Propofol-ketamine versus dexmedetomidine-ketamine for sedation during upper gastrointestinal endoscopy in pediatric patients: a randomized clinical trial / Propofol­cetamina versus dexmedetomidina­cetamina para sedação durante endoscopia digestiva alta em pacientes pediátricos: estudo clínico randomizado

Abstract Background and objectives Day-case pediatric sedation is challenging. Dexmedetomidine is a sedative analgesic that does not induce respiratory depression. We compared dexmedetomidine to propofol when it was added to ketamine for sedation during pediatric endoscopy, regarding recovery time and hemodynamic changes. Methods We enrolled 120 patients (2−7 years in age) and randomly assigned them into two groups. Each patient received intravenous (IV) ketamine at a dose of 1 mg.kg-1 in addition to either propofol (1 mg.kg-1) or dexmedetomidine (0.5 µg.kg-1). The recovery time was compared. Hemodynamics, oxygen saturation, need for additional doses, postoperative complications and endoscopist satisfaction were monitored. Results There was no significant difference in hemodynamics between the groups. The Propofol-Ketamine (P-K) group showed significantly shorter recovery times than the Dexmedetomidine-Ketamine (D-K) group (21.25 and 29.75 minutes, respectively, p < 0.001). The P-K group showed more oxygen desaturation. Eleven and 6 patients experienced SpO2 < 92% in groups P-K and D-K, respectively. A significant difference was noted regarding the need for additional doses; 10% of patients in the D-K group needed one extra dose, and 5% needed two extra doses, compared to 25% and 20% in the P-K group, respectively (p = 0.001). The P-K group showed less post-procedure nausea and vomiting. No statistically significant difference between both groups regarding endoscopist satisfaction. Conclusions The P-K combination was associated with a shorter recovery time in pediatric upper gastrointestinal endoscopy, while the D-K combination showed less need for additional doses. Registration number Clinical trials.gov (NCT02863861).

Resumo Justificativa e objetivos A sedação ambulatorial pediátrica é um desafio. A dexmedetomidina é um analgésico sedativo que não induz à depressão respiratória. Comparamos a dexmedetomidina ao propofol quando associados à cetamina para sedação durante endoscopia pediátrica, quanto ao tempo de recuperação e às alterações hemodinâmicas. Métodos Foram recrutados 120 pacientes (2−7 anos de idade) que foram aleatoriamente alocados em dois grupos. Cada paciente recebeu cetamina IV na dose de 1 mg.kg‐1, além de propofol (1 mg.kg‐1) ou dexmedetomidina (0,5 µg.kg‐1). Comparamos o tempo de recuperação. A hemodinâmica, saturação de oxigênio, necessidade de doses adicionais, complicações pós‐operatórias e satisfação do endoscopista foram monitoradas. Resultados Não houve diferença significante entre os grupos no que diz respeito à hemodinâmica. O grupo Propofol‐Cetamina (P‐C) apresentou tempos de recuperação significantemente mais curtos do que o grupo Dexmedetomidina‐Cetamina (D‐C) (21,25 e 29,75 minutos respectivamente, p < 0,001). Observou‐se frequência maior de dessaturação de oxigênio no grupo P‐C. Onze e 6 pacientes apresentaram SpO2 < 92% nos grupos P‐C e D‐C, respectivamente. Uma diferença significante foi observada em relação à necessidade de doses adicionais; 10% dos pacientes no grupo D‐C precisaram de uma dose extra e 5% precisaram de duas doses extras, em comparação com 25% e 20% no grupo P‐C, respectivamente (p = 0,001). O grupo P‐C apresentou menos náuseas e vômitos após o procedimento. Não houve diferença estatisticamente significante entre os dois grupos em relação à satisfação do endoscopista. Conclusões A combinação P‐C foi associada a tempo mais curto de recuperação na endoscopia digestiva alta pediátrica, enquanto a combinação D‐C mostrou menor necessidade de doses adicionais. Número de registro Clinical trials.gov (NCT02863861).

Intoxicación por ácido acetilsalicílico, fisiopatología y manejo / Physiopathology and management of acetylsalicylic acid intoxication

Acetylsalicylic acid (ASA) intoxication is potentially lethal. After ingestion, AAS is rapidly transformed into salicylic acid that dissociates into an hydrogen ion plus salicylate. Salicylate is the main form of AAS in the body and produces multiple alterations. Initially, the stimulation of the ventilatory center promotes a respiratory alkalosis. Then, the mitochondrial dysfunction induced by salicylate, will generate a progressive metabolic acidosis due to the accumulation of ketoacids, lactic acid and dicarboxylic acids among others. Another alterations include hydro electrolytic disorders, gastrointestinal lesions, neurological involvement, ototoxicity and coagulopathy. The correct handling of acetylsalicylic acid intoxication requires an thorough knowledge of its pharmacokinetics and pharmacodynamics. Treatment consists in life support measures, gastric lavage, activated charcoal and urinary alkalization to promote the excretion of salicylates. In some occasions, it will be necessary to start renal replacement therapy as soon as possible.

