RESUMEN
BACKGROUND: Some patients have features that indicate possible difficulty with direct laryngoscopy for tracheal intubation. Prediction of the likely outcome and selection of patients for an enhanced management algorithm would reduce the possible harm from failed intubation attempts. METHODS: Adult elective patients were assessed for seven features associated with difficult direct laryngoscopy, ranked in difficulty from 0 to 3. For a patient with at least one Class 3 feature, or two or more features of class 1 or higher, the enhanced management used a channelled videolaryngoscope Airtraq™ instead of a Macintosh laryngoscope. A long flexible angulated stylet and a flexible fibrescope would be used as the second and third steps. For patients with lesser difficulty scores, a Macintosh laryngoscope was used. Outcomes of enhanced management were analysed. Logistic regression and Random Forest algorithm, using the ranks of the predictive features, were used to predict difficulty during enhanced management. RESULTS: We prospectively studied 16 695 patients. We selected 1501 (9%) for enhanced management, and tracheal intubation was successful in all of them. Of these, 73% were intubated in less than 30 s, and only 4.5% required more than 4 min for intubation. Progression to the second and third steps of enhanced management was predicted by restriction of mouth opening and reduced cervical spine mobility. CONCLUSIONS: An enhanced management algorithm allowed successful tracheal intubation of all patients with anticipated difficult laryngoscopy. The need to combine the use of a stylet and a fibrescope with the Airtraq™ could be predicted with a high degree of certainty.
Asunto(s)
Manejo de la Vía Aérea/métodos , Algoritmos , Intubación Intratraqueal/métodos , Adulto , Anciano , Manejo de la Vía Aérea/normas , Anestesia General , Vértebras Cervicales/anatomía & histología , Árboles de Decisión , Femenino , Humanos , Intubación Intratraqueal/normas , Laringoscopía , Masculino , Persona de Mediana Edad , Boca/anatomía & histología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Resultado del TratamientoRESUMEN
The aim of our study were to evaluate the prevalence of HR-HPV infection in women between 15 and 55 years of age in the South and Northern Bulgaria. We have analyzed the HPV status (using DNA-sorb-AM nucleic acid extraction kit) in cervical samples collected during a 3 year period (2010-2012) from 1020 women, aged 15-55 and divided in four age groups, who attended their gynecologists for HPV-DNA cervical test. The rate of the HR-HPV infection was established to be 39.9%. HR-HPV negative were 60.1% of the evaluated subjects. The most commonly isolated genotype in all 407 (100%) infected women was HPV 16 - 190 women (46.7%), followed by HPV 56 - 78 (19.1%), HPV 31- 48 (11.8%) and HPV 33 - 45 (11.1%). To our knowledge, this is the first survey evaluating the prevalence of HR-HPV infection in the South and Northern regions of Bulgarian towns and drawing attention to the unusually high proportion of different HR-HPV.
Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Adolescente , Adulto , Alphapapillomavirus/genética , Bulgaria/epidemiología , Femenino , Genotipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/aislamiento & purificación , Papillomavirus Humano 31/genética , Papillomavirus Humano 31/aislamiento & purificación , Humanos , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
We report the case of a patient who underwent third time revision of double heart valve replacement. Mediastinal dissection for right atrium cannulation was complicated by laceration of the superior vena cava; this required temporary rescue clamping of the vessel. The patient suffered complete visual loss related to bilateral retrobulbar haematoma. Acute elevation of superior vena cava pressure due to vascular clamping and administration of large amounts of fluid through the central venous jugular catheter could have caused the postoperative visual loss.
Asunto(s)
Ceguera/etiología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Hematoma/complicaciones , Hipotensión/complicaciones , Mediastino/cirugía , Complicaciones Posoperatorias/etiología , Constricción , Femenino , Fluidoterapia/métodos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Persona de Mediana Edad , Reoperación , Hemorragia Retrobulbar/complicaciones , Choque Hemorrágico/complicaciones , Tomografía Computarizada por Rayos X/métodos , Vena Cava Superior/lesionesRESUMEN
BACKGROUND: Because recovery of an efficient swallowing reflex is a determining factor for the recovery of airway protective reflexes, we have studied the influence of the tracheostomy tube cuff pressure (CP) on the swallowing reflex in tracheotomized patients. METHODS: Twelve conscious adult intensive care unit (ICU) patients who had been weaned from mechanical ventilation were studied. Simultaneous EMG of the submental muscles with measurement of peak activity (EMGp) and amplitude of laryngeal acceleration (ALA) were performed during reflex swallows elicited by pharyngeal injection of distilled water boluses during end expiration. After cuff deflation, characteristics of the swallowing reflex (latency time: LaT, EMGp, and ALA) were measured at CPs of 5, 10, 15, 20, 25, 30, 40, 50, and 60 cm H(2)O. RESULTS: LaT and CP were linearly related (P<0.01). CP was inversely correlated (P<0.01) to both ALA and EMGp. CONCLUSIONS: We demonstrated that LaT, EMGp, and ALA of the swallowing reflex were influenced by tracheostomy tube CP. The swallowing reflex was progressively more difficult to elicit with increasing CP and when activated, the resulting motor swallowing activity and efficiency at elevating the larynx were depressed.
