Cannula Size Research Articles

A risk prediction model for adult patients with difficult intravenous access.

The challenges posed by difficult intravenous access (DIVA) in clinical treatment are not only related to technical difficulties but also have the potential to affect the quality of patient care and overall experience. It is crucial to adopt effective strategies to address difficult intravenous access. Currently, the assessment of difficult veins largely relies on individual perception and experience, which introduces a significant degree of subjectivity. To develop and validate a risk prediction model for DIVA in adult patients, providing a tool for early identification and intervention. An observational study. Retrospective data collection was conducted on 1170 hospitalized patients who required the placement of a short peripheral venous catheter for treatment in a tertiary hospital from June 1, 2022, to September 30, 2022, as the training set. Logistic regression analysis was employed to identify factors influencing DIVA in adult patients and to construct a risk prediction model. Prospective data collection was conducted on 300 hospitalized patients from June 1, 2023, to June 30, 2023, for external validation. The discriminative ability, calibration, and clinical utility of the model were evaluated using the area under the receiver operating characteristic curve, calibration curve, and clinical decision curve, respectively. A TRIPOD checklist was used to guide the reporting of this study. The average age of patients in the training set was 58.60 ± 15.39 years. Among them, 626 were males (53.50%) and 544 were females (46.50%). The external validation group included a total of 300 patients with a mean age of 58.77 ± 15.26 years. There were 142 males (47.33%) and 158 females (52.67%). Advanced age, female sex, extreme weight (BMI <18.5 or >30), history of hemodialysis, axillary lymph node dissection for breast cancer, compromised skin integrity, history of DIVA, and target cannula size ⩽20G are independent predictive factors for DIVA in adult patients (all p < 0.05). The risk prediction model constructed based on these factors had an area under the ROC curve of 0.912 (95% CI 0.880-0.943) in the modeling group. The areas under the ROC curve in the internal and external validation groups were 0.887 (95% CI 0.855-0.924) and 0.870 (95% CI 0.799-0.942), respectively. Calibration curves showed good agreement between predicted and observed probabilities. Decision curve analysis demonstrated that intervening when the risk of venous puncture difficulty ranged from 3% to 91% yielded favorable clinical benefits for patients. Constructing a risk prediction model for DIVA in adult patients has significant predictive value. It assists medical staff in early intervention and management for high-risk patients, thereby achieving effective prediction, warning, and control.

Association Between Cannula Size of Extracorporeal Membrane Oxygenation and Prognosis in Patients With Out-of-Hospital Cardiac Arrest ― A Secondary Analysis of the SAVE-J II Study ―

Selecting an appropriate cannula size is crucial for achieving an adequate extracorporeal membrane oxygenation (ECMO) flow rate. However, the association between ECMO cannula size and the prognosis of patients with out-of-hospital cardiac arrest (OHCA) has not been fully elucidated. We examined the associations between ECMO cannula size and neurological outcomes and survival at discharge in patients with OHCA who received ECMO. This is a secondary analysis of the Study of Advanced life support for Ventricular fibrillation with Extracorporeal circulation in Japan (SAVE-J II study). The primary and secondary outcomes were favorable neurological outcomes and survival at discharge, respectively. In all, 918 patients were included in the analysis. There were no statistically significant differences between cannula sizes and neurological outcomes. Multivariable analysis showed that increasing body weight (BW)-adjusted sizes of arterial cannulas (odds ratio [OR] 1.04 per 0.01-Fr/kg increase; 95% confidence interval [CI] 1.01-1.07; P=0.011) and venous cannulas (OR 1.04 per 0.01-Fr/kg increase; 95% CI 1.01-1.06; P=0.005) were significantly associated with the survival rate at discharge. Increasing BW-adjusted sizes of arterial cannulas were significantly associated with cannulation site bleeding. There were no significant associations between favorable neurological outcomes and cannula size, whereas larger-sized arterial and venous cannulas were significantly associated with higher survival rates at discharge in patients with OHCA who received ECMO.

Acute Limb Ischemia in Patients on Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support: A Ten-Year Single-Center Experience

