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Steiger C, Phan NV, Huang H, Sun H, Chu JN, Reker D, Gwynne D, Collins J, Tamang S, McManus R, Lopes A, Hayward A, Baron RM, Kim EY, Traverso G. Dynamic Monitoring of Systemic Biomarkers with Gastric Sensors. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102861. [PMID: 34713599 PMCID: PMC8693042 DOI: 10.1002/advs.202102861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Continuous monitoring in the intensive care setting has transformed the capacity to rapidly respond with interventions for patients in extremis. Noninvasive monitoring has generally been limited to transdermal or intravascular systems coupled to transducers including oxygen saturation or pressure. Here it is hypothesized that gastric fluid (GF) and gases, accessible through nasogastric (NG) tubes, commonly found in intensive care settings, can provide continuous access to a broad range of biomarkers. A broad characterization of biomarkers in swine GF coupled to time-matched serum is conducted . The relationship and kinetics of GF-derived analyte level dynamics is established by correlating these to serum levels in an acute renal failure and an inducible stress model performed in swine. The ability to monitor ketone levels and an inhaled anaesthetic agent (isoflurane) in vivo is demonstrated with novel NG-compatible sensor systems in swine. Gastric access remains a main stay in the care of the critically ill patient, and here the potential is established to harness this establishes route for analyte evaluation for clinical management.
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Affiliation(s)
- Christoph Steiger
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyBrigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
| | - Nhi V. Phan
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Hen‐Wei Huang
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyBrigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
| | - Haoying Sun
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Jacqueline N. Chu
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyMassachusetts General HospitalHarvard Medical SchoolBostonMA02115USA
| | - Daniel Reker
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyBrigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
| | - Declan Gwynne
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyBrigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
| | - Joy Collins
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Siddartha Tamang
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Rebecca McManus
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Aaron Lopes
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Alison Hayward
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of Comparative MedicineMassachusetts Institute of TechnologyCambridgeMA02139USA
| | - Rebecca M. Baron
- Division of Pulmonary and Critical Care MedicineDepartment of MedicineBrigham and Women's Hospital, Harvard Medical SchoolBostonMA02115USA
| | - Edy Y. Kim
- Division of Pulmonary and Critical Care MedicineDepartment of MedicineBrigham and Women's Hospital, Harvard Medical SchoolBostonMA02115USA
| | - Giovanni Traverso
- Koch Institute for Integrative Cancer ResearchMassachusetts Institute of TechnologyCambridgeMA02139USA
- Division of GastroenterologyBrigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
- Department of Mechanical EngineeringMassachusetts Institute of TechnologyCambridgeMA02139USA
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Tan B, Wong JJM, Sultana R, Koh JCJW, Jit M, Mok YH, Lee JH. Global Case-Fatality Rates in Pediatric Severe Sepsis and Septic Shock: A Systematic Review and Meta-analysis. JAMA Pediatr 2019; 173:352-362. [PMID: 30742207 PMCID: PMC6450287 DOI: 10.1001/jamapediatrics.2018.4839] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
IMPORTANCE The global patterns and distribution of case-fatality rates (CFRs) in pediatric severe sepsis and septic shock remain poorly described. OBJECTIVE We performed a systematic review and meta-analysis of studies of children with severe sepsis and septic shock to elucidate the patterns of CFRs in developing and developed countries over time. We also described factors associated with CFRs. DATA SOURCES We searched PubMed, Web of Science, Excerpta Medica database, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Cochrane Central systematically for randomized clinical trials and prospective observational studies from earliest publication until January 2017, using the keywords "pediatric," "sepsis," "septic shock," and "mortality." STUDY SELECTION Studies involving children with severe sepsis and septic shock that reported CFRs were included. Retrospective studies and studies including only neonates were excluded. DATA EXTRACTION AND SYNTHESIS We conducted our systematic review and meta-analysis in close accordance to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pooled case-fatality estimates were obtained using random-effects meta-analysis. The associations of study period, study design, sepsis severity, age, and continents in which studies occurred were assessed with meta-regression. MAIN OUTCOMES AND MEASURES Meta-analyses to provide pooled estimates of CFR of pediatric severe sepsis and septic shock over time. RESULTS Ninety-four studies that included 7561 patients were included. Pooled CFRs were higher in developing countries (31.7% [95% CI, 27.3%-36.4%]) than in developed countries (19.3% [95% CI, 16.4%-22.7%]; P < .001). Meta-analysis of CFRs also showed significant heterogeneity across studies. Continents that include mainly developing countries reported higher CFRs (adjusted odds ratios: Africa, 7.89 [95% CI, 6.02-10.32]; P < .001; Asia, 3.81 [95% CI, 3.60-4.03]; P < .001; South America, 2.91 [95% CI, 2.71-3.12]; P < .001) than North America. Septic shock was associated with higher CFRs than severe sepsis (adjusted odds ratios, 1.47 [95% CI, 1.41-1.54]). Younger age was also a risk factor (adjusted odds ratio, 0.95 [95% CI, 0.94-0.96] per year of increase in age). Earlier study eras were associated with higher CFRs (adjusted odds ratios for 1991-2000, 1.24 [95% CI, 1.13-1.37]; P < .001) compared with 2011 to 2016. Time-trend analysis showed higher CFRs over time in developing countries than developed countries. CONCLUSIONS AND RELEVANCE Despite the declining trend of pediatric severe sepsis and septic shock CFRs, the disparity between developing and developed countries persists. Further characterizations of vulnerable populations and collaborations between developed and developing countries are warranted to reduce the burden of pediatric sepsis globally.