Asunto(s)
Deglución/fisiología , Reflejo/fisiología , Traqueostomía , Acelerometría , Adulto , Sedación Consciente , Cuidados Críticos , Femenino , Contenido Digestivo , Escala de Coma de Glasgow , Humanos , Unidades de Cuidados Intensivos , Intubación Gastrointestinal , Masculino , Persona de Mediana Edad , Faringe/fisiología , Estimulación Física , Presión , Respiración Artificial , Mecánica Respiratoria/fisiología , Traumatismos Torácicos/terapia , Heridas no Penetrantes/terapia , Adulto JovenRESUMEN
INTRODUCTION: We have prospectively compared simulated-difficult tracheal intubation characteristics of four glottiscopes: Airtraq, GlideScope, McGrath, LMA CTrach with that of the conventional Macintosh laryngoscope. STUDY DESIGN: prospective with the airway devices proposed in a randomly assigned order. MATERIALS AND METHOD: Forty-two physicians, naïve to glottiscope handling accepted participating this study after the learning curve of each airway device was completed. Participants were requested to perform two series of five tracheal intubations on the manikin Airman, the first in standard situation and the second in difficult tracheal intubation simulation. The airway devices were chosen in a randomly assigned order. For each airway tool, the following tracheal intubation characteristics were recorded: laryngeal exposure quality, tracheal intubation and apnea durations. A performance index was calculated and a tracheal intubation difficulty was measured during simulation. RESULTS: More than 1600 supervised tracheal intubations were performed, including 1000 for the learning process of the glottiscopes, which was completed after 10 uses on the manikin. During standard situation, laryngeal exposure quality was similar with the five airway devices. As compared to the Macintosh laryngoscope, GlideScope, McGrath, tracheal intubation duration was shorter (p<0.05) with the Airtraq and longer (p<0.01) with the LMA CTrach. During difficult tracheal intubation simulation, laryngeal exposure and tracheal intubation duration was of better quality and shorter with the four glottiscopes as compared to that of LM, respectively. Performance index during difficult tracheal intubation simulation simulation was significantly more important (p<0.01) with the Airtraq and the LMA CTrach. Airtraq and Macintosh laryngoscope were respectively the simplest (p<0.01) and the most difficult (p<0.01) airway devices to manage a simulated difficult tracheal intubation. CONCLUSION: When difficult airway was simulated on the manikin, the four glottiscopes were superior to the Macintosh laryngoscope to improve laryngeal exposure quality and to reduce duration of tracheal intubation. Airtraq and the LMA CTrach both demonstrated remarkable advantage over GlideScope and McGrath for simulated difficult intubation management.
Asunto(s)
Glotis , Intubación Intratraqueal/métodos , Laringoscopios , Maniquíes , Diseño de Equipo , Humanos , Estudios ProspectivosRESUMEN
BACKGROUND: We designed a prospective randomized single-blind study to compare efficiency and post-operative upper airway morbidity when the laryngeal mask airway (LMA) Supreme is used as an alternative to the endotracheal tube (ETT). METHODS: One hundred and thirty-eight elective pelvic laparoscopic ASA I-II female patients were assigned to receive either the LMA Supreme or the ETT for airway management. Balanced anesthesia and ventilation techniques were standardized to control end-tidal CO(2) and BIS value in the range 4.5-5 kPa and 40-50, respectively, and to maintain adequate hemodynamic stability. A single surgeon blinded to the airway management technique performed all surgical procedures. The ventilation efficiency of each airway was evaluated. Anesthesia- and surgery-related times were calculated and anesthesia details were recorded. Post-operative pain and pharyngolaryngeal morbidity were measured in a blind fashion using a numerical rating scale (NRS) (0-100). RESULTS: Surgery duration was similar in both groups. Airway management duration was shorter with the LMA Supreme. Post-operative pharyngolaryngeal morbidity incidence and all symptoms' intensity were significantly increased after ETT as compared with LMA Supreme anesthesia. At the end of the PACU stage, the incidence and mean NRS of post-operative hoarseness were reduced when LMA Supreme was used as an alternative to the ETT (16% vs. 47%; P<0.01 and 9 vs. 19, P<0.01, respectively). CONCLUSION: We demonstrated that choosing an LMA Supreme was an efficient pharyngolaryngeal morbidity-sparing strategy. Moreover, we showed that the LMA Supreme and the ETT were equally effective airways for a routine gynecological laparoscopy procedure.
