Anticipatory prescribing in community end-of-life care in the UK and Ireland during the COVID-19 pandemic: online survey.

BACKGROUND: Anticipatory prescribing (AP) of injectable medications in advance of clinical need is established practice in community end-of-life care. Changes to prescribing guidelines and practice have been reported during the COVID-19 pandemic. AIMS AND OBJECTIVES: To investigate UK and Ireland clinicians' experiences concerning changes in AP during the COVID-19 pandemic and their recommendations for change. METHODS: Online survey of participants at previous AP national workshops, members of the Association for Palliative Medicine of Great Britain and Ireland and other professional organisations, with snowball sampling. RESULTS: Two hundred and sixty-one replies were received between 9 and 19 April 2020 from clinicians in community, hospice and hospital settings across all areas of the UK and Ireland. Changes to AP local guidance and practice were reported: route of administration (47%), drugs prescribed (38%), total quantities prescribed (35%), doses and ranges (29%). Concerns over shortages of nurses and doctors to administer subcutaneous injections led 37% to consider drug administration by family or social caregivers, often by buccal, sublingual and transdermal routes. Clinical contact and patient assessment were more often remote via telephone or video (63%). Recommendations for regulatory changes to permit drug repurposing and easier community access were made. CONCLUSIONS: The challenges of the COVID-19 pandemic for UK community palliative care has stimulated rapid innovation in AP. The extent to which these are implemented and their clinical efficacy need further examination.

Methotrimeprazine versus haloperidol in palliative care patients with cancer-related nausea: a randomised, double-blind controlled trial.

OBJECTIVES: Methotrimeprazine is commonly used for the management of nausea but never tested formally against other drugs used in this setting. The aim was to demonstrate superior antiemetic efficacy. DESIGN: Double-blind, randomised, controlled trial of methotrimeprazine versus haloperidol. SETTING: 11 palliative care sites in Australia. PARTICIPANTS: Participants were >18 years, had cancer, an average nausea score of ≥3/10 and able to tolerate oral medications. Ineligible patients had acute nausea related to treatment, nausea for which a specific antiemetic was indicated, were about to undergo a procedure or had received either of the study drugs or a change in glucocorticoid dose within the previous 48 hours. INTERVENTIONS: Based on previous studies, haloperidol was used as the control. Participants were randomised to encapsulated methotrimeprazine 6·25 mg or haloperidol 1·5 mg one time or two times per day and assessed every 24 hours for 72 hours. MAIN OUTCOME MEASURES: A ≥two-point reduction in nausea score at 72 hours from baseline. Secondary outcome measures were as follows: complete response at 72 hours (end nausea score less than 3), response at 24 and 48 hours, vomiting episodes, use of rescue antiemetics, harms and global impression of change. RESULTS: Response to treatment at 72 hours was 75% (44/59) in the haloperidol (H) arm and 63% (36/57) in the methotrimeprazine (M) arm with no difference between groups (intention-to-treat analysis). Complete response rates were 56% (H) and 51% (M). In the per protocol analysis, there was no difference in response rates: (85% (44/52) (H) and 74% (36/49) (M). Complete per protocol response rates were 64% (H) and 59% (M). Toxicity worse than baseline was minimal with a trend towards greater sedation in the methotrimeprazine arm. CONCLUSION: This study did not demonstrate any difference in response rate between methotrimeprazine and haloperidol in the control of nausea. TRIAL REGISTRATION NUMBER: ACTRN 12615000177550.

The combination of levomepromazine (methotrimeprazine) and rotigotine enables the safe and effective management of refractory nausea and vomiting in a patient with idiopathic Parkinson's disease.

BACKGROUND:: This case report describes a patient with known idiopathic Parkinson's disease, being managed with transdermal rotigotine, whose refractory nausea and vomiting was successfully controlled with subcutaneous levomepromazine. No drug-induced extrapyramidal side effects emerged. CASE PRESENTATION:: A patient was found to have a locally advanced serous carcinoma, causing secondary bowel obstruction. Furthermore, due to compromised oral access, the patient's oral antiparkinsonian medications for motor control were converted to transdermal rotigotine. Unfortunately, the patient's nausea and vomiting was refractory to a number of recommended antiemetic options. CASE MANAGEMENT:: Low dose levomepromazine was administered on a, 'when required' basis, via subcutaneous injection. CASE OUTCOME:: After the first dose of levomepromazine, the patient's nausea and vomiting completely subsided and no extrapyramidal side effects were observed. This was confirmed by daily assessments, revealing no worsening of the motor symptoms associated with idiopathic Parkinson's disease. CONCLUSIONS:: The pharmacology of rotigotine and levomepromazine appear complementary and may allow for the simultaneous use of both drugs, with favourable outcomes. This case report highlights that rotigotine may afford protection against antipsychotic induced extrapyramidal side effects, while preserving antiemetic effects. Such combinations may have a role in the end-of-life management of idiopathic Parkinson's disease.

