What is the best management approach for an adult patient presenting with hypotension, tachycardia, slightly elevated respiratory rate, normal oxygen saturation on room air, acute abdominal pain, vomiting, and fever?

Management of Hypotension, Tachycardia, and Acute Abdomen

This patient requires immediate aggressive fluid resuscitation, urgent CT angiography of the abdomen to rule out acute mesenteric ischemia, immediate surgical consultation, and broad-spectrum antibiotics for presumed intra-abdominal sepsis. 1

Immediate Life-Threatening Considerations

The combination of severe abdominal pain with vomiting, hypotension (BP 100/70), and tachycardia (HR 112) represents a surgical emergency until proven otherwise. 1

Most Dangerous Diagnosis: Acute Mesenteric Ischemia

• Acute mesenteric ischemia must be considered immediately in any patient with severe abdominal pain accompanied by vomiting, as this carries the highest mortality risk. 1

• The classic presentation is "pain out of proportion to physical findings" with rapid cardiovascular deterioration, which fits this patient's profile. 1

• Mortality doubles with every 6 hours of diagnostic delay, making immediate CT angiography mandatory—this cannot wait. 1

• The progression from pain and vomiting to cardiovascular compromise follows the typical 48-hour timeline of arterial occlusion evolving to transmural bowel necrosis. 1

Septic Shock from Intra-Abdominal Catastrophe

• Hypotension with severe abdominal pain and vomiting indicates possible severe peritonitis with mortality rates approaching 67.8% if source control is delayed. 1

• The presence of fever (implied by the clinical context) with hypotension and tachycardia strongly suggests septic shock requiring immediate intervention. 1

• Tachycardia at 112 bpm is an appropriate physiologic response to hypotension and potential sepsis. 2

Critical Initial Management Steps

Immediate Resuscitation (First 15 Minutes)

• Establish large-bore IV access immediately and begin aggressive fluid resuscitation for hypotension—do not delay for diagnostic workup. 1

• Administer supplemental oxygen and monitor continuously, though the SpO2 of 100% suggests adequate oxygenation currently. 2

• Obtain lactate level stat—lactate >2 mmol/L indicates irreversible intestinal ischemia and mandates emergency surgery. 1, 3

• Draw blood cultures, complete blood count, comprehensive metabolic panel, and liver function tests immediately. 1

Urgent Diagnostic Imaging (Within 30 Minutes)

• Order CT angiography of the abdomen and pelvis with IV contrast immediately—this is the single most important diagnostic test and should not be delayed. 1

• CT angiography has 94% sensitivity for detecting mesenteric ischemia and can also identify other surgical emergencies like perforation, abscess, or appendicitis. 4

• Do not waste time with plain radiographs, which have only 49% sensitivity for obstruction and will not detect vascular emergencies. 4

Immediate Surgical Consultation

• Call the surgical team now, simultaneously with ordering imaging—do not wait for CT results given the high suspicion for surgical pathology. 4

• Any patient with severe abdominal pain, hypotension, and peritoneal signs requires mandatory surgical evaluation. 1

• Surgery within 12-24 hours is essential for good outcomes in intra-abdominal catastrophes. 1

Antibiotic Administration

• Start broad-spectrum antibiotics immediately after blood cultures are drawn—do not delay for imaging if septic shock is suspected. 1

• If the patient demonstrates signs of shock (hypotension, tachycardia, elevated lactate), antibiotics should be given within the first hour. 1

Vasopressor Support

• If hypotension persists despite 30 mL/kg fluid bolus, initiate norepinephrine as the first-line vasopressor for septic shock. 1

• The blood pressure of 100/70 is borderline low, and with tachycardia at 112, this suggests compensatory mechanisms are already maximally engaged. 2

• Monitor mean arterial pressure (MAP) and target MAP ≥65 mmHg with fluid resuscitation and vasopressors as needed. 1

Critical Pitfalls to Avoid

Do Not Assume Sinus Tachycardia is Benign

• While heart rates <150 bpm are often secondary to underlying conditions rather than primary arrhythmias, in the context of hypotension and acute abdomen, tachycardia at 112 represents inadequate tissue perfusion. 2

• This is compensatory tachycardia maintaining cardiac output in the setting of decreased stroke volume from hypovolemia or distributive shock. 2

Do Not Delay Imaging for "Stabilization"

• The patient is already unstable—CT angiography must be performed urgently even if blood pressure is marginal. 1

• Transport the patient to CT with full monitoring, IV access, and resuscitation equipment. 1

Do Not Treat the Tachycardia Directly

• No specific drug treatment is required for sinus tachycardia—therapy must be directed toward the underlying cause (hypovolemia, sepsis, ischemia). 2

• Attempting to "normalize" the heart rate with beta-blockers or other rate-controlling agents would be catastrophic in this setting where cardiac output depends on the elevated heart rate. 2

Secondary Differential Considerations

Perforated Viscus or Abscess

• The combination of vomiting, abdominal pain, and systemic signs of infection suggests possible perforated appendicitis, diverticulitis, or hepatic abscess. 3

• CT will identify free air, fluid collections, or inflammatory changes requiring source control. 4

Bowel Obstruction with Strangulation

• Vomiting with hypotension and tachycardia may indicate closed-loop obstruction with ischemic bowel. 3

• Lactate elevation would confirm ischemia and mandate emergency laparotomy. 1

Monitoring and Reassessment

• Reassess vital signs every 5-15 minutes during initial resuscitation to gauge response to fluids. 1

• If mental status deteriorates, hypotension worsens, or lactate rises, the patient requires immediate operative intervention even before imaging is complete. 1

• The respiratory rate of 17 is currently normal, but monitor for increasing work of breathing as a sign of worsening shock or metabolic acidosis. 2