Asunto(s)
Procedimientos Quirúrgicos Ginecológicos , Intubación Intratraqueal/instrumentación , Laparoscopía , Enfermedades de la Laringe/prevención & control , Máscaras Laríngeas , Adulto , Anestesia General , Procedimientos Quirúrgicos Electivos , Femenino , Estudios de Seguimiento , Contenido Digestivo , Ronquera/etiología , Humanos , Enfermedades de la Laringe/etiología , Dimensión del Dolor , Dolor Postoperatorio/etiología , Enfermedades Faríngeas/etiología , Enfermedades Faríngeas/prevención & control , Faringitis/etiología , Complicaciones Posoperatorias , Estudios Prospectivos , Respiración , Método Simple Ciego , Estómago , Succión , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Because the intensity of neuromuscular block at the diaphragm (DIA) is indirectly assessed, the electromyographic measurements of the DIA (DIA(EMG)) from surface electrodes were related to information provided by visual estimation of neuromuscular transmission at the adductor pollicis (AP) and the corrugator supercilii (CSC) during recovery from vecuronium block. METHODS: Twelve adult patients were studied during balanced anaesthesia. After induction of anaesthesia and tracheal intubation without neuromuscular blocking agent, supramaximal stimulations were applied to phrenic, ulnar and facial nerves. During recovery from vecuronium 0.1 mg kg(-1) an independent observer blinded to DIA(EMG) counted visually detectable train-of-four (TOF) at CSC (TOF(CSC)) and post-tetanic AP (PTC(AP)) responses. Times to recovery of PTC(AP) = 1, Asunto(s)
Periodo de Recuperación de la Anestesia
, Diafragma/efectos de los fármacos
, Músculo Esquelético/efectos de los fármacos
, Fármacos Neuromusculares no Despolarizantes/farmacología
, Bromuro de Vecuronio/farmacología
, Adulto
, Anciano
, Diafragma/fisiología
, Estimulación Eléctrica/métodos
, Electromiografía/efectos de los fármacos
, Músculos Faciales/efectos de los fármacos
, Músculos Faciales/fisiología
, Femenino
, Humanos
, Masculino
, Persona de Mediana Edad
, Monitoreo Fisiológico/métodos
, Músculo Esquelético/fisiología
, Bloqueo Neuromuscular
, Unión Neuromuscular/efectos de los fármacos
, Cuidados Posoperatorios/métodos
, Método Simple Ciego
RESUMEN
Viruses have developed numerous strategies to escape recognition by the immune system. However, some viruses such as herpes simplex virus-2 (HSV-2) are recognized by initiators of the complement system, e.g. mannan-binding lectin (MBL). To study the effects of MBL deficiency during viral infection we have chosen a model of generalized HSV-2 infection. We infected MBL-A and MBL-C double knock-out mice (DKO) with HSV-2 via the intraperitoneal (i.p.) route. DKO mice cleared HSV-2 from the liver less efficiently than the comparable wild-type animals. The impairment to effectively neutralize HSV-2 correlated with compromised liver function as measured by increased plasma levels of alanine-amino transferase. No differences in the viral burden were found in other organs such as spleen or brain. Thus, MBL-mediated protection was limited to the effects of preservation of liver homeostasis. Reconstitution with recombinant human MBL before and during the HSV-2 infection dramatically lowered the viral titres in the liver. Taken together, the data show that MBL modulates the response to HSV-2 in mice by affecting neutralization of the virus. To analyse if MBL plays a role in establishment and progression of human HSV-2 infection we analysed MBL levels in the serum samples from asymptomatic (virus-exposed people who have never displayed symptoms of HSV-2 infection) and symptomatic HSV-2 patients (people with recurrent HSV-2 infections). We found that the frequency of the MBL deficiency (<100 ng/ml) was higher in the symptomatic group and significantly different from that in the asymptomatic group (P = 0.0369). This suggests that lack of MBL-mediated complement activation increases susceptibility to viral infection.
