Efficacy of tramadol for postoperative pain management in dogs: systematic review and meta-analysis

ObjectiveTo evaluate the evidence of analgesic efficacy of tramadol for the management of postoperative pain and the presence of associated adverse events in dogs.Databases usedA comprehensive search using PubMed/MEDLINE, LILACS, Google Scholar and CAB databases with no restrictions on language and following a prespecified protocol was performed from June 2019 to July 2020. Included were randomized controlled trials (RCTs) performed in dogs that had undergone general anesthesia for any type of surgery. Two authors independently classified the studies, extracted data and assessed their risk of bias using Cochrane’s tool. RevMan and GRADE methods were used to rate the certainty of evidence (CoE).ConclusionsOverall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26–0.85; I² = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20–1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16–3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00–0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95% CI: 0.66–18.08; I² = 43%) and COX inhibitors (low CoE; RR: 2.27; 95% CI: 0.68–7.60; I² = 45%). Compared with multimodal therapy, tramadol administration may make minimal to no difference in the requirement for rescue analgesia (low CoE; RR: 1.12; 95% CI: 0.48–2.60; I² = 0%). Adverse events were inconsistently reported and the CoE was very low. The overall CoE of the analgesic efficacy of tramadol for postoperative pain management in dogs was low or very low, and the main reasons for downgrading the evidence were risk of bias and imprecision.     

Comparison of intraperitoneal ropivacaine and bupivacaine for postoperative analgesia in dogs undergoing ovariohysterectomy

Objective

To compare postoperative analgesia following either intraperitoneal (IP) ropivacaine or bupivacaine in dogs undergoing ovariohysterectomy (OVH) in the scope of multimodal analgesia.

The effect of neuraxial morphine on postoperative pain in dogs after extrahepatic portosystemic shunt attenuation

ObjectiveTo investigate the analgesic effect of epidural morphine after surgical extrahepatic portosystemic shunt (EHPSS) attenuation.Study designRandomized clinical trial.AnimalsA total of 20 dogs with a congenital EHPSS.MethodsDogs were randomly allocated to be given either a single epidural dose of 0.2 mg kg^–1 preservative-free morphine (group M) or not (group C) before surgery. All dogs were administered 0.3 mg kg^–1 methadone intravenously (IV) as preanaesthetic medication. Pain scores were determined every 2 hours for the first 24 hours postoperatively using the short-form Glasgow Composite Measure Pain Scale (GCMPS-SF). Dogs with a GCMPS-SF pain score >4/20 or >5/24 received 0.1 mg kg^–1 methadone IV as rescue analgesia and were reassessed 30 minutes later. If more than three doses of methadone were administered in a 2 hour period, alternative pain relief was provided and a treatment failure recorded. The GCMPS-SF pain scores and number of rescue analgesia injections were analysed over 24 hours. The last observation carried forward method was applied in case of treatment failure. Food consumption and time to first urination were recorded. Data were analysed using a Mann–Whitney U test and presented as median (minimum–maximum range), with significance set at p < 0.05.ResultsGroup M showed lower GCMPS-SF pain scores [15 (11–41) versus 31 (11–86); p = 0.023] and lower postoperative methadone requirements [0 (0–0.2) versus 0.25 (0–0.5) mg kg^–1; p = 0.029] than group C. There were three treatment failures in group C only. Food consumption and time to first urination did not differ between groups.Conclusions and clinical relevanceEpidural morphine reduced the requirement for postoperative analgesia in this study population.     

Yamamoto New Scalp Acupuncture for postoperative pain management in cats undergoing ovariohysterectomy

Objective

To evaluate the analgesic efficacy of Yamamoto New Scalp Acupuncture (YNSA) as an adjuvant for postoperative pain management in cats.

