Rider sitting position widens lumbar intervertebral distance: a prospective observational study

Abstract Background: Reduced lumbar lordosis may make the process of identifying the intervertebral distance easier. The primary aim of this study was to measure the L3-L4 intervertebral space in the same patients undergoing spinal anesthesia in three different sitting positions, including the classic sitting position (CSP), hamstring stretch position (HSP) and rider sitting position (RSP). The secondary aim was to compare ultrasonographic measurements of the depth of the ligamentum flavum and intrathecal space in these three defined positions. Methods: This study is a single-blinded, prospective, randomized study. Ninety patients were included in final analysis. the patients were positioned on the operating table in three different positions to perform ultrasonographic measurements of the spinal canal. The intervertebral distance (IVD), the distance between the skin and the ligamentum flavum (DBSLF) and the intrathecal space (IS) were measured in the L3 -L4 intervertebral space in three different positions. Results: The RSP produced the largest mean distance between the spinous processes. The RSP yielded a significantly larger IVD than did the CSP (p < 0.001) and HSP (p < 0.001). The DBSP was larger in the CSP than in the HSP (p = 0.001). The DBSLF was significantly larger in the RSP than in the HSP (p = 0.009). Conclusions: Positioning the patient in the RSP significantly increased the intervertebral distance between L3 -L4 vertebrae compared to the CSP and HSP, suggesting easier performance of lumbar neuraxial block.

Effectiveness and safety of ultra-low-dose spinal anesthesia versus perineal blocks in hemorroidectomy and anal fistula surgery: a randomized controlled trial

Abstract Background: Ultra-low-dose Spinal Anesthesia (SA) is the practice of employing minimal doses of intrathecal agents so that only the roots that supply a specific area are anesthetized. The aim of this study was to compare the effectiveness and safety of ultra-low-dose spinal anesthesia with that of Perineal Blocks (PB). Methods: A two-arm, parallel, double-blind randomized controlled trial comparing two anesthetic techniques (SA and PB) for hemorrhoidectomy and anal fistula surgery was performed. The primary outcomes were postoperative pain, complementation and/or conversion of anesthesia, and hemodynamic changes. Results: Fifty-nine patients were included in the final analysis. The mean pain values were similar in the first 48 h in both groups (p > 0.05). The individuals allocated to the SA group did not need anesthetic complementation; however, those in the PB group required it considerably (SA group, 0% vs. PB group, 25%; p = 0.005). Hemodynamic changes were more pronounced after PB: during all surgical times, the PB group showed lower MAP values and higher HR values (p < 0.05). Postoperative urinary retention rates were similar between both groups (SA group 0% vs. PB group 3.1%, p = 0.354). Conclusion: SA and PB are similarly effective in pain control during the first 48 h after hemorrhoidec-tomy and anal fistula surgery. Although surgical time was shorter among patients in the PB group, the SA technique may be preferable as it avoids the need for additional anesthesia. Furthermore, the group that received perineal blocks was under sedation with a considerable dose of propofol.

Safety and effectiveness of adding fentanyl or sufentanil to spinal anesthesia: systematic review and meta-analysis of randomized controlled trials

Abstract Introduction Spinal infusions of either fentanyl or sufentanil have been reported in international reports, articles, and scientific events worldwide. This study aimed to determine whether intrathecal fentanyl or sufentanil offers safety in mortality and perioperative adverse events. Methods MEDLINE (via PubMed), EMBASE, CENTRAL (Cochrane library databases), gray literature, hand-searching, and clinicaltrials.gov were systematically searched. Randomized controlled trials with no language, data, or status restrictions were included, comparing the effectiveness and safety of adding spinal lipophilic opioid to local anesthetics (LAs). Data were pooled using the random-effects models or fixed-effect models based on heterogeneity. Results The initial search retrieved 4469 records; 3241 records were eligible, and 3152 articles were excluded after reading titles and abstracts, with a high agreement rate (98.6%). After reading the full texts, 76 articles remained. Spinal fentanyl and sufentanil significantly reduced postoperative pain and opioid consumption, increased analgesia and pruritus. Fentanyl, but not sufentanil, significantly reduced both postoperative nausea and vomiting, and postoperative shivering; compared to LAs alone. The analyzed studies did not report any case of in-hospital mortality related to spinal lipophilic opioids. The rate of respiratory depression was 0.7% and 0.8% when spinal fentanyl or sufentanil was added and when it was not, respectively. Episodes of respiratory depression were rare, uneventful, occurred intraoperatively, and were easily manageable. Conclusion There is moderate to high quality certainty that there is evidence regarding the safety and effectiveness of adding lipophilic opioids to LAs in spinal anesthesia.