Asunto(s)
Herpes Simple/inmunología , Herpesvirus Humano 2/inmunología , Lectina de Unión a Manosa/inmunología , Adulto , Anciano , Alanina Transaminasa/sangre , Animales , Encéfalo/inmunología , Femenino , Herpes Genital/inmunología , Herpes Simple/sangre , Homeostasis/inmunología , Humanos , Hígado/inmunología , Masculino , Lectina de Unión a Manosa/sangre , Ratones , Ratones Noqueados , Persona de Mediana Edad , Proteínas Recombinantes/inmunología , Recurrencia , Bazo/inmunología , Carga Viral/métodos , Proteínas Virales/inmunologíaRESUMEN
OBJECTIVES: This study was conducted to evaluate the long term clinical and electrophysiological outcome by recording the H reflex in a consecutive series of six patients treated by selective tibial neurotomy for spastic equinus foot. METHOD: The amplitudes of Hmax reflexes, Mmax responses, and Hmax:Mmax ratio were recorded in six patients with chronic lower limb spasticity, before and after surgery, at day 1 and 8 months and 24 months after selective tibial neurotomy. The passive range of movement, the stretch reflex score according to the Tardieu scale, the osteoarticular and tendon repercussions, and the quality of motor control of dorsiflexion were evaluated preoperatively and postoperatively. RESULTS: At the end of the study, all patients presented a reduction of equines. Gait and Tardieu's score of spasticity had improved in all patients. Active dorsiflexion of the ankle was unchanged in four patients, but two improved by 5 degrees to 12 degrees. In five cases, fascicular resection of the superior nerve to soleus was, alone, sufficient to reduce spastic equinus foot, without recurrence, for a mean follow up of 28 months. Two patients were reoperated on, one for remaining spasticity related to an underestimated spasticity of the gastrocnemius muscles, and the other for painful claw toes. Hmax, Mmax, and Hmax:Mmax ratios were significantly lower the day after surgery. The reduction of Hmax and Hmax/Mmax ratio remained stable over time and was still statistically significant two years after the operation. However, the value of Mmax eight months postoperatively was no longer significantly different from the preoperative value. CONCLUSION: This study shows the long term efficacy of the selective tibial neurotomy as treatment of spastic equinus foot. Neurotomy confined to fibres supplying the soleus muscle is sufficient in most cases and acts by decreasing sensory afferents without significant long term motor denervation.
Asunto(s)
Pie Equino/cirugía , Reflejo H , Procedimientos Neuroquirúrgicos/métodos , Tibia/inervación , Adolescente , Adulto , Electrofisiología , Femenino , Humanos , Masculino , Neuronas Motoras , Tibia/cirugía , Resultado del TratamientoRESUMEN
OBJECTIVE: This prospective, nonrandomized, noncontrolled study was performed to evaluate the results of a new type of neurotomy, namely the soleus neurotomy, for treatment of the spastic equinus foot. METHODS: Between May 1996 and March 1998, 46 patients were treated for a spastic equinus foot. Clinical status, spasticity (Ashworth Scale score), and kinematic parameters of the gait were determined before and after surgery. The neurotomy was performed on the upper nerve of the soleus in all cases and was associated with other neurotomies (lower nerve of the soleus, 21 patients; gastrocnemius, 9 patients, tibialis posterior, 18 patients; flexor hallucis longus, 16 patients; and flexor digitorum longus, 17 patients). RESULTS: The mean follow-up period was 15 months (range, 8-28 mo). The equinus deformity disappeared clinically in all patients. Before the operation, all patients had an Ashworth Scale score of 2, with an inexhaustible clonus present on knee extension and persisting with knee flexion (Tardieu Scale score, 4), which was abolished in 95% of the patients after surgery. Two patients still had some clonus on knee extension; this did not interfere with their clinical improvement. Knee recurvatum disappeared in eight patients. Analysis of kinematic parameters demonstrated a statistically significant increase in joint motion of the second rocker (P = 0.0026) of the ankle during stance. The duration of the stance or swing phase, length of the walking cycle, and velocity or rate of spontaneous walking were not significantly modified. CONCLUSION: The study demonstrated that soleus neurotomy is effective for the treatment of spastic equinus foot, leading to abolition of spasticity and improvement in the range of ankle motion during the stance phase of gait.
