The effect of wide-awake anesthesia, intravenous regional anesthesia, and infraclavicular brachial plexus block on cost and clinical scores of patients undergoing hand surgery.

The aim of our study was to compare the clinical results and costs of wide-awake local anesthesia no tourniquet (WALANT), intravenous regional anesthesia (IVRA), and infraclavicular brachial plexus block (IC-BPB). The patients were divided into WALANT, IVRA, IC-BPB groups, each with 50 patients. Demographic information, induction time, use of sedation, number of patients who were converted to general anesthesia, time in postanesthesia care unit (PACU), amount of bleeding during surgery, presence of tourniquet pain, hand motor function during surgery, time to onset of postanesthesia pain, discharge time, complications, and anesthesia costs were compared. Sedation was given to 12 IC-BPB patients, 9 IVRA patients and 5 WALANT patients. Of these patients, 6 undergoing IC-BPB, 5 undergoing IVRA and 4 undergoing WALANT were converted to general anesthesia (p = 0.80). PACU time and anesthesia costs were the least in the WALANT group, followed by the IVRA group (p < 0.001, p < 0.001). Intraoperative active voluntary movements were best preserved in the WALANT group; however, bleeding was highest in the WALANT group (p < 0.001, p < 0.001). Tourniquet pain was the higher in the IVRA groups, while postoperative pain in the surgical area developed the fastest in this same group (p = 0.029, p < 0.001). Time to discharge was similar in WALANT and IVRA groups, and the longest in the IC-BPB (p < 0.001) group. There was no difference among the groups in terms of patient satisfaction (p = 0.085, p = 0.242 for the first and second survey question). In the current study, WALANT appears to be a suitable alternative to IVRA and IC-BPB methods, with better preservation of active intraoperative movement, lower cost, and shorter time spent in PACU at the expense of higher bleeding.

Patients' Perspective on Carpal Tunnel Release with WALANT or Intravenous Regional Anesthesia.

BACKGROUND: The authors conducted a prospective study to compare patients' intraoperative experience of open carpal tunnel release under "wide awake, local anesthesia, no tourniquet" (WALANT) on the one hand and intravenous regional anesthesia on the other. The authors hypothesized that WALANT would offer a better intraoperative experience than intravenous regional anesthesia. METHODS: Twenty-four patients with bilateral carpal tunnel syndrome had one hand operated on using WALANT and the contralateral hand with the intravenous regional anesthesia method. At the postoperative second hour, patients completed a questionnaire to quantify their pain levels on a numerical rating scale and compare the operation with dental procedures. They were also asked about their expectations and feelings about reoperation with the anesthesia methods. The results were compared for the two anesthesia methods. RESULTS: There were no significant differences between numerical rating scale pain values during anesthetic administration or for surgical site pain on the WALANT and intravenous regional anesthesia sides. Patients reported moderate tourniquet pain for intravenous regional anesthesia sides. For WALANT sides, a significantly higher number of patients reported carpal tunnel release to be an easier procedure than dental procedures (91.6 percent WALANT and 37.5 percent intravenous regional anesthesia). For WALANT sides, a significantly higher number of patients reported carpal tunnel release to be an easier procedure than they expected (91.6 percent WALANT and 50 percent intravenous regional anesthesia). For the reoperation, 83.3 percent of patients preferred WALANT, 8.3 percent preferred intravenous regional anesthesia, and 8.3 percent reported no preference. CONCLUSIONS: WALANT offered a better intraoperative experience. Tourniquet pain, preoperative preparation basics, and the extended anesthesia duration are likely the major drawbacks of the intravenous regional anesthesia method.

Feasibility of Fully Automated Hypnosis, Analgesia, and Fluid Management Using 2 Independent Closed-Loop Systems During Major Vascular Surgery: A Pilot Study.

