Anestesia regional y periférica guiada por ultrasonido en el paciente critico

El presente trabajo es un capítulo de libro titulado “Anestesia Regional y Periférica Guiada por Ultrasonido en el Paciente Crítico” que será incluido en la última edición del libro “Manual de Ultrasonido en Terapia Intensiva y Emergencias” cuyo editor es el Doctor José de Jesús Rincón Salas y que será publicado por la Editorial Prado de México para distribución latinoamericana desde dicho país. Por solicitud del editor y teniendo en cuenta el enfoque del libro, el presente trabajo está dirigido a estudiantes de formación, médicos graduados y especialistas en las áreas de cuidado intensivo, anestesiología, dolor, medicina interna y medicina de urgencias. Tiene como propósito empapar de conocimientos necesarios y prácticos en anestesia regional a personas que usualmente no han tenido contacto con la anestesia regional, pues desafortunadamente sólo en los últimos años ha sido posible que la anestesia regional haya comenzado a salir de las salas de cirugía, ámbito donde ha estado confinada tradicionalmente. El lenguaje utilizado es sencillo y el capítulo ha sido escrito para que sea fácil de leer y consultar, dejando así mensajes muy claros sobre la utilidad, viabilidad e implicaciones que tiene el uso de anestesia regional guiada por ultrasonido en cuidado intensivo. Los autores esperamos que de esta manera, el presente capítulo permita continuar superando los obstáculos que se interponen entre los invaluables beneficios de la anestesia regional y los pacientes de cuidado intensivo que necesitan de ella.

Acupuncture with manual and electrical stimulation for labour pain : a longitudinal randomised controlled trial

Background: Acupuncture is commonly used to reduce pain during labour despite contradictory results. The aim of this study is to evaluate the effectiveness of acupuncture with manual stimulation and acupuncture with combined manual and electrical stimulation (electro-acupuncture) compared with standard care in reducing labour pain. Our hypothesis was that both acupuncture stimulation techniques were more effective than standard care, and that electro-acupuncture was most effective.  Methods: A longitudinal randomised controlled trial. The recruitment of participants took place at the admission to the labour ward between November 2008 and October 2011 at two Swedish hospitals. 303 nulliparous women with normal pregnancies were randomised to: 40 minutes of manual acupuncture (MA), electro-acupuncture (EA), or standard care without acupuncture (SC). Primary outcome: labour pain, assessed by Visual Analogue Scale (VAS). Secondary outcomes: relaxation, use of obstetric pain relief during labour and post-partum assessments of labour pain. The sample size calculation was based on the primary outcome and a difference of 15 mm on VAS was regarded as clinically relevant, this gave 101 in each group, including a total of 303 women.  Results: Mean estimated pain scores on VAS (SC: 69.0, MA: 66.4 and EA: 68.5), adjusted for: treatment, age, education, and time from baseline, with no interactions did not differ between the groups (SC vs MA: mean difference 2.6, 95% confidence interval [CI] -1.7-6.9 and SC vs EA: mean difference 0.6 [95% CI] -3.6-4.8). Fewer number of women in the EA group used epidural analgesia (46%) than women in the MA group (61%) and SC group (70%) (EA vs SC: odds ratio [OR] 0.35; [95% CI] 0.19-0.67).  Conclusions: Acupuncture does not reduce women's experience of labour pain, neither with manual stimulation nor with combined manual and electrical stimulation. However, fewer women in the EA group used epidural analgesia thus indicating that the effect of acupuncture with electrical stimulation may be underestimated. These findings were obtained in a context with free access to other forms of pain relief.

Acupuncture with manual and electrical stimulation for labour pain : a two month follow up of recollection of pain and birth experience.