Asunto(s)
Pie Equino/complicaciones , Pie Equino/cirugía , Espasticidad Muscular/complicaciones , Espasticidad Muscular/cirugía , Músculo Esquelético/inervación , Músculo Esquelético/cirugía , Nervios Periféricos/cirugía , Adolescente , Adulto , Anciano , Tobillo/inervación , Tobillo/fisiopatología , Fenómenos Biomecánicos , Niño , Pie Equino/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Espasticidad Muscular/fisiopatología , Músculo Esquelético/fisiopatología , Procedimientos Neuroquirúrgicos/métodos , Estudios Prospectivos , Resultado del Tratamiento , Caminata/fisiologíaRESUMEN
BACKGROUND: Delayed elimination kinetics of steroidal neuromuscular blocking agents have been observed in patients with cirrhosis. Like other steroidal muscle relaxants, rapacuronium may, in part, be eliminated by the liver. To determine the influence of liver disease on its neuromuscular blocking effect, we studied the pharmacokinetics and pharmacodynamics of rapacuronium in patients with cirrhosis. METHODS: Sixteen patients undergoing elective surgery or endoscopy with general anesthesia, eight with cirrhosis and eight with normal liver function, were studied. Anesthesia was induced with fentanyl 2 microg/kg and thiopental 5-7 mg/kg and maintained with 60% nitrous oxide and 0.6-0.8% isoflurane in oxygen and repeated doses of fentanyl 1 microg/kg. Rapacuronium 1.5 mg/kg was administered intravenously before tracheal intubation. Thumb adduction force evoked by supramaximal ulnar nerve stimulation was recorded in 16 patients. Venous blood was sampled at frequent intervals for 8 h. Rapacuronium and its breakdown product Org 9488 were measured in plasma by high-pressure liquid chromatography. Values are reported as median (range). RESULTS: The central volume of distribution was increased to 131 (104-141) ml/kg in patients with cirrhosis (P < 0.01), compared with 75 (47-146) ml/kg in controls. The total apparent volume of distribution was also increased (P < 0.05) to 331 (284-488) ml/kg in patients with cirrhosis, compared with 221 (124-285) ml/kg in controls. The elimination half-life was 88 (77-102) min in controls and 90 (76-117) min in patients with cirrhosis. Plasma clearance was increased (P < 0.05) to 6.9 (6.1-8.9) ml x min(-1) x kg(-1) in patients with cirrhosis, compared with 5.3 (4.2-8.4) ml x min(-1) x kg(-1) in controls. Rapacuronium neuromuscular blocking effect was similar between the two groups. Onset time was 65 (40-110) s in controls and of 60 (52-240) s in patients with cirrhosis. Time to return to 90% of thumb adduction force control value was of 49 (28-80) min in controls and 47 (28-71) min in patients with cirrhosis. CONCLUSION: The neuromuscular blocking effect of a single bolus dose of rapacuronium in patients with cirrhosis is not different from that of patients with normal hepatic function. No decrease in plasma clearance of rapacuronium was observed in patients with cirrhosis.
Asunto(s)
Cirrosis Hepática/metabolismo , Fármacos Neuromusculares no Despolarizantes/farmacología , Fármacos Neuromusculares no Despolarizantes/farmacocinética , Bromuro de Vecuronio/análogos & derivados , Adulto , Anciano , Anestesia General , Cromatografía Líquida de Alta Presión , Estimulación Eléctrica , Femenino , Semivida , Humanos , Cirrosis Hepática/fisiopatología , Pruebas de Función Hepática , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Nervio Cubital/efectos de los fármacos , Bromuro de Vecuronio/farmacocinética , Bromuro de Vecuronio/farmacologíaRESUMEN
BACKGROUND: Paralysis of the vocal cords is one objective of using relaxants to facilitate tracheal intubation. This study compares the neuromuscular blocking effect of succinylcholine and rocuronium on the larynx, the diaphragm, and the adductor pollicis muscle. METHODS: Electromyographic response was used to compare the neuromuscular blocking effect of succinylcholine and rocuronium on the laryngeal adductor muscles, the diaphragm, and the adductor pollicis muscle. Sixteen patients undergoing elective surgery were anesthetized with propofol and fentanyl, and their tracheas were intubated without neuromuscular blocking agents. The recurrent laryngeal and phrenic nerves were stimulated at the neck. The electromyographic response was recorded from electrodes placed on the endotracheal tube and intercostally before and after administration of 1 mg/kg succinylcholine or 0.6 mg/kg rocuronium. RESULTS: The maximum effect was greater at the adductor pollicis (100 and 99%) than at the larynx (96 and 97%) and the diaphragm (94 and 96%) after administration of succinylcholine and rocuronium, respectively (P < or = 0.05). Onset time was not different between the larynx (58+/-10 s), the diaphragm (57+/-8 s), and the adductor pollicis (54+/-13 s), after succinylcholine (all mean +/- SD). After rocuronium, onset time was 124+/-39 s at the larynx, 130+/-44 s at the diaphragm, and 115+/-21 s at the adductor pollicis. After succinylcholine administration, time to 90% recovery was 8.3+/-3.2, 7.2+/-3.5, and 9.1+/-3.0 min at the larynx, the diaphragm, and the adductor pollicis, respectively. Time to 90% recovery after rocuronium administration was 34.9+/-7.6, 30.4+/-4.2, and 49.1+/-11.4 min at the larynx, the diaphragm, and the adductor pollicis, respectively. CONCLUSION: Neuromuscular blocking effect of muscle relaxants on the larynx can be measured noninvasively by electromyography. Although the larynx appears to be resistant to muscle relaxants, we could not demonstrate that its onset time differed from that of peripheral muscles.
