RESUMEN
STUDY OBJECTIVE: To compare the influence of anesthetic depth and choice of volatile anesthetic drug on the incidence and severity of airway hyperreactivity associated with Laryngeal Mask Airway (LMA) removal. DESIGN: Randomized observer-blinded study. SETTING: Ambulatory Surgical Center at a University Medical Center. PATIENTS: 123 ASA physical status I and II children undergoing infraumbilical procedures. INTERVENTIONS: Patients were randomly assigned to one of four treatment groups: Group 1 = anesthetic induction with halothane, maintenance with isoflurane, nitrous oxide (N(2)O), and oxygen (O(2)), LMA removed when child awakened; Group 2 =anesthetic induction and maintenance as in Group 1, LMA removed while child anesthetized with age adjusted 2 minimum alveolar concentration (MAC) end-tidal concentration of isoflurane; Group 3 = anesthetic induction and maintenance with sevoflurane, N(2)O, and O(2), LMA removed when child awakened; Group 4 = anesthetic induction and maintenance as in Group 3, but LMA removed while child anesthetized with age-adjusted 2 MAC end-tidal concentration of sevoflurane. MEASUREMENTS AND MAIN RESULTS: Severity of airway hyperreactivity was graded as mild, moderate, or severe. A significant difference was not found amongst the four groups with respect to mild and moderate airway hyperreactivity. Severe airway hyperreactivity leading to a critical event [partial or complete laryngospasm with oxygen saturation (SPO(2)) < 85%] was only encountered in Group 1 patients (incidence 13%). Adverse airway events (SPO(2) < 90%, vomiting and bronchospasm) were also significantly higher in Group 1 (p < 0.05). Isoflurane use was independently associated with significantly higher airway hyperreactivity when compared with sevoflurane (p < 0.05). CONCLUSIONS: Depth of anesthesia during LMA removal does not appear to affect the incidence or severity of airway hyperreactivity when sevoflurane is the maintenance anesthetic. However, awake LMA removal during isoflurane anesthesia results in a higher incidence of adverse airway events and carries the risk of severe airway hyperreactivity.
Asunto(s)
Anestesia , Anestésicos por Inhalación/administración & dosificación , Espasmo Bronquial/etiología , Máscaras Laríngeas/efectos adversos , Laringismo/etiología , Preescolar , Humanos , Lactante , Infecciones del Sistema Respiratorio/etiologíaRESUMEN
UNLABELLED: Reports of transient neurological symptoms with the use of subarachnoid lidocaine has generated interest in alternate local anesthetics of intermediate duration, such as mepivacaine. This prospective randomized, double-blinded, dose-response study examined the anesthetic and recovery profiles of 60- and 80-mg doses of preservative-free plain mepivacaine for ambulatory spinal anesthesia. Sixty patients undergoing ambulatory anterior cruciate ligament repair of the knee under spinal anesthesia were randomized into two groups; Group 1 (29 patients) received 4 mL of 1.5% (60-mg dose) and Group 2 (31 patients) received 4 mL of 2% (80-mg dose) of plain mepivacaine. All patients received a combined spinal-epidural anesthetic technique. The epidural catheter was used only in the event the surgery outlasted the duration of surgical anesthesia with subarachnoid mepivacaine. Epidural supplementation was administered in three patients (12%) in Group 1 and one patient (3%) in Group 2 when the sensory block regressed to L-1 with surgery expected to last longer than 15 min. The cephalad dermatome level of the block and degree of motor block was comparable in the two groups. Times to two-segment and T-10 regression were comparable in the two groups (112 +/- 26 min in Group 1 versus 122 +/- 28 min in Group 2). Time to L-1 regression was significantly longer in Group 2 (146 +/- 28 min in Group 1 versus 159 +/- 19 min in Group 2). All of the ambulatory milestones were significantly faster in Group 1. Side effects, such as hypotension and emesis were negligible, severe bradycardia and urinary retention did not occur, and none of the patients in the two groups reported transient neurological symptoms over 24 h. In conclusion, plain mepivacaine in a 60- or 80-mg dose is a suitable local anesthetic choice for ambulatory spinal anesthesia with respect to anesthetic, as well as recovery profiles. IMPLICATIONS: We evaluated the anesthetic and recovery profiles of 60- and 80-mg doses of plain mepivacaine for ambulatory spinal anesthesia. Both doses produced comparable sensory and motor block. Sensory and motor regression and ambulatory milestones were 20-30 min longer with the 80-mg dose. Side effects were negligible and transient neurological symptoms were not reported during a 24-h follow-up.
