Final answer:
If you are unable to aspirate from either CVC limb, first ensure there are no external obstructions, reposition the patient, and ask them to cough. If these steps don't work, inform a healthcare provider as it may indicate a serious issue such as a clot or kink in the catheter.
Step-by-step explanation:
If you are unable to aspirate from either CVC limb, it is important to consider a few steps. Firstly, check for any obvious obstructions and ensure that all clamps are open and the system is properly connected. If there are no external issues, reposition the patient; sometimes lying flat or turning to the left side can help. Also, ask the patient to cough, as this might change the intrathoracic pressure and help with aspiration. If these maneuvers fail, it could indicate a more serious problem such as a blood clot or kinking of the catheter, and you should notify a healthcare provider immediately. The inability to aspirate can prevent medications from being delivered or blood from being drawn, which can compromise patient care.