首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
ObjectiveTo quantify the effects of medetomidine on the onset and duration of vecuronium-induced neuromuscular blockade in dogs.Study designRandomized, prospective clinical study.AnimalsTwenty-four, healthy, client-owned dogs of different breeds, aged between 6 months and 10 years and weighing between 5.0 and 40.0 kg undergoing elective surgery.MethodsDogs were randomly allocated to two groups. Pre-anaesthetic medication in group M+ was intramuscular acepromazine (ACP) 25 μg kg−1, morphine 0.5 mg kg−1 and medetomidine 5 μg kg−1. Group M− received ACP and morphine only, at the same dose rate. After induction with thiopental, anaesthesia was maintained with halothane in oxygen and nitrous oxide. End-tidal halothane concentration was maintained at 1.1%. Neuromuscular blockade was produced with intravenous vecuronium (50 μg kg−1) and monitored using a train of four stimulus applied at the ulnar nerve. The times taken for loss and reappearance of the four evoked responses (twitches [T]) were recorded. Normal and nonparametric data were analysed with an independent t-test and Mann-Whitney's U-test, respectively.ResultsThe fourth twitch (T4) disappeared at similar times in each group: 107 ± 19; [72–132] (mean ± SD; [range]) seconds in M+ and 98 ± 17 [72–120] seconds in M− dogs. The first twitch (T1) was lost at 116 ± 15; [96–132] seconds in group M+ and 109 ± 19; [72–132] seconds in M−. The fourth twitch returned significantly earlier in M+ dogs: 20.8 ± 3.8 [14–28] minutes compared with 23.8 ± 2.7 [20–27] minutes (p = 0.032). The duration of drug effect (T4 absent) was significantly shorter (p = 0.027) in M+ (18.9 ± 3.7 minutes) compared with M− dogs (22.2 ± 2.9 minutes). The recovery rate (interval between reappearance of T1 and T4) was significantly more rapid (p = 0.0003) in medetomidine recipients (3.0 ± 1.2 versus 5.2 ± 1.3 minutes).Conclusion and clinical relevance Medetomidine 5 μg kg−1 as pre-anaesthetic medication shortened the duration of effect of vecuronium in halothane-anaesthetized dogs and accelerated recovery, but did not affect the onset time. These changes are of limited clinical significance.  相似文献   

2.
ObjectiveTo determine the impact of epidural phentolamine on the duration of anaesthesia following epidural injection of lidocaine–epinephrine.Study designBlinded randomized experimental study.AnimalsA group of 12 adult ewes weighing 25.7 ± 2.3 kg and aged 8–9 months.MethodsAll sheep were administered epidural lidocaine (approximately 4 mg kg–1) and epinephrine (5 μg mL–1). Of these, six sheep were randomized into three epidural treatments, separated by 1 week, administered 30 minutes after lidocaine–epinephrine: SAL: normal saline, PHE1: phentolamine (1 mg) and PHE2: phentolamine (2 mg). The other six sheep were administered only epidural lidocaine–epinephrine: treatment LIDEP. Each injection was corrected to 5 mL using 0.9% saline. Noxious stimuli were pinpricks with a hypodermic needle and skin pinch with haemostatic forceps to determine the onset and duration of sensory and motor block. Heart rate, noninvasive mean arterial pressure (MAP), respiratory rate and rectal temperature were recorded.ResultsThe onset times were not different among treatments. Duration of sensory block was significantly shorter in SAL (57.5 ± 6.2 minutes), PHE1 (60.7 ± 9.0 minutes) and PHE2 (62.0 ± 6.7 minutes) than in LIDEP (81.7 ± 13.4 minutes) (p < 0.05). Duration of motor blockade was significantly shorter in PHE1 (59.4 ± 5.4 minutes) and PHE2 (54.3 ± 4.0 minutes) than in SAL (84.8 ± 7.0 minutes) and LIDEP (91.5 ± 18.2 minutes) (p < 0.01). MAP in PHE2 was decreased at 10 minutes after administration of phentolamine (p < 0.05).Conclusion and clinical relevanceEpidural administration of 5 mL normal saline after epidural injection of lidocaine–epinephrine reduced the duration of sensory but not motor block in sheep. Epidural administration of phentolamine diluted to the final volume of 5 mL diminished both the duration of sensory and motor block in sheep administered epidural lidocaine–epinephrine.  相似文献   