Asunto(s)
Periodo de Recuperación de la Anestesia , Anestesia Raquidea , Anestésicos Locales/administración & dosificación , Mepivacaína/administración & dosificación , Adolescente , Adulto , Procedimientos Quirúrgicos Ambulatorios , Ligamento Cruzado Anterior/cirugía , Método Doble Ciego , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/epidemiología , Estudios ProspectivosRESUMEN
UNLABELLED: Because succinylcholine has obvious advantages for facilitating endotracheal intubation in the ambulatory setting (e.g., low cost, fast onset, and no need for reversal of neuromuscular block), it is important to determine whether this muscle relaxant is indeed associated with an increased incidence of postoperative myalgias, compared with alternative but more expensive nondepolarizing muscle relaxants. We studied 119 outpatients undergoing endoscopic nasal sinus surgery or septoplasty. The anesthetic technique consisted of propofol/lidocaine for induction, followed by isoflurane/nitrous oxide/oxygen for maintenance. Oral tracheal intubation was performed by using a fiberscope. Patients were randomly assigned to one of two muscle relaxant groups. Group 1 patients received d-tubocurarine 3 mg followed by succinylcholine 1.5 mg/kg. Group 2 patients received mivacurium 0.2 mg/kg. After recovery from anesthesia, patients were asked whether they had any muscle pain and/or stiffness. Pain was categorized by location and quantified by using a verbal scale (from 0 to 10). Analgesic usage and myalgias limiting ambulation were recorded. After discharge from the ambulatory surgery unit, patients were contacted by telephone on Postoperative Day 1. If patients complained of myalgias, they were contacted by telephone on Days 2 and 3. Only one patient (in the mivacurium-treated group) reported myalgia as a limiting factor in ambulation or resumption of normal activity. There were no differences between groups with respect to the incidence (21% in the succinylcholine-treated group and 18% in the mivacurium-treated group), location, or severity of myalgia. In conclusion, succinylcholine (preceded by pretreatment with d-tubocurarine and lidocaine) is not associated with an increased incidence of myalgias, compared with mivacurium, when used to facilitate tracheal intubation in patients undergoing ambulatory nasal surgery. IMPLICATIONS: The results of this study show that the frequency of muscle pains after surgery in outpatients is approximately 20%, regardless of whether succinylcholine (after precurarization) or mivacurium is used to assist in insertion of the breathing tube.
Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Anestésicos Locales/administración & dosificación , Lidocaína/administración & dosificación , Enfermedades Musculares/inducido químicamente , Fármacos Neuromusculares Despolarizantes , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Dolor Postoperatorio/inducido químicamente , Succinilcolina , Tubocurarina/administración & dosificación , Adulto , Periodo de Recuperación de la Anestesia , Contraindicaciones , Femenino , Humanos , Intubación Intratraqueal , Isoquinolinas/administración & dosificación , Masculino , Mivacurio , Enfermedades Musculares/tratamiento farmacológico , Fármacos Neuromusculares Despolarizantes/administración & dosificación , Fármacos Neuromusculares Despolarizantes/efectos adversos , Dolor Postoperatorio/tratamiento farmacológico , Senos Paranasales/cirugía , Succinilcolina/administración & dosificación , Succinilcolina/efectos adversos , Encuestas y CuestionariosRESUMEN
UNLABELLED: We compared sedation quality, intraocular pressure (IOP) changes, and recovery profiles in patients who received propofol or propofol-ketamine sedation during placement of the retrobulbar nerve block (RBB). Seventy elderly patients undergoing cataract extraction according to a prospective, randomized, double-blinded protocol were preoperatively evaluated with a Mini-Mental State examination and baseline IOP. A hypnotic dose was provided with either propofol (Group P) or a propofol-ketamine (Group PK) combination. The IOP measurement was repeated, and the surgeon initiated the RBB. Supplemental study drug was given if needed. The level of sedation was considered acceptable if the patient exhibited minimal or no movement and grimacing with needle insertion. Patients were evaluated in terms of quality of sedation, cardiopulmonary stability, and recovery profile. Compared with patients in Group P, patients in Group PK had a significantly faster onset of acceptable sedation (Group P 235 +/- 137 s versus Group PK 164 +/- 67 s) and required significantly less supplemental sedation (Group P 1.1 +/- 1.9 mL versus Group PK 0.15 +/- 0.3 mL). Additionally, none of the Group PK patients required ventilatory assistance, but two patients in Group P required assisted mask ventilation. In conclusion, the addition of ketamine (13.2 +/- 3.3 mg) to propofol (44 +/- 11 mg) decreased the hypnotic requirement and improved the quality of sedation without prolonging recovery. IMPLICATIONS: Anesthesiologists frequently perform retrobulbar blocks while simultaneously providing sedation. Using ketamine to supplement propofol sedation provided a faster onset and improved the quality of sedation during the retrobulbar block procedure.
