RESUMO
BACKGROUND: After cardiac surgery, a patient's trachea is usually extubated; however, 2 to 13% of cardiac surgery patients require reintubation in the ICU. OBJECTIVE: The objective of this study was to compare the initial intubation in the cardiac operating room with reintubation (if required) in the ICU following cardiac surgery. DESIGN: A prospective, observational study. SETTING: Department of Anesthesiology and Intensive Care Medicine, Clinical Hospital of Santiago, Spain. PATIENTS: With approval of the local ethics committee, over a 44-month period, we prospectively enrolled all cardiac surgical patients who were intubated in the operating room using direct laryngoscopy, and who required reintubation later in the ICU. MAIN OUTCOME MEASURES: The primary endpoint was to compare first-time success rates for intubation in the operating room and ICU. Secondary endpoints were to compare the technical difficulties of intubation (modified Cormack-Lehane glottic view, operator-reported difficulty of intubation, need for support devices for direct laryngoscopy) and the incidence of complications. RESULTS: A total of 122 cardiac surgical patients required reintubation in the ICU. Reintubation was associated with a lower first-time success rate than in the operating room (88.5 vs. 97.6%, Pâ=â0.0048). Reintubation in the ICU was associated with a higher incidence of Cormack-Lehane grades IIb, III or IV views (34.5 vs. 10.7%, Pâ<â0.0001), a higher incidence of moderate or difficult intubation (17.2 vs. 6.5%, Pâ=â0.0001) and a greater need for additional support during direct laryngoscopy (20.5 vs. 10.7%, Pâ=â0.005). Complications were more common during reintubations in the ICU (39.3 vs. 5.7%, Pâ<â0.0001). CONCLUSION: Compared with intubations in the operating room, reintubation of cardiac surgical patients in the ICU was associated with more technical difficulties and a higher incidence of complications. CLINICAL TRIAL NUMBER: Ethics committee of Galicia number 2015-012.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Unidades de Terapia Intensiva/estatística & dados numéricos , Intubação Intratraqueal/efeitos adversos , Laringoscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Reoperação/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Extubação/estatística & dados numéricos , Feminino , Humanos , Incidência , Intubação Intratraqueal/métodos , Intubação Intratraqueal/estatística & dados numéricos , Laringoscopia/métodos , Laringoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Salas Cirúrgicas/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Reoperação/estatística & dados numéricosRESUMO
In patients with aggressive tumors resistant to conventional pain treatment, regional anaesthesia frequently becomes an alternative therapy. Cervical paravertebral nerve block among several access options to the brachial plexus is barely ever used. We present a case with severe shoulder and upper extremity pain owing to an expanding Pancoast tumor exhibiting compression upon the brachial plexus. Continuous intrathecal morphine infusion and adjuvant treatment was not sufficient to render the patient pain-free. With the addition of paravertebral nerve blockade the patient's pain improved substantially, however without impacting his longevity.
Assuntos
Morfina/uso terapêutico , Bloqueio Nervoso/métodos , Síndromes de Compressão Nervosa , Dor/tratamento farmacológico , Síndrome de Pancoast/complicações , Adulto , Analgésicos Opioides/uso terapêutico , Plexo Braquial/patologia , Cateteres de Demora , Vértebras Cervicais , Humanos , Masculino , Síndromes de Compressão Nervosa/etiologia , Síndromes de Compressão Nervosa/fisiopatologia , Síndromes de Compressão Nervosa/terapiaRESUMO
BACKGROUND: This investigation was designed to compare a new methodology of automated regular bolus with a continuous infusion of local anesthetic for continuous popliteal sciatic block; both regimens were combined with patient-controlled analgesia (PCA). METHODS: Fifty patients undergoing hallux valgus repair were randomly allocated to receive an infusion of 0.125% levobupivacaine administered through a popliteal catheter as an automated regular bolus (n = 25) or as a continuous infusion (n = 25), both combined with PCA. Postoperative pain scores, incremental doses delivered by the PCA, local anesthetic consumed per hour, and the need for rescue tramadol analgesia were recorded. RESULTS: Both dosing regimens provided similar postoperative analgesia. Consumption of local anesthetic (5.14 ml/h, 5-5.75 ml/h) and dose request from the PCA (1, 0-5.4) was lower in the automated bolus group as compared to the continuous infusion group (5.9 ml/h, 5.05-7.8 ml/h; doses by PCA: 6.5, 0-20.5; P < 0.05). The need for rescue tramadol was similar in the two groups. CONCLUSION: In continuous popliteal sciatic block, local anesthetic administered as an automated regular bolus in conjunction with PCA provided similar pain relief as a continuous infusion technique combined with PCA; however, the new dosing regimen reduced the need for additional PCA and the overall consumption of local anesthetic.