Asunto(s)
Androstanoles/farmacología , Diafragma/efectos de los fármacos , Laringe/efectos de los fármacos , Fármacos Neuromusculares Despolarizantes/farmacología , Fármacos Neuromusculares no Despolarizantes/farmacología , Succinilcolina/farmacología , Adulto , Diafragma/fisiología , Electromiografía , Femenino , Humanos , Laringe/fisiología , Masculino , Persona de Mediana Edad , Unión Neuromuscular/efectos de los fármacos , RocuronioRESUMEN
BACKGROUND: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. METHODS: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg.kg-1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg.kg-1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg.kg-1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. RESULTS: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). CONCLUSION: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.
Asunto(s)
Colinesterasas/sangre , Isoquinolinas/farmacología , Fármacos Neuromusculares no Despolarizantes/farmacología , Adulto , Anciano , Atracurio/sangre , Atracurio/farmacología , Estimulación Eléctrica/métodos , Potenciales Evocados Motores/efectos de los fármacos , Femenino , Humanos , Hidrólisis , Isoquinolinas/sangre , Masculino , Persona de Mediana Edad , Mivacurio , Contracción Muscular/efectos de los fármacos , Músculo Esquelético/inervación , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes/sangre , Recuperación de la Función , Pulgar/inervación , Factores de Tiempo , Torniquetes , Bromuro de Vecuronio/sangre , Bromuro de Vecuronio/farmacologíaRESUMEN
Although subjects often report difficulty with swallowing shortly after receiving neuromuscular blocking agents, difficulty with swallowing during recovery from neuromuscular blocking agents appears to be infrequent. We have used electromyography to compare onset and recovery at the diaphragm and geniohyoid airway muscles after an intubating dose of mivacurium (0.2 mg kg-1) to determine if the geniohyoid muscles were particularly sensitive to neuromuscular blocking agents. Twelve adults undergoing elective surgery were anaesthetized with propofol and fentanyl and the trachea intubated without neuromuscular blocking agents. The left hypoglossal and right phrenic nerves were stimulated with percutaneous needle electrodes and the electromyogram recorded with surface electrodes. EMG responses were measured after a bolus dose of mivacurium 0.2 mg kg-1. Recordings were also made of the mechanical response of the adductor pollicis to supramaximal ulnar nerve stimulation. There was no difference in the rate of onset of block for geniohyoid muscles and the diaphragm, but recovery to 25% and 90% of the control response was shorter at the diaphragm (median 14.5 (95% confidence limits 12.9-15.3) min and 23.8 (21.7-26) min) than at the geniohyoid muscle (19.4 (15.6-20.1) min and 29.2 (26.3-31.4) min), respectively (P < 0.05). When the train-of-four ratio of the mechanical response of the thumb reached 70%, the diaphragm and geniohyoid muscles had recovered completely in all patients.