ObjectivesVA-ECMO has been increasingly utilized as a life-saving modality in patients with cardiopulmonary compromise. Acute limb ischemia (ALI) has been reported when the femoral artery was accessed, and it was associated with higher mortality in patients on ECMO. However, prior studies were limited by small sample size and the lack of long-term follow-up. We aimed to investigate the predictors of ALI in ECMO and the effect of ALI on long-term mortality. MethodsRetrospective institutional chart review was performed. Patients who underwent VA-ECMO (Jan/2008-Jan/2018) were identified. Primary outcomes were ALI and 4-year mortality. Logistic regression analysis was used to investigate the predictors of ALI. Survival analysis methods were used to examine 4-year mortality. ResultsA total of 377 patients were included. Vascular complications took place in 149 (39.5%) patients. The majority was ALI (107, 75.4%). Eleven patients had limb loss. ALI patients were younger (mean age: 50.2±15.9 vs 54.1±15.5; p=.03), were more likely to have history of PAD (7.6%vs 3.0%; p=.047), were less likely to be on aspirin (40.2% vs 54.4%; p=.013) and were more likely to be on vasopressors (97.1% vs 88.0%; p=.007). Arterial cannula size was not associated with ALI so as the concurrent use of ventricular offloading devices (intra-aortic balloon pump or Impella (Abiomed Inc, Dancers, MA)). The use of distal perfusion catheter (DPC) was not protective against ALI in this cohort. However, DPC was associated with less likelihood to require vascular intervention (20.1% vs 32.0%; p=.009). In adjusted analysis, aspirin use was protective against ALI [adjusted odds ratios (aOR) 95%CI: 0.52(0.30-0.90); p=.018]. The only predictor of ALI was the use of vasopressors [aOR(95%CI): 6.8 (1.5-30.4); p=.012]. For those who were successfully decannulated, four-year survival was 65.1% in patients without ALI vs 46.8% in ALI (p=0.044). After adjusting for potential risk factors, 4-year mortality hazard was significantly higher in patients with ALI [HR: 1.80(1.04-3.12); p=.035]. ConclusionsPatients requiring ECMO are critically ill. The development of acute limb ischemia is detrimental to this population. This effect extends beyond the acute period. ALI increased 4-year mortality risk by 80%. Use of DPC did not protect against ALI but it was associated with less vascular interventions.

The impact of different prong-nares ratio on ventilation in COPD patients using nasal high-flow (NHF) – a physiological study

IntroductionNasal high flow (NHF) is a popular technique to provide support in respiratory failure in different conditions. Recently published bench studies have hypothesized that airway pressure can be increased by using different cannula sizes and corresponding prongs resulting in a range of prong-nare ratios. We conducted this study to verify these experimental findings in clinical practice.MethodsWe characterized prong size and flow rate dependent changes in ventilation parameters and changes in hypercapnia in an interventional clinical setting. Outcome parameters included changes in mean airway pressure, tidal volume (TV), respiratory rate (RR), minute volume (MV) and decrease in pCO2. The ventilatory parameters were determined at 20, 30, 40 and 50 l/min with 3 different prong sizes. 20 and 40 l/min and the 3 different prong sizes were used to document the changes in pCO2.ResultsIn this study we demonstrate changes in ventilation with increasing flow rates of NHF. A significant increase in mean airway pressure was seen with every 10 l/min increase in flow rate. Respiratory rate and minute volume (using large prongs) changed significantly with larger increases in flow rate, while tidal volume was not significantly altered. When the flow rate was increased by 20 l/min (i.e. from 20 l/min to 40 l/min) capillary pCO2 decreased significantly. None of the measured values were significantly altered by the prong size used.ConclusionIn summary, we presented strong indications that different prong sizes have no influence on essential respiratory parameters or the elimination of pCO2 when using NHF in COPD patients.

Efficacy and safety of percutaneous post-closure technique during the decannulation for veno-arterial extracorporeal membrane oxygenation.

In recent years, during the decannulation process for veno-arterial extracorporeal membrane oxygenation (VA-ECMO), methods for suturing the femoral artery have included the pre- and post-closure techniques. The safety and efficacy of the pre-closure technique are widely recognised; however, reports on the post-closure technique are scarce. This study aimed to evaluate the safety and efficacy of the post-closure technique using ProGlide (Abbott Healthcare, Green Oaks, IL, USA) device during VA-ECMO decannulation. We reviewed 170 patients who underwent VA-ECMO between January 2021 and June 2023. All patients had their femoral artery puncture sites closed using the post-closure technique upon decannulation. The success rate of this technique and incidence of lower limb complications were recorded and analysed. Technical success was achieved in 157 (92.4%) patients. Sixteen patients (9.4%) experienced lower limb-related complications, including 8 (4.7%) with lower limb arterial thrombosis and 11 (6.5%) with pseudo-aneurysms. Among all lower limb-related complications, four patients (2.4%) required interventional procedures. This study included 170 patients: 80 in the 'S' (15-16F) group and 90 in the 'M' (17-19F) group. In the univariate analysis of different arterial cannula sizes for in-hospital lower limb-related complications, the differences were not statistically significant (p > 0.05). The multivariate logistic model indicated that, compared to the S (15-16F) group, the M (17-19F) group was not associated with an increased rate of in-hospital lower limb-related complications. The suture-mediated closure of the femoral artery during VA-ECMO decannulation is a promising therapeutic strategy.

Does cannula's size alter rheological properties of hyaluronic acid filler?

