Effects of Ropivacaine-sufentanil Epidural Analgesia on Labor and Maternal and Neonatal Outcomes

[Objectives]This study aimed to investigate the effects of ropivacaine-sufentanil epidural analgesia on labor and maternal and neonatal outcomes.[Methods]A tota...     

Contrast enhanced ultrasonography of kidney in conscious and anesthetized beagle dogs

Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinary medicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this study was to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs using CEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manual restraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZM group) or medetomidine (M group). The contrast agent (Sonovue^®) was administered as an IV bolus. The peak intensity (PI), time to peak enhancement from injection (TTP₀) and the time to peak enhancement from the initial rise (TTP_up), upslope, downslope and area under the curve (AUC) were analyzed. Compared to the cortical values in the conscious group, TTP₀ was significantly delayed in the TZM group, and upslope, TTP₀ and TTP_up were significantly different in the M group. The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renal medullary perfusion was significantly decreased in the TZM and M groups. TTP₀ and TTP_up were also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the M group. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data may serve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia.     

The effect of erector spinae plane block on perioperative analgesic consumption and complications in dogs undergoing hemilaminectomy surgery: a retrospective cohort study

ObjectiveTo compare the perioperative use of analgesics and complication rates in dogs administered an erector spinae plane (ESP) block or a traditional opioid-based (OP) treatment as part of analgesic management during hemilaminectomy.Study designRetrospective cohort study.AnimalsMedical records of 114 client-owned dogs.MethodsGeneral data included demographics, duration of procedure, number of laminae fenestrated, perioperative use of steroid and non-steroidal anti-inflammatory drugs. Intra- and postoperative analgesics used in 48 hours and complications rates were compared between groups. Opioid use was expressed in morphine equivalents [ME (mg kg^?1)]. Continuous data were compared using the Mann–Whitney U test and incidence of events with a Fisher's exact tests. Multiple linear regression was used to evaluate association between perioperative ME consumption (dependent variable) with other independent variables. Data are presented as median (range). Differences were considered significant when p < 0.05.ResultsGroup ESP comprised 42 dogs and group OP 72 dogs. No differences were observed in the general data. Intraoperative ME was 0.65 (0.20–3.74) and 0.79 (0.19–5.60) mg kg^?1 in groups ESP and OP, respectively (p = 0.03). Intraoperative infusion of lidocaine was administered intravenously (IV) to 23.8% and 68% of groups ESP and OP, respectively (p < 0.0001). Intraoperative infusion of ketamine was administered IV to 21% and 40% of groups ESP and OP, respectively (p = 0.04). Regression analysis revealed the ESP block as the only independent variable affecting the perioperative ME consumption. Pharmacological intervention to treat cardiovascular complications was administered to 21.4% and 47.2% of dogs in groups ESP and OP, respectively (p = 0.008). There were no differences in postoperative complication rates.Conclusions and clinical relevanceESP block was associated with reduced perioperative opioid consumption, intraoperative adjuvant analgesic use and incidence of pharmacological interventions to treat cardiovascular complications in dogs undergoing hemilaminectomy.     

Hemodynamic effects of incremental doses of acepromazine in isoflurane-anesthetized dogs

ObjectiveTo evaluate the effects of incremental doses of acepromazine on hemodynamics in isoflurane-anesthetized dogs.Study designProspective, experimental study.AnimalsHealthy, adult, mixed-breed dogs (two male and four female) weighing 16.8 ± 5.1 kg (mean ± standard deviation).MethodsDogs were anesthetized with propofol (7 mg kg^–1) intravenously (IV) and isoflurane. Thermodilution and arterial catheters were placed for hemodynamic monitoring and arterial blood sampling for blood gas analysis. Baseline measurements were performed with stable expired concentration of isoflurane (Fe′Iso) at 1.8%. Each dog was then administered four incremental acepromazine injections (10, 15, 25 and 50 μg kg^–1) IV, and measurements were repeated 20 minutes after each acepromazine injection with Fe′Iso decreased to 1.2%. The four acepromazine injections resulted in cumulative doses of 10, 25, 50 and 100 μg kg^–1 (time points ACP₁₀, ACP₂₅, ACP₅₀ and ACP₁₀₀, respectively).ResultsCompared with baseline, cardiac index (CI) increased significantly by 34%, whereas systemic vascular resistance index (SVRI) decreased by 25% at ACP₅₀ and ACP₁₀₀. Arterial oxygen content (CaO₂) was significantly lower than baseline after all acepromazine injections (maximum decreases of 11%) and was lower at ACP₅₀ and ACP₁₀₀ than at ACP₁₀. No significant change was found in heart rate, stroke index, oxygen delivery index and systolic, mean and diastolic blood pressures. Hypotension (mean arterial pressure < 60 mmHg) was observed in one dog at baseline, ACP₁₀, ACP₂₅ and ACP₁₀₀, and in two dogs at ACP₅₀.Conclusions and clinical relevanceCompared with isoflurane alone, anesthesia with acepromazine–isoflurane resulted in increased CI and decreased SVRI and CaO₂ values. These effects were dose-related, being more pronounced at ACP₅₀ and ACP₁₀₀. Under the conditions of this study, acepromazine administration did not change blood pressure.     

