Comparison between epidural and intravenous analgesia effects on disease-free survival after colorectal cancer surgery: a randomised multicentre controlled trial.

BACKGROUND: Thoracic epidural analgesia (TEA) has been suggested to improve survival after curative surgery for colorectal cancer compared with systemic opioid analgesia. The evidence, exclusively based on retrospective studies, is contradictory. METHODS: In this prospective, multicentre study, patients scheduled for elective colorectal cancer surgery between June 2011 and May 2017 were randomised to TEA or patient-controlled i.v. analgesia (PCA) with morphine. The primary endpoint was disease-free survival at 5 yr after surgery. Secondary outcomes were postoperative pain, complications, length of stay (LOS) at the hospital, and first return to intended oncologic therapy (RIOT). RESULTS: We enrolled 221 (110 TEA and 111 PCA) patients in the study, and 180 (89 TEA and 91 PCA) were included in the primary outcome. Disease-free survival at 5 yr was 76% in the TEA group and 69% in the PCA group; unadjusted hazard ratio (HR): 1.31 (95% confidence interval [CI]: 0.74-2.32), P=0.35; adjusted HR: 1.19 (95% CI: 0.61-2.31), P=0.61. Patients in the TEA group had significantly better pain relief during the first 24 h, but not thereafter, in open and minimally invasive procedures. There were no differences in postoperative complications, LOS, or RIOT between the groups. CONCLUSIONS: There was no significant difference between the TEA and PCA groups in disease-free survival at 5 yr in patients undergoing surgery for colorectal cancer. Other than a reduction in postoperative pain during the first 24 h after surgery, no other differences were found between TEA compared with i.v. PCA with morphine.

Inhalational versus Intravenous Induction of Anesthesia in Children with a High Risk of Perioperative Respiratory Adverse Events: A Randomized Controlled Trial.

BACKGROUND: Limited evidence suggests that children have a lower incidence of perioperative respiratory adverse events when intravenous propofol is used compared with inhalational sevoflurane for the anesthesia induction. Limiting these events can improve recovery time as well as decreasing surgery waitlists and healthcare costs. This single center open-label randomized controlled trial assessed the impact of the anesthesia induction technique on the occurrence of perioperative respiratory adverse events in children at high risk of those events. METHODS: Children (N = 300; 0 to 8 yr) with at least two clinically relevant risk factors for perioperative respiratory adverse events and deemed suitable for either technique of anesthesia induction were recruited and randomized to either intravenous propofol or inhalational sevoflurane. The primary outcome was the difference in the rate of occurrence of perioperative respiratory adverse events between children receiving intravenous induction and those receiving inhalation induction of anesthesia. RESULTS: Children receiving intravenous propofol were significantly less likely to experience perioperative respiratory adverse events compared with those who received inhalational sevoflurane after adjusting for age, sex, American Society of Anesthesiologists physical status and weight (perioperative respiratory adverse event: 39/149 [26%] vs. 64/149 [43%], relative risk [RR]: 1.7, 95% CI: 1.2 to 2.3, P = 0.002, respiratory adverse events at induction: 16/149 [11%] vs. 47/149 [32%], RR: 3.06, 95% CI: 1.8 to 5. 2, P < 0.001). CONCLUSIONS: Where clinically appropriate, anesthesiologists should consider using an intravenous propofol induction technique in children who are at high risk of experiencing perioperative respiratory adverse events. VISUAL ABSTRACT: An online visual overview is available for this article at http://links.lww.com/ALN/B725.

Effects of propofol/remifentanil-based total intravenous anesthesia versus sevoflurane-based inhalational anesthesia on the release of VEGF-C and TGF-ß and prognosis after breast cancer surgery: a prospective, randomized and controlled study.