This study evaluated the rheological properties of various hyaluronic acid (HA) gels after passing through different-sized cannulas (22-G and 25-G). Five commercial brands of highly crosslinked HA fillers were analyzed: (A) Rennova® Ultra Deep, (B) Restylane® Lyft, (C) Hialurox® - Ultra Lift, (D) Belotero® Volume, and (E) E.P.T.Q S500. Rheological characterization was conducted using an automated controlled stress rheometer. The rheological properties of the fillers were assessed both before and after passing through the cannulas. Each filler brand and cannula size was tested three times by a researcher who was blinded to the commercial brands. For data analysis, frequencies of 0.1, 0.5, and 2 Hz were employed. The rheological properties (storage modulus [G'] and loss modulus [G"]) of the high-crosslink HA fillers did not change after being passed through cannulas of different sizes (22-G and 25-G) (p > 0.109) compared to baseline measurements (no cannula). Furthermore, all fillers displayed desirable solid-like, volumizing behavior at low frequencies and strain amplitudes (<10 %). Under physiologically relevant conditions for skin and facial applications, the cannula size did not alter the rheological properties of high crosslink HA fillers.

Vascular Complications in Extracorporeal Membrane Oxygenation-A Narrative Review.

The establishment of a peripheral ECMO circuit can lead to significant arterial and venous complications in 10-30% of patients. Vascular complications, particularly acute limb ischemia, are associated with worsening overall outcomes. Limb ischemia occurs significantly more frequently in the early stages of VA ECMO than in VV ECMO. Mechanisms of limb ischemia include arterial obstruction, cannulation injury, loss of pulsatile flow, thromboembolism, venous stasis from compressive obstruction with large venous cannulas, and systemic vasoconstriction due to shock and pharmacologic vasoconstriction. The care team may use several mitigation strategies to prevent limb ischemia. Arterial and venous complications can be mitigated by careful access site selection, minimizing cannula size, placement of distal perfusion and/or outflow catheter(s), and continuous NIRS monitoring. Rapid intervention, when ischemia or compartment syndrome occurs, can reduce limb loss but may not affect the mortality and morbidity of the ECMO patient in the long term due to their underlying conditions and the etiology of the ECMO need.

Flow capabilities of arterial and drainage cannulae during venoarterial extracorporeal membrane oxygenation: A simulation model.

Large cannulae can increase cannula-related complications during venoarterial extracorporeal membrane oxygenation (VA ECMO). Conversely, the ability for small cannulae to provide adequate support is poorly understood. Therefore, we aimed to evaluate a range of cannula sizes and VA ECMO flow rates in a simulated patient under various disease states. Arterial cannulae sizes between 13 and 21 Fr and drainage cannula sizes between 21 and 25 Fr were tested in a VA ECMO circuit connected to a mock circulation loop simulating a patient with severe left ventricular failure. Systemic and pulmonary hypertension, physiologically normal, and hypotension were simulated by varying systemic and pulmonary vascular resistances (SVR and PVR, respectively). All cannula combinations were evaluated against all combinations of SVR, PVR, and VA ECMO flow rates. A 15 Fr arterial cannula combined with a 21 Fr drainage cannula could provide >4L/min of total flow and a mean arterial pressure of 81.1 mmHg. Changes in SVR produced marked changes to all measured parameters, while changes to PVR had minimal effect. Larger drainage cannulae only increased maximum circuit flow rates when combined with larger arterial cannulae. Smaller cannulae and lower flow rates could sufficiently support the simulated patient under various disease states. We found arterial cannula size and SVR to be key factors in determining the flow-delivering capabilities for any given VA ECMO circuit. Overall, our results challenge the notion that larger cannulae and high flows must be used to achieve adequate ECMO support.

Performance Characterisation of the Airvo2TM Nebuliser Adapter in Combination with the Aerogen SoloTM Vibrating Mesh Nebuliser for in Line Aerosol Therapy during High Flow Nasal Oxygen Therapy.

High flow oxygen (HFO) therapy is a well-established treatment in respiratory disease. Concurrent aerosol delivery can greatly expediate their recovery. The aim of this work was to complete a comprehensive characterisation of one such HFO therapy system, the Airvo2TM, used in combination with the Aerogen SoloTM vibrating mesh nebuliser. Representative adult, infant, and paediatric head models were connected to a breathing simulator via a collection filter placed at the level of the trachea. A tracheostomy interface and nasal cannulas were used to deliver the aerosol. Cannula size and gas flow rate were varied across the full operating range recommended by the manufacturer. The tracheal and emitted doses were quantified via UV-spectrophotometry. The aerosol droplet diameter at the exit of the nares and tracheal interface was measured via cascade impaction. High gas flow rates resulted in low emitted and tracheal doses (%). Nasal cannula size had no significant effect on the tracheal dose (%) available in infant and paediatric models. Higher gas flow rates resulted in smaller aerosol droplets at the exit of the nares and tracheostomy interface. Gas flow rate was found to be the primary parameter affecting aerosol delivery. Thus, gas flow rates should be kept low and where possible, delivered using larger nasal cannulas to maximise aerosol delivery.

