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Continuous noninvasive blood gas estimation in critically ill pediatric patients with respiratory failure. Sci Rep 2022; 12:9853. [PMID: 35701446 PMCID: PMC9198060 DOI: 10.1038/s41598-022-13583-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 05/25/2022] [Indexed: 11/09/2022] Open
Abstract
Patients supported by mechanical ventilation require frequent invasive blood gas samples to monitor and adjust the level of support. We developed a transparent and novel blood gas estimation model to provide continuous monitoring of blood pH and arterial CO2 in between gaps of blood draws, using only readily available noninvasive data sources in ventilated patients. The model was trained on a derivation dataset (1,883 patients, 12,344 samples) from a tertiary pediatric intensive care center, and tested on a validation dataset (286 patients, 4030 samples) from the same center obtained at a later time. The model uses pairwise non-linear interactions between predictors and provides point-estimates of blood gas pH and arterial CO2 along with a range of prediction uncertainty. The model predicted within Clinical Laboratory Improvement Amendments of 1988 (CLIA) acceptable blood gas machine equivalent in 74% of pH samples and 80% of PCO2 samples. Prediction uncertainty from the model improved estimation accuracy by 15% by identifying and abstaining on a minority of high-uncertainty samples. The proposed model estimates blood gas pH and CO2 accurately in a large percentage of samples. The model's abstention recommendation coupled with ranked display of top predictors for each estimation lends itself to real-time monitoring of gaps between blood draws, and the model may help users determine when a new blood draw is required and delay blood draws when not needed.
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Zaky S, Fathelbab HK, Elbadry M, El-Raey F, Abd-Elsalam SM, Makhlouf HA, Makhlouf NA, Metwally MA, Ali-Eldin F, Hasan AA, Alboraie M, Yousef AM, Shata HM, Eid A, Asem N, Khalaf A, Elnady MA, Elbahnasawy M, Abdelaziz A, Shaltout SW, Elshemy EE, Wahdan A, Hegazi MS, Abdel Baki A, Hassany M. Egyptian Consensus on the Role of Lung Ultrasonography During the Coronavirus Disease 2019 Pandemic. Infect Drug Resist 2022; 15:1995-2013. [PMID: 36176457 PMCID: PMC9513721 DOI: 10.2147/idr.s353283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 03/28/2022] [Indexed: 12/05/2022] Open
Abstract
Background & Aims Coronavirus disease 2019 (COVID-19) is a global health problem, presenting with symptoms ranging from mild nonspecific symptoms to serious pneumonia. Early screening techniques are essential in the diagnosis and assessment of disease progression. This consensus was designed to clarify the role of lung ultrasonography versus other imaging modalities in the COVID-19 pandemic. Methods A multidisciplinary team consisting of experts from different specialties (ie, pulmonary diseases, infectious diseases, intensive care unit and emergency medicine, radiology, and public health) who deal with patients with COVID-19 from different geographical areas was classified into task groups to review the literatures from different databases and generate 10 statements. The final consensus statements were based on expert physically panelists’ discussion held in Cairo July 2021 followed by electric voting for each statement. Results The statements were electronically voted to be either “agree,” “not agree,” or “neutral.” For a statement to be accepted to the consensus, it should have 80% agreement. Conclusion Lung ultrasonography is a rapid and useful tool, which can be performed at bedside and overcomes computed tomography limitations, for screening and monitoring patients with COVID-19 with an accepted accuracy rate.
