Thiamylal-Sparing Effect of Midazolam for Canine Endotracheal Intubation A Clinical Study of 118 Dogs

One hundred eighteen dogs were studied at three veterinary teaching hospitals after the administration of midazolam (0.1 mg/kg, intravenously [IV]) or a placebo. Midazolam and placebo treatments were randomized and blinded to the investigators. The dose of thiamylal required for tracheal intubation 3 to 5 minutes after midazolam or placebo was calculated. The dose of thiamylal at the three hospitals was 10.6,9.8, and 10.1 mg/kg IV after midazolam, and 12.1,11.2, and 11.6 mg/kg IV after placebo. Pooled data from the three hospitals yielded a significant (p < .001) decrease in mean IV thiamylal dose after midazolam (10.2 mg/kg) compared with placebo (11.6 mg/kg). Overall, there was a 12% decrease in the dose of thiamylal required for tracheal intubation after midazolam compared to that after the placebo. The thiamylal dose was significantly (p < .001) decreased after midazolam compared with placebo for dogs weighing more than 15 kg but not for dogs weighing less than 15 kg.     

Retroversion of the Epiglottis as a Complication of Endotracheal Intubation in the Horse A Pilot Study

As part of a study of possible causes of postoperative pulmonary complications of general anesthesia in the horse, lateral cervical radiographs were taken after endotracheal intubation in nine randomly selected horses. The epiglottis was found to be retroverted in three. Subsequently, the effects of epiglottic retroversion during anesthesia on postoperative laryngeal function were investigated experimentally in three horses by fluoroscopy. No untoward sequelae were observed. Prophylaxis and potential adverse effects of this previously unreported complication of endotracheal intubation in the horse are discussed.     

Thoracoscopic Subphrenic Pericardectomy Using Double‐Lumen Endobronchial Intubation for Alternating One‐Lung Ventilation

Objective— To report the technique, complications, and effectiveness of thoracoscopic subphrenic pericardectomy (SPP) using double‐lumen endobronchial intubation for alternating 1‐lung (OLV) in healthy dogs. Study Design— Prospective cohort study. Animals— Mature purpose‐bred dogs (n=7). Methods— Bronchoscope‐assisted placement of a left‐sided double‐lumen endobronchial tube, immediately before surgery, allowed intraoperative alternation of ventilation between lung fields. A camera portal was established in a subxyphoid location. Two instrument portals were established at the 4th–6th intercostal spaces on the right and left sides. A vessel‐sealing device was used to create the subphrenic pericardectomy. After termination of the procedure, dogs were humanely euthanatized under anesthesia and necropsy performed. In each dog, the extent of pericardectomy and any complications were evaluated. Results— Technical difficulties with tube placement occurred in 4 dogs, but alternating OLV was achieved in all dogs and SPP completed successfully. Median surgical time was 87.5 minutes (range, 80–105 minutes). At necropsy, 0.5–2 cm of pericardial tissue remained ventral to the intact phrenic nerve in 6 dogs; in 1 dog, the phrenic nerve was transected on the left side only. Conclusions— Thoracoscopic subphrenic pericardectomy is a technically feasible procedure in healthy dogs. Double‐lumen endobronchial intubation allowed alternating OLV without intraoperative bronchoscopically guided tube manipulation in all but 1 dog. Clinical Relevance— Thoracoscopic subphrenic pericardectomy could potentially be used for management of conditions where relief of pericardial constriction or access to intrapericardial structures is desired.     

灌胃染镉对大鼠体内某些酶的影响及镉的器官分布

30只成年雌性SD大鼠，等分为5组，Ⅰ至Ⅳ组灌胃馀服分别含0、0.2、1.0、2.0mg镉（Cd）的氯化镉溶液1mL／只，每日1次，持续10d；Ⅴ组灌镉剂量与Ⅳ组相同，持续时间为30d。结果发现，染镉组（Ⅱ－Ⅳ组）：血浆丙氨酸氨基转移酶（ALT）和精氨酸酶（ARG）活力明显升高（P＜0.05），但ALT活力升高剂量－效在系不规律；肝匀浆ALT活力明显下降（P＜0.05或P＜0.01）；全血谷胱甘肽过氧化物酶（GSH－Px）活力显著下降（P＜0.05），肝匀浆中GSH－Px的活力也下降；心、肝、肾中Cd的含量无意产加，蓄积量与灌服剂量呈正相关（r值分别为0.9384、0.9687和0.9379）。Ⅳ组和Ⅴ组比较，随时间延长，心、肝、肾中Cd蓄积量均明显增加，且肾较肝增加更显著，结论认为，灌胃染镉对大鼠的生长有障碍作用，镉可以明显地抑制SH－Px的活力，降低机体组织的抗氧化能力，引起肝等实质细胞的损伤；血浆ARG的活力可以作为哺乳动物急性镉暴露的一个辅助性监测指标；由于损伤性泄漏和直接的抑制同时存在，以血浆中ALT的活力来评价镉对实质器官的损害应十分慎重。