Trastorno límite de la personalidad y parasomnias / Borderline personality disorder and parasomnias

El trastorno límite de la personalidad es uno de los trastornos más frecuentes. Tiene una comorbilidad variada y amplia. Según diversos artículos, se ha relacionado este trastorno con la presencia de alguno de los tipos de parasomnias, siendo más frecuentes pesadillas y terrores nocturnos. No se conoce un tratamiento específico que sea totalmente efectivo. El tratamiento va más encaminado hacia una mejoría sintomática. El caso que vamos a presentar se trata de una adolescente de 14 años con rasgos de cluster B que ingresa en el hospital por presencia de pesadillas que no se habían mejorado con el abordaje ambulatorio. A través de este caso, hemos realizado una búsqueda bibliográfica para conocer más detalladamente la relación entre parasomnias y el trastorno límite de la personalidad

The borderline personality disorder is one of the most common disorders. It has a varied and extensive comorbidity. According to various articles, this disorder has been linked to the presence of different types of parasomnias, mostly nightmares and night terrors. Treatment is aimed towards symptomatic improvement, since fully effective treatment is unknown. We present a case of a 14 year-old with cluster B traits that were admitted in the hospital through because of nightmares that had not improved with outpatient approach. Through this event, we performed a literature review to learn more about the relationship between parasomnias and borderline personality disorder

The influence of amitriptyline and carbamazepine on levomepromazine metabolism in human liver: an in vitro study.

BACKGROUND: Joint administration of phenothiazine neuroleptics and an antidepressant or carbamazepine is applied in the therapy of many complex psychiatric disorders. The aim of the present study was to investigate possible effects of the tricyclic antidepressant drug amitriptyline and the anticonvulsant drug carbamazepine on the metabolism of the aliphatic-type phenothiazine neuroleptic levomepromazine in human liver. METHODS: The experiment was performed in vitro using human liver microsomes. The rates of levomepromazine 5-sulfoxidation and N-demethylation (levomepromazine concentrations: 5, 10, 25 and 50µM) were assessed in the absence and presence of amitriptyline or carbamazepine added in vitro (drug concentrations: 1, 2.5, 5, 10, 25µM). RESULTS: A kinetic analysis of levomepromazine metabolism carried out in the absence or presence of carbamazepine showed that the anticonvulsant drug potently inhibited levomepromazine 5-sulfoxidation (Ki=7.6µM, non-competitive inhibition), and moderately decreased the rate of levomepromazine N-demethylation (Ki=15.4µM, mixed inhibition) at therapeutic drug concentrations. On the other hand, amitriptyline weakly diminished the rate of levomepromazine 5-sulfoxidation (Ki=63µM, mixed inhibition) and N-demethylation (Ki=47.7µM, mixed inhibition). CONCLUSION: Regarding the central and peripheral effects of levomepromazine and some of its metabolites, the observed metabolic interaction between this neuroleptic and carbamazepine may be of pharmacological and clinical importance.

A naturalistic comparison study of the efficacy and safety of intramuscular olanzapine, intramuscular haloperidol, and intramuscular levomepromazine in acute agitated patients with schizophrenia.

