title: Transoesophageal echocardiography shows high risk of gas embolism during laparoscopic hepatic resection under carbon dioxide pneumoperitoneum.
abstract: BACKGROUND
  The ultrasonically activated scalpel (UAS) enables safe and effective laparoscopic tissue dissection, making hepatic resection feasible. This study compared blood loss and risk of gas embolism using the UAS during open hepatic resection and laparoscopic hepatic resection.
  
  
  METHODS
  Female pigs were divided into two groups for laparoscopic (n = 7) and open (n = 5) left hepatic lobectomy. The UAS was used for both tissue cutting and coagulation. Laparoscopic liver resection was performed under carbon dioxide pneumoperitoneum (intraperitoneal pressure 12 mmHg). During surgery animals were monitored haemodynamically by an arterial line and Swan-Ganz catheter. Two-dimensional transoesophageal echocardiography (2D-TEE) was used to detect gas emboli with special attention to the right atrium and ventricle. Gas emboli were graded according to size, and correlated with haemodynamic and blood gas data.
  
  
  RESULTS
  During open and laparoscopic hepatic resection the UAS resulted in minimal blood loss and effective tissue dissection. No air embolism was seen during open surgery. With laparoscopic hepatic resection 2D-TEE revealed gas embolism in all animals. Gas embolism was accompanied by cardiac arrhythmia in four of seven animals. No direct correlation was observed between embolism episodes and blood gas variables. There were no deaths after episodes of embolization. A significant decrease in arterial partial pressure of oxygen was seen at the end of the laparoscopic procedure in all animals.
  
  
  CONCLUSIONS
  The UAS causes minimal blood loss during both open and laparoscopic hepatic resection. Laparoscopic liver dissection under carbon dioxide pneumoperitoneum carries a high risk of gas embolism.
authors.affiliation: Department of Surgery, Johann Wolfgang Goethe University Hospital, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany. schmandra@em.uni-frankfurt.de
authors.forename: T C
authors.initials: TC
authors.lastname: Schmandra
authors.forename: S
authors.initials: S
authors.lastname: Mierdl
authors.forename: H
authors.initials: H
authors.lastname: Bauer
authors.forename: C
authors.initials: C
authors.lastname: Gutt
authors.forename: E
authors.initials: E
authors.lastname: Hanisch
mesh_terms: D000818:Animals; D016063:Blood Loss, Surgical; D002245:Carbon Dioxide / Q000009:adverse effects* / Q000627:therapeutic use; D017548:Echocardiography, Transesophageal / Q000379:methods*; D004618:Embolism, Air / Q000209:etiology*; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D010535:Laparoscopy / Q000009:adverse effects* / Q000379:methods; D008099:Liver / Q000601:surgery*; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D012307:Risk Factors; D013552:Swine
chemical_list: D002245:Carbon Dioxide