Pain Management of Common Chief Complaints in the ED

Authors: Nikhil B. Bhana, MD (EM Resident Physician, University of Massachusetts/UMass Chan Medical School); Clarence Kong, MD (Pain Fellow, Eastern Virginia Medical School – Virginia Health Sciences at Old Dominion University); Mani Hashemi, MD (EM Attending, HCA Florida Mercy Hospital); S.M. Jafar Mahmood, MD (Pain Medicine Attending, Paincare Medical Practice) // Reviewed by: Jessica Pelletier, DO, MHPE (EM Attending, APD, University of Missouri-Columbia), Marina Boushra, MD (EM-CCM Attending, Cleveland Clinic); Brit Long, MD (@long_brit)

Introduction:

• Pain management in the ED can be a unique challenge. 
• Most patients presenting to the ED seek care for pain-related complaints.¹
• The ED is a fast-paced environment where patient stability and life-and-limb-threatening conditions are prioritized.
• The American Academy of Emergency Medicine has called effective, efficient, and safe pain management a “specialty-defining skill.”²
• This post discusses stepwise management of the most common painful ED diagnosis, organized by anatomical location. Medication dosages detailed in this article are suggestions; local institutional pharmacy dosage policies should be followed.

1. A 28-year-old female presents to the ED with sharp, left-sided chest pain that started two days ago. The pain is worse with deep breaths, coughing, or certain movements, and improves with rest and nonsteroidal anti-inflammatory drugs (NSAIDs). 
2. A 45-year-old male presents to the ED after a motor vehicle collision where he was the restrained driver. He reports severe, localized chest pain, worsened by breathing, coughing, and movement. He denies shortness of breath or abdominal pain but has difficulty taking deep breaths due to pain.
3. A 32-year-old male presents to the ED with a sharp, central chest pain that has been worsening over the past 3 days. The pain is relieved by sitting forward and worsens when lying flat or taking deep breaths. He reports a recent upper respiratory infection but denies shortness of breath, leg swelling, or recent trauma.

Chest Pain:

• Within the United States, chest pain accounted for nearly 7.6 million patient complaints in 2017, making it the second most common ED complaint.⁵
• In addition to the management of acute pain, it is important to identify if the cause of chest pain is life-threatening (Table 2). 
• Costochondritis, rib fractures, and pericarditis are common causes of chest pain that can be treated with multimodal regimens.

Costochondritis: 

• Costochondritis is inflammation of the sternal articulations and costal cartilages causing chest wall pain that is usually reproducible with palpation.⁶  
  • Clinical course can last weeks to months.
  • Most cases abate by one year. The provider must educate the patient on the anticipated clinical course.⁷

Rib and Sternal Fractures: 

• Rib fractures are often caused by blunt chest trauma. 
• Up to two-thirds of rib fractures are missed on initial chest radiographs.¹⁰ 
• Rib fractures can result in exquisite pain and can cause complications like pneumothorax, pneumonia, atelectasis, and delirium.¹¹  
• Aggressive and timely analgesia is critical to reduce subsequent complications, morbidity, and mortality.^12,13

Pericarditis:

• Pericarditis, inflammation of the pericardium, is known to cause pleuritic chest pain.
• Pain can be associated with a friction rub on cardiac auscultation, a pericardial effusion on a bedside echocardiogram, or diffuse ST elevations on an EKG.¹⁷

1. A 26-year-old female presents to the ED with a throbbing, unilateral headache on the right side that began 12 hours ago. The pain is moderate to severe in intensity, associated with nausea, photophobia, and phonophobia. She reports a history of similar headaches but this one is more prolonged. She denies any recent head trauma, neck stiffness, or vision changes.
2. A 34-year-old male presents to the ED with severe, excruciating pain around his left eye. The pain began abruptly 1 hour ago, described as a stabbing sensation, and has occurred daily at the same time for the past week, each episode lasting about 45 minutes. He also reports associated left-sided nasal congestion, tearing, and ptosis during the attacks. He denies any nausea, photophobia, or aura.
3. A 30-year-old female presents to the ED with a dull, bilateral headache that started 3 days ago. She describes the pain as a tight, band-like pressure around her forehead and temples. The headache is mild to moderate in intensity, without associated nausea, vomiting, photophobia, or phonophobia. She reports increased stress at work but denies any recent trauma or history of migraines.