Acute but not chronic metabolic acidosis potentiates the acetylcholine-induced reduction in blood pressure: an endothelium-dependent effect

Metabolic acidosis has profound effects on vascular tone. This study investigated the in vivo effects of acute metabolic acidosis (AMA) and chronic metabolic acidosis (CMA) on hemodynamic parameters and endothelial function. CMA was induced by ad libitum intake of 1% NH4Cl for 7 days, and AMA was induced by a 3-h infusion of 6 M NH4Cl (1 mL/kg, diluted 1:10). Phenylephrine (Phe) and acetylcholine (Ach) dose-response curves were performed by venous infusion with simultaneous venous and arterial blood pressure monitoring. Plasma nitrite/nitrate (NOx) was measured by chemiluminescence. The CMA group had a blood pH of 7.15±0.03, which was associated with reduced bicarbonate (13.8±0.98 mmol/L) and no change in the partial pressure of arterial carbon dioxide (PaCO2). The AMA group had a pH of 7.20±0.01, which was associated with decreases in bicarbonate (10.8±0.54 mmol/L) and PaCO2 (47.8±2.54 to 23.2±0.74 mmHg) and accompanied by hyperventilation. Phe or ACh infusion did not affect arterial or venous blood pressure in the CMA group. However, the ACh infusion decreased the arterial blood pressure (ΔBP: -28.0±2.35 mm Hg [AMA] to -4.5±2.89 mmHg [control]) in the AMA group. Plasma NOx was normal after CMA but increased after AMA (25.3±0.88 to 31.3±0.54 μM). These results indicate that AMA, but not CMA, potentiated the Ach-induced decrease in blood pressure and led to an increase in plasma NOx, reinforcing the effect of pH imbalance on vascular tone and blood pressure control.

Comparison of the effects of magnesium sulphate and dexmedetomidine on surgical vision quality in endoscopic sinus surgery: randomized clinical study / Comparação dos efeitos de sulfato de magnésio e da dexmedetomidina sobre a qualidade da visibilidade em cirurgia endoscópica sinusal: estudo clínico randomizado / Comparación de los efectos de sulfato de magnesio y dexmedetomidina sobre la calidad de la visibilidad en cirugía endoscópica sinusal: estudio clínico aleatorizado

Background and objectives: Even a small amount of bleeding during endoscopic sinus surgery can corrupt the endoscopic field and complicate the procedure. Various techniques, including induced hypotension, can minimize bleeding during endoscopic sinus surgery. The aim of this study was to compare the surgical vision quality, haemodynamic parameters, postoperative pain, and other effects of magnesium, a hypotensive agent, with that of dexmedetomidine, which was initially developed for short-term sedation in the intensive care unit but also is an alpha 2 agonist sedative. Method: 60 patients between the ages of 18 and 45 years were divided into either the magnesium group (Group M) or the dexmedetomidine group (Group D). In Group M, magnesium sulphate was given at a pre-induction loading dose of 50 mg kg−1 over 10 min and maintained at 15 mg kg−1 h−1; in Group D, dexmedetomidine was given at 1 mcg kg−1 10 min before induction and maintained at 0.6 mcg kg−1 h−1. Intraoperatively, the haemodynamic and respiratory parameters and 6-point intraoperative surgical field evaluation scale were recorded. During the postoperative period, an 11-point numerical pain scale, the Ramsay sedation scale, the nausea/vomiting scale, the adverse effects profile, and itching parameters were noted. Results: Group D showed a significant decrease in intraoperative surgical field evaluation scale scale score and heart rate. The average operation time was 50 min, and Group M had a higher number of prolonged surgeries. No significant difference was found in the other parameters. Conclusions: Due to its reduction of bleeding and heart rate in endoscopic sinus surgery and its positive impacts on the duration of surgery, we consider dexmedetomidine to be a good alternative to magnesium. .

