2023 American Society of Anesthesiologists Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade: A Report by the American Society of Anesthesiologists Task Force on Neuromuscular Blockade.

These practice guidelines provide evidence-based recommendations on the management of neuromuscular monitoring and antagonism of neuromuscular blocking agents during and after general anesthesia. The guidance focuses primarily on the type and site of monitoring and the process of antagonizing neuromuscular blockade to reduce residual neuromuscular blockade.

A Beautiful Friendship-and a Lesson about Friends and Colleagues: A Classic Partnership Revisited.

David Warner, M.D., and Michael Todd, M.D., first met in 1985. They began working together at the University of Iowa (Iowa City, Iowa) a year later with a shared interest in both laboratory and clinical neuroscience-and in the operative care of neurosurgical patients. That collaboration has now lasted for 35 yr, resulting in more than 70 joint publications. More importantly, they have had the privilege of working together with close to 1,000 colleagues from around the world, in a dozen medical specialties. Their careers are an example of what can be accomplished by friendship, mutual commitment, persistence, and a willingness to join with others.

The Evolution, Current Value, and Future of the American Society of Anesthesiologists Physical Status Classification System.

The American Society of Anesthesiologists (ASA) Physical Status classification system celebrates its 80th anniversary in 2021. Its simplicity represents its greatest strength as well as a limitation in a world of comprehensive multisystem tools. It was developed for statistical purposes and not as a surgical risk predictor. However, since it correlates well with multiple outcomes, it is widely used-appropriately or not-for risk prediction and many other purposes. It is timely to review the history and development of the system. The authors describe the controversies surrounding the ASA Physical Status classification, including the problems of interrater reliability and its limitations as a risk predictor. Last, the authors reflect on the current status and potential future of the ASA Physical Status system.

Consensus Statement on Perioperative Use of Neuromuscular Monitoring.

A panel of clinician scientists with expertise in neuromuscular blockade (NMB) monitoring was convened with a charge to prepare a consensus statement on indications for and proper use of such monitors. The aims of this article are to: (a) provide the rationale and scientific basis for the use of quantitative NMB monitoring; (b) offer a set of recommendations for quantitative NMB monitoring standards; (c) specify educational goals; and (d) propose training recommendations to ensure proper neuromuscular monitoring and management. The panel believes that whenever a neuromuscular blocker is administered, neuromuscular function must be monitored by observing the evoked muscular response to peripheral nerve stimulation. Ideally, this should be done at the hand muscles (not the facial muscles) with a quantitative (objective) monitor. Objective monitoring (documentation of train-of-four ratio ≥0.90) is the only method of assuring that satisfactory recovery of neuromuscular function has taken place. The panel also recommends that subjective evaluation of the responses to train-of-four stimulation (when using a peripheral nerve stimulator) or clinical tests of recovery from NMB (such as the 5-second head lift) should be abandoned in favor of objective monitoring. During an interim period for establishing these recommendations, if only a peripheral nerve stimulator is available, its use should be mandatory in any patient receiving a neuromuscular blocking drug. The panel acknowledges that publishing this statement per se will not result in its spontaneous acceptance, adherence to its recommendations, or change in routine practice. Implementation of objective monitoring will likely require professional societies and anesthesia department leadership to champion its use to change anesthesia practitioner behavior.

Neuromonitoring in the ambulatory anesthesia setting: a pro-con discussion.

PURPOSE OF REVIEW: Various neurologically focused monitoring modalities such as processed electroencephalography (pEEG), tissue/brain oxygenation monitors (SbO2), and even somatosensory evoked responses have been suggested as having the potential to improve the well tolerated and effective delivery of care in the setting of outpatient surgery. The present article will discuss the pros and cons of such monitors in this environment. RECENT FINDINGS: There is a paucity of evidence from rigorous, well designed clinical trials demonstrating that the routine use of any neuromonitoring technique in an ambulatory surgery setting leads to meaningful cost savings or a reduction in morbidity or mortality. SUMMARY: The use of advanced neuromonitoring techniques (primarily pEEG) may be considered reasonable in two instances: for the prevention of intraoperative awareness during the administration of total intravenous anesthesia coupled with the use of a neuromuscular blocking drug, and for the prevention of relative drug overdose (and possibly postoperative delirium) in the elderly.

