[Patient satisfaction with spinal cord stimulation for failed back surgery syndrome]. / Satisfacción del paciente con síndrome de dolor de raquis postquirúrgico portador de un sistema de neuroestimulación medular.

INTRODUCTION: The incidence of failed back surgery syndrome is about 40%. We studied the efficacy of and patient satisfaction with use of a spinal cord stimulator to treat this syndrome. MATERIAL AND METHODS: A period of 72 months of experience with implanted spinal cord stimulators was analyzed in this observational, descriptive study of patients who were included retrospectively. Patients met criteria for failed back surgery syndrome according to the taxonomy of the International Association for the Study of Pain. A chi2 test was used to compare qualitative variables. Results for quantitative variables were compared by analysis of variance. Statistical significance was set at P < 0.05. RESULTS: Thirty-four patients were studied. Both lumbar back and radicular pain assessed on a visual analog scale (VAS) decreased significantly from the mean overall score of 6. As time passed, fewer patients felt the system met their expectations. More patients said the system met their expectations in the first months after implantation (73.5%) than at a later interview (55.9%). Seventeen complications were reported, the most common being mechanical difficulties with the implanted stimulator. None of the complications were serious. Use of additional medication to control pain decreased in 38.2% of the cases. A total of 73.5% of the patients considered the implanted stimulator to be beneficial and 67.6% would have a spinal cord stimulator implanted again. CONCLUSIONS: Spinal cord stimulation improves lumbar back pain in patients with failed back surgery syndrome and reduces the amount of additional medication taken to control pain. It is important for patients to adjust their expectations about the implanted stimulator.

Satisfacción del paciente con síndrome de dolor de raquis postquirúrgico portador de un sistema de neuroestimulación medular / Patient satisfaction with spinal cord stimulation for failed back surgery syndrome

INTRODUCCIÓN: El síndrome de dolor de raquis postquirúrgico (SDRPQ) presenta una incidencia de hasta un 40% tras cirugía lumbosacra. Estudiamos la eficacia y satisfacción de los pacientes portadores de un sistema de neuroestimulación de la médula espinal. MATERIAL Y MÉTODO: Estudio observacional, retrospectivo, descriptivo de 72 meses de duración en pacientes portadores de un neuroestimulador medular con criterios de taxonomía descritos por la IASP para SDRPQ. Estudio estadístico Chi cuadrado para variables cualitativas y ANOVA para las cuantitativas. Significativos valores de p < 0,05. RESULTADOS: Se incluyeron 34 pacientes. Encontramos una disminución significativa del dolor en la EVA tanto para la lumbalgia como para el dolor radicular (EVAglobal con una media de 6). Encontramos una disminución en el ajuste de las expectativas respecto al sistema al transcurrir el tiempo. Un porcentaje superior de pacientes expresan ajuste adecuado a sus expectativas, 73,5% en los primeros meses del implante y 55,9% al momento de la entrevista respectivamente. Se recogieron un total de 17 complicaciones, ninguna grave, siendo las más frecuentes las mecánicas relacionadas con el sistema implantado. La medicación coadyuvante para controlar el dolor disminuyó en un 38,2% de los casos. El 73,5% de los pacientes encontró beneficioso el sistema implantado y el 67,6% se implantaría nuevamente otro sistema de neuroestimulación medular. CONCLUSIONES: La neuroestimulación medular proporciona mejoría al dolor lumbar en pacientes con SDRPQ y disminuye la ingesta de medicación coadyuvante para controlar el dolor. Es importante ajustar las expectativas del paciente ante el sistema implantado

INTRODUCTION: The incidence of failed back surgery syndrome is about 40%. We studied the efficacy of and patient satisfaction with use of a spinal cord stimulator to treat this syndrome. MATERIAL AND METHODS: A period of 72 months of experience with implanted spinal cord stimulators was analyzed in this observational, descriptive study of patients who were included retrospectively. Patients met criteria for failed back surgery syndrome according to the taxonomy of the International Association for the Study of Pain. A X2 test was used to compare qualitative variables. Results for quantitative variables were compared by analysis of variance. Statistical significance was set at P<0.05. RESULTS: Thirty-four patients were studied. Both lumbar back and radicular pain assessed on a visual analog scale (VAS) decreased significantly from the mean overall score of 6. As time passed, fewer patients felt the system met their expectations. More patients said the system met their expectations in the first months after implantation (73.5%) than at a later interview (55.9%). Seventeen complications were reported, the most common being mechanical difficulties with the implanted stimulator. None of the complications were serious. Use of additional medication to control pain decreased in 38.2% of the cases. A total of 73.5% of the patients considered the implanted stimulator to be beneficial and 67.6% would have a spinal cord stimulator implanted again. CONCLUSIONS: Spinal cord stimulation improves lumbar back pain in patients with failed back surgery syndrome and reduces the amount of additional medication taken to control pain. It is important for patients to adjust their expectations about the implanted stimulator

