Burn Injury and Pulmonary Sepsis: Development of a Clinically Relevant Model

Kimberly A. Davis, John M. Santaniello, Li Ke He, Kuzhali Muthu, Soman Sen, Stephen B. Jones, Richard L. Gamelli, Ravi Shankar

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Background: Despite improvements in the early resuscitation of the critically injured, mortality from multiple organ failure has remained stable, with the lung often the first organ to fail. Early intubation and mechanical ventilation predispose patients to the development of pneumonia and respiratory failure. Our objective was to establish a murine model of combined injury, consisting of burn/trauma and pulmonary sepsis with reproducible end-organ responses and mortality. Methods: Male B6D2F1 mice were divided into four groups: burn/infection (BI), burn (B), infection (I), and sham (S). Burned animals had a full-thickness 15% dorsal scald burn. BI and I groups were inoculated intratracheally with Pseudomonas aeruginosa (3-5 × 10 3 colony-forming units). S and B animals received saline intratracheally. All animals were resuscitated with 2 mL of intraperitoneal saline. Mortality was recorded at 24, 48, and 72 hours. Bacterial sepsis was confirmed by tissue Gram's stain of the lungs and positive organ and blood cultures for Pseudomonas aeruginosa. Femoral bone marrow cells were collected at 72 hours from surviving animals. Clonogenic potential was assessed by response to macrophage (M) colony-stimulating factor (CSF) and granulocyte-macrophage (GM) CSF in a soft agar assay and the data were represented as colonies per femur. Isolated alveolar macrophages and whole lung tissue were assayed for levels of the inflammatory cytokines tumor necrosis factor-α and interleukin-6. Results: Mortality at 72 hours was 30% in BI, 12% in I, and <10% in B and S groups. Pneumonia was documented in all infected animals at 24 hours by Gram's stain and positive tissue cultures for Pseudomonas aeruginosa. Systemic sepsis as confirmed by blood, and remote organ cultures was seen in BI animals only. Significantly increased responsiveness to M-CSF stimulations was noted in all groups (BI, 8,291 ± 1,4102 colonies/femur; B, 6,357 ± 806 colonies/femur; and I, 8,054 ± 1,112 colonies/femur; p < 0.05) relative to sham (3,369 ± 883 colonies/femur, p < 0.05). Maximal responsiveness to GM-CSF stimulation was noted in the BI group (11,932 ± 982 colonies/femur, p < 0.05), and similar GM responsiveness was noted in all other groups (B, 7,135 ± 548 colonies/femur; I, 7,023 ± 810 colonies/femur; and S, 6,829 ± 1,439 colonies/femur). Alveolar macrophage release of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 increased in all animals, but the magnitude of increase was not proportional to the strength of the inciting stimulus. Conclusion: Although minimal perturbations were seen after burn or pulmonary infection alone, the combined insult of burn and pulmonary sepsis resulted in statistically significant hematopoietic changes with increased monocytopoiesis. Only the combined injury resulted in systemic sepsis and significantly increased mortality. We have developed a clinically relevant model of trauma and pulmonary sepsis that will allow further clarification of the inflammatory response after injury and infection.

Original languageEnglish (US)
Pages (from-to)272-278
Number of pages7
JournalJournal of Trauma - Injury, Infection and Critical Care
Volume56
Issue number2
StatePublished - 2004
Externally publishedYes

Fingerprint

Lung Injury
Femur
Sepsis
Burns
Infection
Lung
Mortality
Pseudomonas aeruginosa
Wounds and Injuries
Organ Culture Techniques
Alveolar Macrophages
Granulocyte-Macrophage Colony-Stimulating Factor
Interleukin-6
Pneumonia
Tumor Necrosis Factor-alpha
Cytokines
Colony-Stimulating Factors
Macrophage Colony-Stimulating Factor
Multiple Organ Failure
Thigh

Keywords

  • Alveolar macrophage
  • Bronchoalveolar lavage (BAL)
  • Burn
  • Cytokine
  • Pneumonia
  • Sepsis
  • Thermal injury

ASJC Scopus subject areas

  • Surgery

Cite this

Davis, K. A., Santaniello, J. M., He, L. K., Muthu, K., Sen, S., Jones, S. B., ... Shankar, R. (2004). Burn Injury and Pulmonary Sepsis: Development of a Clinically Relevant Model. Journal of Trauma - Injury, Infection and Critical Care, 56(2), 272-278.

Burn Injury and Pulmonary Sepsis : Development of a Clinically Relevant Model. / Davis, Kimberly A.; Santaniello, John M.; He, Li Ke; Muthu, Kuzhali; Sen, Soman; Jones, Stephen B.; Gamelli, Richard L.; Shankar, Ravi.

In: Journal of Trauma - Injury, Infection and Critical Care, Vol. 56, No. 2, 2004, p. 272-278.