BACKGROUND: In a previous randomised controlled trial we showed that acupuncture with a combination of manual- and electrical stimulation (EA) did not affect the level of pain, as compared with acupuncture with manual stimulation (MA) and standard care (SC), but reduced the need for other forms of pain relief, including epidural analgesia. To dismiss an under-treatment of pain in the trial, we did a long-term follow up on the recollection of labour pain and the birth experience comparing acupuncture with manual stimulation, acupuncture with combined electrical and manual stimulation with standard care. Our hypothesis was that despite the lower frequency of use of other pain relief, women who had received EA would make similar retrospective assessments of labour pain and the birth experience 2 months after birth as women who received standard care (SC) or acupuncture with manual stimulation (MA). METHODS: Secondary analyses of data collected for a randomised controlled trial conducted at two delivery wards in Sweden. A total of 303 nulliparous women with normal pregnancies were randomised to: 40 min of MA or EA, or SC without acupuncture. Questionnaires were administered the day after partus and 2 months later. RESULTS: Two months postpartum, the mean recalled pain on the visual analogue scale (SC: 70.1, MA: 69.3 and EA: 68.7) did not differ between the groups (SC vs MA: adjusted mean difference 0.8, 95 % confidence interval [CI] -6.3 to 7.9 and SC vs EA: mean difference 1.3 CI 95 % -5.5 to 8.1). Positive birth experience (SC: 54.3 %, MA: 64.6 % and EA: 61.0 %) did not differ between the groups (SC vs MA: adjusted Odds Ratio [OR] 1.8, CI 95 % 0.9 to 3.7 and SC vs EA: OR 1.4 CI 95 % 0.7 to 2.6). CONCLUSIONS: Despite the lower use of other pain relief, women who received acupuncture with the combination of manual and electrical stimulation during labour made the same retrospective assessments of labour pain and birth experience 2 months postpartum as those who received acupuncture with manual stimulation or standard care. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01197950.

Acupuncture for labour pain

Background: Acupuncture involves puncturing the skin with thin sterile needles at defined acupuncture points. Previous studies are inconclusive regarding the effect of acupuncture on labour pain, but some studies have found a reduction in the use of pharmacological pain relief when acupuncture is administered. The appropriate dose of acupuncture treatment required to elicit a potential effect on labour pain has not been fully explored. The dose is determined by many different factors, including the number of needles used and the intensity of the stimulation. In Sweden, manual stimulation of the needles is common practice when acupuncture is used for labour pain, but electrical stimulation of the needles, which gives a higher dose, could possibly be more effective. The overall aim of this thesis was to evaluate the effectiveness of acupuncture with manual stimulation (MA) of the needles as well as acupuncture with a combination of manual and electrical stimulation (EA) in reducing labour pain, compared with standard care without any form of acupuncture (SC). Methods: The study was designed as a three-armed randomised controlled trial in which 303 nulliparous women with normal pregnancies were randomised to MA, EA, or SC. The primary outcome was labour pain, assessed using the Visual Analogue Scale (VAS). Secondary outcomes were relaxation during labour, use of obstetric pain relief, and associations between maternal characteristics and labour pain and use of epidural analgesia respectively. Also, labour and infant outcomes, recollection of labour pain, and maternal experiences, such as birth experience and experience of the midwife, were investigated two months after the birth. The sample size calculation was based on the potential to discover a difference of 15 mm on the VAS. Data were collected during labour before the interventions, the day after birth, and two months later. Besides using the VAS, information was collected by means of study specific protocol, questionnaires and medical records. Results: The mean VAS scores were 66.4 in the MA group, 68.5 in the EA group, and 69.0 in the SC group (mean differences: MA vs. SC 2.6 95% CI -1.7 to 6.9, and EA vs. SC 0.6 95% CI -3.6 to 4.8). Other methods of pain relief were used less frequently in the EA group, including epidural analgesia, MA 61.4%, EA 46%, and SC 69.9%. (EA vs. SC OR 0.4 95% CI 0.2 to 0.7). No statistically significant differences were found in the recollection of labour pain between the three groups two months after birth (mean VAS score: MA 69.3, EA 68.7 and SC 70.1). A few maternal characteristics were associated with labour pain (age, dysmenorrhea, and cervix dilatation), but none of the investigated characteristics predicted the outcome of the acupuncture treatment in MA or EA. Women in the EA group experienced acupuncture as being effective for labour pain to a higher extent than women who received MA, MA 44.4%, EA 67.1% (EA vs. MA OR 2.4 95% CI 1.2 to 4.8). Women in the EA group also spent less time in labour (mean 500 min) than those who received MA (mean 619 min) and SC (mean 615 min) (EA vs. MA HR 1.4 95% CI 1.0 to1.9, EA vs. SC HR 1.4, 95% CI 1.1 to 2.0), and had less blood loss than women receiving SC, (EA vs. SC OR 0.1 95% CI 0.3 to 0.7). The women’s assessment of the midwife as being supportive during labour (MA 77.2%, EA 83.5%, SC 80%), overall satisfaction with midwife care (MA 100%, EA 97.5%, SC 98.7%), and having an overall positive childbirth experience (MA 64.6%, EA 61.0%, SC 54.3%) did not differ statistically. No serious side effects of the acupuncture treatment were reported. Conclusion: Acupuncture, regardless of type of stimulation, did not differ from standard care without acupuncture in terms of reducing women’s experience of pain during labour, or their memory of pain and childbirth overall two months after the birth. However, other forms of obstetric pain relief were less frequent in women receiving a combination of manual and electrical stimulation, suggesting that this method could facilitate coping with labour pain.

