Control of intra-abdominal pressure in severe acute pancreatitis with continuous hemodiafiltration using a polymethyl methacrylate membrane hemofilter and colloid fluid therapy

Aim

It is generally accepted that vascular permeability is increased by the pathologic effects of various humoral mediators, leading to reduction of circulating blood volume and fluid collection in the abdominal cavity, or intestinal edema in the early stage of severe acute pancreatitis (SAP). The hyperpermeability-induced pathophysiological conditions thus increase the intra-abdominal pressure (IAP), and eventually cause intra-abdominal hypertension (IAH). IAH causes organ dysfunctions such as respiratory failure, circulatory failure, and renal failure, and such a condition is referred to as abdominal compartment syndrome. If the causative humoral mediators can be removed and the vascular permeability can be normalized, the administration of oncotic agent can increase colloid osmotic pressure (COP) and reduce IAP. We have claimed that continuous hemodiafiltration using a polymethyl methacrylate membrane hemofilter (PMMA-CHDF) can remove various humoral mediators from the blood stream and that PMMA-CHDF and colloid fluid administration can reduce interstitial edema. The present study was undertaken to investigate the efficacy of PMMA-CHDF and colloid fluid therapy for the control of IAP in SAP.

Patients and methods

Fourteen patients with SAP who were treated with PMMA-CHDF and colloid fluid therapy in the period from May 2000 to December 2003 were included in this study. IAP, COP and the blood level of IL-6 were measured for the initial 3 days. The correlations between the degree of the changes in IAP (dIAP), COP (dCOP), IL-6 (dIL-6) and cumulative water balances (CWB) for the initial 3 days were investigated.

Results

There was significant and positive correlation between IAP and the blood level of IL-6 before the treatment (r = -0.75, P < 0.01). There was also significant and negative correlation between the blood level of IL-6 and COP before the treatment (r = 0.75, P < 0.01). The blood level of IL-6 significantly decreased and COP significantly increased with 3 days of PMMA-CHDF and colloid fluid therapy. IAP also decreased significantly and 380 ± 2350 ml water could be removed from the patients for the initial 3 days. There were significant and negative correlations between dCOP and dIL-6, and between dIAP and dCOP (r = -0.65, r = -0.70, P < 0.05). On the contrary, there was no significant correlation between dIAP and CWB.

Conclusions

These results indicate that IAP significantly correlates with the blood level of IL-6 and COP in patients with SAP, and that PMMA-CHDF and colloid fluid therapy can significantly decrease the blood level of IL-6, increase COP and effectively reduce IAP. We thus conclude that PMMA-CHDF and colloid fluid therapy can control IAP in patients with SAP, and that it should be applied in the early stage of SAP.