Effects of ropivacaine combined with morphine at 0.15 and 0.2 mg kg(-1) in bitches undergoing epidural anesthesia.

PURPOSE: To investigate cardiorespiratory effects and serum concentration of ropivacaine combined with morphine at different doses. METHODS: Sixteen healthy adult female dogs weighting 9.8 ± 4.1 kg were included in the study. Twenty minutes after being premedicated with acepromazine and midazolam, the animals were randomly assigned to receive an epidural injection according to each group: RM0.15 = ropivacaine + morphine (0.15 mg kg(-1)) and RM0.2 = ropivacaine + morphine (0.2 mg kg(-1)). Variables recorded consisted of: heart rate and cardiac rhythm, respiratory rate, oxyhemoglobin saturation, inspired oxygen fraction, end-tidal carbon dioxide tension, systolic, mean and diastolic arterial pressures, serum cortisol, plasma ropivacaine and morphine. RESULTS: SAP, MAP and DAP were significantly increased at TPR in RM0.15 but returned to normal values at the end of the procedure. Arterial pH was decreased in T30 and TESu in both groups and also returned to acceptable ranges at TR. Both PaO2 and PaCO2 were increased along the duration period of the epidural blockade (T30 and TESu) and returned to acceptable values at TR. Serum cortisol was lower at TB, T30 and TR when compared to TESu. CONCLUSION: The procedures were performed safely and minimal changes in cardiovascular and respiratory variables.

Effects of ropivacaine combined with morphine at 0.15 and 0.2 mg kg-1 in bitches undergoing epidural anesthesia

PURPOSE: To investigate cardiorespiratory effects and serum concentration of ropivacaine combined with morphine at different doses. METHODS: Sixteen healthy adult female dogs weighting 9.8±4.1 kg were included in the study. Twenty minutes after being premedicated with acepromazine and midazolam, the animals were randomly assigned to receive an epidural injection according to each group: RM0.15 = ropivacaine + morphine (0.15 mg kg-1) and RM0.2 = ropivacaine + morphine (0.2 mg kg-1). Variables recorded consisted of: heart rate and cardiac rhythm, respiratory rate, oxyhemoglobin saturation, inspired oxygen fraction, end-tidal carbon dioxide tension, systolic, mean and diastolic arterial pressures, serum cortisol, plasma ropivacaine and morphine. RESULTS: SAP, MAP and DAP were significantly increased at TPR in RM0.15 but returned to normal values at the end of the procedure. Arterial pH was decreased in T30 and TESu in both groups and also returned to acceptable ranges at TR. Both PaO2 and PaCO2 were increased along the duration period of the epidural blockade (T30 and TESu) and returned to acceptable values at TR. Serum cortisol was lower at TB, T30 and TR when compared to TESu. CONCLUSION: The procedures were performed safely and minimal changes in cardiovascular and respiratory variables. .

Bispectral index in calves anesthetized with xylazine, midazolam, ketamine, isoflurane and subjected to continuous rate infusion of lidocaine.

PURPOSE: To assess the bispectral index (BIS) and recovery in calves anesthetized with xylazine, midazolam, ketamine and isoflurane and subjected to CRI of lidocaine. METHODS: Xilazine was administered followed by ketamine and midazolam, orotracheal intubation and maintenance on isoflurane using mechanical ventilation. Lidocaine (2 mg kg(-1) bolus) or saline (0.9%) was administered i.v. followed by a CRI (100 µg kg(-1) minute(-1)) of lidocaine (L) or saline (C). Were recorded BIS, heart rate (HR), mean arterial pressure (MAP) and rectal temperature (RT) before administration of premedication (TB) and 15 minutes after (TX), before administering lidocaine (T0) and 20, 40, 60 and 80 minutes after the start of the CRI . Time do sternal recumbency (SRE) and standing (ST) and plasma lidocaine concentration also evaluated. RESULTS: In both treatments BIS decreased significantly at all times compared to TB. TX was higher than the subsequent times. HR decreased from baseline at all times and decreased from T40 in L compared to C. SRE was higher in L compared to C. CONCLUSIONS: Bispectral index values were consistent with the degree of hypnosis of the animals. Lidocaine did not potentiate isoflurane anesthesia assessed by BIS in unstimulated calves anesthetized with constant E´Iso. Lidocaine increased the time to sternal recumbency.