Efeitos analgésicos da neostigmina e morfina, isoladas ou associadas, pela via peridural em cadelas submetidas à ovariosalpingohisterectomia(OSH)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relazione gestante-feto, modalità del parto e sviluppo fisico del bambino

Extensive literature outlined that the quality of the mother-foetus relationship is considered the main feature with regard to the quality of postnatal mother-infant interaction and also to the child’s psychical development. Nowadays the relationship between the pregnant woman and her foetus is viewed as the central factor of the somatic dialogue between the functioning of the maternal and the foetal organisms. This dialogue is responsible for the physic development of the child, as well as of its psychosomatic structure. Therefore the research area has necessarily had to extend to the analysis of psychological processes concerning: the pregnancy, the couple that is bound by parenthood, the influence of intergenerational dynamics. In fact, the formation of maternal identity, as well as that of the relationship between the woman and the foetus, refers to the pregnant woman’s relationship with her parents, especially with her mother. The same pregnancy, considered as a psychosomatic event, is directly influenced by relational, affective and social factors, particularly by the quality of the interiorized parental relations and the quality of the current relationships (such as that with her partner and with her family of origin). Some studies have begun to investigate the relationship between the pregnant woman and the foetus in term of “prenatal attachment” and its relationship with socio-demographic, psychological e psychopathological aspects (such as pre and post partum depression), but the research area is still largely unexplored. The present longitudinal research aimed to investigate the quality of the pregnant womanfoetus relationship by the prenatal attachment index, the quality of the interiorized relationship with woman’s parents, the level of alexithymic features and maternity social support, in relation with the modulation of the physiology of delivery and of postpartum, as well as of the physical development of the child. A consecutive sample of 62 Italian primipara women without any kind of pathologies, participated in the longitudinal study. In the first phase of this study (third trimester of the pregnancy), it has investigated the psychological processes connected to the affective investment of the pregnant women towards the unborn baby (by Prenatal Attachment Inventory), the mothers’ interiorized relationship with their own parents (by Parental Bonding Instrument), the social and affective support from their partner and their family of origin are able to supply (by Maternity Social Support Scale), and the level of alexithymia (by 20-Toronto Alexithymia Scale). In the second phase of this study, some data concerning the childbirth course carried out from a “deliverygram” (such as labour, induction durations and modalities of delivery) and data relative to the newborns state of well-being (such as Apgar and pH indexes). Finally, in the third phase of the study women have been telephoned a month after the childbirth. The semistructured interview investigated the following areas: the memory concerning the delivery, the return to home, the first interactions between the mother and the newborn, the breastfeeding, the biological rhythms achieved from newborns. From the data analysis a sample with a good level of prenatal attachment and of support social and a good capability to mental functioning emerged. An interesting result is that the most of the women have a great percentage of “affectionless control style” with both parents, but data is not sufficient to interpret this result. Moreover, considering the data relative to the delivery, medical and welfare procedures, that have been necessary, are coherent with the Italian mean, while the percentage of the caesarean section (12.9%) is inferior to the national percentage (30%). The 29% of vaginal partum has got epidural analgesia, which explains the high number (37%) of obstetrician operations (such as Kristeller). The data relative to the newborn (22 male, 40 female) indicates a good state of well-being because Apgar and pH indexes are superior to 7 at first and fifth