Preoperative assessment of inferior vena cava collapsibility index by ultrasound is not a reliable predictor of post-spinal anesthesia hypotension

Abstract Background Post-spinal anesthesia hypotension is of common occurrence, and it hampers tissue perfusion. Several preoperative factors determine patient susceptibility to hypotension. This study aimed to assess the effectiveness of the Inferior Vena Cava Collapsibility Index (IVCCI) for predicting intraoperative hypotension. Methods One hundred twenty-nine adult patients who were scheduled for elective surgical procedures after administration of spinal (intrathecal) anesthesia were included in the study. Ultrasound evaluation of the Inferior Vena Cava (IVC) was done in the preoperative area, and the patients were shifted to the Operating Room (OR) for spinal anesthesia. An independent observer recorded the change in blood pressure after spinal anesthesia inside the OR. Results Twenty-five patients developed hypotension (19.37%). Baseline systolic blood pressure and mean blood pressures were statistically higher in those patients who developed hypotension (p= 0.001). The logistic regression analysis for IVCCI and the incidence of hypotension showed r2 of 0.025. Receiver Operating Characteristic (ROC) curve analysis demonstrated the Area Under the Curve (AUC) of 0.467 (95% Confidence Interval, 0.338 to 0.597; p= 0.615). Conclusions Preoperative evaluation of IVCCI is not a good predictor for the occurrence of hypotension after spinal anesthesia.

Rachianesthésie en ambulatoire au Centre Hospitalier Universitaire Andrainjato Fianarantsoa, Madagascar: tolérance et efficacité / Ambulatory spinal anaesthesia at the Andrainjato University Hospital of Fianarantsoa, Madagascar: tolerance and effectiveness

La rachianesthésie ambulatoire est une des méthodes d'anesthésies loco- régionales de plus en plus utilisées car permet une réhabilitation précoce. L'objectif de l'étude est d'évaluer la tolérance et l'efficacité de la rachianesthésie réalisée en ambulatoire. Méthodes : Il s'agit d'une étude rétrospective, analytique réalisée au Centre Hospitalier Universitaire Andrainjato Fianarantsoa pendant cinq ans (du mois de janvier 2016 au mois de décembre 2020). La tolérance de la rachianesthésie était évaluée par la fréquence et la gravité des incidents peropératoires et complications postopératoires. Son efficacité était estimée par le taux de sortie le jour de l'intervention et la ré-hospitalisation. Résultats : Soixante-quatre patients âgés de 44 [14-85] ans ont bénéficié d'une chirurgie viscérale, gynécologique, traumatologique ou vasculaire sous rachianesthésie. L'hypotension artérielle (n=04) et les nausées et vomissements peropératoires (n = 01) étaient les incidents retrouvés. Les complications postopératoires étaient la céphalée (n = 13), la douleur postopératoire d'intensité modérée à intense (n = 05) et les nausées et vomissements (n = 02). L'âge supérieur à 50 ans (p = 0,012) et une dose supérieure à 12 mg de bupivacaïne (p = 0,011) étaient corrélés à l'hypotension artérielle peropératoire. Le genre féminin (p = 0,004) et l'utilisation de la bupivacaïne hyperbare (p = 0,027) étaient associés aux complications postopératoires. Tous ces patients étaient sortis le jour même de l'intervention sans ré-hospitalisation. Conclusion : La rachianesthésie ambulatoire connaît actuellement un grand essor dans la pratique anesthésique. La prévention de certaines complications devrait être systématique afin d'optimiser sa tolérance et son efficacité

Facteurs de morbidité du syndrome de mal-être post-rachianesthésie / Morbidity factors of post-spinal anesthesia disease syndrome

La pratique de la rachianesthésie est motivée par la qualité de l'analgésie post-opératoire qu'elle procure. Cependant, la rachianesthésie reste comme tout acte médical associée à certains accidents. Méthodes : C'est une étude prospective, descriptive et analytique qui s'est déroulée sur une période d'un (01) mois allant du 07 Mai 2022 au 07 Juin 2022 au CHU d'Angré. Résultats : la rachianesthésie a été réalisée dans 188 des cas, soit un taux de 60% de l'ensemble des interventions. Le sexe ratio était de 0,13 et l'âge moyen était de 33 ± 10 ans. L'antécédent le plus retrouvé était l'HTA. La bupivacaine était le seul anesthésique local utilisé avec comme adjuvant la morphine, le fentanyl ou l'association morphine -fentanyl. Les incidents peropératoires étaient dominés par les troubles hémodynamiques à type d'hypotension artérielle (98,7%) et de bradycardie. Les patients ayant présenté un syndrome de mal être post opératoire représentaient 70,8% de notre effectif. Le Syndrome de Mal Etre post opératoires était dominé par les nausées et vomissements suivis des prurits. Tous les patients ayant présenté un syndrome de mal être post rachianesthésie n'avaient pas bénéficié de prise en charge. La survenue du syndrome de mal être post rachianesthésie était statistiquement associé à la présence de la morphine comme adjuvant (p=0,016). Conclusion : La rachianesthésie est une remarquable technique d'anesthésie. Néanmoins la fréquence des évènements per et post opératoires survenant au décours de cette technique n'est pas négligeable, car ils sont la source d'inconforts notables

