Intraoperative effects of an alveolar recruitment manoeuvre in patients undergoing laparoscopic colon surgery.

INTRODUCTION: Pulmonary atelectasis is common in patients undergoing laparoscopic abdominal surgery under general anaesthesia, which increases the risk of perioperative respiratory complications. Alveolar recruitment manoeuvres (ARM) are used to open up the lung parenchyma with atelectasis, although the duration of their benefit has not been clearly established. The aim of this study was to determine the effectiveness of an ARM in laparoscopic colon surgery, the duration of response over time, and its haemodynamic impact. METHODS: Twenty-five patients undergoing laparoscopic colon surgery were included. After anaesthetic induction and initiation of surgery with pneumoperitoneum, an ARM was performed, and then optimal PEEP determined. Respiratory mechanics and gas exchange variables, and haemodynamic parameters, were analysed before the manoeuvre and periodically over the following 90 min. RESULTS: Three patients were excluded for surgical reasons. The alveolar arterial oxygen gradient went from 94.3 (62.3-117.8) mmHg before to 60.7 (29.6-91.0) mmHg after the manoeuvre (P < .05). This difference was maintained during the 90 min of the study. Dynamic compliance of the respiratory system went from 31.3 ml/cmH2O (26.1-39.2) before the manoeuvre to 46.1 ml/cmH2O (37.5-53.5) after the manoeuvre (P < .05). This difference was maintained for 60 min. No significant changes were identified in any of the haemodynamic variables studied. CONCLUSION: In patients undergoing laparoscopic colon surgery, performing an intraoperative ARM improves the mechanics of the respiratory system and oxygenation, without associated haemodynamic compromise. The benefit of these manoeuvres lasts for at least one hour.

Efectos intraoperatorios de una maniobra de reclutamiento alveolar en pacientes sometidos a cirugía laparoscópica de colon / Intraoperative effects of an alveolar recruitment manoeuvre in patients undergoing laparoscopic colon surgery

Introducción: Las atelectasias pulmonares son habituales en pacientes sometidos a cirugía abdominal laparoscópica bajo anestesia general, aumentando el riesgo de complicaciones respiratorias perioperatorias. Las maniobras de reclutamiento alveolar (MRA) permiten la reexpansión del parénquima atelectasiado, aunque no está claramente establecida la duración de su beneficio. El objetivo de este estudio fue determinar la efectividad de una MRA en cirugía de colon laparoscópica, la duración de la respuesta en el tiempo y su repercusión hemodinámica. Métodos: Se incluyeron 25 pacientes sometidos a cirugía de colon laparoscópica. Tras la inducción anestésica e inicio de la cirugía con neumoperitoneo, se realizó una MRA y determinación posterior de la PEEP óptima. Se analizaron variables de mecánica respiratoria y de intercambio gaseoso, así como parámetros hemodinámicos, antes de la maniobra y periódicamente durante los 90 min siguientes. Resultados: Tres pacientes fueron excluidos por causas quirúrgicas. El gradiente alveoloarterial de oxígeno pasó de 94,3 (62,3-117,8) mmHg antes a 60,7 (29,6-91,0) mmHg después de la maniobra (p < 0,05). Esta diferencia se mantuvo durante los 90 min del estudio. La compliance dinámica del sistema respiratorio pasó de 31,3 mL/cmH2O (26,1-39,2) antes de la maniobra, a 46,1 mL/cmH2O (37,5-53,5) tras la misma (p < 0,05). Esta diferencia se mantuvo durante 60 min. No se identificaron cambios significativos en ninguna de las variables hemodinámicas estudiadas. Conclusión: En pacientes sometidos a cirugía laparoscópica de colon, la realización de una MRA intraoperatoria mejora la mecánica del sistema respiratorio y la oxigenación, sin apreciarse un compromiso hemodinámico asociado. El beneficio de estas maniobras se extiende al menos durante una hora.(AU)

