Vullo Cecilia, Gugliandolo Enrico, Biondi Vito, Biffarella Marco, Catone Giuseppe, Tambella Adolfo Maria
Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno D'Alcontres, 31, 98166 Messina, Italy.
Department of Veterinary Sciences, University of Messina, Polo SS. Annunziata, 98169 Messina, Italy.
Vet Sci. 2024 Mar 8;11(3):124. doi: 10.3390/vetsci11030124.
The aim of this study was to determine the most appropriate sedation protocol for a standing magnetic resonance imaging (MRI) examination in horses, comparing continuous rate infusions (CRIs) of detomidine and romifidine combined with a single bolus of morphine. Sixteen horses referred for standing low-field open-magnet MRI were randomly assigned to one of two sedation protocols. The horses were premedicated with 0.03 mg/kg of intramuscular acepromazine, and those animals belonging to Group D received an intravenous (IV) loading dose of detomidine (0.01 mg/kg) 30 min later, while those of Group R received romifidine (0.04 mg/kg). If the horses were inadequately sedated, an additional dose of IV detomidine (0.005 mg/kg) or romifidine (0.02 mg/kg) was administered, according to the animal's group. During the MRI, a single IV bolus of morphine (0.05 mg/kg) was administered, and according to which group it belonged to, the animal started the administration of detomidine (0.01 mg/kg/h) or romifidine (0.02 mg/kg/h). Heart rate (HR), respiratory rate (RR), rectal temperature (RT), depth of sedation, and degree of ataxia were evaluated every 10 min during MRI. Two horses belonging to Group D and four horses from Group R needed additional sedation before entering the MRI unit because they were unsatisfactorily sedated. No side effects were observed following morphine bolus administration. During the MRI procedure, five horses in Group R received an additional IV romifidine bolus (0.01 mg/kg) because the depth of sedation score was 1 and the ataxia score was 0. Any substantial differences were recorded between the two treatments in terms of HR, RR, and RT. In conclusion, at the doses used, a detomidine-morphine combination following a CRI of detomidine appears more suitable than a romifidine-morphine combination following a CRI of romifidine for maintaining an adequate depth of sedation and adequate immobility in horses undergoing standing MRI.
本研究的目的是确定马站立式磁共振成像（MRI）检查最合适的镇静方案，比较右美托咪定和罗米芬定持续速率输注（CRIs）联合单次推注吗啡的效果。16匹因站立式低场开放式磁共振成像检查前来就诊的马被随机分配到两种镇静方案之一。马匹先用0.03mg/kg的肌肉注射乙酰丙嗪进行预处理，30分钟后，D组动物静脉注射（IV）负荷剂量的右美托咪定（0.01mg/kg），而R组动物则接受罗米芬定（0.04mg/kg）。如果马匹镇静不足，则根据动物所属组别额外静脉注射右美托咪定（0.005mg/kg）或罗米芬定（0.02mg/kg）。在MRI检查期间，静脉注射单次推注吗啡（0.05mg/kg），并根据所属组别，动物开始输注右美托咪定（0.01mg/kg/h）或罗米芬定（0.02mg/kg/h）。在MRI检查期间，每10分钟评估一次心率（HR）、呼吸频率（RR）、直肠温度（RT）、镇静深度和共济失调程度。D组的两匹马和R组的四匹马在进入MRI检查室之前需要额外的镇静，因为它们的镇静效果不理想。推注吗啡后未观察到副作用。在MRI检查过程中，R组的五匹马接受了额外的静脉推注罗米芬定（0.01mg/kg），因为镇静深度评分为1，共济失调评分为0。两种治疗方法在HR、RR和RT方面均未记录到任何显著差异。总之，在所使用的剂量下，对于接受站立式MRI检查的马，右美托咪定持续速率输注后联合右美托咪定-吗啡组合似乎比罗米芬定持续速率输注后联合罗米芬定-吗啡组合更适合维持足够的镇静深度和足够的制动效果。