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Affiliation(s)
| | - Judith Ju-Ming Wong
- Children’s Intensive Care Unit, KK Women’s
and Children’s Hospital, Singapore
| | | | | | - Mark Jit
- London School of Hygiene and Tropical Medicine,
London, United Kingdom
| | - Yee Hui Mok
- Children’s Intensive Care Unit, KK Women’s
and Children’s Hospital, Singapore
| | - Jan Hau Lee
- Duke-NUS Medical School, Singapore,Children’s Intensive Care Unit, KK Women’s
and Children’s Hospital, Singapore
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Moore JE. Newer monitoring techniques to determine the risk of necrotizing enterocolitis. Clin Perinatol 2013; 40:125-34. [PMID: 23415268 DOI: 10.1016/j.clp.2012.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Necrotizing enterocolitis affects up to 10% of neonates who are born weighing less than 1500 g. It has a high rate of morbidity and mortality, and predicting infants who will be affected has so far been unsuccessful. In this article, a number of new methods are discussed from the literature to determine if any currently available techniques may allow for the identification of patients who are at increased risk for developing this potentially lethal disease.
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Affiliation(s)
- James E Moore
- Department of Pediatrics, University of Texas, Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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Holley A, Lukin W, Paratz J, Hawkins T, Boots R, Lipman J. Review article: Part two: Goal-directed resuscitation--which goals? Perfusion targets. Emerg Med Australas 2012; 24:127-35. [PMID: 22487661 DOI: 10.1111/j.1742-6723.2011.01515.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Haemodynamic targets, such as cardiac output, mean arterial blood pressure and central venous oxygen saturations, remain crude predictors of tissue perfusion and oxygen supply at a cellular level. Shocked patients may appear adequately resuscitated based on normalization of global vital signs, yet they are still experiencing occult hypoperfusion. If targeted resuscitation is employed, appropriate use of end-points is critical. In this review, we consider the value of directing resuscitation at the microcirculation or cellular level. Current technologies available include sublingual capnometry, video microscopy of the microcirculation and near-infrared spectroscopy providing a measure of tissue oxygenation, whereas base deficit and lactate potentially provide a surrogate measure of the adequacy of global perfusion. The methodology and evidence for these technologies guiding resuscitation are considered in this narrative review.
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Affiliation(s)
- Anthony Holley
- Departments of Intensive Care Medicine Emergency Medicine, Royal Brisbane and Women's Hospital, Butterfield Street, Herston, QLD 4029, Australia.
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Jat KR, Jhamb U, Gupta VK. Serum lactate levels as the predictor of outcome in pediatric septic shock. Indian J Crit Care Med 2011; 15:102-7. [PMID: 21814374 PMCID: PMC3145293 DOI: 10.4103/0972-5229.83017] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background and Aims: An association of high lactate levels with mortality has been found in adult patients with septic shock. However, there is controversial literature regarding the same in children. The aim of this study was to find the correlation of serum lactate levels in pediatric septic shock with survival. Settings and Design: This was a prospective observational study at PICU of a tertiary care center of North India. Materials and Methods: A total of 30 children admitted to PICU with diagnosis of septic shock were included in the study. PRISM III score and demographic characteristics of all children were recorded. Serum lactate levels were measured in arterial blood at 0-3, 12, and 24 h of PICU admission. The outcome (survival or death) was correlated with serum lactate levels. Results: Septic shock was the most common (79.3%) type of shock and had 50% mortality. Initial as well as subsequent lactate levels were significantly higher in nonsurvivors. A lactate value of more than 45 mg/dl (5 mmol/l) at 0–3, 12, and 24 h of PICU admission had an odds ratio for death of 6.7, 12.5, and 8.6 (95% CI: 1.044–42.431, 1.850–84.442, 1.241–61.683) with a positive predictive value (PPV) of 38%, 71%, 64% and a negative predictive value (NPV) of 80%, 83%, and 83%, respectively. Conclusions: Nonsurvivors had higher blood lactate levels at admission as well as at 12 and 24 h. A lactate value of more than 45 mg/dl (5 mmol/l) was a good predictor of death.
