SARS-CoV-2 infection. Descriptive analysis of a selected case series.

OBJECTIVES: COVID-19 was declared pandemic by March 2020. Clinical, analytical, and radiological findings have been reported. Detailed different evolution of patients of the same local outbreak has been scarcely reported. We report 6 selected cases of such an evolution. CLINICAL CASES: The clinical, radiological, analytical evolution of 6 patients is reported. Patients were selected as it were epidemiological close contacts, and showed particular different clinical evolution. RESULTS: The clinical course at the start of infection (first week) was similar among patients. In relationship with clinical evolution, middle to severe course were related with inflammation markers levels evolution (D-dimer, IL-6, ferritin, lymphocytes count, etc.). Specially lung alterations were observed, but neurological/neuropsychiatric findings are still common. In evolution, 2 patients showed middle symptoms, but the 2 most severely affected died. CONCLUSIONS: It remains to be elucidated the different evolutive pathways and outcomes of COVD-19. In our 6 patients of the same local outbreak, clinical, laboratory and radiological features were different. We discuss some aspects of the pathophysiology of the disease, other than the widely described of the respiratory system.

Infección por SARS-CoV-2. Análisis descriptivo de una serie de casos seleccionada / SARS-CoV-2 infection. Descriptive analysis of a selected case series

Objetivos: La COVID-19 fue declarada pandemia en marzo del 2020. Han sido comunicados los hallazgos clínicos, analíticos y radiológicos. Sin embargo, la diversa evolución de pacientes del mismo brote local lo ha sido escasamente. Comunicamos en este trabajo 6 casos seleccionados de tal evolución. Casos clínicos: Se expone la evolución clínica, radiológica y analítica de 6 pacientes. Estos fueron seleccionados ya que fueron epidemiológicamente contactos estrechos y mostraron una evolución clínica particularmente diferente. Resultados: El curso clínico al inicio de la infección (primera semana) fue similar entre los pacientes. En relación con la evolución clínica, un curso moderado a severo se relacionó evolutivamente con marcadores elevados de inflamación (dímero D, IL-6, ferritina, linfopenia, etc.). Fueron observadas alteraciones pulmonares típicas, pero fueron comunes también hallazgos neurológicos y neuropsiquiátricos. En la evolución 2pacientes mostraron síntomas moderados, pero los 2 más gravemente afectados murieron. Conclusiones: Está por elucidar las diferentes vías evolutivas y resultados finales de los pacientes con COVID-19. En nuestros 6 pacientes del mismo brote local, las características clínicas, de laboratorio y radiológicas fueron diferentes. Discutimos aspectos de la fisiopatología de la enfermedad distintos de los ampliamente descritos del sistema respiratorio.(AU)

Objectives: COVID-19 was declared pandemic by March 2020. Clinical, analytical, and radiological findings have been reported. Detailed different evolution of patients of the same local outbreak has been scarcely reported. We report 6 selected cases of such an evolution. Clinical cases: The clinical, radiological, analytical evolution of 6patients is reported. Patients were selected as it were epidemiological close contacts, and showed particular different clinical evolution. Results: The clinical course at the start of infection (first week) was similar among patients. In relationship with clinical evolution, middle to severe course were related with inflammation markers levels evolution (D-dimer, IL-6, ferritin, lymphocytes count, etc.). Specially lung alterations were observed, but neurological/neuropsychiatric findings are still common. In evolution, 2patients showed middle symptoms, but the 2most severely affected died. Conclusions: It remains to be elucidated the different evolutive pathways and outcomes of COVD-19. In our 6 patients of the same local outbreak, clinical, laboratory and radiological features were different. We discuss some aspects of the pathophysiology of the disease, other than the widely described of the respiratory system.(AU)

[SARS-CoV-2 infection. Descriptive analysis of a selected case series]. / Infección por SARS-CoV-2. Análisis descriptivo de una serie de casos seleccionada.