Assuntos
Analgesia Controlada pelo Paciente/métodos , Bombas de Infusão , Dor Pós-Operatória/prevenção & controle , Nervo Isquiático/efeitos dos fármacos , Adulto , Idoso , Analgesia Controlada pelo Paciente/instrumentação , Anestésicos Locais/administração & dosagem , Cateteres de Demora , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Medição da Dor/instrumentação , Medição da Dor/métodos , Dor Pós-Operatória/fisiopatologia , Nervo Fibular/efeitos dos fármacos , Nervo Fibular/fisiologia , Estudos Prospectivos , Nervo Isquiático/fisiologiaRESUMO
One of the advantages of lower extremity peripheral nerve blocks compared with neuroaxial Neuraxial techniques is the lack of effect on urinary function. We report two cases of urinary incontinence during continuous sciatic nerve block with stimulating catheters placed using the posterior gluteal Labat approach. The two patients were able to control micturition 6 h after the catheter was removed.
Assuntos
Bloqueio Nervoso , Nervo Isquiático , Incontinência Urinária/induzido quimicamente , Idoso , Procedimentos Cirúrgicos Ambulatórios , Cateterismo , Feminino , Hallux Valgus/cirurgia , Humanos , Pessoa de Meia-Idade , Monitorização Intraoperatória , Micção/fisiologiaRESUMO
BACKGROUND: We designed the present, prospective, randomized, double-blind study to compare the administration of an automated intermittent bolus dose with a conventional technique of continuous infusion of local anesthetic for postoperative analgesia in continuous popliteal sciatic nerve blockade. METHODS: Forty-four patients undergoing hallux valgus repair were randomly assigned to receive either a continuous infusion of 0.125% levobupivacaine with an infusion rate of 5 mL/h (continuous infusion group, n=22) or automated bolus doses of 5 mL every hour of the same local anesthetic (automated bolus group, n=22) for 24 h. Postoperative pain scores were assessed using a verbal rating pain score. The amount of rescue tramadol medication for pain was also recorded. RESULTS: In patients of the automated bolus group there was a reduction in pain scores (P<0.05) during the postoperative period, when compared to patients of the continuous infusion group. Five patients in the automated bolus group (24%) and 11 patients of the continuous group (52%) required rescue tramadol analgesia (P=0.055). CONCLUSION: The present investigation demonstrated that local anesthetic administered by an automated bolus technique provided better postoperative pain relief than a continuous infusion technique for continuous popliteal nerve block after foot surgery.
