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Conditions created by the COVID-19 pandemic have impacted many aspects of medical practice. Responding to this crisis has required health systems to rapidly address a multitude of concerns, including workforce safety, staff redeployment, supply shortages and physical space restructuring. The pace of change created by new information and evolving conditions has proven challenging for traditionally-structured academic departments in medicine. Pandemic medicine requires a nimbleness in decisionmaking, clarity of communication and comprehensiveness of services that may demand a temporary rearrangement of leadership structure and clinical service delivery. Furthermore, the uncertain nature of a pandemic may require reinstitution and dissolution of services as demand sporadically either rises or falls. As the global medical community continues to respond to what may be multiple COVID-19 peaks stretching over months or years, it is important that approaches to preparation and management of the pandemic are shared to enable the identification of best practices and an effective response. With the availability of open access and free communication technologies, these strategies can be easily shared among the global anaesthesia community. The approach outlined here represents one way to organise leadership and streamline communication in order to reinvent an academic department to match the dynamic requirements of crisis conditions. We describe our experience in offering new services such as an airway team, COVID-19 simulation training and personal protective equipment testing, as well as our approach to evaluating the rapid flow of research findings related to SARS-CoV-2 and COVID-19. We summarise lessons learnt and our adaptation to what may be a "new normal" in anaesthesiology practice. [ABSTRACT FROM AUTHOR]

Objective: This study reports on the efficacy of using the anesthesia simulator to teach sedation and analgesia to nurses. This provision of sedation and analgesia to a patient is accomplished with the goal of maintaining the ability of the patient to respond purposefully to auditory or tactile stimuli.Methods: Nurses working in areas of the hospital where conscious sedation is performed were the participants in this sedation and analgesia training course. Prior to the training session, the participants read the American Society of Anesthesiology Practice guidelines for sedation and analgesia by non-anesthesiologists. At the time of the training session, each participant completed a written pretest, had an introduction to sedation and analgesia with four clinical crisis teaching scenarios using the anesthesia simulator, a practical exam using the simulator, and a written post-test. Each participant was also given the opportunity to complete an evaluation of the session.Results: Twenty nurses completed the training session. The written tests had a maximum possible score of 30. Mean score on the written pretest was 22.9 +/- 3.54, and mean score on the written post-test was 26.0 +/- 4.24 (p < 0.001). Seventeen of the twenty subjects scored higher on the post-test. Mean practical exam score was 5.5 of a possible 6.0. Mean participant rating of the education session was 3.75 (1 = poor, 4 = excellent). All but one participant rated the length of the training session as "about right."Conclusions: The anesthesia simulator provides an excellent tool for teaching conscious sedation skills to hospital nurses. The participants' test performance improved following the session, and they also rated the educational experience as excellent. [ABSTRACT FROM AUTHOR]

Background: Although the Modified Observer's Assessment of Alertness and Sedation (MOAA/S) is frequently used in sedation-related drug and device studies, a major shortcoming is that it does not differentiate between lighter and deeper levels of general anaesthesia because the only noxious stimulus of the MOAA/S is a trapezius squeeze. The primary aim of this investigation was to expand the MOAA/S score to include truly noxious stimulation, thereby extending the dynamic range of the assessment to include sedation states consistent with deeper levels of general anaesthesia., Methods: Twenty healthy volunteers received target controlled infusions of fentanyl (target=0.8 ng ml(-1)) and propofol (starting at 0.5 µg ml(-1) and gradually increasing to 5 µg ml(-1)). At each propofol concentration, a MOAA/S score was obtained before and after tetanic electrical stimulation. The tetanic electrical stimulation current was gradually increased until the subject responded or until 50 mA was delivered without a response. A pharmacodynamic model was constructed to characterize the concentration-effect relationship between propofol and the MOAA/S scores., Results: All subjects required a significantly higher propofol concentration to produce unresponsiveness to tetanic electrical stimulation at 50 mA compared with a standardized trapezius squeeze. The pharmacodynamic model adequately characterized the concentration-effect relationship., Conclusions: The Extended Observer's Assessment of Alertness and Sedation (or EOAA/S) extends the range of the widely used MOAA/S score to include truly noxious stimulation, thereby enabling the identification of drug-induced central nervous system depression representative of surgical anaesthesia., (© The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Although remifentanil's short-acting pharmacokinetic profile makes it well suited for procedures during which a brief period of intense analgesia is required, setting up an infusion pump for brief procedures is inconvenient. The clinical pharmacology of remifentanil administered by bolus injection, a more convenient alternative, has not been explored in detail. The primary aim of this study was to examine the safety of single bolus doses of remifentanil in conscious, healthy, adult volunteers breathing room air. Secondary aims included the evaluation of remifentanil pharmacokinetics and analgesic effects after bolus injection and a comparison of these issues in younger vs older adults., Methods: Using a randomized, double-blind, placebo-controlled, dose-escalation, crossover study design, 64 subjects (16 over 60 years old) received remifentanil or placebo by bolus injection in a fixed unit dose separated by a 1 h washout period. Respiratory effects were assessed using a respiratory intervention scale. Analgesic effects were assessed using pressure algometry. A population pharmacokinetic model was constructed using non-linear, mixed-effects modelling techniques based on arterial blood samples. Computer simulations were performed to illustrate the clinical application of the pharmacokinetic model., Results: Dose-related increases in both respiratory and analgesic effects were observed. In general, the respiratory depression observed was mild and easily treated with requests to breathe or the administration of oxygen, although the older cohort (and some younger subjects) experienced more substantial respiratory depression at lower doses. The pharmacokinetics of bolus-dose remifentanil were adequately described by a two-compartment model. The pharmacokinetic simulations illustrated the potential utility of bolus-dose remifentanil., Conclusions: Bolus injection could potentially be a safe and effective means of administering remifentanil in clinical situations requiring a brief period of intense analgesia. Because some subjects, both old and young, experienced significant respiratory depression even at low doses, careful monitoring of respiratory function is essential.

