Enhanced recovery protocols for ambulatory surgery.

INTRODUCTION: In the United States, ambulatory surgeries account for up to 87% of all surgical procedures. (1) It was estimated that 19.2 million ambulatory surgeries were performed in 2018 (https://www.hcup-us.ahrq.gov/reports/statbriefs/sb287-Ambulatory-Surgery-Overview-2019.pdf). Cataract procedures and musculoskeletal surgeries are the most common surgical interventions performed in ambulatory centers. However, more complex surgical interventions, such as sleeve gastrectomies, oncological, and spine surgeries, and even arthroplasties are routinely performed as day cases or in a model of an ambulatory extended recovery. (2-5) The ambulatory surgery centers industry has grown since 2017 by 1.1% per year and reached a market size of $31.2 billion. According to the Ambulatory Surgery Center Association, there is a potential to save $57.6 billion in Medicare costs over the next decade (https://www.ibisworld.com/industry-statistics/market-size/ambulatory-surgery-centers-united-states/). These data suggest an expected rise in the volume of ambulatory (same day) or extended ambulatory (23 h) surgeries in coming years. Similar increases are also observed in other countries. For example, 75% of elective surgeries are performed as same-day surgery in the United Kingdom. (6) To reduce costs and improve the quality of care after those more complex procedures, ambulatory surgery centers have started implementing patient-centered, high-quality, value-based practices. To achieve those goals, Enhanced Recovery After Surgery (ERAS) protocols have been implemented to reduce the length of stay, decrease costs, increase patients' satisfaction, and transform clinical practices. The ERAS fundamentals for ambulatory surgery are based on five pillars, including (1) preoperative patient counseling, education, and optimization; (2) multimodal and opioid-sparing analgesia; (3) nausea and vomiting, wound infection, and venous thromboembolism prophylaxis; (4) maintenance of euvolemia; and (5) encouragement of early mobility. Those pillars rely on interdisciplinary teamwork led by anesthesiologists, surgery-specific workgroups, and safety culture. (2) Research shows that a team of ambulatory anesthesiologists is crucial in improving postoperative nausea and vomiting (PONV) and pain control. (7) This review will summarize the current evidence on the elements and clinical importance of implementing ERAS protocol for ambulatory surgery.

International Delphi Expert Consensus on Safe Return to Surgical and Endoscopic Practice: From the Coronavirus Global Surgical Collaborative.

OBJECTIVE: The aim of this work is to formulate recommendations based on global expert consensus to guide the surgical community on the safe resumption of surgical and endoscopic activities. BACKGROUND: The COVID-19 pandemic has caused marked disruptions in the delivery of surgical care worldwide. A thoughtful, structured approach to resuming surgical services is necessary as the impact of COVID-19 becomes better controlled. The Coronavirus Global Surgical Collaborative sought to formulate, through rigorous scientific methodology, consensus-based recommendations in collaboration with a multidisciplinary group of international experts and policymakers. METHODS: Recommendations were developed following a Delphi process. Domain topics were formulated and subsequently subdivided into questions pertinent to different aspects of surgical care in the COVID-19 crisis. Forty-four experts from 15 countries across 4 continents drafted statements based on the specific questions. Anonymous Delphi voting on the statements was performed in 2 rounds, as well as in a telepresence meeting. RESULTS: One hundred statements were formulated across 10 domains. The statements addressed terminology, impact on procedural services, patient/staff safety, managing a backlog of surgeries, methods to restart and sustain surgical services, education, and research. Eighty-three of the statements were approved during the first round of Delphi voting, and 11 during the second round. A final telepresence meeting and discussion yielded acceptance of 5 other statements. CONCLUSIONS: The Delphi process resulted in 99 recommendations. These consensus statements provide expert guidance, based on scientific methodology, for the safe resumption of surgical activities during the COVID-19 pandemic.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on the Role of Neuromonitoring in Perioperative Outcomes: Cerebral Near-Infrared Spectroscopy.