Introduction: Pulmonary atelectasis is common in patients undergoing laparoscopic abdominal surgery under general anaesthesia, which increases the risk of perioperative respiratory complications. Alveolar recruitment manoeuvres (ARM) are used to open up the lung parenchyma with atelectasis, although the duration of their benefit has not been clearly established. The aim of this study was to determine the effectiveness of an ARM in laparoscopic colon surgery, the duration of response over time, and its haemodynamic impact. Methods: Twenty-five patients undergoing laparoscopic colon surgery were included. After anaesthetic induction and initiation of surgery with pneumoperitoneum, an ARM was performed, and then optimal PEEP determined. Respiratory mechanics and gas exchange variables, and haemodynamic parameters, were analysed before the manoeuvre and periodically over the following 90 minutes. Results: Three patients were excluded for surgical reasons. The alveolar arterial oxygen gradient went from 94.3 (62.3-117.8) mmHg before to 60.7 (29.6-91.0) mmHg after the manoeuvre (P < .05). This difference was maintained during the 90 minutes of the study. Dynamic compliance of the respiratory system went from 31.3 ml/cmH2O (26.1-39.2) before the manoeuvre to 46.1 ml/cmH2O (37.5-53.5) after the manoeuvre (P < .05). This difference was maintained for 60 minutes. No significant changes were identified in any of the haemodynamic variables studied. Conclusion: In patients undergoing laparoscopic colon surgery, performing an intraoperative ARM improves the mechanics of the respiratory system and oxygenation, without associated haemodynamic compromise. The benefit of these manoeuvres lasts for at least one hour.(AU)

Late bilateral vocal cord palsy following endotracheal intubation due to COVID-19 pneumonia.

Vocal cord paralysis is a rare but severe complication after orotracheal intubation. The most common cause is traumatic, due to compression of the recurrent laryngeal nerve between the orotracheal tube cuff and the thyroid cartilage. Other possible causes are direct damage to the vocal cords during intubation, dislocation of the arytenoid cartilages, or infections, especially viral infections. It is usually due to a recurrent laryngeal nerve neuropraxia, and the course is benign in most patients. We present the case of a man who developed late bilateral vocal cord paralysis after pneumonia complicated with respiratory distress due to SARS-CoV-2 that required orotracheal intubation for 11 days. He presented symptoms of dyspnea 20 days after discharge from hospital with subsequent development of stridor, requiring a tracheostomy. Due to the temporal evolution, a possible contribution of the SARS-CoV-2 infection to the picture is pointed out.

Parálisis bilateral tardía de cuerdas vocales trasintubación endotraqueal por neumonía COVID-19 / Late bilateral vocal cord palsy following endotracheal intubation due to COVID-19 pneumonia

La parálisis de cuerdas vocales es una complicación poco frecuente, aunque severa, tras una intubación orotraqueal. La causa más frecuente es la traumática, debido a la compresión del nervio laríngeo recurrente entre el maguito del tubo orotraqueal y el cartílago tiroides. Otras posibles causas son lesión directa de las cuerdas vocales durante la intubación, luxación de los cartílagos aritenoides e infecciones, sobre todo víricas. Suele deberse a una neuroapraxia del nervio laríngeo recurrente, y el curso es benigno en la mayoría de los pacientes. Presentamos el caso de un varón que desarrolló una parálisis de cuerdas vocales bilateral tras una neumonía complicada con distrés respiratorio por SARS-CoV-2 que requirió intubación orotraqueal durante 11 días. Presentó clínica de disnea a los 20 días del alta hospitalaria con desarrollo posterior de estridor, siendo necesaria la realización de una traqueostomía. Debido a la evoución temporal, se apunta una posible contribución de la infección por SARS-CoV-2 al cuadro.(AU)

Vocal cord paralysis is a rare but severe complication after orotracheal intubation. The most common cause is traumatic, due to compression of the recurrent laryngeal nerve between the orotracheal tube cuff and the thyroid cartilage. Other possible causes are direct damage to the vocal cords during intubation, dislocation of the arytenoid cartilages, or infections, especially viral infections. It is usually due to a recurrent laryngeal nerve neuropraxia, and the course is benign in most patients. We present the case of a man who developed late bilateral vocal cord paralysis after pneumonia complicated with respiratory distress due to SARS-CoV-2 that required orotracheal intubation for 11 days. He presented symptoms of dyspnea 20 days after discharge from hospital with subsequent development of stridor, requiring a tracheostomy. Due to the temporal evolution, a possible contribution of the SARS-CoV- 2 infection to the picture is pointed out.(AU)

Late bilateral vocal cord palsy following endotracheal intubation due to COVID-19 pneumonia. / Parálisis bilateral tardía de cuerdas vocales trasintubación endotraqueal por neumonía COVID-19.