BACKGROUND: Vascular endothelial growth factor (VEGF) and transforming growth factor-ß (TGF-ß) have been involved in tumor growth and metastasis. Sevoflurane may promote angiogenesis, whereas propofol can present an anti-angiogenic effect. In this study, we compared the effects of propofol/remifentanil-based total intravenous anesthesia (TIVA) and sevoflurane-based inhalational anesthesia on the release of VEGF-C and TGF-ß, as well as recurrence- free survival (RFS) rates in the patients undergoing breast cancer surgery. METHODS: Eighty female patients undergoing breast cancer resection were enrolled and randomized to receive either sevoflurane-based inhalational anesthesia (SEV group) or propofol/remifentanil-based TIVA (TIVA group). The serum concentrations of VEGF-C and TGF-ß before and 24 h after surgery were measured and RFS rates over a two-year follow-up were analyzed in both groups. The postoperative pain scores assessed using a visual analogue scale (VAS) and the use of perioperative opioids were also evaluated. RESULTS: Although VAS scores at 2 h and 24 h after surgery were comparable between the two groups, there were more patients receiving postoperative fentanyl in the TIVA group (16[40%]) compared with the SEV group (6[15%], p = 0.023). VEGF-C serum concentrations increased after surgery from 105 (87-193) pg/ml to174 (111-281) pg/ml in the SEV group (P = 0.009), but remained almost unchanged in the TIVA group with 134 (80-205) pg/ml vs.140(92-250) pg/ml(P = 0.402). The preoperative to postoperative change for VEGF-C of the SEV group (50 pg/ml) was significantly higher than that of the TIVA group (12 pg/ml) with a difference of 46 (- 11-113) pg/ml (P = 0.008). There were also no significant differences in the preoperative and postoperative TGF-ß concentrations between the two groups. The two-year RFS rates were 78% and 95% in the SEV and TIVA groups (P = 0.221), respectively. CONCLUSION: In comparison with sevoflurane-based inhalational anesthesia, propofol/remifentanil -based total intravenous anesthesia can effectively inhibit the release of VEGF-C induced by breast surgery, but didn't seem to be beneficial in the short-term recurrence rate of breast cancer. TRIAL REGISTRATION: Chictr.org.cn ChiCTR1800017910 . Retrospectively Registered (Date of registration: August 20, 2018).

A high risk of sleep apnea is associated with less postoperative cognitive dysfunction after intravenous anesthesia: results of an observational pilot study.

BACKGROUND: The obstructive sleep apnea syndrome (OSAS) is characterized by temporary cerebral hypoxia which can cause cognitive dysfunction. On the other hand, hypoxia induced neurocognitive deficits are detectable after general anesthesia. The objective of this study was to evaluate the impact of a high risk of OSAS on the postoperative cognitive dysfunction after intravenous anesthesia. METHODS: In this single center trial between June 2012 and June 2013 43 patients aged 55 to 80 years with an estimated hospital stay of at least 3 days undergoing surgery were enrolled. Patients were screened for a high risk of OSAS using the STOP-BANG test. The cognitive function was assessed using a neuropsychological test battery, including the DemTect test for cognitive impairment and the RMBT test for memory, the day before surgery and within 36 h after extubation. RESULTS: Twenty-two of the 43 analyzed patients were identified as patients with a high risk of OSAS. Preoperatively, OSAS patients showed a significant worse performance only for the DemTect (p = 0.0043). However, when comparing pre- and postoperative test results, the OSAS patients did not show a significant loss in any test but significantly improved in RMBT test, whereas the control group showed a significant worse performance in three of eight tests. In five tests, we found a significant difference between the two groups with respect to the change from pre- to postoperative cognitive function. CONCLUSION: Patients with a high risk of OSAS showed a less impairment of memory function and work memory performance after intravenous anesthesia. This might be explained by a beneficial effect of intrinsic hypoxic preconditioning in these patients.

Response surface modelling of the pharmacodynamic interaction between propofol and remifentanil in patients undergoing anaesthesia.

This study describes the pharmacodynamic interaction between propofol and remifentanil. Sixty patients who were scheduled for elective surgery under general anaesthesia (30 males/30 females) were enrolled. Patients were randomly allocated to receive one of 15 combinations of drug levels. Baseline electroencephalograms (EEGs) were recorded for 5 minutes prior to administering the drugs. Patients received a target-controlled infusion at one of four predefined doses of propofol (high, 3 µg/mL; medium, 1.5 µg/mL; low, 0.5 µg/mL; or no drug) and of remifentanil (high, 6 or 8 ng/mL; medium, 4 ng/mL; low, 2 ng/mL; or no drug). The occurrence of muscle rigidity, apnoea, and loss of consciousness (LOC) was monitored, and EEGs were recorded during the drug administration phase. Electroencephalographic approximate entropy (ApEn) and temporal linear mode complexity (TLMC) parameters at baseline and under steady state conditions were calculated off-line. Response surfaces were developed to map the interaction between propofol and remifentanil to the probability of occurrence for quantal responses (muscle rigidity, apnoea, LOC) and ApEn and TLMC measurements. Model parameters were estimated using non-linear mixed effects modelling. The response surface revealed infra-additive and synergistic effects for muscle rigidity and apnoea, respectively. The effects of the combined drugs on LOC and EEG parameters (eg, ApEn and TLMC) were additive. The C50 estimates of remifentanil (ng/mL) and propofol (µg/mL) were 9.11 and 130 000 for muscle rigidity, 8.99 and 6.26 for apnoea, 13.9 and 3.04 for LOC, 23.4 and 10.4 for ApEn, and 14.8 and 6.51 for TLMC, respectively. The probability of occurrence for muscle rigidity declined when propofol was combined with remifentanil.