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Affiliation(s)
- Kana Ram Jat
- Department of Pediatrics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
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6
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Hickey M, Samuels N, Randive N, Langford RM, Kyriacou PA. Investigation of photoplethysmographic signals and blood oxygen saturation values obtained from human splanchnic organs using a fiber optic sensor. J Clin Monit Comput 2011; 25:245-55. [PMID: 21953382 DOI: 10.1007/s10877-011-9302-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 09/08/2011] [Indexed: 11/27/2022]
Abstract
OBJECTIVE A reliable, continuous method of monitoring splanchnic organ oxygen saturation could allow for the early detection of malperfusion, and may prevent the onset of multiple organ failure. Current monitoring techniques have not been widely accepted in critical care monitoring. As a preliminary to developing a continuous indwelling device, this study evaluates a new handheld fiber optic photoplethysmographic (PPG) sensor for estimating the blood oxygen saturation (SpO(2)) of splanchnic organs during surgery. METHODS A fiber optic splanchnic PPG sensor, instrumentation system and virtual instrument were developed to facilitate PPG and SpO(2) measurement from splanchnic organs. Following Local Research Ethics Committee approval, the sensor was evaluated on seventeen ASA 1 and 2 patients undergoing open laparotomy. PPG signals were obtained from the large bowel, small bowel, liver and stomach. Simultaneous PPG signals from the finger were also obtained using an identical fiber optic sensor. RESULTS Good quality PPG signals with high signal-to-noise (SNR) ratios were obtained from all splanchnic sites under investigation. Analysis of the ac and dc amplitudes of the red and infrared PPG signals showed there to be a statistically significant difference between PPG signals obtained from splanchnic organs with those obtained from the finger (using fiber optic sensors). Estimated SpO(2) values from the splanchnic organs show good agreement with those obtained from the finger using both a fiber optic sensor and a commercial device. Furthermore, the results of a Bland and Altman analysis indicate that fiber optic splanchnic pulse oximetry, particularly of the bowel, may provide a suitable method for monitoring splanchnic organ perfusion. CONCLUSION The evaluation of a new fiber optic sensor on anaesthetized patients undergoing laparotomy demonstrated that good quality PPG signals and SpO(2) estimates can be obtained from splanchnic organs. Such a sensor may provide a useful tool for the intraoperative assessment of splanchnic perfusion.
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Affiliation(s)
- Michelle Hickey
- School of Engineering and Mathematical Sciences, City University London, Northampton Square, London, EC1V 0HB, UK.
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Upadhyay KK, Singh VP, Murthy T. Gastric Tonometry as a Prognostic Index of Mortality in Sepsis. Med J Armed Forces India 2011; 63:337-40. [PMID: 27408044 DOI: 10.1016/s0377-1237(07)80010-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Accepted: 06/20/2007] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Splanchnic hypoperfusion in sepsis leads to translocation of bacteria from gut and development of multi-organ dysfunction syndrome (MODS), with increased mortality in critically ill patients. Gastric tonometry can detect this hypoperfusion by measuring carbon dioxide tension (PgCO2) and intramucosal pH (pHi) from gastric mucosa. Therapeutic intervention aimed at improving gut perfusion can improve the outcome and prognosticate the mortality in sepsis patients. METHODS 100 patients with clinical diagnosis of sepsis were included and divided into two groups of 50 each. Group A patients were managed traditionally without gastric tonometry and in Group B gastric tonometry was used for therapeutic intervention. The intramucosal PCO2, pHi, end tidal carbon dioxide tension (EtCO2) and (PgCO2-EtCO2) differences were monitored at 0, 12 and 24 hours interval. RESULT Overall mortality in Group A was 64 % and 54 % in Group B. In Group B 45% patients developed MODS and 54 % died with low pHi. As an index of mortality low pHi had a sensitivity of 70% and specificity of 65%. CONCLUSION There is a good correlation between mortality prediction on the basis of pHi and PgCO2-EtCO2 difference and actual mortality in critically ill patients. The gastric tonometer should be used to predict mortality and guide resuscitation in septicemia.