OBJECTIVES: COVID-19 was declared pandemic by March 2020. Clinical, analytical, and radiological findings have been reported. Detailed different evolution of patients of the same local outbreak has been scarcely reported. We report 6 selected cases of such an evolution. CLINICAL CASES: The clinical, radiological, analytical evolution of 6 patients is reported. Patients were selected as it were epidemiological close contacts, and showed particular different clinical evolution. RESULTS: The clinical course at the start of infection (first week) was similar among patients. In relationship with clinical evolution, middle to severe course were related with inflammation markers levels evolution (D-dimer, IL-6, ferritin, lymphocytes count, etc.). Specially lung alterations were observed, but neurological/neuropsychiatric findings are still common. In evolution, 2 patients showed middle symptoms, but the 2 most severely affected died. CONCLUSIONS: It remains to be elucidated the different evolutive pathways and outcomes of COVD-19. In our 6 patients of the same local outbreak, clinical, laboratory and radiological features were different. We discuss some aspects of the pathophysiology of the disease, other than the widely described of the respiratory system.

SARS-CoV-2 infection. Descriptive analysis of a selected case series. / Infección por SARS-CoV-2. Análisis descriptivo de una serie de casos seleccionada.

OBJECTIVES: COVID-19 was declared pandemic by March 2020. Clinical, analytical, and radiological findings have been reported. Detailed different evolution of patients of the same local outbreak has been scarcely reported. We report 6 selected cases of such an evolution. CLINICAL CASES: The clinical, radiological, analytical evolution of 6patients is reported. Patients were selected as it were epidemiological close contacts, and showed particular different clinical evolution. RESULTS: The clinical course at the start of infection (first week) was similar among patients. In relationship with clinical evolution, middle to severe course were related with inflammation markers levels evolution (D-dimer, IL-6, ferritin, lymphocytes count, etc.). Specially lung alterations were observed, but neurological/neuropsychiatric findings are still common. In evolution, 2patients showed middle symptoms, but the 2most severely affected died. CONCLUSIONS: It remains to be elucidated the different evolutive pathways and outcomes of COVD-19. In our 6patients of the same local outbreak, clinical, laboratory and radiological features were different. We discuss some aspects of the pathophysiology of the disease, other than the widely described of the respiratory system.

Effect of an individualized versus standard pneumoperitoneum pressure strategy on postoperative recovery: a randomized clinical trial in laparoscopic colorectal surgery.

BACKGROUND: It remains uncertain whether individualization of pneumoperitoneum pressures during laparoscopic surgery improves postoperative recovery. This study compared an individualized pneumoperitoneum pressure (IPP) strategy with a standard pneumoperitoneum pressure (SPP) strategy with respect to postoperative recovery after laparoscopic colorectal surgery. METHODS: This was a multicentre RCT. The IPP strategy comprised modified patient positioning, deep neuromuscular blockade, and abdominal wall prestretching targeting the lowest intra-abdominal pressure (IAP) that maintained acceptable workspace. The SPP strategy comprised patient positioning according to the surgeon's preference, moderate neuromuscular blockade and a fixed IAP of 12 mmHg. The primary endpoint was physiological postoperative recovery, assessed by means of the Postoperative Quality of Recovery Scale. Secondary endpoints included recovery in other domains and overall recovery, the occurrence of intraoperative and postoperative complications, duration of hospital stay, and plasma markers of inflammation up to postoperative day 3. RESULTS: Of 166 patients, 85 received an IPP strategy and 81 an SPP strategy. The IPP strategy was associated with a higher probability of physiological recovery (odds ratio (OR) 2·77, 95 per cent c.i. 1·19 to 6·40, P = 0·017; risk ratio (RR) 1·82, 1·79 to 1·87, P = 0·049). The IPP strategy was also associated with a higher probability of emotional (P = 0·013) and overall (P = 0·011) recovery. Intraoperative adverse events were less frequent with the IPP strategy (P < 0·001) and the plasma neutrophil-lymphocyte ratio was lower (P = 0·029). Other endpoints were not affected. CONCLUSION: In this cohort of patients undergoing laparoscopic colorectal surgery, an IPP strategy was associated with faster recovery, fewer intraoperative complications and less inflammation than an SPP strategy. Registration number: NCT02773173 ( http://www.clinicaltrials.gov).