Alternative venous access sites for dual-lumen extracorporeal membrane oxygenation cannulation.

Dual-lumen cannulas for veno-venous (VV) extracorporeal membrane oxygenation (ECMO) support are typically inserted in the right internal jugular vein (RIJV); however, some scenarios can make this venous route inaccessible. This multicentre case series aims to evaluate if single-site cannulation using an alternative venous access is safe and feasible in patients with an inaccessible RIJV. We performed a multi-institutional retrospective analysis including high-volume ECMO centres with substantial experience in dual-lumen cannulation (DLC) (defined as >10 DLC per year). Three centres [Freiburg (Germany), Toronto (Canada) and Vienna (Austria)] agreed to share their data, including baseline characteristics, technical ECMO and cannulation data as well as complications related to ECMO cannulation and outcome. A total of 20 patients received alternative DLC for respiratory failure. Cannula insertion sites included the left internal jugular vein (n = 5), the right (n = 7) or left (n = 3) subclavian vein and the right (n = 4) or left (n = 1) femoral vein. The median cannula size was 26 (19-28) French. The median initial target ECMO flow was 2.9 (1.8-3.1) l/min and corresponded with used cannula size and estimated cardiac output. No procedural complications were reported during cannulation and median ECMO runtime was 15 (9-22) days. Ten patients were successfully bridged to lung transplantation (n = 5) or lung recovery (n = 5). Ten patients died during or after ECMO support. Alternative venous access sites for single-site dual-lumen catheters are a safe and feasible option to provide veno-venous ECMO support to patients with inaccessible RIJV.

Blood flow and emboli transport patterns during venoarterial extracorporeal membrane oxygenation: A computational fluid dynamics study

ProblemDespite advances in Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO), a significant mortality rate persists due to complications. The non-physiological blood flow dynamics of VA-ECMO may lead to neurological complications and organ ischemia. Continuous retrograde high-flow oxygenated blood enters through a return cannula placed in the femoral artery which opposes the pulsatile deoxygenated blood ejected by the left ventricle (LV), which impacts upper body oxygenation and subsequent hyperoxemia. The complications underscore the critical need to comprehend the impact of VA-ECMO support level and return cannula size, as mortality remains a significant concern. AimThe aim of this study is to predict and provide insights into the complications associated with VA-ECMO using computational fluid dynamics (CFD) simulations. These complications will be assessed by characterising blood flow and emboli transport patterns through a comprehensive analysis of the influence of VA-ECMO support levels and arterial return cannula sizes. MethodsPatient-specific 3D aortic and major branch models, derived from a male patient's CT scan during VA-ECMO undergoing respiratory dysfunction, were analyzed using CFD. The investigation employed species transport and discrete particle tracking models to study ECMO blood (oxygenated) mixing with LV blood (deoxygenated) and to trace emboli transport patterns from potential sources (circuit, LV, and aorta wall). Two cannula sizes (15 Fr and 19 Fr) were tested alongside varying ECMO pump flow rates (50%, 70%, and 90% of the total cardiac output). ResultsCannula size did not significantly affect oxygen transport. At 90% VA-ECMO support, all arteries distal to the aortic arch achieved 100% oxygen saturation. As support level decreased, oxygen transport to the upper body also decreased to a minimum saturation of 73%. Emboli transport varied substantially between emboli origin and VAECMO support level, with the highest risk of cerebral emboli coming from the LV with a 15 Fr cannula at 90% support. ConclusionArterial return cannula sizing minimally impacted blood oxygen distribution; however, it did influence the distribution of emboli released from the circuit and aortic wall. Notably, it was the support level alone that significantly affected the mixing zone of VA-ECMO and cardiac blood, subsequently influencing the risk of embolization of the cardiogenic source and oxygenation levels across various arterial branches.

Cannula to Femoral Artery Diameter Ratio Predicts Potential Lower-Limb Ischemia in Minimally Invasive Cardiac Surgery With Femoral Cannulation.

Lower-limb ischemia is a complication of minimally invasive cardiac surgery with femoral cannulation. Herein, we verified our strategy using distal perfusion cannulation (DPC) against this complication. We retrospectively assessed 91 cases of aortic valve replacement with femoral cannulation between January 2019 and March 2023. DPC was applied when lower-limb tissue oxygenation index declined by ≥20%. The cannula to femoral artery diameter ratio (C/FA) was calculated by dividing the cannula size (Fr) divided by 3 by the femoral artery inner diameter (mm). Postoperative maximum creatinine kinase (CKmax), lactate dehydrogenase (LDHmax), and lactate levels were analyzed, and univariable logistic regression and receiver operating characteristic curve analyses were employed to determine DPC predictors and the cutoff C/FA for DPC, respectively. Patients without DPC were divided into 2 subgroups based on the cutoff C/FA for further comparisons. DPC was required in 9 patients. Symptomatic ischemia was not observed. All laboratory data were similar in the DPC and non-DPC groups. C/FA was significantly associated with DPC (odds ratio = 1.27, 95% confidence interval: 1.09 to 1.47, P = 0.002), and the cutoff C/FA was 0.70 (sensitivity = 0.89, specificity = 0.80). In the non-DPC group, CKmax (P = 0.027) and LDHmax (P = 0.041) were significantly higher in patients with C/FA ≥0.7 (n = 16) than in those with C/FA <0.7 (n = 66). Our strategy for preventing symptomatic ischemia is reasonable and could be almost achieved without DPC when C/FA is <0.7. C/FA also predicts asymptomatic potential ischemia, and proactive DPC is preferable when C/FA is ≥0.7.

