If mechanical capture is not achieved during external pacing, what adjustment should be made first?

• A. Increase rate
• B. Increase the milliamps by 5 mA
• C. Increase energy
• D. Decrease milliamps

Answer: (B)

When external pacing fails to produce a mechanical contraction, the pacing stimulus isn’t strong enough to depolarize enough myocardium. The first step is to increase the output by small amounts, typically about 5 mA, while keeping the rate constant. This step raises the current delivered to the heart, making it more likely to achieve both electrical and mechanical capture without jumping to higher energy settings or changing the rate. If the myocardium still doesn’t respond after this adjustment, you’d then troubleshoot electrode contact/impedance or consider other factors. Decreasing the current would make capture even less likely, and changing the rate isn’t aimed at solving this issue and could cause instability; simply increasing the milliamps in small increments is the safest first action.