Anesthetic and analgesic techniques used for dogs undergoing ovariohysterectomies in general practice in the United States

ObjectiveTo acquire information about anesthesia and analgesia protocols used by United States (US) veterinarians in primary care practices when performing routine ovariohysterectomy in dogs.Study designCross-sectional survey.PopulationPrimary care veterinarians in the US.MethodsAn online anonymous survey, originally created in New Zealand, was modified with permission and made available to Veterinary Information Network (VIN) members. The survey asked questions about performing ovariohysterectomy in healthy adolescent dogs in the categories of preanesthetic evaluation, premedication and induction protocols, maintenance protocols and monitoring equipment, and postoperative analgesic and sedation protocols and pain assessments.ResultsA total of 1213 US veterinarians completed the survey. Respondents (n; %) reported performing preoperative laboratory tests [packed cell volume (135; 11%), complete blood cell count (889; 73%) and biochemistry panels (1057; 87%)] and preanesthetic examinations on the morning of surgery (1083; 90%). The most commonly administered drugs for premedication were acepromazine (512; 42%), hydromorphone (475; 39%) or butorphanol (463; 38%), with propofol (637; 67%) for induction of anesthesia and isoflurane (882; 73%) for maintenance of anesthesia. Most veterinarians reported placing intravenous catheters (945; 78%), administering electrolyte solutions (747; 67%) and providing heat support (1160; 96%). Perioperative and postoperative analgesia included local anesthetics (545; 45%), opioids (844; 70%) and non-steroidal anti-inflammatory drugs (NSAIDs) (953; 79%); NSAIDs were dispensed for home use (985; 81%). Dogs were most frequently discharged on the day of surgery (1068; 88%) and the owners were contacted (914; 75%) for follow-up within 1–2 days.Conclusions and clinical relevanceAnesthetic management for routine ovariohysterectomy in dogs varies among US veterinary VIN members. Information from this study is useful for all veterinarians for comparison with their practice management and for teachers of veterinary anesthesia to continue to emphasize options for analgesia.     

A comparison of epidural buprenorphine with epidural morphine for postoperative analgesia following stifle surgery in dogs

Objective To compare the efficacy of epidural buprenorphine with epidural morphine for post‐operative pain relief in dogs undergoing cranial cruciate ligament rupture repair. Study design A randomized, double blind clinical trial. Animals Twenty client‐owned dogs with cranial cruciate ligament rupture. Methods Dogs were randomly assigned to receive either epidural buprenorphine (4 µg kg^?1) or epidural morphine (0.1 mg kg^?1) in a total volume of 0.2 mL kg^?1. Epidural injections were performed immediately after induction of anesthesia. End‐tidal halothane and CO₂ were recorded every 15 minutes from the time of epidural administration of drug to extubation. A numerical rating pain score system was used by a blinded observer to evaluate analgesia beginning at extubation and continuing at specific intervals for 24 hours after surgery. Heart rate, respiratory rate, and blood pressure were recorded noninvasively at the same times. If pain score indicated moderate discomfort, rescue morphine at 1.0 mg kg^?1 was administered intramuscularly. Results There were no significant differences between groups with respect to pain score, heart rate, respiratory rate, indirect blood pressure, end‐tidal halothane or end‐tidal CO₂ at any time point. Fifty percent of dogs in the buprenorphine group and 50% of dogs in the morphine group required rescue analgesic medication. Time of systemic rescue morphine administration did not differ significantly between the two groups. There were no clinically observable side‐effects from epidural administration of either drug in any of the dogs of this study. Conclusions Epidural buprenorphine is as effective as epidural morphine for the relief of postoperative hindlimb orthopedic pain in dogs. Clinical relevance Buprenorphine appears to be an effective opioid for epidural use in healthy dogs. Buprenorphine may offer certain advantages over morphine for epidural use, such as lower abuse potential and, in some clinics, reduced cost and less wastage of drug.     