OBJECTIVE: This study was a comparative investigation of the clinical efficacy and safety of intramuscular (IM) olanzapine, IM haloperidol, and IM levomepromazine in acute agitated patients with schizophrenia. METHODS: The subjects were 122 inpatients. Their clinical symptoms were assessed using Positive and Negative Syndrome Scale Excited Component (PANSS-EC), PANSS, and Agitation-Calmness Evaluation Scale, and their safety were assessed using the Abnormal Involuntary Movement Scale, Barnes Akathisia Rating Scale (BARS), and Drug-induced Extrapyramidal Symptoms Scale (DIEPSS). RESULTS: The mean changes from baseline on the PANSS-EC, Agitation-Calmness Evaluation Scale, Abnormal Involuntary Movement Scale, BARS, and DIEPSS scores were significantly better in both IM olanzapine and IM levomepromazine than in IM haloperidol. Of these, the mean changes from baseline on the BARS and DIEPSS scores were significantly better in IM olanzapine than in IM levomepromazine. The mean change from baseline on the PANSS positive score was significantly better in both IM olanzapine and IM haloperidol than in IM levomepromazine. CONCLUSIONS: The results of this study suggest the possibility that the anti-agitation effects of IM olanzapine and IM levomepromazine are more rapid than those of IM haloperidol. No worsening of EPS was observed. Our results also suggest that compared with IM levomepromazine, IM olanzapine is safer and affords greater improvement in symptoms.

Stability studies of binary and ternary mixtures containing morphine, midazolam, levomepromazine and hyoscine butylbromide for parenteral administration.

OBJECTIVES: [corrected] Parenteral (intravenous or subcutaneous) administration is routinely used in palliative medicine because patients are not able to take drugs orally. To avoid excessive injections, several drugs are usually given in the same dose, but the stability of these drugs when mixed is not always known. The aim of this study was to evaluate the stability of several mixtures of drugs (morphine, midazolam, levomepromazine and hyoscine butylbromide) kept under different storage conditions. METHODS: Stability was evaluated on the basis of percentage of drug remaining, pH, change of colour and gas or precipitate formation. KEY FINDINGS: The most notable results of the study showed that levomepromazine is rapidly degraded in 0.9% NaCl in all cases, and at high concentrations, morphine can precipitate when stored at 4°C. CONCLUSIONS: Mixtures containing levomepromazine are rapidly degraded under experimental conditions.

Incidence and causes for syringe driver site reactions in palliative care: A prospective hospice-based study.

BACKGROUND: Syringe drivers are routinely used in palliative care for the subcutaneous infusion of drugs for pain and symptom control. Local site reactions occurring at the site of infusion can lead to patient discomfort and the potential for sub-optimal symptom control. AIM: The aim of this study was to investigate whether there was a correlation between drugs administered subcutaneously via a syringe driver and the incidence of syringe driver site reactions, further linking this to time to syringe driver site reaction. DESIGN: Prospective quantitative data collection of syringe driver use for 170 hospice inpatients. SETTING/PARTICIPANTS: Specialist palliative care inpatient facility in the UK. Syringe driver recording forms were retrieved from case notes of consecutive patients who received medication via a syringe driver. RESULTS: An association between the presence of cyclizine and levomepromazine and the incidence of syringe driver site reactions was identified. A marked difference in incidence of syringe driver site reaction was observed between the two study centres (26.5% vs. 7.7%). Although baseline patient characteristics were comparable, a difference in practice between the centres was identified, i.e. use of parenteral cannulae. An association between the time a syringe driver was in situ and the occurrence of a syringe driver site reaction was also demonstrated. CONCLUSIONS: Recommendations can be made for the frequency of syringe driver site changes based on which drugs are in use. Incidental findings from the study have been used to change practice at the hospice study site, with regard to choice of parenteral cannulae.

A stability indicating assay for a combination of morphine sulphate with levomepromazine hydrochloride used in palliative care.

WHAT IS KNOWN AND OBJECTIVE: Morphine is used routinely in clinical practice to manage moderate to severe pain, whereas levomepromazine is commonly used at low doses to manage intractable nausea and vomiting. While it has been reported that an injection combination of morphine sulphate (0·5 mg/mL) and levomepromazine (0·1 mg/mL) was physically compatible, data on the chemical stability of combinations of these drugs has not been reported. Thus, a method was required for the assessment of the stability of morphine sulphate/levomepromazine hydrochloride combinations. METHODS: A high-performance liquid chromatography (HPLC) method was developed to assess the stability of the combinations. The injections were stored at 4 °C in the dark at room temperature under natural light and at 37 °C under artificial lighting. RESULTS AND DISCUSSION: Morphine sulphate was stable under all storage conditions, but the degree of degradation of levomepromazine hydrochloride increased as the storage temperature increased. The disappearance of levomepromazine hydrochloride was correlated with the appearance of a sulphoxide degradant. WHAT IS NEW CONCLUSION: The injection combinations of morphine sulphate and levomepromazine hydrochloride were shown in the current study to have a limited storage life with respect to their levomepromazine hydrochloride content.

