Definition, epidemiology and characterization of sepsis

INTRODUCTION

Sepsis, a life-threatening condition caused by the body's response, to infection, continues to be a topic in medical research.¹ Over the years our understanding of sepsis and how it works has evolved, reflecting advancements in our knowledge of its nature. We now recognize sepsis as a condition where the body's response to infection becomes dysregulated leading to organ dysfunction.^2,3 The immune system plays a role in sepsis with imbalances in anti-inflammatory responses potentially causing multiple organ failure. From a standpoint sepsis presents a global health challenge.⁴

It affects millions of people every year. Is one of the leading causes of death due to its high mortality rate. The incidence of sepsis is increasing due to factors such as an aging population, higher prevalence of diseases and infections acquired during healthcare procedures.⁵ Numerous studies have investigated the epidemiology of sepsis shedding light on its occurrence rates risk factors and outcomes. Sepsis is not limited to hospitals many cases originate from infections acquired within communities.^6,7 Understanding the manifestations of sepsis is crucial as they can vary greatly from mild systemic inflammatory response syndrome (SIRS) to severe forms, like septic shock. Early recognition and timely intervention play roles in improving patient outcomes.⁸

Biomarkers like procalcitonin and lactate have been widely researched for their ability to diagnose and predict the outcome of sepsis. Imaging techniques, such, as ultrasound and computed tomography help identify the origin of infection.^9,10 Evaluate how organs are functioning. In sepsis an intricate interaction, between cytokines, chemokines and immune cells coordinates the response. The disruption of the balance, between inflammatory and anti-inflammatory substances contributes to the progression of sepsis.¹¹ Sepsis pathophysiology has received attention due to the involvement of the endothelium, coagulation cascade and cellular metabolism highlighting how complex this syndrome is. Dealing with the aspect of sepsis involves identifying the specific pathogens responsible and customizing therapy accordingly.^12,13

The emergence of resistance adds another layer of complexity to managing sepsis requiring an approach to antibiotic usage. Recent literature explores strategies like precision medicine and host directed therapies in order to improve the accuracy and effectiveness of sepsis treatment. The long-term consequences of sepsis, often referred to as sepsis syndrome, are gaining recognition. Survivors may experience inflammation, dysregulation and cognitive impairment highlighting the importance of comprehensive follow up care. Exploring how sepsis impacts health and quality of life is an emerging area in research. The intricate interplay between response microbial factors and host pathogen interactions underscores the complexity involved in sepsis pathophysiology.^14,15 Given its impact on health continuous research is necessary, for advancing tools, therapeutic approaches and long-term care strategies. The reason for conducting this review is to explore sepsis and gain an understanding of its complex nature as a critical medical condition. This review aims to provide an overview of the definition, epidemiology and characterization of sepsis.

METHODS

On 26 November 2023, we conducted an examination of articles, from Cochrane Library, Pubmed and Scopus. Our analysis focused on understanding sepsis by looking at its definition, epidemiology and characteristics. We specifically looked at studies conducted in English since 2008 that aimed to provide an understanding of sepsis. The goal of this review is to offer healthcare professionals insights into assessment methods and early warning systems that can improve safety in cases of sepsis.

DISCUSSION

The symptoms of sepsis can. Are influenced by how the body’s immune response interacts with the invading pathogen. Initially there is a phase called SIRS which is characterized by specific signs, like fever or hypothermia, fast heartbeat, rapid breathing and changes in white blood cell count. These symptoms indicate that the immune response to an infection is not working correctly. It's important to identify sepsis because it can progress rapidly and requires assessment. Sepsis puts a lot of strain on the system causing blood pressure and problems with blood flow, which can indicate septic shock. The respiratory system is also affected, ranging from difficulty breathing to acute respiratory distress syndrome (ARDS) that needs advanced ventilation support.¹⁶ Neurological symptoms like confusion show that multiple organs are involved in sepsis. Gastrointestinal issues and skin problems also contribute to the picture showing how sepsis affects the whole body. Laboratory tests play a role in diagnosing sepsis by looking at things, like blood cell count, inflammation markers and clotting abnormalities. These test results do not confirm the diagnosis. Also help guide ongoing treatment strategies. The multifaceted nature of sepsis calls for a team approach, where healthcare providers work together to manage the presentations effectively.