3.
Objective  To compare the analgesic and motor-blocking effects of epidurally administered levobupivacaine and bupivacaine in the conscious dog.
Study design  Prospective, randomized, cross-over study.
Animals  Six adult female Beagle dogs.
Methods  Each animal received three doses of levobupivacaine or bupivacaine (0.5, 1.0 and 1.5 mg kg−1; concentrations 0.25%, 0.50%, and 0.75%, respectively) in a total volume of 0.2 mL kg−1 by means of a chronically implanted epidural catheter. Onset, duration (through pinch response in the sacral, lumbar and toe areas) and degree of analgesia and motor-blocking status was determined with a scoring system and at regular intervals over 8.5 hours before (baseline) and after drug administration.
Results  Epidurally administered levobupivacaine and bupivacaine had a similar dose-dependent analgesic action with no significant differences in onset (range: 5–8 minutes), duration (bupivacaine: 42 ± 28, 135 ± 68 and 265 ± 68 minutes, and levobupivacaine: 28 ± 33, 79 ± 55 and 292 ± 133 minutes; 0.25%, 0.50%, and 0.75%, respectively) or maximum degree of analgesia. However, levobupivacaine tended to produce a shorter duration of motor block than bupivacaine and the difference in the motor to nociceptive blockade times was significant at the highest dose.
Conclusion  Epidural levobupivacaine produced an analgesic action similar to that of bupivacaine.
Clinical relevance  Epidural levobupivacaine is suitable for clinical use in dogs, mostly at the highest dose if a high degree of analgesia is required.  相似文献   

4.
ObjectiveTo evaluate the cardiovascular effects of a preload of hydroxyethylstarch 6% (HES), preceding an epidural administration of ropivacaine 0.75% in isoflurane anaesthetized dogs.AnimalsSix female, neutered Beagle dogs (mean 13.3 ± SD 1.0 kg; 3.6 ± 0.1 years).Study designRandomized experimental cross-over study (washout of 1 month).MethodsAnaesthesia was induced with propofol and maintained with isoflurane in oxygen/air. All dogs were anaesthetized twice to receive either treatment HESR (continuous rate infusion [CRI] of 7 mL kg?1 HES started 30 minutes [T-30] prior to epidural administration of ropivacaine 0.75% 1.65 mg kg?1 at T0) or treatment R (no HES preload and similar dose and timing of epidural ropivacaine administration). Baseline measurements were obtained at T-5. Heart rate (HR), mean (MAP), diastolic (DAP) and systolic (SAP) invasive arterial pressures, cardiac output (Lithium dilution and pulse contour analysis) and derived parameters were recorded every 5 minutes for 60 minutes. Statistical analysis was performed on five dogs, due to the death of one dog.ResultsClinically relevant decreases in MAP (<60 mmHg) were observed for 20 and 40 minutes following epidural administration in treatments HESR and R respectively. Significant decreases in MAP and DAP were present after treatment HESR for up to 20 minutes following epidural administration. No significant within-treatment and overall differences were observed for other cardiovascular parameters. A transient unilateral Horner's syndrome occurred in two dogs (one in each treatment). One dog died after severe hypotension, associated with epidural anaesthesia.Conclusions and clinical relevanceA CRI of 7 mL kg?1 HES administered over 30 minutes before epidural treatment did not prevent hypotension induced by epidural ropivacaine 0.75%. Epidural administration of ropivacaine 0.75% in isoflurane anaesthetized dogs was associated with a high incidence of adverse effects in this study.  相似文献   

5.
ObjectiveTo examine the spread of solution in the epidural space of sternally recumbent dogs.Study designProspective experimental trial.AnimalsTen healthy adult Beagle dogs weighing 7.6 ± 1.1 kg.MethodsDogs were anaesthetized with total intravenous propofol infusion, and placed in sternal recumbency. A volume of 0.2 mL kg?1 contrast medium (CM) containing 1% new methylene blue (MB) dye was administered into the lumbosacral epidural space. Left to right lateral radiographs using a horizontal beam were taken every 5 minutes for 45 minutes. The perpendicular height (PH) between floor of the epidural canal of the highest vertebra and that of lumbosacral spinal canal was measured on radiographs. The angle of slope from the injection point toward the highest vertebral floor was measured. Immediately after taking the last radiographic image, dogs were euthanized and a laminectomy was performed from the cervical to lumbar vertebrae for visual evaluation of MB spread. The spread of CM and of MB as counted in number of stained vertebra were compared, and each of these data sets were further compared to PH and angle, using linear regression analyses.ResultsThe PH and angle were (mean ± SD) 3.8 ± 0.8 cm and 14.8 ± 2.8° respectively. The most cranial spread of CM was at 12.7 ± 5.7 (range: C6–L3) vertebrae, and at 14.0 ± 5.4 (range: C6–L2) vertebrae for MB staining. There were no significant correlations between PH and spread of CM (R2 = 0.08) or MB (R2 = 0.13), between angle and spread of CM (R2 = 0.05) or MB (R2 = 0.02), respectively. CM and MB demonstrated proportional relationship (R2 = 0.82, p < 0.001).ConclusionsNo significant inhibitory effect of upward slope on cranial epidural spread of the solution was observed. Other factors may have greater effect on epidural spread in sternally recumbent dogs.  相似文献   

