Immunoreactive trypsin in the adult respiratory distress syndrome

Defining polytrauma by abbreviated injury scale ≥ 3 for a least two body regions is insufficient in terms of short-term outcome: A cross-sectional study at a level I trauma center

Background

Patients with polytrauma are expected to have a higher risk of mortality than the summation of expected mortality for their individual injuries. This study was designed to investigate the outcome of polytrauma patients, diagnosed by abbreviated injury scale (AIS) ≥ 3 for at least two body regions, at a level I trauma center.

Methods

Detailed data of 694 polytrauma patients and 2104 non-polytrauma patients with an overall Injury Severity Score (ISS) ≥ 16 and hospitalized between January 1, 2009, and December 31, 2014 for treatment of all traumatic injuries, were retrieved from the Trauma Registry System. Two-sided Fisher exact or Pearson chi-square tests were used to compare categorical data. The unpaired Student t-test was used to analyze normally distributed continuous data, and the Mann–Whitney U-test was used to compare non-normally distributed data. Propensity-score matching in a 1:1 ratio was performed using NCSS software with logistic regression to evaluate the effect of polytrauma on in-hospital mortality.

Results

There was no significant difference in short-term mortality between polytrauma and non-polytrauma patients, regardless of whether the comparison was made among the total patients (11.4% vs. 11.0%, respectively; p = 0.795) or among the selected propensity score-matched groups of patients following controlled covariates including sex, age, systolic blood pressure, co-morbidities, Glasgow Coma Scale scores, injury region based on AIS.

Conclusions

Polytrauma defined by AIS ≥3 for at least two body regions failed to recognize a significant difference in short-term mortality among trauma patients.

Auxiliary activation of the complement system and its importance for the pathophysiology of clinical conditions

Activation and regulation of the cascade systems of the blood (the complement system, the coagulation/contact activation/kallikrein system, and the fibrinolytic system) occurs via activation of zymogen molecules to specific active proteolytic enzymes. Despite the fact that the generated proteases are all present together in the blood, under physiological conditions, the activity of the generated proteases is controlled by endogenous protease inhibitors. Consequently, there is remarkable little crosstalk between the different systems in the fluid phase. This concept review article aims at identifying and describing conditions where the strict system-related control is circumvented. These include clinical settings where massive amounts of proteolytic enzymes are released from tissues, e.g., during pancreatitis or post-traumatic tissue damage, resulting in consumption of the natural substrates of the specific proteases and the available protease inhibitor. Another example of cascade system dysregulation is disseminated intravascular coagulation, with canonical activation of all cascade systems of the blood, also leading to specific substrate and protease inhibitor elimination. The present review explains basic concepts in protease biochemistry of importance to understand clinical conditions with extensive protease activation.

Polytrauma Defined by the New Berlin Definition: A Validation Test Based on Propensity-Score Matching Approach

Background: Polytrauma patients are expected to have a higher risk of mortality than that obtained by the summation of expected mortality owing to their individual injuries. This study was designed to investigate the outcome of patients with polytrauma, which was defined using the new Berlin definition, as cases with an Abbreviated Injury Scale (AIS) ≥ 3 for two or more different body regions and one or more additional variables from five physiologic parameters (hypotension [systolic blood pressure ≤ 90 mmHg], unconsciousness [Glasgow Coma Scale score ≤ 8], acidosis [base excess ≤ -6.0], coagulopathy [partial thromboplastin time ≥ 40 s or international normalized ratio ≥ 1.4], and age [≥70 years]). Methods: We retrieved detailed data on 369 polytrauma patients and 1260 non-polytrauma patients with an overall Injury Severity Score (ISS) ≥ 18 who were hospitalized between 1 January 2009 and 31 December 2015 for the treatment of all traumatic injuries, from the Trauma Registry System at a level I trauma center. Patients with burn injury or incomplete registered data were excluded. Categorical data were compared with two-sided Fisher exact or Pearson chi-square tests. The unpaired Student t-test and the Mann-Whitney U-test was used to analyze normally distributed continuous data and non-normally distributed data, respectively. Propensity-score matched cohort in a 1:1 ratio was allocated using the NCSS software with logistic regression to evaluate the effect of polytrauma on patient outcomes. Results: The polytrauma patients had a significantly higher ISS than non-polytrauma patients (median (interquartile range Q1-Q3), 29 (22-36) vs. 24 (20-25), respectively; p < 0.001). Polytrauma patients had a 1.9-fold higher odds of mortality than non-polytrauma patients (95% CI 1.38-2.49; p < 0.001). Compared to non-polytrauma patients, polytrauma patients had a substantially longer hospital length of stay (LOS). In addition, a higher proportion of polytrauma patients were admitted to the intensive care unit (ICU), spent longer LOS in the ICU, and had significantly higher total medical expenses. Among 201 selected propensity score-matched pairs of polytrauma and non-polytrauma patients who showed no significant difference in sex, age, co-morbidity, AIS ≥ 3, and Injury Severity Score (ISS), the polytrauma patients had a significantly higher mortality rate (OR 17.5, 95% CI 4.21-72.76; p < 0.001), and a higher proportion of patients admitted to the ICU (84.1% vs. 74.1%, respectively; p = 0.013) with longer stays in the ICU (10.3 days vs. 7.5 days, respectively; p = 0.003). The total medical expenses for polytrauma patients were 35.1% higher than those of non-polytrauma patients. However, there was no significant difference in the LOS between polytrauma and non-polytrauma patients (21.1 days vs. 19.8 days, respectively; p = 0.399). Conclusions: The findings of this propensity-score matching study suggest that the new Berlin definition of polytrauma is feasible and applicable for trauma patients.

