Each cycle was followed by hemodynamic and ventilation stabilization for approx. 15 min, with eventual administration of vasopressors according to an arterial blood pressure. The lavage procedure was repeated until the paO(2)/FiO(2) index after stabilization remained below 100 at PEEP 5 cm H(2)O. In 33 pigs we have achieved the desired degree of severe ARDS (PaO(2)/FiO(2)<100). Typical number of lavages was 2-3 (min. 1, max. 5). Hemodynamic tolerance and the need for vasopressors were strongly individual. In remaining two animals an unmanageable hypotension developed. For other subjects the experimental ARDS stability was good and allowed reliable measurement for more than 10 h. The present model of the ARDS is clinically relevant and thus it is suitable for further research of the pathophysiology and management of this serious medical condition.

[Vascularization of the lateral heel in relation to extensive skin incisions in osteosynthesis of calcaneal fractures]. / Vaskularizace laterální strany paty ve vztahu k extenzivnímu koznímu rezu k osteosyntéze zlomeniny kalkanea.

The aim of the study was to document soft tissue vascularization of the lateral heel on cadavers and, therefore, to indirectly demonstrate the importance to perform perfectly precise incisions, in order to prevent ischemic complications. Sections of 8 human lower limb cadavers were performed in cooperation with the Anatomical Institute of the MU Medical Faculty in Brno, according to current common standards for anatomical preparations. In successive steps, cutaneous and subcutanous covers of the lateral ankle, malleolar and heel regions were preparated. Final branches of the individual arteries were followed and the authors aimed to demonstrate their vascular arcade consisting of anastomosis of the lateral calcaneal artery--LCA (a branch of a. peronea)--which is a clinical term for rami calcaneares laterales, ventrolateral tarsal arteries--LTA (a branch of a. dorsalis pedis) and lateral malleolar artery branching off medially--LMA (a branch of a. tibialis ant.). The course of the arteries and their location is related to a reference point--a lateral tip of the lateral ankle. The investigators found out that all three arteries, as well as the arterial arch, had standard courses. The course of the arch defines the outline of the lateral extensive incision during osteosynthesis in calcaneal fractures, which lies fairly close to the lateral outline of this vascular arcade. Incorrect performance of the incision results, invitably, in serious ischemic complications. Open reduction and internal fixation of intraarticular calcaneal fractures has become a standard surgical method. Correct indication, good timing and saving open reduction, internal fixation using arthroscopy and early mobilization are the prerequisites to prevent further postoperative complications and to achieve complete healing of the fracture. Considering the demandingness of these fractures treatment and their rare incidence, their management should be centred in specialized traumatological clinics.

Ultrasound estimation of volume of pleural fluid in mechanically ventilated patients.

OBJECTIVE: The aim was to develop a practical method for estimation of the volume of pleural effusion using ultrasonography in mechanically ventilated patients. DESIGN: Prospective observational study. SETTING: 20-bed general intensive care unit in the university hospital. PATIENTS AND PARTICIPANTS: 81 patients were included after initial suspicion of pleural fluid on chest supine X-ray and pre-puncture ultrasound confirming effusion. Patients with thoracic deformities, post-lung surgery, with diaphragm pathology, haemothorax, empyema and with incomplete aspiration of pleural fluid on post-puncture ultrasound were excluded. INTERVENTIONS: Patients were supine with mild trunk elevation at 15 degrees . Probe was moved upwards in posterior axillary line, and transverse section perpendicular to the body axis was obtained with pleural separation visible at lung base. The maximal distance between parietal and visceral pleura (Sep) in end-expiration was recorded. Thoracentesis was performed at previous probe position and volume of pleural fluid (V) recorded. MEASUREMENTS AND RESULTS: 92 effusions were evaluated and drained; 11 (12%) were excluded for incomplete aspiration. Success rate of obtaining fluid under ultrasound guidance was 100%; the incidence of pneumothorax or bleeding was zero. Mean Sep was 35+/-13 mm. Mean V was 658+/-320 ml. Significant positive correlation between both Sep and V was found: r=0.72; r(2)=0.52; p<0.001. The amount of pleural fluid volume can be estimated with the simplified formula: V (ml)=20 x Sep (mm). Mean prediction error of V using Sep was 158.4+/-160.6 ml. CONCLUSIONS: Easy quantification of pleural fluid may help to decide about performing thoracentesis in high-risk patients, although thoracentesis under ultrasound guidance appears to be a safe procedure.