THE concept of preemptive analgesia to reduce the magnitude and duration of postoperative pain was paved in 1983 by Woolf, who showed evidence for a central component of postinjury pain hypersensitivity in experimental studies. Subsequently, an overwhelming amount of experimental data demonstrated that various antinociceptive techniques applied before injury were more effective in reducing the postinjury central sensitization phenomena as compared with administration after injury. Finally, these promising experimental findings were taken into clinical testing of the hypothesis. Although early reviews of clinical findings were mostly negative, there is still a widespread belief of the efficacy of preemptive analgesia among clinicians. The definition of preemptive analgesia has varied, thereby causing confusion and misunderstanding of the concept. Because the original observations in experimental studies suggested that timing of analgesic treatment was important to obtain efficient reduction of postinjury pain hypersensitivity phenomena, we performed an updated review of studies to compare the role of timing of analgesia i.e., preoperative versus intraoperative or postoperative initiation of analgesia. In this review we are not considering studies designed to compare preemptive analgesia versus no treatment. We have only included double-blind, randomized, controlled trials of identical or very similar analgesic regimens, where the only difference between study groups was timing of analgesia.

A qualitative and quantitative systematic review of preemptive analgesia for postoperative pain relief: the role of timing of analgesia

RESULTS The pooled risk of all serious infections was 11.8% (95% CI, 7.0%-16.7%) in the restrictive group and 16.9% (95% CI, 8.9%-25.4%) in the liberal group. The risk ratio (RR) for the association between transfusion strategies and serious infection was 0.82 (95% CI, 0.72-0.95) with little heterogeneity (I 2 = 0%; τ 2 <.0001). The number needed to treat (NNT) with restrictive strategies to prevent serious infection was 38 (95% CI, 24-122). The risk of infection remained reduced with a restrictive strategy, even with leukocyte reduction (RR, 0.80 [95% CI, 0.67-0.95]). For trials with a restrictive hemoglobin threshold of <7.0 g/dL, the RR was 0.82 (95% CI, 0.70-0.97) with NNT of 20 (95% CI, 12-133). With stratification by patient type, the RR was 0.70 (95% CI, 0.54-0.91) in patients undergoing orthopedic surgery and 0.51 (95% CI, 0.28-0.95) in patients presenting with sepsis. There were no significant differences in the incidence of infection by RBC threshold for patients with cardiac disease, the critically ill, those with acute upper gastrointestinal bleeding, or for infants with low birth weight. CONCLUSIONS AND RELEVANCE Among hospitalized patients, a restrictive RBC transfusion strategy was associated with a reduced risk of health care–associated infection compared with a liberal transfusion strategy. Implementing restrictive strategies may have the potential to lower the incidence of health care–associated infection.

https://jamanetwork.com/journals/jama/articlepdf/1853162/joi140035.pdf

Health Care–Associated Infection After Red Blood Cell Transfusion: A Systematic Review and Meta-analysis

BACKGROUND: Improving perioperative efficiency and throughput has become increasingly important in the modern practice of anesthesiology. Fast-track surgery represents a multidisciplinary approach to improving perioperative efficiency by facilitating recovery after both minor (i.e., outpatient) and major (inpatient) surgery procedures. In this article we focus on the expanding role of the anesthesiologist in fast-track surgery. METHODS: A multidisciplinary group of clinical investigators met at McGill University in the Fall of 2005 to discuss current anesthetic and surgical practices directed at improving the postoperative recovery process. A subgroup of the attendees at this conference was assigned the task of reviewing the peer-reviewed literature on this topic as it related to the role of the anesthesiologist as a perioperative physician. RESULTS: Anesthesiologists as perioperative physicians play a key role in fast-track surgery through their choice of preoperative medication, anesthetics and techniques, use of prophylactic drugs to minimize side effects (e.g., pain, nausea and vomiting, dizziness), as well as the administration of adjunctive drugs to maintain major organ system function during and after surgery. CONCLUSION: The decisions of the anesthesiologist as a key perioperative physician are of critical importance to the surgical care team in developing a successful fast-track surgery program. (Anesth Analg 2007;104:1380‐96)

http://ether.stanford.edu/asc1/documents/fast2.pdf

The role of the anesthesiologist in fast-track surgery: From multimodal analgesia to perioperative medical care

Introduction:Massive transfusion (MT) protocols have been shown to improve survival in severely injured patients. However, others have noted that these higher fresh frozen plasma (FFP):red blood cell (RBC) ratios are associated with increased risk of organ failure. The purpose of this study was to d

/pdf/predefined-massive-transfusion-protocols-are-associated-with-4naefnh6ef.pdf

Predefined massive transfusion protocols are associated with a reduction in organ failure and postinjury complications.

