Neural interfacing architecture enables enhanced motor control and residual limb functionality postamputation.

Despite advancements in prosthetic technologies, patients with amputation today suffer great diminution in mobility and quality of life. We have developed a modified below-knee amputation (BKA) procedure that incorporates agonist-antagonist myoneural interfaces (AMIs), which surgically preserve and couple agonist-antagonist muscle pairs for the subtalar and ankle joints. AMIs are designed to restore physiological neuromuscular dynamics, enable bidirectional neural signaling, and offer greater neuroprosthetic controllability compared to traditional amputation techniques. In this prospective, nonrandomized, unmasked study design, 15 subjects with AMI below-knee amputation (AB) were matched with 7 subjects who underwent a traditional below-knee amputation (TB). AB subjects demonstrated significantly greater control of their residual limb musculature, production of more differentiable efferent control signals, and greater precision of movement compared to TB subjects (P < 0.008). This may be due to the presence of greater proprioceptive inputs facilitated by the significantly higher fascicle strains resulting from coordinated muscle excursion in AB subjects (P < 0.05). AB subjects reported significantly greater phantom range of motion postamputation (AB: 12.47 ± 2.41, TB: 10.14 ± 1.45 degrees) when compared to TB subjects (P < 0.05). Furthermore, AB subjects also reported less pain (12.25 ± 5.37) than TB subjects (17.29 ± 10.22) and a significant reduction when compared to their preoperative baseline (P < 0.05). Compared with traditional amputation, the construction of AMIs during amputation confers the benefits of enhanced physiological neuromuscular dynamics, proprioception, and phantom limb perception. Subjects' activation of the AMIs produces more differentiable electromyography (EMG) for myoelectric prosthesis control and demonstrates more positive clinical outcomes.

The Use of Unlisted Billing Codes for Microsurgical Breast Reconstruction and Implications for Code Consolidation.

BACKGROUND: Private insurers have considered consolidating the billing codes presently available for microvascular breast reconstruction. There is a need to understand how these different codes are currently distributed and used to help inform how coding consolidation may impact patients and providers. METHODS: Using the Massachusetts All-Payer Claims Database between 2016 and 2020, patients who underwent microsurgical breast reconstruction following mastectomy for cancer-related indications were identified. Multivariable logistic regression was used to test whether an S2068 claim was associated with insurance type and median household income by patient ZIP code. The ratio of S2068 to CPT19364 claims for privately insured patients was calculated for providers practicing in each county. Total payments for professional fees were compared between billing codes. RESULTS: There were 272 claims for S2068 and 209 claims for CPT19364. An S2068 claim was associated with age < 45 years (OR: 1.89, 95% CI: 1.11-3.20, p = 0.019), more affluent ZIP codes (OR: 1.11, 95% CI: 1.03-1.19, p = 0.004), and private insurance (OR: 16.13, 95% CI: 7.81-33.33, p < 0.001). Median total payments from private insurers were 101% higher for S2068 than for CPT19364. In all but two counties (Worcester and Hampshire), the S-code was used more frequently than CPT19364 for their privately insured patients. CONCLUSION: Coding practices for microsurgical breast reconstruction lacked uniformity in Massachusetts, and payments differed greatly between S2068 and CPT19364. Patients from more affluent towns were more likely to have S-code claims. Coding consolidation could impact access, as the majority of providers in Massachusetts might need to adapt their practices if the S-code were discontinued.

Optimal Timing of Delayed Microvascular Breast Reconstruction after Radiation Therapy.