Vocal cord paralysis is a rare but severe complication after orotracheal intubation. The most common cause is traumatic, due to compression of the recurrent laryngeal nerve between the orotracheal tube cuff and the thyroid cartilage. Other possible causes are direct damage to the vocal cords during intubation, dislocation of the arytenoid cartilages, or infections, especially viral infections. It is usually due to a recurrent laryngeal nerve neuropraxia, and the course is benign in most patients. We present the case of a man who developed late bilateral vocal cord paralysis after pneumonia complicated with respiratory distress due to SARS-CoV-2 that required orotracheal intubation for 11 days. He presented symptoms of dyspnea 20 days after discharge from hospital with subsequent development of stridor, requiring a tracheostomy. Due to the temporal evolution, a possible contribution of the SARS-CoV- 2 infection to the picture is pointed out.

Efecto del opioide intradural en bloqueos selectivos espinales en cirugía artroscópica de rodilla ambulatoria / Effect of intrathecal opioid in selective spinal anesthesia for outpatients undergoing knee arthroscopic surgery

INTRODUCCIÓN: Recientemente numerosos estudios demostraron que la realización de bloqueos espinales selectivos genera mayor estabilidad hemodinámica y mayor selectividad en el control de la agresión quirúrgica. OBJETIVO: Evaluar la influencia de la asociación de fentanilo a anestésicos locales administrados por vía intradural en bloqueos espinales selectivos en CMA.MATERIAL Y MÉTODOS: Estudio prospectivo, randomizado de 60 pacientes ASA I - III, programados para cirugía artroscópica de rodilla. Los pacientes se dividen en dos grupos; Grupo A: 5 mg (1ml) de bupivacaína 0,5% hiperbara. Grupo B: 5 mg (1ml) de bupivacaína 0,5% hiperbara asociado a 10 mg de fentanilo. La anestesiaintradural se realizó en decúbito lateral con aguja25 G en el espacio L2-L3, inyectando la solución anestésica en un 1 minuto y manteniéndose en esa posición durante 20 minutos. Se considera fracaso de la técnica si L1-L3 no se bloquean tras20 minutos y no se incluyen en el estudio pacientes con peso superior a 70 Kg. El bloqueo sensitivo se evaluó mediante la técnica de pinchazo y frío-calor y el bloqueo motor mediante la escala de Bromage modificada. RESULTADOS: No existen diferencias en las características demográficas, ASA, ni duración de la cirugía. Las complicaciones fueron mayores en el grupo B, sin existir diferencias en los tiempos de recuperación. CONCLUSIÓN: La asociación de fentanilo a anestésicos locales no modificó cualitativamente el bloqueo espinal selectivo, sin embargo la incidencia de efectos secundarios fue significativamente superior (AU)

INTRODUCTION: Many studies have recently demostrated that selective spinal blocks provide better control of surgical aggression with increased hemodynamic stability. OBJECTIVES: To assess the influence of intrathecalfentanyl added to a local anesthetic in selectivespinal anesthesia in the outpatient setting. METHODS: A prospective study, in which 60patients ASA I-III undergoing ambulatory surgical arthroscopy were randomly divided into two groups: Group A: 5 mg hyperbaric 0.5 % bupivacaine(1ml) and Group B: 5 mg hyperbaric 0.5 % bupivacaine (1ml) with the addition of 10 mg fentanyl. The subarachnoid anesthesia was performed in the lateral decubitus position with a 25 gauge pencil-point needle at the L2-L3 ( ..) (AU)

Infarto agudo de miocardio en el perioperatorio de una neumonectomía / Perioperative acute myocardial infarction during a pneumonectomy