Automated titration of intravenous anesthesia and analgesia using processed electroencephalography monitoring is no longer a novel concept. Closed-loop control of fluid administration to provide goal-directed fluid therapy has also been increasingly described. However, simultaneously combining 2 independent closed-loop systems together in patients undergoing major vascular surgery has not been previously detailed. The aim of this pilot study was to evaluate the clinical performance of fully automated hypnosis, analgesia, and fluid management using 2 independent closed-loop controllers in patients undergoing major vascular surgery before implementation within a larger study evaluating true patient outcomes.

[Effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients after target-controlled induction].

OBJECTIVE: To observe the clinical effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients who underwent abdominal external hernia surgery at the time of consciousness and pain disappearing by target-controlled infusion (TCI) and bispectral index (BIS). METHODS: Fifty patients who underwent elective abdominal hernia surgery were randomly assigned into an observation group and a control group, 25 cases in each one. In the observation group, 30 minutes before anesthesia induction, Fugugou (Extra), Gan (CO12), Pizhixia (AT4), and Shenmen (TF4) were embedded by auricular needles until the end of surgery, 10 times of counter press each point. In the control group, the same amount of auricular tape was applied until the end of surgery at the same points without stimulation 30 minutes before anesthesia induction. Patients in the two groups were given total intravenous anesthesia, and BIS was monitored by BIS anesthesia depth monitor. Propofol was infused by TCI at a beginning concentration of 1.5µg/L and increased by 0.3µg/L every 30s until the patients lost their consciousness. After that, remifentanil was infused by TCI at a beginning concentration of 2.0µg/L and increased by 0.3µg/L every 30s until the patients had no body reaction to pain stimulation (orbital reflex). Indices were recorded, including mean arterial pressure (MAP), heart rate (HR) and the BIS values, at the time of T0 (entering into the operation room), T1 (losing consciousness) and T2 (pain relief), the plasma and effect site concentrations of propofol at T1, the plasma and effect site concentrations of remifentanil at T2. After surgery we recorded the total amounts of propofol and remifentanil, surgery time and anesthesia time. RESULTS: At T1 and T2, MAP and HR of the observation group were higher than those of the control group (P<0.05, P<0.01). At T1, the plasma and effect site concentrations of propofol in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). At T2, the plasma and effect site concentrations of remifentanil in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). There was no significant difference in BIS values at T1 and T2 between the two groups (bothP>0.05). There was no significant difference in operation time and anesthesia time between the two groups (bothP>0.05). The total amount of remifentanil in the observation group was significantly lower than that in the control group (P<0.01). There was no significant difference in the total amount of propofol between the two groups (P>0.05). CONCLUSIONS: Ear points embedding combined with propofol-remifentanil TCI could reduce the plasma and effect site concentrations of propofol and remifentanil and the total amount of remifentanil in elderly patients with extra-abdominal hernia surgery, and had the effect of assisting sedation and analgesia.

A Review of Modern Control Strategies for Clinical Evaluation of Propofol Anesthesia Administration Employing Hypnosis Level Regulation.

Regulating the depth of hypnosis during surgery is one of the major objectives of an anesthesia infusion system. Continuous administration of Propofol infusion during surgical procedures is essential but it unduly increases the load of an anesthetist working in a multitasking scenario in the operation theatre. Manual and target controlled infusion systems are not appropriate to handle instabilities like blood pressure and heart rate changes arising due to interpatient and intrapatient variability. Patient safety, large interindividual variability, and less postoperative effects are the main factors motivating automation in anesthesia administration. The idea of automated system for Propofol infusion excites control engineers to come up with more sophisticated systems that can handle optimum delivery of anesthetic drugs during surgery and avoid postoperative effects. A linear control technique is applied initially using three compartmental pharmacokinetic and pharmacodynamic models. Later on, sliding mode control and model predicative control achieve considerable results with nonlinear sigmoid model. Chattering and uncertainties are further improved by employing adaptive fuzzy control and H∞ control. The proposed sliding mode control scheme can easily handle the nonlinearities and achieve an optimum hypnosis level as compared to linear control schemes, hence preventing mishaps such as underdosing and overdosing of anesthesia.

