Final answer:
A hypotonic solution was likely the cause of RBC lysis in the hospital error. Among the options provided, 300 mM urea would be the suspected solution as it can lower the effective osmolarity, leading to water influx into RBCs and hemolysis. Typical isotonic saline is about 150 mM NaCl, which is the correct concentration to prevent such issues.option (a)
Step-by-step explanation:
The infusion of a solution that causes lysis of red blood cells (RBCs) indicates the injected solution was likely hypotonic relative to the blood plasma. RBC hemolysis occurs when an excessive amount of water flows into the cells, causing them to swell and burst. The typical isotonic saline solution that does not cause hemolysis is approximately 0.9% m/v NaCl solution, equivalent to 150 mM NaCl. Given the options, 150 mM NaCl is isotonic and would not cause hemolysis. In contrast, all other solutions listed are either hypertonic or hypotonic, but considering lysis, the most likely culprit would be a hypotonic solution, such as 300 mM urea. Urea can easily pass through RBC membranes, reducing the solution's effective osmolarity, leading to water influx and subsequent cell lysis.
Option 1) 150 mM NaCl is closest to normal saline and is isotonic, therefore it is not the solution that caused the hemolysis. Options 2) and 3) with mannitol are hypertonic and would more likely cause cells to shrink, while 5) 150 mM CaCl₂ is also hypertonic. Therefore, among the provided options, 4) 300 mM urea would be the correct answer. It is important for clinicians to ensure that intravenous drugs are formulated in isotonic solutions to prevent hemolysis or crenation of RBCs.