6.
ObjectiveTo investigate the clinical efficacy of four analgesia protocols in dogs undergoing tibial tuberosity advancement (TTA).Study designProspective, randomized, blinded study.AnimalsThirty-two client owned dogs undergoing TTA-surgery.MethodsDogs (n= 8 per treatment) received an oral placebo (PM and PRM) or tepoxalin (10 mg kg?1) tablet (TM and TRM) once daily for 1 week before surgery. Epidural methadone (0.1 mg kg?1) (PM and TM) or the epidural combination methadone (0.1 mg kg?1)/ropivacaine 0.75% (1.65 mg kg?1) (PRM and TRM) was administered after induction of anaesthesia. Intra-operative fentanyl requirements (2 μg kg?1 IV) and end-tidal isoflurane concentration after 60 minutes of anaesthesia (Fe′ISO60) were recorded. Post-operative analgesia was evaluated hourly from 1 to 8 and at 20 hours post-extubation with a visual analogue scale (VAS) and the University of Melbourne Pain Scale (UMPS). If VAS > 50 and/or UMPS > 10, rescue methadone (0.1 mg kg?1) was administered IV. Analgesic duration (time from epidural until post-operative rescue analgesia) and time to standing were recorded. Normally distributed variables were analysed with an F-test (α = 0.05) or t-test for pairwise inter-treatment comparisons (Bonferonni adjusted α = 0.0083). Non-normally distributed data were analysed with the Kruskall–Wallis test (α = 0.05 or Bonferonni adjusted α = 0.005 for inter-treatment comparison of post-operative pain scores).ResultsMore intra-operative analgesia interventions were required in PM [2 (0–11)] [median (range)] and TM [2 (1–2)] compared to PRM (0) and TRM (0). Fe′ISO60 was significantly lower in (PRM + TRM) compared to (PM + TM). Analgesic duration was shorter in PM (459 ± 276 minutes) (mean ± SD) and TM (318 ± 152 minutes) compared to TRM (853 ± 288 minutes), but not to PRM (554 ± 234 minutes). Times to standing were longer in the ropivacaine treatments compared to TM.Conclusions and clinical relevanceInclusion of epidural ropivacaine resulted in reduction of Fe′ISO60, avoidance of intra-operative fentanyl administration, a longer duration of post-operative analgesia (in TRM) and a delay in time to standing compared to TM.  相似文献   

7.

Objective

To evaluate the efficacy, in terms of the amount of rescue analgesia required, and the clinical usefulness of epidural injection of morphine with bupivacaine or levobupivacaine for elective pelvic limb surgery in dogs during a 24-hour perioperative period.

Study design

Prospective, blinded, randomized clinical study.

Animals

A group of 26 dogs weighing 31.7 ± 14.2 (mean ± standard deviation) kg and aged 54 ± 36 months.

Methods

All dogs were premedicated with methadone intravenously (0.2 mg kg–1) and anaesthesia induced with diazepam (0.2 mg kg–1) and propofol intravenously to effect. After induction of anaesthesia, dogs randomly received a lumbosacral epidural injection of morphine 0.1 mg kg–1 with either levobupivacaine 0.5% (1 mg kg–1; group LevoBM) or bupivacaine 0.5% (1 mg kg–1; group BM). Cardiovascular, respiratory and temperature values were recorded during the intra- and postoperative period. A visual analogue scale, subjective pain scale, sedation scale and the short form of the Glasgow pain scale were assessed every 6 hours after epidural injection during 24 hours. The ability to stand and walk, neurological deficits and other side effects were assessed at the same time points. The amount of rescue analgesia (sufentanil intraoperatively and methadone postoperatively) was recorded.

Results

No statistically significant differences were found between groups for any of the recorded data, with the exception of the incidence of spontaneous urination and postoperative rescue analgesia requirement. In group LevoBM four dogs spontaneously urinated at recovery while none of the dogs in group BM did (p = 0.03) and seven dogs of group LevoBM required postoperative rescue analgesia versus none of the dogs in the BM group (p = 0.005).

Conclusions

and clinical relevance Epidural LevoBM is a suitable alternative to BM in healthy dogs during elective pelvic limb surgery. Epidural BM produced more urinary retention but better pain control compared to the same concentration and dose of LevoBM in dogs.  相似文献   

8.
ObjectiveTo evaluate the use of ultrasound for identifying the site for needle puncture and to determine the depth to the epidural space in obese dogs.Study designProspective study in dogs undergoing elective orthopedic surgery.AnimalsA group of seven obese Labrador male dogs aged 6.93 ± 2.56 years and weighing 46.5 ± 4.1 kg (mean ± standard deviation).MethodsThe anesthetic protocol for these dogs included epidural anesthesia. With the dogs anesthetized and positioned in sternal recumbency with the pelvic limbs flexed forward, ultrasound imaging was used to locate the lumbosacral intervertebral space. Intersection of dorsal and transverse lines about the probe identified the point of needle insertion. A 17 gauge, 8.9 cm Tuohy needle was inserted perpendicularly through the skin and advanced to the lumbosacral intervertebral space. The number of puncture attempts was recorded and needle depth was compared with skin to ligamentum flavum distance.ResultsEpidural injection was performed in all dogs at the first attempt of needle insertion. The distance from skin to epidural space was 5.95 ± 0.62 cm measured by ultrasound and 5.89 ± 0.64 cm measured with the Tuohy needle. These measurements were not different (p = 0.26). A highly significant correlation coefficient of 0.966 between measurement techniques was obtained (p < 0.001).Conclusions and clinical relevanceUltrasound imaging identified the point of needle insertion for lumbosacral epidural injection in seven obese dogs. The results indicate that ultrasound can be used to locate the lumbosacral intervertebral space and identify an appropriate point for needle insertion to perform epidural injection.  相似文献   

