Karin Engström1, Karl Gunnar Engström. 1. Department of Public Health and Caring Sciences/Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden. gunnar.engstrom@vll.se
Abstract
OBJECTIVES: Electrocautery is an appreciated surgical tool, which however, generates immense heat and fat-tissue melting. In cardiac surgery, liquefied fat collects on the surface of blood in the pericardial cavity and becomes aspirated by the heart-lung machine for aortic recycling. Deposits seen in the brain microcirculation after surgery are caused by lipid embolism. This study investigates lipid chemistry, whether heat from electrocautery generates fatty-acid fragmentation and decomposition. DESIGN: Pericardial fat tissue was sampled from cardiac-surgery patients and from piglets. The human tissue was exposed to electrocautery, or to fixed temperatures in an in vitro model. Fatty-acid decomposition was explored by solid-phase microextraction gas chromatography and the distribution of fatty acids was measured. RESULTS: Fatty-acid decomposition demonstrated a temperature-effect relationship (p = 0.007). At 350°C the proportion of polyunsaturated fatty acids became heavily reduced or were abolished (p = 0.016). Electrocautery resulted in similar changes. CONCLUSIONS: Electrocautery induces a profound fatty-acid fragmentation to form short-chained compounds. The chemical and toxic nature of these compounds remains to be determined, including their clinical implications at blood recycling in cardiac surgery.
OBJECTIVES: Electrocautery is an appreciated surgical tool, which however, generates immense heat and fat-tissue melting. In cardiac surgery, liquefied fat collects on the surface of blood in the pericardial cavity and becomes aspirated by the heart-lung machine for aortic recycling. Deposits seen in the brain microcirculation after surgery are caused by lipid embolism. This study investigates lipid chemistry, whether heat from electrocautery generates fatty-acid fragmentation and decomposition. DESIGN: Pericardial fat tissue was sampled from cardiac-surgery patients and from piglets. The human tissue was exposed to electrocautery, or to fixed temperatures in an in vitro model. Fatty-acid decomposition was explored by solid-phase microextraction gas chromatography and the distribution of fatty acids was measured. RESULTS:Fatty-acid decomposition demonstrated a temperature-effect relationship (p = 0.007). At 350°C the proportion of polyunsaturated fatty acids became heavily reduced or were abolished (p = 0.016). Electrocautery resulted in similar changes. CONCLUSIONS: Electrocautery induces a profound fatty-acid fragmentation to form short-chained compounds. The chemical and toxic nature of these compounds remains to be determined, including their clinical implications at blood recycling in cardiac surgery.