Prescription persistence and safety of antipsychotic medication: a national registry-based 3-year follow-up.

PURPOSE: Long-term persistence of use, lack of co-prescribed anticholinergic antiparkinson drugs and low mortality may indicate effectiveness and safety of antipsychotic drugs. We aimed to assess 3-year prescription persistence, concomitant use of anticholinergics and mortality related to the use of all antipsychotic agents available in Norway. METHODS: Data were drawn from the Norwegian Prescription Database on the sales of antipsychotic and anticholinergic antiparkinson agents in 2004 to a total of 52,427 patients. The primary study group was a subgroup of 34,494 patients who were prescribed only one antipsychotic agent in 2004. The patients were re-investigated in 2007. For each of the 13 antipsychotic agents studied, assumed prescription persistence was assessed in light of use of anticholinergic antiparkinson agents in 2004, and casualty rates were noted. RESULTS: The highest persistence was demonstrated for zuclopenthixol (69.8%) and clozapine (88.4%). Zuclopenthixol was often co-prescribed with anticholinergics (22.2%), in contrast to clozapine (3.6%). Ziprasidone was associated with a low mortality (OR = 0.08), while chlorprotixene and haloperidol were associated with a high mortality (OR = 1.34 and 3.97, respectively) compared to levomepromazine. CONCLUSIONS: Clozapine demonstrated a high degree of continuity of prescription and a low level of concomitant use of anticholinergics. Zuclopenthixol also demonstrated a high degree of continuity of prescription, despite a considerable degree of co-prescribed anticholinergics. We did not find that any antipsychotic other than ziprasidone was associated with a low mortality. The use of haloperidol seemed to confer a mortality risk three times that of any of the other antipsychotic agents included.

O-demethylation of codeine to morphine inhibited by low-dose levomepromazine.

PURPOSE: Codeine/paracetamol (C/P) and levomepromazine (L) are frequently co-administered for the treatment of acute back pain, but the efficacy/effectiveness of this combination drug therapy has not been evaluated. The demethylation of codeine to morphine is catalyzed by the polymorphic enzyme cytochrome P450 2D6 (CYP2D6), of which levomepromazine (methotrimeprazine) is a known inhibitor. The aim of this study was to investigate whether low-dose levomepromazine inhibits the formation of morphine from codeine in a patient population of homozygous extensive (EM) and heterozygous extensive (HEM) metabolizers of CYP2D6. METHODS: Our patient cohort consisted of 29 patients hospitalized for acute back pain who were randomized to a 24-h treatment with either C/P (60 mg codeine + 1000 mg paracetamol) four times daily or to L+C/P (levomepromazine 5 + 5 + 5 + 10 mg + C/P) four times daily. After zero-urine sampling (baseline), the treatment was started and urine collected for 24 h. Blood samples were later genotyped for the CYP2D6*3, *4, and *6 polymorphisms by the PCR (LightCycler system) and for the *5 polymorphism using long PCR, to identify EM and HEM and to eliminate CYP2D6 poor metabolizers. Urine samples were analyzed using the CEDIA immunoassay and gas chromatography-mass spectrometry after enzymatic hydrolysis of glucuronide conjugates. O-demethylation ratios of codeine were calculated as hydrolyzed (total) concentrations of morphine/morphine + codeine. RESULTS: Twenty-two of the patients fulfilled the inclusion criteria, of whom ten were EM (five C/P and five L+C/P) and twelve were HEM (six C/P and six L+C/P) for functional CYP2D6 alleles. In the EM group, the median O-demethylation ratio was significantly higher (P = 0.016, Mann-Whitney test) after the C/P treatment (0.092, range 0.041-0.096) than after the L+C/P treatment (0.031, range 0.009-0.042). However, there was no significant difference between these two treatments in either the HEM group [n = 12; 0.024 (range 0.011-0.042) vs. 0.026 (range 0.009-0.041), respectively; P = 1.00] or in the combined EM/HEM group [11 C/P + 11 L+C/P; 0.041 (range 0.011-0.096) vs. 0.030 (range 0.009-0.042), respectively; P = 0.122]. CONCLUSIONS: Our study revealed significant inhibition in the O-demethylation of codeine to morphine in homozygous EM of CYP2D6 treated with low-dose levomepromazine and codeine/paracetamol, compared to treatment with codeine/paracetamol only. No significant difference could be detected in HEM or in the mixed and heterogenous group of EM/HEM. In patients prescribed this drug combination, the amount of morphine generated by the O-demethylation of codeine may be insufficient for effective pain relief. The therapeutic effect of codeine in the treatment of acute back pain should be assessed with and without levomepromazine.