9.
Objective The aim of this study was to characterize the onset and duration of action of the aminosteroid muscle relaxant rocuronium in dogs under clinical conditions. Study design Prospective single dose trial. Animals Twenty‐three dogs aged between 6 months and 12 years, weighing between 5.5 and 61.5 kg admitted to the University of Liverpool Small Animal Hospital between January and March 2000, and undergoing elective surgical procedures under general anaesthesia. Materials and methods Following induction of general anaesthesia, neuromuscular function was evaluated using train‐of‐four (TOF) stimulation. An initial dose of 0.4 mg kg?1 rocuronium was administered intravenously (IV) and neuromuscular blockade was monitored by visually assessing the number of responses (twitches) to TOF stimulation (train‐of‐four count: TOFC). Incremental doses of 0.16 mg kg?1 rocuronium were administered as indicated, when at least two twitches of the TOFC had returned. Results Rocuronium (0.4 mg kg?1) abolished all responses to TOF stimulation in all dogs. The mean time to onset of neuromuscular blockade (complete abolition of all twitches) was 98 ± 52 seconds. Neuromuscular blockade (absence of all twitches to return of all four) lasted 32.3 ± 8.2 minutes. Incremental doses of 0.16 mg kg?1 had a mean duration of action of 20.8 ± 4.9 minutes and up to seven increments were shown to be noncumulative. The effects of rocuronium were readily antagonized with neostigmine and atropine. Small transient increases in arterial blood pressure, which occurred in three dogs after the administration of rocuronium, were the only cardiovascular side‐effects observed. Conclusions Rocuronium is an effective nondepolarizing neuromuscular blocking agent in the dog, with a rapid onset of neuromuscular block after intravenous administration and an intermediate duration of action. Clinical relevance Rocuronium produced a neuromuscular block with similar characteristics to those obtained with vecuronium, thus apparently offering little advantage over vecuronium. However, its availability in aqueous solution and a longer shelf‐life increases convenience.  相似文献   

10.
Buprenorphine is an effective analgesic when administered epidurally to humans. The purpose of this study was to compare epidural buprenorphine (B; n = 10) with epidural morphine (M; n = 10) for post‐operative analgesia in dogs undergoing cranial cruciate ligament repair. All dogs were premedicated with acepromazine (0.1 mg kg?1 IM), induced with propofol (4–6 mg kg?1 IV) and maintained with halothane in oxygen. Dogs were randomly assigned to receive B (0.004 mg kg?1) or M (0.1 mg kg?1) in the lumbosacral epidural space in a total volume of 0.2 mL kg?1. End‐tidal halothane and CO2 and temperature were recorded every 15 minutes until extubation (t = 0). A numerical rating pain score (SPS) was recorded at t = 0, 1, 2, 4, 6, 10 and 24 hours by a blinded observer. Dogs received rescue morphine (1.0 mg kg?1 IM) if indicated by SPS and the time of rescue analgesic administration was recorded. Observable side‐effects such as urinary retention, sedation or pruritus were recorded. Data were analyzed with repeated measures anova . Mean ± SD body weight (kg) and age (yrs) for B dogs was 34.2 ± 10.8 and 5.5 ± 2.8; for M dogs these values were 36.6 ± 13.5 and 5.9 ± 3.3. Mean ± SD SPS for B dogs at t = 0, 1, 2, 4, 6, 10 and 24 hours were 1.2 ± 0.75, 3.2 ± 2.0, 4.5 ± 4.3, 4.6 ± 3.4, 4.7 ± 3.0, 5.0 ± 4.9 and 5.1 ± 3.5. For M dogs these values were 1.7 ± 0.5, 2.6 ± 2.0, 3.7 ± 0.75, 4.2 ± 2.2, 4.1 ± 3.0, 3.1 ± 2.1 and 3.9 ± 1.9. There were no significant differences between B and M with respect to SPS, times or frequency of rescue morphine administration, end‐tidal halothane and CO2, or esophageal temperature. Fifty per cent of dogs in both groups required rescue morphine. Buprenorphine is as effective as morphine for epidural analgesia in healthy dogs undergoing hindlimb orthopedic surgery.  相似文献   