Assuntos
Anestésicos Locais/administração & dosagem , Bloqueio Nervoso/métodos , Nervo Isquiático , Bupivacaína/administração & dosagem , Bupivacaína/análogos & derivados , Método Duplo-Cego , Feminino , Hallux Valgus/cirurgia , Humanos , Bombas de Infusão , Infusões Intravenosas , Levobupivacaína , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/prevenção & controleRESUMO
BACKGROUND: Various factors markedly affect the onset time and success rate, of peripheral nerve blockade. This prospective, randomized, double-blind study, compared a dose of mepivacaine 300 mg, in a 20 or 30 mL injection volume for sciatic nerve blockade using Labat's posterior approach. METHODS: A total of 90 patients undergoing foot surgery were randomly allocated to receive sciatic nerve block with 20 mL of 1.5% mepivacaine (n = 45) or 30 mL of 1% mepivacaine (n = 45). All blocks were performed with the use of a nerve stimulator (stimulation frequency 2 Hz; intensity 1.5-0.5 mA). In the two groups, appropriate nerve stimulation was elicited at <0.5 mA and the targeted evoked motor response was plantar flexion of the foot. Time required for onset of sensory and motor block in the distribution of the tibial and common peroneal nerves were recorded. A successful block was defined as a complete loss of pinprick sensation in the sciatic nerve distribution with concomitant inability to perform plantar or dorsal flexion of the foot. RESULTS: A greater success rate was observed with 20 mL of 1.5% mepivacaine (96.6%) than with 30 mL of 1% mepivacaine (68.9%; P < 0.05). Time to onset of complete sensory and motor block was shorter after injection of 20 mL of 1.5% mepivacaine (11 +/- 6 min and 13 +/- 7 min, respectively) than after 30 mL of 1% mepivacaine (17 +/- 8 min and 19 +/- 8 min, respectively, P < 0.05). CONCLUSION: In Labat's sciatic nerve blockade, administering a low volume and a high concentration of local anesthetic (1.5% mepivacaine) is associated with a higher success rate and a shorter onset time than a high volume and a low concentration of solution (1% mepivacaine).
Assuntos
Anestésicos Locais/administração & dosagem , Mepivacaína/administração & dosagem , Bloqueio Nervoso/métodos , Nervo Isquiático , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
In this prospective, blinded study, we randomized 56 patients undergoing hallux valgus repair to receive continuous sciatic nerve block using a subgluteal (n = 28) or a posterior popliteal approach (n = 28) with a perineural stimulating catheter. Postoperatively, the stimulating catheter was connected to a patient-controlled analgesia pump with 0.0625% levobupivacaine (basal infusion rate of 3 mL/h, patient-controlled bolus dose of 3 mL, and lockout time of 20 min). Both approaches provided similar postoperative analgesia; however, local anesthetic consumption was larger in the popliteal group (4.9 +/- 1.4 mL/h) compared with the subgluteal group (3.8 +/- 1.1 mL/h; P < 0.05). We conclude continuous postoperative analgesia using stimulating catheters was effective at both injection sites; however, a subgluteal approach reduced the overall amount of local anesthetic.
Assuntos
Cateterismo/métodos , Bloqueio Nervoso/métodos , Nervo Isquiático , Analgesia Controlada pelo Paciente , Anestésicos Locais , Bupivacaína/análogos & derivados , Método Duplo-Cego , Estimulação Elétrica , Hallux Varus , Humanos , Levobupivacaína , Medição da Dor , Dor Pós-OperatóriaRESUMO
For sciatic nerve blockade, no study has defined the optimal volume of local anesthetic required to block the nerve. The current, prospective, randomized investigation was designed to find a minimum volume of 1.5% mepivacaine required to block the sciatic nerve using the subgluteal and posterior popliteal approaches. A total of 56 patients undergoing foot surgery were randomly assigned to receive sciatic nerve block by means of a posterior subgluteal (group subgluteal, n = 28) or a posterior popliteal (group popliteal, n = 28) approaches. All blocks were performed with the use a nerve stimulator (stimulating frequency, 2 Hz, intensity 1.5-0.5 mA) and a perineural stimulating catheter. In all patients, plantar flexion of the foot was elicited at <0.5 mA, to maintain consistency among groups. The volume of local anesthetic used in each patient was based on the modified Dixon's up-and-down method. Complete anesthesia was defined as complete loss of pinprick sensation in the sciatic nerve distribution with concomitant inability to perform plantar or dorsal flexion of the foot 20 min after injection. The mean volume of local anesthetic required to block the sciatic nerve was 12 +/- 3 mL in the subgluteal group and 20 +/- 3 mL in the popliteal group (P < 0.05). The ED95 for adequate block of the sciatic nerve was 17 mL in the subgluteal group and 30 mL in the popliteal group. The authors conclude that a larger volume of local anesthetic is necessary to block the sciatic nerve at a more distal site (popliteal approach) as compared with a more proximal level (subgluteal approach).