Total intravenous anesthesia will supercede inhalational anesthesia in pediatric anesthetic practice.

Inhalational anesthesia has dominated the practice of pediatric anesthesia. However, as the introduction of agents such as propofol, short-acting opioids, midazolam, and dexmedetomidine a monumental change has occurred. With increasing use, the overwhelming advantages of total intravenous anesthesia (TIVA) have emerged and driven change in practice. These advantages, outlined in this review, will justify why TIVA will supercede inhalational anesthesia in future pediatric anesthetic practice.

Are postoperative behavioural changes after adenotonsillectomy in children influenced by the type of anaesthesia?: A randomised clinical study.

BACKGROUND: Negative postoperative behavioural changes (NPOBCs) are very frequent in children after surgery and general anaesthesia. If they persist, emotional and cognitive development may be affected significantly. OBJECTIVE: To assess whether the choice of different anaesthetic techniques for adenotonsillectomy may impact upon the incidence of NPOBC in repeated measurements. DESIGN: A randomised, controlled, parallel-group trial. SETTING: University Hospital Split, Croatia. PATIENTS: Sixty-four children (aged 6 to 12 years, ASA 1 to 2) undergoing adenotonsillectomy assigned into one of two groups: sevoflurane (S) (n = 32) or total intravenous anaesthesia (TIVA) (n = 32). INTERVENTIONS: Permuted-block randomisation with random block sizes of 4, 6 and 8, administering anaesthesia, and evaluation of NPOBC with the Post Hospitalization Behavior Questionnaire (PHBQ: 27 items describing six subscales). The PHBQ was filled out by parents at postoperative days (POD) 1, 3, 7 and 14, and 6 months after surgery. MAIN OUTCOME MEASURES: Differences in numbers of NPOBCs between two anaesthesia techniques, and NPOBC analysis by subscales. RESULTS: The prevalence of at least one NPOBC after surgery ranged from a maximum of 80% [95% confidence interval (CI) 71 to 90%] on POD 1 to a minimum of 43% (95% CI 31 to 56%) 6 months after surgery. Absolute risk reduction for at least one NPOBC in the TIVA group compared with the S group increased from 0.24 on POD 1 to 0.55 6 months after surgery. The number of NPOBCs was also lower in the TIVA group [median 5, interquartile range (IQR) 2 to 10] than in the S group (median 22, IQR 10 to 32) (P < 0.001). The overall number of NPOBCs within PHBQ subscales was significantly lower in the TIVA group than in the S group. The largest difference in the number of NPOBCs between groups was observed for the separation anxiety subscale (mean 5, 95% CI 1 to 9; P < 0.001) followed by the general anxiety subscale (mean 4, 95% CI 3 to 5; P < 0.001) and apathy/withdrawal subscale (mean 3, 95% CI 1 to 5; P < 0.001). CONCLUSION: The prevalence of NPOBC after elective adenotonsillectomy in 6 to 12-year-old children was very high (80%). The choice of anaesthetic technique for adenotonsillectomy in children influenced the incidence and type of NPOBC. Sevoflurane/nitrous oxide anaesthesia was associated with more frequent and prolonged NPOBCs than TIVA, especially in the separation anxiety, general anxiety and withdrawal/apathy subscales.

New drugs and technologies, intravenous anaesthesia is on the move (again).

