ABSTRACT
BACKGROUND: A suitable pharmacological substitute for the well-established surgical delay technique for random skin flaps to increase viability has been elusive. OBJECTIVE: To evaluate the effects of nitroglycerin and botulinum toxin type A on random flap survival in a rat model. METHODS: The present controlled experimental study was performed in the four groups of rats. One week after intervention in each group, the flap was raised and kept in situ, and flap necrosis was evaluated through follow-up. Group 1 received intradermal botulinum toxin type A (BTX-A) and topical nitroglycerin 2%; group 2 received BTX-A and topical Vaseline (Unilever, USA); group 3 received topical nitroglycerin and intradermal normal saline; and group 4 received topical Vaseline and intradermal normal saline. RESULTS: BTX-A reduced the area of necrosis compared with control (24% versus 56% respectively; P<0.001). Nitroglycerin application was associated with a trend toward improved flap viability (42% versus 56%; P=0.059). The combination of topical nitroglycerin and BTX-A, compared with Vaseline and BTX-A, was associated with decreased flap necrosis (16.1% versus 24%, respectively), although it was not statistically significant (P=0.45). CONCLUSIONS: BTX-A was effective in reducing distal flap necrosis. The effect of BTX-A was significantly more pronounced than nitroglycerin ointment.
HISTORIQUE: Il n'existe aucun substitut pharmacologique convenable pour remplacer la technique d'autonomisation bien établie visant à accroître la survie des lambeaux cutanés. OBJECTIF: Évaluer les effets de la nitroglycérine et de la toxine botulique de type A (BTX-A) sur la survie de lambeaux sans dissection pédiculaire dans un modèle de rat. MÉTHODOLOGIE: Les chercheurs ont réalisé la présente étude expérimentale contrôlée auprès de quatre groupes de rats. Dans chaque groupe, une semaine après l'intervention, ils ont prélevé le lambeau et l'ont conservé in situ, puis ont évalué la nécrose du lambeau au suivi. Le groupe 1 a reçu de la BTX-A par voie intradermique et de la nitroglycérine topique 2 %. Le groupe 2 a reçu de la BTX-A et de la Vaseline topique (Unilever, États- Unis). Le groupe 3 a reçu de la nitroglycérine topique et un soluté physiologique par voie intradermique. Enfin, le groupe 4 a reçu de la Vaseline topique et un soluté physiologique par voie intradermique. RÉSULTATS: La BTX-A réduisait l'aire de la nécrose par rapport à celle des sujets témoins (24 % au lieu de 56 %, respectivement; P<0,001). L'application de nitroglycérine favorisait une meilleure viabilité du lambeau (42 % par rapport à 56 %; P=0,059). Par rapport à la Vaseline et à la BTX-A, la combinaison de nitroglycérine topique et de BTX-A s'associait à une diminution de la nécrose du lambeau (16,1 % au lieu de 24 %), même si ce n'était pas statistiquement significatif (P=0,45). CONCLUSIONS: La BTX-A a réussi à réduire la nécrose du lambeau distal. Elle avait beaucoup plus d'effet que l'onguent de nitroglycérine.
ABSTRACT
OBJECTIVE: Anesthetic agents are often combined to enhance their therapeutic effects while minimizing adverse events. The aim of this study was to evaluate the effects of two different sedation regimens of ketamine and propofol combination via infusion on perioperative variables in patients who underwent plastic and reconstructive surgery. METHODS: This randomized double-blind clinical trial was done on 80 patients who were randomized to two groups; group 1 (n = 40) received a 2:1 mixture of 9 mg/ml propofol and 4.5 mg/ml ketamine, and group 2 (n = 40) received a 4:1 mixture of 9 mg/ml propofol and 2.25 mg/ml ketamine. After premedication and before local anesthetic injection, the infusion of mixtures was adjusted to attain the Ramsay sedation scores of 5 in both groups. We recorded induction time, sedation efficacy, cardiovascular and respiratory events, recovery time, and incidence of adverse events during and after the procedure. RESULTS: The mean of volume infusion of mixtures in the beginning of the procedure was higher in group 2 (3.2 ± 1. 2 ml) than in group 1 (2.4 ± 0.8 ml) (p < 0.001). The induction time for sedation was 2.8 ± 0.8 min and 2.6 ± 0.4 min in group 1 and group 2, respectively (p = 0. 92). The number of oversedated patients was greater in group 2 compared to group 1 but not statistically significant (p = 0. 80). The sedation efficacy was similar between the two groups. The hemodynamic changes during the procedure were greater in group 2 compared to group 1 (p = 0. 001). The recovery time was not significantly different between the two groups (p = 0.43). The mean pain score in the recovery room was lower in group 1 than group 2 (1.2 ± 0.8 vs 2.8 ± 1.8, p = 0. 01). Moreover, 4 (10 %) patients in group 1 and 10 (25 %) patients in group 2 needed opioid administration (p = 0. 02). Other postoperative adverse events were similar between the two groups. CONCLUSION: We recommend the use of a 2:1 combination of propofol-ketamine, because it reduced the rescue propofol requirement and consequently produced lower cardiovascular and respiratory depression effects and also less postoperative pain.