Assuntos
Anestésicos Locais/administração & dosagem , Mepivacaína/administração & dosagem , Bloqueio Nervoso/métodos , Feminino , Pé/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do PacienteAssuntos
Betacoronavirus , Infecções por Coronavirus/terapia , Pandemias , Posicionamento do Paciente , Pneumonia Viral/terapia , Decúbito Ventral , Síndrome do Desconforto Respiratório/terapia , Idoso , Anticoagulantes/uso terapêutico , Antivirais/uso terapêutico , Biomarcadores , COVID-19 , Terapia Combinada , Infecções por Coronavirus/sangue , Infecções por Coronavirus/complicações , Infecções por Coronavirus/tratamento farmacológico , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Oxigenoterapia , Pressão Parcial , Pneumonia Viral/sangue , Pneumonia Viral/complicações , Estudos Prospectivos , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/etiologia , SARS-CoV-2 , Vigília , Tratamento Farmacológico da COVID-19Assuntos
Corticosteroides/administração & dosagem , Infecções por Coronavirus/tratamento farmacológico , Inflamação/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Corticosteroides/farmacologia , Idoso , COVID-19 , Infecções por Coronavirus/fisiopatologia , Feminino , Humanos , Inflamação/virologia , Pandemias , Pneumonia Viral/fisiopatologia , Síndrome do Desconforto Respiratório/virologia , Tratamento Farmacológico da COVID-19RESUMO
BACKGROUND AND OBJECTIVES: Ropivacaine and mepivacaine are commonly used local anesthetics for peripheral nerve blockade. The purpose of the present study was to compare onset time, quality of anesthesia, and duration of analgesia with ropivacaine 0.75% and mepivacaine 1.5% for lateral popliteal nerve block. METHODS: Fifty American Society of Anesthesiologists (ASA) physical status I or II patients scheduled for foot and ankle surgery with calf tourniquet under lateral popliteal sciatic nerve block were randomly assigned to receive 30 mL of either ropivacaine 0.75% or mepivacaine 1.5%. Time required for onset of sensory and motor block, resolution of motor blockade, onset of postsurgical pain, and time of first analgesic medication were recorded. RESULTS: The 2 groups were similar with regard to demographic variables and duration of surgery. Onset of sensory and motor block was significantly shorter in the mepivacaine group (9.9 +/- 3.3 min and 14.7 +/- 3.6 min, respectively) than in the ropivacaine group (18.1 +/- 6.1 min and 23.6 +/- 5.5 min, respectively) (P < 0.001). Resolution of motor block occurred later in the ropivacaine group than in the mepivacaine group (P < 0.001), and duration of postoperative analgesia was significantly longer in the ropivacaine group (19 +/- 3.4 h) compared with the mepivacaine group (5.9 +/- 1.1 h) (P < 0.001). Analgesic requirements were higher in mepivacaine group than in the ropivacaine group (P < 0.001). There were 2 failed blocks, one in each group. CONCLUSIONS: Both ropivacaine and mepivacaine provided effective sciatic nerve blockade. Mepivacaine 1.5% displayed a significantly shorter onset time than ropivacaine 0.75%. Postoperatively, ropivacaine 0.75% resulted in longer-lasting analgesia and less need for oral pain medication.
