Diagnostic Workups

Chest pain, shortness of breath, abdominal pain, ALOC, syncope and the sepsis workup: what gets ordered and why.

Diagnostic Workups: Common Complaints

Providers will make a list of the possible diagnoses of the patient's chief complaint (the differential diagnoses) including the most life-threatening conditions. The ER's job is to take care of emergencies so the providers will go down the list of the potential causes to ensure life-threatening and time-sensitive issues are detected and treated. The goal is to rule out the deadly things first. We as nurses are also on the lookout for these deadly conditions, especially in triage. We assess patients who present unstable so they can be prioritized and evaluated by a provider faster. For example, patients with unstable vital signs, altered level of consciousness, visible respiratory distress, pale mottled or cyanotic skin color, diaphoretic, vomiting and so forth. The depth of the workup ordered will depend on how the patient presents, their vitals, the history and physical exam, and risk factors such as age and known medical problems. Our role as the ER Nurse is to carry out these orders proficiently and in a timely manner. We will administer medications, coordinate with radiology (X-ray, CT, US), and send off lab work. We will continually assess and monitor, communicating promptly when needed.

Chest Pain

Chest pain is a very common chief complaint in the ER. Among the deadly conditions of the differential diagnoses include Acute Coronary Syndromes (STEMI, NSTEMI, UNSTABLE ANGINA), CHF Exacerbation, Pulmonary Embolism, unstable ECG rhythms, pneumo's, dissections, valvular stenosis, pericarditis and asthma/COPD exacerbations. The workup can include an ECG, Labs, Chest X-rays, ultrasounds, and CT scans. • ECG: Obtained within 10-15 minutes of the patient arriving as it can help identify signs of ischemia and ACS, as well as dangerous arrhythmias • Labs: Can include Troponins, BNP, and a D-Dimer. A Basic Metabolic Panel (BMP) and a Complete Blood Count (CBC) are usually obtained as well. Troponin helps identify heart muscle damage, the BNP helps with identifying heart failure, and D-Dimer can help with identifying Pulmonary Embolisms. • Chest X-ray: Helps look for pulmonary issues like pneumonia, pneumothorax and pleural effusions. Can also detect cardiomegaly. • Echocardiogram: Helps assess how well the heart is pumping (Ejection Fraction), valves, and heart muscle issues. • CT Scans: Provide more detail of organ structures and vessels, for example to rule out a Pulmonary Embolism.

Shortness of Breath

Among the deadly conditions of the differential diagnoses include Pneumothorax, Pulmonary Embolism, Asthma and COPD exacerbations, Pneumonia, CHF, Anemia, Anaphylaxis and ACS. The workup can include Chest X-rays, ECG, Labs, ultrasounds, and CT scans. • Chest Xray: Helps look for pulmonary issues like pneumonia, pneumothorax, pulmonary edema and pleural effusions. Can also detect cardiomegaly. • ECG: Obtained within 10-15 minutes of the patient arriving as it can help identify signs of ischemia and ACS, as well as dangerous arrhythmias • Labs: D-Dimer, BNP, Troponins, ABG, CBC, BMP o ABG: Helps assess oxygenation, ventilation, and acid-base status o D-Dimer: Assess for Pulmonary Embolism. Often if positive (>500) a CT chest angiogram will be ordered to confirm PE • CT: A Chest Angiogram may be ordered if pulmonary embolism is suspected. As well if more detail of organ structures is needed, for example, if something questionable was seen on the x-ray, the radiologist who read the chest x-ray will write "Recommend CT for further evaluation." • Echocardiogram: Helps assess how well the heart is pumping (Ejection Fraction), valves, and heart muscle issues.

Abdominal Pain

Among the deadly conditions of the differential diagnoses include Aortic Dissection, GI Bleeding, perforated bowel, appendicitis, pancreatitis, cholecystitis, ectopic pregnancy and ruptured ovarian cyst. There are also countless other conditions that should be considered like UTIs, kidney stones, bowel obstructions and even gastritis. The workup may include lab work, Ultrasounds, CT, and ECG. • Labs: Pregnancy Test, Lipase and Amylase, LFTs, Urinalysis, CBC, BMP o Preg Test: Assess for pregnancy and to rule out related issues like ectopic pregnancy o Lipase/Amylase: Evaluate pancreas o LFT's: Evaluate Liver and Gall Bladder o Urinalysis: Assess for UTI, DKA, and kidney function • Ultrasound: Assess for cholecystitis, appendicitis, ectopic pregnancies and intra-abdominal issues • CT: Will help provide more detailed information for possible pathologies in the abdomen • ECG: To help rule out ACS with Atypical Presentations