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Analgésicos , Periodo de Recuperación de la Anestesia , Sedación Consciente , Hipnóticos y Sedantes , Presión Intraocular/efectos de los fármacos , Ketamina , Bloqueo Nervioso , Propofol , Anciano , Procedimientos Quirúrgicos Ambulatorios , Analgésicos/administración & dosificación , Extracción de Catarata , Cognición , Método Doble Ciego , Ojo , Humanos , Hipnóticos y Sedantes/administración & dosificación , Ketamina/administración & dosificación , Satisfacción del Paciente , Medicación Preanestésica , Propofol/administración & dosificación , Estudios ProspectivosRESUMEN
UNLABELLED: In this prospective, randomized, double-blind, placebo-controlled study, we examined the effect of preoperative dexamethasone on postoperative nausea and vomiting (PONV) and 24-h recovery in children undergoing tonsillectomy. One hundred thirty children, 2-12 yr of age, ASA physical status I or II, completed the study. All children received oral midazolam 0.5-0.6 mg/kg preoperatively. Anesthesia was induced with halothane and nitrous oxide in 60% oxygen and maintained with nitrous oxide and isoflurane. Intubation was facilitated by mivacurium 0.2 mg/kg. Each child received fentanyl 1 microgram/kg i.v. before initiation of surgery, as well as dexamethasone 1 mg/kg (maximal dose 25 mg) (steroid group) or an equal volume of saline (control group). Intraoperative fluids were standardized to 25-30 mL/kg lactated Ringer's solution. All tonsillectomies were performed under the supervision of one attending surgeon using an electrodissection technique. Postoperatively, fentanyl and acetaminophen with codeine elixir were administered as needed for pain. Rescue antiemetics were administered when a child experienced two episodes of retching and/or vomiting. Before home discharge, the incidence of PONV, need for rescue antiemetics, quality or oral intake, and analgesic requirements did not differ between groups. However, during the 24 h after discharge, more patients in the control group experienced PONV (62% vs 24% in the steroid group) and complained of poor oral intake. Additionally, more children in the control group (8% vs 0% in the steroid group) returned to the hospital for the management of PONV and/or poor oral intake. The preoperative administration of dexamethasone significantly decreased the incidence of PONV over the 24 h after home discharge in these children. IMPLICATIONS: In this double blind, placebo-controlled study, we examined the efficacy of a single large dose (1 mg/kg; maximal dose 25 mg) of preoperative dexamethasone on posttonsillectomy postoperative nausea and vomiting (PONV) in children 2-12 yr of age undergoing tonsillectomy. Compared with placebo, dexamethasone significantly decreased the incidence of PONV in the 24 h after discharge, improved oral intake, decreased the frequency of parental phone calls, and resulted in no hospital returns for the management of PONV and/or poor oral intake.