Justificativa e objetivo: Uma quantidade, mesmo pequena, de sangramento durante a cirurgia endoscópica pode alterar o campo endoscópico e dificultar o procedimento. Várias técnicas, incluindo hipotensão induzida, podem minimizar o sangramento durante a cirurgia endoscópica. O objetivo deste estudo foi comparar a qualidade da visibilidade cirúrgica, os parâmetros hemodinâmicos, a dor no período pós-operatório e outros efeitos do sulfato de magnésio, um agente hipotensor, com os da dexmedetomidina, inicialmente desenvolvida para sedação em curto prazo em unidade de terapia intensiva, mas que também é um sedativo agonista alfa-2. Métodos: Foram alocados 60 pacientes entre 18 e 45 anos em dois grupos: Grupo M (magnésio) e Grupo D (dexmedetomidina). No Grupo M, sulfato de magnésio foi administrado pré-indução a uma dose de carga de 50 mg kg−1 por 10 minutos e mantida com 15 mg kg−1 h−1; no Grupo D, dexmedetomidina foi administrada a uma dose de 1 mcg kg−1 10 minutos antes da indução e mantida com 0,6 mcg kg−1 h−1. No período intraoperatório, foram registrados os parâmetros hemodinâmicos e respiratórios e a avaliação do campo cirúrgico com uma escala de seis pontos. Durante o período pós-operatório foram registrados os valores da escala numérica de 11 pontos para avaliar a dor, a escala de sedação de Ramsay, a escala de avaliação de náusea/vômito, o perfil dos efeitos adversos e pruridos. Resultados: O Grupo D apresentou redução significativa da frequência cardíaca e do escore na escala de avaliação do campo cirúrgico intraoperatório. A média do tempo cirúrgico foi de 50 minutos e o Grupo M apresentou um número maior de cirurgias prolongadas. ...

Introducción y objetivo: Una cantidad, aunque sea pequeña, de sangrado durante la cirugía endoscópica puede alterar el campo endoscópico y dificultar el procedimiento. Varias técnicas que incluyen hipotensión inducida pueden minimizar el sangrado durante la cirugía endoscópica. El objetivo de este estudio fue comparar la calidad de la visibilidad quirúrgica, los parámetros hemodinámicos, el dolor en el período postoperatorio y otros efectos del sulfato de magnesio, que es un agente hipotensor, con los de la dexmedetomidina, inicialmente desarrollada para la sedación a corto plazo en la unidad de cuidados intensivos, pero que también es un sedante agonista alfa-2. Método: 60 pacientes con edades entre 18 y 45 años se dividieron en 2 grupos: grupo M (magnesio) y grupo D (dexmedetomidina). En el grupo M, el sulfato de magnesio fue administrado antes de la inducción en dosis de carga de 50 mg kg−1 por 10 min y se mantuvo con 15 mg kg−1 h−1; en el grupo D, la dexmedetomidina fue administrada con una dosis de 1 µg kg−1 durante 10 min antes de la inducción y se mantuvo con 0,6 µg kg−1 h−1. En el período intraoperatorio se registraron los parámetros hemodinámicos y respiratorios y la evaluación del campo quirúrgico con una escala de 6 puntos. Durante el postoperatorio también se registraron la escala numérica de 11 puntos para evaluar el dolor, la escala de sedación de Ramsay, la escala de evaluación de náuseas/vómito, el perfil de los efectos adversos y los pruritos. Resultados: El grupo D tuvo una reducción significativa de la frecuencia cardíaca y de la puntuación en la escala de evaluación del campo quirúrgico intraoperatorio. La media del tiempo quirúrgico fue de 50 min, y el grupo M tuvo un número mayor de ...

Efeito da administração de solução salina na estabilidade da circulação durante a indução de anestesia geral com propofol em estudo randômico e controlado de procedimentos ginecológicos / Effect of normal saline administration on circulation stability during general anesthesia induction with propofol in gynecological procedures - randomised-controlled study / Efecto de la administración de solución salina normal en la estabilidad de la circulación durante la inducción de anestesia general con propofol en estudio aleatorio y controlado de procedimientos ginecológicos

JUSTIFICATIVA E OBJETIVO: Comparar o efeito da administração profilática de solução salina normal com o efeito hipotensor de propofol em pacientes do sexo feminino programadas para procedimentos ginecológicos. MÉTODO: Foram randomicamente alocadas em dois grupos 69 pacientes, ASA I-II. O Grupo 1 recebeu 5 mL.kg-1 de solução salina a 0,9% 10 minutos antes da indução e o Grupo 2 não recebeu nada (controle). A anestesia foi induzida com propofol e fentanil e depois mantida com propofol e remifentanil. As variáveis hemodinâmicas foram mensuradas pré- e pós-indução da anestesia geral. RESULTADOS: Após a indução, ambos os grupos apresentaram queda significativa da pressão arterial média (p < 0,001) e redução também significativa da frequência cardíaca (p < 0,02 no grupo de estudo e p < 0,001 no grupo de controle). A pressão arterial média pré-indução teve uma queda de mais de 25% em 35% dos pacientes do grupo controle em comparação com apenas 17% dos pacientes que receberam a solução salina (p < 0,04). CONCLUSÃO: A administração profilática de solução salina pode diminuir a porcentagem de pacientes que apresentam queda significativa da pressão arterial após a indução de propofol em anestesia geral.