Electrocorticographic delineation of human auditory cortical fields based on effects of propofol anesthesia.

The functional organization of human auditory cortex remains incompletely characterized. While the posteromedial two thirds of Heschl's gyrus (HG) is generally considered to be part of core auditory cortex, additional subdivisions of HG remain speculative. To further delineate the hierarchical organization of human auditory cortex, we investigated regional heterogeneity in the modulation of auditory cortical responses under varying depths of anesthesia induced by propofol. Non-invasive studies have shown that propofol differentially affects auditory cortical activity, with a greater impact on non-core areas. Subjects were neurosurgical patients undergoing removal of intracranial electrodes placed to identify epileptic foci. Stimuli were 50Hz click trains, presented continuously during an awake baseline period, and subsequently, while propofol infusion was incrementally titrated to induce general anesthesia. Electrocorticographic recordings were made with depth electrodes implanted in HG and subdural grid electrodes implanted over superior temporal gyrus (STG). Depth of anesthesia was monitored using spectral entropy. Averaged evoked potentials (AEPs), frequency-following responses (FFRs) and high gamma (70-150Hz) event-related band power were used to characterize auditory cortical activity. Based on the changes in AEPs and FFRs during the induction of anesthesia, posteromedial HG could be divided into two subdivisions. In the most posteromedial aspect of the gyrus, the earliest AEP deflections were preserved and FFRs increased during induction. In contrast, the remainder of the posteromedial HG exhibited attenuation of both the AEP and the FFR. The anterolateral HG exhibited weaker activation characterized by broad, low-voltage AEPs and the absence of FFRs. Lateral STG exhibited limited activation by click trains, and FFRs there diminished during induction. Sustained high gamma activity was attenuated in the most posteromedial portion of HG, and was absent in all other regions. These differential patterns of auditory cortical activity during the induction of anesthesia may serve as useful physiological markers for field delineation. In this study, the posteromedial HG could be parcellated into at least two subdivisions. Preservation of the earliest AEP deflections and FFRs in the posteromedial HG likely reflects the persistence of feedforward synaptic activity generated by inputs from subcortical auditory pathways, including the medial geniculate nucleus.

Prolonged Operative Time to Extubation Is Not a Useful Metric for Comparing the Performance of Individual Anesthesia Providers.

BACKGROUND: One anesthesiologist performance metric is the incidence of "prolonged" (15 min or longer after dressing complete) times to extubation. The authors used several methods to identify the performance outliers and assess whether targeting these outliers for reduction could improve operating room workflow. METHODS: Time to extubation data were retrieved for 27,757 anesthetics and 81 faculty anesthesiologists. Provider-specific incidences of prolonged extubation were assessed by using unadjusted frequentist statistics and a Bayesian model adjusted for prone positioning, American Society of Anesthesiologist's base units, and case duration. RESULTS: 20.31% of extubations were "prolonged," and 40% of anesthesiologists were identified as outliers using a frequentist approach, that is, incidence greater than upper 95% CI (20.71%). With an adjusted Bayesian model, only one anesthesiologist was deemed an outlier. If an average anesthesiologist performed all extubations, the incidence of prolonged extubations would change negligibly (to 20.67%). If the anesthesiologist with the highest incidence of prolonged extubations was replaced with an average anesthesiologist, the change was also negligible (20.01%). Variability among anesthesiologists in the incidence of prolonged extubations was significantly less than among other providers. CONCLUSIONS: Bayesian methodology with covariate adjustment is better suited to performance monitoring than an unadjusted, nonhierarchical frequentist approach because it is less likely to identify individuals spuriously as outliers. Targeting outliers in an effort to alter operating room activities is unlikely to have an operational impact (although monitoring may serve other purposes). If change is deemed necessary, it must be made by improving the average behavior of everyone and by focusing on anesthesia providers rather than on faculty.

First-Attempt Intubation Success of Video Laryngoscopy in Patients with Anticipated Difficult Direct Laryngoscopy: A Multicenter Randomized Controlled Trial Comparing the C-MAC D-Blade Versus the GlideScope in a Mixed Provider and Diverse Patient Population.

