Role of next generation sequencing in diagnosis and management of critically ill children with suspected monogenic disorder

Next generation sequencing based diagnosis has emerged as a promising tool for evaluating critically ill neonates and children. However, there is limited data on its utility in developing countries. We assessed its diagnostic rate and clinical impact on management of pediatric patients with a suspected genetic disorder requiring critical care. The study was conducted at a single tertiary hospital in Northern India. We analyzed 70 children with an illness requiring intensive care and obtained a precise molecular diagnosis in 32 of 70 probands (45.3%) using diverse sequencing techniques such as clinical exome, whole exome, and whole genome. A significant change in clinical outcome was observed in 13 of 32 (40.6%) diagnosed probands with a change in medication in 11 subjects and redirection to palliative care in two subjects. Additional benefits included specific dietary management (three cases), avoidance of a major procedure (one case) and better reproductive counseling. Dramatic therapeutic responses were observed in three cases with SCN1A, SCN2A and KCNQ2-related epileptic encephalopathy. A delayed turn-around for sequencing results was perceived as a major limiting factor in the study, as rapid and ultra-rapid sequencing was not available. Achieving a precise molecular diagnosis has great utility in managing critically ill patients with suspected genetic disorders in developing countries.

Indigenous Bubble Continuous Positive Airway Pressure for Children

How to cite this article: Gupta D, Simalti AK. Indigenous Bubble Continuous Positive Airway Pressure for Children. Indian J Crit Care Med 2023;27(11):788-789.

Flexible Fiberoptic Bronchoscopy in Non-ventilated Children in Pediatric Intensive Care Unit: Utility, Interventions and Safety

Objective

To study the utility of flexible fiberoptic bronchoscopy (FFB), and its effects on oxygenation and hemodynamics in children while on respiratory assist devices.

Materials and methods

The data of non-ventilated patients who underwent FFB during their stay in the PICU from January 2012 to December 2019 was retrieved from medical, nurses, and bronchoscopy records. The study parameters, demography, diagnosis, indication, and findings of FFB and interventions done after FFB, were noted, and also the oxygenation and hemodynamic parameters before, during and 3 hours after FFB.

Results

Data from the first FFB of 155 patients were analyzed retrospectively. About 54/155 (34.8%) children underwent FFB while on HFNC. About 75 (48.4%) patients were on conventional oxygen therapy (COT) before FFB. There were 51 (33%) patients who had received mechanical ventilation and were extubated successfully. The 98 (63.2%) children had primary respiratory diseases. Stridor and lung atelectasis were indications for FFB in 75 (48.4%) cases and the commonest bronchoscopic finding was retained secretions in the airways. Based on the FFB findings, 50 medical and 22 surgical interventions were done. The commonest medical and surgical interventions were changes in antibiotics (25/50) and tracheostomy (16/22) respectively. There was a significant fall in SpO₂ and a rise in hemodynamic parameters during FFB. All these changes were reversed after the procedure with no consequences.

Conclusion

Flexible fiberoptic bronchoscopy is a useful tool to diagnose and guide interventions in non-ventilated pediatric intensive care unit (PICU). There were significant but transient changes in oxygenation and hemodynamics with no serious consequences.

How to cite this article

Sachdev A, Gupta N, Khatri A, Jha G, Gupta D, Gupta S, et al. Flexible Fiberoptic Bronchoscopy in Non-ventilated Children in Pediatric Intensive Care Unit: Utility, Interventions and Safety. Indian J Crit Care Med 2023;27(5):358-365.

Helium line ratio imaging in the C-2W divertor

A 2D imaging instrument has been designed and deployed on C-2W ("Norman") [H. Gota et al., Nucl. Fusion 61, 106039 (2021)] to study the plasma in the expander divertor by simultaneously measuring three neutral helium spectral lines. Ratios of these images, in conjunction with a collisional-radiative model, yield 2D maps of electron temperature and density. Almost the entire radial plasma cross-section (∼60 cm) can be mapped with a spatial resolution ≲1 cm. These data can, in principle, be acquired at 3 kHz. The neutral helium target is provided by a custom-built supersonic gas injector located inside the divertor vessel, which injects helium toward the magnetic axis and perpendicular to the camera sight-cone. Images of helium emission and reconstructed electron density and temperature profiles of the plasma produced from an end gun are presented. Voltages applied to concentric annular electrodes located in the divertors are used to stabilize beam-driven field reversed configuration plasmas. Magnetic field expansion is also employed to thermally isolate electrons from the end electrodes. Measurements of electron temperature and density in the divertor are important in order to study the effects of both the electrostatic biasing and the divertor magnetic field on electron confinement, neutral gas transport, and the overall machine performance.