A un varón de 71 años con diabetes insulino-dependiente, hábito tabáquico y dislipemia se le realizó una neumonectomía izquierda. Durante el período intraoperatorio se produjeron varios episodios de inestabilidad hemodinámica asociados a cambios en el segmento ST del ECG que se justificaron por la manipulación quirúrgica no sospechándose la posibilidad de un origen isquémico. A los pocos minutos de su ingreso en la Unidad de Reanimación se produjo una parada cardiorrespiratoria, por infarto anterior extenso, que precisó ventilación mecánica y maniobras de reanimación cardiopulmonar. El paciente evolucionó favorablemente y respondió al tratamiento con betabloqueantes, antiagregantes plaquetarios y estatinas. A las pocas horas se extubó y pudo ser dado de alta de la Unidad de Reanimación a los 5 días. La neumonectomía es una cirugía con elevado índice de morbimortalidad, siendo las complicaciones de origen pulmonar y cardíaco las principales responsables. Se considera un procedimiento de elevado riesgo anestésico, razón por la cual la identificación de isquemia miocárdica durante el período intraoperatorio es fundamental para tratarla agresivamente. En pacientes de elevado riesgo cardiovascular, que se someten a cirugía de resección pulmonar, la presencia de episodios de isquemia miocárdica intraoperatoria se asocian con una incidencia elevada de eventos isquémicos postoperatorios y, por tanto, debería condicionar una monitorización agresiva postoperatoria, medidas antianginosas y evitar la extubación precoz (AU)

[Acute myocardial infarction in the postoperative period following pneumonectomy]. / Infarto agudo de miocardio en el perioperatorio de una neumonectomía.

A 72-year-old man, smoker, with insuline-dependent diabetes and dislipemia underwent left pneumonectomy. Several episodes of intraoperative hemodynamic instability associated with electrocardiographic ST segment alterations were attributed to surgical manipulation; ischemia was not suspected. Cardiorespiratory failure, related to extensive anterior infarction, developed a few minutes after admission to the postoperative intensive care unit (PICU). Cardiopulmonary resuscitation and mechanical ventilation were required. The patient responded to treatment with beta blockers, platelet antiaggregants and statins. Tube was removed a few hours later and the patient was discharged from the PICU on the fifth day. Pneumonectomy has a high rate of morbidity and mortality, with complications mainly arising in the lung and heart. Risk from anesthesia is considered to be great in this procedure, and for that reason it is essential to identify intraoperative myocardial ischemia so that it can be treated aggressively. In patients at high cardiovascular risk who undergo lung resection, intraoperative episodes of myocardial ischemia are associated with a high incidence of postoperative miocardial infarction. Therefore, careful postoperative monitoring is needed and measures should be taken to prevent angina. Early extubation should be avoided.

[The effect of propofol vs desflurane on recovery from anesthesia with remifentanil in outpatient surgery]. / Repercusión en la recuperación postanestésica de propofol frente a desflurano asociados a remifentanilo en cirugía ambulatoria.

OBJECTIVES: To compare the effect on parameters of postanesthetic recovery of propofol and desflurane administered with high doses of remifentanil for major outpatient surgery. PATIENTS AND METHODS: Seventy patients were randomly assigned to receive propofol (target concentration 1.5-2 microg/ml) or desflurane in perfusion (end expiratory concentration 0.5 MAC) during maintenance of anesthesia with remifentanil (0.25-1 microg/kg/min). The anesthetic agents were withdrawn after surgery. We recorded the times until eye opening, respiration, tracheal extubation, ability to cough, response to verbal orders and orientation. We also recorded the time until a score of 10 on the Aldrete recovery scale was attained, pain on a visual analog scale, sedation on the Ramsay scale, and instances of nausea or vomiting during the first 24 h after surgery. RESULTS: No statistically significant differences in patient characteristics, type of surgery or anesthesia were found. Times until early signs of postanesthetic recovery (eye opening, spontaneous breathing, tracheal extubation) were significantly less (p < 0.05) in the desflurane group. The groups were similar for all other parameters compared (times until ability to cough, respond to verbal orders, orientation and a score of 10 on the Aldrete scale). Duration of stay in the postanesthetic recovery unit, time in the day surgery ward and intensity of postoperative pain were also similar. The rate of postoperative nausea or vomiting was significantly lower in the propofol group. CONCLUSION: During anesthesia with remifentanil, the administration of desflurane is associated with better psychomotor recovery parameters than is propofol, but the rate of nausea and vomiting is higher with desflurane.