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Affiliation(s)
- K K Upadhyay
- Associate Professor (Department of Anaesthesiology and Critical Care), Armed Forces Medical College, Pune-411040
| | - V P Singh
- ADMS, HQ Western Command, Army Hospital (R&R), Delhi Cantt
| | - Tvsp Murthy
- Senior Advisor (Neuroanaesthesia), Army Hospital (R&R), Delhi Cantt
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8
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Hickey M, Samuels N, Randive N, Langford RM, Kyriacou PA. An in vivo investigation of photoplethysmographic signals and preliminary pulse oximetry estimation from the bowel using a new fiberoptic sensor. Anesth Analg 2011; 112:1104-9. [PMID: 21346164 DOI: 10.1213/ane.0b013e31820f8df3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The continuous monitoring of splanchnic organ oxygen saturation could make the early detection of inadequate tissue oxygenation feasible, reducing the risk of hypoperfusion, severe ischemia, multiple organ failure, and, ultimately, death. Current methods for assessing splanchnic perfusion have not been widely accepted for use in the clinical care environment. In an attempt to overcome the limitations of the current techniques, a new fiberoptic photoplethysmographic (PPG)/pulse oximetry sensor was developed as a means of assessing splanchnic organ perfusion during surgery in humans. METHODS A new fiberoptic splanchnic pulse oximeter and an optically identical fiberoptic finger pulse oximeter have been developed. Simultaneous PPG signals and preliminary estimates of arterial oxygen saturation from the bowel (small and large) and finger were obtained in 17 patients (3 men and 14 women) undergoing open laparotomy. RESULTS Good quality PPG signals were obtained from the small and large bowel and from the finger in all patients (lower 95% confidence limit for the proportion was 0.64). Comparisons of blood oxygen saturation values acquired when using the splanchnic and the finger fiberoptic sensors and a commercial finger pulse oximeter indicated that there was no statistically significant difference between them (all P>0.454). A Bland and Altman plot of the difference between blood oxygen saturation values from the bowel fiberoptic pulse oximeter and the fiberoptic finger pulse oximeter against their mean showed that the limits of agreement between the 2 pulse oximeters were -3.8% and 4.2% for small bowel measurements, and -3.4% and 4.3% for large bowel measurements. The 95% prediction interval for the difference between the 2 devices was between -4.2% and 4.7%. CONCLUSION This study demonstrated that good quality PPG signals can be obtained from the bowel using a new fiberoptic sensor. Further evaluation is required to determine whether fiberoptic pulse oximetry of the bowel may provide a suitable method for monitoring splanchnic perfusion.
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Affiliation(s)
- Michelle Hickey
- School of Engineering and Mathematical Sciences, City University, London, EC1V 0HB, UK
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Hickey M, Samuels N, Randive N, Langford R, Kyriacou PA. Preliminary assessment of abdominal organ perfusion utilizing a fiber optic photoplethysmographic sensor. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2010; 2010:1020-3. [PMID: 21096995 DOI: 10.1109/iembs.2010.5627751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In an attempt to overcome the limitations of current techniques for monitoring abdominal organ perfusion, a prototype reflectance fiber optic photoplethysmographic (PPG) sensor and processing system was evaluated on seventeen anaesthetized patients undergoing laparotomy. Good quality PPG signals were obtained from the large bowel, small bowel, liver and stomach. Simultaneous PPG signals from the finger were also obtained for comparison purposes using an identical fiber optic sensor. Analysis of the mean ac and dc PPG amplitudes of all acquired signals indicated larger amplitudes for those signals obtained from abdominal organs than those obtained from the finger. Mean estimated blood oxygen saturation (SpO(2)) values from all abdominal sites showed good agreement with those obtained from the finger using both the finger fiber optic sensor and a commercial finger pulse oximeter. Furthermore, a Bland and Altman between-method-differences analysis on the estimated SpO(2) data suggests that a fiber optic abdominal sensor may be a suitable method for the evaluation of abdominal organ perfusion.
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Affiliation(s)
- M Hickey
- School of Engineering and Mathematical Sciences, City University, London, UK.