Bispectral index in calves anesthetized with xylazine, midazolam, ketamine, isoflurane and subjected to continuous rate infusion of lidocaine

PURPOSE: To assess the bispectral index (BIS) and recovery in calves anesthetized with xylazine, midazolam, ketamine and isoflurane and subjected to CRI of lidocaine. METHODS: Xilazine was administered followed by ketamine and midazolam, orotracheal intubation and maintenance on isoflurane using mechanical ventilation. Lidocaine (2 mg kg-1 bolus) or saline (0.9%) was administered IV followed by a CRI (100 µg kg-1 minute-1) of lidocaine (L) or saline (C). Were recorded BIS, heart rate (HR), mean arterial pressure (MAP) and rectal temperature (RT) before administration of premedication (TB) and 15 minutes after (TX), before administering lidocaine (T0) and 20, 40, 60 and 80 minutes after the start of the CRI . Time do sternal recumbency (SRE) and standing (ST) and plasma lidocaine concentration also evaluated. RESULTS: In both treatments BIS decreased significantly at all times compared to TB. TX was higher than the subsequent times. HR decreased from baseline at all times and decreased from T40 in L compared to C. SRE was higher in L compared to C. CONCLUSIONS: Bispectral index values were consistent with the degree of hypnosis of the animals. Lidocaine did not potentiate isoflurane anesthesia assessed by BIS in unstimulated calves anesthetized with constant E´Iso. Lidocaine increased the time to sternal recumbency. .

Effects of continuous rate infusion of butorphanol in isoflurane-anesthetized calves.

PURPOSE: To assess the hemodynamic changes and bispectral index (BIS) following administration of a continuous rate infusion (CRI) of butorphanol in isoflurane-anesthetized calves. METHODS: Eight calves weighing 110 ± 12 kg were included in the study. Anesthesia was induced with 5% isoflurane in O2 delivered via face mask and maintained with end-tidal concentration of 1.4%. IPPV was set to a peak inspiratory airway pressure of 15 cmH2O and respiratory rate of six breaths minute-1. Forty minutes after the start of anesthetic maintenance, 0.1 mg kg-1butorphanol was administered intravenously, followed by a CRI of 20 µg kg-1 minute-1. Hemodynamic variables and BIS were recorded before butorphanol administration (T0), and at 10, 20, 40 and 80 minutes following the CRI. Anesthesia was discontinued after the last recording and the calves were allowed to recover. The time to sternal recumbency (SRE) and standing (ST) were evaluated. RESULTS: There were no significant differences between the moments in all hemodynamic variables and BIS. The time to SRE and ST was 9 ± 5 and 14 ± 7 minutes, respectively. CONCLUSION: The continuous rate infusion did not produce clinically relevant changes in hemodynamic or bispectral index values compared to baseline in mechanically ventilated and unstimulated calves anesthetized at 1.4% isoflurane.

Effects of continuous rate infusion of butorphanol in isoflurane-anesthetized calves

PURPOSE: To assess the hemodynamic changes and bispectral index (BIS) following administration of a continuous rate infusion (CRI) of butorphanol in isoflurane-anesthetized calves. METHODS: Eight calves weighing 110 ± 12 kg were included in the study. Anesthesia was induced with 5% isoflurane in O2 delivered via face mask and maintained with end-tidal concentration of 1.4%. IPPV was set to a peak inspiratory airway pressure of 15 cmH2O and respiratory rate of six breaths minute-1. Forty minutes after the start of anesthetic maintenance, 0.1 mg kg-1butorphanol was administered intravenously, followed by a CRI of 20 µg kg-1 minute-1. Hemodynamic variables and BIS were recorded before butorphanol administration (T0), and at 10, 20, 40 and 80 minutes following the CRI. Anesthesia was discontinued after the last recording and the calves were allowed to recover. The time to sternal recumbency (SRE) and standing (ST) were evaluated. RESULTS: There were no significant differences between the moments in all hemodynamic variables and BIS. The time to SRE and ST was 9 ± 5 and 14 ± 7 minutes, respectively. CONCLUSION: The continuous rate infusion did not produce clinically relevant changes in hemodynamic or bispectral index values compared to baseline in mechanically ventilated and unstimulated calves anesthetized at 1.4% isoflurane. .

[Biodegradable systems containing prednisolone acetate for orbital administration]. / Sistemas biodegradáveis contendo acetato de prednisolona para administração orbitária.

PURPOSE: The present study aimed to evaluate an injectable extended-release formulation of prednisolone acetate (PA) for orbital administration. METHODS: Microspheres (MEs) of poly-e-caprolactone (PCL) containing PA were developed by the method of solvent evaporation. The MEs obtained were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), encapsulation efficiency and in vitro release profile. The in vivo release profile was evaluated in rabbits after periocular injection of an aqueous suspension of MEs. The local biocompatibility of the system was verified by histopathologic analysis of the deployment region. RESULTS: After MEs preparation, morphological analysis by SEM showed the feasibility of the employed method. The content of PA encapsulated was 43+/-7% and can be considered as satisfactory. The system characterization by DSC technique, in addition to confirm the system stability, did not indicate the existence of interaction between the drug and the polymer. The in vitro release study showed the prolonged-release features of the developed system. Preliminary in vivo study showed the absence of local toxicity and confirmed the prolonged release profile of PA from MEs, suggesting the viability of the developed system for the treatment of orbital inflammatory diseases. CONCLUSION: The results obtained in this work are relevant and accredit the system developed as a possible alternative to the treatment of inflammatory orbitopathy.