Repercusión en la recuperación postanestésica de propofol frente a desflurano asociados a remifentanilo en cirugía ambulatoria / The effect of propofol or desflurane on recovery from anesthesia with remifentanil for outpatient surgery

OBJETIVOS. Comparar la repercusión en parámetros de recuperación postanestésica de dos agentes anestésicos, propofol y desflurano, cuando se administran asociados a dosis elevadas de remifentanilo en cirugía mayor ambulatoria (CMA). PACIENTES Y MÉTODOS. Se incluyó a 70 pacientes para recibir de forma aleatoria propofol en perfusión (concentración TCI diana de 1,5-2 µg/ml) o desflurano (concentración teleinspiratoria de 0,5 CAM) durante el mantenimiento anestésico con remifentanilo (0,25-1 µg/kg/min). Al final de la intervención se suprimieron los agentes anestésicos y se registró el tiempo hasta la apertura de ojos, la ventilación espontánea, la extubación traqueal, la capacidad de toser, la respuesta a órdenes verbales y la orientación temporoespacial, así como el tiempo que tardaban en alcanzar una puntuación de 10 en la escala de recuperación de Aldrete, la intensidad del dolor postoperatorio mediante escala visual analógica, el grado de sedación según escala Ramsay y la incidencia de náuseas y vómitos postoperatorios durante las primeras 24 h. RESULTADOS. No existieron diferencias estadísticamente significativas entre ambos grupos respecto a las características demográficas y anestesicoquirúrgicas. Los parámetros de recuperación postanestésica tempranos (apertura de ojos, ventilación espontánea, extubación traqueal) fueron significativamente menores (p < 0,05) en el grupo desflurano, sin existir significación estadística en el resto de los parámetros comparados (capacidad de toser, respuesta a órdenes verbales, orientación temporoespacial y puntuación de 10 en la escala de Aldrete). Tampoco existieron diferencias con respecto a los tiempos de estancia en la unidad de recuperación postanestésica (URPA) y la sala de deambulación, ni en lo referente al dolor postoperatorio. En el grupo propofol la incidencia de náuseas y vómitos postoperatorios fue significativamente menor. CONCLUSIÓN. La anestesia basada en remifentanilo y desflurano proporciona unos parámetros de recuperación psicomotriz superiores al propofol, pero con una mayor incidencia de náuseas y vómitos (AU)

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[Malignant hyperthermia in a pig anesthesized with desflurane]. / Hipertermia maligna en un cerdo anestesiado con desflurano.

A large-white pig that had not been genetically selected to develop malignant hyperthermia (MH) during anesthesia nevertheless suffered an episode of severe MH after repeated exposure to increasing concentrations of desflurane. MH is a hypermetabolic alteration that may develop in susceptible patients who have inhaled certain drugs or agents that act as triggers. Early identification and appropriate treatment are essential to reduce the likelihood of death associated with this severe alteration. We report a case of late-developing MH triggered by low concentrations of inhaled desflurane.

Hipertermia maligna en un cerdo anestesiado con desflurano / Malignant hyperthermia in a pig anesthestized with desflurane

Un cerdo de la raza Large-White, no seleccionado genéticamente para desarrollar hipertermia maligna (HM) durante la anestesia, presentó un episodio de hipertermia maligna grave tras la exposición repetida a concentraciones crecientes con desflurano.La hipertermia maligna es una alteración hipermetabólica que se puede presentar en pacientes susceptibles a los que se le administran ciertos fármacos o agentes inhalatorios que actúan como agentes desencadenantes. La identificación precoz y el tratamiento adecuado son imprescindibles para disminuir la mortalidad asociada a tan grave alteración.Este caso de hipertermia maligna desencadenado por desflurano se caracterizó por una presentación tardía y por desarrollarse con una concentración mínima de agente inhalatorio (AU)

Low-flow anesthesia and reduced animal size increase carboxyhemoglobin levels in swine during desflurane and isoflurane breakdown in dried soda lime.

