Constructing synthetic datasets with generative artificial intelligence to train large language models to classify acute renal failure from clinical notes.

OBJECTIVES: To compare performances of a classifier that leverages language models when trained on synthetic versus authentic clinical notes. MATERIALS AND METHODS: A classifier using language models was developed to identify acute renal failure. Four types of training data were compared: (1) notes from MIMIC-III; and (2, 3, and 4) synthetic notes generated by ChatGPT of varied text lengths of 15 (GPT-15 sentences), 30 (GPT-30 sentences), and 45 (GPT-45 sentences) sentences, respectively. The area under the receiver operating characteristics curve (AUC) was calculated from a test set from MIMIC-III. RESULTS: With RoBERTa, the AUCs were 0.84, 0.80, 0.84, and 0.76 for the MIMIC-III, GPT-15, GPT-30- and GPT-45 sentences training sets, respectively. DISCUSSION: Training language models to detect acute renal failure from clinical notes resulted in similar performances when using synthetic versus authentic training data. CONCLUSION: The use of training data derived from protected health information may not be needed.

Evaluation of the accuracy and intra- and interobserver reliability of three manual laxity tests for canine cranial cruciate ligament rupture-An ex vivo kinetic and kinematic study.

OBJECTIVES: To investigate the accuracy and intra- and interobserver reliability of the cranial drawer test (CD), tibial compression test (TCT), and the new tibial pivot compression test (TPCT) in an experimental setting resembling acute cranial cruciate ligament rupture (CCLR) and to elucidate the ability to subjectively estimate cranial tibial translation (CTT) during testing. STUDY DESIGN: Experimental ex vivo study. SAMPLE POPULATION: Ten cadaveric hindlimbs of large dogs. METHODS: Kinetic and 3D-kinematic data was collected while three observers performed the tests on each specimen with intact (INTACT) and transected cranial cruciate ligament (CCLD) and compared using three-way repeated-measures ANOVA. Subjectively estimated CTT (SCTT), obtained during a separate round of testing, was compared to kinematic data by Pearson correlation. RESULTS: CTT was significantly higher for CCLD than for INTACT for all tests, resulting in 100% sensitivity and specificity. TPCT induced the highest CTT and internal rotation. Intra- and interobserver agreement of translation was excellent. For rotation and kinetics, agreement was more variable. SCTT strongly correlated with the objectively measured values. CONCLUSION: The CD, TCT and the new TPCT were all accurate and reliable. The high translations and rotations during TPCT are promising, encouraging further development of this test. SCTT was reliable in our experimental setting. CLINICAL SIGNIFICANCE: Veterinary manual laxity tests are accurate and reliable in acute CCLR. The TPCT might have potential for the assessment of subtle and rotational canine stifle instabilities. The high reliability of SCTT implies that grading schemes for stifle laxity, similar to human medicine, could be developed.

The assessment of a growing mobile anesthesia practice from 2016 to 2019: A retrospective observational cohort study of 89,999 cases comparing ambulatory surgery (ASC) and office-based surgery (OBS) centers using a high-fidelity, anesthesia-specific electronic medical record (EMR).

Office-based surgery (OBS) has emerged as a significant subspecialty of ambulatory surgery. There are few clinical trials and limited published data on patient characteristics, anesthesia, or outcomes distinguishing OBS from ambulatory surgery centers (ASCs). We examined retrospective data from a large mobile anesthesia practice for 89,999 procedures from 2016 to 2019. Data was abstracted from billing and an anesthesia-specific electronic medical record, segregating procedures performed in ASCs versus OBS. The number and breadth of procedures increased substantially. Compared to ASCs, OBS patients were more likely male (52% vs. 48%), older (61 years vs. 55 years), and to have a higher American Society of Anesthesiologists (ASAs) status (33% vs. 20% ASA 3 or higher). The procedure mix varied substantially between the two settings. The major complication rate was 0.07% for the ASCs and 0.24% for OBS (p = 0.2, confidence interval [CI] -0.15 to 0.04). Minor complications were 11.2% in OBS versus 17.3% the ASCs (p < 0.0001, 95% CI 5.2-7). The practice demonstrates a low rate of complications, and despite the limitations of this study, the organization and structure of this large mobile anesthesia practice serves as a template for effective risk mitigation and patient safety.

Femorotibial joint kinematics in nine dogs treated with lateral suture stabilization for complete cranial cruciate ligament rupture.

