Thicker Posterior Subcutaneous Adipose Tissue (SAT) During Peri-arrest Period is Associated Favorable Neurological Outcome at Hospital Discharge in Patients Achieving Return of Spontaneous Circulation (ROSC) After IHCA: an Observational Study

doi:10.21203/rs.3.rs-5329237/v1

Download PDF

Research Article

Thicker Posterior Subcutaneous Adipose Tissue (SAT) During Peri-arrest Period is Associated Favorable Neurological Outcome at Hospital Discharge in Patients Achieving Return of Spontaneous Circulation (ROSC) After IHCA: an Observational Study

https://doi.org/10.21203/rs.3.rs-5329237/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Background: Moderate overweight in hospital cardiac arrest (IHCA) patients tend to have better neurological outcomes after attaining return of spontaneous circulation (ROSC), but the underlying mechanism has not been elucidated.

Method: We collected the demographics, clinical and cardiac arrest characteristics, thoracic cage dimension indexes measured from computed tomography (CT) images, and survival and neurological outcome at hospital discharge of the eligible patients. Patients receiving different kind of respiratory support while performing pre-compression and post-compression CT scans were divided into groups and we did the subgroup analysis.

Results: We reviewed the clinical records of 1663 CA patients. After selection, 70 patients were included into this study. We found thicker posterior SAT (pSAT) at the 7/8/10/11 spinous process plane in patients with favorable neurological outcome in post-compression CT images(p<0.05). For patients with favorable neurological outcome receiving one kind of respiratory support during peri-cardiac arrest period, we found significantly thicker pSAT at the 6/7/8/9/10/11 spinous process plane in pre-compression and 7/8/9/10/11/12 spinous plane in post-compression CT images (p<0.05). Patients with favorable neurological outcome receiving mechanical ventilation (MV) in peri-cardiac arrest period had thicker pSAT at the 10/11/12 spinous process plane; for those without MV, thicker pSATs were found at 10/11 spinous process plane in post-compression CT images(p<0.05). We found no difference in bony thorax within different vertebral plane after subgroup analysis (p>0.05).

Conclusion: Thicker posterior SAT depth during peri-cardiac arrest period is associated with favorable neurological outcome at discharge for IHCA survivors. This could partly explain the “obese paradox” that overweight patients have better prognosis after CA. We recommend a multiple vertebral plane thorax measurement for future investigations concerning chest characteristics.

In-hospital cardiac arrest

Neurological outcome

Subcutaneous Adipose Tissue

Thoracic cage

Chest compression (CC) poses as the core of cardiopulmonary resuscitation (CPR) ^{[1, 2]}. Based on the cardiac pump theory, researchers have found that animal chests will deform under the forces applied between nipples, subsequently, blood will circulate in vivo ^[3–6]. During this procedure, subcutaneous adipose tissue (SAT) and bony thorax serve as the bridge between external forces and body perfusion, and could possibly affect the efficacy of CPR or outcome of CA patients in retrospective findings or theoretical model ^{[7, 8]}. We could possibly accept that patients with small thorax and thinner posterior SAT will survive after CPR and have more promising future for survival^[7]. Paradoxically, moderately overweight CA patients generally have more favorable neurological outcome in few meta-analysis^[9–11], while obese patients tend to have thicker SAT and the efficacy of the CC could be undermined^[8].

To find the possible explanation for “obese paradox”, we paid attention to patients who survived the peri-cardiac arrest period with CT images before CA and acquired another CT scan after CPR. We extracted those patients’ chest characteristic from T3-12 vertebral level and compared short-term prognosis within survivors and non-survivors, and patients with different neurological outcome.

The aim of the study is to find out the association between short-term prognosis and deformation of adult thorax for patients acquired return of spontaneous circulation (ROSC) following CPR. We hypothesized that chest SAT layers might offer protection for CA survivors.