OC-003 PORT POSITIONS IN TEP FOR SHORT PATIENTS: OUR EXPERIENCE

Introduction

Totally extraperitoneal repair (TEP) is a popular technique for repair of inguinal hernia. One common technique of TEP involves placement of one 10 mm port 1–2 cm below the umbilicus just off the midline, one 5 mm port 2–3 cm above the pubic symphysis, and a third 5 mm port between these 2 ports in the midline (Figure 1a). In case the distance from the superior border of the symphysis pubis to the inferior edge of the umbilicus is less than 15 cm, this leads to crowding of instruments and results in ergonomic problems during the operation. Daes has popularized eTEP for this indication. The aim is to shift the first 10 mm port to a position 5 cm superior and 4 cm lateral to the umbilicus (Figure 1b). eTEP has also found application in the repair of ventral hernias. However, for most inguinal hernias, we feel that eTEP is an overkill.

Methods

We place the first 10 mm port at the level of the superior border of the umbilicus and just lateral to it (Figure 1c). The two 5 mm ports are placed in the midline. Initial dissection is performed telescopically.

Results

This technique provides 2–3 cm of extra working space, which improves ergonomics while operating on patients with a short pubo-umbilical distance. Other parameters like operating time, postoperative pain and other complications remain the same.

Conclusion

We recommend placement of the 10 mm port at the superior border of the umbilicus, particularly in short patients.

P-011 FEASIBILITY OF VENTRAL-TAPP FOR VENTRAL HERNIA REPAIR IN A LOW INCOME COUNTRY LIKE INDIA

Aim

Minimal invasive repair is now the established procedure for ventral hernia. Surgeons are now validating newer techniques each year to deal with the ventral hernia. It becomes difficult to choose, best fit technique from this large armamentarium. For a low income country like India, ventral- trans abdominal preperitoneal (TAPP) technique is cost effective and uses simple polyester or polypropylene mesh.

Methods

For this article we used our experience with ventral-TAPP performed from July 1, 2021 to May 31, 2022. Patients were followed up for 6 months.

Results

In the above time period, we had performed 10 ventral-TAPP. Out of these, 3 had completed the follow up. Median age was 45.0 years, BMI was 26.56 kg/m2. One patient was male (33.33%). All patients were presented to surgery due to bulge or pain in the anterior abdominal wall.

The median hernia defect measured 80 mm, median mesh diameter was 15 cm and median operative time was 125 min. No intraoperative complications occurred.

Postoperatively, none of the patients developed complications. Length of hospital stay was 3.0 days. Six months after surgery, neither recurrence nor chronic pain were recorded.

Conclusion

We have concluded that mesh used in repair with ventral-TAPP costs one fourth to one-fifth to that of composite mesh used in intraperitoneal onlay mesh (IPOM) repair with the comparable results. So in a low income country like India, ventral TAPP should be a preferred approach.

Indication-based timing of tracheostomy and its effects on outcome in the pediatric intensive care unit

OBJECTIVES

The objective of study was to find an association between the timing of tracheostomy with duration of mechanical ventilation (MV) and length of stay (LOS) in pediatric intensive care unit (PICU) and hospital.

METHODS

The data were collected prospectively from 2000 to 2018 and were analyzed retrospectively. Data included clinical diagnosis, indication, and duration (days) of MV, LOS in PICU and hospital before and after tracheostomy. Patients who did not receive MV or underwent MV for <24 h were excluded. According to the indication of tracheostomy enrolled patients were divided into four groups-airways anomalies (AA), central neurological impairment (CNI), cardiopulmonary insufficiency (CPI), and neuromuscular disorders (NMD). Patients in each group were divided into early (ET) and late tracheostomy (LT) category based on the median (interquartile range interquartile range [IQR]) days of pretracheostomy MV.

RESULTS

Two hundred and fifty six patients were analyzed. The frequency and median [IQR] days of pretracheostomy MV were -AA 54 [7(3,16)], CNI 120 [12(9,16)], CPI 51 [25(16.5,30.5)], and NMD 31[12(8,16.5)]. In AA patients, median (IQR) durations of posttracheostomy MV [2(1,5.2) versus 3.5(2,12); p = 0.032], PICU [7(5,8.2) versus11(7,18); p = 0.004] and hospital [12(9.7,21) versus 21.5(12,28); p = 0.027] stays were lower in ET as compared with LT group. Posttracheostomy MV duration was significantly short in ET patients with CNI and NMD (p < 0.005). The total days of MV, PICU and hospital stay were significantly lower in ET as compared with LT patients in all four groups (p < 0.01).

CONCLUSION

As compared with LT, ET patient had shorter durations of total MV and PICU and hospital stay.

Resonance Excitations in ^{7}Be(d,p)^{8}Be^{*} to Address the Cosmological Lithium Problem

The anomaly in lithium abundance is a well-known unresolved problem in nuclear astrophysics. A recent revisit to the problem tried the avenue of resonance enhancement to account for the primordial ^{7}Li abundance in standard big-bang nucleosynthesis. Prior measurements of the ^{7}Be(d,p)^{8}Be^{*} reaction could not account for the individual contributions of the different excited states involved, particularly at higher energies close to the Q value of the reaction. We carried out an experiment at HIE-ISOLDE, CERN to study this reaction at E_{c.m.}=7.8  MeV, populating excitations up to 22 MeV in ^{8}Be for the first time. The angular distributions of the several excited states have been measured and the contributions of the higher excited states in the total cross section at the relevant big-bang energies were obtained by extrapolation to the Gamow window using the talys code. The results show that by including the contribution of the 16.63 MeV state, the maximum value of the total S factor inside the Gamow window comes out to be 167 MeV b as compared to earlier estimate of 100 MeV b. However, this still does not account for the lithium discrepancy.

