Is general anesthesia safe for children?
© 2015 Roy Benaroch, MD
Meghan wrote in:
My 10 month old son (a twin) has a mild hypospadias and chordee. The recommendation from our pediatric urologist was surgery at 6 months. Another specialist said that we could wait a few months, which may even lead to better outcomes (due to difference in size) but that we would absolutely need to operate before he was walking and reached ‘genital awareness.’
This surgery requires general anesthesia, and there have been a number of studies published recently (i.e. NEJM and Pediatrics) that suggest that this poses serious risks (learning disabilities, etc.) Of course for life threatening conditions, you would need to operate, but for a non-life threatening condition (mild hypospadias) I wonder if the pros outweigh the potential cons?
I would greatly appreciate your thoughts. The specialists whom I have tried to engage (urologists and anesthesiologists) have been unfortunately, very dismissive to entering into discussions around this issue. Even guidance on who to approach for their thoughts would be so appreciated!
First: hypospadias, if mild, probably doesn’t have to be repaired at all. But that chordee—if that’s present, Junior would appreciate it if you’d get that fixed for him before he has painful erections that don’t (for lack of a better term) work.
What Meghan really wanted to know about was the potential risks of anesthesia, especially in light of recent publications that have brought up questions about anesthesia’s long term affect on children’s brains. Some of these studies have been on animals (both rodents and primates), showing “anesthetic neurotoxicity”—the death of brain cells with exposure to anesthetic agents. But rats and monkeys aren’t people, and we know that brain cells (especially cells in brains of children in intellectually stimulating environments) can regrow and regain function. In fact, it may well be that younger children could conceivably recover from this kind of damage better than adults.
Other studies have been observational, retrospective studies—looking at groups of children who did and did not have exposure to anesthesia. One from a few months ago did show that kids who had anesthesia before age four did have slightly lower IQ scores (tho IQ remained in the normal range for both groups, it was 5-6 points higher in the children who had not had anesthesia.) But these kinds of studies aren’t very reliable. It’s difficult to know, for instance, if the difference is from the anesthesia itself, or from the health condition that necessitated the surgery. That is, kids who require surgery and kids who don’t require surgery aren’t equal in many ways. The ones who need surgery are more likely to have health problems, and maybe that’s why their measured IQ at age four could be lower. Besides, does the IQ at four even matter? What if it’s recovered to the same by school age?
Meghan might think that for what’s going on with her son, which is a genital concern, there wouldn’t be any expected difference in brain strength. But statistically, that’s not true. We know babies born prematurely are more likely to have hypospadias; and we know that babies born prematurely are more likely to have intellectual deficits, ADHD, autism, and cerebral palsy. Statistically speaking, having a hypospadias means you’re more likely to have these other things, too. We also know that the most effect on development and IQ is seen in children who’ve had multiple surgeries (who are also the children most likely to have the most complicated medical histories, like heart disease or brain malformations.) So was is it the anesthesia that’s the risk?
Chicken, meet egg.
The best studies to tease this out haven’t been completed yet, but they’re underway. Children with the same health conditions (for example, a group of boys with hypospadias) need to be randomized so some have surgery now, and some wait a few years. Then they can be followed with periodic neuropsychiatric testing to see how they do. This kind of randomized, prospective study is the best way to isolate a variable (in this case, anesthesia) and establish whether that’s really a risk.
Since those studies haven’t been done yet, for now I’d say: if general anesthesia isn’t required – if the procedure is entirely cosmetic, or can safely be put off until a child is older – it makes sense to wait. But in some cases, there’s a medical benefit to doing surgery earlier. Cleft lip repair early allows for better language development and feeding; a shunt to treat hydrocephalus prevents brain damage when done young; eye muscle surgery allows the development of sharp vision. The potential risk of general anesthesia has to be balanced against the risk of waiting, and there’s no “general rule” that you can apply that could account for all circumstances.
The most troubling part of Meghan’s question was her last comment—that the surgeons and anesthesiologists were dismissive of her concerns. Those are the people she ought to be able to depend on to follow the literature closely and be able to discuss this. If they’re unwilling to take these questions seriously, it’s probably best to Meghan to find some new doctors.