Study design, setting and population

A retrospective cohort study was conducted in the emergency department (ED) of West China Hospital, Sichuan University. Adult patients (≥ 18 years old) with recorded IHCA and achieved sustained ROSC during May 31, 2019 to June 30, 2021 with documented CT images before and after CPR were enrolled in the study. We excluded patients with severe thoracic trauma, thoracic deformity due to enduring lung diseases, congenital thoracic deformity, thoracotomy, inconsistent posture while performing two CT scans, pregnancy, and missing data. All procedures were performed in compliance with laws and were approved by the Human Ethical Committee of West China Hospital (number: 2021,1557).

Outcomes

The outcomes of interest were survival and favorable neurological outcome at hospital discharge. Definitions of the outcomes were based on the Ustein template. Neurological outcomes were assessed using the cerebral performance category (CPC) scale ^[12].

Data collection

Patient characteristics, baseline data, timepoints of each CT scan and endotracheal intubation, and data related to the event were collected using medical records and event protocols. As for the strictly aforementioned inclusion criteria, we accumulated and analyzed the intubation and event data during two CT scans of all patients besides the data during inpatient. Multidetector CT examinations were performed with Philips Brilliance 16-slice MDCT (Philips Healthcare, Cleveland, Ohio) with a 5-mm slice thickness. Unenhanced cross-sectional CT images were then analyzed via the three-dimensional visualization software (Mimics Interactive Medical Image Control System, Version 17.0, Materialize Company, Belgium). All images were imported to the software and patient’s thoracic cage was reconstructed to accurately localize T3-T12 vertebra and spinous process for further measurement (Fig. 1).

Thoracic cage dimension indexes including the transverse diameter (TD) (the shortest distance between the sternal notch and vertebrae), internal anteroposterior diameter (AD) (the maximal horizontal distance of the inside of the rib cage), and cross-sectional area (CsA) ^[7] were measured at T3-12 vertebral level, Haller index (HI) was calculated as is defined as the ratio of the TD of the chest and the AD of the chest^{[13, 14]}.

SAT depths including anterior subcutaneous adipose tissue depth (aSAT) and posterior subcutaneous adipose tissue depth (pSAT) either in pre-compression or post-compression CT images were measured at T3-12 spinous process level.

Subgroup division

We divided all eligible cases into three subgroups given that positive mechanical ventilation could affect lung capacity^[15]: patients with or without mechanical ventilation were divided into different groups and analyzed. Group N-1 included patients without mechanical ventilation while performing two CT scans; group N-2 was for patients under positive mechanical ventilation while performing two CT scans; group N-3 was set up for patients with different ventilation modes (once for positive and once for none) at two timepoint of CT scans. As for survival analysis, all eligible patients were divided into group S-1, S-2 and S-3, as appropriate.

Statistical analyses

Continuous data were expressed as mean standard ± deviation or median and interquartile, categorical data were presented as counts with frequencies. Normally distributed continuous variables were compared by student t-test, while repeated measured thorax dimensions were compared with two-way ANOVA (for patients with same kind of ventilation mode while performing two CT scans), skewed distributed continued variables were compared by Mann–Whitney U test. Categorical variables were compared by chi-square test. A two-sided p value < 0.05 was considered statistically significant. All analyses were conducted using SPSS statistical software version 24.0 (IBM Corporation, Armonk, NY).

Overview

A total of 1663 patients who experienced IHCA between May 31, 2019 to June 30, 2021 were identified, of which 60 patients also experienced OHCA prior to admission; 1503 patients were not eligible since there were no available CT images. Subsequently, 100 patients reach the inclusion criteria after screening. Among them, 21 patients were excluded because of thoracotomy before either CT scan, another 5 patients were excluded with severe rib or sternum fracture due to thoracic trauma. Two patients suffered from enduring lung diseases whose dimensions could not be compared. One patient changed posture when receiving the post-compression CT scans (Additional file 4, Fig S1) and one patient had congenital thoracic deformity. Thus, the final cohort included 70 patients (Fig. 2).

Patient characteristics

Patient baseline characteristics are presented in Table 1. There was no difference between survivors and non-survivors on age, BMI, initial rhythm, and commodities. Patients with favorable neurological outcome were characterized by a higher proportion of neurological insufficiency compared to patients with unfavorable neurological outcome (p = 0.261). Under this circumstance, patients with neurological insufficiency were further extracted from the cohort when neurological outcome at discharge was analyzed.