BACKGROUND AND OBJECTIVE: To compare the effect of prophylactic administration of normal saline against the hypotensive effect of propofol in female patients booked for gynecological procedures. METHOD: Sixty nine ASA (I, II) patients were randomly allocated into two groups, group 1 received 5 mL.kg-1 of 0.9% normal saline 10 minutes before induction, whereas group 2 received nothing (control). Anesthesia was induced with propofol and fentanyl then maintained with propofol and remifentanil. We measured hemodynamic variables pre and post general anesthesia induction. RESULTS: Both groups had significant drops in post induction mean arterial blood pressure (P < 0.001). Also both groups had significant drops in post induction heart rate ((P < 0.02 in sample group and P < 0.001 in control group), and 35% of patients in the control group had more than 25% drop in the pre induction mean arterial blood pressure, compared with only 17% of patients in the saline group (P < 0.04). CONCLUSION: The prophylactic administration of normal saline could decrease the percentage of patients who had a significant drop in their blood pressure after propofol induction of general anesthesia.

JUSTIFICATIVA Y OBJETIVO: Comparar el efecto de la administración profiláctica de solución salina normal con el efecto hipotensor de propofol en pacientes del sexo femenino programadas para procedimientos ginecológicos. MÉTODO: Sesenta y nueve pacientes con ASA I-II fueron ubicados aleatoriamente en dos grupos. El Grupo 1 recibió 5 mL.kg-1 de solución salina al 0,9% 10 minutos antes de la inducción y el Grupo 2 no recibió nada. La anestesia fue inducida con propofol y fentanilo y después se mantuvo con propofol y remifentanilo. Las variables hemodinámicas fueron mensuradas antes y después de la inducción de la anestesia general. RESULTADOS: Después de la inducción, ambos grupos presentaron una caída significativa de la presión arterial promedio (p < 0,001) y una reducción también significativa de la frecuencia cardíaca (p < 0,02 en el grupo de estudio y p < 0,001 en el grupo de control). La presión arterial promedio pre inducción tuvo una caída de más del 25% en 35% de los pacientes del grupo control en comparación con solamente un 17% de los pacientes que recibieron la solución salina (p < 0,04). CONCLUSIÓN: La administración profiláctica de la solución salina normal puede disminuir el porcentaje de pacientes que presentan una caída significativa de la presión arterial después de la inducción de propofol en la anestesia general.

Sildenafil vs. Nitroprussiato de Sódio durante Teste de Reatividade Pulmonar pré-transplante cardíaco / Sildenafil vs. sodium before nitroprusside for the pulmonary hypertension reversibility test before cardiac transplantation

FUNDAMENTO: A hipertensão pulmonar é associada ao pior prognóstico no pós-transplante cardíaco. O teste de reatividade pulmonar com Nitroprussiato de Sódio (NPS) está associado a elevados índices de hipotensão arterial sistêmica, disfunção ventricular do enxerto transplantado e elevadas taxas de desqualificação para o transplante. OBJETIVO: Neste estudo, objetivou-se comparar os efeitos do Sildenafil (SIL) e NPS sobre variáveis hemodinâmicas, neuro-hormonais e ecocardiográficas durante teste de reatividade pulmonar. MÉTODOS: Os pacientes foram submetidos, simultaneamente, ao cateterismo cardíaco direito, ao ecocardiograma e à dosagem de BNP e gasometria venosa, antes e após administração de NPS (1 - 2 µg/Kg/min) ou SIL (100 mg, dose única). RESULTADOS: Ambos reduziram a hipertensão pulmonar, porém o nitrato promoveu hipotensão sistêmica significativa (Pressão Arterial Média - PAM: 85,2 vs. 69,8 mmHg, p < 0,001). Ambos reduziram as dimensões cardíacas e melhoraram a função cardíaca esquerda (NPS: 23,5 vs. 24,8 %, p = 0,02; SIL: 23,8 vs. 26 %, p < 0,001) e direita (SIL: 6,57 ± 2,08 vs. 8,11 ± 1,81 cm/s, p = 0,002; NPS: 6,64 ± 1,51 vs. 7,72 ± 1,44 cm/s, p = 0,003), medidas pela fração de ejeção ventricular esquerda e Doppler tecidual, respectivamente. O SIL, ao contrário do NPS, apresentou melhora no índice de saturação venosa de oxigênio, medido pela gasometria venosa. CONCLUSÃO: Sildenafil e NPS são vasodilatadores que reduzem, de forma significativa, a hipertensão pulmonar e a geometria cardíaca, além de melhorar a função biventricular. O NPS, ao contrário do SIL, esteve associado a hipotensão arterial sistêmica e piora da saturação venosa de oxigênio.