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Affiliation(s)
- Samy Zaky
- Department of Hepatogastroenterology and Infectious Diseases; Al-Azhar University, Cairo, Egypt
| | | | - Mohamed Elbadry
- Department of Endemic Medicine, Helwan University, Cairo, Egypt
| | - Fathiya El-Raey
- Department of Hepatogastroenterology and Infectious Diseases Al-Azhar University, Damietta, Egypt
| | - Sherief M Abd-Elsalam
- Department of Tropical Medicine, Tanta University, Tanta, Egypt
- Correspondence: Sherief M Abd-Elsalam, Department of Tropical Medicine, Tanta University, Tanta, Egypt, Tel +201063319696, Email
| | | | - Nahed A Makhlouf
- Department of Tropical Medicine and Gastroenterology, Assiut University, Assiut, Egypt
| | - Mohamed A Metwally
- Department of Hepatology, Gastroenterology, and Infectious Diseases, Benha University, Benha, Egypt
| | - Fatma Ali-Eldin
- Department of Tropical medicine; Ain Shams University, Cairo, Egypt
| | | | - Mohamed Alboraie
- Department of Internal Medicine; Al-Azhar University, Cairo, Egypt
| | - Ahmed M Yousef
- Department of Community and Industrial Medicine, Damietta, Al-Azhar University, Damietta, Egypt
| | - Hanan M Shata
- Department of Chest Medicine; Mansoura University, Mansoura, Egypt
| | - Alshaimaa Eid
- Department of Hepatogastroenterology and Infectious Diseases; Al-Azhar University, Cairo, Egypt
| | - Noha Asem
- Department of Public Health and Community Medicine, Cairo University and Ministry of Health and Population, Cairo, Egypt
| | - Asmaa Khalaf
- Department of Radiology, Minia University, Minia, Egypt
| | - Mohamed A Elnady
- Department of Pulmonary Medicine, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mohamed Elbahnasawy
- Department of Emergency Medicine and Traumatology, Tanta University, Tanta, Egypt
| | - Ahmed Abdelaziz
- Department of Hepatogastroenterology and Infectious Diseases Al-Azhar University, Damietta, Egypt
| | - Shaker W Shaltout
- Department of Tropical Medicine, Port Said University, Port Said, Egypt
| | - Eman E Elshemy
- Department of Hepatogastroenterology and Infectious Diseases; Al-Azhar University, Cairo, Egypt
| | - Atef Wahdan
- Department of Chest Diseases, Damietta, Al-Azhar University, Damietta, Egypt
| | - Mohamed S Hegazi
- Department of Hepatogastroenterology and Infectious Diseases Al-Azhar University, Damietta, Egypt
| | - Amin Abdel Baki
- Department Hepatology, Gastroenterology and Infectious diseases National Hepatology and Tropical Medicine Research Institute NHTMRI, Cairo, Egypt
| | - Mohamed Hassany
- Department Hepatology, Gastroenterology and Infectious diseases National Hepatology and Tropical Medicine Research Institute NHTMRI, Cairo, Egypt
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Malarvili MB, Alexie M, Dahari N, Kamarudin A. On Analyzing Capnogram as a Novel Method for Screening COVID-19: A Review on Assessment Methods for COVID-19. Life (Basel) 2021; 11:1101. [PMID: 34685472 PMCID: PMC8538964 DOI: 10.3390/life11101101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/12/2021] [Accepted: 10/12/2021] [Indexed: 12/15/2022] Open
Abstract
In November 2019, the novel coronavirus disease COVID-19 was reported in Wuhan city, China, and was reported in other countries around the globe. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Strategies such as contact tracing and a vaccination program have been imposed to keep COVID-19 under control. Furthermore, a fast, noninvasive and reliable testing device is needed urgently to detect COVID-19, so that contact can be isolated and ringfenced before the virus spreads. Although the reverse transcription polymerase chain reaction (RT-PCR) test is considered the gold standard method for the diagnosis of SARS-CoV-2 infection, this test presents some limitations which cause delays in detecting the disease. The antigen rapid test (ART) test, on the other hand, is faster and cheaper than PCR, but is less sensitive, and may limit SARS-CoV-2 detection. While other tests are being developed, accurate, noninvasive and easy-to-use testing tools are in high demand for the rapid and extensive diagnosis of the disease. Therefore, this paper reviews current diagnostic methods for COVID-19. Following this, we propose the use of expired carbon dioxide (CO2) as an early screening tool for SARS-CoV-2 infection. This system has already been developed and has been tested on asthmatic patients. It has been proven that expired CO2, also known as capnogram, can help differentiate between respiratory conditions and, therefore, could be used to detect SARS-CoV-2 infection, as it causes respiratory tract-related diseases.
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Affiliation(s)
- M. B. Malarvili
- School of Biomedical and Health Science Engineering, Universiti Teknologi Malaysia, Skudai, Johor Bahru 81310, Malaysia; (M.A.); (N.D.)
| | - Mushikiwabeza Alexie
- School of Biomedical and Health Science Engineering, Universiti Teknologi Malaysia, Skudai, Johor Bahru 81310, Malaysia; (M.A.); (N.D.)
- College of Science and Technology (CST), Center or Excellence in Biomedical Engineering and E-Health (CEBE), University of Rwanda, KN 67 Street Nyarugenge, Kigali 3900, Rwanda
| | - Nadhira Dahari
- School of Biomedical and Health Science Engineering, Universiti Teknologi Malaysia, Skudai, Johor Bahru 81310, Malaysia; (M.A.); (N.D.)
