Based on Rebecca’s initial presentation and vital signs, it should be clear that her body is working, perhaps even struggling, to maintain homeostasis. With no pertinent medical history, a normal — or slightly low — blood pressure and rapid heart rate, in conjunction with complaints of dizziness when standing and general lethargy, orthostatic vital signs may be a beneficial assessment tool. Care should be taken, however, in a patient already reporting dizziness when standing to prevent a syncope or fall when testing for orthostatic vital signs.
Rebecca’s history of abdominal pain is consistent with a ruptured appendix and appendicitis. The hallmark of this condition is worsening abdominal pain, which increases until the appendix ruptures. The patient may experience some pain relief and assume that her condition has resolved. Pain returns, however, when an infection in the abdomen results in peritonitis or inflammation of the lining of the organs and abdominal cavity. This infection can spread and may become life-threatening.
Systemic Inflammatory Response Syndrome
Systemic Inflammatory Response Syndrome is the term used to identify inflammation present throughout the body. SIRS is not necessarily linked to one particular pathophysiologic process, but rather is simply the extension of inflammation which occurs when the local insult from infection or trauma continues unchecked and results in the involvement of the entire body. Though historically associated with sepsis, SIRS may be present after traumatic injury.
Screening for SIRS is relatively simple and most assessments are in the scope of EMS providers. For a patient to qualify as having SIRS, two of following criteria must be true [1]:
- Temperature of >38°C (100.4°F) or <36°C (96.8°F)
- Heart rate >90/min
- Respiratory rate >20/min
- PaCO2 < 32 mm Hg
- White cell count >12,000/mm3
The original paper identifying SIRS —and its link to sepsis —is from 1992. Many hospitals and EMS agencies use the SIRS criteria as an indication that a patient’s infection has become severe enough to result in system-wide inflammation. Essentially, SIRS screening in the presence of a source of known or suspected infection has been used to include a patient in the treatment regimen for sepsis.
Interestingly, several critical care journals have reported that SIRS criteria may simply represent the normal course of the body’s immune response to an infection (increased temperature and heart rate among others) and may not necessarily be associated with organ dysfunction from an out-of-control infection (sepsis) [2]. As a result, SIRS may be too broad an inclusion criteria and not specific enough to determine if a patient has sepsis.
Sepsis
Sepsis is a syndrome — or collection of symptoms associated with a disease — that is caused by infection [2]. It is essentially an amplified, inappropriate response by the body to an infection and can result in significant organ dysfunction. The concern about using SIRS as an inclusion criteria for sepsis is two-fold: First, systemic inflammation may occur as a normal response to an infection and may not be associated with organ dysfunction and failure (sepsis). Second, sepsis can affect multiple pathways in the body and may not always result in systemic inflammation captured by SIRS.
While the usefulness of SIRS may be in question, it is still the standard initial screening tool for sepsis used by many EMS agencies. Refer to your local protocols or medical director for specific guidance on sepsis screening.
The task force convened by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine questioned the usefulness of SIRS in sepsis screening and recommended a sepsis-specific screening tool that evaluates the extent of organ dysfunction in the body called the Sequential [Sepsis-Related] Organ Failure Assessment Score (SOFA) [2]. Unfortunately for EMS providers, however, many of the screening elements used in SOFA require lab results and are out of scope for EMS providers. This recommendation places into question the ability of EMS providers to screen for sepsis which requires aggressive, timely treatment to reduce morbidity and mortality.
One additional screening tool, quick SOFA (qSOFA), has been found to have similar predictive power for poor patient outcome as the full SOFA screening. The qSOFA, which can be assessed in the prehospital setting, is positive when any two of three elements are true:
- Respiratory rate ≥22/min
- Altered mentation (GCS ≤13)
- Systolic blood pressure ≤100 mm Hg
Once a potential source of infection is identified and before aggressive intervention to treat hypotension the qSOFA may be a more effective predictor of mortality from sepsis than SIRS for EMS providers [2].
Goals for treatment
Regardless of how sepsis is screened for, treatment recommendations center on ensuring adequate fluid resuscitation to help maintain organ function. Additionally, patients require blood cultures to be drawn and broad-spectrum antibiotics to be started until a pathogen-specific treatment plan is developed. ALS EMS providers should consult their local protocols and may be asked to draw labs or start fluid resuscitation.
Case conclusion
Though all signs point to appendicitis and sepsis, a thoughtful clinician casts a wide net and considers other problems. In the initial scenario you were asked if you might consider an alternative diagnosis if Rebecca was 24- or 64-years -old. EMS providers should bear in mind that pregnancy, specifically ectopic pregnancy, should be considered as a possibility for any woman of child-bearing age, regardless of whether or not she is taking birth control medication. Even at 44-years-old, Rebecca is still in a high-risk category. If Rebecca were 64-years-old an EMS clinician may consider a bowel obstruction, which can be dangerous in older patients, or ischemia of the lining of the abdominal cavity and organs. Just as differential diagnoses change with assessment findings, they must also change based on a patient’s age and any other recognizable factors which influence the function of body systems.
Following a positive SIRS screening based on Rebecca’s vital signs and a possible history of a ruptured appendix, you call ahead to the responding ALS unit to provide an update. The ALS unit arrives and the paramedic places an IV following her initial assessment. The paramedic uses the newly-approved qSOFA screening tool and agrees that Rebecca likely has sepsis. The patient is transported to the emergency department where she is started on antibiotics before going to surgery. She is expected to make a full recovery.
For more information, check out SurvivingSepsis.org.
References
- Bone, R., Balk, R., Cerra, F., & et al. (1992). American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference: definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. Crit Care Med, 20(6), 864–74.
- Singer, M., Deutschman, C., Seymour, C., & et al. (2016). The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) .JAMA, 315(8), 801–810.
