CaCl2-Citrate Regional Anticoagulation with Continuous Veno-Venous Haemodialysis Leads to Unwanted Chloride Loading Compared to Continuous Veno-Venous Hemofiltration with Systemic Anticoagulation.

INTRODUCTION: Chloride transfers during continuous renal replacement therapy (CRRT) have not been adequately described and may differ based on CRRT technique. We aimed to measure chloride mass transfer (JS,Cl) during CRRT and identify associated determinants. METHODS: We performed a two-centre, prospective, observational study in France and Australia in ICU patients with CRRT initiated for <24 h. Patients received continuous veno-venous hemofiltration (CVVH) or continuous veno-venous haemodialysis (CVVHD, with citrate-CaCl2 regional anticoagulation). Over a 24 h period, plasma and effluent chloride concentrations were measured every 4 h to compute chloride mass transfer (JS,Cl, in mmol.min-1) using a modality-specific model, with negative value indicating chloride transfer towards the patient. Secondary outcomes were the identification of CRRT settings associated with JS,Cl (using multivariate mixed effects regression). Results are presented with median (interquartile range). RESULTS: Between February 2021 and August 2022, we enrolled 37 patients (64 [56-71] years, 67% male), for a total of 20 CVVHD and 20 CVVH sessions. Over 24 h, plasma chloride concentrations were significantly higher, and JS,Cl significantly lower during CVVHD, compared to CVVH (-0.10 [-0.33 to 0.15] vs. 0.01 [-0.10 to 0.13] mmol.min-1, p < 0.05). With both modalities, net ultrafiltration (QUFNET) and plasma chloride concentrations were the principal determinants of JS,Cl, with higher QUFNET being associated with an increase in JS,Cl during CVVHD. Also, CVVHD sessions demonstrated a concentration gradient between the plasma and the effluent chamber of -6 [-9 to -4] mmol.L-1. Finally, CaCl2 reinjection during CVVHD accounted for 35% [32-60%] of total JS,Cl in sessions with a negative JS,Cl. CONCLUSION: Compared to CVVH, CVVHD with regional citrate anticoagulation was associated with greater chloride mass transfer to the patient and higher plasma chloride concentrations. This was due to high dialysate chloride concentrations and CaCl2 reinjection. This effect could only be controlled by high net ultrafiltration flow rates.

Exploration of COVID-19 associated bradycardia using heart rate variability analysis in a case-control study of ARDS patients.

BACKGROUND: Bradycardia and dysautonomia observed during SARS-Cov2 infection suggests involvement of the autonomic nervous system (ANS). Limited data exists on ANS dysregulation and its association with outcomes in patients with acute respiratory distress syndrome (ARDS) related to COVID-19 (C-ARDS) or other etiologies (NC-ARDS). OBJECTIVES: We aimed to explore sympathovagal balance, assessed by heart rate variability (HRV), and its clinical prognostic value in C-ARDS compared with NC-ARDS. METHODS: A single-center, prospective case-control study was conducted. Consecutive patients meeting ARDS criteria between 2020 and 2022 were included. HRV was assessed using 1-hour electrographic tracing during a stable, daytime period. RESULTS: Twenty-four patients with C-ARDS and 19 with NC-ARDS were included. Age, sex and ARDS severity were similar between groups. The median heart rate was markedly lower in the C-ARDS group than in the NC-ARDS group (60 [53-72] versus 101 [91-112] bpm, p<.001). Most of HRV parameters were significantly increased in patients with C-ARDS. HRV correlated with heart rate only in patients with C-ARDS. A positive correlation was found between the low-to high-frequency ratio (LF/HF) and length of intensive care unit stay (r = 0.576, p<.001). CONCLUSION: This study confirmed that C-ARDS was associated with marked bradycardia and severe ANS impairment, suggesting a sympathovagal imbalance with vagal overtone. Poor outcomes appeared to be more related to sympathetic rather than parasympathetic hyperactivation.

Mid-term results of total elbow arthroplasties in the treatment of geriatric distal humerus fractures.

BACKGROUND: While double plate fixation is the gold standard treatment for distal humerus fractures in the general population, it is the source of many complications in the elderly. Total elbow arthroplasty (TEA) has been proposed as an alternative treatment, with satisfactory short-term functional outcomes. However, little is known about the longevity of the implant and the mid- and long-term complications of this procedure. MATERIALS AND METHODS: A total of 58 TEAs were performed in 57 patients with comminuted distal humerus fractures between September 2008 and September 2019. All patients were clinically (ranges of motion, Mayo Elbow Performance Score [MEPS] and Disabilities of the Arm, Shoulder and Hand [QuickDASH] functional scores) and radiographically assessed. The minimum follow-up was 2years, and the mean follow-up was 4.7years. RESULTS: The overall complication rate was 20.7%, with ulnar nerve damage, complex regional pain syndrome, and severe stiffness being the main complications. The mean MEPS was 85.3, and the mean QuickDASH was 28.1. The mean flexion was 122°, and the mean extension was -23.5°. There were no prosthetic revisions. Of these patients, 17% had radiolucent lines, and 13% had bushing wear at the last follow-up. DISCUSSION: TEA is an effective technique for treating comminuted distal humerus fractures in the geriatric population. The prosthesis's mid-term survivorship was highly satisfactory, with a complication rate that remained low and was generally lower than that of osteosynthesis, with identical functional outcomes. TEAs are indicated in elderly patients, for whom maintaining the fullest possible autonomy is paramount. Our findings suggest that TEAs have sufficient longevity to guarantee a functional, pain-free elbow with no need for reoperation. LEVEL OF EVIDENCE: IV; case series.