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Hickey M, Samuels N, Randive N, Langford RM, Kyriacou PA. Measurement of splanchnic photoplethysmographic signals using a new reflectance fiber optic sensor. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:027012. [PMID: 20459286 DOI: 10.1117/1.3374355] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Splanchnic organs are particularly vulnerable to hypoperfusion. Currently, there is no technique that allows for the continuous estimation of splanchnic blood oxygen saturation (SpO(2)). As a preliminary to developing a suitable splanchnic SpO(2) sensor, a new reflectance fiber optic photoplethysmographic (PPG) sensor and processing system are developed. An experimental procedure to examine the effect of fiber source detector separation distance on acquired PPG signals is carried out before finalizing the sensor design. PPG signals are acquired from four volunteers for separation distances of 1 to 8 mm. The separation range of 3 to 6 mm provides the best quality PPG signals with large amplitudes and the highest signal-to-noise ratios (SNRs). Preliminary calculation of SpO(2) shows that distances of 3 and 4 mm provide the most realistic values. Therefore, it is suggested that the separation distance in the design of a fiber optic reflectance pulse oximeter be in the range of 3 to 4 mm. Preliminary PPG signals from various splanchnic organs and the periphery are obtained from six anaesthetized patients. The normalized amplitudes of the splanchnic PPGs are, on average, approximately the same as those obtained simultaneously from the periphery. These observations suggest that fiber optic pulse oximetry may be a valid monitoring technique for splanchnic organs.
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Affiliation(s)
- Michelle Hickey
- City University London, School of Engineering and Mathematical Sciences, Northampton Square, London, EC1V 0HB United Kingdom.
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11
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Abstract
the continuous monitoring of splanchnic organ oxygen saturation (SpO2) would make the early detection of inadequate tissue oxygenation feasible, reducing the risk of hypoperfusion, severe ischemia, multiple organ failure, and, ultimately, death. In an attempt to create a splanchnic SpO2 sensor that can be used intra-operatively, pre-operatively and post-operatively this paper describes the design and technical evaluation of fiber optic based reflectance pulse oximeter sensor and processing system. In a detailed investigation to determine the optimal source-emitter spacing it was found that the optimum separation distance was between 3mm and 6mm. In vivo thermal testing showed that the rise in temperature at the tip of the fiber at both wavelengths was insignificant and therefore should have no effect in the splanchnic tissue.
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Affiliation(s)
- M Hickey
- School of Engineering and Mathematical Sciences, City University, London, UK.
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12
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Correlation of abdominal site near-infrared spectroscopy with gastric tonometry in infants following surgery for congenital heart disease. Pediatr Crit Care Med 2008; 9:62-8. [PMID: 18477915 DOI: 10.1097/01.pcc.0000298640.47574.da] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Splanchnic oximetry, as measured by near-infrared spectroscopy (NIRS), correlates with gastric tonometry as a means of assessing regional (splanchnic) oxygenation and perfusion. DESIGN Prospective, data-gathering study. SETTING Pediatric cardiac intensive care unit in a tertiary care children's hospital. SUBJECTS Neonates and infants with congenital heart disease who underwent catheter intervention or surgical repair requiring cardiopulmonary bypass. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Twenty neonates and infants were studied within 48 hrs of surgery. We measured somatic saturation (rSO2) via NIRS sensors placed over the anterior abdomen (splanchnic bed) and dorsal lateral flank (renal bed). Somatic rSO2 readings were paired with simultaneous points of intramucosal gastric pH (pHi), measured by tonometry. The rSO2 readings were paired with serum lactate and measurements of systemic mixed venous saturation (SVO2). There was strong correlation between the abdominal rSO2 and pHi (r = .79; p < .0001) as well as between abdominal rSO2 and SVO2 (r = .89; p < .0001). There was also significant negative correlation between the abdominal rSO2 and serum lactate (r = .77; p < .0001). Correlations between the dorsal lateral (renal) rSO2 measurements and serum lactate and SVO2 were also significant but not as strong. CONCLUSIONS Abdominal site rSO2, measured in infants with either single or biventricular physiology, exhibits a strong correlation with gastric pHi as well as with serum lactate and SVO2. The results indicate that rSO2 measurements over the anterior abdominal wall correlate more strongly than flank rSO2 with regard to systemic indices of oxygenation and perfusion. This study suggests that the NIRS monitor is a valid modality to obtain an easy, immediate, and noninvasive measurement of splanchnic rSO2 in infants following cardiac surgery for congenital heart disease.