BACKGROUND: The purpose of this study was to determine the optimal timing of delayed microvascular breast reconstruction after completion of postmastectomy radiation therapy (PMRT). The authors evaluated whether the timing of reconstruction after PMRT completion affects the development of major postoperative complications. We hypothesize that delayed microvascular breast reconstruction can be safely performed within 12 months of PMRT completion. METHODS: A retrospective chart review of microvascular, autologous breast reconstructions at Brigham and Women's Hospital from 2007 to 2019 was performed. Logistic regression analysis and marginal estimation methods were used to estimate the probability of any major complication (flap compromise requiring operative intervention, hematoma formation requiring evacuation, infection requiring readmission, and flap necrosis requiring operative debridement) occurring in 2-month intervals after PMRT. Patients were classified as having undergone reconstruction 0 to 12 months after PMRT (group 1), 12 to 18 months after PMRT (group 2), or 18 to 50 months after PMRT (group 3). RESULTS: A total of 303 patients were identified. All patients received postmastectomy radiation (n = 143 group 1, n = 57 group 2, n = 103 group 3). Mean follow-up time was 71.4 ± 38 months. Patients in group 1 were significantly younger and more likely to have undergone neoadjuvant chemotherapy (p < 0.05). Major complications occurred in 10% of patients. There was no significant difference in the development of major complications between the three groups (p = 0.57). Although not statistically significant, the probability of any major complication peaked 2 to 6 months after PMRT completion. CONCLUSION: There was no significant difference in major complications among patients who underwent delayed, microvascular breast reconstruction within versus beyond 1 year of PMRT completion. These findings suggest that delayed microvascular breast reconstruction can be safely performed beginning 6 months after PMRT completion.

Reinventing Extremity Amputation in the Era of Functional Limb Restoration.

BACKGROUND: Recent progress in biomechatronics and vascularized composite allotransplantation have occurred in the absence of congruent advancements in the surgical approaches generally utilized for limb amputation. Consideration of these advances, as well as of both novel and time-honored reconstructive surgical techniques, argues for a fundamental reframing of the way in which amputation procedures should be performed. METHODS: We review sentinel developments in external prosthetic limb technology and limb transplantation, in addition to standard and emerging reconstructive surgical techniques relevant to limb modification, and then propose a new paradigm for limb amputation. RESULTS: An approach to limb amputation based on the availability of native tissues is proposed, with the intent of maximizing limb function, limiting neuropathic pain, restoring limb perception/proprioception and mitigating limb atrophy. CONCLUSIONS: We propose a reinvention of the manner in which limb amputations are performed, framed in the context of time-tested reconstructive techniques, as well as novel, state-of-the-art surgical procedures. Implementation of the proposed techniques in the acute setting has the potential to elevate advanced limb replacement strategies to a clinical solution that perhaps exceeds what is possible through traditional surgical approaches to limb salvage. We therefore argue that amputation, performed with the intent of optimizing the residuum for interaction with either a bionic or a transplanted limb, should be viewed not as a surgical failure, but as an alternative form of limb reconstruction.

The Agonist-antagonist Myoneural Interface.

Scientist and technologist have long sought to advance limb prostheses that connect directly to the peripheral nervous system, enabling a person with amputation to volitionally control synthetic actuators that move, stiffen and power the prosthesis, as well as to experience natural afferent sensations from the prosthesis. Recently, the agonist-antagonist myoneural interface (AMI) was developed, a mechanoneural transduction architecture and neural interface system designed to provide persons with amputation improved muscle-tendon proprioception and neuroprosthetic control. In this paper, we provide an overview of the AMI, including its conceptual framing and pre-clinical science, surgical techniques for its construction, and clinical efficacy related to pain mitigation, phantom limb range of motion, fascicle dynamics, central brain proprioceptive sensorimotor preservation, and prosthetic controllability. Following this broad overview, we end with a discussion of current limitations of the AMI and potential resolutions to such challenges.

Hospital Length of Stay Reduction Over Time and Patient Readmission for Severe Adverse Events Following Surgery.