minutes. Concerning the prenatal phase, correlation analysis showed that: the prenatal attachment scores positively correlated with the expected social support and negatively correlated with the “externally oriented thinking” dimension of alexithymia; the maternity social support negatively correlated with total alexithymia score, particularly with the “externally oriented thinking” dimension, and negatively correlated with maternal control of parental bonding. Concerning the delivery data, there are many correlations (after all obvious) among themselves. The most important are that the labour duration negatively correlated with the newborn’s index state of well-being. Finally, concerning the data from the postpartum phase the women’ assessments relative to the partum negatively correlated with the duration of the delivery and positively correlated with the assessment relative to the return to home and the interaction with the newborn. Moreover the length of permanence in the hospital negatively correlated with women’s assessments relative to the return to home that, in turn, positively correlated with the quality of breastfeeding, the interaction between the mother and the newborn and the biological regulation of the child. Finally, the women’ assessments relative to breastfeeding positively correlated with the mother-child interactions and the biological rhythms of children. From the correlation analysis between the variables of the prenatal phase and the data relative to the delivery, emerged that the prenatal attachment scores positively correlated with the dilatation stage scores and with the newborn’s Apgar index at first minute, the paternal care dimension of parental bonding positively correlated with the lengths of the various periods of childbirth like so the paternal control dimension with placental stage. Moreover, emerged that the expected social support positively correlated with the lengths of the various periods of childbirth and that the global alexithymia scores, particularly “difficulty to describe emotions” dimension, negatively correlated with total childbirth scores. From the correlation analysis between the variables of the prenatal phase and variable of the postpartum phase emerged that the total alexithymia scores positively correlated with the time elapsed from the childbirth to the breastfeeding of the child, the difficulty to describe emotions dimension of the alexithymia negatively correlated with the quality of the breastfeeding, the “externally oriented thinking” dimension of the alexithymia negatively correlated with mother-child interactions, and finally the paternal control dimension of the parental bonding negatively correlated with the time elapsed from the child to the breastfeeding of the child. Finally, from the analysis of the correlation between the data of the partum and the women’s assessments of the postpartum phase, emerged the negative correlation between the woman’s assessment relative to the delivery and the quantitative of obstetrician operations and the lengths of the various periods of childbirth, the positive correlation between the women’s assessment about the length of delivery periods and the real lengths of the same ones, the positive relation between woman’s assessment relative to the delivery and the Apgar index of children. In conclusion, there is a remarkable relation between the quality of the relationship the woman establishes with the foetus that influences the course of the pregnancy and the delivery that, in turn, influences the postpartum outcome, particularly relative to the mother-children relationship. Such data should be confirmed by heterogeneous populations in order to identify vulnerable women and to project focused intervention.

Potential influence of the anesthetic technique used during open radical prostatectomy on prostate cancer-related outcome: a retrospective study

Recently published studies suggest that the anesthetic technique used during oncologic surgery affects cancer recurrence. To evaluate the effect of anesthetic technique on disease progression and long-term survival, we compared patients receiving general anesthesia plus intraoperative and postoperative thoracic epidural analgesia with patients receiving general anesthesia alone undergoing open retropubic radical prostatectomy with extended pelvic lymph node dissection.