A comparison of preoperative tramadol and morphine for the control of early postoperative pain in canine ovariohysterectomy

Objective To compare morphine with tramadol for the management of early postoperative pain following ovariohysterectomy after pyometra in dogs. Study design Prospective randomized blinded clinical trial. Animals Thirty female dogs, 2–14 years old. Methods Animals were randomly divided into two equal groups. Group 1 received 0.2 mg kg^?1 of morphine IV and group 2 received 2 mg kg^?1 of tramadol IV after the induction of anesthesia. The dogs were premedicated with acepromazine, and anesthesia was induced with intravenous midazolam and ketamine. Isoflurane was used for the maintenance of anesthesia. The variables measured were: analgesia; sedation; cardiac and respiratory rates; arterial blood pressure; end‐tidal isoflurane and carbon dioxide (Pe ′CO₂); oxyhemoglobin saturation (SpO₂); plasma catecholamines; serum cortisol and glucose concentrations; pH and blood gases. The animals were monitored for 6 hours after the administration of the analgesic agent. Results There were no differences between the two groups with regard to analgesia, sedation, SpO₂, pH and blood gases, cardiovascular variables, glucose, catecholamine and cortisol concentrations. Forty minutes postopioid administration, the end‐tidal isoflurane concentration was significantly lower in the morphine‐treated group as compared to the tramadol group. At 30 minutes following opioid injection, Pe ′CO₂ was significantly higher in the morphine group than in the tramadol group. Two dogs in the tramadol group and one in the morphine group were given morphine postoperatively because of increasing pain scores. Conclusion and clinical relevance Morphine and tramadol, administered preemptively can be used safely in dogs to control early pain after ovariohysterectomy without significant adverse effects.     

Effects of tramadol alone,in combination with meloxicam or dipyrone,on postoperative pain and the analgesic requirement in dogs undergoing unilateral mastectomy with or without ovariohysterectomy

ObjectiveTo compare the effects of tramadol alone, or in combination with dipyrone or meloxicam, on postoperative pain and analgesia requirement after unilateral mastectomy with or without ovariohysterectomy in dogs.Study designProspective, randomized, clinical study.AnimalsTwenty seven bitches undergoing unilateral mastectomy with or without ovariohysterectomy.MethodsAnesthesia was induced with propofol and maintained with isoflurane and a constant rate infusion of morphine. Before the end of surgery, dogs were randomly assigned to receive intravenous tramadol alone (3 mg kg^?1, group T), combined with dipyrone (30 mg kg^?1, group TD) or meloxicam (0.2 mg kg^?1, group TM). Dogs received additional doses of tramadol (groups T and TM) or tramadol with dipyrone (group TD) at 8 and 16 hours after extubation. Postoperative pain was assessed by a blinded observer before anesthesia (baseline) and at 1, 2, 3, 4, 6, 8, 12, 16 and 24 hours after extubation using a visual analog scale (VAS) and a modified Glasgow scale. Rescue analgesia (morphine, 0.5 mg kg^?1) was administered if the Glasgow pain score was >3.5.ResultsThere were no significant differences among groups in pain scores evaluated by the VAS or the Glasgow scale. In groups T, TD and TM, pain scores were significantly higher than at baseline for 6, 8 and 2 hours, respectively. Rescue analgesia was administered to 3/9, 2/9 and 1/9 dogs in groups T, TD and TM, respectively (p > 0.05) [Correction added on 15 August 2013, after first online publication: ‘T, TM and TD’ was changed to ‘T, TD and TM’.].Conclusions and clinical relevanceUnder the conditions of this study, tramadol alone or in combination with dypyrone or meloxicam provided effective analgesia for 24 hours in most dogs after unilateral mastectomy with or without ovariohysterectomy. Further evaluation of combination therapies is needed in larger groups of dogs.     