Although well established in clinical practice, both propofol and midazolam have limitations. New hypnotics with different and potentially superior pharmacokinetics and pharmacodynamics are under development. These include the benzodiazepine receptor agonists CNS7056 and JM-1232 (-), the etomidate-based methoxycarbonyl-etomidate and carboetomidate, the propofol-related structures PF0713 and fospropofol, and THRX-918661/AZD3043. The basic pharmacology and the initial anaesthesia studies for each of these agents are reviewed. Several of the agents (CNS7056, THRX-918661/AZD3043, and fospropofol) have reached the stage of clinical trials. To be successful, novel compounds need to establish clear clinical advantages over existing agents and where possible the new agents are discussed in this context. Computer-controlled drug administration offers the ability to automatically implement infusion schemes too complex for manual use and the possibility of linking patient monitoring to administration to enhance patient safety.

World SIVA: the pediatric initiative.

Total intravenous anesthesia and targeted controlled infusions are emerging and developing techniques that can have a broad range of important clinical applications in future pediatric care.

TIVA, TCI, and pediatrics: where are we and where are we going?

The current role of TIVA in children is limited because of hardware limitations, and pharmacokinetic and monitoring issues. Nonetheless, the role of TIVA in children has been increasing in the past decade, in part because of surgical and medical indications. If TIVA is to become more widely used, it must be easy and simple to set up, without serious drawbacks and without added risks. Currently, many drugs destined for use with TIVA in children are off-label, and their pharmacology is poorly understood. Such off-label designations must be resolved if TIVA is to become more widely used. At the same time, many institutions have a limited number of infusion pumps, which creates a serious bottleneck and restriction on the use of TIVA.. If a true TIVA technique is used, i.v. access must be established before induction of anesthesia, which will require a means to establish i.v. access painlessly, e.g., using a topical local anesthetic. This is not a common practice in a number of jurisdictions but must be introduced if TIVA is to expand in its scope in children. Currently, I believe that we deliver a 'partial' TIVA technique in which TIVA occasionally follows an inhalational induction but in the future when the current obstacles have been resolved, I believe that we will be able practice a true TIVA technique ubiquitously in children.

Total intravenous anaesthesia techniques for ambulatory surgery.

PURPOSE OF REVIEW: The purpose of the present review is to provide an updated discussion on the use of total intravenous anaesthesia (TIVA) for ambulatory surgery, based on results from recent studies put into the context of issues already known. RECENT FINDINGS: The current use of TIVA for ambulatory surgery seems to be abundant. It is encouraged by the simplicity of the method, increased experience and declining costs with the propofol and remifentanil combination. The TIVA methods are well tolerated and perceived to give good quality patient care; with rapid, clear-headed emergence and low incidence of postoperative nausea and vomiting. Cost-efficacy and other benefits of recovery from TIVA versus alternative techniques of anaesthesia seem to depend more on the patient and the individual perioperative setting than on the TIVA concept per se. Further development of TIVA will include the refinement of target control systems, the introduction of new drugs and adjuvants and advanced equipment for automatic drug delivery, as well as improved effect monitoring. SUMMARY: TIVA is well tolerated and simple. It is associated with less postoperative nausea and vomiting than inhalational anaesthesia and has no residual paralyses as are possible with locoregional techniques. Propofol with remifentanil seems to be the dominating TIVA technique, delivered either by conventional pumps or by target control systems.

Propofol: its role in changing the practice of anesthesia.

Pharmacokinetics and pharmacodynamics of propofol infusions during general anesthesia. By Audrey Shafer, Van A. Doze, Steven L. Shafer, and Paul F. White. Anesthesiology 1988; 69:348-56. Reprinted with permission.The pharmacokinetic and pharmacodynamic properties of propofol (Diprivan) were studied in 50 elective surgical patients. Propofol was administered as a bolus dose, 2 mg/kg iv, followed by a variable-rate infusion, 0-20 mg/min, and intermittent supplemental boluses, 10-20 mg iv, as part of a general anesthetic technique that included nitrous oxide, meperidine, and muscle relaxants. For a majority of the patients (n = 30), the pharmacokinetics of propofol were best described by a two-compartment model. The propofol mean total body clearance rate was 2.09 +/- 0.65 l/min (mean +/- SD), the volume of distribution at steady state was 159 +/- 57 l, and the elimination half-life was 116 +/- 34 min. Elderly patients (patients older than 60 yr vs. those younger than 60 yr) had significantly decreased clearance rates (1.58 +/- 0.42 vs. 2.19 +/- 0.64 l/min), whereas women (vs. men) had greater clearance rates (33 +/- 8 vs. 26 +/- 7 ml x kg x min ) and volumes of distribution (2.50 +/- 0.81 vs. 2.05 +/- 0.65 l/kg). Patients undergoing major (intraabdominal) surgery had longer elimination half-life values (136 +/- 40 vs. 108 +/- 29 min). Patients required an average blood propofol concentration of 4.05 +/- 1.01 micrograms/ml for major surgery and 2.97 +/- 1.07 micrograms/ml for nonmajor surgery. Blood propofol concentrations at which 50% of patients (EC50) were awake and oriented after surgery were 1.07 and 0.95 microgram/ml, respectively. Psychomotor performance returned to baseline at blood propofol concentrations of 0.38-0.43 microgram/ml (EC50). This clinical study demonstrates the feasibility of performing pharmacokinetic and pharmacodynamic analyses when complex infusion and bolus regimens are used for administering iv anesthetics.