Clinical manifestation

Sepsis, which occurs when the body's response to an infection becomes dysregulated is an emergency that requires timely diagnosis and intervention. It can have manifestations and is associated with high mortality rates.^17,18 When sepsis begins it initiates a chain of reactions that are prompted by infections caused by bacteria, viruses, fungi or parasites. The clinical signs of sepsis can vary greatly in severity and presentation making it crucial to identify it early as prompt intervention significantly affects outcomes. SIRS is a stage that occurs during the progression of sepsis. It is characterized by symptoms, like fever or low body temperature rapid heartbeat (tachycardia) accelerated breathing (tachypnea) and abnormal white blood cell count (leukocytosis or leukopenia). These signs indicate how the body reacts to an infection. When the body temperature goes above 38°C (100.4°F) or drops below 36°C (96.8°F) it signals the presence of sepsis. This highlights the importance of monitoring. Sepsis affects the body’s system resulting in symptoms like blood pressure (hypotension) increased heart rate (tachycardia) and altered blood flow, throughout the body. Hypotension that does not improve with resuscitation indicates shock—a severe form of sepsis. The compromised cardiovascular function results in tissue perfusion ultimately leading to organ dysfunction. Respiratory symptoms, in sepsis can vary from breathing to severe acute respiratory distress syndrome (ARDS). It is not uncommon to experience increased breathing rates, shortness of breath and low oxygen levels. ARDS, which involves inflammation, throughout the lungs can escalate quickly requiring ventilator assistance to ensure oxygen supply.¹⁹ The central nervous system is often impacted by sepsis resulting in changes to function. Confusion, delirium or even a state of unconsciousness can be observed, indicating the impact caused by substances and dysfunction, in the small blood vessels. This clearly shows that sepsis affects organs. The gastrointestinal system is significantly affected during sepsis leading to symptoms like pain feelings of nausea, vomiting and diarrhea.²⁰

In cases there can be damage to the integrity of the gut, which allows bacteria and toxins to enter the bloodstream and worsen the inflammatory response in the body. Cutaneous manifestations are quite common. Often appear as purplish discoloration on the skin. The skin may also appear pale or bluish due to circulation in blood vessels. Development of spots (petechiae) or larger bruises (ecchymosis) indicates potential problems with blood clotting and disseminated intravascular coagulation (DIC) which is a serious complication in severe cases of sepsis. Laboratory results are important for diagnosing and monitoring sepsis. They can reveal indications such as lower blood cell counts (leukocytosis or leukopenia) elevated levels of markers like C reactive protein and procalcitonin as well as abnormalities in blood clotting, such, as low platelet count (thrombocytopenia) and prolonged clotting times. These abnormal findings help doctors diagnose sepsis accurately and guide management strategies for treatment. Therefore, sepsis presents itself through manifestations that reflect how an uncontrolled immune response to an infection impacts the entire body systemically.

Recognizing signs such as meeting SIRS criteria fluctuations in body temperature cardiovascular issues, breathing difficulties like distress changes in mental status gastrointestinal symptoms like abdominal pain along with nausea/vomiting/diarrhea patterns seen together skin changes and abnormalities found in laboratory tests are all crucial, in ensuring timely diagnosis and intervention. Due to the advancement of sepsis, it is extremely important to have a suspicion and quickly assess the patient’s clinical condition. The fact that sepsis can present in ways highlights its nature, which emphasizes the need for a collaborative and interdisciplinary approach in managing this condition.