Definition and clinical evaluation of a recruiting airway pressure based on the specific lung elastance in anesthetized dogs

ObjectiveTo determine the specific lung elastance (SE_L) in anesthetized dogs and to evaluate the efficacy of a SE_L-based recruiting airway pressure (RP_aw) at improving global and regional lung aeration.Study designRetrospective and prospective clinical study.AnimalsA total of 28 adult dogs were included in the retrospective study and six adult dogs in the prospective study.MethodsRetrospective study: SE_L and SE_L-based RP_aw were determined using previously published data. In mechanically ventilated dogs undergoing thoracic computed tomography (CT), SE_L was calculated as ΔP_L/(V_T/EELV), where ΔP_L is the driving transpulmonary pressure, V_T is the tidal volume and EELV is the end-expiratory lung volume. The ratio of lung to respiratory system elastance (E_L/E_rs) was determined. SE_L and E_L/E_rs were used to calculate the SE_L-based RP_aw. Prospective study: dogs underwent thoracic CT at end-expiration and at end-inspiration using the SE_L-based RP_aw, and global and regional aeration was determined. For analysis of regional aeration, lungs were divided into cranial, intermediate and caudal regions. Regional compliance was also calculated. A p value <0.05 was considered significant.ResultsThe SE_L and E_L/E_rs were 12.7 ± 3.1 cmH₂O and 0.54 ± 0.07, respectively. The SE_L-based RP_aw was 29.1 ± 7.6 cmH₂O. In the prospective study, the RP_aw was 28.2 ± 1.3 cmH₂O. During RP_aw, hyperinflation increased (p = 0.0003) whereas poorly aerated (p < 0.0001) and nonaerated (p = 0.01) tissue decreased. Normally aerated tissue did not change (p = 0.265). Regional compliance was higher in the intermediate (p = 0.0003) and caudal (p = 0.034) regions compared with the cranial region. Aeration did not differ between regions (p > 0.05).Conclusions and clinical relevanceAn SE_L-based RP_aw reduces poorly and nonaerated lung tissue in anesthetized dogs. In nonsurgical anesthetized dogs, an RP_aw near 30 cmH₂O is effective at improving lung aeration.     

Ultrasound-guided modified subcostal transversus abdominis plane block and influence of recumbency position on dye spread in equine cadavers

ObjectiveTo describe and evaluate an ultrasound-guided modified subcostal approach for the transversus abdominis plane (TAP) block in horse cadavers in lateral or dorsal recumbency.Study designProspective, experimental cadaveric study.AnimalsStudy of one preserved foal and eight fresh adult horse cadavers.MethodsThe lateral and ventral abdominal wall of a preserved cadaver was dissected to identify the muscles and nerves. A unilateral standard TAP block technique was performed (60 mL of methylene blue dye–bupivacaine) on a fresh cadaver in right lateral recumbency. A modified subcostal technique was performed on the opposite side using a linear ultrasound transducer and in-plane approach. Injection points (two 30 mL dye) were at the level of the TAP (between the rectus abdominis and transversus abdominis muscles and ventral to the cutaneous trunci muscle) perpendicular to: 1) the mid-point between the xiphoid cartilage and umbilical scar; and 2) at a point between the caudal and middle thirds of the abdomen measured from the first injection point to the umbilical scar. The modified subcostal approach was performed in seven additional cadavers in both hemiabdomens, with three cadavers in lateral and four cadavers in dorsal recumbency. Ultrasound guidance was used with all injections.ResultsThe standard approach stained the sixteenth to eighteenth thoracic nerves (T16–T18). The modified subcostal approach performed in lateral recumbency provided greater spread (T9–T17) than dorsal recumbency (T12–T18) (p = 0.016).Conclusions and clinical relevanceThe modified subcostal TAP approach resulted in extensive staining exceeding the standard approach. The nerves stained are consistent with production of ventral abdominal wall anesthesia in horses. Clinical studies are needed to verify these findings.     

Evaluation of the analgesic effect of fentanyl–ketamine and fentanyl–lidocaine constant rate infusions in isoflurane-anesthetized dogs undergoing thoracolumbar hemilaminectomy