Total intravenous anesthesia including ketamine versus volatile gas anesthesia for combat-related operative traumatic brain injury.

BACKGROUND: Traumatic brain injury is a leading cause of death and severe neurologic disability. The effect of anesthesia techniques on neurologic outcomes in traumatic brain injury and potential benefits of total intravenous anesthesia (TIVA) compared with volatile gas anesthesia (VGA), although proposed, has not been well evaluated. The purpose of this study was to compare TIVA versus VGA in patients with combat-related traumatic brain injury. METHODS: The authors retrospectively reviewed 252 patients who had traumatic brain injury and underwent operative neurosurgical intervention. Statistical analyses, including propensity score and matched analyses, were performed to assess differences between treatment groups (TIVA vs. VGA) and good neurologic outcome. RESULTS: Two hundred fourteen patients met inclusion criteria and were analyzed; 120 received VGA and 94 received TIVA. Good neurologic outcome (Glasgow Outcome Score 4-5) and decreased mortality were associated with TIVA compared with VGA (75% vs. 54%; P = 0.002 and 5% vs. 16%; P = 0.02, respectively). Multivariate logistic regression found admission Glasgow Coma Scale score of 8 or greater (odds ratio, 13.3; P < 0.001) and TIVA use (odds ratio, 2.3; P = 0.05) to be associated with good neurologic outcomes. After controlling for confounding factors using propensity analysis and repeated one-to-one matching of patients receiving TIVA with those receiving VGA with regard to Injury Severity Score, Glasgow Coma Scale score, base deficit, Head Abbreviated Injury Score, and craniectomy or craniotomy, the authors could not find an association between treatment and neurologic outcome. CONCLUSION: Total intravenous anesthesia often including ketamine was not associated with improved neurologic outcome compared with VGA. Multiple confounders limit conclusions that can be drawn from this retrospective study.

Fast-track anesthesia with remifentanil and spinal analgesia for cardiac surgery: the effect on pain control and quality of recovery.

OBJECTIVES: To assess pain intensity and quality of postoperative recovery in patients given fast-track anesthesia and spinal analgesia versus patients treated with standard anesthesia. DESIGN: A prospective, randomized, controlled study. SETTING: A private institution. PARTICIPANTS: Eighty-three patients who underwent cardiac surgery with cardiopulmonary bypass were analyzed. INTERVENTIONS: General anesthesia consisted of remifentanil and spinal analgesia (low-dose morphine and clonidine) for the fast-track group (FTG) and sufentanil without spinal analgesia for the control group (CG). During the postoperative period, paracetamol and patient-controlled intravenous analgesia (PCA) with morphine were given. MEASUREMENTS AND MAIN RESULTS: Postoperative pain intensity was evaluated during 48 hours with visual analog scale scores and intravenous morphine consumption. Pain impact on quality of life was assessed with the brief pain inventory (BPI) score (days 1-8), and recovery was evaluated with the quality of recovery score (QoR-40, day 4). Compared with the CG, FTG pain intensity was significantly lower 0 to 4 (p < 0.01) and 6 to 12 hours (p < 0.05) after surgery, as was their cumulative intravenous PCA morphine consumption (p = 0.01). BPI scores supported that FTG patients had significantly (p < 0.01) less "pain at its worst" on days 1 and 2, their BPI-assessed pain interfered significantly less with daily life on day 1 (p < 0.001), and their global QoR-40 score (day 4) was significantly higher (p < 0.05). CONCLUSIONS: Fast-track anesthesia combined with morphine-clonidine spinal analgesia controlled postoperative pain better and obtained a better QoR than conventional analgesia.