BACKGROUND: Intubation success in patients with predicted difficult airways is improved by video laryngoscopy. In particular, acute-angle video laryngoscopes are now frequently chosen for endotracheal intubation in these patients. However, there is no evidence concerning whether different acute-angle video laryngoscopes can be used interchangeably in this scenario and would allow endotracheal intubation with the same success rate. We therefore tested whether first-attempt intubation success is similar when using a newly introduced acute-angle blade, that is an element of an extended airway management system (C-MAC D-Blade) compared with a well-established acute-angle video laryngoscope (GlideScope). METHODS: In this large multicentered prospective randomized controlled noninferiority trial, patients requiring general anesthesia for elective surgery and presenting with clinical predictors of difficult laryngoscopy were randomly assigned to intubation using either the C-MAC D-Blade or the GlideScope video laryngoscope. The hypothesis was that first-attempt intubation success using the new device (D-Blade) is no >4% less than the established device (GlideScope), which would determine noninferiority of the new instrument versus the established instrument. The secondary outcomes we observed included intubation success with multiple attempts and airway-related complications within 7 days of enrollment. RESULTS: Eleven hundred patients were randomly assigned to either video laryngoscope. Intubation success rate on first attempt was 96.2% in the GlideScope group and 93.4% in the C-MAC D-Blade group. Although the absolute difference between the 2 groups was only 2.8%, the 90.35% upper confidence limit of the difference exceeded the predefined margin (4.98%), indicating a rejection of the noninferiority hypothesis for first-attempt intubation success. For attending anesthesiologists, and upon multiple attempts, intubation success did not differ between systems. Pharyngeal injury was noted in 1% of the patients, and the incidence did not differ between interventional groups. CONCLUSIONS: Head-to-head comparison in this large multicenter trial revealed that the newly introduced C-MAC D-Blade does not yield the same first-attempt intubation success as the GlideScope in patients with predicted difficult laryngoscopy except in the hands of attending anesthesiologists. Additional research would be necessary to identify potential causes for this difference. Intubation success rates were very high with both systems, indicating that acute-angle video laryngoscopy is an exceptionally successful strategy for the initial approach to endotracheal intubation in patients with predicted difficult laryngoscopy.

The influence of the type and design of the anesthesia record on ASA physical status scores in surgical patients: paper records vs. electronic anesthesia records.

BACKGROUND: The American Society of Anesthesiologists Physical Status classification (ASA PS) of surgical patients is a standard element of the preoperative assessment. In early 2013, the Department of Anesthesia was notified that the distribution of ASA PS scores for sampled patients at the University of Iowa had recently begun to deviate from national comparison data. This change appeared to coincide with the transition from paper records to a new electronic Anesthesia Information Management System (AIMS). We hypothesized that the design of the AIMS was unintentionally influencing how providers assigned ASA PS values. METHODS: Primary analyses were based on 12-month blocks of data from paper records and AIMS. For the purpose of analysis, ASA PS was dichotomized to ASA PS 1 and 2 vs. ASA PS >2. To ensure that changes in ASA PS were not due to "real" changes in our patient mix, we examined other relevant covariates (e.g. age, weight, case distribution across surgical services, emergency vs. elective surgeries etc.). RESULTS: There was a 6.1 % (95 % CI: 5.1-7.1 %) absolute increase in the fraction of ASA PS 1&2 classifications after the transition from paper (54.9 %) to AIMS (61.0 %); p < 0.001. The AIMS was then modified to make ASA PS entry clearer (e.g. clearly highlighting ASA PS on the main anesthesia record). Following the modifications, the AS PS 1&2 fraction decreased by 7.7 % (95 % CI: 6.78-8.76 %) compared to the initial AIMS records (from 61.0 to 53.3 %); p < 0.001. There were no significant or meaningful differences in basic patient characteristics and case distribution during this time. CONCLUSION: The transition from paper to electronic AIMS resulted in an unintended but significant shift in recorded ASA PS scores. Subsequent design changes within the AIMS resulted in resetting of the ASA PS distributions to previous values. These observations highlight the importance of how user interface and cognitive demands introduced by a computational system can impact the recording of important clinical data in the medical record.

Assessing and Comparing Anesthesiologists' Performance on Mandated Metrics Using a Bayesian Approach.