Assuntos
Amidas/administração & dosagem , Bloqueio Nervoso Autônomo/métodos , Articulação do Joelho/efeitos dos fármacos , Mepivacaína/administração & dosagem , Nervo Isquiático/efeitos dos fármacos , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Feminino , Humanos , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Ropivacaina , Nervo Isquiático/fisiologia , Estatísticas não ParamétricasRESUMO
BACKGROUND AND OBJECTIVES: The purpose of this study was to identify which of two motor responses of the foot (plantar flexion versus dorsiflexion) best predicts complete sensory blockade of the sciatic nerve when is used for lateral popliteal sciatic nerve block. METHODS: Thirty American Society of Anesthesiologist physical status I or II patients scheduled for foot and ankle surgery under lateral popliteal sciatic nerve block were enrolled in the study. During each block, the needle was placed to evoke one of the following motor responses of the foot: plantar flexion or dorsiflexion. Thirty milliliters of 0.75% ropivacaine was injected after the motor response was elicited at <0.5 mA. The sequence of elicited motor response was randomized. Sensory blockade of the areas of the foot innervated by the deep peroneal, superficial peroneal, posterior tibial, and sural nerves was checked in a blinded manner. Time required for onset of sensory and motor block of the foot was recorded. RESULTS: The 2 groups were similar with regard to demographic variables and type of surgery. The total of nerves blocked (deep and superficial peroneal, posterior tibial, and sural nerves) after elicited plantar flexion was greater (complete sensory block in 58 of 60 nerve distributions) than after elicited dorsiflexion (34 of 60 nerve distributions) (P <.05). Onset of complete sensory and motor blockade of the foot was faster after elicited plantar flexion (16.6 +/- 5.1 minutes, 20.1 +/- 5.1 minutes, respectively) than after elicited dorsiflexion (24.3 +/- 5.1 minutes, 28.1 +/- 5.0 min, P <.05). CONCLUSIONS: After stimulation of the sciatic nerve, plantar flexion better predicts complete sensory blockade of the foot than dorsiflexion when using the lateral approach to the popliteal fossa. The findings of the present study apply to a single injection of 30 mL of ropivacaine 0.75%.
Assuntos
Potencial Evocado Motor/efeitos dos fármacos , Pé/inervação , Bloqueio Nervoso/métodos , Nervo Isquiático/efeitos dos fármacos , Adolescente , Adulto , Idoso , Anestésicos Intravenosos/uso terapêutico , Potencial Evocado Motor/fisiologia , Feminino , Fentanila/uso terapêutico , Humanos , Masculino , Midazolam/uso terapêutico , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Nervo Isquiático/fisiologia , Estatísticas não ParamétricasRESUMO
BACKGROUND AND OBJECTIVES: The midfemoral approach to the sciatic nerve (MF) is a new technique that has been used for postoperative analgesia after knee surgery. The aim of the present study was to compare efficacy, performance time, and patient acceptance of the midfemoral approach to that of the lateral approach at the level of the popliteal fossa (popliteal block [PB]). METHODS: Sixty-three patients were enrolled in this prospective, randomized study. Thirty-two patients received a lateral sciatic nerve block (group PB) and 31 patients a midfemoral block (group MF). Ropivacaine 0.5% (30 mL) was used in both groups. RESULTS: The quality of nerve blockade was comparable in both groups. Onset of sensory block for peroneal and tibial nerves was significantly shorter in group MF than in group PB, 5 (1-20) minutes and 5 (1-20) minutes versus 10 (1-40) minutes and 10 (1-45) minutes, respectively. Onset of motor block in both territories was also shorter in group MF compared with PB, 6 (2-35) minutes and 5 (2-55) minutes versus 15 (2-60) minutes and 15 (2-60) minutes, respectively (P <.05). There was no difference in duration of sensory and motor blockade, 16 (7-32) hours versus 16 (6-43) hours and 16 (8-32) hours versus 16 (6-25) hours. There was no significant difference between both groups with respect to difficulty of nerve block performance. Patient discomfort during needle puncture was also similar. CONCLUSIONS: The midfemoral approach to the sciatic nerve for ankle and foot surgery resulted in a reliable anesthetic, comparable to that of the lateral popliteal approach. This technique is simple, safe, and provides postoperative analgesia as effective as that obtained with the lateral approach.