Comparative study between target-controlled-infusion and continuous-infusion anesthesia in dogs treated with methotrimeprazine and treated with propofol and remifentanil.

PURPOSE: To compare two propofol infusion techniques in bitches subjected to ovary histerectomy by estimating the efficiency of the propofol target-dose, evaluating the cardiorespiratory and hemogasimetric attributes, and the bispectral scale index (BIS) as well as the recovery period characteristics. METHODS: Twenty anesthetized bitches were divided into two groups of 10 each (G1, G2). Animals of G1 were pre-treated with methotrimeprazine and anesthetized with target-controlled propofol infusion by means of a Harvard infusion pump combined to remifentanil through a syringe pump. RESULTS: Bradycardia and light hypotension, hemogasimetric and respiratory stability besides a good myorelaxation, more evident during continuous infusion and good hypnosis. CONCLUSIONS: Dosis used in both techniques, after methotrimeprazine pre-treatment and combined to the opioid, were efficient for the surgery. The target-controlled anesthesia required a smaller anesthetic consumption (propofol) with faster recovery periods.

Comparative study between target-controlled-infusion and continuous-infusion anesthesia in dogs treated with methotrimeprazine and treated with propofol and remifentanil

PURPOSE: To compare two propofol infusion techniques in bitches subjected to ovaryhisterectomy by estimating the efficiency of the propofol target-dose, evaluating the cardiorespiratory and hemogasimetric attributes, and the bispectral scale index (BIS) as well as the recovery period characteristics. METHODS: Twenty anesthetized bitches were divided into two groups of 10 each (G1, G2). Animals of G1 were pre-treated with methotrimeprazine and anesthetized with target-controlled propofol infusion by means of a Harvard infusion pump combined to remifentanil through a syringe pump. RESULTS: Bradycardia and light hypotension, hemogasimetric and respiratory stability besides a good myorelaxation, more evident during continuous infusion and good hypnosis. CONCLUSIONS: Dosis used in both techniques, after methotrimeprazine pre-treatment and combined to the opioid, were efficient for the surgery. The target-controlled anesthesia required a smaller anesthetic consumption (propofol) with faster recovery periods.

OBJETIVO: Comparar duas técnicas de infusão de propofol em cadelas submetidas à ovariohisterectomia, estudando a eficácia da dose alvo de propofol, avaliando os atributos cardiorrespiratórios, hemogasométricos e escala do índice bispectral, (BIS) bem como as características do período de recuperação. MÉTODOS: Foram anestesiadas 20 cadelas, distribuídos em dois grupos (GI e GII). Em GI, os animais foram pré-tratados com levomepromazina e anestesiados com propofol por infusão alvo controlada, através de bomba de infusão Harvard pump, associado com remifentanila, através de bomba de seringa. Em GII, os animais receberam o mesmo tratamento de GI, só que ao invés de receberem o propofol por infusão alvo controlada, receberam o propofol em infusão contínua de velocidade fixa. RESULTADOS: Bradicardia e discreta hipotensão, estabilidade hemogasométrica e respiratória, além de um bom miorrelaxamento, mais evidente na infusão contínua e boa hipnose. CONCLUSÕES: As doses de propofol utilizadas em ambas as técnicas, após o pré-tratamento de levomepromazina e associadas ao opióide, foram eficazes para a realização cirúrgica. A técnica de anestesia alvo controlada obteve um menor consumo de anestésico (propofol) com períodos mais rápidos de recuperação.

Role of selenium in heart lesions produced by neuroleptics in the rabbit.