OBJECTIVE: The aim of the study was to investigate whether patients who undergo surgery in hospitals experiencing significant length of stay (LOS) reductions over time are exposed to a higher risk of severe adverse events in the postoperative period. SUMMARY BACKGROUND DATA: Surgical care innovation has encouraged hospitals to shorten LOS under financial pressures with uncertain impact on patient outcomes. METHODS: We selected all patients who underwent elective colectomy or urgent hip fracture repair in French hospitals between 2013 and 2016. For each procedure, hospitals were categorized into 3 groups according to variations in their median LOS as follows: major decrease, moderate decrease, and no decrease. These groups were matched using propensity scores based on patients' and hospitals' potential confounders. Potentially avoidable readmission for severe adverse events and death at 6 months were compared between groups using Cox regressions. RESULTS: We considered 98,713 patients in 540 hospitals for colectomy and 206,812 patients in 414 hospitals for hip fracture repair before matching. After colectomy, patient outcomes were not negatively impacted when hospitals reduced their LOS [hazard ratio (95% confidence interval): 0.93 (0.78-1.10)]. After hip fracture repair, patients in hospitals with major decreases in LOS had a higher risk of severe adverse events [1.22 (1.11-1.34)] and death [1.17 (1.04-1.32)]. CONCLUSIONS: Patients who underwent surgical procedures in hospitals experiencing major decreases in LOS were demonstrated worse postoperative outcomes after urgent hip fracture repair and not after elective colectomy. Development of care bundles to enhance recovery after emergency surgeries may allow better control of LOS reduction and patient outcomes.

Influence of trends in hospital volume over time on patient outcomes for high-risk surgery.

BACKGROUND: The "practice makes perfect" concept considers the more frequent a hospital performs a procedure, the better the outcome of the procedure. We aimed to study this concept by investigating whether patient outcomes improve in hospitals with a significantly increased volume of high-risk surgery over time and whether a learning effect existed at the individual hospital level. METHODS: We included all patients who underwent one of 10 digestive, cardiovascular and orthopaedic procedures between 2010 and 2014 from the French nationwide hospitals database. For each procedure, we identified three groups of hospitals according to volume trend (increased, decreased, or no change). In-hospital mortality, reoperation, and unplanned hospital readmission within 30 days were compared between groups using Cox regressions, taking into account clustering of patients within hospitals and potential confounders. Individual hospital learning effect was investigated by considering the interaction between hospital groups and procedure year. RESULTS: Over 5 years, 759,928 patients from 694 hospitals were analysed. Patients' mortality in hospitals with procedure volume increase or decrease over time did not clearly differ from those in hospitals with unchanged volume across the studied procedures (e.g., Hazard Ratios [95%] of 1.04 [0.93-1.17] and 1.08 [0.97-1.21] respectively for colectomy). Furthermore, patient outcomes did not improve or deteriorate in hospitals with increased or decreased volume of procedures over time (e.g., 1.01 [0.95-1.08] and 0.99 [0.92-1.05] respectively for colectomy). CONCLUSIONS: Trend in hospital volume over time did not appear to influence patient outcomes based on real-world data. TRIAL REGISTRATION: NCT02788331, June 2, 2016.

Content Validity of the LIMB-Q: A Patient-Reported Outcome Instrument for Lower Extremity Trauma Patients.

BACKGROUND: Limb-threatening lower extremity traumatic injuries can be devastating events with a multifaceted impact on patients. Therefore, evaluating patient-reported outcomes (PROs) in addition to traditional surgical outcomes is important. However, currently available instruments are limited as they were not developed specific to lower extremity trauma patients and lack content validity. The LIMB-Q is being developed as a novel PRO instrument to meet this need, with the goal to measure all relevant concepts and issues impacting amputation and limb-salvage patients after limb-threatening lower extremity trauma. METHODS: This is a qualitative interview-based study evaluating content validity for the LIMB-Q. Patients aged 18 years and older who underwent amputation, reconstruction, or amputation after failed reconstruction were recruited using purposeful sampling to maximize variability of participant experiences. Expert opinion was solicited from a variety of clinical providers and qualitative researchers internationally. Preliminary items and scales were modified, added, or removed based on participant and expert feedback after each round of participant interviews and expert opinion. RESULTS: Twelve patients and 43 experts provided feedback in a total of three rounds, with changes to the preliminary instrument made between each round. One scale was dropped after round one, one scale was added after round two, and only minor changes were needed after round three. Modifications, additions and removal of items, instructions, and response options were made after each round using feedback gathered. CONCLUSION: The LIMB-Q was refined and modified to reflect feedback from patients and experts in the field. Content validity for the LIMB-Q was established. Following a large-scale field test, the LIMB-Q will be ready for use in research and clinical care.