11.
Alpha2 agonists have a significant role in epidural anaesthetic techniques. However, there are few reports regarding epidural administration of these drugs especially in small animals ( Greene et al. 1995; Keegan et al. 1995; Vesal et al. 1996 ). This study compared the haemodynamic effects of xylazine and medetomidine after epidural injection in dogs. Six dogs (four females and two males) weighing 27.5 ± 3.39 kg, aged 5.6 ± 1.42 years were studied on two separate occasions one month apart. Dogs were sedated with 0.5 mg kg?1 diazepam IM and 0.1 mg kg?1 acepromazine IM. After 20 minutes, a lumbosacral epidural injection of 0.25 mg kg?1 xylazine was administered (group X). One month later, following the same sedation, 15 µg kg?1 medetomidine was administered epidurally (group M). Haemodynamic variables (ECG and indirect blood pressure (Doppler)), respiratory rate and rectal temperature were recorded before (baseline) and then every 5 minutes after the epidural injection, up to 60 minutes. Differences between groups were compared by a paired t‐test. Within group changes were compared to basal values by anova . A p‐value of < 0.05 was considered statistically significant. Both groups showed significant reductions in heart rate (106.3 ± 7.7 beats minute?1 baseline versus 67.7 ± 7.6 (group M); 91 ± 3.8 baseline versus 52.3 ± 9 (group X)) and mean arterial blood pressure (113.1 ± 12.3 mm Hg baseline versus 87 ± 11 (group M); 118 ± 7 baseline versus 91 ± 14 (group X)). There were no differences between groups in these variables. After epidural injection, first degree atrioventricular block was recorded significantly more often in group X (50% against 33%) but second degree block was significantly more frequent in group M (66% against 33%). Also 50% of dogs in group X and 66% in group M showed sinus arrest. Respiratory rate decreased significantly in both groups following the epidural injection (20.66 ± 0.66 minute?1 baseline versus 16.33 ± 4.77 (group M); 37.66 ± 0.56 baseline versus 16.33 ± 1.81 group X), but no differences between groups were observed. Rectal temperature decreased significantly in group X (38.16 ± 0.21) with respect to the basal measurement (39.30 ± 0.14 °C). In group M, there was no significant reduction in temperature, however, no statistical difference in rectal temperature was found between groups. This study shows that 0.25 mg kg?1 xylazine and 15 µg kg?1 medetomidine produce similar, significant cardiovascular and respiratory changes following lumbosacral epidural administration in dogs.  相似文献   

12.
ObjectiveTo compare the effects of sevoflurane, propofol and alfaxalone on the neuromuscular blockade induced by a single intravenous bolus of rocuronium in dogs.Study designA randomized, prospective, crossover experimental study.AnimalsA total of eight adult Beagle dogs (four female, four male), weighing 8.9–15.3 kg and aged 5–7 years.MethodsThe dogs were anesthetized three times with 1.25× minimum alveolar concentration of sevoflurane (SEVO treatment) and 1.25× minimum infusion rate of propofol (PROP treatment) or alfaxalone (ALFX treatment) at intervals of ≥14 days. Neuromuscular function was monitored with train-of-four (TOF) stimulation of the peroneal nerve by acceleromyography. After recording the control TOF ratio (TOFRC), a single bolus dose of rocuronium (1 mg kg–1) was administered intravenously. The times from rocuronium administration to achieving TOF count 0 (onset time), from achieving TOF count 0 to the reappearance of TOF count 4 (clinical blockade period), from 25% to 75% of TOFRC (recovery index) and from achieving TOF count 0 to TOF ratio/TOFRC >0.9 (total neuromuscular blockade duration) were recorded.ResultsThe onset time and recovery index did not differ among the treatments. The median clinical blockade period was longer in the SEVO treatment [27.3 (26.0–30.3) minutes] than in PROP [16.6 (15.4–18.0) minutes; p = 0.002] and ALFX [22.4 (18.6–23.1) minutes; p = 0.017] treatments; and longer in the ALFX treatment than in the PROP treatment (p = 0.020). The mean total neuromuscular blockade duration was longer in the SEVO treatment (43.7 ± 9.9 minutes) than in PROP (25.1 ± 2.7 minutes; p < 0.001) and ALFX (32.5 ± 8.4 minutes; p = 0.036) treatments.Conclusions and clinical relevanceCompared with alfaxalone and propofol, sevoflurane prolonged rocuronium-induced neuromuscular blockade by a significantly greater extent in dogs.  相似文献   