ANTECEDENTES: No se sabe con certeza si individualizar las presiones del neumoperitoneo durante la cirugía laparoscópica mejora la recuperación postoperatoria. Comparamos una estrategia con individualización de la presión del neumoperitoneo (individualised pneumoperitoneum pressure, IPP) frente a una estrategia con presión estándar del neumoperitoneo (standard pneumoperitoneum pressure, SPP) respecto a la recuperación postoperatoria tras cirugía colorrectal laparoscópica. MÉTODOS: Ensayo clínico aleatorizado multicéntrico. La estrategia IPP consistió en una modificación de la posición, bloqueo neuromuscular profundo, y una distensión de la pared abdominal conseguida con la presión intraabdominal (intra-abdominal pressure, IAP) más baja en la que el espacio quirúrgico operativo siguiera siendo aceptable. La estrategia SPP consistió en una posición de acuerdo con la preferencia del cirujano, bloqueo neuromuscular moderado, e IAP fija de 12 mm Hg. El resultado primario fue la recuperación fisiológica postoperatoria, evaluada mediante la escala de calidad en la recuperación postoperatoria (Postoperative Quality of Recovery Scale, PQRS). Los resultados secundarios incluyeron la recuperación en otros dominios y la recuperación global, la aparición de complicaciones intraoperatorias y postoperatorias, duración de la estancia hospitalaria, y los valores de los marcadores inflamatorios séricos durante tres días postoperatorios. RESULTADOS: De un total de 166 pacientes, 85 recibieron una estrategia IPP y 81 una estrategia SPP. La estrategia IPP se asoció con una elevada probabilidad de recuperación fisiológica (razón de oportunidades, odds ratio OR, 2,8 (i.c. del 95% 1,2-6,4); P = 0,017, razón de riesgo, 1,8 (i.c. del 95% 1,7-1,9), P = 0,05)). La estrategia IPP también se asoció con una elevada probabilidad de recuperación emotiva (P = 0,013) y global (P = 0,011). Los eventos adversos intraoperatorios fueron menos frecuentes con la estrategia IPP (P < 0,001) y la tasa neutrófilo-linfocito fue más baja (P = 0,029). No se observaron cambios en otras variables. CONCLUSIÓN: En esta cohorte de pacientes sometidos a cirugía colorrectal laparoscópica, una estrategia IPP se asoció con una recuperación más rápida, menos complicaciones intraoperatorias y menos inflamación en comparación con una estrategia SPP.

Correction to: An individualised versus a conventional pneumoperitoneum pressure strategy during colorectal laparoscopic surgery: rationale and study protocol for a multicentre randomised clinical study.

After publication of our article [1] the authors have notified us that there are changes in the primary outcome and the statistical analysis plan of the study.

An individualised versus a conventional pneumoperitoneum pressure strategy during colorectal laparoscopic surgery: rationale and study protocol for a multicentre randomised clinical study.

BACKGROUND: A recent study shows that a multifaceted strategy using an individualised intra-abdominal pressure titration strategy during colorectal laparoscopic surgery results in an acceptable workspace at low intra-abdominal pressure in most patients. The multifaceted strategy, focused on lower to individualised intra-abdominal pressures, includes prestretching the abdominal wall during initial insufflation, deep neuromuscular blockade, low tidal volume ventilation settings and a modified lithotomy position. The study presented here tests the hypothesis that this strategy improves outcomes of patients scheduled for colorectal laparoscopic surgery. METHODS: The Individualized Pneumoperitoneum Pressure in Colorectal Laparoscopic Surgery versus Standard Therapy (IPPCollapse-II) study is a multicentre, two-arm, parallel-group, single-blinded randomised 1:1 clinical study that runs in four academic hospitals in Spain. Patients scheduled for colorectal laparoscopic surgery with American Society of Anesthesiologists classification I to III who are aged > 18 years and are without cognitive deficits are randomised to an individualised pneumoperitoneum pressure strategy (the intervention group) or to a conventional pneumoperitoneum pressure strategy (the control group). The primary outcome is recovery assessed with the Post-operative Quality of Recovery Scale (PQRS) at postoperative day 1. Secondary outcomes include PQRS score in the post anaesthesia care unit and at postoperative day 3, postoperative complications until postoperative day 28, hospital length of stay and process-related outcomes. DISCUSSION: The IPPCollapse-II study will be the first randomised clinical study that assesses the impact of an individualised pneumoperitoneum pressure strategy focused on working with the lowest intra-abdominal pressure during colorectal laparoscopic surgery on relevant patient-centred outcomes. The results of this large study, to be disseminated through conference presentations and publications in international peer-reviewed journals, are of ultimate importance for optimising the care and safety of laparoscopic abdominal surgery. Selection of patient-reported outcomes as the primary outcome of this study facilitates the translation into clinical practice. Access to source data will be made available through anonymised datasets upon request and after agreement of the Steering Committee of the IPPCollapse-II study. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02773173 . Registered on 16 May 2016. EudraCT, 2016-001693-15. Registered on 8 August 2016.