Innovations in reconstructive microsurgery: Reconstructive transplantation.

In the past 20 years, reconstructive transplantation (RT) has emerged as a viable reconstructive option for carefully selected patients. More than 100 upper extremity and 40 face transplants have been performed worldwide to date. Concomitantly, the portfolio of reconstructive transplantation has been extended by additional procedures such as lower extremities, abdominal wall, neck, uterus, genitourinary, and pediatric transplants. In the present review article, we aim to summarize the current state of knowledge about this exciting field.

Methodological Quality of Surgical Mortality Studies Using Large Hospital Databases: A Systematic Review.

OBJECTIVE: To review the methodology employed in surgical mortality studies to control for potential confounders. SUMMARY BACKGROUND DATA: Nationwide hospital data are increasingly used to investigate surgical outcomes. However, poor data granularity and coding inaccuracies may lead to flawed findings. METHODS: We conducted a systematic review in accordance with the PRISMA statement in 6 major journals (NEJM, Lancet, BMJ, JAMA, Medical Care, Annals of Surgery) using PubMed from its inception until December 31, 2014. Two reviewers independently reviewed citations. Using a predesigned data collection form, we extracted information about study aim and design, data source, selected population, outcome definition, patient and hospital adjustment, statistics, and sensitivity analyses. The methodological quality of studies was assessed based on 5 criteria and explored over time. RESULTS: Among 89 included studies from 1987 to 2014, 54 explored surgical mortality determinants, 13 compared surgical procedure effectiveness, 13 evaluated the impact of healthcare policy, and 9 described outcome trends for specific procedures. A total of 89% (n = 79) of studies did not describe population selection criteria at patient and hospital level, 64% (n = 57) did not consider secular trends, 52% (n = 46) neglected hospital clustering or characteristics, 21% (n = 19) did not perform sensitivity analyses, and 4% did not adjust outcomes for patient risk (n = 4). The percentage of studies satisfying at least 3 of these criteria increased significantly from 44% before 1999 to 52% between 2000 and 2009 and 78% after 2010 (P = 0.008). CONCLUSIONS: Although methodological quality of studies has improved over time, confounder control could be improved through better study design, homogeneous population selection, the consideration of hospital factors and secular trends influencing surgical mortality, and the systematic performance of sensitivity analyses.

The influence of volume and experience on individual surgical performance: a systematic review.

OBJECTIVE: To systematically review studies evaluating the influence of surgical experience on individual performance. BACKGROUND: Experience, measured in case volume or years of practice, is recognized as a key driver of individual surgical performance, giving rise to a learning curve. However, this topic has not been reviewed at the cross-specialty level. METHODS: MEDLINE, EMBASE, PsycINFO, AMED, and the Cochrane Database of Systematic Reviews were searched (from inception to February 2013). Two reviewers independently reviewed citations using predetermined inclusion and exclusion criteria. Ninety-one data points per study were extracted. RESULTS: The search strategy yielded 6950 citations. Fifty-seven studies were eligible, including 1,061,913 cases and 35 procedure types, performed by 17,912 surgeons. Forty-five studies monitored case volume, and 6 studies measured experience as both case volume and years of practice. Of these 51 studies, 44 found that increased case volume was associated with significantly improved health outcomes. Several studies noted a plateau phase or maturation in the surgical learning curve. Acquisition of this phase was procedure specific and outcome specific, ranging from 25 to 750 procedures. Twelve studies assessed the impact of years of surgical practice, 11 of which found that increased years of experience was associated with significantly improved health outcomes. Two studies noted a plateau phase, where increases in years of experience were no longer associated with improvements in operative outcomes. Three studies identified performance deterioration after the plateau phase. CONCLUSIONS: Increasing surgical case volume and years of practice are associated with improved performance, in a procedure-specific manner. Performance may deteriorate toward the end of a surgeon's career.