BACKGROUND: Periodic assessment of performance by anesthesiologists is required by The Joint Commission Ongoing Professional Performance Evaluation program. METHODS: The metrics used in this study were the (1) measurement of blood pressure and (2) oxygen saturation (SpO2) either before or less than 5 min after anesthesia induction. Noncompliance was defined as no measurement within this time interval. The authors assessed the frequency of noncompliance using information from 63,913 cases drawn from the anesthesia information management system. To adjust for differences in patient and procedural characteristics, 135 preoperative variables were analyzed with decision trees. The retained covariate for the blood pressure metric was patient's age and, for SpO2 metric, was American Society of Anesthesiologist's physical status, whether the patient was coming from an intensive care unit, and whether induction occurred within 5 min of the start of the scheduled workday. A Bayesian hierarchical model, designed to identify anesthesiologists as "performance outliers," after adjustment for covariates, was developed and was compared with frequentist methods. RESULTS: The global incidences of noncompliance (with frequentist 95% CI) were 5.35% (5.17 to 5.53%) for blood pressure and 1.22% (1.14 to 1.30%) for SpO2 metrics. By using unadjusted rates and frequentist statistics, it was found that up to 43% of anesthesiologists would be deemed noncompliant for the blood pressure metric and 70% of anesthesiologists for the SpO2 metric. By using Bayesian analyses with covariate adjustment, only 2.44% (1.28 to 3.60%) and 0.00% of the anesthesiologists would be deemed "noncompliant" for blood pressure and SpO2, respectively. CONCLUSION: Bayesian hierarchical multivariate methodology with covariate adjustment is better suited to faculty monitoring than the nonhierarchical frequentist approach.

Intubation Biomechanics: Laryngoscope Force and Cervical Spine Motion during Intubation in Cadavers-Cadavers versus Patients, the Effect of Repeated Intubations, and the Effect of Type II Odontoid Fracture on C1-C2 Motion.

BACKGROUND: The aims of this study are to characterize (1) the cadaver intubation biomechanics, including the effect of repeated intubations, and (2) the relation between intubation force and the motion of an injured cervical segment. METHODS: Fourteen cadavers were serially intubated using force-sensing Macintosh and Airtraq laryngoscopes in random order, with simultaneous cervical spine motion recorded with lateral fluoroscopy. Motion of the C1-C2 segment was measured in the intact and injured state (type II odontoid fracture). Injured C1-C2 motion was proportionately corrected for changes in intubation forces that occurred with repeated intubations. RESULTS: Cadaver intubation biomechanics were comparable with those of patients in all parameters other than C2-C5 extension. In cadavers, intubation force (set 2/set 1 force ratio = 0.61; 95% CI, 0.46 to 0.81; P = 0.002) and Oc-C5 extension (set 2 - set 1 difference = -6.1 degrees; 95% CI, -11.4 to -0.9; P = 0.025) decreased with repeated intubations. In cadavers, C1-C2 extension did not differ (1) between intact and injured states; or (2) in the injured state, between laryngoscopes (with and without force correction). With force correction, in the injured state, C1-C2 subluxation was greater with the Airtraq (mean difference 2.8 mm; 95% CI, 0.7 to 4.9 mm; P = 0.004). CONCLUSIONS: With limitations, cadavers may be clinically relevant models of intubation biomechanics and cervical spine motion. In the setting of a type II odontoid fracture, C1-C2 motion during intubation with either the Macintosh or the Airtraq does not appear to greatly exceed physiologic values or to have a high likelihood of hyperextension or direct cord compression.

Intubation biomechanics: laryngoscope force and cervical spine motion during intubation with Macintosh and Airtraq laryngoscopes.

INTRODUCTION: Laryngoscopy and endotracheal intubation in the presence of cervical spine instability may put patients at risk of cervical cord injury. Nevertheless, the biomechanics of intubation (cervical spine motion as a function of applied force) have not been characterized. This study characterized and compared the relationship between laryngoscope force and cervical spine motion using two laryngoscopes hypothesized to differ in force. METHODS: Fourteen adults undergoing elective surgery were intubated twice (Macintosh, Airtraq). During each intubation, laryngoscope force, cervical spine motion, and glottic view were recorded. Force and motion were referenced to a preintubation baseline (stage 1) and were characterized at three stages: stage 2 (laryngoscope introduction); stage 3 (best glottic view); and stage 4 (endotracheal tube in trachea). RESULTS: Maximal force and motion occurred at stage 3 and differed between the Macintosh and Airtraq: (1) force: 48.8 ± 15.8 versus 10.4 ± 2.8 N, respectively, P = 0.0001; (2) occiput-C5 extension: 29.5 ± 8.5 versus 19.1 ± 8.7 degrees, respectively, P = 0.0023. Between stages 2 and 3, the motion/force ratio differed between Macintosh and Airtraq: 0.5 ± 0.2 versus 2.0 ± 1.4 degrees/N, respectively; P = 0.0006. DISCUSSION: The relationship between laryngoscope force and cervical spine motion is: (1) nonlinear and (2) differs between laryngoscopes. Differences between laryngoscopes in motion/force relationships are likely due to: (1) laryngoscope-specific cervical extension needed for intubation, (2) laryngoscope-specific airway displacement/deformation needed for intubation, and (3) cervical spine and airway tissue viscoelastic properties. Cervical spine motion during endotracheal intubation is not directly proportional to force. Low-force laryngoscopes cannot be assumed to result in proportionally low cervical spine motion.