Regulation of hypnosis in Propofol anesthesia administration based on non-linear control strategy / Controle da hipnose na administração de propofol com base na estratégia de controle não linear

Abstract Continuous adjustment of Propofol in manual delivery of anesthesia for conducting a surgical procedure overburdens the workload of an anesthetist who is working in a multi-tasking scenario. Going beyond manual administration and Target Controlled Infusion, closed-loop control of Propofol infusion has the potential to offer several benefits in terms of handling perturbations and reducing the effect of inter-patient variability. This paper proposes a closed-loop automated drug administration approach to control Depth Of Hypnosis in anesthesia. In contrast with most of the existing research on anesthesia control which makes use of linear control strategies or their improved variants, the novelty of the present research lies in applying robust control strategy i.e. Sliding Mode Control to accurately control drug infusion. Based on the derived patient's model, the designed controller uses measurements from EEG to regulate DOH on Bispectral Index by controlling infusion rate of Propofol. The performance of the controller is investigated and characterized with real dataset of 8 patients undergoing surgery. Results of this in silico study indicate that for all the patients, with 0% overshoot observed, the steady state error lies in between ±5. Clinically, this implies that in all the cases, without any overdose, the controller maintains the desired DOH level for smooth conduction of surgical procedures.

Resumo O ajuste contínuo de propofol na administração manual de anestesia para um procedimento cirúrgico onera a carga de trabalho de anestesistas que trabalham em ambiente multitarefa. Indo além da administração manual e da infusão alvo-controlada (IAC), o controle de circuito fechado da infusão de propofol tem o potencial de oferecer vários benefícios em termos de manejo das perturbações e reduzir o efeito da variabilidade interpaciente. Este artigo propõe uma abordagem para a administração automatizada de drogas em circuito fechado para controlar a profundidade da hipnose (PDH) em anestesia. Em contraste com a maioria das pesquisas existentes sobre o controle da anestesia que usam estratégias de controle linear ou de suas variantes melhoradas, a novidade da presente pesquisa reside na aplicação de uma estratégia de controle consistente; isto é, o Controle por Modos Deslizantes (CMD) para controlar com precisão a infusão da droga. Com base no modelo derivado do paciente, o controlador projetado usa as medições do EEG para regular a PDH no Bispectral Index (BIS), controla a taxa de infusão de propofol. O desempenho do controlador é investigado e caracterizado com um conjunto de dados reais de oito pacientes submetidos à cirurgia. Os resultados deste estudo in silico indicam que, para todos os pacientes, com 0% de excesso observado, o erro de estado estacionário fica entre ± 5. Clinicamente, isso implica que em todos os casos, sem qualquer sobredosagem, o controlador mantém o nível desejado de PDH para a condução tranquila dos procedimentos cirúrgicos.

[Regulation of hypnosis in Propofol anesthesia administration based on non-linear control strategy]. / Controle da hipnose na administração de propofol com base na estratégia de controle não linear.

Continuous adjustment of Propofol in manual delivery of anesthesia for conducting a surgical procedure overburdens the workload of an anesthetist who is working in a multi-tasking scenario. Going beyond manual administration and Target Controlled Infusion, closed-loop control of Propofol infusion has the potential to offer several benefits in terms of handling perturbations and reducing the effect of inter-patient variability. This paper proposes a closed-loop automated drug administration approach to control Depth Of Hypnosis in anesthesia. In contrast with most of the existing research on anesthesia control which makes use of linear control strategies or their improved variants, the novelty of the present research lies in applying robust control strategy i.e. Sliding Mode Control to accurately control drug infusion. Based on the derived patient's model, the designed controller uses measurements from EEG to regulate DOH on Bispectral Index by controlling infusion rate of Propofol. The performance of the controller is investigated and characterized with real dataset of 8 patients undergoing surgery. Results of this in silico study indicate that for all the patients, with 0% overshoot observed, the steady state error lies in between ±5. Clinically, this implies that in all the cases, without any overdose, the controller maintains the desired DOH level for smooth conduction of surgical procedures.

Spontaneous ventilation anaesthesia: total intravenous anaesthesia with local anaesthesia or thoracic epidural anaesthesia for thoracoscopic bullectomy.

