Rlangen, Germany; Department of Orthopaedic Surgery, University of Erlangen-Nuremberg, Germany Introduction: Nelociguat site During insertion of a cemented total hip arthroplasty, the rise of the intramedullary pressure in the femur, causes embolisation of fat and bone marrow into the pulmonary circulation. The goal of this study was to relate the embolic events observed by transesophageal echocardiography to the changes in hemodynamic, hemogasanalytic, and calculated pulmonary shunt values. Material and methods: In this clinical trial entered 65 patients (> 65 years). During the surgical period continually monitoring included ECG, measurement of invasive arterial pressure, pulsoximetric oxigen saturation, endtidal carbondioxid concentration as well as transesophageal echo-cardiography. A blinded observer graded embolic events from videotapes off-line after published criteria [1]. Hemogasanalysis was performed at defined points of the perioperative period. Preoperative clinical status of the patients was assessed according to the classification of the ASA. Pulmonary shunt-values were calculated with the formula of Ries et al [2]. Results: Cementation of the stem caused a cascade of fine emboli of less than 5 mm with an opacification of the right atrium and ventricle. In the same set of patients, after reduction of the hip joint, it was followed by macroemboli up to 3 cm (49 patients, 75 ). No important embolic phenomena were observed during other surgical steps. Both embolic events were followed by changes in hemodynamics (increase in heart rate in 18 , P < 0.05; hypotension more than 20 mmHg in 62 ) and blood gas parameters (paO2 decreased for 7.7 , 41.4 mmHg; P < 0.05). PetCO2 decreased for a mean of 2.9 mmHg (P < 0.05). Pulmonary shunt values increased after embolisation for a mean of 30.5 (P < 0.05). They did not turn back to baseline values in the postoperative period in patients classified PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/20718690 ASA III and IV. A significant correlation (P < 0.05) was found between the clinical state before surgery and the duration and intensity of hemogasanalytic changes after insertion of the stem. Conclusion: There is a correlation between embolic events quantified by transesophageal echo-cardiography and the grade of hemodynamic and haemogasanalytic changes of patients during cemented total hip arthroplasty. Patients with high anasthesiological risk can suffer severe cardiopulmonary complications from fat and bone marrow embolisation, that last even into the postoperative period and may cause intesive care treatment.After resuscitation all patients showed increased PAPsys higher than 50 mmHg, CI lower than 2.5 and SVO2 lower than 75 . All patients were treated with administration of rt-PA in fraction of 5 mg each 90 s. Success of lysis was shown by angiography and right-ventricular monitoring. Results: By four patients there was a rapid normalisation after administration of highest 15 mg rt-PA. The result was to be seen first at angiography than on SVO2. Cardiac parameters took 5? min to normalize. One patient needs administration of 40 mg rt-PA for normalization. One patient died during lysis without any remarkable normalization and after unsuccessful resuscitation.SDiscussion: It was shown that continous right-ventricular monitoring is a capable feature for monitoring during lysis at thecritically ill patient. Even angiography is more sensitive the SVO2-monitoring provides usefull information. If there is no way to have an angiography, right-ventricular monitori.