Multiorgan Dysfunction in Trauma and Surgical Intensive Care Units


Gene

Function

Study origin

Sample size

Criteria

Polymorphic sites

Clinical implications on the development of sepsis or MODS

TLR9

Pathogen recognition and activation of innate immunity

China [62]

557

Severe blunt trauma (ISS > 16); presence of at least one life-threatening injury

TLR9 polymorphisms rs187084 and rs352162

It has a trend of association with MOD score. There is significant association with TNF-α production and higher rates of sepsis morbidity

Netherlands [64]

219

Polytrauma patients with ISS ≥ 16 and age between 18 and 80 years

-1486T/C

This SNP has a trend toward reduced prevalence of gram + ve bacteria/ fungi but no significant association with SIRS, or septic shock

TNFα

Regulation immune cells and respond to sepsis via IL1, IL6 producing cells

United States [65]

152

Severe trauma, ISS ≥ 16; admitted to the ICU for more than 24 h

308G/A

TNF-α promoter increases the risk for severe sepsis and possibly for death after trauma

Germany [66]

159

Multiple trauma, age 18–65 years, ISS ≥ 12, time of admission to the ICU within 12 h of accident, >3 days of survival

rs1800629A or rs909253G

TNF gene variants are associated with sepsis syndrome and death after severe injury

United States [67]

68

Blunt and penetrating trauma with ISS ≥ 15

-308G/A

Lack of association between the TNF-α G/A or A/A high producer genotypes and sepsis

Netherlands [68]

70

Severe blunt trauma; age 18–65 years; admission <8 h after trauma or secondary admission

-308G/A

Significantly associated with development of sepsis

Latvia [69]

103

ICU patients with severe sepsis

-308G/A

TNF-α -308 A allele is not associated with a higher mortality rate in septicemic patients without shock

IL-6

To stimulate immune response, e.g., after trauma

Germany [70]

112

Critically ill patients admitted to the surgical ICU; age ≥ 18

174G/C

IL-6 -174G/C promoter genotype is associated with shock in patients with sepsis

Germany [71]

326

Severe sepsis and/or shock

174G/C

IL-6 promoter polymorphism (-174G/C) does not affect the incidence of sepsis

Latvia [69]

103

Severe sepsis

174G/C

An increased association of IL-6 -174 observed with mortality





Prediction Models of MODS


Till date several prediction models have been proposed for early detection of high-risk patients susceptible for the development of MODS. These models are crucial for the development of early interventional strategies, planning intensive care resource allocation and risk-stratification of vulnerable patient population to prevent second hit. An initial prediction model of MODS was proposed in 1998, which demonstrated shock parameters, age, ISS and platelet count as the predictor of MODS [18]. Since then efforts have been put to minimize the effect of shock through improved resuscitation strategies. Currently, early hemostatic resuscitation helped in reducing the impact of shock and now it is not considered as a predictor of MODS. A recent study [8] demonstrated age and on-admission platelet count to be independent predictors of MODS. Dewar and colleagues reported that the prediction power could be further enhanced by considering creatinine and bilirubin levels within first 24 h of admission [8]. Ciesla et al. [7] observed that ISS is ineffective in predicting MODS, as there is an injury threshold level above which MODS is likely to occur. Moreover, several investigators have identified advanced age as a marker of comorbidity and consider it as an independent predictor of the development of post-injury MODS in severe trauma patients [7, 63, 72]. An earlier study observed male gender to be an independent predictor of the development of severe infection in surgical patients [73]. Nydam et al. [74] reported thrombocytopenia (<80,000) at 12 h post admission to be an independent predictor of MODS. Consistently, Dewar et al. [8] also observed a similar association showing on-admission thrombocytopenia (<150 × 109/L) to be a significant predictor of MODS. Also, base deficit has been considered as a surrogate marker of hypovolemic shock and is used to identify patients who need early hemostatic resuscitation [75]. Regardless of MODS occurrence, base excess is a strong predictor of mortality in severely injured patients [76]. In addition, base deficit along with other significant predictors of MODS has the potential to stratify high-risk MODS patients initially during admission. A recent prospective cohort study from the USA identified male gender, preexisting liver disease, severe ISS, use of early vasopressors, higher volumes of FFP and crystalloid resuscitation, duration of shock, and more severe depth of shock (lactate values <12 h) to be the independent predictors of MODS [10].

Groeneveld et al. [77] analyzed the utility of immunomodulating interventions for the management of posttraumatic complications. The authors [77] found little significance of immune markers (cytokines) for prognosis of MODS due to lower sensitivity and specificity. Another recent promising approach to predict MODS is the assessment of immune cell functionality. It has been shown that phenotyping of blood Polymorphonuclear granulocytes (PMNs) in post-injury patients help to estimate the kinetics and extent of initial SIRS [78]. Furthermore, it has been observed that prior to sepsis development the PMNs functionality reaches its minimum level, so this approach could be used for determining the high-risk patients at earlier stage [79]. Recently, Anne Morrison et al. [80] demonstrated that trauma patients with hemorrhagic shock who had higher PMN apoptosis are at reduced risk of tissue injury and susceptibility to infection which might lead to MODS.