BACKGROUND: Pulmonary hypertension is associated with a worse prognosis after cardiac transplantation. The pulmonary hypertension reversibility test with sodium nitroprusside (SNP) is associated with a high rate of systemic arterial hypotension, ventricular dysfunction of the transplanted graft and high rates of disqualification from transplantation. OBJECTIVE: This study was aimed at comparing the effects of sildenafil (SIL) and SNP on hemodynamic, neurohormonal and echocardiographic variables during the pulmonary reversibility test. METHODS: The patients underwent simultaneously right cardiac catheterization, echocardiography, BNP measurement, and venous blood gas analysis before and after receiving either SNP (1 - 2 µg/kg/min) or SIL (100 mg, single dose). RESULTS: Both drugs reduced pulmonary hypertension, but SNP caused a significant systemic hypotension (mean blood pressure - MBP: 85.2 vs. 69.8 mm Hg; p < 0.001). Both drugs reduced cardiac dimensions and improved left cardiac function (SNP: 23.5 vs. 24.8%, p = 0.02; SIL: 23.8 vs. 26%, p < 0.001) and right cardiac function (SIL: 6.57 ± 2.08 vs. 8.11 ± 1.81 cm/s, p = 0.002; SNP: 6.64 ± 1.51 vs. 7.72 ± 1.44 cm/s, p = 0.003), measured through left ventricular ejection fraction and tissue Doppler, respectively. Sildenafil, contrary to SNP, improved venous oxygen saturation, measured on venous blood gas analysis. CONCLUSION: Sildenafil and SNP are vasodilators that significantly reduce pulmonary hypertension and cardiac geometry, in addition to improving biventricular function. Sodium nitroprusside, contrary to SIL, was associated with systemic arterial hypotension and worsening of venous oxygen saturation.

The Effects of Intravenous Ephedrine During Spinal Anesthesia for Cesarean Delivery: A Randomized Controlled Trial

We designed a randomized, double-blinded study to determine the efficacy and safety of 0.5 mg/kg intravenous ephedrine for the prevention of hypotension during spinal anesthesia for cesarean delivery. Patients were randomly allocated into two groups: ephedrine group (n=21) and control group (n=21). Intravenous preload of 15 mL/kg lactated Ringer's solution was given. Shortly after the spinal injection, ephedrine 0.5 mg/kg or saline was injected intravenous for 60 sec. The mean of highest and lowest heart rate in the ephedrine group was higher than those of control group (P<0.05). There were significant lower incidences of hypotension and nausea and vomiting in the ephedrine group compared with the control group (8 [38.1%] vs. 18 [85.7%]); (4 [19%] vs. 12 [57.1%], respectively) (P<0.05). The first rescue ephedrine time in the ephedrine group was significantly longer (14.9+/-7.1 min vs. 7.9+/-5.4 min) than that of the control group (P<0.05). Neonatal outcome were similar between the study groups. These findings suggest, the prophylactic bolus dose of 0.5 mg/kg intravenous ephedrine given at the time of intrathecal block after a crystalloid fluid preload, plus rescue boluses reduce the incidence of hypotension.

Letter to the Editor: Hypotension after Etomidate Use in Sepsis

No abstract available.

Prospective study of hypotension after spinal anesthesia for cesarean section at Siriraj Hospital: incidence and risk factors, Part 2.

BACKGROUND: The incidence of hypotension after spinal anesthesia is highest in cesarean section. The authors' first retrospective study identified three risk factors that included two non-modifiable (patient's height and low baseline systolic blood pressure) and one modifiable risk factor (sensory analgesia equal to or higher than TS) associated with hypotension. OBJECTIVE: To create a prospective record of the event in the patients who received successful spinal anesthesia for cesarean section. MATERIAL AND METHOD: A prospective data collection, together with questionnaires that were completed by the responsible anesthetic team at the end of the operation for each consecutive patient. All parameters were coded and recorded in SPSS11.5. To assess the association between two categorical variables in a univariable analysis, chi-square test was used along with odds ratio (OR) and its 95% confidence interval (CI). Mutivariable analysis via multiple logistic regressions was employed to determine the effect of each independent variable. RESULTS: Eight hundred and seven full-term pregnant women received successful spinal anesthesia for cesarean section at Siriraj Hospital from July 1 to December 31, 2004. Hypotension was defined as lowest systolic < 100 mmHg and the pressure was lower to equal to or more than 20% of baseline. Incidence of hypotension was 65.1%. Age > 35 yr BMI > 35 were two non-modifiable risk factors that increased the incidence of hypotension in the crude odds ratio (OR) 1.62 and 2.83 respectively with narrow 95% confidence interval. The level of sensory analgesia equal to or higher than T5 was the only one modifiable risk factor that increased the incidence of hypotension with crude OR 1.55 and narrow 95% CI. CONCLUSION: Limitation of the dose of local anesthetic agent or addition of some opioids could reduce the incidence and severity of hypotension after spinal anesthesia for cesarean section.