Remifentanil is still in its infancy in terms of postmarketing development. Its appropriate role in modern anesthesia care is still being defined and reports of novel clinical applications for remifentanil are frequently appearing in the anesthesia literature. This review will focus on selected advances in our understanding of remifentanil pharmacokinetics and pharmacodynamics and on newly proposed clinical applications for remifentanil.

Purpose: To illustrate the clinical utility of a short acting opioid (remifentanil) based general anesthetic for Cesarean section in a parturient with compromised cardiac function., Clinical Features: A 23-yr-old primigravida, complicated by a recurrent aortic coarctation with an approximate 50% narrowing of the aortic arch, presented for elective Cesarean section at 37 wk gestational age. Initially asymptomatic, her clinical condition had deteriorated as the pregnancy progressed, with worsening episodes of mild chest pain and shortness of breath. A semi-elective Cesarean section under general anesthesia was planned at 37 wk to minimize the potential for aortic complications associated with the hemodynamic stress of labour. Remifentanil was infused at 0.05 to 0.1 microg x kg(-1) x min(-1) with good sedation and analgesia for the placement of invasive monitors. The infusion was increased to 0.2 microg x kg(-1) x min(-1) for induction, and combined with isoflurane 0.4 to 0.6% for maintenance of anesthesia. The patient maintained stable hemodynamics throughout and her trachea was extubated without difficulty at the end of the procedure. The newborn did not require tracheal intubation, mask ventilation or naloxone and was in excellent condition upon transfer to the well baby nursery., Conclusion: Remifentanil, when used as part of an opioid-based general anesthetic for Cesarean section, can provide maternal hemodynamic stability with minimal neonatal respiratory depression and should allow for immediate postoperative tracheal extubation of the mother.

Background: It is common clinical practice to administer reduced doses of opioid to patients suffering from hemorrhagic shock to minimize adverse hemodynamic consequences and to prevent prolonged opioid effect However, the scientific foundation supporting this practice is not well established. The aim of this study was to test the hypothesis that hemorrhagic shock alters both the distribution and clearance of opioids using fentanyl in a porcine isobaric hemorrhage model., Methods: Eighteen pigs were randomized to shock or control groups. The animals in the shock group were subjected to hemorrhage using an isobaric method. Pigs in both groups received fentanyl (50 microg/kg) intravenously over 5 min. Frequent arterial blood samples were obtained for radioimmunoassay. Each animal's pharmacokinetic parameters were estimated by fitting a three-compartment model to the concentration versus time data Nonlinear mixed-effects population pharmacokinetic models examining the influence of mean arterial pressure and cardiac index were also constructed. Clinical simulations using the final population model were performed., Results: The shock cohort reached substantially higher fentanyl concentrations. The shock group's central clearance and central- and second-compartment distribution volumes were significantly reduced. The most useful population model scaled all pharmacokinetic parameters to mean arterial pressure. The simulations illustrated that hemorrhagic shock results in higher fentanyl concentrations for any given dosage scheme., Conclusion: The essential finding of the study is that fentanyl pharmacokinetics are substantially altered by hemorrhagic shock. The reduced opioid requirement commonly observed during hemorrhagic shock is at least partially attributable to pharmacokinetic mechanisms.