Asunto(s)
Diafragma/efectos de los fármacos , Isoquinolinas/farmacología , Músculo Esquelético/efectos de los fármacos , Fármacos Neuromusculares no Despolarizantes/farmacología , Adulto , Anestesia General , Deglución/efectos de los fármacos , Electromiografía/efectos de los fármacos , Potenciales Evocados/efectos de los fármacos , Humanos , Persona de Mediana Edad , Mivacurio , Unión Neuromuscular/efectos de los fármacos , Factores de TiempoRESUMEN
The duration of clinical relaxation induced by vecuronium and reversal by neostigmine was studied in 40 patients with renal failure (RF) and 40 patients with normal renal function (NL) under general anesthesia. Patients were premedicated with flunitrazepam, and anesthesia commenced with fentanyl 1-2 micrograms/kg, thiopental 5-8 mg/kg, and vecuronium 0.1 mg/kg. Anesthesia was maintained with 60% nitrous oxide in oxygen, isoflurane 0.3%-1.0% end-tidal concentration, and 1 microgram/kg fentanyl every 20-30 min. Neuromuscular block was reversed by the administration of intravenous neostigmine 40 mg/kg at the time of reappearance of either two or four responses to the train-of-four (TOF) stimulation. Monitoring of neuromuscular function consisted of supramaximal TOF stimulation of the ulnar nerve and the evoked thumb response was registered using a force transducer. Spontaneous recovery time, reversal time, and the time to recovery of TOF ratio to 0.7 were recorded. RF did not prolong the vecuronium neuromuscular blocking effect, reversal was achieved at the same rate in NL as in RF, and the duration of reversal of neuromuscular blocking effect of vecuronium was not influenced by the time of administration of neostigmine. Therefore, the neuromuscular blocking effect of a tracheal intubating dose of vecuronium can be reversed at the same rate in patients with end-stage RF as in patients with normal kidney function.
Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Neostigmina/farmacología , Fármacos Neuromusculares no Despolarizantes/antagonistas & inhibidores , Insuficiencia Renal/fisiopatología , Bromuro de Vecuronio/antagonistas & inhibidores , Adulto , Anciano , Anestesia General , Interacciones Farmacológicas , Humanos , Riñón/fisiología , Persona de Mediana EdadRESUMEN
In a controlled, randomized study, we evaluated duration of neuromuscular block in 80 patients undergoing routine abdominal surgery. Forty patients were aged 18-50 yr (control group) and 40 patients were more than 65 yr (elderly group). All patients had normal plasma creatinine concentrations. After induction of anaesthesia, patients were allocated randomly to receive either atracurium 0.5 mg kg-1 or vecuronium 0.1 mg kg-1 to facilitate tracheal intubation. Monitoring of the evoked response of the adductor pollicis muscle to supramaximal single twitch ulnar nerve stimulation every 10 s was performed and measured with a strain gauge. Repeat doses of atracurium 0.1 mg kg-1 or vecuronium 0.02 mg kg-1 were administered when the adductor pollicis response recovered to 25% of the control twitch height. We found that the duration of action of the initial dose of atracurium was similar in the control and elderly groups, and it did not vary after repeated doses. However, the initial dose of vecuronium caused a significantly longer period of clinical block in the elderly group compared with the controls, and the duration of action of repeated doses was longer in the elderly group. We conclude that as there is a risk of prolonged effect of vecuronium in the elderly, monitoring of neuromuscular function is recommended in this group. Alternatively, atracurium should be preferred for prolonged surgery in elderly patients.
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Anestesia General , Atracurio , Bromuro de Vecuronio , Abdomen/cirugía , Adolescente , Adulto , Factores de Edad , Anciano , Potenciales Evocados , Humanos , Persona de Mediana Edad , Unión Neuromuscular/efectos de los fármacos , Unión Neuromuscular/fisiología , Factores de TiempoRESUMEN
BACKGROUND: Residual paralysis of suprahyoid muscles may occur when the adductor pollicis response has completely recovered after the administration of a neuromuscular blocking agent. The response of the geniohyoid muscle to intubating doses of muscle relaxants is evaluated and compared to that of adductor pollicis. METHODS: Sixteen patients undergoing elective surgery under general anesthesia were given 5-7 mg.kg-1 thiopental and 2 micrograms.kg-1 fentanyl intravenously for induction of anesthesia. Eight (half) patients then received 0.5 mg.kg-1 atracurium, and the other eight received 0.1 mg.kg-1 vecuronium. The evoked response (twitch height, TH) of the adductor pollicis was monitored by measuring the integrated electromyographic response (AP EMG) on one limb and the mechanical response, using a force transducer (AP force), on the other. The activity of geniohyoid muscle (GH EMG) was measured using submental percutaneous electrodes. The following variables were measured: maximal TH depression; onset time for neuromuscular blockade to 50%, 90%, and maximal TH depression (OT50, OT90, and OTmax); times between administration of neuromuscular blocking agent and TH recovery to 10%, 25%, 50%, 75%, and 90% of control; and time for return of train-of-four ratio to return to 0.7. RESULTS: The principal findings were (1) OTmax was significantly (P < 0.01) shorter for geniohyoid than for adductor pollicis after either atracurium or vecuronium (OTmax was 216, 256, and 175 s for AP force, AP EMG, and GH EMG, with atracurium and 181, 199, and 144 s with vecuronium, respectively), and (2) the evoked EMG of geniohyoid recovered at the same speed as the EMG of adductor pollicis after an intubating dose of atracurium or vecuronium (recovery of TH to 75% of control at 50, 48, 42 min with AP force, AP EMG, and GH EMG with atracurium and 46, 45, and 42 min with vecuronium, respectively). CONCLUSIONS: Once the adductor pollicis response has returned to normal values after a single intubating dose of atracurium or vecuronium, the risk of residual depression of the TH of the geniohyoid muscle, one of the principal muscles contributing to airway patency, appears unlikely.
