Intra-Op Opioids Heighten Risk for PDNV in Children

The administration of intraoperative opioids was significantly associated with post-discharge nausea and vomiting (PDNV) in children, and long-acting opioids had far worse effects than their short-acting counterparts.

“This study started out along the lines of a quality-assurance project into unexplored territory in children,” said Proshad Efune, MD, currently a fellow in the Pediatric Critical Clinical Care Department at Children’s Medical Center, in Dallas. “We wanted to get an idea of how we were doing in terms of PDNV in our children, and it evolved into this study.” Previous research has estimated the rate of PDNV to be 3% to 17%, depending on the type of surgery (Anaesthesist 2013;62:707-719).

To help determine the risk factors for PDNV in children following outpatient surgery, Dr. Efune and her colleagues at the University of Texas Southwestern Medical Center/Children’s Medical Center, in Dallas, queried patients’ parents by phone on the day after the procedure. The survey examined the presence and frequency of nausea and vomiting, its relationship to eating/drinking or riding in a car, and its relationship to intraoperative and postoperative opioid use. Other recorded variables included type of surgery and anesthetic, and whether opioids or antiemetics were administered intraoperatively.

As reported at the 2015 annual meeting of the American Society of Anesthesiologists (abstract A4074), data were available from 1,021 children, 142 of whom experienced PDNV (13.9%). “Certain risk factors that we thought were going to be important turned out not to be, and vice versa,” Dr. Efune said, “and I think we ended up with some really interesting results.”

And Long-Acting More So…

Most notably, the researchers found a significant difference in PDNV rate between patients who did not receive any intraoperative opioids (8.3%), those who received short-acting opioids only (14.4%) and those who received long-acting opioids (25.3%). There was also a significant difference between patients who received opioids at home after discharge and those who did not, with 29.5% and 12.6%, respectively, experiencing PDNV.

No associations were found between PDNV and patient age, sex, intraoperative antiemetic administration, time from PACU discharge to first oral intake, or length of ride home from the hospital.

“Being a pediatric tertiary care center, we get a lot of referrals from all over Texas,” Dr. Efune said in an interview with Anesthesiology News. “And sometimes our kids will drive three or four hours home after a procedure, so we thought they would be at higher risk of PDNV. But as it turns out, there was no difference. It didn’t matter if the car ride home was 10 minutes or four hours.” Although no association was found between the time to first oral intake or length of ride home and PDNV, parents reported that oral intake preceded PDNV in 57% of patients and riding in a car preceded PDNV in 47.9%.

Incidence of PDNV differed significantly by type of procedure, with tonsillectomy and/or adenoidectomy resulting in the highest incidence (26.6%). Of the 142 patients who experienced PDNV, 14.8% (2% of the total sample size) continued to vomit the day after discharge; 4.8% (0.67% of the total sample size) continued to vomit two days following discharge.

Role of Antiemetics

Some of these findings proved intuitive, Dr. Efune said, whereas others were more surprising. “We know that opioids increase nausea and vomiting, so that part made sense. On the other hand, we always thought that intraoperative antiemetics would make a difference in terms of PDNV, but it seems the effect of the opioids outlasts the effect of the antiemetics, particularly in the case of intraoperative administration of long-acting opioids.”

She cautioned her colleagues to be aware of the high risk for PDNV associated with the intraoperative administration of long-acting opioids. “And if the surgeon is planning on discharging the patient home with opioids, think about avoiding long-acting opioids in the [operating room], because it only compounds the risk. Another consideration is sending children home with Zofran [GlaxoSmithKline; ondansetron] because of the risk of PDNV.”

In most cases, short-acting opioids can be easily substituted for long-acting ones, she added. “You have to be aware that you may have to redose sometime during the case,” Dr. Efune said. “So it’s really just a question of style and knowing the pharmacokinetics of the drugs you’re working with.”

Rosalie Tassone, MD, told Anesthesiology News that the trial opens the door for clinicians to preemptively address a troubling side effect. “This study reinforces what we have often suspected with respect to opioids and post-discharge nausea and vomiting,” said Dr. Tassone, vice chair of anesthesiology and chief of the Division of Pediatric Anesthesiology at Sidra Medical and Research Center, in Doha, Qatar. “Based on this work, I am curious if we should consider looking at prescribing antiemetics to patients who receive narcotics postoperatively and are going home. I look forward to further work in this area.”