Some neurological complications following surgery have been related to a mismatch in cerebral oxygen supply and demand that may either lead to more subtle changes of brain function or overt complications like stroke or coma. Discovery of a perioperative neurological complication may be outside the treatment window, thereby making prevention an important focus. Early commercial devices used differential spectroscopy to measure relative changes from baseline of 2 chromophores: oxy- and deoxyhemoglobin. It was the introduction of spatially resolved spectroscopy techniques that allowed near-infrared spectroscopy (NIRS)-based cerebral oximetry as we know it today. Modern cerebral oximeters measure the hemoglobin saturation of blood in a specific "optical field" containing arterial, capillary, and venous blood, not tissue oxygenation itself. Multiple cerebral oximeters are commercially available, all of which have technical differences that make them noninterchangeable. The mechanism and meaning of these measurements are likely not widely understood by many practicing physicians. Additionally, as with many clinically used monitors, there is a lack of high-quality evidence on which clinicians can base decisions in their effort to use cerebral oximetry to reduce neurocognitive complications after surgery. Therefore, the Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together an international team of multidisciplinary experts including anesthesiologists, surgeons, and critical care physicians to objectively survey the literature on cerebral oximetry and provide consensus, evidence-based recommendations for its use in accordance with the GRading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria for evaluating biomedical literature. The group produced the following consensus recommendations: (1) interpreting perioperative cerebral oximetry measurements in the context of a preinduction baseline value; (2) interpreting perioperative cerebral oximetry measurements in the context of the physiologic variables that affect them; (3) using caution in comparing cerebral oximetry values between different manufacturers; (4) using preoperative cerebral oximetry to identify patients at increased risk of adverse outcomes after cardiac surgery; (5) using intraoperative cerebral oximetry indexed to preinduction baseline to identify patients at increased risk of adverse outcomes after cardiac surgery; (6) using cerebral oximetry to identify and guide management of acute cerebral malperfusion during cardiac surgery; (7) using an intraoperative cerebral oximetry-guided interventional algorithm to reduce intensive care unit (ICU) length of stay after cardiac surgery. Additionally, there was agreement that (8) there is insufficient evidence to recommend using intraoperative cerebral oximetry to reduce mortality or organ-specific morbidity after cardiac surgery; (9) there is insufficient evidence to recommend using intraoperative cerebral oximetry to improve outcomes after noncardiac surgery.

Pectoral block versus paravertebral block: a systematic review, meta-analysis and trial sequential analysis.

BACKGROUND: Pectoral (PECs) block was first described by Blanco et al for postoperative analgesia in breast surgery. It was proposed to be an easier and safer alternative to thoracic epidural or paravertebral block (PVB). In this systematic review and meta-analysis, we compare the perioperative analgesic efficacy and adverse events of PECs block and PVB. METHODS: We systematically searched PubMed, Central, EMBASE, CINAHL, Google Scholar, Web of Science citation index, US clinical trials register, Wanfang database, as well as recent conference abstracts, for clinical studies comparing the two techniques. Analgesic efficacy was assessed according to the time to first rescue analgesia and 24 hours opioid consumption. Adverse events from the trials were recorded and reported descriptively. RESULTS: The literature search was last updated on 20 February 2020. We identified a total of 10 randomized controlled trials (RCTs) comparing PECs to PVB with 252 and 250 patients, respectively. There was no difference in 24 hours opioid consumption between PECs and PVB. There was no significant difference in the time to rescue analgesia between the two cohorts. The most common adverse event noted was postoperative nausea and vomiting). Trial sequence analysis indicate that further studies are unlikely to alter the conclusion regarding opioid requirement. CONCLUSION: Our systematic review suggests that PECs and PVB are comparable in postoperative analgesia efficacy for mastectomy, and further studies are unlikely to alter the conclusion. The choice of technique should, therefore, be based on practitioner skill and institutional guidelines. PROSPERO REGISTRATION NUMBER: CRD42020165137.

Incidence, risk factors, and consequences of residual neuromuscular block in the United States: The prospective, observational, multicenter RECITE-US study.