Determinants of Urine Output Using Advanced Hemodynamic Monitoring in Critically Ill Patients Undergoing Continuous Renal Replacement Therapy.

INTRODUCTION: Low cardiac output and hypovolemia are candidate macrocirculatory mechanisms explanatory of de novo anuria in intensive care unit (ICU) patients undergoing continuous renal replacement therapy (CRRT). We aimed to determine the hemodynamic parameters and CRRT settings associated with the longitudinal course of UO during CRRT. METHODS: This is an ancillary analysis of the PRELOAD CRRT observational, single-center study (NCT03139123). Enrolled adult patients had severe acute kidney injury treated with CRRT for less than 24 h and were monitored with a calibrated continuous cardiac output monitoring device. Hemodynamics (including stroke volume index [SVI] and preload-dependence, identified by continuous cardiac index variation during postural maneuvers), net ultrafiltration (UFNET), and UO were reported 4-hourly, over 7 days. Two study groups were defined at inclusion: non-anuric participants if the cumulative 24 h UO at inclusion was ≥0.05 mL kg-1 h-1, and anuric otherwise. Quantitative data were reported by its median [interquartile range]. RESULTS: Forty-two patients (age 68 [58-76] years) were enrolled. At inclusion, 32 patients (76%) were not anuric. During follow-up, UO decreased significantly in non-anuric patients, with 25/32 (78%) progressing to anuria within 19 [10-50] hours. Mean arterial pressure (MAP) and UFNET did not significantly differ between study groups during follow-up, while SVI and preload-dependence were significantly associated with the interaction of study group and time since inclusion. Higher UFNET flow rates were significantly associated with higher systemic vascular resistances and lower cardiac output during follow-up. Multivariate analyses showed that (1) lower UO was significantly associated with lower SVI, lower MAP, and preload-independence; and (2) higher UFNET was significantly associated with lower UO. CONCLUSIONS: In ICU patients treated with CRRT, those without anuria showed a rapid loss of diuresis after CRRT initiation. Hemodynamic indicators of renal perfusion and effective volemia were the principal determinants of UO during follow-up, in relation with the hemodynamic impact of UFNET setting.

Pyrolytic carbon head shoulder arthroplasty: CT scan glenoid bone modeling assessment and clinical results at 3-year follow-up.

Background: The aim of this study is to report the radiological glenoid modifications and clinical outcomes at 3 years mean follow-up of hemi shoulder arthroplasty (HA) with pyrocarbon (PYC) humeral head. Our hypothesis was that the PYC implants would provide good outcomes without major glenoid erosion. Additionally, we hypothesized that HA-PYC allowed for remodeling of the bone. Methods: Patients underwent HA with PyC humeral head for treatment of primary or secondary osteoarthritis, excluding post-traumatic cases. All patients had a Constant Score assessed preoperatively and at the last follow-up. Preoperative and postoperative computed tomography scans at the last follow-up were performed to achieve 3-dimensional reconstructions of the scapulae. Deformities of the glenoid surface were analyzed as a distance differential between postoperative and preoperative to investigate potential bone remodeling vs. glenoid erosion. The subluxation index (SLI) was measured. Results: We included 41 patients implanted with a HA-PYC. Average age at the time of implant was 63.8 (40 to 79 years). All patients were followed for ≥2 years with an average follow-up of 36.3 months (24 to 60 months). Constant Scores increased from 34 at baseline to 80 at the last follow-up points on average (P < .01). Return to work rate was 100% and 96% had resumed their physical activity. Ten (77%) of the 13 patients with posterior head subluxation had normalized their SLI. Furthermore, no significant differences were detected between the individuals having corrected their posterior subluxation and the others (preoperative SLI between 0.45 and 0.55). Glenoid wear is less than 0.6 mm at 3 years mean follow-up, ie, 5 times less than metallic implants. A tendency to recenter the head in the anteroposterior plane was found in type B glenoid, without increased erosion of the glenoid, with very good clinical results. We did not find any difference according to age or glenoid type for clinical and radiological results. Conclusion: HA-PYCs give, in the short term, excellent clinical results in terms of pain and function. The development of a precise and objective measurement method has made it possible to demonstrate that the glenoid surface is the site of modifications that may be part of bone remodeling or progression of the osteoarthritis disease.