Table 1

Patient baseline characteristics
Variables	All patients (n = 70)			Outcome
Variables	All patients (n = 70)	Survivors (n = 56)	Non-survivors (n = 14)	p Value	Favorable neurological outcome (n = 32)	Unfavorable neurological outcome (n = 38)	p Value
Age(y) (mean ± SD† )	56.19 ± 17.47	54.31 ± 16.6	63.07 ± 19.43	0.085	51.81 ± 18.14	59.84 ± 16.21	0.054
Male (%)	49 (70.0%)	39(70.9%)	10(66.7%)	0.490	23 (71.9%)	26(68.4%)	0.753
BMI	23.09 ± 4.43	23.06 ± 4.52	23.19 ± 4.25	0.919	23.51 ± 4.58	22.73 ± 4.34	0.472
Initial rhythm- Shockable	15(21.4%)	10(18.2%)	5(33.3%)	0.179	10(31.3%)	5(13.2%)	0.066
Commodities
Heart disease (n, %)	11(15.7%)	8(14.5%)	3(20.0%)	0.691	8(25.0%)	3(7.9%)	0.096
Respiratory insufficiency (n, %)	15 (21.4%)	12(21.8%)	3(20.0%)	0.879	8 (25.0%)	7(18.4%)	0.504
Neurological insufficiency (n, %)	12(17.1%)	7(12.7%)	5(33.3%)	0.114	2(6.3%)	10(26.3%)	0.026*
Gastrointestinal disease (n, %)	7(10.0%)	6(10.9%)	1(6.7%)	0.627	2(6.3%)	5(13.2%)	0.442
Renal insufficiency (n, %)	1(1.4%)	1(1.8%)	0	0.786	1(3.1%)	0	0.457
Sepsis‡ (n, %)	11(15.7%)	10(18.2%)	1(6.7%)	0.435	3(9.4%)	8(21.1%)	0.181
Metastatic malignancy (n, %)	5(7.1%)	3(5.5%)	2(13.3%)	0.290	0	5(13.2%)	0.058
poisoning (n, %)	1(1.4%)	1(1.8%)	0	0.786	1(3.1%)	0	0.457
Abbreviations: †standard deviation;
‡Includes patients diagnosed with septic shock.

Table 1 should appear here, is placed at the end of the manuscript due to large size.

Event characteristics

The median number of cardiac arrests during inpatient was once among all patients, and the median time of CPR was 6 minutes. Intubation rate of all patients was 92.9%, for survivors and non-survivors, there was no significant difference between them in the timepoint of intubation.

For patients with favorable neurological outcome, fewer patients intubated before CA, while the intubation rate during inpatient was not significantly different between patients with unfavorable neurological outcome. (Additional file 1, Table S1-4)

CT scan timepoints and event index during intervals

The median time interval between the recorded CT and the first CA of all patients was 2.84 days; while the interval of ROSC and the first rechecked CT had a median day of 6.35, which was of no significant difference between survivors and non-survivors. When groups by neurological outcome at discharge, there was no significance, either. (Supplementary1, Table S5-6)

Cardiac arrest indexes among patients with different outcome during CT interval were not significantly different. (Additional file1, Table S7-8)

Bony thorax and outcomes

No significant difference was found in TD, AD, CsA or HI at different vertebral level within patients with different outcome in pre-compression or post-compression CT images. Subgroup analysis showed no significant difference (Additional file 2, Table 3–6, 9–12; Additional file 3, Table 3–6, 9–12)

SATs and outcomes

For the analysis of survival of patients at discharge, no significant difference was found for aSATs or pSATs in all patients or subgroup analysis. (Additional file 2, 3)