Intraoperative Continuous Norepinephrine Infusion Combined with Restrictive Deferred Hydration Significantly Reduces the Need for Blood Transfusion in Patients Undergoing Open Radical Cystectomy: Results of a Prospective Randomised Trial

BACKGROUND Open radical cystectomy (ORC) is associated with substantial blood loss and a high incidence of perioperative blood transfusions. Strategies to reduce blood loss and blood transfusion are warranted. OBJECTIVE To determine whether continuous norepinephrine administration combined with intraoperative restrictive hydration with Ringer's maleate solution can reduce blood loss and the need for blood transfusion. DESIGN, SETTING, AND PARTICIPANTS This was a double-blind, randomised, parallel-group, single-centre trial including 166 consecutive patients undergoing ORC with urinary diversion (UD). Exclusion criteria were severe hepatic or renal dysfunction, congestive heart failure, and contraindications to epidural analgesia. INTERVENTION Patients were randomly allocated to continuous norepinephrine administration starting with 2 μg/kg per hour combined with 1 ml/kg per hour until the bladder was removed, then to 3 ml/kg per hour of Ringer's maleate solution (norepinephrine/low-volume group) or 6 ml/kg per hour of Ringer's maleate solution throughout surgery (control group). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Intraoperative blood loss and the percentage of patients requiring blood transfusions perioperatively were assessed. Data were analysed using nonparametric statistical models. RESULTS AND LIMITATIONS Total median blood loss was 800 ml (range: 300-1700) in the norepinephrine/low-volume group versus 1200 ml (range: 400-2800) in the control group (p<0.0001). In the norepinephrine/low-volume group, 27 of 83 patients (33%) required an average of 1.8 U (±0.8) of packed red blood cells (PRBCs). In the control group, 50 of 83 patients (60%) required an average of 2.9 U (±2.1) of PRBCs during hospitalisation (relative risk: 0.54; 95% confidence interval [CI], 0.38-0.77; p=0.0006). The absolute reduction in transfusion rate throughout hospitalisation was 28% (95% CI, 12-45). In this study, surgery was performed by three high-volume surgeons using a standardised technique, so whether these significant results are reproducible in other centres needs to be shown. CONCLUSIONS Continuous norepinephrine administration combined with restrictive hydration significantly reduces intraoperative blood loss, the rate of blood transfusions, and the number of PRBC units required per patient undergoing ORC with UD.

The effects of thoracic epidurally administered drugs on urethral sphincter function in women: a pooled analysis

OBJECTIVES Thoracic epidural analgesia (TEA) has been shown to inhibit detrusor activity in patients undergoing open renal surgery, resulting in clinically relevant post-void residuals. However, the impact of different epidural drug mixtures on urethral sphincter function is not completely elucidated. DESIGN Pooled analysis of an open observational study and a double-blind randomized trial. SETTING Single tertiary centre. SUBJECTS Twenty-eight women without lower urinary tract symptoms and post-void residual <100 mL, who underwent open renal surgery with TEA. METHODS Pooling results in three groups with different epidural regimens (7 with bupivacaine 0.125%, 8 with bupivacaine 0.125% and fentanyl 2 μg/mL, and 13 with bupivacaine 0.1% plus fentanyl 2 μg/mL and epinephrine 2 μg/mL). All women underwent urethral pressure measurements before TEA and during TEA 2-3 days postoperatively. All patients received a TEA placed at the insertion site interspace T 8-9. RESULTS Maximum urethral closure pressure at rest decreased significantly during TEA with bupivacaine alone (median 70 cm H2 O [interquartile range 66-76] to 43 [43-65], P = 0.031) and with bupivacaine/fentanyl/epinephrine (75 cm H2 O [68-78] to 56 [52-75], P = 0.028), whereas with bupivacaine/fentanyl, no significant change could be detected (74 [51-88] vs 67 [46-70], P = 0.156). In all groups, functional profile length at rest was not influenced during TEA. CONCLUSION TEA with bupivacaine and the addition of fentanyl and epinephrine appears to decrease maximum urethral closure pressure at rest in women. The addition of fentanyl alone to bupivacaine may reduce this effect. Thus, the TEA effect on urethral sphincter function seems to depend on the drug mixture administered.