Differentiating border-zone tissue from post-infarct scar using ripple mapping during VT ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Areas of post-infarct ventricular scar and border-zone slow conduction are often highlighted on a bipolar voltage map with generalized values 0.5mV–1.5mV. The true voltage that differentiates regions of conducting from non-conducting tissue is unknown. Ripple Mapping (RM)displays allows conducting tissue to be seen as areas supporting Ripple activation, and non-conducting tissue as areas devoid of Ripple activation.

Purpose

We describe application of Ripple Maps to differentiate areas of scar from conducting tissue during ischemic VT ablation.

Methods

Dense bipolar voltage maps were created (Pentaray catheter, pacing 80-100bpm) and presented as a single value (e.g. 0.5mV-0.5mV) to binarize the color display (red and purple). RMs were superimposed on the voltage map and played above a pre-set noise threshold (&gt;0.05mV). The voltage map mV limit was sequentially reduced ("border-zone threshold") until only those areas devoid of Ripple bars appeared red. The surrounding border-zone supporting ripple activation thus appeared purple. We performed off-line analysis of border-zone voltage thresholds from a series of RM guided VT ablations.

Results

10 consecutive patients (LVEF 32.3±7.5%) with remote myocardial infarction underwent VT ablation (median 19days (IQR 8-33) since last VT). Bipolar voltage mapping (5873±2841 points, median shell area 224cm2), revealed voltages&lt;0.5mV covered a median 11% (IQR 7-17%) of the shell. The border-zone voltage threshold was median 0.2mV (range 0.12mV - 0.3mV). Non-conducting tissue below this value covered only median 5% (IQR 3-7%) of the entire shell. VT was mappable in 4 patients, and the isthmus was bordered by tissue below the same border-zone threshold as found in normal rhythm. The border-zone was homogenized with ablation(40-50W, median 29 mins (IQR 22-33), and clinical VT was non-inducible in all, and 9 pts (91%) remain sustained VT-free at median 90-day follow-up (IQR 23-139), 2-weeks blanking period).

Picture 1 presents an infero-lateral LV infarct collected in an RV paced rhythm (7340points) and displayed at conventional bipolar voltage settings 0.5-1.5mV. Tissue with voltages&lt;0.5mV appear red and cover 30% of the total area. In this case, this border-zone voltage threshold was defined as 0.25mV. Non-conducting tissue, seen as areas devoid of ripple bars below this value, now appeared as red, and covered only 11% of the total area. Picture 2 demonstrates the morphologies of 4 poorly tolerated induced VTs during this case. Each had near perfect pacemaps to the exit sites of border-zone tissue defined using this approach, and were targets for ablation resulting in complete non-inducibility and no VT recurrence in early follow-up.

Conclusion

The bipolar voltage that differentiates putative scar from bordering conducting tissue is unique to each patient, and far lower than 0.5mV-1.5mV. RM presents a practical approach to visualize the border-zone activation to guide ablation.

Hematopoietic stem cell transplantation for hemoglobinopathies: Progress and prospects

Allogeneic bone marrow transplantation from an HLA-identical donor is currently the only means of curing thalassemia . Transplant outcome depends upon the presence of risk factors (hepatomegaly, portal fibrosis and poor quality of chelation). patients are defined to have class I - if no risk factor, class II with one or two and class III - if all three risk factors are present. For patients under 16 years of age, for class I, class II and III the probabilities of survival are approximately 95%, >80% and 60-70%, respectively. The risk of transplant related morbidity& mortality is low when transplant is done at an early age. Currently, busulfan, cyclophospahmide and antithymocyte globulin based combination is used for conditioning. More than 200 patients with sickle cell disease (SCD) have undergone allogeneic SCT with long term survival in >80% of patients. Results are better if donor is an HLA-identical sibling and if transplant is done early in the course of disease. Presently, experience with reduced intensity SCT and matched unrelated donor transplant is limited to recommend their routine use.

COVID-19-associated Multisystem Inflammatory Syndrome in Children: A Multicentric Retrospective Cohort Study

Background

Multisystem inflammatory syndrome in children (MIS-C) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new entity affecting a small percentage of children during the COVID-19 pandemic.

Materials and methods

Demography, clinical, and laboratory variables of children admitted from April to September 2020 with MIS-C were studied retrospectively at eight hospitals in Delhi, India.