Patients with favorable neurological outcome had significantly thicker pSATs at the 7/8/10/11 spinous process level than in group of poor neurological prognosis in post-compression CT images after excluding patients with neurological insufficiency at admission (p < 0.05) (Table 2). Patients received same kind of respiratory support in two CT scans (Group N-1 + Group N-2) were therefore analyzed to eliminate the disturbance of ventilation on chest indexes. Among them, significantly thicker pSATs were found at the 6/7/8/9/10/11 spinous process level in patients with favorable neurological prognosis in pre-compression CT images (p < 0.05) (Additional file 3, Table 2); pSATs were significantly thicker in post-compression CT images at the 7/8/9/10/11/12 spinous process level in patients with favorable neurological prognosis than in group of poor neurological prognosis(p < 0.05) (Additional file 3, Table 8). Notably, worse outcome was associated with significant reduction of pSATs at 8/10/11 spinous process level, indicating the consumption of adipose tissue during peri-arrest period. (Fig. 3) Subgroup analysis was further conducted to explore the relationship between SATs and neurological prognosis. For patients in N-1, significantly thicker pSAT post-compression was found at the 10/11 spinous process level in patients with favorable neurological outcome(p < 0.05). Significantly thicker posterior SAT post-compression was found at the 10/11/12 spinous plane in patients with favorable neurological prognosis in N-2 (p < 0.05).

When aSATs were compared, no significant difference was found at different spinous process level within patients with different neurological prognosis in pre-compression or post-compression CT images neither in all studied patients or any subgroups.

Table 2 - Posterior SAT depth in each spinous process level measured among patients with different outcome at discharge in post-compression CT images

pSAT(mm) (mean±SD)	Favorable neurological outcome (n=30)	Unfavorable neurological outcome (n=28)	p value
T3	22.31±10.89	19.98±9.10	0.404
T4	20.70±9.53	18.63±7.89	0.383
T5	20.45±8.26	17.05±7.09	0.103
T6	19.48±9.08	15.95±5.86	0.086
T7	18.94±9.03	14.97±5.52	0.050*
T8	18.65±9.10	14.40±5.76	0.038*
T9	19.20±9.67	15.07±6.45	0.063
T10	19.19±9.64	14.40±6.96	0.035*
T11	19.19±9.98	14.33±7.54	0.047*
T12	17.58±9.58	14.80±8.52	0.309

Abbreviations: pSAT,posterior subcutaneous adipose tissue depth; SD, standard deviation

The main finding of our study is that patients with thicker chest pSATs generally have more favorable neurological outcome, when compared either before CA or after chest compression within peri-arrest period. Thicker pSATs depth could partly account for the “obese paradox” that overweight patients have better prognosis after CA. In this study cohort, the median time of CPR is 6 minutes, we also found non-calculatable difference of the chest bony index during peri-arrest period within the small group of patients of different short-term outcome at discharge.

Various study cohort uncovered different short-term outcome for IHCA patients. In the American Heart Association’s Get With The Guidelines Resuscitation (GWTG-R) registry, survival to hospital discharge was reported to be 25%^[16], with 24% survivors had CPC score less than or equal to 2 from 2001 to 2017 ^[17]. In Japan, survival to discharge was 14.0% in 2017^[18]. One previous study enrolled patients with chest CT images before IHCA, the survival rate of the patients was 16.5%^[7]. In this study cohort, all patients acquired sustained ROSC after CA, 80% patients survived to discharge with the median days from CA to discharge was 21.6 days, more than half (54.2%) survivors were discharged from hospital with favorable neurological outcome. Given the limited data of the thoracic characteristics for ROSC patients receiving advanced life support (ALS) in the intensive care unit (ICU), we assert that patients in our study could represent those who have more promising prognosis after CPR and give insights for the practitioners who face with the dilemma of withdrawn of life for patients with unfavorable neurological outcome.