13.
A central eyeball position is often required during sedation or anaesthesia to facilitate examination of the eye. However, use of neuromuscular blockade to produce a central eye position may result in depressed ventilation. This study evaluated the eyeball position, muscle relaxation and changes in ventilation during general anaesthesia after the IV administration of 0.1 mg kg?1 rocuronium. With client consent, 12 dogs of different breeds, body mass 27.2 ± 11.8 kg, aged 5.6 ± 2.8 years (mean ± SD) were anaesthetized for ocular examination. Pre‐anaesthetic medication was 0.01 mg kg?1 medetomidine and 0.2 mg kg?1 butorphanol IV. Anaesthesia was induced with propofol to effect and maintained with 10 mg kg?1 hour?1 propofol by infusion. The dogs were placed in left lateral recumbency, their trachea intubated and connected to a circle breathing system (Fi O2 = 1.0). All dogs breathed spontaneously. The superficial peroneal nerve of the right hind leg was stimulated every 15 seconds with a train‐of‐four (TOF) stimulation pattern and neuromuscular function was assessed with an acceleromyograph (TOF‐Guard). Adequacy of ventilation was measured with the Ventrak 1550. After 10 minutes of anaesthesia to allow stabilisation of baseline values, 0.1 mg kg?1 rocuronium was administered IV. Minute volume (Vm ), tidal volume (Vt ), respiratory rate (RR), Pe ′CO2 and maximal depression of T1 and TOF ratio were measured. Data were analysed using a paired t‐test. The changes in the eyeball position were recorded. A total of 100 ± 33 seconds after the injection of rocuronium, T1 was maximally depressed to 62 ± 21% and the TOF ratio to 42 ± 18% of baseline values. Both variables returned to baseline after 366 ± 132 seconds (T1) and 478 ± 111 seconds (TOF). There was no significant reduction in Vm (2.32 ± 1.1 L minute?1), Vt (124.1 ± 69.3 mL) and RR (10 ± 3.8 breaths minute?1) and no increase in Pe ′CO2 (6.5 ± 2.1 kPa (48.8 ± 16.1 mm Hg)) throughout the procedure. The eyeball rotated to a central position 35 ± 7 seconds after rocuronium IV and remained there for a minimum of 20 ± 7 minutes in all dogs. We conclude that rocuronium at a dose of 0.1 mg kg?1 can be administered to dogs IV with minimal changes in ventilatory variables. The eyeball is fixed in a central position for at least 20 minutes, which greatly facilitates clinical examination.  相似文献   

14.
ObjectiveTo compare the cardiovascular effects of four epidural treatments in isoflurane anaesthetised dogs.Study designProspective, randomized. experimental study.AnimalsSix female, neutered Beagle dogs (13.3 ± 1.0 kg), aged 3.6 ± 0.1 years.MethodsAnaesthesia was induced with propofol (8.3 ± 1.1 mg kg?1) and maintained with isoflurane in a mixture of oxygen and air [inspiratory fraction of oxygen (FiO2) = 40%], using intermittent positive pressure ventilation. Using a cross-over model, NaCl 0.9% (P); methadone 1% 0.1 mg kg?1 (M); ropivacaine 0.75% 1.65 mg kg?1 (R) or methadone 1% 0.1 mg kg?1 + ropivacaine 0.75% 1.65 mg kg?1 (RM) in equal volumes (0.23 mL kg?1) using NaCl 0.9%, was administered epidurally at the level of the lumbosacral space. Treatment P was administered to five dogs only. Cardiovascular and respiratory variables, blood gases, and oesophageal temperature were recorded at T-15 and for 60 minutes after epidural injection (T0).ResultsMean overall heart rate (HR in beats minute?1) was significantly lower after treatment M (119 ± 16) (p = 0.0019), R (110 ± 18) (p < 0.0001) and RM (109 ± 13) (p < 0.0001), compared to treatment P (135 ± 21). Additionally, a significant difference in HR between treatments RM and M was found (p = 0.04). After both ropivacaine treatments, systemic arterial pressures (sAP) were significantly lower compared to other treatments. No significant overall differences between treatments were present for central venous pressure, cardiac output, stroke volume, systemic vascular resistance, oxygen delivery and arterial oxygen content (CaO2). Heart rate and sAP significantly increased after treatment P and M compared to baseline (T-15). With all treatments significant reductions from baseline were observed in oesophageal temperature, packed cell volume and CaO2. A transient unilateral Horner’s syndrome occurred in one dog after treatment R.Conclusions and clinical relevanceClinically important low sAPs were observed after the ropivacaine epidural treatments in isoflurane anaesthetised dogs. Systemic arterial pressures were clinically acceptable when using epidural methadone.  相似文献   

15.
Objective —The purpose of this study was to determine the hemodynamic effects of epidural ketamine administered during isoflurane anesthesia in dogs. Study Design —Prospective, single-dose trial. Animals —Six healthy dogs (five males, one female) weighing 25.3 ± 3.88 kg. Methods —Once anesthesia was induced, dogs were maintained at 1.5 times the predetermined, individual minimum alveolar concentration (MAC) of isoflurane. Dogs were instrumented and allowed to stabilize for 30 minutes before baseline measurements were recorded. Injection of 2 mg/kg of ketamine in 1 mL saline/4.5 kg body weight was then performed at the lumbosacral epidural space. Hemodynamic data were recorded at 5, 10, 15, 20, 30, 45, 60, and 75 minutes after epidural ketamine injection. Statistical analysis included an analysis of variance (ANOVA) for repeated measures over time. All data were compared with baseline values. A P < .05 was considered significant. Results —Baseline values ±standard error of the mean (X ± SEM) for heart rate, mean arterial pressure, mean pulmonary artery pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, stroke index, systemic vascular resistance, pulmonary vascular resistance, and rate-pressure product were 108 ± 6 beats/min, 85 ± 10 mm Hg, 10 ± 2 mm Hg, 3 ± 1 mm Hg, 5 ± 2 mm Hg, 2.3 ± 0.3 L/min/m2, 21.4 ± 1.9 mL/beat/m2, 3386 ± 350 dynes/sec/cm5, 240 ± 37 dynes/sec/cm5, and 12376 ± 1988 beats/min±mm Hg. No significant differences were detected from baseline values at any time after ketamine injection. Conclusions —The epidural injection of 2 mg/kg of ketamine is associated with minimal hemodynamic effects during isoflurane anesthesia. Clinical Relevance —These results suggest that if epidural ketamine is used for analgesia in dogs, it will induce minimal changes in cardiovascular function.  相似文献   