Results

We identified 120 patients [median age: 7 years (interquartile range (IQR): 4–10)] with male-to-female ratio of 2.3:1. Overall, 73 out of 120 children (60.8%) presented with shock, 63 (52.5%) required inopressor support, and 51 (43%) required respiratory support. We categorized the cohort into three observed clinical phenotypes: MIS-C with shock (n = 63), MIS-C with Kawasaki disease (KD) (n = 23), and MIS-C without shock and KD (n = 34). Atypical presentations were hypothermia, orchitis, meningoencephalitis, demyelination, polyneuropathy, pancreatitis, and appendicitis. Ninety-four percent had laboratory evidence of SARS-CoV-2 (78.3%, seropositive and 15.8%, RT-PCR positive). The median C-reactive protein (CRP) was 136 mg/L (IQR, 63.5–212.5) and ferritin was 543 ng/mL (IQR, 225–1,127). More than 90% received immunomodulatory therapy (intravenous immunoglobulins and/or steroids) with an excellent outcome (96% survived). CRP and absolute neutrophil count (ANC) were correlated statistically with severity.

Conclusion

MIS-C data from Delhi are presented. Rising CRP and ANC predict the severe MIS-C.

How to cite this article

Mehra B, Pandey M, Gupta D, Oberoi T, Jerath N, Sharma R, et al. COVID-19-associated Multisystem Inflammatory Syndrome in Children: A Multicentric Retrospective Cohort Study. Indian J Crit Care Med 2021;25(10):1176–1182.

Primitive neuroectodermal tumor of the kidney: a rare case

Background

Primitive neuroectodermal tumor commonly occurs in bones and is equivalent to Ewing’s sarcoma. Very few cases have been reported in the literature and they had a very different presentation and very aggressive behavior.

Case presentation

We present a case of a young 23-year-old male who presented with complaints of pain in left lumbar region of abdomen since 8 months and hematuria off and on. CT scan of the abdomen was done which revealed a large heterogeneously enhancing mass lesion in the left lumbar region arising from the superior and mid-pole of left kidney showing multiple non-enhancing necrotic areas. A diagnosis of left renal cell carcinoma was kept. Through the transperitoneal approach, the left kidney was approached and a left radical nephrectomy was done. The histopathology report revealed the tumor cells to be positive for CD99 and focally positive for Vimentin and negative for cytokeratin thereby making a diagnosis of primary neuroectodermal tumor (PNET).

Conclusions

Renal PNET is a rare renal malignancy that should be kept in the differential diagnosis of a renal SOL especially when it is a presenting feature in adolescent and young adult. It has a very aggressive course and multimodal therapy has to be considered in its treatment

COVID-19-associated mucormycosis presenting to the Emergency Department-an observational study of 70 patients

BACKGROUND

Mucormycosis (MM) is a deadly opportunistic fungal infection and a large surge in COVID-19-associated mucormycosis (CAM) is occurring in India.

AIM

Our aim was to delineate the clinico-epidemiological profile and identify risk factors of CAM patients presenting to the Emergency Department (ED).

DESIGN

This was a retrospective, single-centre, observational study.

METHODS

We included patients who presented with clinical features or diagnosed MM and who were previously treated for COVID-19 in last 3 months of presentation (recent COVID-19) or currently being treated for COVID-19 (active COVID-19). Information regarding clinical features of CAM, possible risk factors, examination findings, diagnostic workup including imaging and treatment details were collected.

RESULTS

Seventy CAM patients (median age: 44.5 years, 60% males) with active (75.7%) or recent COVID-19 (24.3%) who presented to the ED in between 6 May 2021 and 1 June 2021, were included. A median duration of 20 days (interquartile range: 13.5-25) was present between the onset of COVID-19 symptoms and the onset of CAM symptoms. Ninety-three percent patients had at least one risk factor. Most common risk factors were diabetes mellitus (70%) and steroid use for COVID-19 disease (70%). After clinical, microbiological and radiological workup, final diagnosis of rhino-orbital CAM was made in most patients (68.6%). Systemic antifungals were started in the ED and urgent surgical debridement was planned.

CONCLUSION

COVID-19 infection along with its medical management have increased patient susceptibility to MM.

MIS-C is a Clinically Different Entity from Acute COVID-19 in Adults

Mehra B, Aggarwal V, Kumar P, Gupta D, Kundal M, Kumar A, et al. MIS-C is a Clinically Different Entity from Acute COVID-19 in Adults. Indian J Crit Care Med 2021;25(8):954–955.

Evaluation of the feasibility and accuracy of remote mobile app-based self-reported atrial fibrillation risk factor assessment in patients with atrial fibrillation: TeleCheck-AF results

Background

Previously, we introduced the TeleCheck-AF approach, which is an on-demand mobile health (mHealth) infrastructure incorporating mobile app-based heart rate and rhythm monitoring as well as mobile app-based self-reported atrial fibrillation (AF) risk factor assessment to allow comprehensive remote AF management through teleconsultation. Herein, we evaluated the feasibility and accuracy of remote mobile app-based self-reported AF risk factor assessment in AF patients.

Methods

In our University Medical Center, 545 patients were managed within the TeleCheck-AF project by an on-demand heart rate and rhythm mHealth infrastructure through teleconsultation. Patients were asked to fill in a short mobile app-based 10-item questionnaire related to AF risk factors. A reminder to complete the questionnaire automatically popped-up after the following four heart rate and rhythm recordings. Furthermore, patient's medical history was retrieved from the electronic health records (EHRs).