Anestesia raquídea con bupivacaína isobárica en cesáreas / Spinal anesthesia with isobaric bupivacaine in cesarean sections

En la anestesia para las cesáreas, la anestesia raquídea con bupivacaína hiperbárica constituye la elección habitual en nuestro medio. Existen dos formas de bupivacaína disponibles, la isobárica (BI) y la hiperbárica (BH). La utilización de la BI es poco frecuente por lo que es relevante conocer la experiencia en su utilización para las anestesias de las cirugías obstétricas. El objetivo del estudio fue caracterizar la utilización de BI en las anestesias raquídeas para cesáreas. Se realizó un estudio observacional, descriptivo, de corte transversal en 23 pacientes que recibieron anestesia espinal con BI. La edad promedio fue de 28  5 años, la dosis promedio de BI utilizada de 9,4 mg. La latencia promedio fue 90 segundos y el tiempo para la instauración una anestesia adecuada fue en promedio 4,9 minutos. En el 82,6% el nivel anestésico alcanzó el dermatoma T4. En el 21,7% fue necesario administrar efedrina para aumentar la presión arterial. En el 52,1% se presentaron efectos adversos menores. A las 24 horas, el dolor fue nulo en 56,5% y leve en 43,5% de los casos. En conclusión, se encontró que las pacientes alcanzaron un nivel sensitivo adecuado en poco tiempo, con una dosis promedio de BI de 9 mg. Pocos pacientes requirieron la administración de un vasopresor para aumentar la presión arterial. Los efectos adversos fueron menores en casi la mitad de los pacientes. En el post operatorio la mayoría de las pacientes no presentaron dolor

In anesthesia for caesarean sections, spinal anesthesia with hyperbaric bupivacaine is the usual choice in our setting. There are two forms of bupivacaine available, isobaric (BI) and hyperbaric (BH). The use of BI is infrequent, so it is relevant to know the experience in its use for anesthesia in obstetric surgeries. The objective of the study was to characterize the use of BI in spinal anesthesia for cesarean sections. An observational, descriptive, cross-sectional study was carried out in 23 patients who received spinal anesthesia with BI. The average age was 28  5 years, the average dose of BI used was 9.4 mg. The average latency was 90 seconds and the time for establishment of adequate anesthesia was on average 4.9 minutes. In 82.6% of the cases, the anesthetic level reached dermatome T4. In 21.7% it was necessary to administer ephedrine to increase blood pressure. Minor adverse effects occurred in 52.1%. At 24 hours, the pain was null in 56.5% and mild in 43.5% of cases. In conclusion, it was found that the patients reached an adequate sensory level in a short time, with an average dose of BI of 9 mg. Few patients required administration of a vasopressor to increase blood pressure. Adverse effects were minor in almost half of the patients. In the postoperative period, most of the patients did not present pain

Sección de catéter epidural durante técnica anestésica espinal epidural combinada / Epidural catheter section during combined epidural spinal anesthetic technique

Estos son empleados con seguridad desde hace varias décadas; sin embargo, algunas complicaciones suelen presentarse. Una poco frecuente es su sección, la cual de no ser manejada adecuadamente genera importante morbilidad. Se presenta el caso de una paciente que recibe anestesia espinal epidural combinada. La técnica empleada, tanto para la colocación del catéter como para su retiro, aparentemente, fue correcta; sin embargo, este sufre una sección al retirarlo. En las imágenes posteriores se evidenciaría que el catéter se situó, accidentalmente, en el espacio paravertebral. Se teoriza un mecanismo de ruptura aun no descrito en la bibliografía. Se publica con el objetivo de mostrar la necesidad de la individualización en el manejo de este accidente, ya sea expectante o quirúrgico según las condiciones clínicas de cada paciente(AU)

The use of epidural catheters is a fundamental pillar of anesthesia. These have been safely employed for several decades; however, some complications usually occur. A rare one is its section, which if not properly managed generates significant morbidity. It is presented the case of a patient receiving combined epidural spinal anesthesia. The technique used, both for the placement of the catheter and for its removal, was apparently correct; however, it suffered a section when removed. In the subsequent images it was evident that the catheter was accidentally placed in the paravertebral space. A mechanism of rupture not yet described in the literature is theorized. It is published with the aim of showing the need for individualization in the management of this accident, whether expectant or surgical according to the clinical conditions of each patient(AU)