UNLABELLED: After institutional approval, we studied the effect of animal size, anesthetic concentration, and fresh gas flow (FGF) rate on inspired carbon monoxide (CO) and carboxyhemoglobin (COHb) during anesthesia in swine, using soda lime previously dried to 1 +/- 0.1% water content. To ascertain the effect of anesthesia, eight adult pigs were anesthetized with either 1 minimum alveolar anesthetic concentration (MAC) desflurane or isoflurane and, to characterize the effect of the FGF rate, it was doubled in four pigs. To determine the effect of animal size, four small and four large pigs received 1 MAC desflurane or isoflurane, and to determine the effect of the anesthetic concentration, a group of four swine was exposed to 0.5 MAC. CO and COHb concentrations were larger with desflurane (5500 +/- 980 ppm and 57.90% +/- 0.50%, respectively) than with isoflurane (800 ppm and 17.8% +/- 2.14%, respectively), especially in the small animals. Increasing the FGF rate significantly reduced peak CO and COHb concentrations resulting from both anesthetics; however, when each anesthetic was reduced to 0.5 MAC, the concentrations obtained were similar. We conclude that CO intoxication is more severe with desflurane than with isoflurane, that small animals are at higher risk for CO poisoning, and that low FGF can increase COHb concentrations. IMPLICATIONS: The present study shows that the use of desflurane with desiccated carbon dioxide absorbents in pediatric anesthesia can produce a dangerous carbon dioxide intoxication, especially with low-flow anesthesia.

[Epidural abscess secondary to the implantation of a thoracic catheter]. / Absceso epidural secundario a la implantación de un catéter torácico.

Spinal compression related to the formation of an epidural abscess after epidural blockade is a rare but serious complication. We report the case of a male patient in whom a thoracic epidural catheter was implanted to provide analgesia after trauma involving fracture ribs. The patient developed an epidural abscess within one week of implantation. Delay in diagnosis led to persistent neurogenic bladder symptoms in spite of aggressive treatment. We review causal factors, mechanisms of formation, pathogenesis, diagnosis and management, as well as possible relation between injury and abscess formation. We also emphasize the importance of adequate vigilance as well as rapid diagnosis and adoption of therapeutic measures in order to avoid permanent sequelae such as paresis, sensory deficits or mechanical sphincter dysfunction.

[Quantification of dehydration of soda lime in clinical circumstances]. / Cuantificación de la desecación de la cal sodada en circunstancias clínicas.

HYPOTHESIS AND OBJECTIVES: When the CO2 absorbents, soda lime and baralime, have lost their normal level of hydration, they may react with certain halogenated anesthetics to produce appreciable levels of carbon monoxide. The degree of absorbent desiccation has been considered the limiting factor for this phenomenon. This study quantifies the level of dehydration of lime produced under clinical conditions and the influence of several factors. MATERIAL AND METHOD: Desiccation was determined: 1) at set periods of time (3, 7 and 14 days) after clinical use of fresh soda lime in general anesthesia using a fresh gas flow (FGF) of 6 l/min, and 2) after gas had been crossing the continuous flow (CF) oxygen reservoir at 7 l/min for 17 and 65 hours. Two anesthetic systems were used: a) the Ohmeda Excel-210, in which the continuous FGF did not cross the reservoir and b) the Siemens Ventilator 710, in which the FGF did cross the reservoir. The experiments were repeated with three types of lime. RESULTS: The clinical use of lime for 3, 7 and 14 days caused different levels of desiccation, with decreases in hydration of up to 50% and 14 days. Nevertheless, water content was always over 5%, a level at which no reaction with halogenated agents takes place. After 17 and 65 hours of CF in the circuit where continuous FGF did not pass through the canister, the water content did not change. With the Siemens 710 circuit, in which the continuous FGF crossed the canister, the dehydration level was 1.2 +/- 0.3% after 17 hours and 0.7 +/- 0.3% after 65 hours, a level that can produce CO upon reaction between lime and halogenated gases. The type of lime used had little effect. CONCLUSIONS: Lime does not desiccate to levels able to produce CO in daily use, regardless of the FGF system used. The phenomenon of desiccation depends on two factors: 1) use of anesthetic equipment in which continuous FGF conditions require gas to pass through the canister, and 2) the maintenance of CF for a sufficient period of time.

[Late paraparesis as a postoperative complication in a patient undergoing the repair of a double aortic aneurysm]. / Paraparesia tardía como complicación postoperatoria en paciente sometido a reparación de doble aneurisma aórtico.

We report a case of a fifty-seven (57)-years old man undergoing elective surgery of a thoracoabdominal and aortoiliac aneurysm in a single surgical time. The patients is operated undergoing general anesthetic combined with thoracic epidural blockade, and it was done two aortic cross-clamping: one to five cm of the aortic arch and the other to the infrarenal level. The most important intraoperative complications were during the thoracic aortic cross-clamping and the most important postoperative complication was related 48 hours later, to paraparesis after a hypotension episode what improved with rehabilitation treatment.