Impact of cannula diameter on pregnancy outcomes after minimally invasive fetal laser surgery in the treatment of twin-to-twin transfusion syndrome: A systematic review and meta-analysis.

Preterm prelabor rupture of membranes (PPROM) remains a major complication of fetal laser surgery in the treatment of twin-to-twin transfusion syndrome (TTTS). The aim of the study was to determine the impact of cannula size on pregnancy outcomes, with a particular focus on PPROM. The protocol was developed and registered in the PROSPERO database under registration number CRD42022333630. The PubMed, Web of Science, and EMBASE databases were searched electronically on May 18, 2022, and updated on March 2, 2023, utilizing a combination of the relevant MeSH terms, keywords, and word variants for "TTTS" and "laser". Randomized controlled trials, prospective and retrospective cohorts, case-control studies, and case reports/series with more than five participants were considered eligible for inclusion. Studies reporting the cannula diameter and PPROM rate after laser surgery in the treatment of monochorionic pregnancies affected by TTTS between 16- and 26 weeks' gestation were included. Data was extracted independently, and when appropriate, a random-effects meta-analysis was undertaken to calculate pooled estimates and their confidence intervals. Heterogeneity in the effect estimates of the individual studies was calculated using the I2 statistic. The primary outcome was PPROM rate. Secondary outcomes were survival rate, preterm birth, and incomplete surgery. The quality of the included studies was assessed using a modified quality in prognosis study tool. We included a total of 22 studies, consisting of 3426 patients. Only one study was scored as low quality, seven as moderate quality, and the remaining 14 as high quality. The mean PPROM rate after laser surgery treating TTTS was 22.9%, ranging from 11.6% for 9 French (Fr) to 54.0% for 12 Fr. Subsequent meta-regression for the clinically relevant PPROM rate before 34 weeks of gestation, showed increased PPROM rates for increased cannula size (p-value 0.01). This systematic review confirmed PPROM as a frequent complication of fetal laser surgery, with a mean PPROM rate of 22.9%. A larger cannula diameter relates to a significant higher PPROM risk for PPROM before 34 weeks gestation. Hence, the ideal balance between optimal visualization requiring larger port diameters and shorter operation time and more complete procedures that benefit from larger diameters is crucial to reduce iatrogenic PPROM rates.

Gluteal Fat Grafting Technique and Mortality Update Among Surveyed ABCS Surgeons

Background: The demand for gluteal fat grafting (colloquially known as Brazilian butt lift [BBL]) has seen a dramatic increase in the past decade. Brazilian butt lift has been the fastest-growing cosmetic procedure in the United States for several years. During this time, the incidence of pulmonary fat embolisms (PFEs) associated with this procedure has raised safety concerns. Several professional organizations have responded to these concerns with investigational reports to identify the causes and provide recommendations to decrease the mortality associated with this popular cosmetic procedure. Awareness and implementation of these safety recommendations have been a cornerstone to decreasing the mortality rate associated with gluteal fat grafting. Objectives: To provide a comparison of current technical approaches and a mortality update on gluteal fat grafting among surgical members from the American Board of Cosmetic Surgeons (ABCS) within the last 6 years. Also, to determine if specific technical changes in the manner this procedure is performed are improving safety. Methods: An online (emailed) survey regarding perioperative gluteal fat grafting techniques and postoperative outcomes performed by ABCS surgeons within the previous 3 years was collected in 2 different 3-year time frames. Initial data were collected in 2019 for the preceding 3 years 2016-2019. The survey was again repeated in 2022 to collect similar data as before from ABCS member years 2019-2021. The data, which included the total # of BBLs performed, incidence of major infection or fat emboli, cannula size, and injection methods details was compared for each 3-year period. Both sequential studies provided a comparison of the techniques employed as well as morbidity and mortality outcomes. Results: Sixty-four ABCS surgeons who reported performing BBLs responded to the survey in 2019 and reported performing a total of 22 800 (BBLs) gluteal fat grafting cases in a previous 3-year window from 2016 to 2018. More surgeons used a closed system peristaltic pump in the second part of the study as compared to the first (51% vs 22%) ( P &lt; .01). Two cases required in-hospital treatment of infection in the first survey while zero cases were reported for the second survey period ( P = .07). Twenty-five of 64 (39%) reported injecting fat at least into superficial gluteal muscle during this earlier time frame. In this earliest study, there were 3 total cases of PFE reported (2 fatal PFEs and 1 nonfatal PFEs). In 2022, 85 ABCS surgeons who reported performing BBLs responded to the survey. Around 12 172 gluteal fat grafting cases were reported in the second 3-year study from 2019 to 2021 compared to 22 800 in the first study ( P &lt; .01). There was a total of 34 972 BBLs during the entire 6-year study. Most surgeons (82 of the 85) in the second-phase 3-year study reported injecting fat “exclusively” above the muscle ( P &lt; .01). There were no fatal and non-fatal PFEs reported in the follow-up 3-year study in 2022 of ABCS member data from 2019 to 2021 ( P = .03). Conclusions: The mortality report associated with gluteal fat grafting from this survey among surgical members of the ABCS suggests using the current safety recommendations proposed, including injection of fat in the subcutaneous layer only, have led to a decreased risk of PFEs associated with gluteal fat grafting. The mortality rate was zero (0 out of 12 800) when 96% were injecting above muscle only compared to a mortality rate of 1:11 400 (2 of 22 800 cases) when 39% of 22 800 BBLs performed had fat injected into muscle. While there were more BBLs performed during the earlier 3-year study ( P = .07). The mortality rate significantly decreased in the years when only a small minority of cases had fat injected into the muscle. This study adds to other existing literature from professional organizations’ reports on the safety of gluteal fat grafting using the proper safety measure and recommendations.