New perioperative fluid and pharmacologic management protocol results in reduced blood loss, faster return of bowel function, and overall recovery.

Cystectomy and urinary diversion have high morbidity, and strategies to reduce complications are of utmost importance. Epidural analgesia and optimized fluid management are considered key factors contributing to successful enhanced recovery after surgery. In colorectal surgery, there is strong evidence that an intraoperative fluid management aiming for a postoperative zero fluid balance results in lower morbidity including a faster return of bowel function. Recently, a randomized clinical trial focusing on radical cystectomy demonstrated that a restrictive intraoperative hydration combined with a concomitant administration of norepinephrine reduced intraoperative blood loss, the need for blood transfusion and morbidity. The purpose of this review is to highlight specific anesthesiological aspects which have been shown to improve outcome after RC with urinary diversion.

Clinicians' evaluations of fetal oximetry sensor placement in a multicentre randomised trial (the FOREMOST trial)

Background: Fetal pulse oximetry (FPO) may improve the assessment of the fetal well-being in labour. Reports of health-care provider's evaluations of new technology are important in the overall evaluation of that technology. Aims: To determine doctors' and midwives' perceptions of their experience placing FPO sensors. Methods: We surveyed clinicians (midwives and doctors) following placement of a FPO sensor during the FOREMOST trial (multicentre randomised trial of fetal pulse oximetry). Clinicians rated ease of sensor placement (poor, fair, good and excellent). Potential influences on ease of sensor placement (staff category, prior experience in Birth Suite, prior experience in placing sensors, epidural analgesia, cervical dilatation and fetal station) were examined by ordinal regression. Results: There were 281 surveys returned for the 294 sensor placement attempts (response rate 96%). Sensors were placed by midwives (29%), research midwives (48%), registrars (22%) and obstetricians (1%). The majority of clinicians had 1 or more years' Birth Suite experience, had placed six or more sensors previously, and rated ease of sensor placement as good. Advancing fetal station (P < 0.001) and the presence of epidural analgesia prior to sensor placement (P = 0.029) predicted improved ease of sensor placement. Having a clinician placing a sensor for the first time predicted a lower rating for ease of sensor placement (P = 0.001), compared to having placed one or more sensors previously. Conclusions: Clinicians with varying levels of Birth Suite experience successfully placed fetal oxygen saturation sensors, with the majority rating ease of sensor placement as good.

Estudo de duas modalidades de analgesia epidural pós-toracotomia : o impacto no desempenho funcional pulmonar e no manejo da dor

Trinta e sete pacientes submetidos à toracotomia póstero-lateral foram submetidos a um estudo prospectivo, randomizado e duplo cego com o objetivo de comparar a eficácia da analgesia epidural torácica com fentanil e bupivacaína versus a analgesia epidural lombar com morfina para o controle da dor e prevenção da deterioração da função pulmonar pós-operatória. A avaliação da dor do paciente, usando-se a escala de cotação numérica de 0 a10 cm foi realizada no pré-operatório e nos primeiros três dias de pós-operatório, três vezes ao dia, com intervalo de 7 horas. A espirometria (CVF,VEF1) foi realizada no pré-operatório e uma vez ao dia nos três dias de pósoperatório. Complicações clínicas,cardiológicas e respiratórias foram analisadas. Foram randomizados 20 pacientes para o grupo que recebeu analgesia epidural torácica e 22 pacientes para o grupo de analgesia epidural lombar. Terminaram o período de avaliação de 3 dias, 10 pacientes do grupo epidural torácico e 9 do grupo epidural lombar. Não houve diferença estatística significativa entre os grupos em relação a escala de dor, deterioração da função pulmonar e complicações clínicas,cardiológicas e respiratórias. Em ambos os grupos, houve uma diminuição na intensidade da dor no decorrer dos dias de estudo. Observou-se uma significativa deterioração da função pulmonar no primeiro dia pós-operatóio, a qual manteve-se nos dois dias subseqüentes. Foi observada uma correlação positiva entre a intensidade da dor e a diminuição da função pulmonar (CVF) no grupo que recebeu analgesia epidural torácica, especialmente durante o 1° e o 3° dia de pós-operatório. O presente estudo demonstrou que tanto analgesia epidural contínua torácica com fentanil e bupivacaína, quanto a epidural contínua lombar com morfina foram eficazes no controle da dor pós-operatória, entretanto não foram capazes de prevenir a deterioração da função pulmonar no período do pós-operatório precoce de toracotomia póstero-lateral.