OBJECTIVES: At present, few data exist regarding the comparisons of perioperative outcomes and recurrence of spontaneous ventilation (SV) video-assisted thoracic surgery (VATS) bullectomy using total intravenous anaesthesia (TIVA) with local anaesthesia (LA) or thoracic epidural anaesthesia (TEA). We evaluated the feasibility and safety of TIVA with LA in the management of primary spontaneous pneumothorax (PSP). METHODS: We conducted a single-institution retrospective analysis of patients undergoing VATS bullectomy between July 2011 and May 2015; 240 patients were included for analysis. Preoperative, intraoperative and postoperative variables of patients undergoing VATS bullectomy using TIVA-TEA (n = 140) were compared with those using TIVA-LA (n = 100). RESULTS: Baseline demographics were similar between groups. No patients in either group required conversion to thoracotomy. Three patients (TIVA-TEA: 2; TIVA-LA: 1) required conversion to intubated general anaesthesia. Both groups had comparable surgical duration, estimated blood loss, peak EtCO2 and lowest intraoperative SpO2 level. Postoperatively, thoracic drainage volume, duration of chest tube drainage and hospitalization cost did not differ between groups. The incidence of postoperative complications between groups was not significant (2% for TIVA-TEA vs 2% for TIVA-LA, P = 1.00). Pneumothorax recurrence rate was 3% in TIVA-TEA cases (n = 4) and 2% in TIVA-LA cases (n = 2). CONCLUSIONS: SV-VATS bullectomy using TIVA with LA or TEA is technically feasible and safe. Both groups have comparable short-term outcomes and recurrence rates; TIVA-LA seems a valid alternative to TIVA-TEA for the surgical management of PSP under SV.

Ibuprofeno intravenoso: experiencia clínica en el tratamiento del dolor postoperatorio / Intravenous ibuprofen: clinic experience in the treatment of postoperative pain

El dolor postoperatorio de intensidad alta o extrema tiene una incidencia publicada cercana al 30 % de los pacientes quirúrgicos, siendo su principal preocupación, incluso más relevante que los resultados satisfactorios o no que pudiera tener el procedimiento en la resolución de su enfermedad. Los AINE son los fármacos más prescritos en el mundo para el tratamiento del dolor agudo y crónico de diferentes causas. El ibuprofeno es un analgésico ampliamente utilizado en la prevención y tratamiento del dolor. Recientemente, su forma intravenosa ha sido aprobada por la FDA (www.accessdata.fda.gov) para el tratamiento del dolor leve a moderado y moderado a severo complementario a la analgesia opioide. Adicionalmente, ha sido aprobado para la reducción de la fiebre. Dado su potencial como adyuvante en la analgesia multimodal, se realizó una revisión acerca del uso perioperatorio del ibuprofeno intravenoso, analizando la literatura disponible en inglés y español en PubMed y Ovid MEDLINE hasta diciembre 2015. Se incluyeron datos farmacocinéticos y farmacodinámicos provenientes de pacientes de diferentes edades, así como estudios clínicos, incluyendo aquellos en los que se cuantificó el uso de opioides en el periodo postoperatorio, analizando la sinergia entre ambos tipos de analgésicos. El ibuprofeno intravenoso ofrece ventajas sobre la presentación oral, siendo una alternativa a la limitada disponibilidad de AINE endovenosos como parte de la analgesia multimodal perioperatoria (AU)

About 30 % of surgical patients report high or extreme intensity postoperative pain as their main concern, which is even more relevant than satisfactory surgery results. NSAIDs are the most commonly prescribed drugs worldwide for the treatment of acute and chronic pain. Ibuprofen is widely used in prevention and treatment of pain. Recently, intravenous ibuprofen has been approved by the FDA (www.accessdata.fda.gov) for the management of mild-moderate pain and management of moderate-severe pain complementary to opioid analgesia. Additionally, has been approved for fever reduction. Given its potential as adjuvant therapy in multimodal analgesia, a review of the perioperative use of intravenous ibuprofen was conducted by analyzing literature available in English and Spanish in PubMed and Ovid MEDLINE through December 2015. The review included pharmacokinetic and pharmacodynamic data from patients of different ages as well as clinical studies where the use of opioids was quantified in the postoperative period and the synergy between these two types of drugs was analyzed. Intravenous ibuprofen offers advantages over oral presentation and is an alternative to the limited availability of intravenous NSAIDs as part of multimodal perioperative analgesia (AU)