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Messaris E, Kekis P, Memos N, Chatzigianni E, Menenakos E, Leandros E, Konstadoulakis MM. Sepsis: Prognostic Role of Apoptosis Regulators in Gastrointestinal Cells. World J Surg 2007; 31:787-94. [PMID: 17372670 DOI: 10.1007/s00268-005-0742-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Intestinal epithelial cell apoptosis has been reported in sepsis as a mechanism of organ failure. The aim of this study was to clarify the role of apoptosis-regulating proteins (bcl-2, bax, cytochrome-c, and caspase-8) in septic rats by studying their expression in gastric and intestinal epithelial cells. METHODS Adult Wistar rats were subjected to the cecal ligation and puncture (CLP) model of sepsis and randomly divided into two study groups. Sixty-two animals were sacrificed 6, 12, 24, 36, 48, and 60 h post-procedure, and 50 animals served as the survival study group. Sham-operated animals (n = 40) were used as controls. Gastric and intestinal tissue was excised, and immunohistochemical detection of bcl-2, bax, cytochrome-c, and caspase-8 protein expression was performed. RESULTS In gastric mucosa, sepsis induced upregulation of bax and downregulation of caspase-8 expression (p = 0.053 and p = 0.05, respectively). Both bax and caspase-8 were upregulated as early as 6 h post CLP and progressively decreased (p = 0.001, p = 0.004 respectively). In contrast, the expression of the anti-apoptotic bcl-2 was upregulated progressively during the sepsis syndrome (p = 0.03). In intestine, sepsis induced a fourfold upregulation of the cytoprotective bcl-2 (p = 0.0001), accompanied by a remarkable increase in bax (p = 0.002) and caspase-8 (p = 0.0001) expression and a decrease in cytochrome-c expression (p = 0.02). The time distribution of the apoptosis regulators followed the same pattern as in gastric tissue, showing an upregulation of the proapoptotic bax and cytochrome c (p = 0.04) during the early phases and a progressively increased expression of bcl-2 during the late phases (p = 0.0001). Bax expression in gastric epithelium of subjects with septic syndrome was detrimental to survival (p = 0.0001), whereas the expression of the cytoprotective bcl-2 in intestinal epithelium appeared to favor a good prognosis (p = 0.0001). CONCLUSIONS Sepsis results in alterations of apoptosis regulators in gastrointestinal cells. Alterations of bax and bcl-2 expression in gastric and intestinal epithelial cells may predict the outcome in septic rats.
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Affiliation(s)
- Evangelos Messaris
- Laboratory of Surgical Research, First Department of Propaedeutic Surgery, Athens Medical School, Hippokration Hospital, 11527 Vas, Sofias Ave 114, Athens, Greece
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Abstract
Microcirculatory dysfunctions play a central role in the pathophysiology of sepsis and shock. Modern methods enable microvascular monitoring in man and offer the possibility to test the effect of novel therapeutical strategies for sepsis. Furthermore, these techniques may be future tools for the monitoring of critically ill patients. In this review, we will describe four microvascular monitoring devices and give an overview of the microcirculatory changes observed during the course of sepsis. Laser Doppler fluxmetry is an easy to use noninvasive technique to measure tissue perfusion enabling monitoring of the effect of different catecholamines on the gastric perfusion during sepsis. Increased microvascular permeability and altered blood flow in septic patients can be quantified by venous congestion plethysmography. Alterations in sublingual microvascular blood flow are detected by intravital microscopy in septic patients and were identified as an outcome predictor. Furthermore, the role of gastrointestinal pCO2-tonometry for microcirculatory monitoring of the perfusion of splanchnic organs during sepsis is discussed. The true clinical value of these techniques has yet to be established and will depend on larger clinical trials showing an impact on diagnostics and patient management.
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Affiliation(s)
- A Bauer
- Klinik für Anaesthesiologie, Klinikum der Universität München-Grosshadern, Marchioninistrasse 15, 81377 München-Grosshadern
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Thorburn K, Durward A, Tibby SM, Murdoch IA. Effects of feeding on gastric tonometric measurements in critically ill children. Crit Care Med 2004; 32:246-9. [PMID: 14707587 DOI: 10.1097/01.ccm.0000104115.03922.ac] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the effect of gastric feeding on the measurement of gastric intramucosal PCO2 (PiCO2) and its derived gastric intramucosal PCO2-arterial PCO2 difference (PiCO2-PaCO2 difference) and gastric intramucosal pH (pHi) in a group of critically ill children using recirculating gas tonometry. DESIGN Prospective clinical pilot study. SETTING Sixteen bed pediatric intensive care unit. PATIENTS Ten mechanically ventilated and hemodynamically stable children (median age, 20.1 months [interquartile range (IQR), 9.7-47.6 months] and median weight, 10.2 kg [IQR, 10-16.5 kg]). INTERVENTIONS A 7-French recirculating gas tonometer was placed in the stomach via the orogastric route. MEASUREMENTS In each patient, baseline fasted/unfed PiCO2, PiCO2-PaCO2 difference, and pHi were determined hourly over a 5-hr period. Gastric feeding was then reestablished (3 mL/kg/hr) within a median time of 3 hrs and a further 5 hourly measurements were determined. Concurrent arterial blood gas and lactate measurements were taken. Blood pressure and heart rate was monitored throughout. MAIN RESULTS Hemodynamic parameters remained stable throughout the study period. When compared with the unfed/fasting state, PiCO2 measurements and PiCO2-PaCO2 difference were consistently lower and pHi values higher than when the patients were fed (two-way analysis of variance for repeated measures: all p <.001 between groups). Measurements did not vary over time. CONCLUSIONS In our patient group, gastric feeding decreased the PiCO2 and PiCO2-PaCO2 difference and increased pHi compared with the unfed state. These findings are in contrast to those found in adult studies.
