Dr Ruilong Zhao^1,2, Dr Thomas Lang¹, Dr Albert Kim², Dr Rachel McGrath², Dr Meilang Xue¹, Dr Haiyan Lin¹, Mrs Susan Smith³, Dr Siobhan Fitzpatrick², Dr Nancy Huang², Dr Andrew Zimmerman¹, Dr Aruna Wijewardena², Prof Gregory Fulcher², Dr John Vandervord², Prof Chris Jackson¹

¹Sutton Laboratory, Kolling Institute at Royal North Shore Hospital, St Leonards, Australia, ²Royal North Shore Hospital, St Leonards, Australia, ³Raymond Purves Laboratory, Kolling Institute at Royal North Shore Hospital, St Leonards, Australia

Abstract:

The natural course of some severe burns patients is difficult to predict without robust biomarkers to assist traditional evaluation. We have recently shown that plasma protein C (PC) levels are reduced following burn injuries (Lang et al. 2019). Here we elucidated PC’s potential utility as a dynamic marker of injury severity and extent, and value as an early predictor of clinical outcome.

We enrolled 86 patients in a single-centre prospective cohort study conducted at Royal North Shore Hospital in Sydney. Serial blood samples were taken and analysed for PC and a panel of six pro-inflammatory cytokines including CRP. Clinical outcome was determined by a previously described composite of fluid/ICU/surgical requirements termed “increased support”.

Plasma PC and CRP both tracked injury recovery over time. Notably, PC was markedly reduced on Day 0 before recovering to normal levels. Throughout the first 1-2 weeks, PC was consistently lower in patients with larger burns (p<0.01), deeper burns (p<0.01), and those with inhalational burns (p<0.05). Whereas in CRP these differences were not apparent until 3-6 days after injury. At baseline on Day 0, burn size (p<0.0005), depth (p<0.0005), inhalational injury (p<0.0005), and PC levels (p<0.0005) – but not any other inflammatory mediator tested – were predictors of clinical outcome. Multivariable regression showed Day 0 PC predicted increased support even when adjusted for burn size, depth and presence of inhalational injury (OR 0.879 (0.793-0.973), p=0.013), with 78.9% sensitivity and 92.3% specificity.

PC may therefore provide a simple yet powerful adjunct for assessment of the burns patient.

References

Lang, C, Zhao, R, Kim, A, Wijewardena, A, Vanderword, J, McGrath, R, Fitzpatrick, S, Fulcher, G & Jackson, C 2019, ‘Plasma protein C levels are directly associated with better outcomes in patients with severe burns’, Burns, (accepted 01/05/2019)

Biography:

Ruilong is a junior doctor and a final year PhD student based at the Royal North Shore Hospital in Sydney. There he has discovered a keen interest in burns and reconstructive surgery. His research focuses on protein C’s actions in wound healing and as a biomarker in burn injuries.