Results

Out of 545 patients, 542 (99.4%) patients (217 female, age 67 (59–72) years) completed the mobile app-based 10-item questionnaire and were included in this analysis. The number of patients with diabetes mellitus was similar in the EHRs and mobile app-based questionnaire (both 11.3%, p=1.000). There was no significant difference in the number of patients who had a medical history of transient ischemic attack (TIA)/cerebrovascular accident (CVA) and artery disease (coronary artery disease and peripheral artery disease) in the EHRs and mobile app-based questionnaire (11.4% vs 12.2%, p=0.608 and 14.8% vs 13.3%, p=0.366, respectively). Heart failure was more frequently reported in the mobile app-based questionnaire compared to the EHRs (33.4% vs 14.0%, p&lt;0.001). A total of 260 (48.0%) patients had a diagnosis of hypertension verified in EHRs and only 239 (44.1%) patients reported hypertension in the mobile app-based questionnaire (p=0.044). There was no significant difference in number of patients with CHA2DS2-VASc-score ≥2 between the EHRs and mobile app-based questionnaire (64.2% vs 66.1%, p=0.275). The accuracy of mobile app-based assessment of diabetes mellitus was 85.4%, of TIA/CVA 78.9%, of artery disease 60.9%, of heart failure 78.8%, and of hypertension 89.3%.

Conclusion

Patient self-reported AF risk factors by a remote mobile app-based assessment is feasible and may be useful for future digital trials and comprehensive remote AF management through teleconsultation.

Funding Acknowledgement

Type of funding sources: None.

Chest sonography versus chest radiograph in children admitted to paediatric intensive care - A prospective study

There is a paucity of studies on the correlation between chest radiograph and ultrasound (US) in children. Our objective was to study the correlation between bedside chest radiograph and ultrasound findings in 413 children with 1002 episodes of chest radiograph and US enrolled for a prospective, double-blinded observational study in a multidisciplinary paediatric intensive care unit. Weighted κ statistic for agreement was different for right and left lungs and varied from 50% for left pleural effusion to 98% for right pneumothorax. Pulmonary oedema, pneumothorax and pleural effusion were diagnosed by ultrasound alone in a significantly higher number of patients as compared to chest radiograph (P = 0.001). Chest ultrasound is therefore deemed more sensitive than chest radiograph in detection of pleural effusion, pulmonary oedema and pneumothorax.

Safety and acute clinical outcomes of atrial fibrillation catheter ablation in octogenarians: a multicentre evaluation with a matched younger cohort

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Sven Knecht and the International Octogenarian AF ablation group

Background

Octogenarians are a fast-growing demographic with a high burden of atrial fibrillation (AF). There are limited data on procedural safety and acute outcomes of catheter ablation (CA) for AF in this group.

Purpose

Investigation of complications & outcomes in octogenarians undergoing CA for AF.

Methods

Data on all octogenarian patients who underwent AF ablation at nine European cardiology centres between 2013 and 2019 were retrospectively analysed and matched with control patients aged &lt;80 years.  The characteristics used for matching were type of AF, type of procedure (de novo or redo), & the year of procedure.

Results

216 octogenarians (81.9 ± 1.9 years; 52.8% females) underwent an AF ablation procedure, and were matched with 216 patients aged &lt;80 years (62.4 ± 9.5 years, 34.7% females), p &lt;0.001 for both. The proportion of paroxysmal and persistent AF was 43.5% & 56.5% respectively in both groups, and 79.3% of the procedures were de novo. RF ablation made up 75.4% & 75.9% (p = 0.90) procedures in octogenarians and controls respectively.  17 complications occurred in 14 (7.9%) octogenarian patients and 11 in 11 (5.1%) patients in the younger matched cohort (p = 0.07). There were 4.2% & 1.9% major complications (p= 0.17) and 3.7% & 3.2% minor complications (p= 0.77) in the octogenarian & younger cohorts respectively. Complications in octogenarians consisted of groin complications (n = 6), pneumonia (n = 3), pericardial effusion (n = 2), phrenic nerve injury (n = 2), pulmonary oedema (n = 1), gastroparesis (n = 1), stroke (n = 1). Acute procedural success rates were 99.1% & 99.5% (p = 0.62) The complication rates were similar for RF; 6.0% vs 5.4% (p = 0.79) and Cryoballoon; 14.0% vs 4.1% (p = 0.09) in both octogenarians and younger cohort respectively.