16.
ObjectiveTo compare the duration of action of vecuronium in diabetic dogs with a control group.Study designProspective clinical study.AnimalsForty client-owned diabetic (n = 20) and non-diabetic dogs.MethodsDogs were considered free from other concurrent disease based on clinical examination and laboratory data. After pre-anaesthetic medication with acepromazine and methadone, anaesthesia was induced with intravenous (IV) propofol and maintained with isoflurane-nitrous oxide in oxygen. Neuromuscular blockade (NMB) was achieved with vecuronium, 0.1 mg kg?1 IV and its effects recorded by palpation (pelvic limb digital extension) and electromyography (m. tibialis cranialis) of responses (twitches; T) to repeated train-of-four (TOF) nerve stimulation. Time to onset of NMB was the period between vecuronium injection and loss of fourth twitch (T4) in the TOF pattern recorded by EMG and palpation. Duration of NMB was defined as the time from drug administration to return of T1 by palpation (T1tactile) and EMG (T1EMG). Times to return of T2-4 were also recorded. Time from induction of anaesthesia to vecuronium injection was recorded. Heart rate, non-invasive mean arterial pressure, body temperature, end-tidal isoflurane and end-tidal CO2 concentrations were recorded at onset of NMB and when T1EMG returned. Loss and return of palpable and EMG responses for diabetic and non-diabetic dogs were compared using t-tests and Mann Whitney U-tests.ResultsThere were significant (p < 0.05) differences between diabetic and non-diabetic dogs for the return of all four palpable and EMG responses. Times (mean ± SD) for return of T1tactile were 13.2 ± 3.5 and 16.9 ± 4.2 minutes in diabetic and non-diabetic dogs respectively. There were no differences between diabetic and non-diabetic dogs in the time to onset of vecuronium with EMG or tactile monitoring.Conclusions and clinical relevanceThe duration of action of vecuronium was shorter in diabetic dogs as indicated by both tactile and EMG monitoring.  相似文献   

17.
ObjectiveTo compare n. facialis-m. nasolabialis (nF-mNL) and n. ulnar-mm. carpi flexorii (nU-mCF) sensitivity to vecuronium during halothane or isoflurane anaesthesia.Study designRandomized, prospective, experimental study.AnimalsForty-four client-owned dogs (19 male, 25 female) undergoing surgery; mean age: 5.0 years; mean body mass: 24.7 kg.MethodsThirty minutes after acepromazine (0.05 mg kg?1) and morphine (0.5 mg kg?1), anaesthesia was induced with intravenous (IV) thiopental and maintained with either halothane (n = 22) or isoflurane (randomly allocated) in oxygen. The lungs were mechanically ventilated and end-tidal inhaled anaesthetic (Fe’IAA) maintained at 1.2 × MAC values. Neuromuscular transmission at nF-uNL and nU-mCF was monitored using the train of four count. Vecuronium (50 μg kg?1 IV) was injected (t = 0) after 15 trains, 50-60 minutes after inhalational anaesthesia began, when Fe’IAA had been constant for >15 minutes. Times of the disappearance (-) and reappearance (+) of the fourth (T4) and first twitch (T1) were recorded allowing the calculation of: latent (t = 0 to T4-) and manifest onset times (t = 0 to T1-) duration of blockade (T1- to T1+) and drug effect (T4- to T4+) and recovery time (T1+-T4+). Student’s paired t-test was used to compare simultaneous responses at nF-uNL and nU-mCF. An unpaired t-test was used to compare anaesthetic effects.ResultsLatent and manifest onset times were significantly (p < 0.05) briefer, blockade and drug effects were significantly longer and recovery from blockade were significantly slower in the nF-mNL unit in both halothane and isoflurane recipients. Profound block duration and drug action were significantly longer and recovery from blockade were significantly slower in halothane recipients at both nerve-muscle units.Conclusion and clinical relevanceThe nF-mNL was more sensitive than nU-mCF to vecuronium, particularly in halothane-anaesthetized dogs.  相似文献   