Assuntos
Amidas , Anestésicos Locais , Bloqueio Nervoso , Nervo Isquiático , Adulto , Idoso , Amidas/efeitos adversos , Anestésicos Locais/efeitos adversos , Estimulação Elétrica , Feminino , Humanos , Perna (Membro)/inervação , Perna (Membro)/cirurgia , Masculino , Pessoa de Meia-Idade , Neurônios Motores/efeitos dos fármacos , Neurônios Aferentes/efeitos dos fármacos , Procedimentos Ortopédicos , Medição da Dor , Aceitação pelo Paciente de Cuidados de Saúde , Ropivacaina , Decúbito DorsalRESUMO
BACKGROUND AND OBJECTIVES: In different peripheral nerve blocks, it has been speculated that needle guidance by ultrasound improves onset time and success rate compared with the more frequently used nerve stimulation-guided technique. In the present study, we tested the hypothesis that ultrasound guidance improves onset time of coracoid infraclavicular brachial plexus block (IBPB) when compared with a nerve stimulation-guided technique. METHODS: Seventy patients scheduled for hand or forearm surgery were randomly assigned to receive coracoid IBPB using either ultrasound guidance (group U, n = 35), or nerve stimulation (group S, n = 35). Patients were assessed for sensory and motor block every 5 mins after injection of local anesthetic. Onset time, the primary end point, was defined as the time required for complete sensory and motor block. Time required to perform the block, success rate, and time to resolution of motor blockade were also recorded (secondary end points). RESULTS: Onset of complete sensory and motor blockade was similar in the 2 groups (17 mins [8 mins] in group U and 19 mins [8 mins] in group S; P = 0.321). Time required to perform the block was shorter in group U (3 mins [1 min]) as compared with group S (6 mins [2 mins]; P < 0.0001). No differences were observed in success rate (89% in group U and 91% in group S; P = 0.881) and time to resolution of motor blockade (237 mins [45 mins] in group U and 247 mins [57 mins] in group S; P = 0.418). CONCLUSIONS: The present investigation demonstrates that ultrasound guidance and nerve stimulation provide similar onset time, success rate, and duration of motor blockade for coracoid IBPB; however, ultrasound guidance reduces the time required to perform the block.
Assuntos
Bloqueio Nervoso/métodos , Estimulação Elétrica Nervosa Transcutânea/instrumentação , Ultrassonografia de Intervenção/métodos , Plexo Braquial , Clavícula , Feminino , Antebraço/cirurgia , Mãos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Punções/métodos , Método Simples-Cego , Fatores de Tempo , Estimulação Elétrica Nervosa Transcutânea/métodos , Punho/cirurgiaRESUMO
PURPOSE OF REVIEW: Even though high thoracic epidural anesthesia has been shown to be highly efficacious in the control of symptoms in refractory angina, its general use is still restricted. In patients who undergo coronary revascularization, however, the technique is becoming more and more popular. The present review outlines the use of high thoracic epidural anesthesia in patients with ischemic heart disease who underwent coronary revascularization in order to further reveal high thoracic epidural anesthesia's low complication rate and to analyze why physicians still refrain from using it more frequently. RECENT FINDINGS: The incidence of severe hemodynamic complications after high thoracic epidural anesthesia is low in patients with coronary artery disease. The main advantage would be a myocardial sympathectomy leading to an improvement in the oxygen input-demand relationship. Likewise, a decrease in mortality due to respiratory complications could not be shown. In patients undergoing myocardial revascularization with full anticoagulation there is an increased risk of epidural hematoma formation. Its precise risk is difficult to evaluate. There is an overall low rate of epidural hematomas as a result of high thoracic epidural anesthesia. With the available data, the incidence has been estimated at between 1/1500 and 1/10,000. SUMMARY: Epidural anesthesia does not decrease mortality or the incidence of myocardial infarction after coronary artery bypass grafting. It reduces the incidence of arrhythmias and respiratory complications and improves the quality of analgesia. High thoracic epidural anesthesia has been shown to be a safe and efficient technique for refractory angina that reduces the frequency of ischemic events and improves the clinical condition of patients.