Prophylactic paracetamol for intraoperative shivering prevention for patients undergoing gynecological procedures under spinal anesthesia: A randomized clinical trial

Introduction@#Shivering is defined as an involuntary, repetitive activity of skeletal muscles. Mechanisms of shivering for patients undergoing surgical operation include intraoperative heat loss, increase sympathetic tone, pain, and systemic release of pyrogens. Regional anesthesia, particularly spinal anesthesia causes redistribution of core heat to the peripheral tissues this in turn predisposes patient to shivering and hypothermia. The median incidence of shivering related to regional anesthesia observed in a review of 21 studies is 55%. Paracetamol is one of the most commonly used analgesic and antipyretic drugs around the world, available without a prescription, it has analgesic and antipyretic property similar to NSAIDs it also affects core body temperature through the hypothalamus. Though different modalities have been established for shivering prevention, the search for a cost-effective drug with lesser side effects and improvement of patient satisfaction still continues. @*Objective@#The aim of this study was to evaluate the effect of prophylactic dose of Paracetamol on postanesthesia shivering on patients undergoing, gynecological procedures under spinal anesthesia as compared to patients not given Paracetamol.@*Methodology@#This is a Double blind, Randomized, Placebo Controlled conducted in patients scheduled for benign gynecological procedures such as Hysterectomy with or without adnexectomy. Using simple random sampling through fishbowl method and a sample size of 42, all patients who consented to participate in the study was randomly assigned to receive Paracetamol 900 mg IV or Placebo 0.9% Saline intravenously 30 minutes prior to induction of spinal anesthesia. Incidence and severity of Shivering was documented using shivering five point scale outlined by Crossley and Mahajan, while patient satisfaction was also evaluated using the Likert Scale, possible side effects was also assessed.

Juan Evangelista Manrique, the true pioneer of spinal anesthesia in Colombia / El verdadero pionero de la raquianestesia en Colombia: Juan Evangelista Manrique

Abstract Several findings paved the way to the use of the spinal approach for anesthesia. Information about the originators and dates of their discoveries is controversial. According to personal communications, doctors Juan Bautista Montoya y Flórez, in Medellín, and Lisandro Leyva, in Bogotá, in 1904 and 1905 respectively, would appear to be the pioneers of spinal anesthesia in Colombia. Pioneering cases of this procedure carried out in 1901 by doctor Juan Evangelista Manrique and which continued to be performed by his colleagues and assistants of the medical community at the time are documented in the Corporis Fabrica dissertation collection of the National University of Colombia.

Resumen Son varios los hallazgos que contribuyeron al abordaje de la columna vertebral como vía para la administración de anestesia. Los autores y las fechas de tales descubrimientos han sido controvertidos. En Colombia, según fuentes orales, los doctores Juan Bautista Montoya y Flórez, en Medellín, y Lisandro Leyva, en Bogotá, en 1904 y 1905 respectivamente, serían los pioneros de la anestesia raquídea en Colombia. En las tesis de la Facultad de Medicina de la Universidad Nacional, Colección Corporis Fabrica, se documentan los casos pioneros de este procedimiento realizados en 1901, por el doctor Juan Evangelista Manrique y continuados enseguida por sus colegas y ayudantes de la comunidad médica de ese entonces.

Seguridad de la anestesia neuroaxial en mujeres con embarazo gemelar y síndrome de transfusión feto-fetal, sometidas a fotocoagulación láser. Estudio de cohorte retrospectiva / Safety of neuraxial anesthesia in patients twin pregnancy and twin-to-twin transfusion syndrome taken to laser photocoagulation. Retrospective cohort study

Objetivo: describir las características clínicas y la frecuencia de complicaciones maternas, fetales y neonatales, según técnica de anestesia neuroaxial (AN) en mujeres con síndrome de transfusión feto-fetal (STFF) tratadas con fotocoagulación láser (FL). Materiales y métodos: estudio de cohorte retrospectiva descriptivo. Se incluyeron gestantes con STFF tratadas con FL y AN en la Fundación Valle del Lili, Cali (Colombia) entre 2013-2017. Se excluyeron pacientes con STFF estadio-V de Quintero. Se usó estadística descriptiva. El protocolo fue aprobado por el Comité de Ética de la institución. Resultados: 32 participantes cumplieron con los criterios de inclusión y de exclusión. La población estuvo constituida por mujeres jóvenes, multíparas. En el 87,5% de los casos se realizó intervención de urgencia. El 43,7% presentaba el estadio-III de Quintero y en el 56,2 % de las gestantes se utilizó anestesia epidural. Las variables hemodinámicas maternas exhibieron un comportamiento similar, acorde al momento de la cirugía y la técnica neuoraxial implementada. El 65,6 % de las gestantes presentó hipotensión sostenida y el 9,3 % desarrolló edema pulmonar. El 65,6 % de las pacientes experimentó parto pretérmino y el 18,7 % ruptura prematura de membranas. Se registraron 14 muertes fetales y cinco neonatales. No se registraron casos de mortalidad materna. Conclusiones: en pacientes con STFF que requieren FL, el uso de la anestesia epidural, espinal o combinada probablemente se asocia con un comportamiento similar al de las variables hemodinámicas maternas, durante los momentos de la cirugía. Los profesionales que brindan atención a estas gestantes deben estar alerta ante la frecuente aparición de complicaciones maternas, fetales y neonatales. Se requieren estudios prospectivos que evalúen la seguridad y la efectividad de las diferentes técnicas de anestesia neuroaxial en pacientes con STFF.