Headache:

• Headaches account for over 2.1 million ED visits per year (2.2% of visits) and represent the 4th most common chief concern in the ED.¹⁹  
• A variety of etiologies can lead to a patient presenting to the ED with headache. These causes can be divided into two distinct categories: benign and malignant. 
• Red-flag headache characteristics can point to malignant pathology that should warrant further workup (Table 6).
• Headache red-flag characteristics include neurological symptoms, thunderclap nature, syncope, trauma, immunocompromised, coagulopathy, fever, rash, seizure, nuchal rigidity, altered mental status, pregnancy, temporal tenderness, jaw claudication, and cancer history.
• This post focuses on pain management for benign headaches.

Migraines:

• Migraines cause approximately 1.2 million visits to the ED in the United States (US).²⁰  
• Migraines are defined as recurrent headaches lasting 4-72 hours and are often characterized by unilateral, pulsating, moderate to severe pain that is aggravated by physical activity. 
• Frequently associated symptoms include photophobia, phonophobia, nausea, or vomiting.²¹

Cluster Headaches: 

• Cluster headaches are a primary headache disorder affecting up to 0.1% of the population. 
• These headaches occur in “clusters” over days to weeks, at the same time of day, and in the same anatomical location.⁴¹
• Clutter headaches are characterized by severe and unilateral orbital, supraorbital, or temporal pain lasting 15–180 minutes. The headache is usually accompanied by at least one of the following: ipsilateral conjunctival injection, lacrimation, congestion, eyelid edema, facial diaphoresis, miosis, ptosis, restlessness, or agitation. Attacks have a frequency from every other day to eight per day.¹⁹
• Effective treatment includes avoidance of triggers, abortive strategies, and prophylactic medication.

Tension Headache: 

• A primary headache disorder that presents with bilateral non-pulsating pain in a band-like or vice-like distribution around the head. Tension headaches are characterized by bilateral location and mild to moderate intensity. 
• Nausea, vomiting, photophobia, and phonophobia are NOT associated with tension headaches.²¹

1. A 40-year-old male presents to the ED with a burning epigastric pain that has been worsening over the past week. The pain is worse after meals and at night, but improves with antacids. He reports associated bloating and frequent burping but denies nausea, vomiting, or weight loss. He has a history of occasional NSAID use for joint pain.

Abdominal Pain:

• Acute abdominal pain accounts for approximately 7 million ED visits annually (5 to 10% of all ED visits).^48,49
• The abdominal region contains a multitude of critical organs including the liver, spleen, kidneys, pancreas, gallbladder, stomach, bowel, aorta, inferior vena cava, and ovaries. Chest and thoracic pain commonly refer to the abdominal region.⁵⁰
• The differential diagnosis for abdominal pain is broad and diagnoses can be easily missed. In up to 25% of cases, the exact etiology of abdominal pain remains undifferentiated at the time of discharge.⁵¹

Abdominal Pain Clinical Pearls:

• Patients over 65 have a six- to eight-fold increased risk of mortality compared to younger patients when presenting to the ED for abdominal pain.^52,53  Their pain intensity does not correlate with disease severity and pain location does not correlate with disease location. A low threshold to obtain imaging should be maintained in this population. 
• Every patient, assigned female-at-birth (AFAB), of child-bearing age should get a pregnancy test.
• Physicians should ensure the patient can tolerate oral intake before discharge. 
• Treatment pathways for various causes of abdominal pain are similar. Generally, a stepwise approach should be utilized. 
• Both pain and associated nausea should be treated. 
• Abdominal pain and gastritis caused by NSAIDs, alcohol, or marijuana may benefit from cessation of the inciting substance. 

Mild to Moderate Gastric Pain: 

• Common etiologies include gastritis, gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD), and other gastric pain. 
• Pain can be gnawing, aching, burning, and located in the upper abdomen. 
• Pain can be improved or exacerbated with meals.⁵⁴
• It is vital to consider dangerous epigastric pain mimickers like acute coronary syndrome (ACS), hepatobiliary disease, or pancreatitis.⁵²

Moderate to Severe Abdominal Pain: 

• Analgesia has been proven to not interfere with abdominal pain assessment or diagnosis.^53,60
• Moderate to severe abdominal pain should be treated aggressively while the etiology of pain is investigated with labs or imaging. 
• Opioid analgesia is appropriate for moderate to severe acute abdominal pain (Table 1).
• The goal of pain management is not to eliminate pain, but rather to facilitate examination and workup.

1. A 50-year-old male presents to the ED with lower back pain that began after lifting a heavy object 3 days ago. The pain is dull, localized to the lumbar region, and worsens with movement or prolonged sitting. He denies radiating pain, numbness, weakness, or bowel/bladder dysfunction. He has no history of trauma or previous back problems.

