Effects of halothane and isoflurane anaesthesia on microcirculatory blood flow in musculocutaneous flaps
SIGURDSSON, G. H. ; BANIC, A. ; WHEATLEY, A. M. ; METTLER, D.
In: BJA: British Journal of Anaesthesia, 1994, vol. 73, no. 6, p. 826-832
Zum persönliche Liste hinzufügen- Summary
- Hypoperfusion and necrosis in musculocutaneous flaps used for reconstruction of tissue defects is still a significant clinical problem. Although the causes of hypoperfusion are frequently surgical in nature, little is known about the effects of anaesthetic management on blood flow in flaps or the outcome of flap surgery. We compared in minipigs the effects of halothane and isoflurane anaesthesia in equipotent doses on microcirculatory blood flow (MBF) in the skin and muscle part of musculocutaneous flaps and also in intact (control) skin and muscle. Measurements were made during stable normovolaemic conditions and during mild to moderate hypovolaemia (withdrawal of 5%, 10% and 15% of total blood volume). Multi-channel laser Doppler flowmetry (LDF) was used to measure MBF and electromagnetic flowmetry (EMF) for total flap blood flow. During normovolaemic conditions there was no significant difference between the two groups in central haemodynamic or respiratory data. After 15% blood loss, however, there was a significant decrease in mean arterial pressure and cardiac output in the halothane group while there was no significant change in the isoflurane group (P < 0.05). MBF in control skin, control muscle and flap muscle remained approximately 10−15% higher in the isoflurane than in the halothane group throughout the study. In the isoflurane group, MBF in flap skin was unchanged during normovolaemia and there was less than 10% decrease during hypovolaemia. In the halothane group hypovolaemia caused a significant decrease in MBF in flap skin: 27% decrease after 5% blood loss, 45% decrease after 10% blood loss and 49% decrease after 15% blood loss compared with 5%, 20% and 21%, respectively, in intact skin. We conclude that during normovolaemic conditions MBF was well maintained in musculocutaneous flaps in minipigs both with halothane and isoflurane anaesthesia; however, during mild to moderate hypovolemia MBF decreased markedly in flap skin with halothane anaesthesia while it remained unchanged with isoflurane