[Ketamine for subarachnoid anesthesia during hypovolemia: preliminary study in pigs]. / Utilización de ketamina para anestesia subaracnoidea durante hipovolemia. Estudio experimental preliminar en cerdos.

OBJECTIVES: To assess whether subarachnoid ketamine has fewer hemodynamic effects than lidocaine in normal and hypovolemic pigs and to determine whether or not the effects of ketamine are dose-dependent. METHODS: Thirty pigs were randomly allocated to receive subarachnoid administration of lidocaine 2 mg x kg(-1), ketamine 1 mg x kg(-1) or ketamine 2 mg x kg(-1), in a situation of either normal or reduced blood volume. The pigs were assigned to six groups: group L2 (2% lidocaine 2 mg x kg(-1), normovolemia), group L2H (2% lidocaine 2 mg x kg(-1), hypovolemia), group K1 (ketamine 1 mg x kg(-1), normovolemia), group K1H (ketamine 1 mg x kg(-1), hypovolemia), group K2 (ketamine 2 mg.kg(-', normovolemia), and group K2H (ketamine 2 mg x kg(-1), hypovolemia). To induce hypovolemia 30% of the calculated blood volume was withdrawn from each pig. The subarachnoid space was catheterized, and invasive measurements of hemodynamic variables (derived from arterial, central venous and pulmonary artery catheter monitoring) were obtained. Variables were recorded at baseline and 5 and 15 min after drug injection in the normovolemic groups, and at baseline after inducing hypovolemia and 5 and 15 min after drug injection in the hypovolemic groups. RESULTS: In the normovolemic pigs no significant differences were detected between groups. In hypovolemic pigs differences were observed in heart rate and arterial pressure between the ketamine 1 mg x kg(-1) and lidocaine 2 mg x kg(-1) groups (P < 0.05). The decreases in heart rate and arterial pressure were less marked in the ketamine group. Mixed venous oxygen saturation and cardiac index deteriorated to a lesser degree in both ketamine groups than in the lidocaine groups (P < 0.05). CONCLUSIONS: Racemic ketamine administered by subarachnoid injection in hypovolemic pigs produces less deterioration in hemodynamic variables than does lidocaine. Hemodynamic changes caused by ketamine were not dose-dependent. These findings may be of interest, given the increased use of ketamine in neuroaxial anesthesia and analgesia and perhaps the possible use of neuroaxial ketamine in hypovolemic patients.

Utilización de ketamina para anestesia subaracnoidea durante hipovolemia. Estudio experimental preliminar en cerdos / Ketamine for subarachoid anesthesia during hypovolemia: preliminary study in pigs