Prevention of hypotension during propofol induction: a comparison of preloading with 3.5% polymers of degraded gelatin (Haemaccel) and intravenous ephedrine.

The present study compared the efficacy of preloading with colloid "Haemaccel" with vasoconstrictor (intravenous ephedrine sulphate) in preventing hypotension during propofol induction. This prospective, randomized study included 120 patients of Amercan Society of Anaesthesiologists (ASA) physical status I and II ageing 21 to 50 years of both gender coming for routine surgery. Patients were randomly allocated into three groups with 40 patients in each. Group A (control) did not receive any study medication, group B received Haemaccel (10 ml/kg intravenously over 10-15 minutes) and group C received injection ephedrine (0.2 mg/kg iv) prior to induction of anaesthesia. Propofol (2.5 mg/kg iv) was used for induction of anaesthesia. Heart rate and blood pressure were recorded before induction (baseline) and then every minute for 5 minutes after administering propofol. Anaesthesia was continued with standard technique thereafter. Hypotension was defined as fall in systolic blood pressure more than 20% from the basal value. The incidence of hypotension in Haemaccel (23.1%) or ephedrine group (22.5%) was significantly less than the control group (67.5%, P<0.01). We conclude that though preloading with colloid (Haemaccel) or prior injection of sympathomimetic (ephedrine) are not fully efficacious in preventing hypotension caused by propofol induction, both decrease the incidence in significant number of patients with heart rate less than baseline value in the colloid group.

Labor analgesia with ropivacaine added to clonidine: a randomized clinical trial / Analgesia de parto com ropivacaína associada à clonidina: pesquisa clínica randomizada

CONTEXT AND OBJECTIVE: Previous studies have led to speculation that the association between ropivacaine and clonidine might be more effective than ropivacaine alone. We examined the maternal-fetal effects of two pharmacological approaches: a low dose of ropivacaine or a lower dose of ropivacaine plus clonidine for epidural analgesia during labor. DESIGN AND SETTING: Prospective study at Department of Anesthesiology, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista. METHODS: Thirty-two pregnant women in American Society of Anesthesiologists physical status I and II randomly underwent epidural analgesia using 15 ml of ropivacaine 0.125 percent (R group) or 15 ml of ropivacaine 0.0625 percent plus 75 µg clonidine (RC group). Pain intensity, sensory block level, latency time, motor block intensity, duration of labor analgesia and duration of epidural analgesia were evaluated. The newborns were evaluated using Apgar scores and the Amiel-Tison method (neurological and adaptive capacity score). RESULTS: There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75 percent of the RC group newborns were found to be neurologically healthy at the 24-hour examination. RESULTS: There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75 percent of the RC group newborns were found to be neurologically healthy...

CONTEXTO E OBJETIVO: A associação entre ropivacaína e clonidina agiria menos que a ropivacaína isolada na mãe e no feto? Foram pesquisados os efeitos materno-fetais de duas técnicas farmacológicas: pequena dose de ropivacaína ou dose menor de ropivacaína mais clonidina na analgesia peridural para parto. TIPO DE ESTUDO E LOCAL: Estudo prospectivo, Departamento de Anestesiologia, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista. MÉTODOS: Trinta e duas parturientes, estado físico de acordo com a American Society of Anesthesiologists I e II, foram aleatoriamente submetidas à analgesia peridural com 15 ml de ropivacaína 0,125 por cento (grupo R) ou 15 ml de ropivacaína 0,0625 por cento mais clonidina, 75 µg (grupo RC). Foram avaliados: intensidade da dor, nível do bloqueio sensitivo, latência, intensidade do bloqueio motor, duração da analgesia de parto e da analgesia peridural. Os neonatos foram avaliados pelo Apgar e método de Amiel-Tison (capacidade neurológica e adaptativa). RESULTADOS: Não houve diferenças significativas entre grupos para dor, nível de bloqueio sensitivo, duração da analgesia peridural e Apgar. Para latência, duração da analgesia de parto e bloqueio motor, grupo R < grupo RC. O escore da capacidade neurológica e adaptativa de meia e duas horas foi maior para o grupo R. Cem por cento dos neonatos do grupo R e 75 por cento dos do grupo RC estavam neurologicamente saudáveis ao exame de 24 horas. CONCLUSÃO: Pequena dose de ropivacaína e dose menor mais clonidina aliviaram a dor materna durante o parto. Neonatos de mães que receberam apenas ropivacaína mostraram melhores escores da capacidade neurológica e adaptativa.