Clinical evaluation of the efficacy and safety of a constant rate infusion of dexmedetomidine for postoperative pain management in dogs

ObjectiveTo compare postoperative analgesia provided by a constant rate infusion (CRI) of dexmedetomidine (DMED) to that of a well-established positive control [morphine (MOR)] in critically ill dogs. The sedative, cardiorespiratory effects and clinical safety of a 24-hour DMED CRI were also evaluated.Study designProspective, randomised, blinded, positive-controlled parallel-group clinical study.AnimalsForty hospitalised, client-owned dogs requiring post-operative pain management after invasive surgery.MethodsAfter surgery, a loading dose of either DMED (25 μg m^?2) or MOR (2500 μg m^?2) followed by a 24-hour CRI of DMED (25 μg m^?2 hour^?1) or MOR (2500 μg m^?2 hour^?1) was administered. Pain was measured using the Short Form of the Glasgow Composite Measure Pain Scale, sedation and physiological variables were scored at regular intervals. Animals considered to be painful received rescue analgesia and were allocated to a post-rescue protocol; animals which were unresponsive to rescue analgesia were removed from the study. Data were analysed with anova, two-sample t-tests or Chi-square tests. Time to intervention was analysed with Kaplan–Meier methodology.ResultsForty dogs were enrolled. Twenty dogs (9 DMED and 11 MOR) did not require rescue analgesia. Eleven DMED and eight MOR dogs were allocated to the post-rescue protocol and seven of these removed from the study. Significant differences in pain scores between groups were not observed during the first 12 hours, however, DMED dogs were less (p = 0.009) painful during the last 12 hours. Sedation score over the entire 24-hour study was not significantly different between groups.Conclusion / Clinical RelevanceDexmedetomidine CRI was equally effective as MOR CRI at providing postoperative analgesia and no clinically significant adverse reactions were noted. This study shows the potential of DMED to contribute to a balanced postoperative analgesia regimen in dogs.     

Effect of gonadectomy on pain assessment in dogs undergoing orthopaedic stifle surgery

ObjectiveTo compare pain perception between gonadectomized and intact dogs.Study designBlinded, prospective, cohort study.AnimalsA group of 74 client-owned dogs.MethodsDogs were divided into four groups: group 1—female/neutered (F/N), group 2—female/intact (F/I), group 3—male/neutered (M/N) and group 4—male/intact (M/I). Premedication consisted of intramuscularly administered acepromazine (0.05 mg kg⁻¹) and morphine (0.2 mg kg⁻¹), and subcutaneously administered carprofen (4 mg kg⁻¹). Anaesthesia was induced with propofol (1 mg kg⁻¹ intravenously and supplementary doses to effect) and maintained with isoflurane in 100% oxygen. Intraoperative analgesia was achieved with fentanyl infusion (0.1 μg kg⁻¹ minute⁻¹). Pain assessments [using the University of Melbourne Pain Scale (UMPS) and an algometer at the incision site (IS), parallel to the incision site (NIS), and on the contralateral healthy limb] were performed preoperatively, and at 1, 2, 4, 6, 9 and 20 hours after extubation. The time-standardised area under the curve (AUCst) for measurements was calculated and compared by performing a one-way multivariate analysis of variance (manova). Statistical significance was set at p < 0.05.ResultsPostoperatively, F/N exhibited higher pain than F/I, with estimated marginal means (95% confidence intervals) AUCstIS_Group1 909 (672–1146) versus AUCstIS_Group2 1385 (1094–1675) (p = 0.014), AUCstNIS_Group1 1122 (823–1420) versus AUCstNIS_Group2 1668 (1302–2033) (p = 0.024) and AUCstUMPS_Group1 5.30 (4.58–6.02) versus AUCstUMPS_Group2 4.1 (3.2–5.0) (p = 0.041). Similarly, M/N showed higher pain than M/I with AUCstIS_Group3 686 (384–987) versus AUCstIS_Group4 1107 (871–1345) (p = 0.031) and AUCstNIS_Group3 856 (476–1235) versus AUCstNIS_Group4 1407 (1109–1706) (p = 0.026), and AUCstUMPS_Group3 6.0 (5.1–6.9) versus AUCstUMPS_Group4 4.4 (3.7–5.2) (p = 0.008).Conclusions and clinical relevance:Gonadectomy affects pain sensitivity in dogs undergoing stifle surgery. Neutering status should be taken into consideration when planning individualized anaesthetic/analgesic protocols.     