Research output: Contribution to journalArticle

Davis, KA, Santaniello, JM, He, LK, Muthu, K, Sen, S, Jones, SB, Gamelli, RL & Shankar, R 2004, 'Burn Injury and Pulmonary Sepsis: Development of a Clinically Relevant Model', Journal of Trauma - Injury, Infection and Critical Care, vol. 56, no. 2, pp. 272-278.
Davis, Kimberly A. ; Santaniello, John M. ; He, Li Ke ; Muthu, Kuzhali ; Sen, Soman ; Jones, Stephen B. ; Gamelli, Richard L. ; Shankar, Ravi. / Burn Injury and Pulmonary Sepsis : Development of a Clinically Relevant Model. In: Journal of Trauma - Injury, Infection and Critical Care. 2004 ; Vol. 56, No. 2. pp. 272-278.
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abstract = "Background: Despite improvements in the early resuscitation of the critically injured, mortality from multiple organ failure has remained stable, with the lung often the first organ to fail. Early intubation and mechanical ventilation predispose patients to the development of pneumonia and respiratory failure. Our objective was to establish a murine model of combined injury, consisting of burn/trauma and pulmonary sepsis with reproducible end-organ responses and mortality. Methods: Male B6D2F1 mice were divided into four groups: burn/infection (BI), burn (B), infection (I), and sham (S). Burned animals had a full-thickness 15{\%} dorsal scald burn. BI and I groups were inoculated intratracheally with Pseudomonas aeruginosa (3-5 × 10 3 colony-forming units). S and B animals received saline intratracheally. All animals were resuscitated with 2 mL of intraperitoneal saline. Mortality was recorded at 24, 48, and 72 hours. Bacterial sepsis was confirmed by tissue Gram's stain of the lungs and positive organ and blood cultures for Pseudomonas aeruginosa. Femoral bone marrow cells were collected at 72 hours from surviving animals. Clonogenic potential was assessed by response to macrophage (M) colony-stimulating factor (CSF) and granulocyte-macrophage (GM) CSF in a soft agar assay and the data were represented as colonies per femur. Isolated alveolar macrophages and whole lung tissue were assayed for levels of the inflammatory cytokines tumor necrosis factor-α and interleukin-6. Results: Mortality at 72 hours was 30{\%} in BI, 12{\%} in I, and <10{\%} in B and S groups. Pneumonia was documented in all infected animals at 24 hours by Gram's stain and positive tissue cultures for Pseudomonas aeruginosa. Systemic sepsis as confirmed by blood, and remote organ cultures was seen in BI animals only. Significantly increased responsiveness to M-CSF stimulations was noted in all groups (BI, 8,291 ± 1,4102 colonies/femur; B, 6,357 ± 806 colonies/femur; and I, 8,054 ± 1,112 colonies/femur; p < 0.05) relative to sham (3,369 ± 883 colonies/femur, p < 0.05). Maximal responsiveness to GM-CSF stimulation was noted in the BI group (11,932 ± 982 colonies/femur, p < 0.05), and similar GM responsiveness was noted in all other groups (B, 7,135 ± 548 colonies/femur; I, 7,023 ± 810 colonies/femur; and S, 6,829 ± 1,439 colonies/femur). Alveolar macrophage release of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 increased in all animals, but the magnitude of increase was not proportional to the strength of the inciting stimulus. Conclusion: Although minimal perturbations were seen after burn or pulmonary infection alone, the combined insult of burn and pulmonary sepsis resulted in statistically significant hematopoietic changes with increased monocytopoiesis. Only the combined injury resulted in systemic sepsis and significantly increased mortality. We have developed a clinically relevant model of trauma and pulmonary sepsis that will allow further clarification of the inflammatory response after injury and infection.",
keywords = "Alveolar macrophage, Bronchoalveolar lavage (BAL), Burn, Cytokine, Pneumonia, Sepsis, Thermal injury",
author = "Davis, {Kimberly A.} and Santaniello, {John M.} and He, {Li Ke} and Kuzhali Muthu and Soman Sen and Jones, {Stephen B.} and Gamelli, {Richard L.} and Ravi Shankar",
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TY - JOUR

T1 - Burn Injury and Pulmonary Sepsis

T2 - Development of a Clinically Relevant Model

AU - Davis, Kimberly A.

AU - Santaniello, John M.

AU - He, Li Ke

AU - Muthu, Kuzhali

AU - Sen, Soman

AU - Jones, Stephen B.

AU - Gamelli, Richard L.