Optimized protocol for quantification of extracellular nicotinamide adenine dinucleotide: evaluating clinical parameters and pre-analytical factors for translational research.

Nicotinamide adenine dinucleotide (NAD+), a coenzyme for more than 500 enzymes, plays a central role in energy production, metabolism, cellular signaling, and DNA repair. Until recently, NAD+ was primarily considered to be an intracellular molecule (iNAD+), however, its extracellular species (eNAD+) has recently been discovered and has since been associated with a multitude of pathological conditions. Therefore, accurate quantification of eNAD+ in bodily fluids such as plasma is paramount to answer important research questions. In order to create a clinically meaningful and reliable quantitation method, we analyzed the relationship of cell lysis, routine clinical laboratory parameters, blood collection techniques, and pre-analytical processing steps with measured plasma eNAD+ concentrations. Initially, NAD+ levels were assessed both intracellularly and extracellularly. Intriguingly, the concentration of eNAD+ in plasma was found to be approximately 500 times lower than iNAD+ in peripheral blood mononuclear cells (0.253 ± 0.02 μM vs. 131.8 ± 27.4 μM, p = 0.007, respectively). This stark contrast suggests that cellular damage or cell lysis could potentially affect the levels of eNAD+ in plasma. However, systemic lactate dehydrogenase in patient plasma, a marker of cell damage, did not significantly correlate with eNAD+ (n = 33; r = -0.397; p = 0.102). Furthermore, eNAD+ was negatively correlated with increasing c-reactive protein (CRP, n = 33; r = -0.451; p = 0.020), while eNAD+ was positively correlated with increasing hemoglobin (n = 33; r = 0.482; p = 0.005). Next, variations in blood drawing, sample handling and pre-analytical processes were examined. Sample storage durations at 4°C (0-120 min), temperature (0° to 25°C), cannula sizes for blood collection and tourniquet times (0 - 120 s) had no statistically significant effect on eNAD+ (p > 0.05). On the other hand, prolonged centrifugation (> 5 min) and a faster braking mode of the centrifuge rotor (< 4 min) resulted in a significant decrease in eNAD+ levels (p < 0.05). Taken together, CRP and hemoglobin appeared to be mildly correlated with eNAD+ levels whereas cell damage was not correlated significantly to eNAD+ levels. The blood drawing trial did not show any influence on eNAD+, in contrast, the preanalytical steps need to be standardized for accurate eNAD+ measurement. This work paves the way towards robust eNAD+ measurements, for use in future clinical and translational research, and provides an optimized hands-on protocol for reliable eNAD+ quantification in plasma.

Factors influencing nasal airway pressure and comfort in high-flow nasal cannula oxygen therapy: a volunteer study