The implementation of quantitative electromyographic neuromuscular monitoring in an academic anesthesia department.

BACKGROUND: Although experts agree on the importance of quantitative neuromuscular blockade monitoring, particularly for managing reversal, such monitoring is not in widespread use. We describe the processes and results of our departmental experience with the introduction of such quantitative monitoring. METHODS: In mid-2010, the senior authors became concerned about the management of nondepolarizing neuromuscular blockers (NMB) by providers within the department, based on personal observations and on a review of a departmental quality assurance/adverse event database. This review indicated the occurrence of 2 to 4 reintubations/year in the postanesthesia care unit (PACU) that were deemed to be probably or possibly related to inadequate reversal. In response, quantitative blockade equipment (Datex-Omeda ElectroSensor™ EMG system) was installed in all our main operating rooms in January 2011. This introduction was accompanied by an extensive educational effort. Adoption of the system was slow; by mid-2011, the quantitative system was being used in <50% of cases involving nondepolarizing relaxants and adverse NMB-related events continued to occur. Therefore, starting in August 2011 and extending over the next 2 years, we performed a series of 5 separate sampling surveys in the PACU in which train-of-four (TOF) ratios were recorded in 409 tracheally extubated adult patients who had received nondepolarizing NMB (almost exclusively rocuronium) as well as in 73 patients who had not received any nondepolarizing NMB. After each survey, the results were presented to the entire department, along with discussions of individual cases, reviews of the recent literature regarding quantitative monitoring and further education regarding the use of the quantitative system. RESULTS: In the initial (August 2011) PACU survey of 96 patients receiving nondepolarizing NMBs, 31% had a TOF ratio of ≤0.9, 17% had a ratio of ≤0.8, and 4 patients (4%) had ratios of ≤0.5. A record review showed that the quantitative monitoring system had been used to monitor reversal in only 51% of these patients, and 23% of patients had no evidence of any monitoring, including qualitative TOF assessment. By December of 2012 (after 2 interim PACU monitoring surveys), a fourth survey showed 15% of 101 monitored patients had a TOF ratio ≤0.9, and only 5% had ratios ≤0.8. (P < 0.05 vs August 2011). Clear documentation of reversal using the quantitative system was present in 83% of cases (P < 0.05 vs August 2011). A final survey in July 2013 showed nearly identical values to those from December 2012. The lowest TOF ratio observed in any patient not receiving a nondepolarizing NMB was 0.92. There were no changes in the patterns of either rocuronium or neostigmine use over the duration of the project (through December 2012), and there have been no cases of NMB-related reintubations in the PACU during the last 2 years. DISCUSSION: Implementation of universal electromyographic-based quantitative neuromuscular blockade monitoring required a sustained process of education along with repeated PACU surveys and feedback to providers. Nevertheless, this effort resulted in a significant reduction in the incidence of incompletely reversed patients in the PACU.

Bayesian methods to determine performance differences and to quantify variability among centers in multi-center trials: the IHAST trial.