Based on the available predictors, to some extent MODS can be predicted at early stage after injury and so early prevention and treatment could be initiated at this point [18]. Particularly, a reliable prediction model might be supportive for patient recruitment and inclusion in trauma studies, in which MODS marks the primary end point. Finally, identification of major risk factors and predictors helps to stratify and enroll patients for clinical trials during the initial phase of trauma care and surgery. It also supports the assessment of quantifiable outcome of trials in critical ill patients. Although, numerous studies have focused on MODS, majority of prediction models have restricted applicability which may be attributed to the genetic variation among the individual trauma and surgery patients. Therefore, current studies based on genetic predisposition of multiple trauma and surgery patients will favorably improve these prediction models and will enhance their applicability in the near future [81].


Management of MODS Patients


Over the years extensive clinical and experimental studies have been performed for early detection and treatment of post-injury MODS, however it remains a challenging issue for the emergency physicians and trauma surgeons. The current management strategies of high-risk MODS patients are mainly based on preventive and therapeutic interventions.


Preventive Strategies


In trauma patients, preventive strategies usually focus on pre-injury (such as controlling severity of injuries, and limiting the intensity and duration of prehospital shock) and post-injury (to prevent secondary insults) phases, whereas the management strategies in surgical ICU patients mainly depend upon the postoperative course. The rate of post-injury and postoperative MODS could be minimized through improvement in metabolic defects and early hemostatic resuscitation among high-risk population [54]. Moreover, proper mechanical ventilation, antibiotic use, early nutritional support, detection of missed injuries and continuous monitoring for septic complications could be useful for reducing the risk of MODS [54]. O’Brien [82] showed that the risk of developing acute respiratory distress syndrome (ARDS) and MODS could also be minimized by early fixation of major orthopedic injuries in multiple trauma patients. During early phase of injury, the triad of hypothermia, coagulopathy, and acidosis is harmful for severe trauma patients, and such patients are at increased risk of MODS [3]. Therefore, early posttraumatic complications could be mitigated or prevented through rapid hemorrhage control, proper resuscitation, and correction of coagulopathy. Moreover, rapid prehospital transport, early hemostatic resuscitation, and minimal use of blood products might help in reducing the duration and severity of shock which controls PMN priming and decrease the risk of developing MODS post-injury [7]. Johnson et al. [83] investigated the association between red cell substitute and hyperinflammatory response in post-injury patients. The authors found that patients treated with red cell substitutes had lower immunological response (IL6, IL8, and IL10) than those treated with packed red blood cells [83]. The approach of damage control surgery particularly in orthopedics have been recognized in reducing the delayed initial surgery (act as second hits in primed patients) and the risk of developing MODS [1]. A number of factors are found to reduce the development of MOF and or improve the outcomes of MODS patients. These include improvement in critical care medicine facilities, modernization of ICUs, timely recognition of missed injuries, lung protective ventilation strategies, optimal timing of surgery, early enteral nutrition, and renal replacement therapies [1]. Therefore, the primary objective of these therapies is to prevent MODS in critically ill patients.


Therapeutic Strategies


For better prognosis of MODS patients, several therapeutic strategies have been developed to modulate the inflammatory response. The current therapeutic options are mainly focused on modulating the detrimental effects of the exaggerated immune system and at the same time maintaining favorable host immune response. Particularly, timing of intervention is a crucial factor for appropriate modulation of immune response in high-risk sepsis and MODS patients [84]. A variety of targets has been identified to develop therapeutic interventions which range from exogenous trigger (endotoxin or bacterial infection), systemic mediators (such as IL-1, TNF-α), effector cell (e.g., the neutrophil), to specific target cell (the endothelium) [54]. Despite current therapeutic advancement, MODS remains a deadly syndrome. So, in order to limit secondary damage and degeneration in severely injured patients, damage control surgery has been implemented as a preferred therapeutic intervention [9].

Administration of C1-esterase inhibitor (acute-phase protein) is another promising approach to reduce the levels of circulating pro-inflammatory cytokines. Recently, CAESAR study identified C1-esterase inhibitor to be a safe and strong anti-inflammatory agent which is capable of controlling systemic inflammation among trauma patients [85].