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Affiliation(s)
- Kentigern Thorburn
- Department of Paediatric Intensive Care, Royal Liverpool Children's Hospital-Alder Hey, UK
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van Haren FMP, Rozendaal FW, van der Hoeven JG. The Effect of Vasopressin on Gastric Perfusion in Catecholamine-Dependent Patients in Septic Shock. Chest 2003; 124:2256-60. [PMID: 14665508 DOI: 10.1378/chest.124.6.2256] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
OBJECTIVE To study the effect of continuous infusion of vasopressin on the splanchnic circulation in patients with severe septic shock. DESIGN Prospective clinical study. SETTING ICU in a teaching hospital. PATIENTS Eleven consecutive patients with documented septic shock who remained hypotensive despite norepinephrine infusion at a rate > or =0.2 microg/kg/min. INTERVENTIONS Insertion of a gastric tonometry catheter, and continuous infusion of vasopressin 0.04 U/min during 4 h. MEASUREMENTS AND MAIN RESULTS Difference between gastric and arterial CO(2) partial pressure (P[g-a]CO(2) gap), mean arterial pressure, and cardiac index were recorded at baseline and after 15 min, 30 min, 60 min, 120 min, and 240 min. RESULTS The median P(g-a)CO(2) gap increased from 5 mm Hg at baseline to 19 mm Hg after 4 h (p = 0.022). Mean arterial pressure increased from 61 +/- 13 mm Hg at baseline to 68 +/- 9 mm Hg after 4 h (p = 0.055). No significant changes in cardiac index were noted. CONCLUSIONS In norepinephrine-dependent patients in septic shock, continuous infusion of low-dose vasopressin results in a significant increase of the P(g-a)CO(2) gap compatible with GI hypoperfusion.
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Affiliation(s)
- Frank M P van Haren
- Department of Intensive Care Medicine, Jeroen Bosch Hospital, PO Box 90153, 5200 ME 's-Hertogenbosch, the Netherlands.
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Carcillo JA, Fields AI. Clinical practice parameters for hemodynamic support of pediatric and neonatal patients in septic shock. Crit Care Med 2002; 30:1365-78. [PMID: 12072696 DOI: 10.1097/00003246-200206000-00040] [Citation(s) in RCA: 360] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The Institute of Medicine has called for the development of clinical guidelines and practice parameters to develop "best practice" and potentially improve patient outcome. OBJECTIVE To provide American College of Critical Care Medicine clinical guidelines for hemodynamic support of neonates and children with septic shock. SETTING Individual members of the Society of Critical Care Medicine with special interest in neonatal and pediatric septic shock were identified from literature review and general solicitation at Society of Critical Care Medicine Educational and Scientific Symposia (1998-2001). METHODS The MEDLINE literature database was searched with the following age-specific keywords: sepsis, septicemia, septic shock, endotoxemia, persistent pulmonary hypertension, nitric oxide, and extracorporeal membrane oxygenation. More than 30 experts graded literature and drafted specific recommendations by using a modified Delphi method. More than 30 more experts then reviewed the compiled recommendations. The task-force chairman modified the document until <10% of experts disagreed with the recommendations. RESULTS Only four randomized controlled trials in children with septic shock could be identified. None of these randomized trials led to a change in practice. Clinical practice has been based, for the most part, on physiologic experiments, case series, and cohort studies. Despite relatively low American College of Critical Care Medicine-graded evidence in the pediatric literature, outcomes in children have improved from 97% mortality in the 1960s to 60% in the 1980s and 9% mortality in 1999. U.S. hospital survival was three-fold better in children compared with adults (9% vs. 27% mortality) in 1999. Shock pathophysiology and response to therapies is age specific. For example, cardiac failure is a predominant cause of death in neonates and children, but vascular failure is a predominant cause of death in adults. Inotropes, vasodilators (children), inhaled nitric oxide (neonates), and extracorporeal membrane oxygenation can be more important contributors to survival in the pediatric populations, whereas vasopressors can be more important contributors to adult survival. CONCLUSION American College of Critical Care Medicine adult guidelines for hemodynamic support of septic shock have little application to the management of pediatric or neonatal septic shock. Studies are required to determine whether American College of Critical Care Medicine guidelines for hemodynamic support of pediatric and neonatal septic shock will be implemented and associated with improved outcome.
