The next sections will focus on medications related to regulating the autonomic nervous system.  Before we do that, it is important to re-examine the nursing process in guiding the nurse who administers ANS medications.  The nursing process consists of assessment, diagnosis, outcome identification, planning, implementation of interventions, and evaluation.  Because diagnosis, outcome identification, and planning are specifically tailored to the individual client, we will broadly discuss considerations related to assessment, implementation of interventions, and evaluation with medication administration.

Assessment

Recognizing cues…

Recall that assessment is all about recognizing and analyzing “cues” from your conversations and physical assessment of your clients.

Many types of medications stimulate or inhibit specific ANS receptors. By knowing the effects, it becomes easy for the nurse to recognize side effects resulting from the stimulation or inhibition of ANS neuroreceptors. Medications that stimulate ANS receptors often impact the heart, lungs, and blood vessels.

Sympathetic (adrenergic) effects (fight or flight) lead to increased heart rate, bronchodilation, pupil dilation, increased blood sugar, and diaphoresis. As such, nurses must monitor a client’s blood pressure, heart rate, lung sounds etc for expected therapeutic effects and side effects.

Parasympathetic (cholinergic) effects (rest and digest) lead to increased urination, increased peristalsis and diarrhea, bronchoconstriction, bradycardia and hypotension.  As many medications can cause anti-cholinergic effects, the nurse should assess for such effects as urinary retention, constipation, blurred vision, tachycardia and dry mouth.

As part of a comprehensive assessment, obtain a baseline before administering medications.  This includes vital signs to detect bradycardia or hypotension, lung sounds (crackles, wheezes) and GU/GI system (bowel sounds, bowel movements, urine output).

Planning

Next, plan (refine your hypothesis), and take action.

When planning your care, this includes cue recognition and prioritization, refining your hypotheses based on your client assessment.

Common goals include:

• Client will understand the effects of their medication, and the importance of adhering to the medication regimen.
• Client’s vital signs will be within the desired range.

Implementation of Interventions

A nurse should be aware of parameters to administer or withhold medications affecting the autonomic nervous system. If the ordered parameters are unclear, the nurse should withhold the medication following safe administration guidelines and notify the prescriber.  For example, when no parameters are provided, blood pressure medications should not be administered if the client’s apical heart rate is less than 60 beats per minute and/or the systolic blood pressure is less than 100 mmHg. As with all parameters, they are context-dependent and medication specific.  For example, a client who is physically fit may have a resting heart rate of 50 bpm, thereby the 60-bpm guideline would not be appropriate.

Report any marked change in vital signs or suspected adverse effects.

Implement fall precautions, when needed, based on anticipated side effects of ANS medications.

Evaluation

Finally, evaluate the outcomes of your action.

It is always important for nurses to know the reason why a medication is ordered for a specific client, so evaluation of therapeutic effectiveness can be documented. For example, if the purpose of medication is to improve urine flow, then improvement should be seen and documented. Otherwise, the side effects may not warrant the use of the medication.