In a study that has relevance for the ongoing debate about anesthetic neurotoxicity in children, researchers have identified predictors of increased anesthetic duration for some of the most common pediatric general surgeries.
Given the possible association between duration of anesthetic exposure and long-term cognitive deficits, understanding predictors of variability may be useful in identifying patients at risk for anesthetic neurotoxicity.
Factors that were found to be predictive of significantly longer anesthetic duration for a particular procedure type included:
- ASA physical status III and IV;
- patients less than 1 year of age and between 1 and 3 years; and
- procedures at university hospitals.
Although anesthetic duration was shown to vary widely among the procedures, “this study is the first to describe variability in surgery and anesthesia time for pediatric procedures using a large, multicentered database, and there are potential implications for booking times and operating room efficiency,” said Anna J. Klausner, MD, NewYork-Presbyterian/Columbia University Medical Center, in New York City. “Perhaps the hour that the surgeon books for the appendectomy is not necessarily correct.
“In the current day of neurotoxicity research, we can also use these data to look at children that might be at increased risk for having longer durations of procedures,” added Caleb Ing, MD, who co-authored the study with Dr. Klausner.
According to Dr. Ing, although predictors of anesthetic duration have been explored in adults—a multicenter study found increased anesthesia time was associated with race, coagulation disorders and paraplegia—only one such study exists in the pediatric literature.
Parsing the Data
For this study, Drs. Klausner and Ing queried the National Anesthesia Clinical Outcomes Registry database for records of children (<18 years of age) who had received anesthesia for one of the 10 most common inpatient general surgical procedures performed in the United States, according to the 2009 Kids’ Inpatient Database. These procedures included:
- central venous access
- burn debridement/graft
- patent ductus arteriosus ligation
- bladder/ureter reconstruction
- antireflux surgery
- inguinal hernia repair
- gastrostomy tube placement
In order to remove outlier records, patients in the 0.5 percentile of the shortest and longest durations for each procedure were excluded, leaving 99% of the records for each procedure available for analysis.
As Dr. Klausner reported at the International Anesthesia Research Society 2017 annual meeting (abstract 1636), a total of 139,879 records were identified. Although the median duration of most pediatric procedures ranged from 71 to 93 minutes, longer median durations were found with antireflux procedures and bladder ureter reconstruction, whereas shorter median durations were observed for gastrostomy tube placement. According to the researchers, the durations of anesthetic care within procedures also varied significantly, with the highest duration decile ranging from 2.0 to 4.7 times longer than the lowest decile.
“Even procedures like an appendectomy or gastrostomy tube placement had significant variability,” Dr. Klausner said. “We assume these surgeries are really quick and are not exposing children to that much anesthesia, but that is not always the case.”
Using Poisson regression, the researchers then evaluated the association between the duration of anesthesia and patient- and hospital-level covariates. Children with ASA physical status III and IV had significantly longer procedures compared with ASA I patients, with increases of 12.5 and 32.4 minutes, respectively. Children less than 1 year of age and between 1 and 3 years also had significantly longer procedures compared with children over the age of 10, with increases of 19.3 and 11.5 minutes, respectively. Finally, procedures at university hospitals also required more time compared with surgery centers (20.7 minutes longer) and small community hospitals (18.5 minutes longer).
Just Getting Started
According to the investigators, however, their work has just begun. As Dr. Klausner reported, Pediatric Anesthesia & Neurodevelopment Assessment (PANDA) recently published its first benchmark paper exploring single exposures for children under 3 years of age. The PANDA paper showed that in healthy children with a single exposure of less than three hours, there is no increase in incidence of postoperative or long-term cognitive deficit.
“Maybe the population in our study is getting exposed longer than we initially thought,” Dr. Klausner said. “Perhaps that’s something we ought to examine in the future.”
“What’s the next step for your institution?” asked Ahmed Attaallah, MD, PhD, of West Virginia University, in Morgantown. “Are there things you can improve at your respective hospitals to reduce [anesthetic] exposure?”
“It will be challenging from a scheduling standpoint to apply these results to our respective institutions,” Dr. Ing acknowledged. “But from a neurotoxicity standpoint, estimating the duration of procedures can inform us that appendectomies or gastrostomy placements are not necessarily uniformly short procedures. There could also be some surgeons at centers who take significantly longer than others. In other words, based on these data, we can no longer maintain that certain procedures are free from neurotoxicity risk if duration is proven to be a factor.”
“With the change in outcome monitoring, this is the kind of work that anesthesiologists need to be doing,” Dr. Attaallah said. “I’d like to see more of us involved in the perioperative surgical home, improving patient care.”