In this systematic review we focused on postoperative recovery and complications using four different anesthetic techniques. The database MEDLINE was searched via PubMed (1966 to June 2002) using the search words “anesthesia” and with ambulatory surgical procedures limited to randomized controlled t

Comparison of recovery profile after ambulatory anesthesia with propofol, isoflurane, sevoflurane and desflurane: a systematic review.

BACKGROUND\nImmunosuppression is a consequence of allogeneic (homologous) blood transfusion (ABT) in humans and is associated with an increased risk in cancer recurrence rates after potentially curative surgery as well as an increase in the frequency of postoperative bacterial infections. Although a meta-analysis has been reported demonstrating the relationship between ABT and colon cancer recurrence, no meta-analysis has been reported demonstrating the relationship of ABT to postoperative bacterial infection.\n\n\nMETHODS\nTwenty peer-reviewed articles published from 1986 to 2000 were included in a meta-analysis. Criteria for inclusion included a clearly defined control group (nontransfused) compared with a treated (transfused) group and statistical analysis of accumulated data that included stepwise multivariate logistic regression analysis. In addition, a subgroup of publications that included only the traumatically injured patient was included in a separate meta-analysis. A fixed effects analysis was conducted with odds ratios obtained by using the conditional maximum likelihood method and 95% confidence intervals on the obtained odds ratios were determined using the mid-p technique.\n\n\nRESULTS\nThe total number of subjects included in this meta-analysis was 13,152 (5,215 in the transfused group and 7,937 in the nontransfused group). The common odds ratio for all articles included in this meta-analysis evaluating the association of ABT to the incidence of postoperative bacterial infection was 3.45 (range, 1.43-15.15), with 17 of the 20 studies demonstrating a value of p < or = 0.05. These results provide overwhelming evidence that ABT is associated with a significantly increased risk of postoperative bacterial infection in the surgical patient. The common odds ratio of the subgroup of trauma patients was 5.263 (range, 5.03-5.43), with all studies showing a value of p < 0.05 (0.005-0.0001). These results demonstrate that ABT is associated with a greater risk of postoperative bacterial infection in the trauma patient when compared with those patients receiving ABT during or after elective surgery.\n\n\nCONCLUSION\nThese results demonstrate that ABT is an associated and apparently significant and frequently overlooked risk factor for the development of postoperative bacterial infection in the surgical patient. Allogeneic blood transfusion is a greater risk factor in the traumatically injured patient when compared with the elective surgical patient for the development of postoperative bacterial infection.

Allogeneic Blood Transfusion Increases the Risk of Postoperative Bacterial Infection: A Meta-Analysis: [2002][A-423]

IMPLICATIONS: In this study, although 41%-94% of the patients were fast-track eligible after laparoscopic surgery, only 35%-53% of the patients actually bypassed the postanesthesia care unit (PACU) because of anesthetic-related factors and surgical complications. Residual sedation was the most common anesthetic-related cause of failure to bypass thePACU.

Fast-tracking after outpatient laparoscopy: reasons for failure after propofol, sevoflurane, and desflurane anesthesia.

Caudal Epidural Anesthesia in Conscious Premature and High-Risk Infants

Intraocular pressure (IOP) measurements in children are usually performed under nitrous oxide and halothane anesthesia. We studied the effects of both time and end-tidal halothane concentration on IOP in 80 children (mean age +/- SD = 4.5 +/- 2.9 yr), to determine the most optimal time to make such measurements in anesthetized children. In 30 children the end-tidal halothane and nitrous oxide concentrations were kept constant while IOP was measured at 1-min intervals after the induction of anesthesia. Intraocular pressure did not change with time. In another 50 children IOP was measured immediately after induction, after 10 min of steady-state end-tidal halothane concentrations of both 0.5% and 1.0% in 66% nitrous oxide, and immediately after tracheal intubation. Intraocular pressure did not differ significantly at either halothane concentration but increased after tracheal intubation. We conclude that in patients anesthetized with halothane and nitrous oxide, IOP after induction remains constant over time and is not affected by end-tidal halothane concentrations up to 1.0% but is affected by tracheal intubation. Thus, the optimal time to measure IOP in children receiving up to 1% halothane in 66% nitrous oxide is during the first 10 min after induction, but before tracheal intubation.

John E. Forestner

Papers

Allogeneic Blood Transfusion Increases the Risk of Postoperative Bacterial Infection: A Meta-Analysis: [2002][A-423]

Fast-tracking after outpatient laparoscopy: reasons for failure after propofol, sevoflurane, and desflurane anesthesia.

Caudal Epidural Anesthesia in Conscious Premature and High-Risk Infants

Effects of halothane on intraocular pressure in anesthetized children

Caudal Epidural Anesthesia Reduces Blood Loss During Hypospadias Repair