Altered Level of Consciousness

Among the deadly conditions of the differential diagnoses include stroke (hemorrhagic and ischemic), hypoglycemia, hypertensive encephalopathy, hypoxia, hypercapnia, hepatic encephalopathy, electrolyte issues (hyponatremia), sepsis, seizures and toxic ingestions. There is a useful mnemonic of issues to keep in mind with ALOC, AEIOU TIPS. • A: Alcohol and Arrhythmias • E: Electrolytes and Epilepsy • I: Insulin • O: Overdose and Oxygen • U: Uremia • T: Trauma and Temperature • I: Infection • P: Poison and Psych • S: Stroke The workup may include lab work, x-ray, CT, ECG and EEG. • Labs o Point-of-Care Glucose: Assesses for hypoglycemia or hyperglycemia o Urine Drug Screen and Serum Toxicology: Assesses for overdose (OD) of a substance o Troponin: Assesses for ACS o CBC, BMP: Assesses electrolytes, Infection, Kidney Function, Hgb o If indicated: ▪ Ammonia: Liver Failure ▪ CSF (Will need lumbar puncture): Infection in Spinal Fluid ▪ Coagulation: Assesses for bleeding disorders that increase risk of bleeding (Head bleeds) ▪ VBG: Assesses lactate level and approximate estimate of other values like CO2 ▪ BNP: Assesses for heart failure • Chest X-ray: Hypoxia can cause ALOC. A chest x-ray can help assess for pulmonary conditions contributing to the ALOC such as pneumonia, pulmonary edema, pneumothorax and so forth. • ECG: Can help assess issues that may be affecting perfusion such as arrhythmias and ACS • CT: Helps assess for abnormalities within the brain like brain bleeds and even tumors • EEG: Can help assess for seizures ALOC can have many causes, and when patients also present unstable, the workup ordered can be rather extensive.

Syncope

Among the deadly conditions of the differential diagnoses include arrhythmias, heart failure, ACS, seizures, strokes, brain bleeds, hypoglycemia, hyperkalemia and toxins. The workup can include lab work, ECG, Echocardiogram, chest x-ray, and CT. • Labs o Point of Care Glucose: Assess for hypoglycemia o Troponin: Assess for ACS and heart muscle damage o BNP: Assess for CHF if indicated o CBC, BMP: Assess electrolytes, Infection, Kidney Function, Hgb o Coags: Assess for bleeding disorders that increase risk of bleeding (Head bleeds) o Urine Drug Screen and Serum Toxicology: Assess for overdose (OD) of a substance • ECG: Can help assess issues that may be affecting perfusion such as arrhythmias and ACS • Echocardiogram: If cardiac issues suspected. Helps assess how well the heart is pumping (Ejection Fraction), valves, and heart muscle issues. • Chest Xray: Hypoxia and ventilation issues can potentially cause Syncope. A chest x-ray can help assess for pulmonary and cardiac conditions contributing to the syncope such as pneumonia, pulmonary edema, pneumothorax and cardiac enlargement. • CT: A head Ct can help assess intracranial issues like a head bleed that may have caused Syncope. As you can see, there are many similarities in the workups. The depth of the workup ordered will depend on how the patient presents, chief complaint, their vitals, the history and physical exam and risk factors such as age and known medical problems.

Sepsis Workup

Sepsis is characterized by an infection and the body's unregulated reaction to the infection. What makes sepsis deadly is that it can eventually lead to multi-organ dysfunction and death. The purpose of the sepsis workup is to locate the infection and figure out how sick the patient is. For example, is the patient already in organ dysfunction? Or are they still early in the process. This is important to determine as it gives a sense of the patient's prognosis and determines how aggressive the team needs to be with interventions.

SIRS Criteria

Although I understand that guidelines are changing, many organizations still use SIRS criteria. As we know, sepsis is characterized by an infection, or a suspected infection and an unregulated immune response or again, in other words, SIRS. So when a patient comes into the ER, and you suspect the patient has an infection, you also need to go over the SIRS criteria to help assess whether the patient is septic and ultimately ensure they are placed as a priority. SIRS criteria has four components, three of which you can use in triage. They include a temperature greater than 100.4 F or less than 96.8F, a heart rate greater than 90, a respiratory rate greater than 20, and finally a WBC greater than 12,000 or less than 4,000.