18.
ObjectiveTo evaluate the effectiveness of paravertebral lumbar plexus block combined with parasacral sciatic block to anesthetize one hind limb in awake dogs.Study designRandomized, controlled, blinded experimental study.AnimalsEight healthy mongrel dogs weighing 12.4 ± 4.5 kg and aged 7 ± 2.33 years.MethodsAfter sedation with medetomidine, dogs received B1: bupivacaine 0.25%, 0.2 mL kg?1, B2: bupivacaine 0.5%, 0.2 mL kg?1, B3: bupivacaine 0.25% 0.4 mL kg?1, P1: NaCl 0.2 mL kg?1, P2: NaCl 0.4 mL kg?1. The lumbosacral plexus was blocked through a paravertebral block of the fourth, fifth and sixth lumbar nerves combined with a parasacral block. The relevant nerves were located using a nerve stimulator and injections of each treatment were administered. Degree and durations of sensory blockade were determined through the response to a Halsted clamp pressure on the skin innervated by the saphenous/femoral and lateral cutaneous femoral nerves (lumbar dermatomes) and by the peroneal and tibial nerves. The degree and duration of motor blockade was assessed evaluating the ability to walk normally and proprioception.ResultsP1 and P2 treatments did not show any grade of sensory or motor blockade. The B2 treatment produced a higher degree of sensory blockade compared to B1 and B3 for both lumbar and sciatic dermatomes. There was no significant difference in the degree of sensory blockade comparing B1 to B3. The B2 treatment had greater motor blockade compared to B1 and B3. The duration of sensory and motor blockade was longer in B2 compared to B1 and B3.Conclusion and clinical relevanceWhen the nerve stimulator is used to perform the lumbosacral plexus block, the concentration of the bupivacaine has a more important role than the volume to produce a more solid and longer block.  相似文献   

19.
ObjectiveTo compare the recovery after anaesthesia with isoflurane, sevoflurane and desflurane in dogs undergoing magnetic resonance imaging (MRI) of the brain.Study designProspective, randomized clinical trial.AnimalsThirty‐eight dogs weighing 23.7 ± 12.6 kg.MethodsFollowing pre‐medication with meperidine, 3 mg kg?1 administered intramuscularly, anaesthesia was induced intravenously with propofol (mean dose 4.26 ± 1.3 mg kg?1), the trachea was intubated, and an inhalational anaesthetic agent was administered in oxygen. The dogs were randomly allocated to one of three groups: group I (n = 13) received isoflurane, group S (n = 12) received sevoflurane and group D (n = 13) received desflurane. Parameters recorded included cardiopulmonary data, body temperature, end‐tidal anaesthetic concentration, duration of anaesthesia, and recovery times and quality. Qualitative data were compared using chi‐squared and Fisher's exact tests and quantitative data with anova and Kruskal–Wallis test. Post‐hoc comparisons for quantitative data were undertaken with the Mann–Whitney U‐test.ResultsThe duration of anaesthesia [mean and standard deviation (SD)] in group I was: 105.3 (27.48) minutes, group S: 120.67 (19.4) minutes, and group D: 113.69 (26.68) minutes (p = 0.32). Times to extubation [group I: 8 minutes, (interquartile range 6–9.5), group S: 7 minutes (IQR 5–7), group D: 5 minutes (IQR 3.5–7), p = 0.017] and to sternal recumbency [group I: 11 minutes (IQR 9.5–13.5), group S: 9.5 minutes (IQR 7.25–11.75), group D: 7 minutes (range 3.5–11.5), p = 0.048] were significantly different, as were times to standing. One dog, following sevoflurane, had an unacceptable quality of recovery, but most other recoveries were calm, with no significant difference between groups.Conclusions and clinical relevanceAll three agents appeared suitable for use. Dogs’ tracheas were extubated and the dogs recovered to sternal recumbency most rapidly after desflurane. This may be advantageous for animals with some neurological diseases and for day case procedures.  相似文献   

20.
Volumes used in lumbosacral epidural injections for anesthesia have remained unchanged since the 1960s. The goals of this cross‐sectional observational study were to characterize the three‐dimensional spread of a lumbosacral epidural injection, as well as confirm that the commonly used volume of 0.2 ml/kg injected into the lumbosacral epidural space reaches the thoracolumbar (TL) junction in the majority (≥80%) of dogs. Ten clinically normal, adult, nonpregnant, mixed‐breed dogs were obtained within five minutes of euthanasia and 0.2 ml/kg of radiopaque contrast medium was injected into the lumbosacral epidural space. A computed tomography scan of the TL spine was performed immediately following the injection. Migration of contrast reached the TL junction in 8 of 10 (80%) dogs. Contrast was well visualized in all epidural planes with contrast travelling predominantly in the dorsal epidural space in 7 of 10 (70%) dogs. There was no significant difference in the weight of dogs where the epidural injectate reached the TL junction and those where it did not (P = 0.16), or in the weight of dogs where the cranial‐most point of the contrast column was in the dorsal versus the ventral epidural space (P = 0.32). This preliminary study supports the use of computed tomography to characterize injectate distribution in the canine thoracolumbar epidural space and provides evidence that a 0.2‐ml/kg volume is likely to reache the TL junction in most dogs. Further studies are needed in live dogs to determine if variables affecting human epidural injectate doses have similar effects in the dog.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号