Introduction: Remifentanil is a new, short-acting, rapidly metabolized opioid. Because remifentanil is metabolized in blood and tissues by nonspecific esterases, there is a substantial difference between arterial and venous remifentanil concentrations. This difference may greatly affect the estimation of pharmacokinetic and pharmacodynamic parameters., Objectives: To assess the effects of sampling site on the pharmacokinetic and pharmacodynamic characteristics of remifentanil., Methods: Ten healthy female subjects received intravenous remifentanil at an infusion rate of 3 microg/kg/min for 10 minutes. Serial blood samples were collected during and after drug administration from the radial artery and antecubital vein. A spectral edge measure was derived from the processed electroencephalographic and used as a measure of opioid effect., Results: Venous concentrations were lower than arterial concentrations during the infusion of remifentanil. Pharmacokinetic parameters estimated from venous and arterial data differed significantly. When arterial concentrations were plotted against electroencephalographic effect, a classic counterclockwise hysteresis loop was observed, indicating a time-lag between changes in concentration and changes in effect. However, concentrations from venous blood produced a clockwise hysteresis loop that would classically suggest the development of acute tolerance., Conclusions: If this study had been conducted with venous samples alone, inappropriate conclusions such as acute tolerance could have been inferred. When designing studies to measure the acute time course (ie, non-steady state) of concentration and effect, the potential effects of sampling site on pharmacokinetic and pharmacodynamic characteristics must be carefully considered, particularly when the arteriovenous drug concentration difference is large.

Background: Remifentanil is a short-acting opioid whose pharmacokinetics have been characterized in detail. However, the impact of obesity on remifentanil pharmacokinetics has not been specifically examined. The goal of this study was to investigate the influence of body weight on remifentanil pharmacokinetics., Methods: Twelve obese and 12 matched lean subjects undergoing elective surgery received a 1-min remifentanil infusion after induction of anesthesia. Arterial blood samples were collected for determination of remifentanil blood concentrations. Each subject's pharmacokinetic parameters were estimated by fitting a two-compartment model to the concentration versus time curves. Nonlinear mixed-effects population models examining the influence of lean body mass (LBM) and total body weight (TBW) were also constructed. Clinical simulations using the final population model were performed., Results: The obese patient cohort reached substantially higher remifentanil concentrations. The individual pharmacokinetic parameters of a two-compartment model were not significantly different between the obese versus lean cohorts (unless normalized to TBW). The final population model scaled central clearance and the central and peripheral distribution volumes to LBM. The simulations illustrated that remifentanil pharmacokinetics are not grossly different in obese versus lean subjects and that TBW based dosing in obese patients can result in excessively high remifentanil concentrations., Conclusions: The essential findings of the study are that remifentanil's pharmacokinetics are not appreciably different in obese versus lean subjects and that remifentanil pharmacokinetic parameters are therefore more closely related to LBM than to TBW. Clinically this means that remifentanil dosing regimens should be based on ideal body weight (or LBM) and not TBW.

We present a case in which remifentanil infusion was used to provide analgesia during epidural catheter placement in a parturient who was experiencing great difficulty staying motionless because of extremely painful uterine contractions. Remifentanil may provide certain advantages in this setting, including improved analgesia during the procedure, briefer residual maternal and fetal (or newborn) drug effects after the procedure, and greater technical ease of catheter placement because of decreased movement induced by pain. Pharmacokinetic simulation of the dose administered suggests that analgesic effect-site concentrations can be rapidly produced, and that these concentrations decline rapidly to clinically insignificant levels after the infusion.