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Affiliation(s)
- Joseph A Carcillo
- Children's Hospital of Pittsburgh, Division of Critical Care Medicine, 15213, USA.
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Abstract
Maintenance of adequate perfusion is essential for health of the intestinal mucosa. Methods available to assess intestinal perfusion provide information on mesenteric blood flow, which may differ from mucosal flow. Intramucosal pH (pH(i)) is influenced by tissue oxygenation and perfusion. Gastric pH(i) can be measured using the technique of tonometry. A prospective observational clinical study was performed to examine relationships between measured gastric pH(i) and mucosal CO(2) (mCO(2)), and acid-base balance, gastrointestinal complications (necrotizing enterocolitis and perforation), and death in infants <1500 g birth weight. A nasogastric tonometry catheter (size 5F) was inserted into the stomach of infants, and pH(i) was calculated from mCO(2) levels measured using saline tonometry. Measurements were performed at 3, 12, 24, and 48 h, then daily until arterial access was unavailable. Two hundred eleven sets of measurements were performed on 38 infants [birth weight (mean +/-SD), 863 +/- 241 g; gestation, 26.5 +/- 1.8 wk; and median Clinical Risk Index for Babies score, 8.0 (interquartile range, 5.0-10.75)]. Mean pH(i) was 7.27 (95% confidence interval, 7.26-7.28) and mean mCO(2) was 47.0 mm Hg (95% confidence interval, 45.7-48.3 mm Hg). pH(i) and mCO(2) correlated significantly with arterial pH (pH(a)), arterial PCO(2) (PaCO(2)), and arterial base excess. There were no significant relationships between pH(a) and pH gap (pH(a)-pH(i)) or CO(2) gap (mCO(2)-PaCO(2)). Recurrent low pH(i) (<7.2 on more than one occasion) and an mCO(2)/PaCO(2) ratio of > or =1.29 were significantly associated with an increase in gastrointestinal complications. There were no statistically significant associations with death. In conclusion, changes in pH gap and CO(2) gap can occur without alteration in pH(a). Abnormalities in pH(i) might predict gastrointestinal complications in infants <1500 g.
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Affiliation(s)
- M E Campbell
- Academic Department of Child Health, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Neonatal Unit, Homerton Hospital, London, United Kingdom E9 6SR
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Abstract
Gastric tonometry has proved to be a sensitive but not specific predictor of outcome in the critically ill. The data accumulated to date indicate that those patients able to achieve or maintain a normal gastric mucosal pH do better than those who do not. In addition, therapy aimed at improving an abnormal gastric mucosal pH has proved to be less successful. These findings may simply indicate that tonometry identifies those "responders" and "nonresponders," as becomes increasingly apparent in populations of critical care patients receiving interventional therapy. Gastric tonometry has undergone a number of methodologic changes over the last decade, seeing a switch from saline to automated gas tonometry. Along with this switch of methodology has come a deeper scrutiny of the indices used to assess gut perfusion. Most studies (including all the interventional ones) have used gastric mucosal pH. The newer indices of gut luminal PCO2 (PgCO2) referenced to arterial CO2 (PgCO2-PaCO2) or end tidal CO2 (PgCO2-PeCO2), although relatively well validated, remain to be proven as predictors of outcome or guides to interventional therapy. If we take a fresh look at the interventional trials in intensive care patients, there is a very definite trend toward benefit in the protocol groups, although they are generally reported as negative studies. There is much to be accomplished, however, before we accept the gastric tonometer as a routine tool with which to guide therapy based on gastrointestinal perfusion, including a greater understanding of gastrointestinal physiology and, as ever, the call for an adequately powered prospective randomized controlled trial to evaluate the clinical utility of gas tonometry.
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Affiliation(s)
- M A Hamilton
- Center for Anesthesia, Middlesex Hospital, and Center for Anesthesia, University College, London, UK
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Hatherill M, Jones GD, Murdoch IA. Pediatric gastric tonometry: lessons from the adult experience. Crit Care Med 1999; 27:2604. [PMID: 10579307 DOI: 10.1097/00003246-199911000-00067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gastrointestinal PCO2 tonometry in 1998. Curr Opin Crit Care 1999. [DOI: 10.1097/00075198-199906000-00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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