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Atracurio/farmacología , Músculos/efectos de los fármacos , Bromuro de Vecuronio/farmacología , Adulto , Potenciales Evocados , Humanos , Persona de Mediana Edad , Sistema Respiratorio/efectos de los fármacos , PulgarRESUMEN
This is a report on a case of severe intraoperative anaphylactic shock, developing within several hours of percutaneous puncture of a liver hydatid cyst, performed under echographic control, necessitating recovery from the shock state and discontinuation of the operative intervention. Inferences are reached regarding the most adequate treatment tactics to be adopted in handling such cases. Percutaneous puncture is discarded as a therapeutic approach because of the great risk of anaphylaxis with eventual lethal outcome, and the likelihood of severe abdominal echinococcosis development at a later period.
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Anafilaxia/etiología , Biopsia con Aguja/efectos adversos , Equinococosis Hepática/complicaciones , Complicaciones Intraoperatorias/etiología , Enfermedad Aguda , Anciano , Equinococosis Hepática/diagnóstico , Equinococosis Hepática/cirugía , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Ultrasonografía IntervencionalAsunto(s)
Envejecimiento/fisiología , Isoquinolinas/farmacología , Fármacos Neuromusculares no Despolarizantes/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Anestesia General , Anestesia por Inhalación , Anestesia Intravenosa , Procedimientos Quirúrgicos Electivos , Humanos , Isoquinolinas/administración & dosificación , Persona de Mediana Edad , Mivacurio , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Factores de Tiempo , Nervio Cubital/efectos de los fármacosRESUMEN
BACKGROUND: Rocuronium, like other steroidal nondepolarizing muscle relaxants, may in part be eliminated by the liver. To determine the influence of liver disease on its neuromuscular blocking effect, we studied the pharmacokinetics and pharmacodynamics of rocuronium in patients with cirrhosis. METHODS: Eighteen patients undergoing elective surgery, 10 with cirrhosis and 8 with normal liver function, were studied. Anesthesia was induced with intravenous thiopental 5-7 mg.kg-1 and maintained with 60% nitrous oxide in oxygen and repeated doses of fentanyl 2 micrograms.kg-1. The force of thumb adduction in response to supramaximal ulnar nerve stimulation was monitored and recorded. An intravenous bolus of rocuronium 0.6 mg.kg-1 was administered and venous blood sampled at frequent intervals for 6 h. Plasma concentrations of rocuronium was measured by high-pressure liquid chromatography. Data were fitted to both a pharmacokinetic and a pharmacodynamic model by using a two-compartment open model and an effect compartment model. Data were analyzed by least-squares regression. RESULTS: The onset of neuromuscular blockade was longer (P < 0.01) in patients with cirrhosis (158 +/- 56 s) than in normal patients (108 +/- 33 s). Recovery of the thumb twitch to 75 and 90% of its control value was 77 +/- 25 and 88 +/- 29 min in cirrhotic patients versus 57 +/- 11 and 64 +/- 13 min, respectively, in normal patients (P < 0.05). The central volume of distribution of rocuronium was 104 +/- 21 in cirrhotic patients and 78 +/- 24 ml.kg-1 in normal patients (P < 0.05). No significant difference in elimination kinetics was observed between the two groups. The elimination half-life was 87.5 +/- 17.5 min in normal patients and 96.0 +/- 36.8 min in cirrhotic patients (difference not significant). This increased onset time was linearly correlated to the increased central volume of distribution of rocuronium in cirrhosis. CONCLUSION: Rocuronium onset time is longer in cirrhotic patients than in those with normal liver function; this can be explained by an increase in the volume in which rocuronium initially distributes. Although elimination kinetics are unchanged in patients with cirrhosis, rocuronium recovery time is prolonged in cirrhotic patients.