The fragility of statistically significant findings in randomised controlled anaesthesiology trials: systematic review of the medical literature.

The fragility index (FI), the number of events the statistical significance a result depends on, and the number of patients lost to follow-up are important parameters for interpreting randomised clinical trial results. We evaluated these two parameters in randomised controlled trials in anaesthesiology. For this, we performed a systematic search of the medical literature, seeking articles reporting on anaesthesiology trials with a statistically significant difference in the primary outcome and published in the top five general medicine journals, or the top 15 anaesthesiology journals. We restricted the analysis to trials reporting clinically important primary outcome measures. The search identified 139 articles, 35 published in general medicine journals and 104 in anaesthesiology journals. The median (inter-quartile range) sample size was 150 (70-300) patients. The FI was 4 (2-17) and 3 (2-7), and the number of patients lost to follow-up was 0 (0-18) and 0 (0-6) patients in trials published in general medicine and anaesthesiology journals, respectively. The number of patients lost to follow-up exceeded the FI in 41 and 27% in trials in general medicine journals and anaesthesiology journals, respectively. The FI positively correlated with sample size and number of primary outcome events, and negatively correlated with the reported P-values. The results of this systematic review suggest that statistically significant differences in randomised controlled anaesthesiology trials are regularly fragile, implying that the primary outcome status of patients lost to follow-up could possibly have changed the reported effect.

Repeated sugammadex reversal of muscle relaxation during lumbar spine surgery with intraoperative neurophysiological multimodal monitoring.

Intraoperative neurophysiological monitoring during spine surgery is usually acomplished avoiding muscle relaxants. A case of intraoperative sugammadex partial reversal of the neuromuscular blockade allowing adequate monitoring during spine surgery is presented. A 38 year-old man was scheduled for discectomy and vertebral arthrodesis throughout anterior and posterior approaches. Anesthesia consisted of total intravenous anesthesia plus rocuronium. Intraoperatively monitoring was needed, and the muscle relaxant reverted twice with low dose sugammadex in order to obtain adequate responses. The doses of sugammadex used were conservatively selected (0.1mg/kg boluses increases, total dose needed 0.4mg/kg). Both motor evoqued potentials, and electromyographic responses were deemed adequate by the neurophysiologist. If muscle relaxation was needed in the context described, this approach could be useful to prevent neurological sequelae. This is the first study using very low dose sugammadex to reverse rocuronium intraoperatively and to re-establish the neuromuscular blockade.

Anestesia epidural: dosis test intravascular simulada con S(+)-ketamina, lidocaína y adrenalina. Estudio prospectivo, aleatorizado, doble ciego, controlado con placebo / Epidural anaesthesia: simulated intravascular test dose with S(+) ketamine, lidocaine and adrenaline. A prospective, randomized, double blind and placebo controlled study