Conclusion

In spite of significantly higher overall risk profile of octogenarians undergoing AF ablation, there is no difference in acute procedural success and complication rates as compared to younger patients Catheter ablation of AF in octogenerians Octogenarians n = 216 Matched Controls (aged &lt; 80yrs) n = 216 P value Age (yrs), mean (SD)s 81.9 (1.9) 62.4(9.5) &lt; 0.0001 Females, (%) 52.8 34.7 0.0002 CHA2DS2-VASc, mean (SD) 3.6 (1.2) 1.4 (1.3) &lt; 0.0001 Mean LA size, mm 42.8 ± 8.3mm 45.8 ± 16.2 0.062 Impaired LV function, (%) 23.7 17.9 0.206 IHD, (%) 20.7 5.9 &lt; 0.0001 Procedural time (mins), mean (sd) 150.6 (69.7) 148.9 (64.4) 0.914 All complications, n (%) 17 (7.9) 11 (5.1) 0.073

The TeleCheck-AF project on remote app-based management of atrial fibrillation during the COVID-19 pandemic: Patient experiences

Funding Acknowledgements

OnBehalf

Aims

Methods

Results

Conclusions

Ablation Index-guided 50W ablation for left atrial posterior wall isolation compared with lower powers: feasibility and lesion level analysis

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Groupe de Rythmologie de la Société Française de Rythmologie

Background 

Posterior Wall Isolation (PWI) is increasingly performed for Atrial Fibrillation (AF). The use of Ablation Index (AI)-guided 50W ablation for PWI has not been described, nor the interplay between ablation parameters at this power when compared to lower powers. 

Methods 

40 consecutive AF patients (26 males, 65.5 ± 10.0 years. 95% non-paroxysmal AF) underwent PWI following pulmonary vein isolation. A roof line and floor line were created with point-by-point ablation, targeting a contact force (CF) of 10-30g, AI 550-600 on the roof and 400-450 on the floor, and inter-tag distance of &lt;6mm. 35-40W powers were used for the first 20 patients, and 50W used for the next 20. Generator impedance was monitored in real time for each lesion. Ablation inside the box was delivered in case of failure of first pass isolation (FPI). All VisiTags (n = 959) were analyzed retrospectively. 

Results 

PWI was successful in 19(95%) of the 35-40W group and in all 20 patients in the 50W group, with FPI seen in 8(40%) and 10(50%) respectively, p = 0.53. The mean CF and number of RF applications on the roof. floor and inside the box were similar between the two groups. Ablation time per lesion (10.4 [8.8-12.5]sec) and total ablation time per patient (3.84[3.34-4.66] min) were shorter in the 50W group as compared to 35-40W (13.0 [11.6-16.2] sec and 5.86 [4.23-7.73] min respectively), p &lt; 0.005. The mean AI and Impedance Drop were larger in the 50W group (Table). There was no steam pop observed in any of the 959 radiofrequency applications. 

Conclusion 

Ablation Index guided 50W ablation has a very high success rate for posterior wall isolation with shorter ablation times and higher impedance drop compared to conventional powers. Steam pops may be avoidable by targeting CF &lt; 30g, and by monitoring impedance in real-time. 50W Group(N = 458) 35-40W Group(N = 501) p-value Number of lesions (s, IQR)Roof lineFloor lineAdditional ablation inside box 21.5 [19.5-26.3]7.0 [5.8-9.0]13.0 [10.8-14.3]6.0 [6.0-6.8] 24.0 [20.8-29.5]8.0 [6.0-10.0]12.5 [10.8-14.0]5.5 [2.8-9.0] 0.330.180.850.59 Ablation Time per lesion (s, IQR)Roof lineFloor lineAdditional ablation inside box 10.4 [8.8-12.5]13.0 [10.9-16.0]9.9 [8.7-11.4]8.1 [6.9-9.0] 13.0 [11.6-16.2]14.5 [12.4-19.0]12.7 [11.4-15.9]11.8 [10.6-14.0] &lt;0.005&lt;0.005&lt;0.005&lt;0.005 Total RF Time (min, IQR)Roof lineFloor lineAdditional ablation inside box 3.84 [3.34-4.66]1.54 [1.15-1.90]2.06 [1.68-2.54]0.79 [0.65-1.07] 5.86 [4.23-7.73]1.98 [1.62-2.59]2.78 [2.28-3.25]1.07 [0.59-1.42] &lt; 0.0050.0190.0090.50 Impedance Drop (ohms, IQR)Roof lineFloor lineAdditional ablation inside box 7.4 [5.2-10.3]8.7 [6.1-11.3]6.9 [5.0-10.1]7.1 [5.4-9.8] 6.9 [4.8-9.7]7.5 [5.1-10.0]6.0 [4.2-8.3]8.3 [5.8-10.9] 0.0070.04&lt; 0.0050.17 Contact Force (g, IQR)Roof lineFloor lineAdditional ablation inside box 21.1 [14.5-30.3]23.9 [17.8-32.7]19.2 [13.2-25.3]25.5 [18.5-36.9] 21.2 [14.9-28.1]24.3 [17.2-30.3]19.0 [14.1-25.0]23.1 [16.9-31.7] 0.560.450.870.21 Ablation Index (IQR)Roof lineFloor lineAdditional ablation inside box 471 [441-519]560 [509-571]453 [436-475]461 [430-488] 461 [434-493]502 [466-541]446 [426-464]455 [434-478] &lt; 0.005&lt; 0.005&lt; 0.0050.59 Lesion level analysis for Posterior Wall Isolation

Remote app-based management of atrial fibrillation during the COVID-19: The centre characteristics and experiences of the European TeleCheck-AF project

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

TeleCheck-AF Investigators

Aims

Herein we describe the characteristics, inclusion rates and experiences from participating centres in the European TeleCheck-AF project. TeleCheck-AF is a multicentre international project initiated to maintain care delivery for patients with atrial fibrillation (AF) during COVID-19 through teleconsultations supported by an on-demand photoplethysmography-based heart rate and rhythm monitoring app (FibriCheck®). 