Every layer of quadriceps tendon's central and medial portion offers similar tensile properties than Hamstrings or Ilio-Tibial Band Grafts.

PURPOSE: The aim of our cadaveric study was to compare the mechanical properties of different parts of the quadriceps' tendon in a load to failure analysis as compared to three other, and most common types of grafts that are used to perform ligament's reconstruction. METHODS: Ten fresh-frozen cadavers (5 women, 5 men) were selected from our anatomical department. Mean age at death was 64 years (48-87 years). Tendons were harvested to prepare (1) different quadriceps tendon's specimens: lateral portion (QTlat), medial portion superficial layer (QTMsup) and deep layer (QTMdeep) and central portion superficial (QTCsup) and deep layers (QTCdeep) (2) Patellar Tendon (PT), (3) Gracilis+Semi-Tendinosus specimens (GST). Specimens were stored at - 40 °C in a freezing solution. Specimens were securely attached to a dedicated loading platform, measurements were done using a validated software. Load to failure testing was then carried out. Young's Elastic moduli, ultimate Stress (MPa) and Deformation (%) were analysed. RESULTS: The elastic moduli of the PT was significantly higher than all other grafts, all medial and central QT layers (superficial and deep) were significantly higher than its lateral part (QTlat). In terms of Ultimate Stress, all grafts were significantly greater than QTlat, PT and GST were significantly superior to QT central portions and to ITB but there did not differ with the medial portion of QT. ITB ultimate stress values were significantly higher than QTlat. The ultimate deformations of all grafts were similar. CONCLUSIONS: This study provides reference values in in order to characterize different parts of the QT that presents anatomically and Mechanically with complex characteristics. Every Layer of Quadriceps Tendon's Central and Medial Portion Offered Similar Mechanical Properties than Two Strand Hamstrings or Ilio-Tibial Band.

Analysis of parameters influencing intraarticular temperature during radiofrequency use in shoulder arthroscopy.

PURPOSE: The aim of this study was to analyze the influence of several factors on the temperature in the work chamber during shoulder arthroscopy procedures in order to identify danger zones when using radiofrequency. METHODS: Intraarticular temperature was measured intraoperatively using system with special probe that directly measured the temperature in 22 patients. Data collection was prospective. The main parameters studied were the measurement of the temperature depending on: localization of the procedure (glenohumeral or subacromial), the use of coagulation or ablation, the number of portals, the pressure of the arthropump, the time of use, the blood pressure and the temperature of the operating room. RESULTS: Ninety-three recordings were made. No complications were identified. Addition of a portal reduces the average elevation of 3.8 °C (p < 0.05). Ambient temperature above 19.15 °C with two portals leads to an average increase of 13.3 °C (p < 0.05). Increasing the pressure of the arthropump of 10 mmHg increases the temperature of 0.8 °C (p < 0.05). No significant difference was found on the change in blood pressure, location and mode of use. CONCLUSIONS: These results show the interest of controlling these factors when performing shoulder arthroscopy procedure. This study identifies situations of high joint risk when using radiofrequency and thus to prevent secondary complications such as burns and massive chondrolyses.

Three- and four-part displaced proximal humeral fractures in patients older than 70 years: reverse shoulder arthroplasty or nonsurgical treatment?

BACKGROUND: The objective of our study was to evaluate the results of surgical treatment by reverse shoulder arthroplasty (RSA) compared with nonsurgical treatment after 2 years of follow-up in patients aged 70 years or older with displaced 3-part or 4-part proximal humeral fractures. METHODS: Two groups were formed: the RSA group (n = 28) and the nonsurgical group (n = 32). Minimum follow-up was 2 years. We included patients with 3-part or 4-part fractures according to the Neer classification. Main outcome measures were the Constant-Murley score, the 11-item version of the Disabilities of the Arm, Shoulder and Hand score, and the Subjective Shoulder Value score. An autonomy score, a cognitive assessment score, and a pain score were also measured. RESULTS: Clinical features in the 2 groups were not significantly different. The Constant-Murley mean score was significantly higher for the RSA group (82.1% vs. 76.8%; P = .03). Amplitudes were all higher in favor of the RSA group (P < .02). There was no significant difference in mean score on the 11-item version of the Disabilities of the Arm, Shoulder and Hand score, the preoperative and postoperative Subjective Shoulder Value score, the autonomy score, the cognitive assessment score, or the pain score in both groups at the last follow-up. The complication rate was higher for the RSA group. CONCLUSIONS: These results suggest that RSA treatment of proximal humeral fractures with 3-part or 4-part displaced fragments in elderly patients provides better functional outcomes than does nonsurgical treatment. However, the observed clinical difference was relatively small. This solution must be proposed only to patients who have a significant functional demand.