BMI is paradoxically corelated with the prognosis of CA patients. Overweight (25.0 ≤ BMI < 30.0 kg/m²) OHCA patients had lower hospital all-cause mortality and had more favorable neurological outcome than normal weight (28.5 ≤ BMI < 24.9 kg/m²), underweight (BMI < 18.5 kg/m²), and obese (BMI≥30 kg/m²) CA patients^[9]. Another meta-analysis indicated that underweight was associated with higher hospital mortality among OHCA and IHCA patients, while overweight patients had higher survival rate and better neurological recovery ^[10]. But higher BMI (BMI>23.2 kg/m²) and external thoracic anteroposterior diameter (EPAD) were inversely associated favorable neurological outcome within IHCA patients ^[19]. The obesity paradox applies to the post-arrest population, higher BMI was associated with lower all-cause mortality during a median follow-up of 3.6 years^[11] and six-month neurological recovery ^[20] among CA survivors. Previous studies have provided limited information on the exact mechanism of higher BMI protection of CA patients. From our prospective, moderate overweight patients might had greater tolerance of post cardiac arrest syndrome (PCAS), but thicker pSATs protect patients’ inner organ from the impact of chest compression. In previous research, we did not find the direct correlation between BMI and depth of SATs either in CA patients or healthy adults. BMI is linearly correlated with pSAT in patients with diagnosis of obesity or morbid obesity (mean BMI 45.95 kg/m²) skin surface and the sternum at the 4th costal cartilage anteriorly and the skin surface and the tip of the 3rd spinous process posteriorly, reported by Secombe et al. ^[8]. For adults screening in health checkup centers, SAT areas measured at the center of the 2nd lumbar vertebra were positively associated with BMI and waist circumference in every age group. Our work didn’t find out the difference of BMI between groups, so we attributed “obese protection” to pSATs rather than BMI. And our results are not contradictory to previous finding that IHCA patients with smaller pSAT depth are associated with better short-term survival, which could be explained by more adequate blood perfusion and better compression efficacy. We paid attention to survivors and tried to explain the favorable neurological outcome within peri-arrest period.

Patients with smaller thoracic cage are easier to acquire adequate compression depth and thoracic cage compression ratio, leading greater intrathoracic pressure and better systemic blood perfusion under same chest compression maneuver ^[7]. We didn’t find any study comparing chest dimension twice during peri-cardiac arrest period, and whether the thorax will deform after CPR has not been studied, either. Our work did not reveal any difference in bony thorax dimension (TD, AD, CsA), and shape (HI) between survivors and non-survivors, and patients of different neurological recovery.

Several confounding factors could possibly affect thoracic cage dimension measurements. Firstly, anatomical structure of the fourth intercostal plane varies among different individuals ^[21] (Additional file 4, Fig S2). Secondly, positive mechanically ventilated patients were unable to synchronize with CT scanning instructions, so the images were randomly captured during either inspiration or expiration. Thirdly, the level of positive end-expiratory pressure (PEEP) could influence end-expiratory lung volume (EELV) ^[15]. Accordingly, we divided patients with different respiratory support when conducting the needed two chest scanning into different subgroups and innovatively measure the whole thorax from different spinous process and vertebral level to offset the effect of individual anatomical variation and mechanical ventilation, and surprisingly, CA patients with favorable neurological outcome in different subgroups had thicker pSATs in lower spinous process level either compared before or after chest compression.

Limitations

First, a major limitation was the single-center design and strict inclusion criteria. A large amount of CA patients of cardiac origin were not included for not receiving CT scan before CPR. Most of them are shockable rhythm and obtained ROSC soon after defibration, the results could not be generalized to those patients. Moreover, we could not conclude that pSAT depth is an independent risk factor for CA patients with unfavorable neurological prognosis at discharge limited by the sample size, but our study provide insight for further investigation. Lastly, mechanical ventilation could partly affect the results, thus we did not conduct subgroup analysis for patients in group S-3 or N-3. Further prospective study could include patients under same ventilatory settings to possibly eliminate this confounder.

Thicker posterior SAT depth during peri-cardiac arrest period is associated with favorable neurological outcome at discharge for IHCA survivors. Thicker pSATs depth could partly explain the “obese paradox” that overweight patients have better prognosis after CA. We strongly recommend a multiple vertebral level thorax measurement for in future studies of chest dimensions and CA patients’ prognosis rather than just the 4th intercostal space level.

