BANISH THE BASIN Pre-op screening and preventive practices will do away with one of surgery's most unpleasant complications.

If pain tops the list of sensations patients don't want to feel following surgery, post-operative nausea and vomiting is a close second. Recent enhancements to our pre-op screening protocols and targeted prophylaxis resulted in a 41% decrease in the incidence of PONV. Of the 1,139 adult patients who arrived in PACU after we'd begun administering the new interventions, only 144 (12.6%) felt sick. Take it from us: The key to staving off PONV is a multimodal approach using preventative measures based on a patient's level of risk.

Measure and intervene
Studies have shown that if a surgical patient population goes untreated, about 30% of the patients will suffer PONV. Without prophylaxis, a patient's risk of experiencing the complication is as follows (in rounded figures):

• no risk factors: 10%
• 1 risk factor: 20%
• 2 risk factors: 40%
• 3 risk factors: 60%
• 4 risk factors: 80%

Intervention is clearly an important aspect of PONV prevention, and increasingly so for patients who present with multiple risk factors. When our anesthesia team set out to improve our PONV prevention protocols, we first attempted to find out how frequently PONV occurred at the hospital where we provide anesthesia services, with an eye on tracking the trend over time. We were surprised to find that the data we were seeking didn't exist. In fact, there hadn't even been a method established for collecting and measuring it.

So we asked how often any type of antiemetic medication was administered in PACU. While we're aware that some providers go the antiemetic route before they deliver post-op pain meds, we wanted an estimate of PONV prevalence for baseline purposes. Our query of 1,010 adult PACU admissions revealed 542 antiemetic administrations for a PONV incidence rate of 53.7%.

The next question: Could we proactively lower the incidence rate with an alternative to routine PACU care? Our search for an evidence-based solution began with an in-depth review of the available medical literature on the complication. We found 2 themes repeating throughout the studies. First, the use of a pre-operative PONV risk screening tool is effective. Second, you should target antiemetic prophylaxis based on risk stratification (see "Who's Most at Risk?").

All angles covered
PONV can lead to post-op complications, including pulmonary aspiration, bleeding, wound dehiscence, dehydration, electrolyte imbalance and esophageal rupture, just to name a few. It lengthens patients' stays in recovery and delays discharge. It doesn't do any favors for patient satisfaction, either.

The matching of interventions to patients for effective relief is easier said than done. Some drugs aren't suitable for some patients, certain patients' comorbidities contraindicate the use of specific agents, and sometimes providers' knowledge deficits mean that potentially useful doses go untried.

That's the necessity of a multimodal approach, and why the targeted prophylaxis specifies minimum numbers of interventions for low-, medium- and high-risk patients. The higher the risk, the more opportunity you have to potentially forestall it.

Your providers must ensure, however, that when multiple interventions are administered, each is selected from different classes of antiemetics. You don't want to give a patient several doses from the same class of drugs; but instead aim to work on different receptors for the best chance at PONV prevention. They must also monitor the incidence of PONV among their patients in PACU in order to determine whether and which of their interventions worked.

PONV POLICY
Who's Most at Risk?

DATA CRUNCHERS Cristina Brooks, BSN, RN, CPAN (left), Andrea Moppin, RN, CCRN (seated) and Chris Smith, CRNA, DNP, review patients' pre-op assessments.

Out in the forefront of PONV prevention literature is the Society for Ambulatory Anesthesia's "Consensus Guidelines for the Management of Postoperative Nausea and Vomiting," published in the January 2014 issue of the journal Anesthesia & Analgesia (osmag.net/pDa6AG). These guidelines, an updated version of SAMBA's 2003 and 2007 recommendations, advise providers to adopt the Apfel simplified risk scoring system to judge adult patients' likelihood of suffering PONV. That means you should score patients during a pre-op assessment using the following PONV risk factors:

• female patients, 1 point;
• non-smokers, 1 point;
• patients who will receive post-op opioids, 1 point; and
• patients with a history of PONV or motion sickness, 1 point;

Totaling the factors gives you a PONV risk score of zero to 4 points. These risk scores are then stratified as follows:

• 0 or 1 point: low risk.
• 2 points: moderate risk.
• 3 or 4 points: high risk.

There is no shortage of options in your antiemetic arsenal. Some of the most common prophylactic options include the following:

• total intravenous technique (TIVA)
• scopolamine patch, 1.5 mg
• ondansetron, 4 to 8 mg IV
• dexamethasone, 4 mg IV
• diphenhydramine, 25 to 50 mg IV or IM
• a peripheral nerve block
• metoclopramide 10 mg IV
• haloperidol, 1 mg IM or IV
• ephedrine 0.5 mg/kg IM
• hydration, 25 ml/kg IV

At our center, patients classified as low risk are administered at least 1 antiemetic intervention. Moderate-risk patients receive at least 2 interventions, and high-risk patients get at least 3. Our approach differed slightly from that described in SAMBA's updated guidelines, in that we chose to treat low-risk patients as well as the moderate- and high-risk ones. Our efforts to improve our preventative protocols focused only on adult patients, but SAMBA's revised guidelines offer additional insights into PONV screening and prophylaxis for pediatric patients, for whom the length of surgery is a significant risk factor and the formulary of antiemetic drugs differs from the adult options.

— Christopher A. Smith, CRNA, DNP

Patient satisfier
Perhaps your pre-op screenings gloss over PONV with a single question: "Have you experienced problems with anesthesia in the past?" What's more, PONV incidence rates often go unrecorded and unreported, even though the use of evidence-based tools can help you identify at-risk patients and take preventive steps against PONV.

Including an evidence-based pre-op screening tool to determine a patient's risk of PONV in the electronic medical records system can help to streamline awareness, assessment and prophylaxis into the process. It will prompt providers to ask the questions that can result in antiemetic interventions, not to mention the tracking of effectiveness. Health care is moving steadily toward performance-based and quality-based efforts. By taking steps to reduce the incidence of PONV, anesthesia providers — who have a big stake in patient satisfaction — will be there.