Timely adjuvant chemotherapy improves outcome in dogs with non-metastatic splenic hemangiosarcoma undergoing splenectomy

Timely delivery of adjuvant chemotherapy has been shown to be advantageous in many human cancers and canine osteosarcoma. Adjuvant chemotherapy has been shown to improve outcome for canine splenic hemangiosarcoma. The aim of this retrospective study was to investigate whether timely adjuvant chemotherapy administration resulted in better outcome in dogs with non-metastatic splenic hemangiosarcoma undergoing splenectomy. Medical records were searched for dogs with non-metastatic, splenic hemangiosarcoma that received splenectomy and adjuvant chemotherapy. The number of days from surgery to the first chemotherapy dose (StoC) was evaluated to identify the cut-off value associated with the best survival advantage. StoC and other possible prognostic factors were tested for influence on time to metastasis (TTM) and overall survival (OS). Seventy dogs were included. Median StoC was 20 days (range: 4–70). The time interval associated with the greatest survival benefit was 21 days. Median TTM and OS of dogs with StoC ≤ 21 days were significantly longer than those with StoC >21 days (TTM: 163 vs. 118 days, p = .001; OS: 238 vs. 146 days, p < .001). On multivariable analysis, StoC >21 days was the only variable significantly associated with increased risk of tumour progression (HR 2.1, p = .010) and death (HR 2.3; p = .008). Starting adjuvant chemotherapy within 21 days of surgery may be associated with a survival benefit in dogs with non-metastatic splenic hemangiosarcoma, possibly due to the early targeting of newly recruited metastatic cells after surgery.     

Assessment of the effects of adjunctive gabapentin on postoperative pain after intervertebral disc surgery in dogs

ObjectiveTo assess the effect of adjunctive gabapentin (GBP) on pain after thoracolumbar intervertebral disc surgery in dogs.Study designProspective, randomized, controlled, clinical, ‘blinded’ trial.AnimalsSixty-three client owned dogs undergoing hemilaminectomyMethodsDogs were assigned to two treatment groups. The GBP group received gabapentin 10 mg kg^?1 orally every 12 hours starting before anaesthesia; the placebo (P) group received empty gelatin capsules. Background analgesia was initiated with intravenous levomethadone 0.6 mg kg^?1 (as the combination ‘L-Polamivet) at anaesthesia induction, followed by a fentanyl patch and levomethadone 0.2 mg kg^?1 subcutaneously every 8 hours for 24 hours. Pain was assessed by the short form of the Glasgow Composite Measure Pain Score (CMPS-SF) without the gait category, and by a Visual Analogue Scale (VAS). Serum GBP concentrations and cortisol concentrations were measured. Statistical analyses utilized chi square test, Kolmogorov-Smirnov test, two-way analysis of variances for repeated measurements, Wilcoxon test and Friedmann test as relevant. Correlations were tested by Spearman's and Pearson's correlation coefficient. p< 0.05 was considered significant.ResultsMedian CMPS-SF was lower in group GBP than in group P on days 0.5, 1, 4 and 5. However, CMPS-SF and VAS were not significantly different between groups. Both pain scores decreased significantly over time. Cortisol concentrations were not significantly different between groups. Minimum serum concentrations of GBP fell below the detection limit of 1 μg mL^?1 in 6 of 29 and 7 of 28 dogs at 24 and 72 hours, respectively.Conclusions and clinical relevance10 mg kg^?1 GBP orally twice a day did not result in a detectable reduction in pain behaviour compared to background opioid analgesia alone, although a trend to lower pain levels (p < 0.1) was present. Further studies are needed to determine if this is related to effective background analgesia or an ineffective dose of GBP.     