Organic and/or functional heart lesions sometimes resulting in sudden death have been described in psychiatric patients treated with neuroleptics. As selenium has been suggested previously to play a role in the development of such lesions, the present study was undertaken to determine whether a correlation could be found between heart lesions induced by neuroleptics and changes in blood selenium as well as myocardial tissue concentrations in the rabbit. Twelve NZW adult rabbits were treated intramuscularly with both levomepromazine (3 mg kg(-1) day(-1)) and risperidone (1 mg kg(-1) once every other week) for 3 months, and compared with 12 saline-treated controls. Blood samples were drawn before and at the end of the study. Tissue samples from the heart, liver and kidneys were obtained at the end of treatment, and the hearts were examined histologically. Heart lesions including disorganization of cardiac fibers, myolysis, interstitial and endocardial fibrosis, and necrosis were noted in treated animals, but not in controls. There was a 20% decrease in selenium blood levels and a 50% decrease in selenium myocardial tissue levels in treated animals compared with controls (P < 0.001). In contrast, no differences in selenium levels in liver and kidneys were found across the experimental groups. These results suggest a possible correlation between selenium depletion and neuroleptics-induced heart lesions.

Continuous infusion in adult females dogs submitted to ovariohysterectomy with midazolam-xylazine and/or medetomidine pre-treated with methotrimeprazine and buprenorphine

PURPOSE: To compare, by continuous infusion of ketamine or medetomidine combined to methotrimeprazine and buprenorphine, ketamine and midazolam, the degree of hypnosis, myorelaxation, anesthetic quality and surgical feasibility through evaluation of possible parametric alterations and recovery quality. METHODS: 20 healthy adult females dogs, aged 3 to 5 years, body weight between 7 and 15 kg, were assigned randomly and homogenously to 2 groups of 10 animals each (n=10), group 1 (G1) and group 2 (G2), respectively. Animals of G1 were subjected to a pre-treatment with intravenous 1.0 mg/kg methotrimeprazine and or 3ì/kg. After 15 minutes, a 5.0 mg/kg ketamine and 0.2 mg/kg midazolam were intravenously injected. Immediately after induction, an anesthetic combination of 0.4 mg/kg/h midazolam, 20 mg/kg/h ketamine and 1.0 mg/kg/h xylazine, was continuously and intravenously administered for 30 minutes. The same techniques were used in G2 except for the substitution of xylazine for 30ìg/kg/h medetomidine. RESULTS: In G1 there was a 1st and 2nd degree atrioventricular heart block, a longer recovery period and lower quality. In G2 a 1st degree atrioventricular heart block occurred but isolated and ephemeral. CONCLUSIONS: The continuous infusion method, besides reducing drugs utilization, prevented collateral effects allowing a more tranquil recovery with no excitations, both protocols permitted the surgical procedure (ovary-hysterectomy) bringing about a reduction in hypnosis and an accentuated myorelaxation. Xylazine and medetomidine showed a similar pharmacodynamic behavior but with different clinical aspects. The electrocardiographic alterations observed in G2 and in a lower degree in G1 must be well studied. Describers: dogs, ketamine, methotrimeprazine, medetomidine, midazolam and xylazine.

OBJETIVO: Comparar através de infusão contínua de xilazina ou medetomidina associada à metotrimeprazina e buprenorfina, cetamina e midazolam, o grau de hipnose, miorrelaxamento e qualidade anestésica e a viabilidade cirúrgica, avaliando eventuais alterações paramétricas e qualidade de recuperação. MÉTODOS: Foram utilizados 20 cães fêmeas, adultas, hígidas (3 a 5 anos de idade) com peso corporal entre 7 e 15 quilos, escolhidas e distribuídas aleatoriamente de forma homogênea em 2 grupos de 10 animais cada, (n=10) sendo estes designados por Grupo 1 (G1), e Grupo 2 (G 2). Em G1, os animais foram submetidos a um pré-tratamento com metotrimeprazina na dose de 1,0 mg/kg e buprenorfina na dose de 0,003mg/kg ou 3 µg/kg intravenoso. Decorridos 15 minutos, administrou-se cetamina na dose de 5,0 mg/kg e midazolam na dose de 0,2 mg/kg intravenoso. Imediatamente após a indução iniciou-se administração contínua, por um período de 30 minutos, da associação anestésica de midazolam 0,4 mg/kg/h, cetamina 20mg/kg/h e xilazina 1,0 mg/kg/h IV. Em G 2 utilizou-se a mesma técnica empregada em G1 substituindo-se, a xilazina pela medetomidina na dose de 30µg/kg/h. RESULTADOS: Verificou-se em G1 bloqueio átrio-ventricular de primeiro e segundo grau, período de recuperação mais longo além de menor qualidade. Em G 2 observou-se bloqueio átrio-ventricular de primeiro grau isolado e de ação fugaz. CONCLUSÕES: Ao se aplicar o método de infusão contínua, além da redução dos fármacos aplicados, evitaram-se efeitos colaterais permitindo uma recuperação mais tranqüila e isenta de excitações, ambos os protocolos permitiram a realização do ato cirúrgico (ovário-salpingo-histerectomia), causando uma redução da hipnose e um miorrelaxamento acentuado. A xilazina e a medetomidina apresentam um comportamento farmacodinâmico semelhante, porém com aspectos clínicos diferentes, as alterações eletrocardiográficas observadas em G 2 e em menor grau em G1 devem ser melhor estudadas.