Analgesia of Epidural Tramadol in Dogs Submitted to Orchiectomy

Epidural tramadol in veterinary medicine has been studied in only a few instances. In this case, 36 dogs submitted to orchiectomy received 6.0 mg/kg of lidocaine combined with 1.0 mg/kg of tramadol, 0.1 mg/kg of morphine or 0.01 ml/kg of 0.9% NaCl by epidural route. Analgesia was assessed at 4, 8, 12, 18 and 24 hours after surgery. There were no differences between morphine and tramadol over the time of evaluation within these groups, and no complementary analgesia was necessary. In the NaCl group, analgesia was needed at 4, 8 and 12 hours. Epidural tramadol provides an analgesic effect comparable to that of morphine during the first 12 hours post-surgery.

Epidural anesthesia and postoperatory analgesia with alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy in bitches

The aim of this study was to determine the viability and cardiorespiratory effects of the association of epidural alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy (OH) in bitches. Forty-two bitches were spayed under epidural anesthesia with 2.5 mg/kg body weight (BW) of 1% lidocaine with adrenaline (CON) or in association with 0.25 mg/kg BW of xylazine (XYL), 10 mu g/kg BW of romifidine (ROM), 30 mu g/kg BW of detomidine (DET), 2 mu g/kg BW of dexmedetomidine (DEX), or 5 mu g/kg BW of clonidine (CLO). Heart rate (HR), respiratory rate (f(R)) and arterial pressures were monitored immediately before and every 10 min after the epidural procedure. Blood gas and pH analysis were done before, and at 30 and 60 min after the epidural procedure. Animals were submitted to isoflurane anesthesia if they presented a slightest sign of discomfort during the procedure. Time of sensory epidural block and postoperative analgesia were evaluated. All animals in CON and DEX, 5 animals in ROM and CLO, 4 animals in XYL, and 3 in DET required supplementary isoflurane. All groups, except CLO, showed a decrease in HR. There was an increase in arterial pressures in all groups. Postoperative analgesia lasted the longest in XYL. None of the protocols were totally efficient to perform the complete procedure of OH; however, xylazine provided longer postoperative analgesia than the others.

Comparison of Epidural and Systemic Tramadol for Analgesia Following Ovariohysterectomy

The objective of the study was to compare epidural and systemic tramadol for postoperative analgesia in bitches undergoing ovariohysterectomy. Twenty animals, randomly divided into two groups, received either epidural (EPI) or intramuscular (IM) tramadol (2 mg/kg) 30 min before anesthetic induction. Analgesia, sedation, cardiorespiratory parameters, end-tidal isoflurane, blood catecholamines and cortisol, and arterial blood gases were measured at different time points up to 24 hr after agent administration. There were no differences between the two groups regarding cardiorespiratory parameters, end-tidal isoflurane, and pain scores. Two dogs in the IM and one in the EPI group required supplemental analgesia. Cortisol was increased (P<0.05) at 120 min (3.59 mu g/dL and 3.27 mu g/dL in the IM and EPI groups, respectively) and 240 min (2.45 mu g/dL and 2.54 mu g/dL in the IM and EPI groups, respectively) compared to baseline. Norepinephrine was also increased (P<0.05) at 120 min in both groups compared to baseline values. Epinephrine values were higher (P<0.05) in the IM group compared with the EPI group at 50 min, 120 min, and 1,440 min after tramadol administration. Epidural tramadol is a safe analgesic, but does not appear to have improved analgesic effects compared with IM administration. (J Am Anim Hosp Assoc 2012; 48:310-319. DOI 10.5326/JAAHA-MS-5795)