Question

Case study on Osmosis:

In Habersham County, Tom was feeling slightly nervous as he exited the staff lounge

and entered the hustle and bustle of County Hospital’s ER to begin his first shift as an RN. The first few hours of his shift passed slowly as Tom mostly checked vital signs and listened to patients complain about various aches, pains, coughs, and sniffles. He realized that the attending physician, Dr. Greene, who was rather “old school” in general about how he interacted with nursing staff , wanted to start him out slowly. Tom knew, though, that the paramedics could bring in a trauma patient at any time.

After his lunch break, Tom didn’t have long to wait before the paramedics burst in through the swinging double-doors of the ambulance bay wheeling in a young man on a gurney. Edward, a veteran EMT, recited the vital signs to Tom and Dr. Greene as they helped push the gurney into the trauma room, “A 18-year-old male, GSW to the right abdomen, heart rate 92, respiratory rate 22, blood pressure 95/65 no loss of consciousness.” A gunshot wound! Tom knew that gunshot wounds were sometimes the most difficult traumas to handle.

Once inside the trauma room, Dr. Greene began his initial assessment of the patient while Tom got busy organizing the things he knew would be needed. He attached a pulse-ox monitor to the patient’s index finger so Dr. Greene could keep an eye on the O2 levels in the patient’s blood and he inserted a Foley catheter so the patient’s urine output could be monitored.

After finishing his initial duties, Tom heard Dr. Greene saying, “It looks like the bullet missed the liver and kidney, but it may have severed an artery. That’s probably why his BP is a bit low. Tom, grab a liter of saline and start a fast IV drip … we need to increase his blood volume.” Tom grabbed one of the fluid-filled bags from the nearby shelf, attached a 12-gauge IV needle to the plastic tubing, and gently slipped the needle into

the patient’s antecubital vein. He then hung the plastic bag on the IV stand and let the fluid quickly start to flow down the tubing and into the patient’s vein.

The reaction was quick and violent. The patient’s heart rate began to skyrocket and Tom heard Dr. Greene shouting, “His O2 saturation is falling! Pulse is quickening! What is going on with this guy?!” Tom stood frozen in place by the fear. He heard Dr. Greene continuing, “Flatline! We’ve lost a pulse … Tom, get the crash cart, we need to shock this guy to get his heart going again!” Tom broke free from his initial shock and did as Dr. Greene had ordered. He then started CPR as Dr. Greene readied the cardiac defibrillator to shock the patient. They continued to alternate between CPR and defibrillation for almost an hour, but to no avail. As Dr. Greene announced the time of death, Tom felt a sickening feeling in the pit of his stomach. He couldn’t believe that he had lost his first trauma patient!

Then Tom noticed that the fluid in the Foley catheter bag was bright red. “Dr. Greene, there’s hemoglobin in the Foley bag,” he said. “How could that be?” responded Dr. Greene. Tom began to trace back over his steps in the trauma, trying to think of anything that could have caused the hemoglobinuria. His mounting fear turned to outright terror as he looked at the now empty bag on the IV stand. Its label didn’t read “Saline,” but rather “Distilled Water.” He looked at Dr. Greene, his heart quickly sinking, and said, “I think I may have killed the patient.”

“Osmosis Is Serious Business!” by Troy R. Nash

Questions

What problem did the distilled water in the patient’s bloodstream create?

What happed to the patient’s blood cells as a result?

Considering the function of red blood cells, why did the patient’s oxygen levels fall?

After Tom made his error, is there anything that could have been done to save the patient’s life?

2) The solute concentration in blood is equivalent to 0.9% NaCl.

Several drops of blood were added to three different solutions: 0.09% NaCl, 0.9% NaCl and 9% NaCl. What would happen to the cells dipped in three different solutions?

Answer 1

1. The problem with the distilled water is it is a hypotonic solution which has lower osmotic pressure therefore it causes the blood cells to expand which is not good and it can lead to death.

2. As the distilled water causes the blood cells to expand, an as there is limited space for the blood to flow it can cause the blood cells to break or rupture which will evntually lead to death.

3. The patient oxygen level fell because of the hypotonic solution which caused the blood cells to expand and slowed the movement of blood cells and made the cells rigid and hard, another cause would be loss of blood.