Treat perfusion, pain, and nausea while screening for cardiac or aortic emergencies.
OCEMS source summary · Updated 2026-09-16
Key cautions & base contact
Known or suspected pregnancy excludes the source’s ondansetron branch.
Do not miss a cardiac or vascular cause while treating pain and vomiting.
Initial assessment
Maintain the airway and suction when needed. Assess onset, location/radiation, associated vomiting, pregnancy possibility, vital signs, and perfusion.
Upper abdominal discomfort may be an anginal equivalent; consider a 12-lead with cardiac history or suspected cardiac origin.
Perfusion and nausea
For dehydration or poor perfusion with clear lungs/no CHF, give normal saline 250 mL IV and reassess; repeat to a maximum 1 L as needed for perfusion.
For nausea/vomiting when pregnancy is neither known nor suspected, the source lists ondansetron 8 mg ODT OR 4 mg IV, with one repeat 4 mg IV dose after approximately 3 minutes for recurrent symptoms.
Severe pain
With systolic BP above 90, morphine is 5 mg (or 4 mg carpuject) IV/IM, with one repeat after 3 minutes as needed. Alternative fentanyl is 50 mcg IV/IM or 100 mcg IN, with one repeat after 3 minutes.
Choose the applicable pathway, count prior doses, and reassess BP, respiratory effort, oxygenation, mental status, and pain.
Aortic concern and destination
Sudden abdominal/back/flank pain with shock or abnormal pulse rate can suggest AAA disruption. A pulsatile mass or lost distal pulses may be absent.
Risk factors in the source include age above 50, male sex, hypertension, known/family AAA, or vascular disease. Contact base for suspected AAA and possible trauma-center triage.
Otherwise transport to the nearest ERC, with ALS escort when medication or saline is given, or obtain base direction as needed.