Update on the definition of polytrauma

PURPOSE

The definition and use of the term "polytrauma" is inconsistent and lacks validation. This article describes the historical evolution of the term and geographical differences in its meaning, examines the challenges faced in defining it adequately in the current context, and summarizes where the international consensus process is heading, in order to provide the trauma community with a validated and universally agreed upon definition of polytrauma.

CONCLUSION

A lack of consensus in the definition of "polytrauma" was apparent. According to the international consensus opinion, both anatomical and physiological parameters should be included in the definition of polytrauma. An Abbreviated Injury Scale (AIS) based anatomical definition is the most practical and feasible given the ubiquitous use of the system. Convincing preliminary data show that two body regions with AIS >2 is a good marker of polytrauma-better than other ISS cutoffs, which could also indicate monotrauma. The selection of the most accurate physiological parameters is still underway, but they will most likely be descriptors of tissue hypoxia and coagulopathy.

The definition of polytrauma: the need for international consensus

INTRODUCTION

Polytrauma patients represent the ultimate challenge to trauma care and the optimisation of their care is a major focus of clinical and basic science research. A universally accepted definition for polytrauma is vital for comparing datasets and conducting multicentre trials. The purpose of this review is to identify and evaluate the published definitions of the term "polytrauma".

MATERIALS AND METHODS

A literature search was conducted for the time period January 1950-August 2008. The Medline, Embase and Cochrane Library databases were searched using the keyword "polytrauma". Articles were evaluated without language exclusion for the occurrence of the word "polytrauma" in the text and the presence of a subsequent definition. Relevant online resources and medical dictionaries were also reviewed.

RESULTS

A total of 1,665 publications used the term polytrauma, 47 of which included a definition of the term. The available definitions can be divided into eight groups according to the crux of the definition. No uniformly used consensus definition exists. None of the existing definitions were found to be validated or supported by evidence higher than Level 4.

CONCLUSION

This review identified the lack of a validated or consensus definition of the term polytrauma. The international trauma community should consider establishing a consensus definition for polytrauma, which could be validated prospectively and serve as a basis for future research.

Pancreatic cellular injury after cardiac surgery with cardiopulmonary bypass: frequency, time course and risk factors

Although often clinically silent, pancreatic cellular injury (PCI) is relatively frequent after cardiac surgery with cardiopulmonary bypass; and its etiology and time course are largely unknown. We defined PCI as the simultaneous presence of abnormal values of pancreatic isoamylase and immunoreactive trypsin (IRT). The frequency and time evolution of PCI were assessed in this condition using assays for specific exocrine pancreatic enzymes. Correlations with inflammatory markers were searched for preoperative risk factors. One hundred ninety-three patients submitted to cardiac surgery were enrolled prospectively. Blood IRT, amylase, pancreatic isoamylase, lipase, and markers of inflammation (alpha1-protease inhibitor, alpha2-macroglobulin, myeloperoxidase) were measured preoperatively and postoperatively until day 8. The postoperative increase in plasma levels of pancreatic enzymes and urinary IRT was biphasic in all patients: early after surgery and later (from day 4 to 8 after surgery). One hundred thirty-three patients (69%) experienced PCI, with mean IRT, isoamylase, and alpha1-protease inhibitor values higher for each sample than that in patients without PCI. By multiple regression analysis, we found preoperative values of plasma IRT >or=40 ng/mL, amylase >or=42 IU/mL, and pancreatic isoamylase >or=20 IU/L associated with a higher incidence of postsurgery PCI (P < 0.005). In the PCI patients, a significant correlation was found between the 4 pancreatic enzymes and urinary IRT, total calcium, myeloperoxidase, alpha1-protease inhibitor, and alpha2-macroglobulin. These data support a high prevalence of postoperative PCI after cardiac surgery with cardiopulmonary bypass, typically biphasic and clinically silent, especially when pancreatic enzymes were elevated preoperatively.

Compartmentalization of the protease-antiprotease balance in early severe acute pancreatitis

OBJECTIVE

To assess the balance between trypsin and protease inhibitors simultaneously in the systemic circulation and in the thoracic lymph and peritoneal exudate.