[POSSIBILITY OF ENHANCING OF THE TRANSPAPILLARY INTERVENTIONS EFFICACY, APPLYING OPTIMIZATION OF THEIR ANESTHESIOLOGICAL SUPPORT].

In 2015 yr еndoscopic transpapillary interventions (ЕТI), performed for diseases of the hepatopancreatoduodenal zone organs, were done in 697 patients. In 315 (45.2%) of them ЕТI were diagnostic, in 382 (54.8%) ­ performed with treatment objective. Меdicinal support for the ЕТI conduction in 631 (90.5%) patients have included conduction of superficial sedation and local anesthesia of pharynx. Аnesthesiological support was applied in 66 (9.5%) patients, including total intravenous anesthesia ­ in 11 (16.6%), еndotracheal narcosis ­ in 55 (83.4%). Using of general anesthesia in comparison to superficial sedation creates more favorable conditions for the ЕТI performance, what have permitted to reduce their duration and complications rate twice.

Evaluation of the brain anaesthesia response monitor during anaesthesia for cardiac surgery: a double-blind, randomised controlled trial using two doses of fentanyl.

The brain anaesthesia response (BAR) monitor uses a method of EEG analysis, based on a model of brain electrical activity, to monitor the cerebral response to anaesthetic and sedative agents via two indices, composite cortical state (CCS) and cortical input (CI). It was hypothesised that CCS would respond to the hypnotic component of anaesthesia and CI would differentiate between two groups of patients receiving different doses of fentanyl. Twenty-five patients scheduled to undergo elective first-time coronary artery bypass graft surgery were randomised to receive a total fentanyl dose of either 12 µg/kg (fentanyl low dose, FLD) or 24 µg/kg (fentanyl moderate dose, FMD), both administered in two divided doses. Propofol was used for anaesthesia induction and pancuronium for intraoperative paralysis. Hemodynamic management was protocolised using vasoactive drugs. BIS, CCS and CI were simultaneously recorded. Response of the indices (CI, CCS and BIS) to propofol and their differences between the two groups at specific points from anaesthesia induction through to aortic cannulation were investigated. Following propofol induction, CCS and BIS but not CI showed a significant reduction. Following the first dose of fentanyl, CI, CCS and BIS decreased in both groups. Following the second dose of fentanyl, there was a significant reduction in CI in the FLD group but not the FMD group, with no significant change found for BIS or CCS in either group. The BAR monitor demonstrates the potential to monitor the level of hypnosis following anaesthesia induction with propofol via the CCS index and to facilitate the titration of fentanyl as a component of balanced anaesthesia via the CI index.

Comparisons of Electroencephalographically Derived Measures of Hypnosis and Antinociception in Response to Standardized Stimuli During Target-Controlled Propofol-Remifentanil Anesthesia.

