A Typical Night in the ER
The ambulance call comes in.
"We're running lights and siren with a 67 year old male. He's confused, lethargic, blood pressure 80 over 40, thready pulse (a pulse that is very fine and barely perceptible) and sweaty. We'll be at your door in a couple of minutes."
The nurses start setting up the equipment to care for the patient. We've been through this drill before when someone arrives at the ER with low blood pressure. I hope it's an easy diagnosis and something that we can treat quickly. IV's are set up, monitor pads ready. The respiratory tech arrives with her machines just in case they are needed.
The EMTS unload a man in obvious distress, sweaty, struggling to breathe, and limp.
The diagnosis could be easy, but there are a variety of factors that could be causing this man's condition. He is in shock; his blood pressure is so low there is not enough pressure to provide blood flow and oxygen to his brain. That's why he is lethargic. No doubt the rest of his organs are at risk too. But why?
The patient's vital signs are poor. His blood pressure has fallen to a little to 70 over 40, his heart rate is 130, and he's breathing over 30 times per minute. Temperature is 103 F. All bad, but all pointing to an infection and perhaps easily fixed with some IV fluids.
He's struggling to breathe but is awake enough to complain that his chest hurts to breathe. His right lung sounds like there's a pneumonia or infection. But he's also wheezing heavily in both lungs. What else could it be? A pulmonary embolism (blood clot to the lung) could cause shock and fever. Tuck that thought away in case it's needed.
The nurses are already in motion, and two IVs have been placed. Fluid is being pumped in. Lab tests and a chest X-ray have been ordered.
No time to wait for test results. The patient needs help now. The respiratory tech sets up a BiPAP machine to help support his breathing. It pushes air into the mouth and lungs to try to force air into the lungs. Medication is added to relieve the wheezing. There is a downside to BiPAP. It can lower the blood pressure for a while as the body gets used to it, but the alternative is to intubate this patient and put him on a ventilator.
The patient has a history of smoking and COPD; putting him on a ventilator increases his mortality (risk of death) significantly. He has to hold on, so that the medical procedures and tests we are doing can reverse his illness and to raise his blood pressure.
The chest X-ray confirms the diagnosis of pneumonia. Say goodbye to the diagnosis of pulmonary embolism. Antibiotics are given. The intravenous fluid infusion hasn't increased the blood pressure yet, but it's still early. He's tolerating the BiPAP machine, not an easy feat, since it feels like sticking your head outside a car window as you go down the road at 50mph.
The good news is that he's waking up a little bit. While the blood pressure is low, perhaps the fluid is allowing more oxygen delivery to the brain.
Two liters of fluid have been run in; 4.4 pounds - the same amount as a large bottle of soda. The blood pressure refuses to move higher, and more needs to be done. You're not supposed to treat a number, since the clinical picture is more important than getting the patient to look good on paper. Still, a systolic blood pressure of 70 is too low and it may mean that the organs in the body are lacking sufficient blood flow and oxygen to maintain aerobic metabolism. If he goes anaerobic (lack of oxygen) for a prolonged period of time, then the acid-base balance in the blood stream will cause everything to spiral downhill and the battle will be lost.