Three patients with full facial transplantation.

Unlike conventional reconstruction, facial transplantation seeks to correct severe deformities in a single operation. We report on three patients who received full-face transplants at our institution in 2011 in operations that aimed for functional restoration by coaptation of all main available motor and sensory nerves. We enumerate the technical challenges and postoperative complications and their management, including single episodes of acute rejection in two patients. At 6 months of follow-up, all facial allografts were surviving, facial appearance and function were improved, and glucocorticoids were successfully withdrawn in all patients.

The impact of feedback of surgical outcome data on surgical performance: a systematic review.

BACKGROUND: Increasing patient demands, costs and emphasis on safety have led to performance tracking of individual surgeons. Several methods of using these data, including feedback have been proposed. Our aim was to systematically review the impact of feedback of outcome data to surgeons on their performance. STUDY DESIGN: MEDLINE, Embase, PsycINFO, AMED and the Cochrane Database of Systematic Reviews (from their inception to February 2013) were searched. Two reviewers independently reviewed citations using predetermined inclusion and exclusion criteria. Forty two data-points per study were extracted. RESULTS: The search strategy yielded 1,531 citations. Seven studies were eligible comprising 18,632 cases or procedures by 52 surgeons. Overall, feedback was found to be a powerful method for improving surgical outcomes or indicators of surgical performance, including reductions in hospital mortality after CABG of 24% (P = 0.001), decreases of stroke and mortality following carotid endarterectomy from 5.2 to 2.3%, improved ovarian cancer resection from 77 to 85% (P = 0.157) and reductions in wound infection rates from 14 to 10.3%. Improvements in performance occurred in concert with reduced costs: for hepaticojejunostomy, implementation of feedback was associated with a decrease in overall hospital costs from $24,446 to $20,240 (P < 0.01). Similarly, total cost of carotid endarterectomy and following management decreased from $13,344 to $9548. CONCLUSIONS: The available literature suggests that feedback can improve surgical performance and outcomes; however, given the heterogeneity and limited number of studies, in addition to their non-randomised nature, it is difficult to draw clear conclusions from the literature with regard to the efficacy of feedback and the specific nuances required to optimise the impact of feedback. There is a clear need for more rigorous studies to determine how feedback of outcome data may impact performance, and whether this low-cost intervention has potential to benefit surgical practice.

A time-adjusted control chart for monitoring surgical outcome variations.

BACKGROUND: Statistical Process Control (SPC) tools providing feedback to surgical teams can improve patient outcomes over time. However, the quality of routinely available hospital data used to build these tools does not permit full capture of the influence of patient case-mix. We aimed to demonstrate the value of considering time-related variables in addition to patient case-mix for detection of special cause variations when monitoring surgical outcomes with control charts. METHODS: A retrospective analysis from the French nationwide hospital database of 151,588 patients aged 18 and older admitted for colorectal surgery between January 1st, 2014, and December 31st, 2018. GEE multilevel logistic regression models were fitted from the training dataset to predict surgical outcomes (in-patient mortality, intensive care stay and reoperation within 30-day of procedure) and applied on the testing dataset to build control charts. Surgical outcomes were adjusted on patient case-mix only for the classical chart, and additionally on secular (yearly) and seasonal (quarterly) trends for the enhanced control chart. The detection of special cause variations was compared between those charts using the Cohen's Kappa agreement statistic, as well as sensitivity and positive predictive value with the enhanced chart as the reference. RESULTS: Within the 5-years monitoring period, 18.9% (28/148) of hospitals detected at least one special cause variation using the classical chart and 19.6% (29/148) using the enhanced chart. 59 special cause variations were detected overall, among which 19 (32.2%) discordances were observed between classical and enhanced charts. The observed Kappa agreement between those charts was 0.89 (95% Confidence Interval [95% CI], 0.78 to 1.00) for detecting mortality variations, 0.83 (95% CI, 0.70 to 0.96) for intensive care stay and 0.67 (95% CI, 0.46 to 0.87) for reoperation. Depending on surgical outcomes, the sensitivity of classical versus enhanced charts in detecting special causes variations ranged from 0.75 to 0.89 and the positive predictive value from 0.60 to 0.89. CONCLUSION: Seasonal and secular trends can be controlled as potential confounders to improve signal detection in surgical outcomes monitoring over time.