Objective: To describe the clinical characteristics and the frequency of maternal, fetal and neonatal complications in accordance with the neuraxial anesthesia (NA) technique in women with twin-to- twin transfusion syndrome (TTTS) treated with laser photocoagulation. Materials and Methods: Descriptive retrospective cohort study of pregnant patients with TTTS treated with laser photocoagulation under NA at Fundación Valle del Lili, Cali (Colombia), between 2013-2017. Patients with Quintero stage VTTTS were excluded. The protocol was approved by the institutional ethics committee. Results: Of the participants, 32 met the inclusion and exclusion criteria. The study population consisted of young, multiparous women. Urgent interventions were performed in 87.5% of cases; 43.7% were Quintero stage III and epidural anesthesia was used in 56.2% of the women. Maternal hemodynamic variables were similar, in accordance with the timing of surgery and the neuraxial technique used. Sustained hypotension occurred in 65.6% of the pregnant women and 9.3% developed pulmonary edema. Pre-term delivery occurred in 65.6% of the patients and 18.7% had premature rupture of membranes. There were 14 fetal demises and five neonatal deaths. There were no cases of maternal mortality. Conclusions: In patients with TTTS requiring laser photocoagulation, the use of epidural, spinal or combined anesthesia is likely associated with similar maternal hemodynamic variables at the time of surgery. Practitioners providing care to these pregnant women must be aware of the frequent occurrence of maternal, fetal and neonatal complications. Prospective studies to assess the safety and effectiveness of the different neuraxial anesthesia techniques in patients with TTTS are required.

Trombosis venosa profunda y trombofilia congénita / Deep-vein thrombosis and congenital thrombophilia

Introducción: La trombofilia es un desorden de la hemostasia congénito o adquirido que predispone al desarrollo de trombosis. Las trombofilias congénitas más frecuentes son las deficiencias de antitrombina III, proteína C y proteína S, el factor V Leiden, la mutación del gen de la protrombina (G20210A) y las mutaciones de la enzima metilentetrahidrofolato reductasa (MTHFR). Objetivo: Describir el manejo anestésico en un paciente portador de trombofilia congénita. Presentación del caso: Se reporta un paciente de 19 años de edad con antecedentes de historia familiar y personal de trombosis venosa profunda, tratamiento con doble antiagregación plaquetaria y asociación de tres mutaciones para trombofilia congénita, G20210A, A1298C MTHFR y C677T MTHFR que recibe anestesia espinal para una herniorrafia inguinal. Se mantiene tratamiento con aspirina, se suspende clopidogrel 7 días antes de la cirugía y durante ese tiempo se administra fraxiparina 0.6 Uds. subcutánea diarias hasta 12 h antes de la cirugía, se utiliza medias elásticas, deambulación precoz y reinicio de clopidogrel 24 h después de la cirugía, con evolución satisfactoria. Conclusiones: La tromboprofilaxis en pacientes portadores de trombofilia congénita es mandatoria, por eso resulta determinante la utilización de heparina de bajo peso molecular junto al resto de las medidas de prevención de la trombosis venosa profunda(AU)

Introduction: Thrombophilia is a congenital or acquired hemostasis disorder that predisposes to thrombosis development. The commonest congenital thrombophilias are deficiencies of antithrombin III, protein C and protein S, factor V Leiden, prothrombin gene mutation (G20210A), and methylenetetrahydrofolate reductase (MTHFR) mutations. Objective: To describe the anesthetic management in a patient with congenital thrombophilia. Case presentation: The case is reported of a 19-year-old patient with a family and personal history of deep-vein thrombosis, treatment with double antiplatelet therapy and association of three mutations for congenital thrombophilia (G20210A, A1298C MTHFR and C677T MTHFR), who receives spinal anesthesia for an inguinal herniorrhaphy. Aspirin treatment is maintained. Clopidogrel is suspended seven days before surgery. During this time, fraxiparin is administered subcutaneously in 0.6-mL units daily, up to twelve hours before surgery. Elastic stockings are used, early ambulation is allowed, and clopidogrel is restarted 24 hours after surgery, with satisfactory evolution. Conclusions: Thromboprophylaxis in patients with congenital thrombophilia is mandatory, a reason why the use of low-molecular-weight heparin, together with the rest of the prevention measures against deep-vein thrombosis, is decisive(AU)