Anaesthesia in Cancer Surgery: Can it Affect Cancer Survival?

Surgical removal of a tumor may, ironically, unleash prometastatic effects that enhance cancer recurrence and metastatic disease. The patient's physiologic response to the surgical trauma may increase tumor cell growth and invasiveness while diminishing the immune system's ability to eliminate residual disease. At the same time anaesthetic drugs used to accomplish the surgery may also have important effects on cancer cells and the immune system. Those combined effects potentially lead to sooner recurrence of local or metastatic cancer, and, ultimately, decreased survival. This review explores current research on the influences of surgery and anaesthesia on tumor cells, the immune system, and cancer recurrence. Although a substantial body of evidence sheds much light on the nature of these processes and is at times suggestive of how they might be relevant in clinical practice that literature also reveals a foundation of data that remain largely preclinical with as yet insufficient human study to support clinical recommendations. The tantalizing possibility that anaesthetic care of the surgical oncology patient might affect long term oncologic outcome remains unproven speculation, awaiting prospective human study.

New advances in anesthesia.

Pharmacologic advances in anesthesia over the last decade have focused on drug safety, shorter durations of action, reversibility, and ease of administration. This is reflective of major changes in the focus of patient care from inpatient to outpatient settings as well as from available risk management data that support the investigation of these new drugs. The pharmacologic advances discussed included those drugs in current practice as well as experimental drugs yet to be released for general clinical use. Inhaled agents, such as isoflurane and perhaps the experimental agent, desflurane, will maintain or achieve their popularity because of the relative ease of administration and wide margins of safety. Propofol, the most recent intravenous anesthetic available for clinical use, has already gained wide acceptance because of its dual function as an induction and maintenance agent and its appropriateness for use in the ambulatory surgical population. The role of midazolam in anesthesia practice has increased to such an extent that it has largely supplanted the use of diazepam (Valium). The introduction of the antagonist, flumazenil, will undoubtedly enhance the safety and efficacy of midazolam as well as broaden its applicability of use across various patient populations. Several of the newer synthetic narcotics, such as alfentanil and sufentanil, have replaced other narcotics formerly used in anesthesia practice, such as meperidine and morphine, primarily because of their short action and lack of significant side effects. The use of muscle relaxants as a critical component of anesthetic management has led to the development of a number of new drugs in this classification. Pharmacologic management of patients under anesthesia will at some future date likely include the administration of alpha 2 agonists. Administration of these drugs can reduce anesthetic requirements of traditional agents by as much as 50%. As research continues, new drugs will be incorporated into the practice of anesthesia, ones that will promote rapid uptake, low toxicity, intense analgesia, easy reversibility, shorter durations, and fewer side effects. One measure of success relative to pharmacologic development in anesthesia is the recent and dramatic decreases in patient morbidity and mortality figures over the last decade. This attests to the rapid growth and development of not only improved patient monitoring systems but also newly improved "agents of sleep."

[Clinical study on total intravenous anesthesia with droperidol, fentanyl and ketamine--20. Summary of three thousand cases and the future of this anesthetic method].

Total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK) was given to over three thousand patients during four years from April 1989 through March 1993. The patients ranged in age from three months to eighty seven years. They underwent surgical, orthopedic, gynecological, thoracic, plastic and otolaryngeal surgeries, but patients who underwent craniotomy and obstetric operations were excluded. None of them developed any serious complications primarily due to DFK. DFK has many advantages such as the broad safety margin for three agents employed in DFK, no accident by N2O, no air pollution, empty bowels, no increase in middle ear pressure etc, while this has disadvantages such as high blood pressure, slow awakening from anesthesia and unpleasant dreams. Calcium channel blockers are very effective for antagonizing high blood pressure, and rapid recovery from anesthesia can be easily obtained by reducing ketamine dose given and also by application of epidural block. Intraoperative dreams may be avoided by concomitant use of benzodiazepines. Thus we are convinced that DFK can be a good as well as convenient anesthetic method for clinical anesthesia.

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

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.