Hemodynamic and metabolic features of a porcine systemic low flow state model

cc5793 CCJ Poster presentation Hemodynamic and metabolic features of a porcine systemic low flow state model Azevedo LCP Maciel AT Noritomi D Schettino GPP Park M

Intensive Care Laboratory, Research and Education Institute, Hospital Sírio-Libanês, São Paulo – SP, Brazil

Intensive Care Unit, Hospital das Clínicas, HCFMUSP, São Paulo – SP, Brazil

Critical Care Fourth International Symposium on Intensive Care and Emergency Medicine for Latin America Meeting abstracts http://ccforum.com/supplements/notes/ccv11s3-info.pdf Fourth International Symposium on Intensive Care and Emergency Medicine for Latin America São Paulo, Brazil

20–23 June 2007

1364-8535 2007 11 Suppl 3 P6 http://ccforum.com/content/11/S3/P6 10.1186/cc5793 19 6 2007 2007 BioMed Central Ltd

Objective

To describe a new experimental systemic low flow state model induced by cardiac tamponade.

Methods

Ten Large White pigs (43 ± 5 kg) were instrumented with arterial and pulmonary catheters, cystostomy and splenectomy, and a latex balloon was inserted anterior to the heart. Pigs were randomized to a shock group or a control group. The shock group had the balloon inflated with 620 ± 344 ml to keep the mean arterial blood pressure at 45–55 mmHg (mean = 49 ± 4 mmHg) for 1 hour. Hemodynamic data were collected and shown as the mean ± SD. Two-way ANOVA was used with Bonferroni's correction.

Results

During shock, the SvO₂was 34 ± 8%, the heart rate was 173 ± 36 bpm, and the stroke volume was 18 ± 12 ml/min/beat. After shock, see Table 1.

Table 1

Data

Group

Pre-shock

Post-shock

1 hour

3 hours

6 hours

P value

Mean arterial blood pressure (mmHg)

Shock

111 ± 19

76 ± 13*^,&

87 ± 22*

82 ± 10*^,&

72 ± 7*^,&

<0.001^#

Control

111 ± 16

115 ± 9

102 ± 7

97 ± 8

<0.001^$

Stroke volume (ml/min/beat)

Shock

65 ± 9

22 ± 5*^,&

44 ± 8*^,&

38 ± 12 ^&

36 ± 8^&

<0.001^#

Control

59 ± 16

59 ± 13

53 ± 7

54 ± 9

45 ± 12

<0.001^$

SVO₂(%)

Shock

73 ± 9

65 ± 8

69 ± 8

55 ± 15^&

56 ± 13^&

0.023^#

Control

75 ± 7

72 ± 6

68 ± 5^&

62 ± 6^&

0.002^$

Lactate (mg/dl)

Shock

15 ± 6

72 ± 19*^,&

51 ± 22*^,&

23 ± 19

14 ± 6

<0.001^#

Control

25 ± 13

18 ± 8

12 ± 5

17 ± 13

14 ± 10

<0.001^$

Temperature (°C)

Shock

36.8 ± 0.6

37.5 ± 0.4

38.7 ± 0.7*^,&

39.6 ± 0.7*^,&

39.7 ± 0.6*^,&

<0.001^#

Control

36.5 ± 0.3

37.0 ± 0.6

37.5 ± 0.7

38.0 ± 0.6

38.4 ± 0.4

<0.001^$

Two-way ANOVA between groups^#and within groups^$. Tukey*P < 0.05 vs control and ^&P < 0.05 vs baseline.

Conclusion

In our model, transient cardiac tamponade caused persistent hypotension and cardiovascular dysfunction. Hyperthermia was an interesting finding in the last hours of the experiment in animals submitted to cardiac tamponade.