ObjectiveTo evaluate anesthetic conditions and postoperative analgesia with the use of intraoperative constant rate infusions (CRIs) of fentanyl–lidocaine or fentanyl–ketamine in dogs undergoing thoracolumbar hemilaminectomy.Study designProspective, randomized, blinded, clinical study.AnimalsA total of 32 client-owned dogs.MethodsDogs were premedicated with fentanyl (5 μg kg^–1) administered intravenously (IV), anesthesia was induced with IV alfaxalone and maintained with isoflurane. Fentanyl (0.083 μg kg^–1 minute^–1) was infused IV with either ketamine (0.5 mg kg^–1; then 40 μg kg^–1 minute^–1; group KF) or lidocaine (2 mg kg^–1; then 200 μg kg^–1 minute^–1; group LF) assigned randomly. Heart rate, noninvasive arterial pressures, respiratory rate, esophageal temperature, end-tidal partial pressure of carbon dioxide and isoflurane concentration were recorded throughout anesthesia. Maintenance of anesthesia, recovery and postoperative pain (Glasgow Composite Pain Scale) were scored. Cardiopulmonary data were analyzed using a two-way anova with repeated measures, demographics of the two groups with a t test, and scores with Mann–Whitney U test, with p < 0.05.ResultsAll dogs recovered from anesthesia without complications. No significant difference was found between groups for cardiopulmonary variables, total anesthesia time, sedation score and requirement for postoperative sedation or for rescue analgesia. Anesthetic maintenance score was of lower quality in KF than in LF [median (interquartile range): 0 (0–0.5) versus 0 (0–0); p = 0.032)], but still considered ideal. Recovery score was higher and indicative of less sedation in LF than in KF [1 (1–1.5) versus 0.5 (0–1); p < 0.0001]. Pain score was higher in KF than in LF [2 (1–3) versus 1 (1–2); p = 0.0009].Conclusions and clinical relevanceBoth CRIs of KF and LF provided adequate anesthetic conditions in dogs undergoing thoracolumbar hemilaminectomy. Based on requirement for rescue analgesia, postoperative analgesia was adequate in both groups.     

Questionnaire on the process of recovering horses from general anesthesia and associated personnel injury in equine practice

ObjectiveTo collect data about the current practice of recovering horses from general anesthesia and recovery personnel safety.Study designOnline survey.MethodsAn online questionnaire, including questions on general demographic data, recovery drugs, modality and characteristics of equine recovery and morbidity and mortality, was designed and distributed via e-mail to equine practitioners worldwide.ResultsPractitioners from 22 countries completed 373 questionnaires; 53% of the participants were board-certified equine surgeons, and the remainder were board-certified anesthesiologists (18%), large animal residents (8%), general practitioners (7%), large animal interns (6%), anesthesia residents (4.5%) and veterinary technicians (1.6%). Respondents were employed by academia (58%) or private practice (42%). Of the respondents employed at a university, 93% had a board-certified anesthesiologist on staff compared with 7% of respondents employed at a private practice. Most of the respondents assist horses during recovery, with 23% assisting every recovery and 44% assisting recovery in the majority of cases. Reasons for choosing to assist horses during recovery were: orthopedic procedures (57%), neurological deficits (49%), bad health (47%), history of poor recovery (44%), foals (42%), draft breeds (30%), magnetic resonance imaging (17%) and computed tomography (16%). Unacceptable recoveries were reported by 77% of participants. Commonly reported complications during recovery with any method were: orthopedic injury (66%), myopathy (54%), skin abrasion (53%) and airway obstruction (37%). The incidences of unacceptable quality of recovery (p = 0.09) or personnel injury (p = 0.56) were not different between assisted and nonassisted recoveries; however, more equine fatalities were reported for assisted recoveries (p < 0.006). Practitioners in academia reported more unacceptable recoveries (p < 0.0007) and personnel injuries (p < 0.002) compared with those in private practice.ConclusionsThe method of recovery differs among hospitals. Recovery personnel injuries associated with assisting horses during recovery are an important and previously unreported finding.     

Evaluation of neuraxial administration of bupivacaine in bearded dragons (Pogona vitticeps)

ObjectiveTo assess the success rate, onset, duration and extent of motor/sensory block following neuraxial injection of two dosages of bupivacaine in bearded dragons (Pogona vitticeps).Study designProspective, randomized, blinded, crossover experimental study.AnimalsA total of 10 adult bearded dragons (0.3 ± 0.1 kg).MethodsAfter sedation with alfaxalone (15 mg kg^–1 subcutaneously), neuraxial injections were performed with 1 or 2 mg kg^–1 bupivacaine hydrochloride (0.5%, treatments BUP-1 and BUP-2, respectively) in a randomized treatment sequence with a 7 day washout period. If the initial bupivacaine injection was not successful within 10 minutes, a second injection was performed at the same dose. Mechanical stimulation of limbs, 25%, 50%, 75% of the trunk’s length and cloacal tone were assessed.ResultsSuccess rate following the first neuraxial injection was 95%, which increased to 100% after the second injection. Motor/sensory block were noted by 5 minutes after the injection of bupivacaine at either dose. BUP-2 was associated with more cranial spread. The median (range) duration of cloacal tone loss was longer following treatment BUP-2 [120 (75–225) minutes] than followed treatment BUP-1 [83 (25–135) minutes; p = 0.03]. Duration of pelvic limb motor block was comparable between both doses, lasting a median of 68 minutes in both treatments (p = 0.94). There was a transient, not clinically relevant increase from baseline in heart rate in treatment BUP-1 only. No significant difference from baseline in respiratory rate was noted in either treatment; however, two animals in treatment BUP-2 became apneic (10–20 minutes).Conclusions and clinical relevanceBupivacaine (1 mg kg^–1) is recommended for neuraxial anesthesia in bearded dragons. In treatment BUP-2, extensive cranial spread resulted in apnea and motor block of the thoracic limb in several animals; therefore this dose is not recommended.