Spinal anesthesia increases the frequency of extubation in the operating room and decreases the time of mechanical ventilation after cardiac surgery

Abstract Introduction: The delayed extubation of patients undergoing mechanical ventilation (MV) in the postoperative period of cardiac surgery (CS) is associated with mortality. The adoption of spinal anesthesia (SA) combined with general anesthesia in CS influences the orotracheal intubation time (OIT). This study aims to verify if the adoption of SA reduces the time of MV after CS, compared to general anesthesia (GA) alone. Methods: Two hundred and seventeen CS patients were divided into two groups. The GA group included 108 patients (age: 56±1 years, 66 males) and the SA group included 109 patients (age: 60±13 years, 55 males). Patients were weaned from MV and, after clinical evaluation, extubated. Results: In the SA group, considering a 13-month period, 24% of the patients were extubated in the operating room (OR), compared to 10% in the GA group (P=0.00). The OIT was lower in the SA group than in the GA group (SA: 4.4±5.9 hours vs. GA: 6.0±5.6 hours, P=0.04). In July/2017, where all surgeries were performed in the GA regimen, only 7.1% of the patients were extubated in the OR. In July/2018, 94% of the surgeries were performed under SA, and 64.7% of the patients were extubated in the OR (P=0.00). The OIT on arrival at the intensive care unit to extubation, comparing July/2017 to July/2018, was 5.3±5.3 hours in the GA group vs. 1.7±3.9 hours in the SA group (P=0.04). Conclusion: The adoption of SA in CS increased the frequency of extubations in the OR and decreased OIT and MV time.

Anestesia espinal parte IV. Técnica de la anestesia espinal y sus variaciones / Spinal anesthesia part IV. Spinal anesthesia technique and its variations

Spinal anesthesia is a very important and widely used technique nowadays. In order to obtain successful results and avoid complications, it is essential to perform it with the correct methods. The operator must be familiar with the procedure and prepare correctly for it, including material and drug selections which may vary according to the patient. Risk reduction is fundamental, and it is accomplished by carrying out the previously mentioned preparation and an adequate monitorization of the patient being intervened. Once this is in order, the patient must be positioned into being sited, or placed in supine or lateral position. The chosen approach depends mainly on the characteristics of anatomical repairs and may be medial, paramedian or a Taylor approach. The correct needle must be selected, and these are categorized mainly into those which cut or separate the dura's fibers. In this revision, the correct technique for performing spinal anesthesia is described, along with some of its most important variations such as sectorized anesthesia, continuous spinal anesthesia and combined epidural spinal anesthesia.

La anestesia espinal es una técnica ampliamente utilizada hoy en día. Para obtener resultados exitosos y evitar complicaciones, es fundamental una buena técnica a la hora de realizarla. Debe contarse con un buen conocimiento basal del método a utilizar y una preparación adecuada según el paciente, incluyendo en esto tanto los materiales como los fármacos de elección en cada caso. Es fundamental reducir los riesgos tanto locales como sistémicos del procedimiento, lo cual se logra con la preparación mencionada y una adecuada monitorización del paciente. Una vez listo esto, debe posicionarse al paciente de manera que quede sentado, en decúbito lateral o decúbito prono. El abordaje es elegido principalmente según los reparos anatómicos de cada caso particular y puede ser medio, paramediano o de Taylor. Se debe seleccionar una aguja adecuada, las cuales se dividen principalmente entre aquellas que cortan y aquellas que separan las fibras de la duramadre. En esta revisión se expone la técnica adecuada para realizar el procedimiento de anestesia espinal, junto con algunas de sus variaciones principales como lo son la anestesia sectorizada, la anestesia espinal continua y la anestesia combinada espinal epidural.

Anestesia espinal parte III. Mecanismos de acción / Spinal anesthesia part III. Mechanisms of action

Spinal anesthesia is a widely used technique in medical practice nowadays. Generally, nervous blockage is determined by three main factors. The first of them is the distribution of the local anesthetic in the cerebrospinal fluid (CSF), which can be affected by numerous factors, the most important of them being CSF volume. The second is absorption, which is greatest at the sites with higher drug concentration: this is the result of the accessibility, lipidic content and vascular irrigation of each area. The last of these factors is elimination, mediated mainly by the irrigation of the different compartments, and whose order differs from the mirror image of the onset's action order. The previously mentioned elements are the main sources of variation for the time needed to achieve desired effects, order in which fibers are affected and differential blockage. This text describes the principal mechanisms through which spinal anesthesia works, and the factors which can result in variations of its results.