STUDY OBJECTIVE: To determine the incidence burden and associated risk factors of residual neuromuscular block (rNMB) during routine U.S. hospital care. DESIGN: Blinded multicenter cohort study. SETTING: Operating and recovery rooms of ten community and academic U.S. hospitals. PATIENTS: Two-hundred fifty-five adults, ASA PS 1-3, underwent elective abdominal surgery with general anesthesia and ≥1 dose of non-depolarizing neuromuscular blocking agent (NMBA) for endotracheal intubation and/or maintenance of NMB between August 2012 and April 2013. INTERVENTIONS: TOF measurements using acceleromyography were performed on patients already receiving routine anesthetic care for elective open or laparoscopic abdominal surgery. Measurements allowed assessment of the presence of residual neuromuscular block (rNMB), defined as a train-of-four (TOF) ratio <0.9 at tracheal extubation. We recorded patient and procedural characteristics and assessed TOF ratios (T4/T1) at various times throughout the procedure and at tracheal extubation. Differences in patient and clinical characteristics were compared using Fisher's exact test for categorical variables and t-test for continuous variables. Multivariate logistic regression assessed risk factors associated with rNMB at extubation. MAIN RESULTS: Most of the study population, 64.7% (n = 165) had rNMB (TOF ratio < 0.9), among them, 31.0% with TOF ratio <0.6. Among those receiving neostigmine and/or qualitative peripheral nerve stimulation per clinical decision, 65.0% had rNMB. After controlling for confounders, we observed male gender (odds ratio: 2.60, P = 0.008), higher BMI (odds ratio: 1.04/unit, P = 0.043), and surgery at a community hospital (odds ratio: 3.15, P = 0.006) to be independently associated with increased odds of rNMB. CONCLUSIONS: Assessing TOF ratios blinded to the care team, we found that the majority of patients (64.7%) in this study had rNMB at tracheal extubation, despite neostigmine administration and qualitative peripheral nerve stimulation used for routine clinical care. Qualitative neuromuscular monitoring and clinical judgement often fails to detect rNMB after neostigmine reversal with potential severe consequences to the patient. Our data suggests that clinical care could be improved by considering quantitative neuromuscular monitoring for routine care.

Neurologic and cognitive outcomes associated with the clinical use of xenon: a systematic review and meta-analysis of randomized-controlled trials.

BACKGROUND: Xenon has been shown to have positive neurologic effects in various pre-clinical models. This study systematically reviewed the randomized-controlled trials (RCTs) investigating neurologic and cognitive outcomes associated with the clinical use of xenon. METHODS: We searched PubMed, CENTRAL, EMBASE, CINAHL, elibrary.ru (for Russian studies), Google Scholar (for Russian studies), and Wanfang (for Chinese studies) for appropriate RCTs comparing neurologic or cognitive outcomes after clinical use of xenon with control treatment or with other anesthetic agents. RESULTS: Seventeen RCTs met the inclusion criteria. Two studies investigated the effects of xenon plus therapeutic hypothermia to treat neonatal asphyxia or out-of-hospital cardiac arrest. Compared with therapeutic hypothermia alone, xenon and therapeutic hypothermia reduced cerebral white matter abnormalities after cardiac arrest but had no effect on neurocognitive outcome and mortality. Xenon had no added value when used to treat neonatal asphyxia. Thirteen RCTs compared neurocognitive effects of xenon with other anesthetic agents in surgical patients. While xenon may be associated with improved short-term (< three hours) cognitive outcome, no medium-term (six hours to three months) advantage was observed, and longer-term data are lacking. No differences in biochemical (S-100ß, neuron-specific enolase) and neuropsychologic (attentional performance) outcomes were found with xenon compared with other anesthetic drugs. Finally, two studies suggest that brief, intermittent administration of sub-anesthetic doses of xenon to patients during the acute phase of substance withdrawal may improve neurocognitive outcomes. CONCLUSIONS: Despite promising pre-clinical results, the evidence for positive clinical neurologic and cognitive outcomes associated with xenon administration is modest. Nevertheless, there is some evidence to suggest that xenon may be associated with better neurologic outcomes compared with the standard of care therapy in certain specific clinical situations. More clinical trials are needed to determine any potential benefit linked to xenon administration.

Correction to: American Society for Enhanced Recovery (ASER) and Perioperative Quality Initiative (POQI) joint consensus statement on perioperative fluid management within an enhanced recovery pathway for colorectal surgery.

[This corrects the article DOI: 10.1186/s13741-016-0049-9.].

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Gastrointestinal Dysfunction Within an Enhanced Recovery Pathway for Elective Colorectal Surgery.

The primary driver of length of stay after bowel surgery, particularly colorectal surgery, is the time to return of gastrointestinal (GI) function. Traditionally, delayed GI recovery was thought to be a routine and unavoidable consequence of surgery, but this has been shown to be false in the modern era owing to the proliferation of enhanced recovery protocols. However, impaired GI function is still common after colorectal surgery, and the current literature is ambiguous with regard to the definition of postoperative GI dysfunction (POGD), or what is typically referred to as ileus. This persistent ambiguity has impeded the ability to ascertain the true incidence of the condition and study it properly within a research setting. Furthermore, a rational and standardized approach to prevention and treatment of POGD is needed. The second Perioperative Quality Initiative brought together a group of international experts to review the published literature and provide consensus recommendations on this important topic with the goal to (1) develop a rational definition for POGD that can serve as a framework for clinical and research efforts; (2) critically review the evidence behind current prevention strategies and provide consensus recommendations; and (3) develop rational treatment strategies that take into account the wide spectrum of impaired GI function in the postoperative period.