RESUMO
Labat's classic approach to the sciatic nerve has not been able to show which motor response of the foot provides a more frequent rate of complete sensory and motor block. In this prospective, randomized, double-blind study, we compared plantar flexion with dorsiflexion with regard to onset time and efficacy of sciatic nerve block using the classic posterior approach. A total of 80 patients undergoing hallux valgus repair were randomly allocated to receive sciatic nerve block after evoked plantar flexion (n=40) or dorsiflexion (n=40). Twenty milliliters of 0.75% ropivacaine was injected after the motor response was elicited at <0.5 mA. Success rate was defined as complete sensory and motor block in all sciatic nerve distributions associated with a pain-free surgery. Time required for onset of sensory and motor block of the foot was recorded. Success was more frequent after elicited plantar flexion (87.5%) than dorsiflexion (55%; P <0.05). Onset of complete sensory and motor block of the foot was faster after elicited plantar flexion (10 +/- 10 min and 13 +/- 10 min, respectively) compared with dorsiflexion (20 +/- 11 min and 24 +/- 12 min; P <0.05). We conclude that plantar flexion of the foot predicts a shorter onset time and a more frequent success rate than dorsiflexion with Labat's classic posterior sciatic nerve block.
Assuntos
Pé , Movimento/efeitos dos fármacos , Bloqueio Nervoso , Nervo Isquiático , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Potencial Evocado Motor/efeitos dos fármacos , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Estudos ProspectivosRESUMO
UNLABELLED: The two components of the sciatic nerve become more distant from one another in their course down the lower limb. This may have clinical implications if a small volume of local anesthetic is used with a single injection technique. In this prospective, randomized, double-blind study, we compared two different injection sites, 20 cm and 30 cm distal to the greater trochanter, in terms of onset time and success rate of sciatic nerve blockade after a single injection of 20 mL of 1.5% mepivacaine. Fifty patients undergoing foot surgery were randomly allocated to receive a lateral sciatic nerve blockade using one of 2 levels: 20 cm distal to the greater trochanter (group proximal; n = 25) and 30 cm distal to the greater trochanter (group distal; n = 25). Twenty milliliters of 1.5% mepivacaine was injected after a flexion plantar response was obtained at <0.5 mA. Time required for onset of sensory and motor blockade of the foot was recorded. Success rate was defined as complete sensory and motor blockade in all sciatic nerve distributions associated with a pain-free surgery. Onset of complete sensory and motor blockade was faster in group proximal (12 +/- 7 min and 15 +/- 8 min, respectively) compared with group distal (19 +/- 9 min and 23 +/- 9 min; P < 0.05). Group proximal also had a more frequent success rate compared with group distal (88% versus 56%, respectively; P < 0.05). It is concluded that in lateral sciatic nerve blockade, a more proximal approach to the sciatic nerve predicts a shorter onset time and more frequent success than a more distal injection site when a single injection and a small volume of local anesthetic is used. IMPLICATIONS: In lateral sciatic nerve blockade, a more proximal approach to the sciatic nerve provides shorter onset times and more frequent success than a more distal injection site when a single injection of 20 mL of mepivacaine 1.5% is used.
Assuntos
Mepivacaína/administração & dosagem , Bloqueio Nervoso/métodos , Nervo Isquiático , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Fêmur , Humanos , Injeções , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
PURPOSE OF REVIEW: The purpose of this review is to present the most important recent studies into the clinical use of peripheral nerve blocks for anesthesia and postoperative analgesia of the lower limb surgery. RECENT FINDINGS: There is increasing interest in lower extremity peripheral nerve blocks because of their potential advantages and concerns over interactions of centroneuraxis blocks and anticoagulants. Several authors have studied different approaches to the blockade of peripheral nerves with their advantages or disadvantages. Continuous peripheral nerve blocks have showed prolonged analgesia and great patient satisfaction with low side effects. Recent imaging techniques (e.g. ultrasound, magnetic resonance, tomography scans) have been developed to improve the performance of lower peripheral nerve blocks. Finally, complications of these techniques have been examined. SUMMARY: Introduction of new methods and techniques are increasing and improving the use of lower peripheral nerve blocks. These techniques are gaining interest after the important increase of the lower molecular weigh heparins.