Objetivo. La dosis test en anestesia epidural es una recomendación de seguridad. La especificidad y sensibilidad de los fármacos empleados no ha resultado concluyente. Nuestro objetivo fue comparar la efectividad de adrenalina, lidocaína y S(+)-ketamina como dosis test intravascular simulada, así como sus efectos adversos. Material y métodos. Estudio prospectivo, aleatorizado, doble ciego, controlado con placebo. Pacientes ASA I, sometidos a cirugía electiva. Los grupos de estudio fueron (asignación aleatoria): S(+)-ketamina 0,5 mg/kg-1 (grupo S + K), lidocaína 5% 1,5 mg/kg-1 (grupo L5%), adrenalina 15 μg (grupo ADR) y suero fisiológico 3 ml (grupo SF; grupo control). Se evaluaron los primeros 15 min tras la administración del fármaco. Se evaluó: FC, PAS, PAM, PAD y SpO2 a los 0 min (basal) y a los 2, 5, 8, 10 y 15 min de la inyección del fármaco de estudio. Se consideró positivo un incremento de al menos 20 lat/min respecto de la determinación basal, o un incremento de la PAS > 15 mm Hg. Se registraron efectos clínicos: aparición de sedación-hipnosis, mareo, nistagmo, percepción de sabor metálico, parestesias faciales o peribucales, tinnitus, así como cualquier otro efecto referido por los pacientes. Se calculó la sensibilidad y especificidad y la diferencia porcentual de la variación para comprobar su significación clínica. Resultados. Fueron incluidos 80 pacientes, 20 por grupo. Se encontraron diferencias significativas en la PAS, PAM y PAD que se incrementaron a los 2, 5, 8 y 10 min entre el grupo S(+)K y los otros 3 grupos (p < 0,05), así como en la FC a los 2, 5, 8, 10 y 15 min entre el grupo S(+)K y el resto (p < 0,05). La sensibilidad y especificidad fueron altas y significativas en el grupo S(+)K comparada con placebo desde el minuto 2 al 8, así como la diferencia porcentual en ese mismo intervalo. Hubo diferencias significativas en la incidencia de sedación-sueño, nistagmo y mareo, que fue mayor en el grupo S(+)K, pero no las hubo en la incidencia de sabor metálico, parestesias peribucales o tinnitus. Los efectos detectados en el grupo S(+)K aparecieron siempre antes de los 5 min de inyectado el fármaco. Conclusión. Tanto lidocaína como adrenalina a las dosis empleadas presentaron escasa sensibilidad y especificidad como dosis test epidural intravascular simulada. S(+)-ketamina es un posible marcador de una inyección accidental intravascular (AU)

Objective. The use of a test dose in epidural anaesthesia is a safety recommendation. However specificity and sensitivity of the drugs used with this indication have been not conclusive. The main objective of this study was to compare the effectiveness and the adverse effects of a simulated intravascular test dose of adrenaline, lidocaine and S(+)-ketamine. Material and methods. A prospective, randomized, double blinded, placebo controlled study was designed. ASA I patients scheduled for elective surgery were included. These were randomized to the following study groups: S(+)-ketamine 0.5 mg.kg-1 (S+K group), 5% lidocaine 1.5 mg.kg-1 (L5% group), adrenaline 15μg (ADR group), and physiological saline 3 ml (SF group; control group). An evaluation was made during the first 15 minutes after the study drug was administered. Variables including heart rate (HR) systolic and diastolic blood pressure (sBP and dBP), mean arterial pressure (MAP), and SpO2 were recorded at 0 min (baseline) and at 2, 5, 8, 10 and 15 minutes after drug injection. An increase of at least 20 beats per minute (bpm) in relation to the baseline measurement was considered a positive result, as was an increase sBP >15 mmHg. The clinical effects described as related to iv injection of the study drugs recorded were: sedation-hypnosis, dizziness, nystagmus, metallic taste perception, perioral or facial paresthesias, tinnitus, as well as any other effect the patients mentioned. Sensitivity and specificity were calculated as was the percent increase in the parameters in order to see if these were clinically useful. Results. A total of 80 patients, 20 per group, were included. The sBP, dBP, and MAP were significantly raised at the 2, 5, 8 and 10 minutes measurements in the S(+)K group compared to the rest of the groups (P<.05), as well as HR in the 2, 5, 8, 10 and 15 minute measurements in the S(+)K compared to the rest of the groups (P<.05). Sensitivity and specificity were high, and significant in the S(+)K group from minute 2 to minute 8 compared with the placebo group, as well as percentage points differences in the same interval. There were significant differences in the incidence of sedation-hypnosis, nystagmus and dizziness, which were more frequent in the S(+)K group. There were no differences in the incidence of metallic taste, perioral and facial paresthesias or tinnitus. The effects in the S(+)K group always occurred before minute 5 after drug injection. Conclusion. Both lidocaine an adrenaline at the scheduled doses showed low sensitivity and specificity as a simulated iv epidural test dose. S(+)-ketamine could be a feasible marker after accidental iv injection during epidural anaesthesia or analgesia (AU)