Acknowledgements

We sincerely thank Xia Guo from Sichuan University for her recommendations of scientific writing.

Funding

This project was supported by National Natural Science Foundation of China (82072135 and 82272241), and China Postdoctoral Science Foundation (2023M732462).

Author information

Authors and Affiliations

Sichuan University-The Hong Kong Polytechnic University Institute for Disaster Management and Reconstruction, Chengdu, China.

Tingyuan Zhou, Wen Ma

Department of Emergency Medicine, Institute of Disaster Medicine and Institute of Emergency Medicine, West China Hospital, Sichuan University, China.

Tingyuan Zhou, Wen Ma, Yarong He, Songling Tang, Mengyao Jian, Peng Yao and Yu Cao

West China School of Medicine, West China Hospital, Sichuan University

Songling Tang, Mengyao Jian

Contributions

TZ and WM conceptualized and designed the study, collected the data, carried out analyses, drafted the manuscript, revised the final manuscript. YH revised the manuscript and assisted the data collection. ST and MJ extracted the data from CT images and did the initial analysis. YC supervised the data collection, analysis and overall study. PY and YC obtained the research funding. All authors read and approved the final manuscript as submitted, and agree to be responsible for all aspects of the work.

Corresponding author

Correspondence to Yu Cao.

Ethics declarations

Ethics approval and consent to participate

The study was performed in compliance with laws and were approved by the Human Ethical Committee of West China Hospital (number: 2021,1557).