Continuous neural control of a bionic limb restores biomimetic gait after amputation.

For centuries scientists and technologists have sought artificial leg replacements that fully capture the versatility of their intact biological counterparts. However, biological gait requires coordinated volitional and reflexive motor control by complex afferent and efferent neural interplay, making its neuroprosthetic emulation challenging after limb amputation. Here we hypothesize that continuous neural control of a bionic limb can restore biomimetic gait after below-knee amputation when residual muscle afferents are augmented. To test this hypothesis, we present a neuroprosthetic interface consisting of surgically connected, agonist-antagonist muscles including muscle-sensing electrodes. In a cohort of seven leg amputees, the interface is shown to augment residual muscle afferents by 18% of biologically intact values. Compared with a matched amputee cohort without the afferent augmentation, the maximum neuroprosthetic walking speed is increased by 41%, enabling equivalent peak speeds to persons without leg amputation. Further, this level of afferent augmentation enables biomimetic adaptation to various walking speeds and real-world environments, including slopes, stairs and obstructed pathways. Our results suggest that even a small augmentation of residual muscle afferents restores biomimetic gait under continuous neuromodulation in individuals with leg amputation.

The teaming curve: a longitudinal study of the influence of surgical team familiarity on operative time.

OBJECTIVE: To quantify the association between surgical team familiarity and operative time. BACKGROUND: Team familiarity in the operating room may influence outcomes irrespective of individual surgeons' experience. To date, however, quantifying the impact of teamwork on outcomes has been challenging. METHODS: We studied 754 bilateral reduction mammaplasty procedures performed by 223 teams, comprising 8 attending surgeons and 107 assisting surgeons, at a major academic hospital between 1995 and 2007. For each procedure, the operative experience of the attending and assisting surgeons and the number of mammaplasty procedures they had previously performed in collaboration were determined. The influence of these factors on operative time was quantified along with patient age, volume of breast reduction, and comorbidities, using multivariate generalized estimating equations. RESULTS: The mean operative time was 153 (SD = 38) minutes for teams with no prior collaborations, 132 (SD = 33) minutes for teams with 1 to 5 collaborations, 116 (SD = 23) minutes for teams with 6 to 10 collaborations, and 119 (SD = 27) minutes for teams with more than 10 collaborations (P = 0.0001). Operative time was independently associated with the operative experience of the attending (P = 0.02) and assisting surgeons (P = 0.03) and the number of prior collaborations between them (P < 0.001). The expected reductions in operative time over the attending surgeon's career and the assisting surgeon's training period were 59 and 22 minutes, respectively. Surgical team familiarity accounted for an additional reduction of 16 minutes after 10 prior collaborations. CONCLUSIONS: In addition to individual surgeon experience, team familiarity contributed to reductions in operative time, suggesting potential benefits to maintaining continuity of team membership over time.

Temporal variation in surgical mortality within French hospitals.