BACKGROUND: Current electroencephalogram (EEG)-derived measures provide information on cortical activity and hypnosis but are less accurate regarding subcortical activity, which is expected to vary with the degree of antinociception. Recently, the neurophysiologically based EEG measures of cortical input (CI) and cortical state (CS) have been shown to be prospective indicators of analgesia/antinociception and hypnosis, respectively. In this study, we compared CI and an alternate measure of CS, the composite cortical state (CCS), with the Bispectral Index (BIS) and another recently developed measure of antinociception, the composite variability index (CVI). CVI is an EEG-derived measure based on a weighted combination of BIS and estimated electromyographic activity. By assessing the relationship between these indices for equivalent levels of hypnosis (as quantified using the BIS) and the nociceptive-antinociceptive balance (as determined by the predicted effect-site concentration of remifentanil), we sought to evaluate whether combining hypnotic and analgesic measures could better predict movement in response to a noxious stimulus than when used alone. METHODS: Time series of BIS and CVI indices and the raw EEG from a previously published study were reanalyzed. In our current study, the data from 80 patients, each randomly allocated to a target hypnotic level (BIS 50 or BIS 70) and a target remifentanil level (Remi-0, -2, -4 or -6 ng/mL), were included in the analysis. CCS, CI, BIS, and CVI were calculated or quantified at baseline and at a number of intervals after the application of the Observer's Assessment of Alertness/Sedation scale and a subsequent tetanic stimulus. The dependency of the putative measures of antinociception CI and CVI on effect-site concentration of remifentanil was then quantified, together with their relationship to the hypnotic measures CCS and BIS. Finally, statistical clustering methods were used to evaluate the extent to which simple combinations of antinociceptive and hypnotic measures could better detect and predict response to stimulation. RESULTS: Before stimulation, both CI and CVI differentiated patients who received remifentanil from those who were randomly allocated to the Remi-0 group (CI: Cohen's d = 0.65, 95% confidence interval, 0.48-0.83; CVI: Cohen's d = 0.72, 95% confidence interval, 0.56-0.88). Strong correlations between BIS and CCS were found (at different periods: 0.55 < R2 < 0.68, P < 0.001). Application of the Observer's Assessment of Alertness/Sedation stimulus was associated with changes in CI and CCS, whereas, subsequent to the application of both stimuli, changes in all measures were seen. Pairwise combinations of CI and CCS showed higher sensitivity in detecting response to stimulation than CVI and BIS combined (sensitivity [99% confidence interval], 75.8% [52.7%-98.8%] vs 42% [15.4%-68.5%], P = 0.006), with specificity for CI and CCS approaching significance (52% [34.7%-69.3%] vs 24% [9.1%-38.9%], P = 0.0159). CONCLUSIONS: Combining electroencephalographically derived hypnotic and analgesic quantifiers may enable better prediction of patients who are likely to respond to tetanic stimulation.

Combining interscalene brachial plexus block with intravenous-inhalation combined anesthesia for upper extremity fractures surgery: a randomized controlled trial.

BACKGROUND: A parallel-group randomized controlled trial (RCT) was conducted to evaluate the effect of combining the interscalene brachial plexus block (IBPB) with Intravenous-inhalation combined anesthesia to isolated Intravenous-inhalation anesthesia in the upper extremity fractures surgery of elderly patients. METHODS: One hundred elderly patients who underwent upper extremity surgery were randomly assigned to received isolated Intravenous-inhalation combined anesthesia (group CI, n = 50) and IBPB associated with Intravenous-inhalation combined anesthesia (group NB, n = 50). Associated side effects, recovery time after operation, as well as the dose of intraoperative vasoactive agents and auxiliary drugs were noted. RESULTS: The two groups were not significantly different in gender (P = 0.539), ages (P = 0.683) and weight (P = 0.212). Five patients (10%) in the group NB and 17 patients (34%) in the group CI suffered from preoperative hypotension (P = 0.004). Besides, lower incidence of other adverse effects such as mental stress, incision pain and hypertension were also found in the group NB; however, the differences were not statistically significant (P > 0.05). The consumption of general anesthetics in the group NB was significantly less than that of the group CI (propofol, P = 0.004; lsoflurane, P < 0.001), and the recovery time of the group NB was significantly shorter than that of the group CI (P = 0.020). CONCLUSION: Combining IBPB with Intravenous-inhalation combined anesthesia in elderly patients hold a greater potential for upper extremity fractures surgery due to its improved clinical effectiveness and fewer side effects.

Comparison of the effect of lidocaine adding dexketoprofen and paracetamol in intravenous regional anesthesia.