OBJECTIVE: To quantify 3-D femorotibial joint kinematics during ambulation in dogs with cranial cruciate ligament (CCL) rupture treated with lateral fabellotibial suture stabilization (LFTS). ANIMALS: 9 adult dogs (body weight, 15 to 35 kg [33 to 77 lb]) with unilateral complete CCL rupture. PROCEDURES: Digital 3-D bone models of the femur and fabellae and tibia and fibula were created from CT scans. Lateral fluoroscopic images of stifle joints were collected during treadmill walking before surgery and 6 months after LFTS. The LFTS was performed with nylon leader material secured with knots. Gait cycles were analyzed with a 3-D to 2-D image registration process. Femorotibial joint kinematics (craniocaudal translation, internal-external rotation, and flexion and extension angles) were compared among CCL-deficient stifle joints before LFTS, CCL-deficient stifle joints 6 months after LFTS, and unaffected contralateral (control) stifle joints. Owners and veterinarians subjectively assessed lameness by use of a visual analog scale and gait examination, respectively, at each time point. RESULTS: At midstance phase, medial cranial tibial translation decreased from 9.3 mm before LFTS to 7.6 mm after LFTS but remained increased when compared with control stifle joint values. Following LFTS, axial rotation and stifle joint flexion and extension angles were not significantly different from control stifle joints. On the owner survey, the median walking lameness score improved from 9.3 of 10 before surgery to 0.3 after surgery. On gait examination, median walking lameness score improved from 2 of 4 before surgery to 0 after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Stifle joint instability was only slightly mitigated at 6 months following LFTS performed with knotted nylon leader material in medium to large dogs with CCL rupture, despite improvement in lameness.

Preoperative Anemia Treatment with Intravenous Iron Therapy in Patients Undergoing Abdominal Surgery: A Systematic Review.

INTRODUCTION: Preoperative anemia is associated with increased morbidity, mortality, and healthcare costs. As a result of the increased incidence of chronic blood loss and iron deficiency anemia in abdominal surgery patients and its impact on patient outcomes, we systematically evaluated the quality of evidence for preoperative intravenous (IV) administration of iron to patients with anemia undergoing major abdominal surgery with the focus on clinical outcomes. METHODS: In this systematic review, PubMed, Cochrane, The Cumulative Index to Nursing and Allied Health Literature, Web Of Science, and Excerpta Medica Database databases were searched up to 2019 using specific keywords. Inclusion criteria were patients that were over 18 years of age, underwent abdominal surgery, and received an IV iron treatment in the preoperative setting. RESULTS: The nine studies included in the final systematic review do not provide consistent evidence of a reduced incidence of allogeneic blood transfusions with preoperative IV iron administration. However, IV iron administration did consistently cause a significant increase in hemoglobin levels relative to oral iron therapy or no iron. CONCLUSION: Overall, these findings are consistent in that IV iron administration is highly effective at rapidly increasing hemoglobin levels in patients with iron deficiency anemia undergoing major abdominal surgery. Unfortunately, there is currently no evidence of reduced incidence of allogeneic blood transfusions or other enhanced outcomes.

Biomechanical comparison of ex vivo lumbar vertebral fracture luxations stabilized with tension band or polymethylmethacrylate in cats.

OBJECTIVE: To evaluate spinal stabilization with tension band stabilization (TS) in cats compared to screw and polymethylmethacrylate fixation (SP). STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Sixteen feline thoracolumbar spinal specimens. METHODS: The intact specimens were mounted in a six-degree-of-freedom biaxial testing machine for nondestructive testing to obtain the neutral zones (NZ) and range of motion (ROM) in flexion and extension. Thereafter, nondestructive testing was consecutively performed after destabilization by disc fenestration and partial L1 corpectomy and after treatment with either TS or SP. Load to failure was compared after surgical treatment in flexion. Significance was assessed by Student's t test or Wilcoxon signed-rank test. RESULTS: Range of motion was 26.4° ± 2.2° in TS constructs and 13.4° ± 2.1° in SP constructs (P = .0005). When flexion and extension were analyzed separately, no difference was found for ROM in flexion (SP, 7.0° ± 3.7°; TS, 8.3° ± 2.1°; P = .38). In extension, the mean displacement was 6.4° ± 2.7° and 18.1° ± 5.1° in SP and TS constructs, respectively (P = .0001). Neutral zone was 2.9° ± 0.6° and 7.5° ± 0.8° for the SP and TS groups, respectively (P = .0003). Screw and polymethylmethacrylate fixation constructs were two times stiffer (P = .045). CONCLUSION: Tension band stabilization provided stability comparable to SP in flexion. In extension, ROM of SP constructs was half that of TS constructs. The mode of failure of TS was related to the limited dorsal bone stock of feline lumbar vertebrae. CLINICAL SIGNIFICANCE: Surgeons should be aware of the limited stability in extension provided by TS when it is used to stabilize thoracolumbar spinal injuries. Our results provide evidence to justify additional studies to clarify the type of fractures amenable to TS.

