uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Abdominal lymph flow in an endotoxin sepsis model: Influence of spontaneous breathing and mechanical ventilation
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
2006 (English)In: Critical Care Medicine, ISSN 0090-3493, E-ISSN 1530-0293, Vol. 34, no 11, 2792-2798 p.Article in journal (Refereed) Published
Abstract [en]

OBJECTIVE: Lymph flow from the abdomen was investigated in a sepsis model. We also compared the effect on thoracic duct lymph flow of mechanical ventilation with different levels of positive end-expiratory pressure (PEEP) and spontaneous breathing with continuous positive airway pressure (CPAP). DESIGN: Experimental study. SETTING: Research laboratory in a university hospital. SUBJECTS: Thirty-two pigs. INTERVENTIONS: Animals were anesthetized. In study 1 (n = 18), an ultrasonic flow probe was put around the intact thoracic duct just caudal to the diaphragm, and animals were randomized to receive mechanical ventilation with a PEEP of 5 cm H2O or 15 cm H2O or breathed spontaneously in CPAP with a PEEP of 5 cm H2O. In study 2 (n = 6), the thoracic duct was cannulated and the cannula externalized through the abdominal wall for lymph collection; animals were then ventilated as in study 1. In all animals, endotoxin was infused at 15 μg/kg/hr for 2.5 hrs and then continued at 5 μg/kg/hr. In study 3, healthy (n = 4) and endotoxin-exposed (n = 4) pigs had intra-abdominal pressure increased to 27 cm H2O for 2 hrs by pneumoperitoneum. Lymph flow was measured as in study 1. MEASUREMENTS AND MAIN RESULTS: Lymph flow (mean ± se) was 2.5 ± 0.4 mL/min at baseline and increased to 3.9 ± 0.8 mL/min after 90 mins and 6.3 ± 1.6 mL/min after 150 mins (p < .005) of endotoxin exposure. PEEP 15 cm H2O decreased lymph flow in pigs with intact thoracic duct (flow probe recording) and in pigs with cannulated lymph duct when drained against the central venous pressure. However, when drained against atmospheric pressure, PEEP increased flow. Spontaneous breathing increased flow both in intact and in cannulated animals. CONCLUSIONS: Endotoxin increases lymph flow from the abdomen. Mechanical ventilation with high PEEP impedes lymph drainage and could increase lymph production. Spontaneous breathing increases flow and improves drainage of abdominal edema.

Place, publisher, year, edition, pages
2006. Vol. 34, no 11, 2792-2798 p.
Keyword [en]
sepsis, lymph, abdomen, positive end-expiratory pressure, mechanical ventilation
National Category
Medical and Health Sciences
URN: urn:nbn:se:uu:diva-19586DOI: 10.1097/01.CCM.0000242158.28619.09ISI: 000241639900012PubMedID: 16971857OAI: oai:DiVA.org:uu-19586DiVA: diva2:47358
Available from: 2006-11-30 Created: 2006-11-30 Last updated: 2014-01-23Bibliographically approved
In thesis
1. Effect of Ventilatory Support on Abdominal Fluid Balance in a Sepsis Model
Open this publication in new window or tab >>Effect of Ventilatory Support on Abdominal Fluid Balance in a Sepsis Model
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In patients affected by acute respiratory failure or acute respiratory distress syndrome (ARDS) the leading cause of death is failure of different vital organs other than the lungs, so called multiple organ dysfunction syndrome (MODS). The abdominal organs have a crucial role in the pathogenesis of this syndrome.

There is a lack of knowledge regarding the mechanisms by which mechanical ventilation can affect the abdominal compartment. One hypothesis is that mechanical ventilation can interfere with abdominal fluid balance causing edema and inflammation.

We addressed the question whether different levels of ventilatory support (mechanical ventilation with different levels of positive end-expiratory pressure, PEEP, and spontaneous breathing with or without PEEP) can influence abdominal edema and inflammation in both healthy and endotoxin-exposed animals.

The effect on lymphatic drainage from the abdomen exerted by different degrees of ventilatory support was evaluated (paper I). We demonstrated that endotoxin increases abdominal lymph production, that PEEP and mechanical ventilation increase lymph production but also impede lymphatic drainage; spontaneous breathing improves lymphatic drainage from the abdomen.

By adapting a non-invasive nuclear medicine imaging technique and validating it (paper II), we have been able to evaluate extravascular fluid accumulation (edema formation) in the abdomen over time (paper III) demonstrating that edema increases during endotoxemia, mimicking a sepsis-like condition, and that spontaneous breathing, compared to mechanical ventilation, reduces extravascular fluid. Pro-inflammatory cytokines TNF-α and IL-6 in intestinal biopsies are reduced during spontaneous breathing compared to mechanical ventilation.

Abdominal edema results in increased intra-abdominal pressure (IAP): in paper IV we analyzed the effect of increased intra-abdominal pressure on the respiratory system. Pulmonary shunt fraction increased with high IAP both in healthy and LPS animals, resulting in decreased level of oxygenation. These changes are only partially reversible by reducing IAP.

In conclusion, mechanical ventilation is a life-saving tool but the possible side effect at the extra-pulmonary level should be considered, and the introduction of some degree of spontaneous breathing when clinically possible is a suggested choice.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2013. 35 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 941
mechanical ventilation, lymph flow, spontaneous breathing, positive end-expiratory pressure, PEEP, abdominal edema, inflammation, intra-abdominal pressure, IAP
National Category
Anesthesiology and Intensive Care Physiology
Research subject
Anaesthesiology and Intensive Care; Clinical Physiology
urn:nbn:se:uu:diva-207218 (URN)978-91-554-8787-4 (ISBN)
Public defence
2013-12-09, Enghoffsalen, Entrance 50, University Hospital, Uppsala, 13:15 (English)
Swedish Heart Lung FoundationSwedish Research Council, 5315
Available from: 2013-11-15 Created: 2013-09-10 Last updated: 2014-01-23

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Lattuada, MarcoHedenstierna, Göran
By organisation
Clinical Physiology
In the same journal
Critical Care Medicine
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 174 hits
ReferencesLink to record
Permanent link

Direct link