block

This lack of flow is called exit block and sometimes this means patients are waiting outside the department in an ambulance.

He said: "Studies have shown that exit block leads to increased mortality.

* Depression of conduction: manifested as AV block or sinoatrial node exit block. First-degree AV block and Mobitz type I 2nd-degree AV block are common manifestations.

Healthwatch chief Anna Bradley said: "This is further evidence of a system that is under growing pressure and struggling to cope." And British Medical Association chief Dr Mark Porter added: "A shortage of social care beds creates 'exit block' in hospitals, meaning patients can't be discharged.

The Queue and FIFO blocks represent in this case the range of information waiting to be processed, which is then processed in the Exit block. The railway crossing is simulated upon the same principle.

The origin of SA exit block commonly occurs in the tissue surrounding the sinus node (the "perinodal" area), which fails to conduct the sinus node (SN) impulse to the rest of the right atrium (RA) (Figure 2).

"However, insufficient resources to match patient numbers all year round has resulted in compromised patient safety, declining four-hour performance, A&E crowding and 'exit block' across Wales."