Influence of a customized three-dimensionally printed drill guide on the accuracy of pedicle screw placement in lumbosacral vertebrae: An ex vivo study.

OBJECTIVE: To compare the accuracy of pedicle screw insertion (PSI) into canine lumbosacral vertebrae with custom-made three-dimensionally (3D)-printed drill guides or freehand insertion. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Nineteen canine lumbosacral specimens. METHODS: Drill guides for PSI were designed on the basis of safe screw insertion trajectories by using preoperative computed tomography (CT) and produced by 3D printing of templates. Right and left sides of the specimens were randomly allocated to two groups; 4-mm pedicle screws were inserted in L5-L6 and L7-S1 spinal segments either freehand (control group) or with custom-made drill guides (guide group). Sixty-six screws were inserted with each method. Insertion angles (α, ß), bone stock, and vertebral canal breach were assessed according to postoperative CT. χ2 Tests were used to compare vertebral canal breach between groups and vertebrae. RESULTS: Breaches in the vertebral canal were less common (P < .001) when screws were placed with a guide in the guide group (9/66, 14%) than without a guide (30/66, 45%). The rate of vertebral canal breach differed at L5 (P = .021) but not at L6 (P = .05), L7 (P = .075) or S1 (P = .658). The angle of insertion (α) did not differ between specimens with and without breaches (guide, P = .068; control, P = .394). CONCLUSION: The use of a customized 3D-printed guide generally improved the accuracy of PSI in canine lumbosacral vertebrae, although statistical significance was reached only at L5. CLINICAL SIGNIFICANCE: The use of customized drill guides may be considered as an alternative to freehand PSI in the lumbosacral area, especially for L5-L6 vertebrae.

I Tweet, Therefore I Learn: An Analysis of Twitter Use Across Anesthesiology Conferences.

BACKGROUND: Twitter in anesthesiology conferences promotes rapid science dissemination, global audience participation, and real-time updates of simultaneous sessions. We designed this study to determine if an association exists between conference attendance/registration and 4 defined Twitter metrics. METHODS: Using publicly available data through the Symplur Healthcare Hashtags Project and the Symplur Signals, we collected data on total tweets, impressions, retweets, and replies as 4 primary outcome metrics for all registered anesthesiology conferences occurring from May 1, 2016 to April 30, 2017. The number of Twitter participants, defined as users who contributed a tweet, retweet, or reply 3 days before through 3 days after the conference, was collected. We also collected influencer data as determined by mentions (number of times a user is referenced). Two authors independently verified the categories for influencers assigned by Symplur. Conference demographic data were obtained by e-mail inquiries. Associations between meeting attendees/registrants and Twitter metrics, between Twitter participants and the metrics, and between physician influencers and Twitter participants were tested using Spearman rho. RESULTS: Fourteen conferences with 63,180 tweets were included. With the American Society of Anesthesiologists annual meeting included, the correlations between meeting attendance/registration and total tweets (rs = 0.588; P = .074), impressions (rs = 0.527; P = .117), and retweets (rs = 0.539; P = .108) were not statistically significant; for replies, it was moderately positive (rs = 0.648; P = .043). Without the American Society of Anesthesiologists annual meeting, total tweets (rs = 0.433; P = .244), impressions (rs = 0.350; P = .356), retweets (rs = 0.367; P = .332), and replies (rs = 0.517; P = .154) were not statistically significant. Secondary outcomes include a highly positive correlation between Twitter participation and total tweets (rs = 0.855; P < .001), very highly positive correlations between Twitter participation and impressions (rs = 0.938; P < .001), retweets (rs = 0.925; P < .001), and a moderately positive correlation between Twitter participation and replies (rs = 0.652; P = .044). Doctors were top influencers in 8 of 14 conferences, and the number of physician influencers in the top 10 influencers list at each conference had a moderately positive correlation with Twitter participation (rs = 0.602; P = .023). CONCLUSIONS: We observed that the number of Twitter participants for a conference is positively associated with Twitter activity metrics. No relationship between conference size and Twitter metrics was observed. Physician influencers may be an important driver of participants.