Management

Sepsis is a condition where the body's response to infection becomes unbalanced. Managing sepsis requires a multidisciplinary approach. As our understanding of sepsis has evolved so have the strategies used to treat it. The goal is to reduce the response address the infection and provide necessary supportive care. Recognizing sepsis early is crucial for intervention and better outcomes. Clinical indicators, like the SIRS assist in identifying patients who may be at risk.²¹

Biomarkers such as procalcitonin and lactate aid, in the diagnosis of sepsis.²² They are implementing tools and protocols aids in early identification allowing healthcare professionals to initiate timely interventions. Treating sepsis requires the identification and management of the infection. Measures like draining abscesses, removing tissues or extracting infected devices significantly contribute to controlling the source of infection. Prompt administration of antibiotics guided by pathogens and local resistance patterns improves survival rates. Sepsis often causes instability, which requires support. Swift fluid resuscitation with crystalloids helps address hypovolemia while vasopressors like norepinephrine maintain perfusion, in cases of low blood pressure seen in septic shock. The main objective of goal directed therapy is to optimize the functioning of the bodys circulation while ensuring that it doesn't get overloaded with fluids. Managing respiratory failure caused by sepsis is critically important. Providing support for breathing plays a role in doing so. Sometimes when someone is experiencing acute respiratory distress syndrome (ARDS) it might be required to utilize ventilation.

Lung protective ventilation strategies are employed to preserve lung health, which includes using volumes minimizing damage caused by the ventilator and applying positive end expiratory pressure (PEEP) to maintain proper oxygenation and alveolar recruitment. The use of corticosteroids in sepsis treatment is a topic of debate. In cases where maintaining stability is challenging low dose corticosteroids may be considered. However, their usage requires consideration of selection to balance potential benefits against possible adverse effects. Researchers have explored the use of agents, like immunoglobulin (IVIG) and recombinant human activated protein C (rhAPC) for their potential, in the treatment of sepsis. Their effectiveness is still not universally established. Typically, these agents are reserved for situations or investigational purposes. Acute kidney injury often occurs as a complication of sepsis and severe cases may require replacement therapy such as venovenous hemofiltration (CVVH) or intermittent hemodialysis to address fluid balance issues, electrolyte abnormalities and uremia. Maintaining control is crucial in managing sepsis due to the negative outcomes associated with hyperglycemia. Insulin therapy is initiated to achieve target glucose levels while closely monitoring to prevent hypoglycemia from occurring.

Sepsis increases the risk of events leading to the implementation of anticoagulant thromboprophylaxis measures. However, it is important to consider the equilibrium between preventing blood clotting and avoiding bleeding complications especially when dealing with critically ill patients. It is crucial to acknowledge the lasting effects of sepsis such as intensive care syndrome (PICS) and post sepsis syndrome. To ensure follow-up care it is essential to address the cognitive and psychological consequences of these conditions. This includes integrating rehabilitation efforts, like therapy and occupational therapy into the management of sepsis recovery. The management of sepsis is quite complex.

Requires an effort from various healthcare professionals. It's important to have discussions involving intensivists, disease specialists, pharmacists, respiratory therapists, and others to ensure comprehensive care for patients. Ongoing research is focused on discovering treatment approaches and refining existing strategies. Researchers are currently conducting trials to investigate how well medications, immunotherapies, and precision medicine methods can be used to treat sepsis. To sum up, the clinical management of sepsis involves the detection and targeted use of drugs providing hemodynamic and respiratory support, when necessary, carefully using immunomodulatory therapies and adopting a comprehensive multidisciplinary approach. The field of research is constant. Shaping the way, we treat this life-threatening condition by emphasizing the importance of dynamic approaches based on evidence, for achieving optimal outcomes.

CONCLUSION

Sepsis remains a topic in our study as it involves the body's uncontrolled response to infection. The clinical signs range from meeting SIRS criteria to experiencing sepsis and septic shock highlighting the importance of detection and intervention. The evolving understanding of how sepsis affects the body has influenced treatment approaches emphasizing the need for a collaborative method. Managing sepsis includes identifying it providing targeted therapy offering hemodynamic and respiratory support and using immunomodulatory therapies cautiously. Ongoing research advancements continue to refine existing strategies contributing to the changing landscape of managing sepsis. It is crucial to provide follow-up care that acknowledges the long-term effects of sepsis on survivor's physical, cognitive, and psychological well-being. Given the health impact of sepsis continuous research is necessary to improve diagnostic tools, treatment approaches, and long-term care strategies that consider the various dimensions of this critical medical condition.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: Not required