Incidence and risk factors of hypotension and bradycardia after spinal anesthesia for cesarean section.

BACKGROUND: Hypotension or bradycardia after spinal anesthesia for cesarean section remain common and are serious complications. The current study evaluated factors associated to the incidences of hypotension or bradycardia in this context. MATERIAL AND METHOD: A prospective cross sectional study from November 1, 2004 to July 31, 2005 was conducted on 722 parturients undergoing cesarean section under spinal anesthesia. T-test and Chi-square test were used in univariate analysis to compare continuous data and categorical data respectively. Multivariate logistic regression was performed on the variables hypotension (systolic pressure decrease > 30% of baseline value) and bradycardia (heart rate < 60 bpm) p-value < 0.05 was considered significant. RESULTS: Incidence of hypotension and bradycardia were 52.6% and 2.5%. The probability of hypotension increased with estimated blood loss 500-1000 mL (odds ratio [OR] = 1.86; 95% CI 1.30-2.67, p = 0.001), estimated blood loss > 1000 mL (OR = 5.31; 95% CI 1.47-19.19, p = 0.011), and analgesia level > T4 (OR = 1.94; 95% CI 1.18-3.19, p = 0.009). Hypotension occurred despite left uterine displacement (OR = 1.56; 95% CI 1.11-2.19, p = 0.01). Risk factors associated with bradycardia were adding intrathecal morphine 0.2 mg (0.2 mL) (OR = 4.61; 95% CI 1.31-16.19, p = 0.017) to local anesthetics. CONCLUSION: The present results indicated that the incidence of hypotension after spinal anesthesia for cesarean section increased with amount of estimated blood loss > 500 mL and analgesic level > T4. Adding intrathecal morphine 0.2 mg (0.2 mL) to local anesthetics increased incidence of bradycardia.

Sedation in patients above 60 years of age undergoing urological surgery under spinal anesthesia: comparison of propofol and midazolam infusions.

CONTEXT: Propofol and midazolam are commonly used sedatives during regional anesthesia in adults. Smaller doses of these drugs are required in older age due to altered pharmacokinetics and pharmacodynamics. AIMS: To study the sedation, side-effects and the costs involved with smaller doses of propofol and midazolam in patients aged above 60 years during spinal anesthesia. SETTINGS AND DESIGN: A randomized single-blind study was conducted in 60 ASA I-II patients aged > or = 60 years undergoing urological surgery under spinal anesthesia. MATERIALS AND METHODS: Sedation was administered after spinal anesthesia using propofol (bolus 0.4 mg.kg -1; infusion 3 mg/kg/hr) or midazolam (bolus 0.02 mg/kg; infusion 0.06 mg.kg -1.h -1) and titrated to achieve a sedation score of 3 on the modified Observer's Assessment of Alertness/Sedation Scale. Perioperative sedation, hemodynamics and respiratory events were monitored. STATISTICAL ANALYSIS: The analysis for parametric data was done using Student's unpaired t test and the incidence data using Chi-square test. RESULTS: The onset (13.0+/-4.2 vs. 18.8+/-4.2 min, P < 0.001) and offset (8.9+/-2.8 vs. 12.5+/-3.5 min, P < 0.001) of sedation were faster and the duration of adequate sedation longer (44.7+/-12.5 vs. 29.8+/-12.9% of total infusion time, P < 0.001) with propofol than midazolam. More patients receiving propofol compared to midazolam had hypotension (16 [50%] vs.4 [14.3%], P= 0.003). Airway obstruction occurred frequently in both the groups. Sedation was significantly more expensive with propofol than midazolam (US$ 9.83 +/- 2.80 vs. US$ 0.33 +/- 0.06, P 0.001). CONCLUSIONS: Propofol provided better titration and adequacy of sedation than midazolam in patients above 60 years of age, but caused hypotension. Lighter sedation is recommended in this age group.

Efeito do propofol associado à efedrina no tempo de latência do cisatracúrio / Effect of propofol in combination with ephedrine upon the onset time of cisatracurium

