HARMFUL EFFECTS OF INVASIVE ANIMAL MONITORING ON MUSCLE FLAP MICROCIRCULATION

In this study, peripheral microcirculatory response to arterial and ve nous cannulation was studied. Eleven Sprague-Dawley rats were evaluate d in two groups. Group I was the control group and received no cannula tion (N = 6). After cremaster muscle isolation, the following paramete rs were evaluated at the microcirculatory level: vessel diameters, red blood cell (RBC) velocities, capillary density, and leukocyte and lym phocyte behavior (rollers, stickers, transmigrating white blood cell [ WBC]). In group II, vessel cannulation was performed (N = 5). Before c remaster muscle isolation, the right femoral artery was cannulated for mean arterial blood pressure measurements; the right carotid artery w as cannulated for arterial partial oxygen pressure (PaO2), arterial pa rtial carbon dioxide pressure (PaCO2), and pH measurements; and the le ft jugular vein was cannulated for central venous pressure evaluation. Microcirculatory measurements as in group I were also taken. In the c annulated animals, arterial RBC velocity was 18.1% faster, whereas ven ous RBC velocity was 15.7% decreased (p < 0.05). In addition, leukocyt e activation increased and was confirmed by a 254.6% rise in rolling l eukocytes, a 59.7% increase in rolling lymphocytes, and a 67.2% increa se in leukocyte ''stickers'' (p < 0.05). In group II, functional capil lary perfusion was decreased by 44.9%, and 4.8% higher endothelial ede ma indexes were found (p < 0.05). In conclusion, this study has proven that, despite its clinical importance during vital signs monitoring, cannulation procedures may significantly impair peripheral microcircul atory hemodynamics. For this reason, cannulation procedures should be designed with caution and should be reported in experimental methods.