Methods

Two surveys exploring centre characteristics (n = 25) and centre experiences (n = 23) were completed.

Results

Most centres were academic (64%) and specialized public cardiology/district hospitals (36%). Majority of centres had AF outpatient clinics (64%) and only 36% had AF ablation clinics. The time required to start patient inclusion and total number of included patients in the project was comparable for centres experienced (56%) or inexperienced in mHealth use. Within 28 weeks, 1930 AF patients were recruited, mainly for remote AF control (31% of patients) and AF ablation follow-up (42%). Average inclusion rate was highest during the lockdown restrictions and reached a steady state at a lower level after easing the restrictions (188 vs 52 weekly recruited patients). Majority (>80%) of the centres reported no problems during the implementation of the TeleCheck-AF approach. Centres agreed that the on-boarding process of their center in the TeleCheck-AF project was simple and access to the patients measurements via stand-alone cloud infrastructure was trouble-free and possible from the first day on. They also agreed that remote heart rate and rhythm assessment by the FibriCheck® app around teleconsulatation supported their medical decision making; that their patients responded positively to use FibriCheck® for seven days; and that they felt comfortable to interpret PPG recordings. 

Conclusions

Despite different health care settings and mHealth experiences, the TeleCheck-AF approach could be set up within an extremely short time and easily used in different European centres during COVID-19.

Assessing atrial fibrillation ablation priority during COVID-19 -does use of patient questionnaires help in stratification above physician assessment?

Funding Acknowledgements

Type of funding sources: None.

Introduction

Catheter ablation for atrial fibrillation (AF) is largely offered for symptomatic relief. The ORBIT registry has shown that patients with a higher EHRA class and lower quality of life (QoL) scores (AFEQT score <65.7) are more likely to suffer emergency hospital admissions. To help prevent unplanned AF admissions and to best utilise the reduced capacity for elective work during the COVID-19 pandemic, it has become even more important to prioritise the most symptomatic AF patients for ablation. Purpose: To evaluate the accuracy of a subjective symptom-based clinician prioritisation schema compared to objective patient-completed quality of life (QoL) scores. Methods: In July 2020, all elective cases awaiting AF ablation at our institution were categorised by their cardiologist as either category 1 (C1-urgent), category 2 (C2–priority, procedure to be done during the ongoing COVID-19 pandemic) or category 3 (C3–routine, procedure may be delayed until post pandemic). This categorisation was based on review of clinic letters where EHRA AF symptom class or PROMS are not routinely recorded.  All patients in C2 and C3 were then posted an AF specific (AFEQT) and a generic (EQ5D) QoL questionnaire to complete. Physicians were blinded to patient responses on the QoL questionnaires. Results: Details of physician prioritisation and completed questionnaires were available for 85 patients (62 ± 10 years, PAF in 61%, males 66%). The 18 patients that had been categorised in C2 (priority) group were found to have a significantly lower AFEQT score (30.4, IQR 17.2-51.9) compared to the 67 patients classed in C3 (routine) group (56.5, IQR 32.1-74.1; p < 0.01)(Figure 1a). EQ5D scores also tended to be lower in the C2 patients (0.7, IQR 0.4-0.8) compared to C3 (0.8, IQR 0.6-0.9; p = 0.056) (Figure 1c). 16 (89%) patients in C2 had significant AF-related impact on QoL (as defined as AFEQT score <65.7) compared to 42 (63%) of patients in C3.  However, there was significant overlap between groups (Figure 1b). 4 patients in C3 had unplanned AF related hospital admissions while awaiting ablation, as compared to none in C2. The median AFEQT score of these 4 patients was 23.3, indicating that they were highly symptomatic despite being classified in C3 by their cardiologist. Conclusion : Physician assessments are moderately accurate in prioritising patients awaiting AF ablation. The addition of formal patient-completed QoL assessment such as with AFEQT, helps to identify the most symptomatic patients at risk of emergency hospital admission, and physicians should consider using these as part of routine assessment, especially during the COVID pandemic.

Novel deep transfer learning model for COVID-19 patient detection using X-ray chest images

Around the world, more than 250 countries are affected by the COVID-19 pandemic, which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This outbreak can be controlled only by the diagnosis of the COVID-19 infection in early stages. It is found that the radiographic images are ideal for the fastest diagnosis of COVID-19 infection. This paper proposes an ensemble model which detects the COVID-19 infection in the early stage with the use of chest X-ray images. The transfer learning enables to reuse the pretrained models. The ensemble learning integrates various transfer learning models, i.e., EfficientNet, GoogLeNet, and XceptionNet, to design the proposed model. These models can categorize patients as COVID-19 (+), pneumonia (+), tuberculosis (+), or healthy. The proposed model enhances the classifier's generalization ability for both binary and multiclass COVID-19 datasets. Two popular datasets are used to evaluate the performance of the proposed ensemble model. The comparative analysis validates that the proposed model outperforms the state-of-art models in terms of various performance metrics.