American Society for Enhanced Recovery (ASER) and Perioperative Quality Initiative (POQI) joint consensus statement on perioperative fluid management within an enhanced recovery pathway for colorectal surgery.

BACKGROUND: Enhanced recovery may be viewed as a comprehensive approach to improving meaningful outcomes in patients undergoing major surgery. Evidence to support enhanced recovery pathways (ERPs) is strong in patients undergoing colorectal surgery. There is some controversy about the adoption of specific elements in enhanced recovery "bundles" because the relative importance of different components of ERPs is hard to discern (a consequence of multiple simultaneous changes in clinical practice when ERPs are initiated). There is evidence that specific approaches to fluid management are better than alternatives in patients undergoing colorectal surgery; however, several specific questions remain. METHODS: In the "Perioperative Quality Initiative (POQI) Fluids" workgroup, we developed a framework broadly applicable to the perioperative management of intravenous fluid therapy in patients undergoing elective colorectal surgery within an ERP. DISCUSSION: We discussed aspects of ERPs that impact fluid management and made recommendations or suggestions on topics such as bowel preparation; preoperative oral hydration; intraoperative fluid therapy with and without devices for goal-directed fluid therapy; and type of fluid.

Xenon Anesthesia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Xenon anesthesia has been studied for decades. However, no meta-analysis of randomized controlled trials (RCTs) on xenon anesthesia has been conducted. The aim of this study was to systematically review all available evidence from RCTs comparing xenon and other inhaled and IV anesthetics on anesthetic outcomes. Our meta-analysis attempted to quantify the effects of xenon anesthesia on clinical outcomes in relation to other anesthetics. METHODS: We found 43 RCTs from PubMed, MEDLINE, CENTRAL, EMBASE, and CINAHL (until January 2015). A total of 31 studies comparing xenon (841 patients) with other inhaled agents (836 patients) and 12 studies comparing xenon (373 patients) with propofol (360 patients) were found. We evaluated clinical outcomes, such as intraoperative hemodynamics, emergence, and postoperative nausea and vomiting (PONV). RESULTS: Patients undergoing xenon anesthesia had a lower heart rate and higher mean arterial pressure (MAP) intraoperatively than those receiving volatile anesthesia (mean difference = -6 min⁻¹ [99% confidence interval {99% CI} -10.0 to -2.3]; mean difference = 9 mm Hg [99% CI 3.1-14.4]) and propofol anesthesia (mean difference = -10 min⁻¹ [99% CI -12.4 to -6.6]; mean difference = 7 mm Hg [99% CI 0.85-13.2]). Compared with baseline, intraoperative MAP remained relatively stable (change < 5.5%, 99% CI within ±20% of the baseline) under xenon anesthesia, but MAP decreased by ≥15% under volatile (mean difference = -17 mm Hg [99% CI -29.5 to - 4.9], percentage change = -17.5%) and propofol (mean difference = -14 mm Hg [99% CI -26.1 to -2.5], percentage change = -15.0%) anesthesia. Patients had faster emergence from xenon than from volatile anesthesia: eyes opening (versus all volatile agents: mean 4 vs 7 minutes, percentage change = -49.8% [99% CI -55.1% to -44.0%]), tracheal extubation (versus all volatile agents: mean 4 vs 8 minutes percentage change = -44.6% [99% CI -57.3% to -28.1%]), orientation (versus sevoflurane: mean 5 vs 10 minutes, percentage change = -45.1% [99% CI -58.5% to -28.1%]), countdown (versus sevoflurane: mean 6 vs 10 minutes, percentage change = -41.7% [99% CI -50.3% to -31.6%]; versus isoflurane: mean 6 vs 14 minutes, percentage change = -57.7% [99% CI -65.7% to -48.3%]), and reaction on demand (versus sevoflurane: mean 4 vs 8 minutes, percentage change = -53.2% [99% CI -65.7% to -35.6%]). However, xenon anesthesia increased the risks of PONV (incidence 34.4% vs 19.9%; risk ratio = 1.72 [99% CI 1.10-2.69], risk difference = 0.19 [99% CI 0.04-0.33]). CONCLUSIONS: Xenon anesthesia provides relatively more stable intraoperative blood pressure, lower heart rate, and faster emergence from anesthesia than volatile and propofol anesthesia. However, xenon is associated with a higher incidence of PONV.