| | - Anhar Kamarudin
- Faculty of Medicine, University Malaya Medical Centre (UMMC), Kuala Lumpur 59100, Malaysia;
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Bachmann KF, Vasireddy R, Heinisch PP, Jenni H, Vogt A, Berger D. Estimating cardiac output based on gas exchange during veno-arterial extracorporeal membrane oxygenation in a simulation study using paediatric oxygenators. Sci Rep 2021; 11:11528. [PMID: 34075067 PMCID: PMC8169686 DOI: 10.1038/s41598-021-90747-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 05/17/2021] [Indexed: 11/29/2022] Open
Abstract
Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy is a rescue strategy for severe cardiopulmonary failure. The estimation of cardiac output during VA-ECMO is challenging. A lung circuit (\documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung) and an ECMO circuit (\documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V./\documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙) ratios and shunt. A metabolic chamber with a CO2/N2 blend simulated \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO2 and \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O2. \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung was estimated with a modified Fick principle: \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung = \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙ECMO × (\documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V. CO2 or \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O2Lung)/(\documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO2 or \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O2ECMO). A normalization procedure corrected \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO2 values for a \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V./\documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙ of 1. Method agreement was evaluated by Bland–Altman analysis. Calculated \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung using gaseous \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO2 and \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O2 correlated well with measured \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung with a bias of 103 ml/min [− 268 to 185] ml/min; Limits of Agreement: − 306 ml/min [− 241 to − 877 ml/min] to 512 ml/min [447 to 610 ml/min], r2 0.85 [0.79–0.88]). Blood measurements of \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.CO2 showed an increased bias (− 260 ml/min [− 1503 to 982] ml/min), clinically not applicable. Shunt and \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙ mismatch decreased the agreement of methods significantly. This in-vitro simulation shows that \documentclass[12pt]{minimal}
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\begin{document}$$\mathop {\text{V}}\limits^{.}$$\end{document}V.O2 in steady-state conditions allow for clinically applicable calculations of \documentclass[12pt]{minimal}
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\begin{document}$${\dot{\text{Q}}}$$\end{document}Q˙Lung during VA-ECMO therapy.
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Affiliation(s)
- Kaspar Felix Bachmann
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland. .,Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| | - Rakesh Vasireddy
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Paul Philipp Heinisch
- Department of Cardiac and Vascular Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Congenital and Pediatric Heart Surgery, German Heart Center Munich, Technische Universität München, Munich, Germany
| | - Hansjörg Jenni
- Department of Cardiac and Vascular Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Andreas Vogt
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - David Berger
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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Bachmann KF, Haenggi M, Jakob SM, Takala J, Gattinoni L, Berger D. Gas exchange calculation may estimate changes in pulmonary blood flow during veno-arterial extracorporeal membrane oxygenation in a porcine model. Am J Physiol Lung Cell Mol Physiol 2020; 318:L1211-L1221. [PMID: 32294391 PMCID: PMC7276983 DOI: 10.1152/ajplung.00167.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is used as rescue therapy for severe cardiopulmonary failure. We tested whether the ratio of CO2 elimination at the lung and the V-A ECMO (V̇co2ECMO/V̇co2Lung) would reflect the ratio of respective blood flows and could be used to estimate changes in pulmonary blood flow (Q̇Lung), i.e., native cardiac output. Four healthy pigs were centrally cannulated for V-A ECMO. We measured blood flows with an ultrasonic flow probe. V̇co2ECMO and V̇co2Lung were calculated from sidestream capnographs under constant pulmonary ventilation during V-A ECMO weaning with changing sweep gas and/or V-A ECMO blood flow. If ventilation-to-perfusion ratio (V̇/Q̇) of V-A ECMO was not 1, the V̇co2ECMO was normalized to V̇/Q̇ = 1 (V̇co2ECMONorm). Changes in pulmonary blood flow were calculated using the relationship between changes in CO2 elimination and V-A ECMO blood flow (Q̇ECMO). Q̇ECMO correlated strongly with V̇co2ECMONorm (r2 0.95–0.99). Q̇Lung correlated well with V̇co2Lung (r2 0.65–0.89, P < = 0.002). Absolute Q̇Lung could not be calculated in a nonsteady state. Calculated pulmonary blood flow changes had a bias of 76 (−266 to 418) mL/min and correlated with measured Q̇Lung (r2 0.974–1.000, P = 0.1 to 0.006) for cumulative ECMO flow reductions. In conclusion, V̇co2 of the lung correlated strongly with pulmonary blood flow. Our model could predict pulmonary blood flow changes within clinically acceptable margins of error. The prediction is made possible with normalization to a V̇/Q̇ of 1 for ECMO. This approach depends on measurements readily available and may allow immediate assessment of the cardiac output response.
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Affiliation(s)
- Kaspar F Bachmann
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Matthias Haenggi
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Stephan M Jakob
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Jukka Takala
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Luciano Gattinoni
- Department of Anesthesiology, Emergency and Intensive Care Medicine, University of Göttingen, Göttingen, Germany
| | - David Berger
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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