Biomechanical comparison of knotted and knotless stabilization techniques of the tarsal medial collateral ligament in cats: A cadaveric study.

OBJECTIVE: To compare mechanical properties of intact feline medial collateral ligaments and three techniques for treatment of feline medial tarsal instability. STUDY DESIGN: Controlled laboratory study. SAMPLE POPULATION: Forty-eight normal, adult feline tarsi. METHODS: Three repairs were tested: a bone tunnel with polypropylene (PP) suture, a bone tunnel with polyethylene (PE) cord, and a knotless anchor technique with PE cord. A cyclic (6-N preload; 5-N amplitude; 2-Hz frequency) tensile test (600 cycles) was performed on feline tarsi with either the long or the short medial tarsal ligament intact, with each reconstruction technique followed by a single-cycle load-to-failure test (0.5 mm/s) with a failure point at 2 mm of displacement. Total elongation, peak-to-peak elongation, stiffness, and maximum load to failure point were compared with the intact condition. RESULTS: No differences in stiffness, total elongation, or peak-to-peak elongation were found between specimens repaired with the knotless technique and intact controls (P > .04), whereas tarsi repaired with the tunnel technique and PP were weaker (P < .008). Total and conditioning elongation were greater after tunnel reconstruction with PP than after knotless reconstruction (P = .005). Mean load to 2 mm of displacement tended (P = .03) to be higher after knotless than after knotted PP repairs and did not differ (P = .47) between tarsi repaired with the tunnel or anchor repairs with PE. CONCLUSION: The mechanical properties of intact tarsi were superior to those of tarsi repaired with tunnel techniques and PP but were similar to those of tarsi repaired with knotless techniques with PE. CLINICAL SIGNIFICANCE: Feline tarsal stabilization with the knotless technique for tarsal medial collateral ligament insufficiency may reduce the requirement for or duration of postoperative coaptation.

Femorotibial kinematics in dogs treated with tibial plateau leveling osteotomy for cranial cruciate ligament insufficiency: An in vivo fluoroscopic analysis during walking.

OBJECTIVE: To determine the ability of tibial plateau leveling osteotomy (TPLO) to address abnormal femorotibial kinematics caused by cranial cruciate ligament (CCL) rupture during walking in dogs. STUDY DESIGN: Prospective, clinical. ANIMALS: Sixteen dogs (20-40 kg) with unilateral complete CCL rupture. METHODS: Lateral view fluoroscopy was performed during treadmill walking preoperatively and 6 months after TPLO. Digital three-dimensional (3D) models of the femora and tibiae were created from computed tomographic (CT) images. Gait cycles were analyzed by using a 3D-to-2D image registration process. Craniocaudal translation, internal/external rotation, and flexion/extension of the femorotibial joint were compared between preoperative and 6-month postoperative time points for the affected stifle and 6-month postoperative unaffected contralateral (control) stifles. RESULTS: In the overall population, CCL rupture resulted in 10 ± 2.2 mm (mean ± SD) cranial tibial translation at midstance phase, which was converted to 2.1 ± 4.3 mm caudal tibial translation after TPLO. However, five of 16 TPLO-treated stifles had 4.1 ± 0.3 mm of cranial tibial subluxation during mid-to-late stance phase, whereas 10 of 16 TPLO-treated stifles had 4.3 ± 0.4 mm of caudal tibial subluxation throughout the gait cycle. Overall, postoperative axial rotational and flexion/extension patterns were not different from control, but stifles with caudal tibial subluxation had more external tibial rotation during mid-to-late stance phase compared with stifles with cranial tibial subluxation. CONCLUSION: TPLO mitigated abnormal femorotibial kinematics but did not restore kinematics to control values in 15 of 16 dogs during walking. CLINICAL SIGNIFICANCE: Tibial plateau leveling osteotomy reduces cranial tibial subluxation during walking, but persistent instability is common.

Femorotibial kinematics in dogs with cranial cruciate ligament insufficiency: a three-dimensional in-vivo fluoroscopic analysis during walking.