Background: The pharmacokinetics of a single dose (15 microg/kg) of oral transmucosal fentanyl citrate (OTFC) have been characterized. A range of doses may eventually be used in clinical practice. The goal of this study was to determine if the pharmacokinetics of OTFC are dose proportional for doses ranging from 200 to 1,600 microg., Methods: Twelve healthy male volunteers were studied on four different occasions, receiving 200, 400, 800, and 1,600 microg OTFC in a double-blind, randomized protocol. Venous blood samples were collected at selected times during and after dosing for a 24-h period and assayed for fentanyl using a radioimmunoassay. Maximum concentration, time to maximum concentration, area under the curve, and elimination half-life were determined for each dose administered. In addition, respiratory rate, need for verbal prompting to breathe, and supplemental oxygen requirements were noted., Results: Mean fentanyl concentration time curves were similarly shaped with increasing doses. Both peak concentrations and area under the curve increased linearly with an increase in dose, whereas time to reach peak serum concentrations did not vary significantly between doses. Except for the 200-microg dose, the apparent elimination half-life remained relatively constant (358-386 min). The incidence of low respiratory rate, supplemental oxygen requirement, and number of breathing prompts significantly increased with increasing doses., Conclusions: Oral transmucosal fentanyl citrate exhibits dose-proportional pharmacokinetics over the dose range of 200-1,600 microg.

Background: Remifentanil is an esterase-metabolized opioid with a rapid clearance. The aim of this study was to contrast the pharmacokinetics and pharmacodynamics of remifentanil and alfentanil in healthy, adult male volunteers., Methods: Ten volunteers received infusions of remifentanil and alfentanil on separate study sessions using a randomized, open-label crossover design. Arterial blood samples were analyzed to determine drug blood concentrations. The electroencephalogram was employed as the measure of drug effect. The pharmacokinetics were characterized using a moment analysis, a nonlinear mixed effects model (NONMEM) population analysis, and context-sensitive half-time computer simulations. After processing the raw electroencephalogram to obtain the spectral edge parameter, the pharmacodynamics were characterized using an effect compartment, inhibitory maximum effect model., Results: Pharmacokinetically, the two drugs are similar in terms of steady-state distribution volume (VD(SS)), but remifentanil's central clearance (CLc)) is substantially greater. The NONMEM analysis population pharmacokinetic parameters for remifentanil include a CLc of 2.9 l x min(-1), a VDss of 21.81, and a terminal half-life of 35.1 min. Corresponding NONMEM parameters for alfentanil are 0.36 l x min(-1), 34.11, and 94.5 min. Pharmacodynamically, the drugs are similar in terms of the time required for equilibration between blood and the effect-site concentrations, as evidenced by a T(12)k(e0) for remifentanil of 0.75 min [corrected] and 0.96 min for alfentanil. However, remifentanil is 19 times more potent than alfentanil, with an effective concentration for 50% maximal effect of 19.9 ng x ml(-1) versus 375.9 ng x ml(-1) for alfentanil., Conclusions: Compared to alfentanil, the high clearance of remifentanil, combined with its small steady-state distribution volume, results in a rapid decline in blood concentration after termination of an infusion. With the exception of remifentanil's nearly 20-times greater potency (30-times if alfentanil partitioning between whole blood and plasma is considered), the drugs are pharmacodynamically similar.

The purpose of this study was to model pharmacodynamically the reversal of midazolam sedation with flumazenil. Ten human volunteers underwent four different sessions. In session 1, individual midazolam pharmacokinetics and electroencephalographic pharmacodynamics were determined. In sessions 2 and 3, a computer-controlled infusion of midazolam with individual volunteer pharmacokinetic data was administered, targeting a plasma concentration corresponding to a light or deep level of sedation (20% or 80% of the maximal midazolam electroencephalographic effect) for a period of 210 minutes. After obtaining a stable electroencephalographic effect and constant midazolam plasma concentrations, a zero-order infusion of flumazenil was started until complete reversal of midazolam electroencephalographic effect was obtained. The flumazenil infusion was then stopped and the volunteer was allowed to resedate because of the constant midazolam drug effect. The electroencephalographic response was measured during a 180-minute period and analyzed by aperiodic analysis and fast-Fourier transforms. In session 4, a midazolam plasma concentration corresponding to a deep level of sedation was targeted for 210 minutes to examine for the possible development of acute tolerance. No flumazenil was given in session 4. For a light sedation level, with a mean midazolam plasma concentration of 160 +/- 64 ng/ml, the mean half-life of the equilibration rate constant of flumazenil reversal is 5.0 +/- 2.5 minutes, and the mean effect site concentration causing 50% of Emax is 13.7 +/- 5.8 ng/ml. For a deep level of sedation, with a mean midazolam plasma concentration of 551 +/- 196 ng/ml, the mean half-life of the equilibration rate constant is 3.9 +/- 1.5 minutes, and the mean effect site concentration causing 50% of Emax is 20.6 +/- 6.8 ng/ml. This study provides an estimate of the magnitude of the blood/central nervous system equilibration delay for flumazenil antagonism of midazolam sedation and further defines the usefulness of the electroencephalogram as a measure of midazolam pharmacodynamic effect.

