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Management of the patient with abdominal pain begins with attention to the patient’s airway, ventilation, and hemodynamic stability. Patients in profound shock may benefit from a secure airway and positive‐pressure ventilation. Vascular access is indicated in some abdominal pain patients for fluid and medication administration. If the patient has experienced significant fluid loss or has evidence of shock, two large bore IVs should be established. If IV access is difficult or unobtainable, intraosseous access may be indicated. Resuscitation with crystalloid solution (normal saline or Ringer’s lactate) is generally indicated for prehospital hemodynamic instability. The increasing availability of blood products in the out‐of‐hospital environment is enabling their administration for nontraumatic indications such as massive gastrointestinal hemorrhage or aneurysmal rupture. However, evidence‐based indications and outcome data are lacking [4, 5]. Vasopressors such as norepinephrine may be indicated if septic shock from an abdominal source is suspected and the mean arterial pressure is below 65 mmHg despite adequate volume resuscitation. While such medications are often not available to prehospital EMS personnel, they may be available to EMS physicians or to personnel providing an interfacility transport for more advanced care. Any patient with hemodynamic compromise should have continuous cardiac monitoring; the same may be true for all patients over 50 years of age, though again, evidence is lacking. A 12‐lead ECG should be obtained and interpreted to rule out acute myocardial infarction in patients with cardiac risk factors such as age, diabetes, or hypertension. Continuous pulse oximetry should be used in critically ill patients or those with suspected pulmonary etiologies. Supplemental oxygen should be administered to patients with respiratory distress or hypoxia.

There are reports describing the use of ultrasound in the prehospital setting. New ultrasound technology is lightweight, provides high‐quality resolution, and can withstand a wider range of environmental conditions. Some paramedics have been trained in the focused assessment with sonography in trauma (FAST) exam as well as abdominal aortic ultrasound to evaluate for aneurysm. Multiple studies have shown that under close physician supervision, the point‐of‐care FAST exam and abdominal aorta ultrasound are feasible and useful in the prehospital setting [6–8]. They can provide earlier information regarding the patient’s condition, leading to more informed triage decisions, reduced time to diagnosis, and improved delivery to definitive care (see Chapter 69).

Several studies have evaluated prehospital lactic acid measurement in nontrauma patients. There may be potential benefit for undifferentiated patients with abdominal pain. Elevation in prehospital lactate has been linked to mortality and may provide information superior to that of the patient’s vital signs in detecting occult shock, as well as facilitating resuscitation at an earlier stage in patient care [9–11].

Historically, there have been eloquent expressions of concern regarding analgesic administration to not‐yet‐diagnosed patients with abdominal pain [12–15]. The general foundation for reluctance to pursue pain relief is belief that pain provides an important diagnostic clue, and any attenuation could lead to delayed or missed diagnosis of important pathology. Proponents of treating abdominal pain with analgesics stress that a more comfortable patient is better able to participate in a reliable physical examination, and diagnostic tools and accuracy have improved greatly since concerns were articulated. They further point out that adverse outcomes related to diagnostic efficiency are not directly associated with analgesic administration [15–20]. Thus, the goal for EMS has generally evolved. Pain should be treated to the extent that it facilitates a detailed history and physical exam from a patient who is alert and able to cooperate. Opioids have been the mainstay of pain management. However, other agents may also provide value in specific circumstances and, barring general contraindications, include nonsteroidal anti‐inflammatory drugs (e.g., ketorolac), acetaminophen, and nondissociative doses of ketamine [21].

With regard to resuscitating patients with abdominal pain and suspected or known intra‐abdominal hemorrhage, such as ruptured aortic aneurysm or ruptured ectopic pregnancy, attempts to restore normotensive states may not be possible in the prehospital environment. In fact, it may be harmful. These conclusions are drawn from animal and clinical studies of hemorrhagic shock that demonstrate that some level of “permissive hypotension” may improve outcomes [22–24]. Animal research showed no differences in organ perfusion, cardiac output, and lactic acid levels between permissive hypotension and normotensive resuscitation groups. It defined permissive hypotension as 60% of baseline mean arterial pressure [25].

Urinary catheters serve as both a management tool and source of some abdominal pain. Their presence and functionality should be noted during patient examination. Patients with both indwelling urethral and suprapubic catheters are at risk for urinary tract infections, mechanical obstruction, or catheter displacement. EMS clinicians may be trained to place urinary catheters, observing sterile technique, to relieve bladder distention. They should be educated that patients with recent urethral procedures or bleeding from the urethral meatus should not be catheterized due to risk of urethral injury.