Valoración del daño miocárdico mediante la medición de la heart-fatty acid-binding protein en cirugía de revascularización coronaria sin circulación extracorpórea. Estudio preliminar / Evaluation of postoperative myocardial injury by heart-type fatty acid-binding protein in off-pump coronary artery bypass grafting surgery

Introducción y objetivos del estudio. El infarto de miocardio posoperatorio es una complicación grave y frecuente de la cirugía cardiaca. El diagnóstico en este contexto es, en ocasiones, difícil. El objetivo de este estudio es evaluar la cinética y la precisión diagnóstica de un nuevo marcador, la heart-type fatty acid-binding protein (h-FABP), en la detección precoz de daño miocárdico en pacientes sometidos a cirugía de revascularización coronaria sin circulación extracorpórea en comparación con los biomarcadores clásicos. Materiales y métodos. Se estudiaron prospectivamente 17 pacientes consecutivos sometidos a cirugía cardiaca de revascularización sin circulación extracorpórea. Se analizaron biomarcadores de lesión de isquemia miocárdica (h-FABP, troponina, creatincinasa [CK] y CK-MB) al inicio de la cirugía (T1), inmediatamente después de la revascularización (T2), al ingreso en la UCC (T3) y después de 4 (T4), 8 (T5), 24 (T6) y 48 h (T7). Se registraron las complicaciones isquémicas perioperatorias, definidas de acuerdo con criterios electrocardiográficos, ecocardiográficos y hemodinámicos. Resultados. Los valores plasmáticos pico de la troponina se alcanzaron en T4 (2,9 ± 5,2 ng/ml) y en T5 con h-FABP (37,9 ± 55,5 ng/ml). Los valores máximos de CK y CK-MB fueron más tardíos, en T6 (741 ± 779 y 37 ± 51 U/L, respectivamente). El punto de corte obtenido para h-FABP para la detección de eventos isquémicos fue de 19 ng/ml, proporcionando una sensibilidad y especificidad del 77 y 75%, respectivamente, para el diagnóstico de la lesión isquémica perioperatoria, con un área bajo la curva ROC para h-FABP de 0,83 (IC 95% 0,6-1,0) vs. 0,63 (IC 95% 0,33-0,83) para troponina. Se alcanza este valor de corte para la h-FABP en promedio en T2 (18,9 ± 21,5 ng/ml). Conclusión. Este es el primer estudio que evalúa la cinética del biomarcador h-FABP en el perioperatorio de la cirugía de revascularización sin circulación extracorpórea, y el valor de corte establecido podría ayudar a la detección temprana de la isquemia miocárdica en este contexto (AU)