METHODS

Twenty patients with early severe acute pancreatitis were studied. Enzymatically active and immunoreactive trypsin in conjunction with its major inhibitors were measured in the 3 compartments at the onset of end-organ failure(s). The molecular forms of trypsin were determined in the lymph and ascites by gel filtration chromatography to separate trypsinogen and free-and inhibitor-bound trypsin.

RESULTS

Both enzymatically active trypsin and immunoreactive trypsin levels were highest in ascites and lymph compared with the systemic circulation. Intracompartmental alpha1- protease inhibitor gradient moved in the opposite direction, whereas alpha2 macroglobulin concentration was highest in ascites and lowest in the lymph. Although most of the enzymatically and immunoreactive material in ascites and lymph consisted of trypsin complexed with alpha2 macroglobulin and trypsinogen, respectively, free active trypsin was detected in more than 80% of the samples.

CONCLUSIONS

In patients with early severe acute pancreatitis, there is a significant trypsinogen activation resulting in protease-antiprotease imbalance and thereby free enzymatically active trypsin in the 2 body fluid compartments in close vicinity to the inflammatory process. This may be involved in the pathophysiology of local and distant tissue damage.

Pancreatic injury in equine acute abdomen evaluated by plasma trypsin activity and histopathology of pancreatic tissue

In cases of equine acute abdominal disease, where pancreatic damage is suspected, pancreatic damage can be assessed by measuring increased trypsin activity in the plasma of horses suffering intestinal obstruction and severe shock. The pancreas is particularly vulnerable to splanchnic hypoperfusion because it is a highly active tissue. In this study, 10 horses undergoing abdominal surgery for intestinal obstruction were assayed for trypsin activity on admission and, because of extensive intestinal lesions that were not amenable to surgery, euthanasia was selected; the pancreas was removed before euthanasia. Trypsin activity in the plasma of these horses was significantly higher than in healthy horses (196 ng/ml +/- 128.2 versus 28.5 ng/ml +/- 19.2; P = 0.0026). Light and transmission electron microscopy revealed slight to severe lesions of vacuolar degeneration, a few zymogen granules, dilation of the endoplasmic reticulum, and swelling of mitochondria in the exocrine pancreas. The activation of an inflammatory cascade occurring during strangulating intestinal obstruction could increase pancreatic anoxic lesions caused by severe shock and hypoperfusion in the horse. Further studies will show the significance of pancreatic lesions and the ensuing damage in equine acute intestinal obstruction and shock.

Plasma trypsin level in horses suffering from acute intestinal obstruction

Gastrointestinal disorders in horses leading to endotoxic shock could have further consequences on other splanchnic organs such as the pancreas, as can be seen in humans suffering from septic shock. In this study, the range of enzymatically active trypsin (EAT) in healthy horses was established and is similar to the range observed in healthy humans. EAT values were determined in horses with acute abdominal crises on admission as well as during anaesthesia and in the postoperative phase. A significant increase in plasma EAT was found in 59% of the horses with surgical colic when compared to our established reference range. Significantly higher values were found in severe shock cases. When separated in groups according to the duration of colic before referral, significantly higher EAT values were observed in the non-survivor group compared to the survivor group of colics of short duration. EAT plasma values increased significantly during the postoperative phase, and were significantly higher in small intestine obstructions than in large bowel disorders. In human medicine, hypovolaemic or septic shock patients show an increase in pancreatic proteases. Splanchnic hypoperfusion during shock could lead to pancreatic damage resulting in trypsin liberation into the peritoneal space and an increase in plasma levels. Trypsin is able to activate inflammatory cascades and leucocytes and could play a role in multiple organ failure. Further studies are needed to evaluate the implications of changes in plasma trypsin in the disease process of equine acute abdomen and to demonstrate possible pancreatic damage.

Hemorrhagic shock and encephalopathy syndrome

Hemorrhagic shock and encephalopathy syndrome (HSES) is a devastating symptom complex that affects previously healthy infants and is associated with significant mortality and neurologic morbidity. The syndrome was first reported less than ten years ago, and there continues to be debate regarding whether HSES actually represents a distinct clinical entity or instead is a manifestation of heat illness, occult sepsis or endotoxic shock, or perhaps toxic ingestion. Nevertheless, the signs and symptoms described as HSES present in a typical fashion in the emergency department with sudden onset of shock, encephalopathy, seizures, and coagulopathy. Even with the initiation of intensive support in the ED, the outcome is probably dismal. We describe a case of HSES and review the presentation, proposed etiologies, and management of this catastrophic illness.

Acute pancreatitis

This paper provides a review of recent advances in the understanding and management of acute pancreatitis. The mortality of acute severe pancreatitis remains disappointingly high. While there have been relatively few recent advances in the surgical management of acute pancreatitis, several nonsurgical developments appear promising.