AU - Shankar, Ravi

PY - 2004

Y1 - 2004

N2 - Background: Despite improvements in the early resuscitation of the critically injured, mortality from multiple organ failure has remained stable, with the lung often the first organ to fail. Early intubation and mechanical ventilation predispose patients to the development of pneumonia and respiratory failure. Our objective was to establish a murine model of combined injury, consisting of burn/trauma and pulmonary sepsis with reproducible end-organ responses and mortality. Methods: Male B6D2F1 mice were divided into four groups: burn/infection (BI), burn (B), infection (I), and sham (S). Burned animals had a full-thickness 15% dorsal scald burn. BI and I groups were inoculated intratracheally with Pseudomonas aeruginosa (3-5 × 10 3 colony-forming units). S and B animals received saline intratracheally. All animals were resuscitated with 2 mL of intraperitoneal saline. Mortality was recorded at 24, 48, and 72 hours. Bacterial sepsis was confirmed by tissue Gram's stain of the lungs and positive organ and blood cultures for Pseudomonas aeruginosa. Femoral bone marrow cells were collected at 72 hours from surviving animals. Clonogenic potential was assessed by response to macrophage (M) colony-stimulating factor (CSF) and granulocyte-macrophage (GM) CSF in a soft agar assay and the data were represented as colonies per femur. Isolated alveolar macrophages and whole lung tissue were assayed for levels of the inflammatory cytokines tumor necrosis factor-α and interleukin-6. Results: Mortality at 72 hours was 30% in BI, 12% in I, and <10% in B and S groups. Pneumonia was documented in all infected animals at 24 hours by Gram's stain and positive tissue cultures for Pseudomonas aeruginosa. Systemic sepsis as confirmed by blood, and remote organ cultures was seen in BI animals only. Significantly increased responsiveness to M-CSF stimulations was noted in all groups (BI, 8,291 ± 1,4102 colonies/femur; B, 6,357 ± 806 colonies/femur; and I, 8,054 ± 1,112 colonies/femur; p < 0.05) relative to sham (3,369 ± 883 colonies/femur, p < 0.05). Maximal responsiveness to GM-CSF stimulation was noted in the BI group (11,932 ± 982 colonies/femur, p < 0.05), and similar GM responsiveness was noted in all other groups (B, 7,135 ± 548 colonies/femur; I, 7,023 ± 810 colonies/femur; and S, 6,829 ± 1,439 colonies/femur). Alveolar macrophage release of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 increased in all animals, but the magnitude of increase was not proportional to the strength of the inciting stimulus. Conclusion: Although minimal perturbations were seen after burn or pulmonary infection alone, the combined insult of burn and pulmonary sepsis resulted in statistically significant hematopoietic changes with increased monocytopoiesis. Only the combined injury resulted in systemic sepsis and significantly increased mortality. We have developed a clinically relevant model of trauma and pulmonary sepsis that will allow further clarification of the inflammatory response after injury and infection.

AB - Background: Despite improvements in the early resuscitation of the critically injured, mortality from multiple organ failure has remained stable, with the lung often the first organ to fail. Early intubation and mechanical ventilation predispose patients to the development of pneumonia and respiratory failure. Our objective was to establish a murine model of combined injury, consisting of burn/trauma and pulmonary sepsis with reproducible end-organ responses and mortality. Methods: Male B6D2F1 mice were divided into four groups: burn/infection (BI), burn (B), infection (I), and sham (S). Burned animals had a full-thickness 15% dorsal scald burn. BI and I groups were inoculated intratracheally with Pseudomonas aeruginosa (3-5 × 10 3 colony-forming units). S and B animals received saline intratracheally. All animals were resuscitated with 2 mL of intraperitoneal saline. Mortality was recorded at 24, 48, and 72 hours. Bacterial sepsis was confirmed by tissue Gram's stain of the lungs and positive organ and blood cultures for Pseudomonas aeruginosa. Femoral bone marrow cells were collected at 72 hours from surviving animals. Clonogenic potential was assessed by response to macrophage (M) colony-stimulating factor (CSF) and granulocyte-macrophage (GM) CSF in a soft agar assay and the data were represented as colonies per femur. Isolated alveolar macrophages and whole lung tissue were assayed for levels of the inflammatory cytokines tumor necrosis factor-α and interleukin-6. Results: Mortality at 72 hours was 30% in BI, 12% in I, and <10% in B and S groups. Pneumonia was documented in all infected animals at 24 hours by Gram's stain and positive tissue cultures for Pseudomonas aeruginosa. Systemic sepsis as confirmed by blood, and remote organ cultures was seen in BI animals only. Significantly increased responsiveness to M-CSF stimulations was noted in all groups (BI, 8,291 ± 1,4102 colonies/femur; B, 6,357 ± 806 colonies/femur; and I, 8,054 ± 1,112 colonies/femur; p < 0.05) relative to sham (3,369 ± 883 colonies/femur, p < 0.05). Maximal responsiveness to GM-CSF stimulation was noted in the BI group (11,932 ± 982 colonies/femur, p < 0.05), and similar GM responsiveness was noted in all other groups (B, 7,135 ± 548 colonies/femur; I, 7,023 ± 810 colonies/femur; and S, 6,829 ± 1,439 colonies/femur). Alveolar macrophage release of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 increased in all animals, but the magnitude of increase was not proportional to the strength of the inciting stimulus. Conclusion: Although minimal perturbations were seen after burn or pulmonary infection alone, the combined insult of burn and pulmonary sepsis resulted in statistically significant hematopoietic changes with increased monocytopoiesis. Only the combined injury resulted in systemic sepsis and significantly increased mortality. We have developed a clinically relevant model of trauma and pulmonary sepsis that will allow further clarification of the inflammatory response after injury and infection.

KW - Alveolar macrophage

KW - Bronchoalveolar lavage (BAL)

KW - Burn

KW - Cytokine

KW - Pneumonia

KW - Sepsis

KW - Thermal injury

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