Measurements of impurity ion temperature and velocity distributions via active charge-exchange recombination spectroscopy in C-2W

In TAE Technologies' C-2W experiment, electrode biasing is utilized for boundary control of a field-reversed configuration (FRC) plasma embedded in a magnetic mirror. Understanding the underlying physics associated with FRC rotation, stabilization, and heating is crucial for improving machine performance. Impurity ion rotation and temperature are sensitive to biasing effects, and measurements of these quantities can provide insight into important plasma dynamics and overall effectiveness of the biasing system. To this end, a charge-exchange recombination spectroscopy (ChERS) diagnostic was developed and deployed to measure local impurity ion temperature and velocity in the confinement vessel of C-2W. The system utilizes a new diagnostic neutral beam (40 keV, 8.5 A) and a fiber-coupled spectrometer with an image-intensified high-speed camera to measure beam-induced spectral line emission at multiple lines-of-sight. Design details and the first experimental results obtained with this new diagnostic are presented and discussed.

Measurement of E × B drift of impurities in the C-2W inner divertor using spatial heterodyne spectroscopy

Edge control in the C-2W field-reversed configuration experiment is crucial for the stability and energy confinement of the core plasma. Such edge control is achieved by electrical biasing on the end-on electrode plates. The radial electric field generated by the electrode biasing can be measured by E × B induced drift of impurity ions. Spatial heterodyne spectroscopy (SHS) is a promising method of high light throughput spectroscopy. Doppler shifted spectra of O⁴⁺ ion emission lines have been measured using a novel, in-house built SHS system. The electric field in the jet plasma inside the inner divertor of C-2W was estimated using the temporal profile of the rotational velocity of the oxygen ions. SHS system details, obtained measurements, and the methods of improving the system performance will be discussed.

Comprehensive imaging of C-2W plasmas: Instruments and applications

The C-2W device ("Norman") [Gota et al., Nucl. Fusion 59, 112009 (2019)] has produced and sustained beam-driven field-reversed configuration (FRC) plasmas embedded in a magnetic mirror geometry using neutral beams and end-bias electrodes located in expander divertors. Several discrete vessels comprise this device, and many imaging instruments are required in order to view the plasma throughout. To meet this need, a suite of spatially and radiometrically calibrated, high-speed camera systems have been deployed. Besides global visualization of the plasma evolution and macro-stability, this imaging suite has been used in a variety of applications. One example application is a tomographic reconstruction of passive impurity emission. Calculation of the magnetic field in the equilibrium vessel is complicated by eddy currents in conducting structures and internal currents in the high-β FRC plasma. In addition, thus far non-perturbative measurements of internal field have not been available. The tomographic reconstruction of O⁴⁺ impurity emission enables an independent visualization of the plasma geometry, serving as a check on magnetic modeling and indirect evidence for field reversal within the FRC. A second application uses the cameras to view the Balmer-α emission throughout the plasma in order to estimate the ionization rate in each region. These rates can then be incorporated into particle balance calculations and a circuit model for currents from the end-bias electrodes. Finally, arcing on the electrode surfaces is identified through automated image processing of carefully selected spectral line emission.

Electrocardiometry Fluid Responsiveness in Pediatric Septic Shock

Hemodynamic monitoring and categorization of patients based on fluid responsiveness is the key to decisions prompting the use of fluids and vasoactive agents in septic shock. Distinguishing patients who are going to benefit from fluids from those who will not is of paramount importance as large amounts of fluids used conventionally based on surviving sepsis guidelines may be detrimental. Noninvasive monitoring techniques for the assessment of various cardiovascular parameters are increasingly accepted as the current medical practice. Electrical cardiometry (EC) is one such method for the determination of stroke volume, cardiac output (CO), and other hemodynamic parameters and is based on changes in electrical conductivity within the thorax. It has been validated against gold standard methods such as thermodilution [Malik V, Subramanian A, Chauhan S, et al. World J 2014;4(7):101-108] and is being used more often as a point-of-care noninvasive technique for hemodynamic monitoring. EC is Food and Drug Administration approved and validated for use in neonates, children, and adults. A meta-analysis in 2016, including 20 studies and 624 patients comparing the accuracy of CO measurement by using EC with other noninvasive technologies, demonstrated that EC was the device that offered the most correct measurements. The article in the current issue of IJCCM by Rao et al. (2020) has extended the use of EC to categorize pediatric patients with septic shock into vasodilated and vasoconstricted states based on systemic vascular resistance and correlate the categorization clinically. The authors also studied the changes in hemodynamic parameters after an isotonic fluid bolus of 20 mL/kg was administered. This is a pilot prospective observational study of 30 patients, which has given an insight into physiological rearrangements following fluid administration in patients with septic shock. How to cite this article: Gupta D, Dhingra. Electrocardiometry Fluid Responsiveness in Pediatric Septic Shock. Indian J Crit Care Med 2021;25(2):123-125.