Background and goal of study. Postoperative myocardial infarction is a serious and frequent complication of cardiac surgery. Nonetheless, diagnosis in this context it is occasionally challenging. We sought to evaluate the kinetics and diagnostic accuracy of the new biomarker «heart-type fatty acid-binding protein» (h-FABP) in the early detection of myocardial injury in patients undergoing off-pump coronary artery bypass grafting, compared with classical biomarkers. Materials and methods. A prospective study was conducted on 17 consecutive patients who underwent off-pump coronary artery bypass grafting during a 2 month period. Blood samples were drawn for measurement of myocardial ischemic injury biomarkers (h-FABP, troponin, creatine kinase [CK] and CK-MB), at baseline (T1), immediate post-coronary artery bypass grafting (T2), on ICU admission (T3), and after 4 (T4), 8 (T5), 24 (T6) and 48 h (T7). Perioperative ischemic complications, defined according to electrocardiographic, echocardiographic and hemodynamic criteria, were recorded. Results. Earlier biomarkers peak plasma values occurred at T4 with troponin (2.9 ± 5.2 ng/mL), and at T5 with h-FABP (37.9 ± 55.5 ng/mL). Maximum values of CK and CK-MB occurred later, both in T6 (741 ± 779 and 37 ± 51 U/L, respectively). The optimized cut-off obtained for h-FABP was 19 ng/mL, providing a sensitivity and specificity of 77 and 75%, respectively, for diagnosis of perioperative ischemic injury, with an area under the ROC curve for h-FABP of 0.83 (95% CI 0.6-1.0) vs. 0.63 (95% CI 0.33-0.83) for troponin. This cut-off value for h-FABP is reached on average at T2 (mean value of h-FABP at T2: 18.9 ± 21.5 ng/mL). Conclusion. This is the first study evaluating the kinetics of h-FABP biomarker in perioperative off-pump coronary artery bypass grafting, and the cut-off value established could help to extend earlier detection of myocardial ischemia in this context (AU)

[Epidural anaesthesia: Simulated intravascular test dose with S(+) ketamine, lidocaine and adrenaline. A prospective, randomized, double blind and placebo controlled study]. / Anestesia epidural: dosis test intravascular simulada con S(+)-ketamina, lidocaína y adrenalina. Estudio prospectivo, aleatorizado, doble ciego, controlado con placebo.

OBJECTIVE: The use of a test dose in epidural anaesthesia is a safety recommendation. However specificity and sensitivity of the drugs used with this indication have been not conclusive. The main objective of this study was to compare the effectiveness and the adverse effects of a simulated intravascular test dose of adrenaline, lidocaine and S(+)-ketamine. MATERIAL AND METHODS: A prospective, randomized, double blinded, placebo controlled study was designed. ASA I patients scheduled for elective surgery were included. These were randomized to the following study groups: S(+)-ketamine 0.5 mg.kg-1 (S+K group), 5% lidocaine 1.5 mg.kg-1 (L5% group), adrenaline 15µg (ADR group), and physiological saline 3 ml (SF group; control group). An evaluation was made during the first 15 minutes after the study drug was administered. Variables including heart rate (HR) systolic and diastolic blood pressure (sBP and dBP), mean arterial pressure (MAP), and SpO2 were recorded at 0 min (baseline) and at 2, 5, 8, 10 and 15 minutes after drug injection. An increase of at least 20 beats per minute (bpm) in relation to the baseline measurement was considered a positive result, as was an increase sBP >15 mmHg. The clinical effects described as related to iv injection of the study drugs recorded were: sedation-hypnosis, dizziness, nystagmus, metallic taste perception, perioral or facial paresthesias, tinnitus, as well as any other effect the patients mentioned. Sensitivity and specificity were calculated as was the percent increase in the parameters in order to see if these were clinically useful. RESULTS: A total of 80 patients, 20 per group, were included. The sBP, dBP, and MAP were significantly raised at the 2, 5, 8 and 10 minutes measurements in the S(+)K group compared to the rest of the groups (P<.05), as well as HR in the 2, 5, 8, 10 and 15 minute measurements in the S(+)K compared to the rest of the groups (P<.05). Sensitivity and specificity were high, and significant in the S(+)K group from minute 2 to minute 8 compared with the placebo group, as well as percentage points differences in the same interval. There were significant differences in the incidence of sedation-hypnosis, nystagmus and dizziness, which were more frequent in the S(+)K group. There were no differences in the incidence of metallic taste, perioral and facial paresthesias or tinnitus. The effects in the S(+)K group always occurred before minute 5 after drug injection. CONCLUSION: Both lidocaine an adrenaline at the scheduled doses showed low sensitivity and specificity as a simulated iv epidural test dose. S(+)-ketamine could be a feasible marker after accidental iv injection during epidural anaesthesia or analgesia.