The evolution of the Helsinki frostbite management protocol.

BACKGROUND: Severe frostbite can result in devastating injuries leading to significant morbidity and loss of function from distal extremity amputation. The modern day management approach to frostbite injuries is evolving from a historically very conservative approach to the increasingly reported use of early interventional angiography and fibrinolysis with tPA. The aim of this study was to evaluate the results of our frostbite treatment protocol introduced 3 years ago. METHODS: All frostbite patients underwent first clinical and then Doppler ultrasound examination. Angiography was conducted if certain clinical criteria indicated a severe frostbite injury and if there were no contraindications to fibrinolysis. Intra-arterial tissue plasminogen activator (tPA) was then administered at 0.5-1mg/h proximal to the antecubital fossa (brachial artery) or popliteal fossa (femoral artery) if angiography confirmed thrombosis, as well as unfractionated intravenous heparin at 500 units/h. The vasodilator iloprost was administered intravenously (0.5-2.0ng/kg/min) in selected cases. RESULTS: 20 patients with frostbite were diagnosed between 2013-2016. Fourteen patients had a severe injury and angiography was performed in 10 cases. The total number of digits at risk was 111. Nine patients underwent fibrinolytic treatment with tPA (including one patient who received iloprost after initial non response to tPA), 3 patients were treated with iloprost alone and 2 patients received neither treatment modality (due to contraindications). The overall digital salvage rate was 74.8% and the Hennepin tissue salvage rate was 81.1%. One patient developed a catheter-site pseudoaneurysm that resolved after conservative treatment. CONCLUSIONS: Prompt referral to a facility where interventional radiology and 24/7 laboratory services are available, and the combined use of tPA and iloprost, may improve outcome after severe frostbite.

Matrix metalloproteinases -8 and -9 and tissue inhibitor of metalloproteinase-1 in burn patients. A prospective observational study.

INTRODUCTION: Matrix metalloproteinases (MMPs) -8 and -9 are released from neutrophils in acute inflammation and may contribute to permeability changes in burn injury. In retrospective studies on sepsis, levels of MMP-8, MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) differed from those of healthy controls, and TIMP-1 showed an association with outcome. Our objective was to investigate the relationship between these proteins and disease severity and outcome in burn patients. METHODS: In this prospective, observational, two-center study, we collected plasma samples from admission to day 21 post-burn, and burn blister fluid samples on admission. We compared MMP-8, -9, and TIMP-1 levels between TBSA<20% (N = 19) and TBSA>20% (N = 30) injured patients and healthy controls, and between 90-day survivors and non-survivors. MMP-8, -9, and TIMP-1 levels at 24-48 hours from injury, their maximal levels, and their time-adjusted means were compared between groups. Correlations with clinical parameters and the extent of burn were analyzed. MMP-8, -9, and TIMP-1 levels in burn blister fluids were also studied. RESULTS: Plasma MMP-8 and -9 were higher in patients than in healthy controls (P<0.001 and P = 0.016), but only MMP-8 differed between the TBSA<20% and TBSA>20% groups. MMP-8 and -9 were not associated with clinical severity or outcome measures. TIMP-1 differed significantly between patients and controls (P<0.001) and between TBSA<20% and TBSA>20% groups (P<0.002). TIMP-1 was associated with 90-day mortality and correlated with the extent of injury and clinical measures of disease severity. TIMP-1 may serve as a new biomarker in outcome prognostication of burn patients.