Evaluation of prescribing practices for gabapentin as an analgesic among veterinary professionals

ObjectiveTo describe the prescribing practices for gabapentin as an analgesic within the veterinary community.Study designAnonymous online voluntary survey.PopulationA total of 718 veterinarians within the United States and Canada, including general practitioners and diplomates of the American Colleges of Veterinary Anesthesia and Analgesia, Emergency and Critical Care, Surgery and Internal Medicine.MethodsAn anonymous online survey was used to gather information about individual prescribing practices for gabapentin including frequency of use, reasons for prescribing and procedures for authorizing refill requests. Questions specific to gabapentin covered mechanisms of action, perceptions of efficacy and the potential for abuse in people. Dunn’s test for multiple comparisons and pairwise Mann–Whitney U test were used to evaluate relationships between veterinary specialty and survey responses.ResultsA total of 718 veterinarians responded to the survey, 528 (73.5%) answered all questions of the survey to completion. Frequency of prescribing was high with 365/529 (69.0%) of respondents prescribing gabapentin as an analgesic on a daily or weekly basis. Surgeons and general practitioners used gabapentin significantly more frequently than other groups, with surgeons more likely to prescribe gabapentin for postoperative pain. The most common reason [254/517 (49.1%)] survey respondents prescribed gabapentin as an analgesic was because administration of a non-steroidal anti-inflammatory medication was contraindicated for that animal. The majority of survey respondents [362/527 (68.7%)] considered the abuse potential of gabapentin to be low in people.Conclusions and clinical relevanceVeterinary prescribing practices for gabapentin closely mirrored that of human physicians, with gabapentin being prescribed frequently and for uses largely unrelated to its labeled indication. The perception of the potential for abuse of gabapentin is low within the veterinary community.     

Assessment of postoperative pain after unilateral mastectomy using two different surgical techniques in dogs

Background

There are few studies reporting pain and postoperative analgesia associated with mastectomy in dogs. The aim of this study was to evaluate postoperative pain after unilateral mastectomy using two different surgical techniques in the dog.

Findings

Twenty female dogs were assigned (n=10/group) to undergo unilateral mastectomy using either the combination of sharp and blunt dissection (SBD) or the modified SBD (mSBD) technique, in which the mammary chain is separated from the abdominal wall entirely by blunt (hand and finger) dissection except for a small area cranial to the first gland, in a prospective, randomized, clinical trial. All dogs were premedicated with intramuscular acepromazine (0.05 mg/kg) and morphine (0.3 mg/kg). Anesthesia was induced with intravenous ketamine (5 mg/kg) and diazepam (0.25 mg/kg), and maintained with isoflurane. Subcutaneous meloxicam (0.2 mg/kg) was administered before surgery. Postoperative pain was evaluated according to the University of Melbourne pain scale (UMPS) by an observer who was blinded to the surgical technique.. Rescue analgesia was provided by the administration of intramuscular morphine (0.5 mg/kg) if pain scores were >14 according to the UMPS. Data were analyzed using t-tests and ANOVA (P>0.05). There were no significant differences between the groups for age, weight, extubation time, and duration of surgery and anesthesia (P>0.05). There were no significant differences for postoperative pain scores between groups. Rescue analgesia was required in one dog in each group.

Conclusions

The two surgical techniques produced similar surgical times, incidence of perioperative complications and postoperative pain. Multimodal analgesia is recommended for treatment of postoperative pain in dogs undergoing unilateral mastectomy.     

Evaluation of adjuvant carboplatin chemotherapy in the management of surgically excised anal sac apocrine gland adenocarcinoma in dogs

There is no widely accepted standard of care for canine anal sac apocrine gland adenocarcinoma (ASAGAC). Surgery alone is inadequate in many cases, but the benefit of adjuvant chemotherapy is not well established. The primary objective of this retrospective study was to evaluate the role of carboplatin chemotherapy in the post‐operative management of ASAGAC. Seventy‐four dogs with naturally occurring ASAGAC underwent surgery. Forty‐four dogs received adjuvant carboplatin and 30 did not. Median overall survival (OS) was 703 days. Median time to progression (TTP) was 384 days. Only primary tumour size and lymph node metastasis at diagnosis significantly impacted the outcome. Differences in OS and TTP, between the dogs that received adjuvant carboplatin and those that did not, failed to reach statistical significance. Treatment of progressive disease, whilst not limited to chemotherapy, significantly prolonged the survival. This study shows that adjuvant carboplatin chemotherapy is well tolerated and may have a role in the management of dogs with ASAGAC.     

