Preventing PONV in Pediatric Patients

Effective strategies require a proactive approach to identifying risk factors and the targeted administration of prophylactic agents.

No provider wants their patients to feel nauseous in recovery, but the importance of preventing one of surgery’s most dreaded complications seems a bit higher when children are involved — especially because kids are twice as likely as adults to experience PONV. “The etiology of pediatric PONV is complex,” says Robert W. Simon, DNP, MS, CRNA, CHSE, CNE, chief CRNA at Huntington Valley (Pa.) Anesthesia Associates. “Some studies point to the age of the patient and immature receptor development as a potential cause, where other reports suggest the type of surgery and anesthesia play the biggest role.” The rate of PONV in children ranges from 42% in low-risk patients to as high as 80% in high-risk patients, and PONV is the fourth most common cause of unexpected hospital admissions in pediatric surgical patients, notes a paper Dr. Simon authored in AANA Journal.

Although there is no consensus as to why pediatric patients are at increased risk of PONV, there are several factors that could play a role, according to Sarah Kukura, CRNA, a nurse anesthetist at Nationwide Children’s Hospital in Columbus, Ohio. She says the lack of a consistent screening method for PONV in children continues to be an issue. Additionally, children may not be able to communicate certain factors that put them at risk.

“For example, a young child might experience motion sickness but not be aware of what they’re experiencing or be able to share that information with providers,” says Ms. Kukura. “As a result, providers could miss risk factors that likely wouldn’t be missed in adults. Children who are inadequately screened for PONV may end up 
getting inadequate prophylaxis intraoperatively and therefore have an increased likelihood of suffering the complication.”

Efforts to prevent PONV in children extend beyond the recovery room, according to Ms. Kukura. “In addition to the emotional impact, PONV can result in prolonged postoperative stays and unplanned hospital admissions,” she says. “PONV that occurs after major surgery — craniotomy and spinal fusion, for example — has physiologic effects that can be very detrimental, such as increased intracranial pressure and wound dehiscence. Aside from these being very unfortunate outcomes for pediatric patients, PONV events can also have very real effects on parents, who could incur higher medical bills and may end up needing to take time off from work to care for their children.”

There’s no arguing the importance of lowering the risk of PONV in pediatric patients, but prevention is easier said than done.

Identifying the issue

Dr. Simon says the identification of PONV risk in pediatric patients is largely disorganized and inconsistent due to a lack of knowledge among healthcare providers regarding screening tools and their failure to use an evidence-based risk scoring system despite documented benefits of doing so. He says the first step of prevention is establishing a standardized protocol for screening patients for risk factors, which include surgical time greater than 30 minutes, a history of motion sickness or PONV, age greater than three years, use of inhalational anesthetics and opioid administration. “Instituting and utilizing a pediatric PONV screening tool to help identify high-risk patients is essential,” says Dr. Simon.

Society of Ambulatory Anesthesia guidelines suggest using a simplified screening tool to evaluate baseline risk factors and classify patients as low, medium or high risk. Multiple preoperative screening tools are available, but the Eberhart’s postoperative vomiting in children (POVOC) score was created specifically for pediatric patients. It identifies history of PONV, history of motion sickness, duration of surgery longer than 30 minutes, age older than three years, strabismus surgery and family history of PONV or motion sickness as risk factors.

According to the POVOC scoring system, patients who present for surgery with none or one risk factor should receive no prophylactic antiemetics and be treated for PONV as it occurs; children with two or more risk factors should receive two prophylactic antiemetics (ondansetron, dexamethasone or droperidol); and patients with three or more risk factors require prophylactic antiemetics and modification of their anesthesia management, which can include adequate hydration and the avoidance of potential triggers such as inhalational anesthetics and nitrous oxide. Although it’s common for adults with a history of PONV to receive a total intravenous anesthetic (TIVA), that’s not a common practice at Nationwide Children’s, where pediatric patients receive volatile anesthetics, which increases the likelihood that they experience PONV — and raises the importance of implementing preventative measures.

Multimodal approaches

MEDICATION MANAGEMENT Administering dexamethasone and ondansetron prophylactically during surgery or therapeutically in the PACU is an effective treatment strategy.

Dr. Simon says the appropriate use of dexamethasone and ondansetron in combination has been effective in preventing PONV in children. “The doses of these medications should be based on the individual patient’s weight and should not exceed the recommended max dosing,” he says. “These medications may be contraindicated in pediatric patients with certain medical conditions, allergies or disease processes, so care and consideration must be used prior to use.”

Prolonged NPO times could cause patients to become dehydrated and therefore increase their PONV risk, points out Ms. Kukura. Providers at Nationwide Children’s attempt to address this issue by encouraging patients to continue drinking clear liquids up until two hours before their procedures instead of fasting for eight hours beforehand.

NPO guidelines in children are age-specific and difficult to generalize, according to Dr. Simon, who says prevention strategies should therefore be based on individual patients and specific cases. In general, says Dr. Simon, adequate IV hydration is helpful in preventing the complication. “Many factors contribute to the development of PONV,” he says. “This means there isn’t a one-size-fits-all approach to managing it.” Some patients, he points out, can benefit from aromatherapy and acupressure.

“Although I don’t have specific data about their effectiveness, I do believe that alternative methods have a place in PONV prevention and treatment,” says Ms. Kukura. “We offer alternative therapies such as aromatherapy and music therapy at our facility.”

The novel antiemetic agent aprepitant, which prevents vomiting related to the administration of chemotherapy, has also been used with increasing frequency to prevent PONV in the adult and pediatric patient populations. In February 2018, Nationwide Children’s added aprepitant to its EMR and perioperative formulary. The option to administer the drug was added to the anesthesia preoperative order set for use as prophylaxis against or the treatment of PONV. Anesthesia providers were educated on aprepitant’s dosing, administration and indication through emails and presentations at departmental meetings, and the drug was added to automated dispensing cabinets in the pre-op area.

Ms. Kukura says Nationwide Children’s uses aprepitant as part of its multimodal approach to reduce the incidence of PONV in children. Providers use a standardized screening tool to identify patients at increased risk and implement a perioperative prevention regimen based on the procedures they’re scheduled to undergo. For example, spine surgery patients are given aprepitant and have a scopolamine patch applied in pre-op. They’re then administered ondansetron and dexamethasone during surgery or in the PACU to treat PONV. The regimen has cut their hospital stays in half, according to Ms. Kukura. 

During a recent study Ms. Kukura co-authored in Journal of Current Surgery, aprepitant was used at Nationwide Children’s to treat high-risk patients and during procedures associated with an increased risk of PONV. The study included 144 patients between the ages of seven and 17 years who underwent gastrointestinal, orthopedic and otolaryngologic procedures. All but two of the patients received one antiemetic in addition to aprepitant, and 83% of the patients received at least two additional antiemetics.

PONV occurred in fewer than 11.8% of these high-risk patients and was not listed as the primary reason for unplanned hospital admissions, a rate at the low end of the reported post-op range for children and similar to results in adult patients. Aprepitant’s overall tolerability was good, and no serious adverse events occurred in any of the patients.

Whether it’s new medications, alternative approaches or proven antiemetics, providers need to take the necessary steps to prevent PONV. Children, perhaps more than any other patients, shouldn’t suffer while they’re recovering from surgery. OSM