OBJETIVOS: Este estudo teve por objetivo avaliar a eficácia da efedrina na prevenção dos efeitos hemodinâmicos induzidos pela associação do propofol e do remifentanil, assim como os efeitos sobre o tempo de latência do cisatracúrio. MÉTODOS: Sessenta pacientes com idade entre 18 e 52 anos, estado físico ASA I ou II, foram divididos em três grupos, aleatoriamente: G I - propofol 1 por cento; G II - propofol 1 por cento + efedrina 0,5 mg.ml-1 e G III - propofol 1 por cento + efedrina 1,0 mg.ml-1 (velocidade de infusão igual a 180 ml.h-1), até a perda da consciência. Administrou-se remifentanil (0,5 mg.kg-1.min-1) e cisatracúrio na dose de 0,15 mg.kg-1. Foram registrados os dados demográficos, os sinais vitais (PAS, PAM, PAD, FC e SpO2) e o tempo de latência do cisatracúrio. RESULTADOS: Os grupos foram homogêneos com relação aos dados demográficos. Houve diminuição estatisticamente significativa dos valores de PAS, PAM, PAD e FC, um e três minutos após a administração do propofol, porém sem significado clínico importante e sem diferença entre os grupos. As medianas para os tempos de latência do cisatracúrio foram: 178 s (G2 e G3) e 183 s (G1), mas sem diferença significante entre os grupos. CONCLUSÃO: Não houve diminuição clinicamente importante dos parâmetros hemodinâmicos avaliados nos grupos que receberam ou não a efedrina e o tempo de latência do cisatracúrio foi o mesmo para os diferentes grupos.

OBJECTIVE: The onset time of neuromuscular blocking drugs is partially determined by circulatory factors, including muscle blood flow and cardiac output. The aim of the present paper was to: 1) compare the haemodynamic effects of adding different doses of ephedrine to an induction dose of propofol and remifentanil. 2) onset time of cisatracurium. METHODS: Sixty patients were randomly allocated into three groups: G1 - 1 percent propofol; G2 - 1 percent propofol + 0.5 mg.ml-1 ephedrine and G3 - 1 percent propofol + 1.0 mg.ml-1 ephedrine. All patients received continuous infusion of remifentanil (0.5 mg.kg-1.min-1). The rate of propofol infusion was 180 ml.h-1 until loss of consciousness and a loading dose of cisatracurium (0.15 mg.kg-1) was then given. After induction of anesthesia, the ulnar nerve was stimulated supramaximally every 10s, and the evoked twitch response of the adductor pollicis was recorded by accelerometry. RESULTS: There was no statistical difference between groups with respect to age, weight, dose of propofol administered and onset time of cisatracurium (tables 1, 2). Heart rate, SpO2, systolic, diastolic and mean blood pressures were compared at 1 and 3 min post-induction. There were statistical differences in HR, SAP, DAP and MAP, without significant adverse clinical effects. CONCLUSIONS: There were no clinically important decreases in the hemodynamic parameters evaluated in the groups receiving ephedrine or not, and the onset time of cisatracurium was the same for all groups.

Prospective study of hypotension and bradycardia during spinal anesthesia with bupivacaine: incidence and risk factors, part two.

OBJECTIVE: Hypotension and bradycardia during spinal anesthesia are common and may relate to severe adverse events such as cardiac arrest or death. The authors'first retrospective study identified three non-modfiiable factors including females, age more than 40 years, and type of operation. Level of blockage higher than T5 was the only one modifiable factor that could be confirmed That study was strongly limited by the nature of the retrospective anesthetic record reviewed study. MATERIAL AND METHOD: The authors prospectively studied the records of 2, 000 patients who received spinal anesthesia at Sriraj Hospital from 1 July 2004 to 31 December 2004. The collected parameters were patient demographic data (sex, age, body weight, height, ASA status), operative data (type of operation, emergency status, position and duration of operation), anesthetic data (type and dosage of local anesthetic agents used, intravenous fluid, vasoactive and sedative agents, highest sensory level of spinal blockage, usage and doses of spinal opioids). Recording forms of hypotension and bradycardia were completed by the responsible anesthetic team in each consecutive patient. RESULTS: Incidence of hypotension (20% or more decrease in systolic blood pressure) in the present study was 57.9%. The highest incidence was in cesarean section. Four non-modifiable risk factors could be identified which included females, age more than 50, body mass index more than 35 (OR = 2.1, 95% CI 1.01-4.29) and type of operation. Two modifiable risk factors included high dose of heavy bupivacaine (OR 1. 88, 95%CI 1. 3-2.74) and level of sensory blockage equal to or higher than T5 (OR 2.27, 95%CI 1.73-2.97). CONCLUSION: Usage of high dose of heavy bupivacaine and level of blockage higher than T5 were two modifiable risk factors associated with hypotension during spinal anesthesia. Avoidance of high block and lower dose of heavy bupivacaine can reduced the incidence and severity of hypotension after spinal anesthesia.

Inhaled iloprost for severe persistent pulmonary hypertension of the newborn.

The authors report one case of persistent pulmonary hypertension that had hypoxia although receiving treatment with high frequency oscillation, inotropic drugs, blood transfusion, and oral sildenafil for pulmonary vasodilatation. The patient developed hypotension after two doses of oral sildenafil and no response to high dose of inotropic drugs. So aerosolized iloprost was given via endotracheal tube and oxygen saturation improved within 10 minutes. Oxygen was weaned at 36 hours after treatment with this drug and no any side effect was found.