OBJETIVOS: Evaluar experimentalmente si la ketamina produce menor deterioro hemodinámico que la lidocaína en cerdos en situación de normovolemia y de hipovolemia. Determinar si los efectos hemodinámicos producidos por la ketamina son dosis dependientes. MÉTODOS: Treinta cerdos fueron distribuidos aleatoriamente para comparar el efecto de la administración subaracnoidea de 2 mg•kg-1 de lidocaína, 1 mg•kg-1 de ketamina y 2 mg•kg-1 de ketamina en situación de normovolemia y de hipovolemia inducida. Los animales fueron divididos en 6 grupos: grupo L2 (lidocaína 2% 2 mg•kg-1, en normovolemia), grupo L2H (lídocaína 2% 2 mg•kg-1, en hipovolemia), grupo K1 (ketamina ] mg•kg-1, en normovolemia), grupo K1H (ketamina 1 mg•kg-1, en hipovolemia), grupo K2 (ketamina 2 mg•kg-1, en normovolemia), grupo K2H (ketamina 2 mg•kg-1, en hipovolemia). Para inducir la hipovolemia se extrajo el 30% de la volemia calculada para cada animal. Se cateterizó el espacio subaracnoideo y se obtuvieron valores de variables hemodinámicas a través de monitorización arterial, venosa central y de arteria pulmonar. Se realizaron determinaciones basales y tras 5 y 15 minutos de la inyección del fármaco en situación de normovolemia, y determinaciones basales, tras inducir hipovolemia, y tras 5 y 15minutos de la inyección del fármaco en el grupo de hipovolemia. RESULTADOS: En normovolemia no se detectaron diferencias significativas entre los grupos. Durante la hipovolemia hubo diferencias en la frecuencia cardíaca y presión arterial entre ketamina 1 mg•kg-1 y lidocaína 2 mg•kg-1 (p<0,05). La frecuencia cardíaca y la presión arterial descendieron menos con la ketamina. La saturación venosa mixta de oxígeno y el índice cardíaco se deterioraron en menor grado en ambos grupos de ketamina que en el grupo de lidocaína (p<0,05). CONCLUSIONES: La ketamina subaracnoidea puede producir menor deterioro hemodinámico que la lidocaína durante la hipovolemia inducida, en cerdos. Los cambios hemodinámicos causados por la ketamina no son dosis dependientes. Estos hallazgos podrían ser interesantes debido al incremento en el uso de la ketamina por vía neuroaxial, así como su posible utilización en pacientes en situación hipovolémica (AU)

OBJETIVES: To assess whether subarachnoid ketamine has fewer hemodynamic effects than lidocaine in normal and hypovolemic pigs and to determine whether or not the effects of ketamine are dose-dependent. METIHODS: Thirty pigs were randomly allocated to receive subarachnoid administration of lidocaine 2 mg•kg-1, ketamine 1 mg•kg-1 or ketamine 2 mg•kg-1, in a situation of either normal or reduced blood volume. The pigs were assigned to six groups: group L2 (2% lidocaine 2 mg•kg-1, normovolemia), group L2H (2% lidocaine 2 mg•kg-1, hypovolemia), group K1 (ketamine 1 mg•kg-1, normovolemia), group K1H (ketamine 1 mg•kg-1, hypovolemia), group K2 (ketamine 2 mg•kg-1, normovolemia), and group K2H (ketamine 2 mg•kg-1, hypovolemia). To induce hypovolemia 30% of the calculated blood volume was withdrawn from each pig. The subarachnoid space was catheterized, and invasive measurements of hemodynamic variables (derived from arterial, central venous and pulmonary artery catheter monitoring) were obtained. Variables were recorded at baseline and 5 and 15 min after drug injection in the normovolemic groups, and at baseline after inducing hypovolemia and 5 and 15 min after drug injection in the hypovolemic groups. RESULTS: In the normovolemic pigs no significant differences were detected between groups. In hypovolemic pigs differences were observed in heart rate and arterial pressure between the ketamine 1 mg•kg-1 and lidocaine 2 mg•kg-1 groups (P<0.05). The decreases in heart rate and arterial pressure were less marked in the ketamine group. Mixed venous oxygen saturation and cardiac index deteriorated to a lesser degree in both ketamine groups than in the lidocaine groups (P<0.05). CONCLUSIONS: Racemic ketamine administered by subarachnoid injection in hypovolemic pigs produces less deterioration in hemodynamic variables than does lidocaine. Hemodynamic changes caused by ketamine were not dose-dependent. These findings may be of interest, given the increased use of ketamine in neuroaxial anesthesia and analgesia and perhaps the possible use of neuroaxial ketamine in hypovolemic patients (AU)

[Epidural anesthesia and analgesia in the perioperative treatment of a patient with Kartagener syndrome]. / Anestesia y analgesia epidurales en el tratamiento perioperatorio de una paciente con síndrome de Kartagener.

Kartagener's syndrome is an inherited disease characterized by a triad of symptoms--bronchiectasis, situs inversus and sinusitis--and is classified as an immotile cilia syndrome. Patients may experience specific airway problems when undergoing anesthesia for surgical procedures. We report the case of a woman with Kartagener's syndrome who underwent surgery under epidural anesthesia with postoperative epidural analgesia, both techniques proving successful.