Continuous infusion in adult females dogs submitted to ovariohysterectomy with midazolam-xylazine and/or medetomidine pre-treated with methotrimeprazine and buprenorphine.

PURPOSE: To compare, by continuous infusion of ketamine or medetomidine combined to methotrimeprazine and buprenorphine, ketamine and midazolam, the degree of hypnosis, myorelaxation, anesthetic quality and surgical feasibility through evaluation of possible parametric alterations and recovery quality. METHODS: 20 healthy adult females dogs, aged 3 to 5 years, body weight between 7 and 15 kg, were assigned randomly and homogenously to 2 groups of 10 animals each (n=10), group 1 (G1) and group 2 (G2), respectively. Animals of G1 were subjected to a pre-treatment with intravenous 1.0 mg/kg methotrimeprazine and or 3ì/kg. After 15 minutes, a 5.0 mg/kg ketamine and 0.2 mg/kg midazolam were intravenously injected. Immediately after induction, an anesthetic combination of 0.4 mg/kg/h midazolam, 20 mg/kg/h ketamine and 1.0 mg/kg/h xylazine, was continuously and intravenously administered for 30 minutes. The same techniques were used in G2 except for the substitution of xylazine for 30ìg/kg/h medetomidine. RESULTS: In G1 there was a 1st and 2nd degree atrioventricular heart block, a longer recovery period and lower quality. In G2 a 1st degree atrioventricular heart block occurred but isolated and ephemeral. CONCLUSIONS: The continuous infusion method, besides reducing drugs utilization, prevented collateral effects allowing a more tranquil recovery with no excitations, both protocols permitted the surgical procedure (ovary-hysterectomy) bringing about a reduction in hypnosis and an accentuated myorelaxation. Xylazine and medetomidine showed a similar pharmacodynamic behavior but with different clinical aspects. The electrocardiographic alterations observed in G2 and in a lower degree in G1 must be well studied. Describers: dogs, ketamine, methotrimeprazine, medetomidine, midazolam and xylazine.

Parametric evaluation of methotrimeprazine-midazolam-ketamine and methotrimeprazine-midazolam-ketamine-xylazine combination in dogs.

PURPOSE: To evaluate the parameters of dogs anesthetized by different dissociative drugs protocols through continuous intravenous infusion. METHODS: Thirty healthy dogs of both sexes were assigned randomly to three groups (G1, G2, and G3). G1 was administered with methotrimeprazine as a pre-anesthetic medication, intravenously midazolam-ketamine as bolus for induction and midazolam-ketamine by continuous intravenous infusion for a 60 minute-period of maintenance. G2: the same as for G1. plus an increase in the midazolam dose during maintenance. G3: the same treatment as for G2, plus the addition of xylazine during maintenance. Immediately after induction the anesthetic maintenance started, and measures were taken 15 minutes after pre-medication, at 10 minutes intervals, during maintenance (M0 to M7). RESULTS: Bradycardia, atrioventricular blockage, bradypnea and hypoxemia were shown in G3. G1 and G2 showed a slight hypotension only. CONCLUSION: There were some advantages by using the continuous intravenous via: no parameters oscillation and reduction in the anesthetic recovery period. The increase in midazolam dose brought about little parametric variations which were greater when xylazine was used, with a consequent hypoxemia, bradyarrhytmia, and decrease in respiratory frequency and minute volume.