BackgroundHigh-flow nasal cannula (HFNC) oxygen therapy is essentially a constant-flow, noninvasive respiratory support system similar to a noninvasive ventilator operating in constant-flow mode. The clinical outcome of HFNC oxygen therapy is strongly associated with the pressure generated by high-flow gas and the patient’s comfort level. This study was performed to explore the relevant factors affecting pressure and comfort of HFNC oxygen therapy in vivo.MethodsThirty-five healthy volunteers were enrolled in the trial. They underwent placement of nasal cannulas of various inner diameters (3, 4 or 5 mm) and treatment with different HFNC devices [HFT-300 (Weishengkang Medical Technology Co., Ltd., Jiangsu China) or H-80 M (BMC Medical Co., Ltd., Beijing China)],and the nasal airway pressure and comfort were assessed. Multiple linear regression was used to determine predictors of airway pressure.ResultsMultiple linear regression showed that the end-expiratory pressure was associated with the flow rate, sex, height, and cannula size. The end-expiratory pressure increased by 0.6 cmH2O per 1-mm increase in cannula diameter, decreased by 0.3 cmH2O per 10-cm increase in participant height (with a 0.35 cmH2O decrease for men), and increased by 1 cmH2O when the flow rate increased by 10 L/min (R2 = 0.75, P < 0.05 for all variables in model). In addition, the pressure generated by the H-80 M device was higher than that generated by the HFT-300 device (P < 0.05). Discomfort manifested as difficulty in expiration, and its severity increased as the cannula diameter increased; however there was no significant difference in comfort between the two HFNC devices (P > 0.05).ConclusionIn volunteers undergoing HFNC oxygen therapy, the nasal cannula diameter, flow rate, sex, height, and device model can affect the nasal airway pressure, and the nasal catheter diameter and flow rate can affect comfort. These factors should be given close attention in clinical practice.Trial registrationChiCTR2300068313 (date of first registration: 14 February 2023, https://www.chictr.org.cn).

Performance Evaluation of Geometrically Different Pediatric Arterial Cannulae in a Pediatric Cardiopulmonary Bypass Model.

To define a reference chart comparing pressure drop vs. flow generated by a set of arterial cannulae currently utilized in cardiopulmonary bypass conditions in pediatric surgery. Cannulae from two manufacturers were selected considering their design and outer and inner diameters. Cannula performance was evaluated in terms of pressure drop vs. flow during simulated cardiopulmonary bypass conditions. The experimental circuits consisted of a Jostra HL-20 roller pump, a Quadrox-i pediatric oxygenator (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set. The circuit was primed with lactated Ringer's solution only (first condition) and with human packed red blood cells added (second condition) to achieve a hematocrit of 30%. Cannula sizes 8 to 16 Fr were inserted into the cardiopulmonary bypass circuit with a "Y" connector. The flow was adjusted in 100 ml/min increments within typical flow ranges for each cannula. Pre-cannula and post-cannula pressures were measured to calculate the pressure drop. Utilizing a pressure drop limit of 100 mmHg, our results suggest a recommended flow limit of 500, 900, 1400, 2600, and 3100 mL/min for Braile arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, respectively. For Medtronic DLP arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, the recommended flow limit is 600, 1100, 1700, 2700, and 3300 mL/min, respectively. This study reinforces discrepancies in pressure drop between cannulae of the same diameter supplied by different manufacturers and the importance of independent translational research to evaluate components' performance.

Veno-arterial extracorporeal membrane oxygenation for cardiogenic shock: one-year outcomes from a cardiac intensive care unit led shock team program

Abstract Background Mechanical circulatory support (MCS) with peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used for severe cardiogenic shock (CS). Purpose To describe the initial experience with peripheral VA-ECMO within a cardiac intensivist team led program. Methods Retrospective analysis of a short-term MCS prospective registry, from 1 September 2021 to 1 December 2022. Clinical and device related variables were reviewed and reported. We assessed both patient outcomes as well as ECMO-related complications. Results A total of 21 patients were included in this analysis (50 ± 13 years-old, 80% male), ranging from SCAI-C (n = 8) to E (n = 5) and with a median predicted mortality by SAVE score of -4 points [IQ -6 - 0] (corresponding to 30% in-hospital survival). All cannulations were done percutaneously, mostly by trained cardiac intensivists and while at the CICU (n = 12). A femoro-femoral configuration was used for all patients. One patient was cannulated at the referring hospital and retrieved to our unit for further care. Three patients were cannulated during intra-hospital cardiac arrest and one patient was cannulated while breathing spontaneously (awake-ECMO). Mean venous and arterial cannula sizes were 22 ± 1.9 Fr and 17 ± 1.6 Fr, respectively. A 7 French (Fr) arterial limb reperfusion cannula was used in 85% of cases. The most frequent etiology was acute decompensation of chronic heart failure (n = 7), followed by acute myocardial infarction related CS (n = 5), fulminant myocarditis (n = 2) and massive pulmonary thromboembolism (n = 2). A left ventricle venting device was used in 70% of patients [intra-aortic balloon pump (n = 10); percutaneous microaxial pump ( n = 2)] and upgrade to a veno-arterio-venous configuration was necessary in one patient due to differential hypoxemia. Mean ECMO-run duration was 8.4 ± 4.8 days while mean CICU length of stay was 22 ± 17.9 In-hospital mortality was 40%. In survivors, decannulation was surgical in all but one patient. The most frequent strategy was bridge to recovery (n = 14). One patient was bridged directly to heart transplant, one to a temporary centrifugal left ventricular assist device (LVAD) and one to a durable magnetically levitated LVAD. Complications were common and included bleeding from cannula insertion sites (n = 19), renal replacement therapy requirement (n= 10), Harlequin syndrome (n = 2), cardiac tamponade (n = 2), intestinal ischemia (n = 3) and limb ischemia (n = 2). Conclusion VA-ECMO performed by cardiac intensivists is a feasible MCS strategy for severe cardiogenic shock patients in whom mortality, while high, was similar to large international published series. Further experience will allow for improvement in patient selection and minimization of device related complications.ECMO VA 1 year single-center experience