Analgesic management of an eight-year-old Springer Spaniel after amputation of a thoracic limb

Analgesic agents were administered perioperatively to an eight-year-old Springer Spaniel undergoing amputation of its right thoracic limb. The amputation was carried out due to a painful, infiltrative and poorly differentiated sarcoma involving the nerves of the brachial plexus. A combination of pre-emptive and multimodal perioperative analgesic strategies was used; including intravenous (IV) infusions of fentanyl, morphine, lidocaine and ketamine.     

Effects of postoperative ketamine infusion on pain control and feeding behaviour in bitches undergoing mastectomy

OBJECTIVES: To determine if ketamine administered to bitches at the end of a mastectomy, followed by a six-hour constant rate infusion (CRI), improved postoperative opioid analgesia and feeding behaviour. METHODS: The bitches were randomised into three groups: the placebo group received 0.09 ml/kg isotonic saline intravenously followed by a six-hour CRI of 0.5 ml/kg/hour, the low-dose ketamine received 150 microg/kg ketamine intravenously followed by a six-hour CRI of 2 microg/kg/minute and the high-dose ketamine group received 700 microg/kg ketamine intravenously followed by a six-hour CRI of 10 microg/kg/minute. Any additional opioids given were recorded at the time of extubation and at intervals after extubation. Food intake was evaluated eight (T8) and 20 (T20) hours after extubation by measuring the per cent coverage of basal energy requirements (BER). RESULTS: No significant difference was observed for opioid requirements between the three groups. The mean percentages of BER coverage did not differ significantly at T8 but the difference between the high-dose and low-dose ketamine groups (P=0.014), and the high-dose ketamine and placebo groups (P=0.038) was significant at T20. CLINICAL SIGNIFICANCE: This study demonstrated that 700 microg/kg ketamine given intravenously postoperatively followed by a six-hour ketamine CRI of 10 microg/kg/minute improved patient feeding behaviour.     

Comparison of postoperative effects between lidocaine infusion,meloxicam, and their combination in dogs undergoing ovariohysterectomy

ObjectiveTo compare the postoperative analgesic effects of intravenous (IV) lidocaine, meloxicam, and their combination in dogs undergoing ovariohysterectomy.Study designProspective, randomized, double‐blind, controlled clinical trial.AnimalsTwenty‐seven dogs aged (mean ± SD) 16.1 ± 7.5 months and weighing 22.4 ± 17.9 kg scheduled for ovariohysterectomy.MethodsAnaesthesia was induced with propofol and maintained with isoflurane. Dogs (n = 9 in each group) were allocated to receive just prior to and during surgery one of the following regimens: M group, 0.2 mg kg^?1 IV meloxicam then a continuous rate infusion (CRI) of lactated Ringer's at 10 mL kg^?1 hour^?1; L group, a bolus of lidocaine (1 mg kg^?1 IV) then a CRI of lidocaine at 0.025 mg kg^?1 minute^?1; and M + L group, both the above meloxicam and lidocaine treatments. Pain and sedation were scored, and venous samples taken for serum cortisol and glucose measurement before and at intervals for 12 hours after anaesthesia. Pain scores were assessed using a multi‐parameter subjective scoring scale (cumulative scale 0–21) by three observers. The protocol stated that dogs with a total score exceeding 9 or a sub‐score above 3 in any one category would receive rescue analgesia. Sedation was scored on a scale of 0–4.ResultsThere were no significant differences in subjective pain scores, serum cortisol, and glucose concentrations between the three groups. The highest pain score at any time was 5, and no dog required rescue analgesia. None of the three regimens caused any observable side effects during or after anaesthesia. At 1 and 2 hours after extubation dogs in group L were significantly more sedated than in the other two groups.Conclusions and Clinical relevanceThis study suggests that, with the scoring system used, IV lidocaine and meloxicam provide similar and adequate post‐operative analgesia in healthy dogs undergoing ovariohysterectomy.