RESUMO
PURPOSE: Neuraxial blockade is known to have a sedative effect, decreasing the need for inhalational and iv anesthetic agents. The purpose of the present study was to quantify the sedative effect of spinal anesthesia and to determine the time of maximum sedation. METHODS: This is an observational study in which 20 unsedated patients were scheduled to undergo urologic and orthopedic surgeries under spinal anesthesia. Patients with pre-existing neurological conditions or receiving psychotropic medications were excluded from the study. All received 1.5 mL (11.25 mg) of hyperbaric bupivacaine 0.75% intrathecally. No sedative or narcotic was administered intravenously or intrathecally. The Patient State Analyzer, (PSA-4000) was used to monitor sedation along with Observer's Assessment of Alertness and Sedation (OAA/S) scores every five minutes. Differences in patient state index (PSI) and OAA/S scores are expressed as median and range and were evaluated by Wilcoxon's signed rank test for non-parametric data; P < 0.05 was considered significant. PSI, OAA/S and time at lowest score are expressed as median(range). RESULTS: PSI scores decreased from baseline 99 (96-99) to 78 (56-87) at 35(14.5-54) min into the spinal anesthetic (P < 0.05). OAA/S scores decreased from baseline 5 to 4 (range 3-5) at the time of the lowest PSI scores (P < 0.05). CONCLUSIONS: In this elderly patient population, spinal anesthesia induced changes in the processed electroencephalogram with reduction in PSI and OAA/S scores. The reduction in afferent input to the reticular activating system could possibly explain the sedation that has been observed and the reduction in the PSA scores.
Assuntos
Raquianestesia , Anestésicos Locais/administração & dosagem , Conscientização/efeitos dos fármacos , Estado de Consciência/efeitos dos fármacos , Eletroencefalografia , Idoso , Nível de Alerta/efeitos dos fármacos , Bupivacaína/administração & dosagem , Eletroencefalografia/instrumentação , Feminino , Humanos , Injeções Espinhais , Masculino , Neurônios Aferentes/efeitos dos fármacos , Variações Dependentes do Observador , Procedimentos Ortopédicos , Estatísticas não Paramétricas , Fatores de Tempo , Procedimentos Cirúrgicos UrológicosRESUMO
PURPOSE: Following release of a double tourniquet for intravenous regional anesthesia (IVRA), ropivacaine was shown to have a longer duration of action and less central nervous system (CNS) side effects than lidocaine. This study examines the correlation of CNS side effects to plasma levels of lidocaine 0.5% and ropivacaine 0.2% when injected intravenously for IVRA. METHODS: In a double-blind, cross-over study, ten volunteers received IVRA with 40 mL ropivacaine 0.2% or lidocaine 0.5% at least four days apart. Both cuffs of a double-cuff tourniquet remained inflated until they could no longer be tolerated. The incidence, duration and intensity of CNS side effects were recorded at three, ten, and 30 min after tourniquet release and correlated with simultaneous venous blood samples. RESULTS: There was a lower incidence of CNS side effects with ropivacaine (6/10 volunteers) when compared to lidocaine (10/10 volunteers). There was also less duration of these side effects (mean +/- SD, 5.1 +/- 5.2 min vs 11.7 +/- 6.7 min). Measured total plasma levels were highest at ten minutes with ropivacaine 0.2% (1.2 +/- 0.3 microg.mL(-1)) and at three minutes with lidocaine 0.5% (1.7 +/- 0.6 microg.mL(-1)). Peak CNS symptoms correlated with measured venous plasma levels for lidocaine, but occurred earlier with ropivacaine. CONCLUSIONS: We observed a lower incidence of CNS side effects with ropivacaine as compared to lidocaine. Although ropivacaine's greater lipid solubility should, theoretically, lead to more CNS side effects, this was, likely, offset by slower release from tissues and lesser percentage of unbound (free) drug.