Back Pain:

• Back pain is the eighth most common concern in the ED in the US.⁵
• The etiology of acute back pain is often multifactorial. Even after standard pain management, up to one-third of patients will continue to have pain for months.⁶¹
• It is critical to educate patients on outpatient nonpharmacologic treatments as most back pain improves regardless of the pharmacologic treatment used.^62,63 
  • The most recent American College of Physicians Guidelines recommend the following:⁶⁴
    • For acute and subacute low back pain: heat (moderate-quality evidence); and acupuncture, massage, or spinal manipulation (low-quality evidence).
    • For chronic low back pain: acupuncture, exercise, mindfulness-based stress reduction, multidisciplinary rehabilitation (moderate-quality evidence); and cognitive behavioral therapy, electromyography biofeedback, low-level laser therapy, motor control exercise, operant therapy, progressive relaxation, spinal manipulation, tai chi, or yoga (low-quality evidence). 
      • Pharmacologic therapy should only be utilized for chronic low back pain for patients who have not responded adequately to the aforementioned options.
• Managing patient expectations is vital. Patients must understand the likelihood of persistent pain during recovery. 

1. A 35-year-old female presents to the clinic with diffuse muscle aches and joint stiffness, primarily in the shoulders and lower back, that began 1 week ago after starting a new exercise routine. The pain is worse with activity but improves with rest. She denies any trauma, swelling, or redness in the joints, as well as fever or weight loss.

Musculoskeletal Pain:

• Musculoskeletal (MSK) pain is a common painful complaint seen in the ED.⁵  
• Etiologies range from long bone fractures, chest pain, back pain, and soft tissue contusions. 
• The diversity of MSK pain etiologies necessitates a multimodal approach of opioid, non-opioid, and regional analgesics.

1. A 60-year-old male with a history of diabetes presents to the clinic with burning and tingling pain in both feet, which has been progressively worsening over the past several months. The pain is described as a constant, sharp, “pins-and-needles” sensation, particularly at night, affecting his sleep. He denies any recent trauma, weakness, or changes in balance but reports some numbness in his toes.

Neuropathic Pain:

• Neuropathic pain is triggered by lesions to the somatosensory nervous system that alter its structure and function. 
• Pain can be triggered spontaneously and noxious/innocuous stimuli are pathologically amplified.⁸⁰
• It can be caused by traumatic nerve, spinal cord, or brain injury (including stroke) or can be a sequela of conditions like diabetes, HIV/AIDS, postherpetic neuropathies, multiple sclerosis, cancer, or chemotherapies.⁸¹

1. 22-year-old female with a known history of sickle cell disease (SCD) presents to the ED with severe, sharp pain in her chest and back that began suddenly 4 hours ago. She rates the pain as 9/10 and describes it as the worst pain she has ever experienced. She reports feeling fatigued and has had mild fever and chills over the past day.
2. A 28-year-old male presents to the ED with sudden onset, severe right flank pain that began 2 hours ago. He describes the pain as sharp and intermittent, radiating to the groin. He reports associated nausea but denies vomiting, fever, or changes in urinary habits.

Sickle Cell Disease (SCD): 

• Vaso-occlusive pain crises are the most common reason for patients with SCD to present to the ED.⁸⁴
• It is critical to identify life-threatening conditions associated with pain crises (Table 16). 
• Sickle cell pain management has been shown to reduce hospital admissions.⁸⁵
• In addition to pain management, adequate hydration and oxygenation are key to managing a vaso-occlusive pain crisis.⁸⁶
• Clinicians should strongly consider providing SCD patients with incentive spirometers when treating them for pain crises, as this simple and inexpensive intervention can help reduce the risk for acute chest syndrome.⁸⁷
• Following the patient’s individualized care plan (where available) is essential.

Renal Colic Pain: 

• Renal colic pain constitutes approximately 2 million annual ED visits and approximately 1 in 10 people experience this condition.⁹⁰ 
• Renal colic pain is painful and prompt pain management can reduce associated nausea and vomiting. 
• Pain is hypothesized to be prostaglandin-mediated and thus NSAIDs are the mainstay treatment.⁹¹

Pearls and Pitfalls:

• Management of pain in the ED begins with a thorough assessment to rule out life-threatening conditions.
• Identifying the specific type of pain is crucial, allowing for targeted treatments.
• A comprehensive, patient-centered approach to pain management ensures effective treatment across these diverse pain syndromes, ultimately improving patient outcomes.

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