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Adenoidectomía/efectos adversos , Antieméticos/uso terapéutico , Dexametasona/uso terapéutico , Náusea/prevención & control , Complicaciones Posoperatorias/prevención & control , Tonsilectomía/efectos adversos , Vómitos/prevención & control , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Humanos , Inyecciones Intravenosas , Placebos , Cuidados Preoperatorios , Estudios ProspectivosRESUMEN
This prospective, randomized double-blind study was conducted to examine the effect of intraoperative opioid (fentanyl) supplementation on postoperative analgesia, emesis, and recovery in ambulatory patients receiving propofol-nitrous oxide anesthesia. Eighty patients undergoing ambulatory gynecologic laparoscopy participated. Confounding variables that could influence the incidence of postoperative emesis were controlled. Patients received either fentanyl 100 micrograms (Group I) or ketorolac 60 mg (Group II) intravenously (IV) at the time of anesthetic induction. No further analgesic supplements were given intraoperatively. Anesthesia was induced with propofol and maintained with propofol-nitrous oxide. Atracurium was used for muscle relaxation and reversed with neostigmine and glycopyrrolate. Postoperative pain during early recovery was treated with IV fentanyl 25-50 micrograms (Group I) or IV ketorolac 15-30 mg (Group II). Subsequent breakthrough pain in both groups was treated with IV fentanyl 25 micrograms increments as needed (rescue analgesia). Eighty-four percent of patients in Group I required analgesics during early recovery versus 56% of patients in Group II (P < 0.05). Maintenance dose of propofol was significantly lower in Group I (129 +/- 35 micrograms.kg-1.min-1 than in Group II (170 +/- 63 micrograms.kg-1.min-1. Immediate recovery (emergence) in the two groups was comparable, despite different propofol requirements. Although the incidence of emetic sequelae in the postanesthesia care unit was not significantly different between the two treatment groups, a significantly larger number of patients in Group I (fentanyl group) had emetic sequelae that required therapeutic intervention (Group I 29% versus Group II 10%). Patients in Group I also took a significantly longer time to ambulate and meet criteria for home discharge. These results indicate that, in patients undergoing ambulatory gynecologic laparoscopy, the practice of administering a small dose of fentanyl at the time of anesthetic induction reduces maintenance propofol requirement, but fails to provide effective postoperative analgesia. Fentanyl administration at anesthetic induction increased the need for rescue antiemetics. The relative severity of emetic sequelae could have contributed to delay in ambulation and discharge.
Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Analgésicos Opioides/uso terapéutico , Periodo de Recuperación de la Anestesia , Anestésicos Intravenosos/administración & dosificación , Fentanilo/uso terapéutico , Genitales Femeninos/cirugía , Cuidados Intraoperatorios , Laparoscopía , Propofol/administración & dosificación , Adulto , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/administración & dosificación , Antieméticos/administración & dosificación , Antieméticos/uso terapéutico , Factores de Confusión Epidemiológicos , Método Doble Ciego , Femenino , Fentanilo/administración & dosificación , Humanos , Inyecciones Intravenosas , Ketorolaco , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Alta del Paciente , Cuidados Posoperatorios , Estudios Prospectivos , Tolmetina/administración & dosificación , Tolmetina/análogos & derivados , Tolmetina/uso terapéutico , Vómitos/tratamiento farmacológico , Vómitos/prevención & control , Vigilia/efectos de los fármacos , CaminataRESUMEN
O objetivo deste estudo foi provar que mudando o fluxo de gases fescos em ventiladores, alteraria o Vt (volume corrente) liberado para o paciente. Quatro ventiladores foram selecionados: Narco Air Shields, 702 Frazer Harlake, Dreger A-V e Ohio 7.000. Os volumes gerados pelos quatro ventiladores foram medidos, enquanto trocas no fluxo de gases frescos estavam sendo feitas simultaneamente. Os fluxos de gases frescos foram inicialmente fixados em 10 L. min-1 e a cada 15 minutos foram diminuídos em 1 L. Medidas de Vc (volume corrente) e V (volume minuto) foram feitas e os autores concluíram que os ventiladores estudados falharam em liberar o Vt indicado, quando os FGF foram trocados. A necessidade de um expirômetro foi observada como sendo uma maneira precisa de verificar o exato volume corrente liberado para o paciente anestesiado, tendo a respiraçäo mecanicamente controlada