BACKGROUND: To quantify the variability among centers and to identify centers whose performance are potentially outside of normal variability in the primary outcome and to propose a guideline that they are outliers. METHODS: Novel statistical methodology using a Bayesian hierarchical model is used. Bayesian methods for estimation and outlier detection are applied assuming an additive random center effect on the log odds of response: centers are similar but different (exchangeable). The Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST) is used as an example. Analyses were adjusted for treatment, age, gender, aneurysm location, World Federation of Neurological Surgeons scale, Fisher score and baseline NIH stroke scale scores. Adjustments for differences in center characteristics were also examined. Graphical and numerical summaries of the between-center standard deviation (sd) and variability, as well as the identification of potential outliers are implemented. RESULTS: In the IHAST, the center-to-center variation in the log odds of favorable outcome at each center is consistent with a normal distribution with posterior sd of 0.538 (95% credible interval: 0.397 to 0.726) after adjusting for the effects of important covariates. Outcome differences among centers show no outlying centers. Four potential outlying centers were identified but did not meet the proposed guideline for declaring them as outlying. Center characteristics (number of subjects enrolled from the center, geographical location, learning over time, nitrous oxide, and temporary clipping use) did not predict outcome, but subject and disease characteristics did. CONCLUSIONS: Bayesian hierarchical methods allow for determination of whether outcomes from a specific center differ from others and whether specific clinical practices predict outcome, even when some centers/subgroups have relatively small sample sizes. In the IHAST no outlying centers were found. The estimated variability between centers was moderately large.

Research, education, and nonclinical service productivity of new junior anesthesia faculty during a 2-year faculty development program.

BACKGROUND: As a specialty, anesthesiology has relatively low research productivity. Prior studies indicate that junior faculty development programs favorably affect academic performance. We therefore initiated a junior faculty development program and hypothesized that most (>50%) new junior faculty would take <50 nonclinical days to achieve a primary program goal (e.g., investigation or publication), and <5 nonclinical days to achieve a secondary program goal (e.g., teaching or nonclinical service). METHODS: Twenty new junior faculty participated in the 2-year program which had a goal-oriented structure and was supported by nonclinical time, formally assigned mentors, and a didactic curriculum. Goal productivity equaled the number of program goals accomplished divided by the amount of nonclinical time received. Primary goal productivity was expressed as primary goals accomplished per 50 nonclinical days. Secondary goal productivity was expressed as secondary goals accomplished per 5 nonclinical days. RESULTS: Median primary goal productivity was 0.45 primary goals per 50 nonclinical days (25th-75th interquartile range = 0.00-0.73). Contrary to our hypothesis, most new junior faculty needed >50 nonclinical days to achieve a primary goal (17/20, P = 0.0026). Median secondary goal productivity was 0.57 secondary goals per 5 nonclinical days (25th-75th interquartile range = 0.38-0.77). Contrary to our hypothesis, most new junior faculty needed >5 nonclinical days to accomplish a secondary goal (18/20, P = 0.0004). It was not clear that the faculty development program increased program goal productivity. CONCLUSIONS: Even with structured developmental support, most new junior anesthesia faculty needed >50 nonclinical days to achieve a primary (traditional academic) goal and >5 nonclinical days to achieve a secondary goal. Currently, most new anesthesia faculty are not productive in traditional academic activities (research). They are more productive in activities related to clinical care, education, and patient care systems management.

Are anesthesia and surgery during infancy associated with altered academic performance during childhood?

BACKGROUND: Although studies in neonatal animals show that anesthetics have neurotoxic effects, relevant human evidence is limited. We examined whether children who had surgery during infancy showed deficits in academic achievement. METHODS: We attempted to contact parents of 577 children who, during infancy, had one of three operations typically performed in otherwise healthy children. We compared scores on academic achievement tests with population norms. RESULTS: Composite scores were available for 287 patients. The mean normal curve equivalent score was 43.0±22.4 (mean±SD), lower than the expected normative value of 50, P<0.0001 by one-sample Student t test; and 35 (12%) had scores below the 5th percentile, more than expected, P<0.00001 by binomial test. Of 133 patients who consented to participate so that their scores could be examined in relation to their medical records, the mean score was 45.9±22.9, P=0.0411; and 15 (11%) scored below the 5th percentile, P=0.0039. Of 58 patients whose medical records showed no central nervous system problems/potential risk factors during infancy, 8 (14%) scored below the 5th percentile, P=0.008; however, the mean score, 47.6±23.4, was not significantly lower than expected, P=0.441. Duration of anesthesia and surgery correlated negatively with scores (r=-0.34, N=58, P=0.0101). CONCLUSIONS: Although the findings are consistent with possible adverse effects of anesthesia and surgery during infancy on subsequent academic achievement, other explanations are possible and further investigations are needed.