OBJECTIVE: Comparison of dexketoprofen and paracetamol added to the lidocaine in Regional Intravenous Anesthesia in terms of hemodynamic effects, motor and sensorial block onset times, intraoperative VAS values, and analgesia requirements. METHOD: The files of 73 patients between 18 and 65 years old in the ASA I-II risk group who underwent hand and forearm surgery were analyzed and 60 patients were included in the study. Patients were divided into 3 groups: Group D (n = 20), 3 mg/kg 2% lidocaine and 50 mg/2 mL dexketoprofen trometamol; Group P (n = 20), 3 mg/kg 2% lidocaine and 3 mg/kg paracetamol; Group K (n = 20), 3 mg/kg 2% lidocaine. Demographic data, motor and sensorial block times, heart rate, mean blood pressure, VAS values, and intraoperative and postoperative analgesia requirements were recorded. RESULTS: Sensorial and motor block onset durations of Group K were significantly longer than other groups. Motor block termination duration was found to be significantly longer in Group D than in Group K. VAS values of Group K were found higher than other groups. There was no significant difference in VAS values between Group D and Group P. Analgesia requirement was found to be significantly more in Group K than in Group P. There was no significant difference between the groups in terms of heart rates and mean arterial pressures. CONCLUSION: We concluded that the addition of 3 mg/kg paracetamol and 50 mg dexketoprofen to lidocaine as adjuvant in Regional Intravenous Anesthesia applied for hand and/or forearm surgery created a significant difference clinically.

Anestesia regional intravenosa con anestésicos locales de larga duración. Actualización / Intravenous regional anesthesia with long-acting local anesthetics. An update

La anestesia regional intravenosa es una técnica ampliamente utilizada en intervenciones quirúrgicas de poca duración, especialmente en las extremidades superiores, y menos frecuentemente en las inferiores. Su primera aparición data de principios del siglo xx, cuando Bier inyectó procaína como anestésico local. La ejecución de esta técnica como anestesia quirúrgica no ha cambiado mucho desde entonces, si bien diversos fármacos, particularmente anestésicos locales de larga duración como ropivacaína y levobupivacaína en bajas concentraciones, han sido introducidos en la práctica clínica. Además, fármacos como opioides, bloqueantes neuromusculares, paracetamol, neostigmina, magnesio, ketamina, keterolaco y clonidina han sido investigados como complementarios a los anestésicos locales, y parecen aportar beneficios en cuanto al inicio de la anestesia y una más larga duración de la analgesia perioperatoria. Este artículo de revisión intenta dar una visión global de los conocimientos actuales en anestésicos locales de larga duración para anestesia regional intravenosa (AU)

Intravenous regional anesthesia is a widely used technique for brief surgical interventions, primarily on the upper limbs and less frequently, on the lower limbs. It began being used at the beginning of the 20th century, when Bier injected procaine as a local anesthetic. The technique to accomplish anesthesia has not changed much since then, although different drugs, particularly long-acting local anesthetics, such as ropivacaine and levobupivacaine in low concentrations, were introduced. Additionally, drugs like opioids, muscle relaxants, paracetamol, neostigmine, magnesium, ketamine, clonidine, and ketorolac, have all been investigated as adjuncts to intravenous regional anesthesia, and were found to be fairly useful in terms of an increased onset of operative anesthesia and longer lasting perioperative analgesia. The present article provides an overview of current knowledge with emphasis on long-acting local anesthetic drugs (AU)

Spectral entropy as a measure of hypnosis and hypnotic drug effect of total intravenous anesthesia in children during slow induction and maintenance.