BACKGROUND: Surgical mortality varies widely across hospitals, but the degree of temporal variation within individual hospitals remains unexplored and may reflect unsafe care. OBJECTIVES: To add a longitudinal dimension to large-scale profiling efforts for interpreting surgical mortality variations over time within individual hospitals. DESIGN: Longitudinal analysis of the French nationwide hospital database using statistical process control methodology. SUBJECTS: A total of 9,474,879 inpatient stays linked with open surgery from 2006 through 2010 in 699 hospitals. MEASURES: For each hospital, a control chart was designed to monitor inpatient mortality within 30 days of admission and mortality trend was determined. Aggregated funnel plots were also used for comparisons across hospitals. RESULTS: Over 20 successive quarters, 52 hospitals (7.4%) experienced the detection of at least 1 potential safety issue reflected by a substantial increase in mortality momentarily. Mortality variation was higher among these institutions compared with other hospitals (7.4 vs. 5.0 small variation signals, P<0.001). Also, over the 5-year period, 119 (17.0%) hospitals reduced and 36 (5.2%) increased their mortality rate. Hospitals with improved outcomes had better control of mortality variation over time than those with deteriorating trends (5.2 vs. 6.3 signals, P=0.04). Funnel plots did not match with hospitals experiencing mortality variations over time. CONCLUSIONS: Dynamic monitoring of outcomes within every hospital may detect safety issues earlier than traditional benchmarking and guide efforts to improve the value of surgical care nationwide.

Boston bombings: a surgical view of lessons learned from combat casualty care and the applicability to Boston's terrorist attack.

The Boston bombing incident was a recent civilian mass casualty terrorist event that demonstrated effective transfer of the lessons of combat casualty care to inform effective civilian medical care. Thirty-nine patients were seen at Brigham and Women's Hospital and thirteen patients received emergency surgery in the first few hours after the event. The subsequent management, total hospital days 181, total number of operative procedures 72, and discharging service listing of these thirteen patients illustrate the intensive surgical resources necessary after a civilian bomb attack. Plastic surgery played a role in the multidisciplinary collaboration of the limb salvage efforts and this role can inform the importance of other plastic surgery contributions within mass casualty surgical management. We believe that prepositioned collaborative relationships of plastic surgery, vascular surgery, trauma surgery and orthopedic surgery may offer a model of collaboration for limb salvage that can be applied in military and mass casualty medical care if resources permit. In this attack, effective use of tourniquets was implemented by prehospital medical providers that saved lives and limbs and these actions reaffirm the important lessons learned from combat casualty care. Unfortunately, it is likely that more centers will deal with similar events in the future and it is imperative that we as a community of providers take what lessons we can from battlefield medicine and that we collectively prepare for and engage this future.

Control Charts Usage for Monitoring Performance in Surgery: A Systematic Review.

OBJECTIVES: The control chart is a graphical tool for data interpretation that detects aberrant variations in specific metrics, ideally leading to the identification of special causes that can be resolved. A clear assessment of control chart utilization and its potential impact in surgery is required to justify recommendations for its dissemination. This review aims to describe how performance monitoring using control charts was used over time in surgery. METHODS: A systematic search of PubMed regarding statistical process control in surgery from its inception until December 2019 was performed using Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Information extracted from selected publications included study aim and population setting, monitored indicators, control charts methodological parameters, and implementation strategy. RESULTS: One hundred thirteen studies met the selection criteria with a median of 1916 monitored patients. Overall, 57.5% of studies focused on control chart methodology, 24.8% aimed at evaluating performance changes using control charts retrospectively, and 17.7% implemented control charts for continuous quality improvement prospectively. Although there was a great diversity of used indicators and charting tools, the evaluation of patient safety (72.6%) or efficiency (15.9%) metrics based on Shewhart control chart (33.6%) or cumulative sum chart (54.9%) were common. To foster control charts implementation, 14 studies promoted their periodic review, but only three assessed their impact on patient outcomes. CONCLUSIONS: The scientific literature supports the feasibility and utility of control chart to improve patient safety in multiple surgical settings. Additional studies are necessary to reveal the optimal manner in which to implement this affordable tool in surgical practice.