Infection Symptoms

Symptoms that may indicate an infection can include fever, tachycardia, tachypnea, hypotension, fevers, chills and so forth. Again, these do not automatically mean that the patient has an infection, however, they can help guide the evaluation of the patient. For example, if the patient is febrile, tachycardic, has abdominal pain and green stools, it can help point the team in the right direction regarding the workup. Key Point: Keep in mind that the most likely source of infection for septic patients is from the lungs, abdomen and urinary system.

Laboratory Studies for Infections/Sepsis

• CBC: The cbc with a differential will let us know the white count, what type of white blood cells are elevated and whether a shift is present. • CMP: The CMP will let us assess for organ dysfunction and derangements as a result of the infection and the body's response. • Urinalysis: The urinalysis will allow us to see if there is an infection in the urine and the urine culture will help us figure out which antibiotic is most effective. • Blood Cultures: The blood cultures will help us detect whether bacteria is present in the bloodstream and figure out which antibiotic is most effective. The same principle applies if you obtain a culture from a different source, whether it is sputum, a wound or even from any type of tube or drain coming from the patient. • Lactate: The lactate gives us an understanding of the patient's perfusion status, whether tissues throughout the body are getting the oxygen and blood perfusion they need. Typically, the higher the lactate, the higher the mortality rate is. It's also useful to trend it, meaning you get a repeat lactate after initial interventions like fluids to gauge whether they are working. • Lumbar Puncture: The LP will help us assess for an infection in the CSF if the patient is showing meningeal signs or even to rule out when the rest of the work up is inconclusive. • Other: The team may also start ordering additional lab tests like inflammatory markers and a DIC panel. Inflammatory markers like procalcitonin help determine the level of inflammation throughout the body, the higher the level the higher the inflammation. The DIC panel will let us know if clotting factors are being consumed throughout the body, and signal whether they have to be replaced. Source: The main thing I want you to remember is source control. Finding the source of the infection is crucial, especially when we keep trying everything and the patient is showing no signs of improvement. We need to address the source. The worst outcomes that I've seen are when we are unable to find the source. So is it coming from a skin infection somewhere? From the foley? The central line? The PICC line? The nephrostomy tube? The dialysis catheter? (Remember: Chest, Abdomen, Pelvis)

Radiology

The chest x-ray will help us figure out if the patient has pneumonia or any other condition that may be causing the patients' symptoms. The same goes for the CT, it'll help us find the source or perhaps help find the cause for the patient's symptoms.

Treatment

• Antibiotics: As soon as the diagnosis is made, or even when there is a high suspicion of an infection being present, antibiotics need to be administered. Start off with broad spectrum then more targeted towards the potential source, then when the results of the cultures come back, the antibiotics will be specific towards the offending agent. From my understanding, the faster antibiotics are given, the better the outcomes. • IV Fluids: Fluids should be administered, especially when hypotensive, tachy and with a high lactate. Typically NS and LR are preferred. Usually initially it is 30ml per kg in adults. Remember to adjust the dosing when patients have congestive heart failure. • Vasopressors: If fluids do not help with the hypotension, vasopressors will be considered. The first-line vasopressor for sepsis is norepinephrine, then most likely vasopressin. • Supportive: You will also be managing any derangements and abnormalities as a result of the sepsis such as electrolyte issues and organ dysfunction. • Other: The team may consider glucocorticoids when the fluids and pressors do not help with improving perfusion as they are thought to help with adrenal insufficiency when the patient is very critically ill.

Sepsis and Nursing Tips

• Remember to keep in mind the SIRS criteria when triaging patients with a suspected source of infection. • Obtain blood cultures prior to giving antibiotics. • Your facility may employ specific time bundles such as obtaining blood cultures, lactate, giving fluids and antibiotics in a certain time frame from patient arrival, so ensure you become familiar with your organization's protocols. These bundles are to ensure there is no delay in the treatment of septic patients. • Remember that norepinephrine is the typical first-line agent in sepsis, and that it can go peripherally initially. If you do use it peripherally ensure you place a large bore IV in the AC. • Closely monitor your patient to ensure interventions are working and if not, that you are timely communicating with the team.

Updated 30 Aug 2026