Remifentanil is a novel, short-acting mu-receptor opioid agonist currently in the late stages of development. A member of the 4-anilidopiperidine class, it is unique among the currently marketed agents because of its ester structure. Remifentanil undergoes widespread extrahepatic metabolism by blood and tissue nonspecific esterases, resulting in an extremely rapid clearance of approximately 3 L/min (180 L/h). Like the other members of this class of drugs, remifentanil is lipophilic and is widely distributed in body tissues with a steady-state volume of distribution of approximately 30L. Because of its unique metabolic pathway (among this group of drugs) and rapid clearance, remifentanil represents a new pharmacokinetic class of opioid. Unlike the other fentanyl congeners, termination of the therapeutic effect of remifentanil mostly depends on metabolic clearance rather than on redistribution. The context-sensitive half-time [defined as the time necessary to achieve a 50% decrease in blood (or plasma) concentration after termination of a variable-length, continuous infusion targeted to maintain a steady-state concentration, where the 'context' is the duration of the infusion] is strikingly short for remifentanil, and this is perhaps the most compelling evidence of the pharmacokinetic singularity of the drug. Determined by computer simulation, the context-sensitive half-time of remifentanil is approximately 3 minutes, and is independent of infusion duration. Pharmacodynamically, remifentanil is similar to the other fentanyl congeners. The drug produces physiological changes consistent with potent mu-receptor agonist activity, including analgesia and sedation. Its adverse effect profile (like that of the other drugs of this class) includes ventilatory depression, nausea, vomiting, muscular rigidity, bradycardia and pruritus. Because it does not release histamine upon injection, remifentanil has fewer haemodynamic adverse effects than morphine. The therapeutic potency of remifentanil is somewhat less than that of fentanyl, with an effective concentration (producing 50% of maximal effect, as measured by electroencephalography) of approximately 15 to 20 micrograms/L. Speed of onset of effect is very rapid and is similar to that of alfentanil, which is reflected in a t1/2ke0 (a parameter used to characterise the delay between peak blood drug concentration and peak pharmacodynamic effect utilising a theoretical effect compartment) of approximately 1 to 2 minutes. Remifentanil is likely to be a welcome addition to the anaesthesia drug formulary. Anaesthetists have long recognised the need for a short-acting opioid with a predictable pharmacokinetic profile.(ABSTRACT TRUNCATED AT 400 WORDS)

The safety, pharmacokinetics, and pharmacodynamics of the investigational partial opioid agonist, mirfentanil, were determined in a dose-escalating, Phase 1 study in healthy male volunteers. Hemodynamic, central nervous system, and respiratory monitoring were used for safety assessment. The electroencephalogram (EEG) was evaluated as a surrogate measure of drug effect. Butorphanol was chosen as the control drug. In the mirfentanil group (n = 8) the dose was increased in sequential subjects from 25 micrograms.kg-1.min-1 for 30 min to 450 micrograms.kg-1.min-1 for 15 min, and in the butorphanol group (n = 10) from 2 micrograms.kg-1.min-1 for 30 min to 25 micrograms.kg-1.min-1 for 15 min. In the mirfentanil group, serious side effects were observed at plasma concentrations more than 2000 ng/mL: heart rates exceeded 130 bpm (n = 2), epileptiform EEG potentials (n = 2), and a convulsion (n = 1). The clearance of mirfentanil was high (5.8-7.2 L/min), and the volume of distribution large (247-348 L). The EEG of the subjects receiving mirfentanil showed no changes typical for opioids. Butorphanol however, caused intermittent slowing in the delta and theta ranges. The results of our study define the upper limit of safe plasma concentrations in future mirfentanil studies.