It has been observed that immunomodulation strategies are often useful for modulating the favorable changes in the inflammatory response. A recent systematic review analyzed the implications of various immunomodulative strategies on the outcomes of severe trauma patients [86]. Even though the authors found reduction of immune response by many interventions, effective decline in infectious complications and mortality was only observed by the use of immunoglobulin, IFN-γ, or glucan. Moreover, it has been observed that the levels of circulating IgG are reduced in trauma patients. Douzinas et al. [87] demonstrated that the administration of exogenous immunoglobulins improves IgG-mediated antigen presentation which in turn modulates favorable immune response. Earlier studies reported that the administration IgG (0.25–1.0 g/kg) together with antibiotics is effective in lowering the infection in trauma patients [87, 88]. Similarly, IFN-γ induces antigen presentation to lymphocytes and two studies have reported a positive response of administrating exogenous IFN-γ (100 μg daily) on reducing rate of infection [89] and mortality [90].

Glucan, (a component of the inner cell wall of yeast), reduces prostaglandin discharge by macrophages and triggers bone marrow proliferation which improves immune response during late immune paralysis [91]. Earlier studies have suggested that the administration of Glucan (50 mg/m2 daily [91] or 30 mg every 12 h [92]) demonstrated significant reduction in the rates of infectious complications and mortality in severe trauma patients.

Interestingly, many novel therapeutic modalities have been investigated in clinical trials, but most of them failed to demonstrate efficacy in large-scale, randomized clinical trials. Therefore, use of combination therapy appears to be effective approach in minimizing infectious complications and improving survival rate among severely ill patients.


Conclusions


Although, there is a considerable improvement in the understanding of the underlying mechanism, MODS remains the main cause of resource utilization in surgical and trauma ICUs and had greater burden of morbidity and late mortality. It has been speculated that several predictors of MODS development among surgery and trauma patients might remain unidentified which mandate further exploration based on clinical and experimental studies. Moreover, further understanding of MODS mechanisms will provide better management option which will improve trauma care. Understanding the pathophysiology of early MODS will discriminate the signs of intense inflammatory response from early signs of sepsis. This will reduce the inappropriate use of antibiotics and guide the judicious therapy at the early stages of sepsis and subsequently reduce hospital stay and mortality. Furthermore, there is a need for newer therapeutic strategies for early detection of MODS and risk-stratification of trauma and surgical ICU patients using biomarker based prospective studies. Till date, implications of the efficacy of immune modulating therapies in trauma patients are not well explored. Therefore, advanced research focusing on the implications of novel immunomodulation strategies based on steroid therapy might be useful for minimizing the risk of MODS in multiple trauma and surgery patients.


References



1.

Dewar D, Moore FA, Moore EE, Balogh Z. Postinjury multiple organ failure. Injury. 2009;40:912–8.CrossRefPubMed


2.

Maier B, Lefering R, Lehnert M, Laurer HL, Steudel WI, Neugebauer EA, Marzi I. Early versus late onset of multiple organ failure is associated with differing patterns of plasma cytokine biomarker expression and outcome after severe trauma. Shock. 2007;28:668–74.PubMed


3.

Dewar D, Butcher N, King K, Balogh Z. Post injury multiple organ failure. Trauma. 2011;13:81–91.CrossRef


4.

Ciesla DJ, Moore EE, Johnson JL, Sauaia A, Cothren CC, Moore JB, Burch JM. Multiple organ dysfunction during resuscitation is not postinjury multiple organ failure. Arch Surg. 2004;139:590–4.CrossRefPubMed


5.

Ciesla DJ, Moore EE, Johnson JL, Burch JM, Cothren CC, Sauaia A. The role of the lung in postinjury multiple organ failure. Surgery. 2005;138:749–57.CrossRefPubMed


6.

Moore FA, Sauaia A, Moore EE, Haenel JB, Burch JM, Lezotte DC. Postinjury multiple organ failure: a bimodal phenomenon. J Trauma. 1996;40:501–2.CrossRefPubMed


7.

Ciesla DJ, Moore EE, Johnson JL, Burch JM, Cothren CC, Sauaia A. A 12-year prospective study of postinjury multiple organ failure: has anything changed? Arch Surg. 2005;140:432–8.CrossRefPubMed


8.

Dewar DC, Tarrant SM, King KL, Balogh ZJ. Changes in the epidemiology and prediction of multiple-organ failure after injury. J Trauma Acute Care Surg. 2013;74(3):774–9.CrossRefPubMed


9.

van Wessem KJP, Leenen LPH. The effect of evolving trauma care on the development of multiple organ dysfunction syndrome. Eur J Trauma Emerg Surg. 2014;40:127–34.CrossRef


10.

Minei JP, Cuschieri J, Sperry J, Moore EE, West MA, Harbrecht BG, O’Keefe GE, Cohen MJ, Moldawer LL, Tompkins RG, et al. The changing pattern and implications of multiple organ failure after blunt injury with hemorrhagic shock. Crit Care Med. 2012;40:1129–35.PubMedCentralCrossRefPubMed

Only gold members can continue reading. Log In or Register to continue

Oct 28, 2016 | Posted by in CRITICAL CARE | Comments Off on Multiorgan Dysfunction in Trauma and Surgical Intensive Care Units

Full access? Get Clinical Tree

Get Clinical Tree app for offline access