Demonstrating Value: A Case Study of Enhanced Recovery.

An enhanced recovery after surgery strategy will be increasingly adopted in the era of value-based care. The various elements in each enhanced recovery after surgery protocol are likely to add value to the overall patient surgical journey. Although the evidence varies considerably based on type of surgery and patient group, the team-based approach of care should be universally applied to patient care. This article provides an overview of up-to-date techniques and methodology for enhanced recovery, including an overview of value-based care, delivery, and the evidence base supporting enhanced recovery after surgery.

Paravertebral Block for Inguinal Herniorrhaphy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Paravertebral block (PVB) is a safe and effective anesthetic technique for thoracotomy and mastectomy. However, no systematic review or meta-analysis has focused on PVB for inguinal herniorrhaphy. Our study compares PVB with general anesthesia/systemic analgesia, neuraxial blocks, and other peripheral nerve blocks. METHODS: We analyzed 14 randomized controlled trials from PubMed, MEDLINE, CENTRAL, EMBASE, and CINAHL up to February 2015, without language restriction, comparing PVB under sedation with general anesthesia/systematic analgesia (135 vs 133 patients), neuraxial blocks (191 vs 186 patients), and other peripheral nerve blocks (119 vs 117 patients). We investigated pain scores, consumption of postoperative analgesia, incidence of postoperative nausea and vomiting (PONV), length of hospital stay, postanesthesia care unit bypassing rate, time to perform blocks, intraoperative hemodynamics, and incidence of urinary retention. Joint hypothesis testing was adopted for pain and analgesics, PONV, and hemodynamic variables. All analyses were performed with RevMan 5.2.11 (Cochrane Collaboration, Copenhagen). Hartung-Knapp-Sidik-Jonkman method was used for post hoc testing. RESULTS: PVB reduced PONV (nausea: risk ratio [RR] = 0.22; 95% confidence interval [CI], 0.05-0.93; numbers needed to treat [NNT] = 4.5; I = 15% and vomiting: RR = 0.15; 95% CI, 0.03-0.76; NNT = 8.3; I = 0%) compared with general anesthesia/systematic analgesia (quality of evidence [QoE]: high). Compared with neuraxial blocks, PVB resulted in less postoperative nausea (RR = 0.34 [95% CI, 0.13-0.91], NNT = 8.3, I = 0%) and urinary retention (RR = 0.14 [95% CI, 0.05-0.42], NNT = 7.4, I = 0%) than neuraxial blocks (QoE: high). More time was needed to perform PVB than neuraxial blocks (standardized mean difference = 1.90 [95% CI, 0.02-3.77], I = 92%; mean difference = 5.33 minutes; QoE: moderate). However, the available data could not reject the null hypothesis of noninferiority on all pain scores and analgesic requirements for both PVB versus general anesthesia/systematic analgesia and PVB versus neuraxial blocks (QoE: low), as well as on hemodynamic outcomes for PVB versus neuraxial blocks (QoE: moderate). Our systematic review showed that PVB decreased postoperative pain scores and analgesic requirement as compared with ilioinguinal block and transversus abdominis plane block. CONCLUSIONS: This meta-analysis shows that PVB provides an anesthesia with fewer undesirable effects for inguinal herniorrhaphy. The choice between general anesthesia/systematic analgesia, neuraxial blocks, PVB, and other peripheral nerve blocks should be based on time available to perform the block and a complete coverage over the relevant structures by the blocks.

[Indications and limitations for colloids in interventions and surgery]. / Indikationen und Limitationen für Kolloide bei Intervention und Operation.

BACKGROUND: Over the last few decades colloids have played an important part in the stabilisation of patients with acute need of intravascular volume replacement. After the 6S and the CHEST trials were published in 2012 and the subsequent recommendations of the European Medicines Agency (EMA) and the Food and Drug Administration (FDA) there has been some uncertainty about the current clinical relevance and routine use of colloids. OBJECTIVES: This article summarizes the current evidence and relevance of colloids in the perioperative environment and in the interventional setting on the basis of the recently published German S3-guidelines for volume therapy in adults. RESULTS: In situations of acute volume resuscitation colloids are still appropriate. Only colloids in balanced solutions should be used. Possible side effects, contraindications and the maximum daily dose have to be taken into consideration when administering colloids.

Lidocaine patch for acute pain management: a meta-analysis of prospective controlled trials.