Background: Remifentanil (GI87084B) is a new short-acting opioid with a unique ester structure. Metabolism of remifentanil by ester hydrolysis results in very rapid elimination. The aim of this study was to characterize in detail the pharmacokinetic profile of remifentanil in healthy male volunteers., Methods: Ten healthy adult male volunteers received a zero-order infusion of remifentanil at doses ranging from 1 to 8 micrograms.kg-1.min-1 for 20 min. Frequent arterial blood samples were drawn and analyzed by gas chromatographic mass spectroscopy to determine the remifentanil blood concentrations. The raw pharmacokinetic data were analyzed using three different parametric compartmental modeling methods (traditional two-stage, naive pooled data, and NONMEM). The raw pharmacokinetic data also were analyzed using numeric deconvolution and a nonparametric moment technique. A computer simulation using hte pharmacokinetic parameters of the NONMEM compartmental model was performed to provide a more intuitively meaningful and clinically relevant description of the pharmacokinetics. The simulation estimated the time necessary to achieve a 50% decrease in remifentanil concentration after a variable-length infusion., Results: For each parametric method, a three-compartment mamillary model that accurately describes remifentanil's concentration decay curve was constructed. The NONMEM analysis population pharmacokinetic parameters included a central clearance of 2.8 l/min, a volume of distribution at steady state of 32.8 l, and a terminal half-life of 48 min. The mean results of the nonparametric moment analysis included a clearance of 2.9 l/min, a volume of distribution at steady state of 31.8 l, and a mean residence time of 10.9 min. The computer simulation revealed the strikingly unique pharmacokinetic profile of remifentanil compared to that of the currently available fentanyl family of opioids., Conclusions: Remifentanil is a new, short-acting opioid with promising clinical potential in anesthesiology.

Tracheal intubation by direct laryngoscopy is an essential skill for physicians working in the operating room, emergency room or intensive care unit settings. While tracheal intubation can usually be accomplished with ease by direct laryngoscopy, it is sometimes difficult or impossible because of coexisting disease or abnormal physical features. When recognized before attempts at tracheal intubation, virtually all difficult airways can be secured by the selected use of specialized tracheal intubation techniques, although many of these methods require special training, experience, assistance and equipment. When a difficult airway is unrecognized before attempts at intubation the results can be catastrophic because the personnel and equipment necessary for utilizing the specialized tracheal intubation techniques may not be immediately available and the patient's spontaneous respiratory efforts may have been eliminated by anesthetics or muscle relaxants. Thus, identifying patients who are likely to harbor an airway that cannot reliably be secured by simple direct laryngoscopy is an important skill for all acute or critical care physicians. There is an extensive research data base describing historical information, physical examination findings and radiographic features that are associated with the difficult airway. Reviewed collectively, one of the most important underlying concepts suggested by this body of research literature is that the difficult airway is a product of many anatomic and pathologic variables. A surprisingly wide variety of historical, physical examination and radiographic features associated with difficult direct laryngoscopy have been described. A rational approach to airway assessment, therefore, naturally includes a detailed history, a careful physical examination and inspection of relevant x-rays whenever time permits. As outlined in Table 5, there are specific questions to address that may warn the physician about possible airway difficulty. A number of airway assessment schemes based on physical examination findings have been proposed and tested. These schemes vary in their complexity and their clinical convenience. The simpler schemes fail to address the multifactorial nature of the problem, while the more complex systems are clinically impractical. Schemes combining the distance of the thyromental space and the visibility of the oropharyngeal structures, such as that proposed by Frerk, are perhaps the most practical and reliable of the methods proposed to date. Clearly, no one scheme is ideal. At present, preintubation airway evaluation remains a poorly quantified gestalt estimate of the chances for difficulty based on a complex juxtaposition of historical information and physical findings.(ABSTRACT TRUNCATED AT 400 WORDS)

Perioperative smoking causes acute changes in cardiopulmonary function that can have unfavorable implications for patients undergoing anesthesia. These cardiopulmonary effects are carbon monoxide and nicotine mediated changes in oxygen (O2) delivery and myocardial O2 balance. Smokers also are at increased risk for postoperative pulmonary complications that are secondary to chronic changes in lung function. Smoking-induced acute changes in cardiopulmonary function can be largely avoided by a brief period of preoperative smoking abstinence. Bringing about a decrease in postoperative pulmonary complications requires a much longer period of preoperative abstinence. Because the perioperative period is in many ways an ideal time to abandon the smoking habit permanently, anesthesiologists, in cooperation with other health professionals, can perhaps play a more active role in facilitating this process.

An athletic young male presented with right calf pain following a twisting injury during a soccer game. Other than apparently severe calf pain, no symptoms or signs of compartment syndrome were noted. The patient later returned with lateral and anterior compartment syndrome, and suffered partial loss of peroneal nerve and muscle function despite fasciotomy. Although rare, acute compartment syndrome resulting from seemingly minor injury or exertion has been reported. Pain out of proportion to the apparent injury and a history of chronic leg pain with exertion may be helpful in identifying these patients prior to development of more obvious signs and symptoms. The diagnosis of acute compartment syndrome may be confirmed by compartmental pressure measurement. Prompt intervention is indicated once the diagnosis is established.