BACKGROUND: We evaluated whether spectral entropy (SpE) can measure the depth of hypnosis and the hypnotic drug effect in children during total intravenous anesthesia. METHODS: Sixty healthy children, aged 3-16 yr, were studied. Anesthesia was induced with an increasing target controlled infusion of propofol, and maintained by a stable remifentanil infusion and variable concentrations of target controlled infusion propofol. Depth of hypnosis was assessed according to the University of Michigan Sedation Scale (UMSS). Estimated plasma (C(p)) and pseudo effect site (C(eff)) propofol concentrations reflected the hypnotic drug effect. Patients were stratified to three age groups. The correlations between SpE versus UMSS, C(p), and C(eff) were analyzed by Prediction Probability (P(k)). The pharmacodynamic relationship between SpE and C(p), and the differences of SpE values between the age groups at the corresponding UMSS levels, were studied. RESULTS: Respective mean P(k) values for the youngest, middle, and oldest age groups were: 1) during induction: SpE versus UMSS 0.87, 0.87, and 0.93; SpE versus C(p) 0.92, 0.95, and 0.97; and SpE versus C(eff) 0.88, 0.94, and 0.95; 2) during maintenance: SpE versus C(eff) 0.86, 0.75, and 0.81. The pharmacodynamic analysis determined an association between SpE and C(p) that followed the E(max) model closely. There were significant differences in SpE values between age groups at corresponding UMSS sedation levels. CONCLUSIONS: SpE measures the level of hypnosis and hypnotic drug effect in children during total intravenous anesthesia. There is an age dependency associated with SpE. Anesthesia should not be steered solely on the basis of SpE.

Comparison between local anaesthesia with remifentanil and total intravenous anaesthesia for operative hysteroscopic procedures in day surgery.

BACKGROUND: This study aimed at comparing total i.v. anaesthesia (TIVA) with monitored anaesthesia care (MAC) during day-surgery operative hysteroscopy regarding: operation time, time to mobilization and discharge, and patient satisfaction. METHODS: Ninety-one healthy women were randomized to MAC with paracervical local anaesthesia and remifentanil or to TIVA with propofol and remifentanil. Time from arrival to leaving the operating theatre, time from arrival in the recovery room to mobilization and discharge readiness, and patient satisfaction with MAC and TIVA were observed. RESULTS: Time from arrival to leaving the operating theatre showed no significant difference between groups (P=0.6). The time to mobilization {MAC: 53 min [inter-quartile range (IQR) 40-83], TIVA: 69 min (IQR 52-96) (P=0.017)} and the total time from arrival to discharge readiness [MAC: 118 min (IQR 95-139), TIVA: 138 (IQR 120-158) (P=0.0009)] were significantly reduced for patients in the MAC group. More patients in the MAC group 45 (91.8%) than in the TIVA group 24 (64.9%) responded positively to the question: would you like to receive the same kind of anaesthesia for a similar procedure in the future? (P=0.003). CONCLUSIONS: Paracervical local anaesthesia combined with remifentanil is suitable for operative hysteroscopy in day surgery.

[Outpatient or short-stay videothoracoscopy-assisted thoracic sympathectomy: anesthesia in 445 cases]. / Anestesia para simpatectomía torácica por videotoracoscopia en régimen ambulatorio o corta estancia: experiencia en 445 casos.

OBJECTIVE: To demonstrate the safety of outpatient or short-stay bilateral videothoracoscopy-assisted thoracic sympathectomy. PATIENTS AND METHODS: The medical records of 445 who underwent bilateral videothoracoscopy-assisted thoracic sympathectomy were reviewed; the same protocols were used to guide these outpatient or short-stay procedures in all cases. Intravenous anesthesia was provided. An orotracheal tube allowed for carrying out the sympathectomy procedure during short periods of apnea. A 2% lidocaine solution was infused through the thoracic drains, which were removed soon after surgery. Data on intraoperative respiratory variables, pain, and intra- and postoperative complications were gathered. The data for patients undergoing the procedure on an outpatient or short-stay basis were compared. RESULTS: No significant differences in demographic or perioperative variables were found between the 2 groups. In 3.6% of the patients in the series, there was a record of a postoperative pulmonary complication: 4 therapeutic minithoracotomies; 1 subcutaneous emphysema without radiologic changes; 9 residual pneumothoraces, 2 requiring pleural drainage; 1 chylothorax; and 1 delayed hemothorax. With the exception of the late-developing hemothorax, all complications were diagnosed and treated in the immediate postoperative period. In the outpatient surgery group, unplanned admissions because of patient refusal to leave occurred in 6.5% of the cases. CONCLUSION: The low incidence of complications, and especially the finding that complications are detected in the early recovery period, indicate that this procedure can be performed on an outpatient basis.