La anestesia espinal es una técnica ampliamente utilizada en la práctica clínica. Por lo general, el bloqueo nervioso está determinado por tres factores principales. El primero es la distribución del anestésico local en el líquido cefalorraquídeo (LCR), que a su vez se ve afectado por una gran variedad de factores, destacando entre estos el volumen de LCR. El segundo es la absorción, la cual es mayor en los sitios en donde la concentración del fármaco también lo es: para esto afecta la accesibilidad, el contenido lipídico y la irrigación vascular de cada zona. El último factor es la eliminación, mediada principalmente por la irrigación de los distintos compartimentos, y cuyo orden es distinto a la imagen especular del inicio de acción. Los factores mencionados son los principales determinantes de los tiempos de demora de los bloqueos, el orden en el que se logra su acción en las distintas fibras y el bloqueo diferencial. Este texto pretende describir los principales mecanismos de acción mediante los cuales actúa la anestesia espinal y los factores que pueden determinar diferencias en los resultados de esta.

¿Puede el fentanilo intratecal disminuir la aparición de náuseas y vómito en comparación con ondansetrón intravenoso durante cesárea electiva? Revisión sistemática de la literatura y metaanálisis / Can intrathecal fentanyl decrease the occurrence of nausea and vomiting compared with intravenous ondansetron during elective cesarean section? Literature Systematic review and meta-analysis

Elective caesarean section is one of the surgeries with the highest intraoperative incidence of nausea, retching and vomiting (IONV), due, among other causes, to the use of anesthetics during the procedure. Some clinical trials have associated the use of low-dose intrathecal (IT) fentanyl with a lower incidence of nausea, retching and vomiting compared to other anesthetics used during caesarean sections. In this context, the objective of this meta-analysis was to evaluate the decrease in the appearance of nausea and vomiting during elective caesarean section with the application of IT fentanyl when compared with the use of intravenous ondansetron (EV). A systematic search was conducted in the main databases (PubMed, EMBASE, ClinicalTrials.gov, Cochrane Library and Google Scholar) for Randomized Clinical Trials (RCTs) that evaluated the use of IT fentanyl compared to ondansetron EV to decrease the occurrence and incidence of IONV during elective caesarean section. The meta-analysis showed a reduction in the incidence of nausea (RR 0.52, 95% CI 0.29-0.93, P = 0.03), gagging (RR 0.39, 95% CI 0, 18-0.88, P = 0.02) and vomiting (RR 0.26, 95% CI 0.11-0.64, P = 0.003) in the group of patients treated with IT fentanyl compared to the group treated with EV ondansetron. From the results, it is suggested that the administration of 12.5 to 20 µg of IT fentanyl may decrease the incidence of IONV in patients undergoing elective caesarean section, although the importance of more high-quality RCTs is highlighted.

La cesárea electiva es una de las cirugías con mayor incidencia intraoperatoria de náuseas, arcadas y vómito (NAV), debido entre otras causas, al uso de anestésicos durante el procedimiento. Algunos ensayos clínicos han asociado el uso de fentanilo intratecal (IT) a dosis bajas con una menor incidencia de náuseas, arcadas y vómito en comparación con otros anestésicos usados durante las cesáreas. En este contexto el objetivo de este metaanálisis fue evaluar la disminución en la aparición de náuseas y vómito durante cesárea electiva con la aplicación de fentanilo IT al compararlo con el uso de ondansetrón intravenoso (EV). Se realizó una búsqueda sistemática en las principales bases de datos (PubMed, EMBASE, ClinicalTrials.gov, Cochrane Library y Google Scholar) para ensayos clínicos aleatorizados (ECA) que evaluaron el uso del fentanilo IT en comparación con ondansetrón EV para disminuir la aparición e incidencia de IONV durante cesárea electiva. En el metaanálisis se evidenció una reducción en la incidencia de náusea (RR 0,52, 95% IC 0,29-0,93, P = 0,03), arcada (RR 0,39, 95% IC 0,18-0,88, P = 0,02) y vómito (RR 0,26, 95% IC 0,11-0,64, P = 0,003) en el grupo de pacientes tratados con fentanilo IT comparado con el grupo tratado con ondansetrón EV. A partir de los resultados, se sugiere que la administración de 12,5 a 20 µg de fentanilo IT puede disminuir la incidencia de NAV intraoperatorias en pacientes sometidas a cesárea electiva, aunque se resalta la importancia de más ECA de alta calidad.