BACKGROUND: Local anesthetic is one of the cornerstones of multimodal analgesia. We investigated the efficacy of the lidocaine patch for acute pain management. METHODS: We searched MEDLINE, CINAHL, Scopus, and the Cochrane Controlled Trials Register for published prospective controlled clinical trials that evaluated the analgesic effect of the lidocaine patch for acute or postoperative pain management (1966--2014). The outcomes were postoperative opioid consumption, pain intensity and length of hospital stay. RESULTS: Five trials comparing the lidocaine patch with control (no treatment/placebo) for acute or postoperative pain treatment/management were included in this meta-analysis. Data was analyzed on 251 patients. Between the lidocaine patch group and the control group, no significant difference was found for all three outcomes (all p > 0.05). For postoperative opioid consumption, mean difference (MD) was -8.2 mg morphine equivalent (95% CI -28.68, 12.24). For postoperative pain intensity, MD was -9.1 mm visual analog scale or equivalent (95% CI -23.31, 5.20). For length of hospital stay, MD was -0.2 days (95% CI -0.80, 0.43). CONCLUSION: Application of a lidocaine patch may not be an effective adjunct for acute and postoperative pain management, in terms of pain intensity, opioid consumption and length of hospital stay. LIMITATIONS: The limitations were a small number of included studies, potential biases from some unblinded studies, clinical heterogeneity between studies, and incomplete reported data for adjunct analgesics.

Sufentanil sublingual tablet system for the management of postoperative pain following open abdominal surgery: a randomized, placebo-controlled study.

BACKGROUND AND OBJECTIVES: This study evaluates the efficacy and safety of a sufentanil sublingual tablet system (SSTS) for the management of postoperative pain following open abdominal surgery. METHODS: At 13 hospital sites in the United States, patients following surgery with pain intensity of greater than 4 on an 11-point numerical rating scale were randomized to receive SSTS dispensing a 15-µg sufentanil tablet sublingually with a 20-minute lockout or an identical system dispensing a placebo tablet sublingually. Pain intensity scores were recorded at baseline and for up to 72 hours after starting study drug. The primary end point was time-weighted summed pain intensity difference (SPID) over 48 hours. Secondary end points included SPID and total pain relief (TOTPAR) for up to 72 hours and patient and health care provider global assessments of the method of pain control. RESULTS: Summed pain intensity difference over 48 hours was significantly higher in the SSTS group than in the placebo group (least squares mean [SEM], 105.60 [10.14] vs 55.58 [13.11]; P = 0.001). Mean SPID and TOTPAR scores were significantly higher in the SSTS group at all time points from 1 hour (SPID) or 2 hours (TOTPAR) until 72 hours (P < 0.05). In the SSTS group, patient global assessment and health care provider global assessment ratings of good or excellent were greater than placebo at all time points (P < 0.01). Safety parameters, including adverse events and vital signs, were similar for SSTS and placebo. CONCLUSIONS: These results suggest that SSTS is effective and safe for the management of postoperative pain in patients following open abdominal surgery.

Inter-device differences in monitoring for goal-directed fluid therapy.

PURPOSE: Goal-directed fluid therapy is an integral component of many Enhanced Recovery After Surgery (ERAS) protocols currently in use. The perioperative clinician is faced with a myriad of devices promising to deliver relevant physiologic data to better guide fluid therapy. The goal of this review is to provide concise information to enable the clinician to make an informed decision when choosing a device to guide goal-directed fluid therapy. PRINCIPAL FINDINGS: The focus of many devices used for advanced hemodynamic monitoring is on providing measurements of cardiac output, while other, more recent, devices include estimates of fluid responsiveness based on dynamic indices that better predict an individual's response to a fluid bolus. Currently available technologies include the pulmonary artery catheter, esophageal Doppler, arterial waveform analysis, photoplethysmography, venous oxygen saturation, as well as bioimpedance and bioreactance. The underlying mechanistic principles for each device are presented as well as their performance in clinical trials relevant for goal-directed therapy in ERAS. CONCLUSIONS: The ERAS protocols typically involve a multipronged regimen to facilitate early recovery after surgery. Optimizing perioperative fluid therapy is a key component of these efforts. While no technology is without limitations, the majority of the currently available literature suggests esophageal Doppler and arterial waveform analysis to be the most desirable choices to guide fluid administration. Their performance is dependent, in part, on the interpretation of dynamic changes resulting from intrathoracic pressure fluctuations encountered during mechanical ventilation. Evolving practice patterns, such as low tidal volume ventilation as well as the necessity to guide fluid therapy in spontaneously breathing patients, will require further investigation.