REFERENCES

1. 1. Wu AL, Wu WC. Anti-VEGF for ROP and Pediatric Retinal Diseases. Asia Pac J Ophthalmol (Phila). 2018;7(3):145-51.
2. 2. Delano MJ, Ward PA. The immune system's role in sepsis progression, resolution, and long-term outcome. Immunol Rev. 2016;274(1):330-3.
3. 3. Fujishima S. Organ dysfunction as a new standard for defining sepsis. Inflamm Regen. 2016;36:24.
4. 4. Chen J, Wei H. Immune Intervention in Sepsis. Front Pharmacol. 2021;12:718089.
5. 5. Mayr FB, Yende S, Angus DC. Epidemiology of severe sepsis. Virulence. 2014 ;5(1):4-11.
6. 6. Lin GL, McGinley JP, Drysdale SB, Pollard AJ. Epidemiology and Immune Pathogenesis of Viral Sepsis. Front Immunol. 2018;9:2147.
7. 7. Suleyman G, Alangaden G, Bardossy AC. The Role of Environmental Contamination in the Transmission of Nosocomial Pathogens and Healthcare-Associated Infections. Curr Infect Dis Rep. 2018;20(6):12.
8. 8. Polat G, Ugan RA, Cadirci E, Halici Z. Sepsis and Septic Shock: Current Treatment Strategies and New Approaches. Eurasian J Med. 2017;49(1):53-8.
9. 9. Vijayan AL, Vanimaya, Ravindran S, Saikant R, Lakshmi S, Kartik R, et al. Procalcitonin: a promising diagnostic marker for sepsis and antibiotic therapy. J Intensive Care. 2017;5:51.
10. 10. Ozbay S, Ayan M, Ozsoy O, Akman C, Karcioglu O. Diagnostic and Prognostic Roles of Procalcitonin and Other Tools in Community-Acquired Pneumonia: A Narrative Review. Diagnostics (Basel). 2023;13(11):1869.
11. 11. Venet F, Monneret G. Advances in the understanding and treatment of sepsis-induced immunosuppression. Nat Rev Nephrol. 2018;14(2):121-37.
12. 12. Jarczak D, Kluge S, Nierhaus A. Sepsis-Pathophysiology and Therapeutic Concepts. Front Med (Lausanne). 2021;8:628302.
13. 13. Arora J, Mendelson AA, Fox-Robichaud A. Sepsis: network pathophysiology and implications for early diagnosis. Am J Physiol Regul Integr Comp Physiol. 2023;324(5):R613-24.
14. 14. Poll T, Opal SM. Host-pathogen interactions in sepsis. Lancet Infect Dis. 2008;8(1):32-43.
15. 15. Unar A, Bertolino L, Patauner F, Gallo R, Durante-Mangoni E. Pathophysiology of Disseminated Intravascular Coagulation in Sepsis: A Clinically Focused Overview. Cells. 2023;12(17):2120.
16. 16. Kim WY, Hong SB. Sepsis and Acute Respiratory Distress Syndrome: Recent Update. Tuberc Respir Dis (Seoul). 2016;79(2):53-7.
17. 17. Gyawali B, Ramakrishna K, Dhamoon AS. Sepsis: The evolution in definition, pathophysiology, and management. SAGE Open Med. 2019;7:2050312119835043.
18. 18. Singer M, Deutschman CS, Seymour CW, Shankar-Hari M, Annane D, Bauer M, et al T, Vincent JL, Angus DC. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-10.
19. 19. Bein T, Grasso S, Moerer O, Quintel M, Guerin C, Deja M, et al. The standard of care of patients with ARDS: ventilatory settings and rescue therapies for refractory hypoxemia. Intensive Care Med. 2016;42(5):699-711.
20. 20. Getto L, Zeserson E, Breyer M. Vomiting, diarrhea, constipation, and gastroenteritis. Emerg Med Clin North Am. 2011;29(2):211-37.
21. 21. Comstedt P, Storgaard M, Lassen AT. The Systemic Inflammatory Response Syndrome (SIRS) in acutely hospitalised medical patients: a cohort study. Scand J Trauma Resusc Emerg Med. 2009;17:67.
22. 22. Faix JD. Biomarkers of sepsis. Crit Rev Clin Lab Sci. 2013;50(1):23-36.