Consent for publication

Not applicable

Competing interests

This abstract was presented orally in WACEM22&TOPCOM22, 18th November 2022, and presented with poster in WADEM, 11th May, 2023 in Killarney, Ireland.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Nolan Jerry P., Maconochie Ian, Soar Jasmeet, Olasveengen Theresa M., Greif Robert, Wyckoff Myra H., et al. Executive Summary 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. Resuscitation 2020; 156: A1-A22.https://doi.org/10.1016/j.resuscitation.2020.09.009
Orlob S., Kern W. J., Alpers B., Schörghuber M., Bohn A., Holler M., et al. Chest compression fraction calculation: A new, automated, robust method to identify periods of chest compressions from defibrillator data - Tested in Zoll X Series. Resuscitation 2022; 172: 162-9.
Prinzing A., Eichhorn S., Deutsch M. A., Lange R., Krane M. Cardiopulmonary resuscitation using electrically driven devices: a review. Journal of thoracic disease 2015; 7: E459-67.
Porter T. R., Ornato J. P., Guard C. S., Roy V. G., Burns C. A., Nixon J. V. Transesophageal echocardiography to assess mitral valve function and flow during cardiopulmonary resuscitation. The American journal of cardiology 1992; 70: 1056-60.
Liu P., Gao Y., Fu X., Lu J., Zhou Y., Wei X., et al. Pump models assessed by transesophageal echocardiography during cardiopulmonary resuscitation. Chinese medical journal 2002; 115: 359-63.
Cipani S., Bartolozzi C., Ballo P., Sarti A. Blood flow maintenance by cardiac massage during cardiopulmonary resuscitation: Classical theories, newer hypotheses, and clinical utility of mechanical devices. Journal of the Intensive Care Society 2019; 20: 2-10.
Liu J. Z., Ye S., Cheng T., Han T. Y., Li Q., Li R. X., et al. The effects of thoracic cage dimension and chest subcutaneous adipose tissue on outcomes of adults with in-hospital cardiac arrest: A retrospective study. Resuscitation 2019; 141: 151-7.
Secombe P., Sutherland R., Johnson R. Body mass index and thoracic subcutaneous adipose tissue depth: possible implications for adequacy of chest compressions. BMC research notes 2017; 10: 575.
Kakavas S., Georgiopoulos G., Oikonomou D., Karayiannis D., Masi S., Karlis G., et al. The impact of body mass index on post resuscitation survival after cardiac arrest: A meta-analysis. Clinical nutrition ESPEN 2018; 24: 47-53.
Ma Y., Huang L., Zhang L., Yu H., Liu B. Association between body mass index and clinical outcomes of patients after cardiac arrest and resuscitation: A meta-analysis. Am J Emerg Med 2018; 36: 1270-9.
Matinrazm S., Ladejobi A., Pasupula D. K., Javed A., Durrani A., Ahmad S., et al. Effect of body mass index on survival after sudden cardiac arrest. Clinical cardiology 2018; 41: 46-50.
Perkins G. D., Jacobs I. G., Nadkarni V. M., Berg R. A., Bhanji F., Biarent D., et al. Cardiac arrest and cardiopulmonary resuscitation outcome reports: update of the Utstein Resuscitation Registry Templates for Out-of-Hospital Cardiac Arrest: a statement for healthcare professionals from a task force of the International Liaison Committee on Resuscitation (American Heart Association, European Resuscitation Council, Australian and New Zealand Council on Resuscitation, Heart and Stroke Foundation of Canada, InterAmerican Heart Foundation, Resuscitation Council of Southern Africa, Resuscitation Council of Asia); and the American Heart Association Emergency Cardiovascular Care Committee and the Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation. Circulation 2015; 132: 1286-300.
Daunt S. W., Cohen J. H., Miller S. F. Age-related normal ranges for the Haller index in children. Pediatric radiology 2004; 34: 326-30.
Archer J. E., Gardner A., Berryman F., Pynsent P. The measurement of the normal thorax using the Haller index methodology at multiple vertebral levels. Journal of anatomy 2016; 229: 577-81.
Piraino T. Lung Volume Measurement and Ventilation Distribution During Invasive Mechanical Ventilation. Respiratory care 2020; 65: 760-71.
Andersen L. W., Holmberg M. J., Berg K. M., Donnino M. W., Granfeldt A. In-Hospital Cardiac Arrest: A Review. Jama 2019; 321: 1200-10.
Mayampurath Anoop, Hagopian Raffi, Venable Laura, Carey Kyle, Edelson Dana, Churpek Matthew, et al. Comparison of Machine Learning Methods for Predicting Outcomes After In-Hospital Cardiac Arrest. Critical care medicine 2022; 50: https://journals.lww.com/ccmjournal/Fulltext/2022/02000/Comparison_of_Machine_Learning_Methods_for.31.aspx
Ohbe H., Tagami T., Uda K., Matsui H., Yasunaga H. Incidence and outcomes of in-hospital cardiac arrest in Japan 2011-2017: a nationwide inpatient database study. Journal of intensive care 2022; 10: 10.
Wang C. H., Huang C. H., Chang W. T., Fu C. M., Wang H. C., Tsai M. S., et al. Associations between body size and outcomes of adult in-hospital cardiac arrest: A retrospective cohort study. Resuscitation 2018; 130: 67-72.
Testori C., Sterz F., Losert H., Krizanac D., Haugk M., Uray T., et al. Cardiac arrest survivors with moderate elevated body mass index may have a better neurological outcome: a cohort study. Resuscitation 2011; 82: 869-73.
Pickard A., Darby M., Soar J. Radiological assessment of the adult chest: implications for chest compressions. Resuscitation 2006; 71: 387-90.

No competing interests reported.

Additionalfile1.docx
Supplementary Information Additional file 1 illustrated the detailed information of the included patients receiving medical care.
Additionalfile2.docx
Additional file 2 and 3 gave all CT scan comparison between groups.
Additionalfile3.docx
Additional file 2 and 3 gave all CT scan comparison between groups.
Additionalfile4.docx
Additional file 4 showed some accidental findings during the research.

Download PDF

Version 1

posted

You are reading this latest preprint version

Thicker Posterior Subcutaneous Adipose Tissue (SAT) During Peri-arrest Period is Associated Favorable Neurological Outcome at Hospital Discharge in Patients Achieving Return of Spontaneous Circulation (ROSC) After IHCA: an Observational Study

Status:

Version 1

Abstract

Figures

Introduction

Methods

Results

Discussion

Conclusion

Declarations

References

Additional Declarations

Supplementary Files

Status:

Version 1