title: The clinical relevance of embolic events detected by transesophageal echocardiography during cemented total hip arthroplasty: a randomized clinical trial.
abstract: The first aim of this prospective clinical study was to characterize the relationship between embolic events observed during cemented total hip arthroplasty using transesophageal echocardiography (TEE), and changes in cardiopulmonary function. The second aim was to assess the efficiency of a modified cementing technique that was developed to reduce the risk of embolism. The modification consists in a vacuum drainage placed in the proximal femur to reduce the increase of intramedullary pressure during insertion of the prosthesis. One hundred twenty patients were randomized into two groups. Group 1 received a total hip arthroplasty cemented conventionally, whereas Group 2 was cemented with the modified technique. Continuous TEE, hemodynamic monitoring, and blood gas analysis were done during the perioperative period. Severe embolic events were imaged during the insertion of the femoral component and the reduction of the hip joint. Embolism occurred in 93.3% of patients operated on with the conventional cementing technique, compared with 13.3% of patients operated on with the modified technique (P < 0.05). Intraoperative shunt values during insertion of the femoral component increased from 8.2% to 10.3% (P < 0.05) in Group 1 patients, whereas there was no significant change in Group 2 patients. We observed no clinical signs of fat embolism syndrome in any study patient. The results of the study indicate that embolic events observed using TEE can cause increased pulmonary shunt values during hip arthroplasty, especially in patients with systemic disease (ASA physical status III). The modified surgical technique effectively reduced the incidence of embolization during cemented hip arthroplasty.
  
  
  CONCLUSIONS
  Use of conventional cementing techniques is associated with echocardiographic evidence of embolism in 93% of patients and with a significant increase in pulmonary shunting. The incidence of embolism and change in shunting are reduced with a modified cementing technique that limits increases in intramedullary pressure.
authors.affiliation: Department of Anesthesiology, Waldkrankenhaus, Erlangen, Germany.
authors.forename: M J
authors.initials: MJ
authors.lastname: Koessler
authors.forename: R
authors.initials: R
authors.lastname: Fabiani
authors.forename: H
authors.initials: H
authors.lastname: Hamer
authors.forename: R P
authors.initials: RP
authors.lastname: Pitto
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000379:methods*; D001843:Bone Cements; D002484:Cementation / Q000379:methods; D017548:Echocardiography, Transesophageal; D004620:Embolism, Fat / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D016343:Monitoring, Intraoperative / Q000379:methods; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D012129:Respiratory Function Tests
chemical_list: D001843:Bone Cements