Abstract 17212: Arterial Cannula Size and 30-Day Mortality in Adults With Cardiogenic Shock Supported With Venoarterial Extracorporeal Membrane Oxygenation and Concomitant Left Ventricular Mechanical Unloading: An ELSO Registry Analysis

Introduction: VA-ECMO with left ventricular mechanical unloading (LVMU), including intra-aortic balloon pump (IABP) or percutaneous left ventricular assist device (pVAD), is commonly used to support patients with cardiogenic shock (CS). The impact of arterial return cannula size on short-term mortality in the presence of LVMU is unknown. Hypothesis: The 30-day inpatient survival in patients with VA-ECMO and LVMU will be the same with a small vs large arterial cannula. Methods: We queried the ELSO Registry from 2017-2022 for adults with CS receiving VA-ECMO and concomitant LVMU, with either IABP or pVAD placed within -24h to +2h of ECMO initiation. We restricted to patients with body surface area (BSA) 1.8-2.2 m2 and excluded those with central cannulation, multiple ECMO runs, and ECPR. The primary outcome of 30-day inpatient mortality was compared using time-to-event analysis. Secondary outcomes included 24h lactate clearance and rates of acute renal and hepatic injury. Results: Among 2055 patients supported with VA-ECMO and LVMU (54.3% IABP; 45.7% pVAD), 292 (14.2%) patients received a small cannula and 1763 (86.8%) patients a large arterial cannula. Patients with a small cannula were less likely to be male, had smaller BSA, less often had a distal perfusion cannula, and had a lower incidence of pre-ECMO concomitant organ failures (Figure, A). There was no difference in 30-day inpatient mortality between the cannula size groups (Figure, B), which persisted in multivariable modeling with adjusted hazard ratio 0.94 (95% CI: 0.72-1.23), p=0.65. Patients with a small arterial cannula had no significant difference in 24h lactate clearance (Figure, C) or in the rates of acute renal injury (37.3% vs 39.8%, p = 0.42) or hyperbilirubinemia (5.5% vs 6.5%, p=0.52). Conclusions: In adults with CS receiving VA-ECMO with LVMU, the use of a smaller arterial return cannula was associated with no difference in 30-day inpatient mortality or metrics of end-organ perfusion.

Abstract 17180: Association of Arterial Return Cannula Size With Survival in Adults Undergoing Venoarterial Extracorporeal Membrane Oxygenation: An ELSO Registry Analysis

Introduction: Peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used to support critically ill adults with cardiogenic shock (CS), but the impact of arterial cannula size on survival remains poorly understood. Hypothesis: A smaller arterial return cannula will be associated with similar survival. Methods: We queried the ELSO registry for adults undergoing VA-ECMO from 2017-2022 and stratified them into small (&lt;16 Fr) versus large (≥16Fr) arterial cannula size. We restricted the cohort to patients with body surface area (BSA) 1.8-2.2 m 2 and excluded patients with a concomitant left ventricular venting device, central cannulation, and multiple ECMO runs. The primary outcome was 30-day in-hospital mortality and secondary outcomes included 24-hour lactate clearance and rates of on-support acute renal and liver injury. Results: Among 2963 adults receiving peripheral VA-ECMO without a concomitant left ventricular venting device, 491 (16.6%) patients had a small arterial cannula and 2,472 (83.4%) had a larger cannula. Patients with a larger cannula were more often male, had marginally higher BSA, a higher incidence of pre-ECMO organ failures, and more often had a distal perfusion cannula (Figure, panel A). There was no difference in 30-day mortality between patients with small (40.3%) versus large (42.9%) arterial cannula, p= 0.295 (Figure, panel B), which persisted after multivariable modeling: adjusted hazard ratio 0.97 (95% CI: 0.79-1.19, p= 0.78). Lactate clearance at 24 hours of ECMO support (Figure, panel C) and the rates of acute renal injury (37% vs 41%, p = 0.024) and hyperbilirubinemia (4.3% vs 4.3%, p = 0.96) were similar between the two arterial cannula size cohorts. Conclusion: For adult patients undergoing peripheral VA-ECMO support, the use of a smaller (&lt;16F) versus larger (≥16F) arterial return cannula was associated with similar rates of in-hospital mortality and metrics of end-organ perfusion.