BACKGROUND: Cranial cruciate ligament (CrCL) insufficiency is a degenerative condition that is a common cause of pelvic limb lameness and osteoarthritis in dogs. Surgical therapies developed to treat dogs with naturally occurring CrCL insufficiency aim to address the resultant instability, but the in-vivo alterations in stifle kinematics associated with CrCL insufficiency have not been accurately defined. The objective of this study was to quantify the 3-dimensional femorotibial joint kinematics of dogs with naturally occurring cranial cruciate ligament (CrCL) insufficiency during ambulation. Eighteen client-owned dogs (20-40 kg) with natural unilateral complete CrCL rupture were included. Computed tomographic scans were used to create digital 3-dimensional models of the femur and tibia bilaterally for each dog. Lateral fluoroscopic images were obtained during treadmill walking and 3 complete gait cycles were analyzed. Stifle flexion/extension angle, craniocaudal translation, and internal/external rotation were calculated throughout the gait cycle using a previously described 3D-to-2D image registration process. Results were compared between the pre-operative CrCL-deficient and 6-month post-operative contralateral stifles (control). RESULTS: CrCL-deficient stifles were maintained in greater flexion throughout the gait cycle. Cranial tibial subluxation was evident in CrCL-deficient stifles at all time points throughout the gait cycle [9.7 mm at mid-stance (P < 0.0001); 2.1 mm at mid-swing (P < 0.0017)], and the magnitude of cranial tibial subluxation was greater at mid-stance phase than at mid-swing phase (P < 0.0001). Greater internal tibial rotation was present in CrCL-deficient stifles during stance phase (P < 0.0022) but no difference in axial rotation was evident during swing phase. CONCLUSIONS: Naturally occurring CrCL rupture causes profound craniocaudal translational and axial rotational instability, which is most pronounced during the stance phase of gait. Surgical stabilization techniques should aim to resolve both craniocaudal subluxation and axial rotational instability.

Quantifying meniscal kinematics in dogs.

The dog has been used extensively as an experimental model to study meniscal treatments such as meniscectomy, meniscal repair, transplantation, and regeneration. However, there is very little information on meniscal kinematics in the dog. This study used MR imaging to quantify in vitro meniscal kinematics in loaded dog knees in four distinct poses: extension, flexion, internal, and external rotation. A new method was used to track the meniscal poses along the convex and posteriorly tilted tibial plateau. Meniscal displacements were large, displacing 13.5 and 13.7 mm posteriorly on average for the lateral and medial menisci during flexion (p = 0.90). The medial anterior horn and lateral posterior horns were the most mobile structures, showing average translations of 15.9 and 15.1 mm, respectively. Canine menisci are highly mobile and exhibit movements that correlate closely with the relative tibiofemoral positions. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1710-1716, 2018.

Kinematics of monoblock bicompartmental knee arthroplasty during weight-bearing activities.

PURPOSE: There is an increased interest in treating arthritis of the medial and patellofemoral compartments without using a total knee arthroplasty. The purpose of this study was to measure kinematics in knees with a monoblock bicompartmental arthroplasty to see whether maintaining the cruciate ligaments and lateral compartment resulted in consistent kinematics more similar to healthy knees than those observed in replaced knees. METHODS: The kinematics of ten knees with monoblock bicompartmental arthroplasty were observed using fluoroscopy during three weight-bearing activities. Model-image registration techniques were used to quantify the three-dimensional motions of the knee joints. RESULTS: During kneeling, lunging, and stair-step activities, the medial condyle remained relatively close to the centre of the tibial plateau, while the lateral condyle typically moved posteriorly with flexion. Knees generally exhibited motion patterns consistent with retained cruciate ligament function, but individual patterns varied significantly. CONCLUSIONS: Bicompartmental knee arthroplasty has the potential to retain more natural knee function. Improved tools for aligning the implants and increased implant sizing options may be required to achieve highly consistent results and realize the clinical benefit of a knee arthroplasty with intact cruciate ligaments. LEVEL OF EVIDENCE: III.

Accuracy of dynamic tactile-guided unicompartmental knee arthroplasty.

Unicompartmental knee arthroplasty (UKA) can achieve excellent clinical and functional results for patients having single-compartment osteoarthritis. However, UKA is considered to be technically challenging to perform, and malalignment of implant components significantly contributes to UKA failures. It has been shown that surgical navigation and tactile robotics could be used to provide very accurate component placement when the bones were rigidly fixed in a stereotactic frame during preparation. The purpose of this investigation was to determine the clinically realized accuracy of UKA component placement using surgical navigation and tactile robotics when the bones are free to move. A group of 20 knees receiving medial UKA with dynamically referenced tactile-robotic assistance was studied. Implant placement errors were comparable with those achieved using tactile robotics with rigid stereotactic fixation.