Alcohol (70%) versus alcoholic chlorhexidine solution (0. 5%) in skin antisepsis for neuraxial blocks: a randomized clinical trial / Álcool 70% versus solução alcoólica de clorexidina 0, 5% na antissepsia da pele para bloqueios do neuroeixo: ensaio clínico randomizado

ABSTRACT Objective: to compare the use of 0.5% alcoholic chlorhexidine and 70% alcohol in skin antisepsis for neuraxial blocks. Method: this is a non-inferiority randomized clinical trial, with two parallel arms. Seventy patients who were candidates for neuraxial block were randomly allocated to group A (n = 35), in whom antisepsis was performed with 0.5% alcoholic chlorhexidine, or to group B (n = 35), in whom we used 70% hydrated ethyl alcohol. Swabs were harvested for culture at three times: before antisepsis, two minutes after application of the antiseptic, and immediately after puncture. The samples were sown in three culture media and the number of colony forming units (CFU) per cm² was counted. Results: there was no difference between the groups regarding age, sex, body mass index, time to perform the block or type of block. There were no differences between groups in the CFU/cm² counts before antisepsis. There was less bacterial growth in group B two minutes after application of the antiseptic (p = 0.048), but there was no difference between the groups regarding the number of CFU/cm² at the end of the puncture. Conclusion: 70% alcohol was more effective in reducing the number of CFU/cm² after two minutes, and there was no difference between the two groups regarding skin colonization at the end of the procedure. These results suggest that 70% alcohol may be an option for skin antisepsis before neuraxial blocks. Trial registration: ClinicalTrials.gov, NCT02833376.

RESUMO Objetivo: comparar o uso de solução alcoólica de clorexidina 0,5% e de álcool 70% na antissepsia da pele para bloqueios do neuroeixo. Método: ensaio clínico randomizado de não inferioridade, com dois braços paralelos. Foram selecionados 70 pacientes candidatos à bloqueio do neuroeixo, randomicamente alocados para o grupo A (n=35), em que a antissepsia foi realizada com clorexidina alcoólica 0,5%, ou para o grupo B (n=35), em que se utilizou álcool etílico hidratado 70%. Foram coletadas, com swab, amostras para cultura em três momentos: antes da antissepsia, dois minutos após aplicação do antisséptico, e imediatamente após a punção. As amostras foram semeadas em três meios de cultura e foi contabilizado o número de unidades formadoras de colônias (UFC) por cm². Resultados: não houve diferença entre os grupos quanto à idade, ao sexo, ao índice de massa corporal, ao tempo para realização do bloqueio ou tipo de bloqueio. Também não houve diferenças entre os grupos na contagem de UFC/cm² antes da antissepsia. Constatou-se menor crescimento bacteriano no grupo B dois minutos após aplicação do antisséptico (p=0,048), mas não houve diferença entre os grupos quanto ao número de UFC/cm² ao final da punção. Conclusão: o álcool 70% mostrou-se mais efetivo em reduzir o número de UFC/cm² após dois minutos, e não houve diferença entre os dois grupos quanto à colonização da pele ao final do procedimento. Esses resultados sugerem que o álcool 70% pode ser opção para antissepsia da pele antes de bloqueios do neuroeixo. Registro ensaio clínico: ClinicalTrials.gov, NCT02833376.

Effects of colloid preload on the incidence of hypotension in spinal anesthesia for cesarean section: a systematic review and meta-analysis / 中华医学杂志(英文版)

BACKGROUND@#Hypotension is a common complication caused by spinal anesthesia (SA), which may have adverse impacts on the condition of the parturient and fetus. Liquid infusion was found to be relatively effective for reducing the incidence of hypotension. However, the question of whether colloid preload can optimize hemodynamic variables in the cesarean section remains controversial. This study aims to determine the effects of colloid preload on the incidence of hypotension induced by SA in elective cesarean section.@*METHODS@#Related keywords were searched on PubMed, EMBASE, and Cochrane Library from inception dates to May 2020. Studies included were evaluated for eligibility and quality. The primary outcome was the intra-operative incidence of hypotension and severe hypotension. The secondary outcomes included the lowest intra-operative systolic blood pressure, the maximal intra-operative heart rate, the intra-operative needs of ephedrine and phenylephrine, the incidence of maternal nausea and/or vomiting, and neonatal outcomes (umbilical artery pH and Apgar scores). Apart from the above, RevMan 5.3 was used for the data analysis.@*RESULTS@#Altogether nine randomized controlled trials were included in the meta-analysis. There were no significant differences in the incidence of intra-operative hypotension, severe hypotension, or neonatal outcomes between the colloid preload group and control group, except for the umbilical artery pH.@*CONCLUSION@#This meta-analysis suggests that colloid preload does not significantly reduce the incidence of hypotension associated with SA in elective cesarean section.