Is there a link between longer operating times and increased risk?

Hardy et al 1 report an independent association between the length of surgery and complication rate. Should the prudent plastic surgeon limit surgery times to about 3 hours and consider staging operations that increase operating time beyond this threshold? As the authors acknowledge, 1 there are some limitations of a retrospective study based on Current Procedural Terminology codes. For example, the largest patient subgroup is labeled " lipectomies. " Presumably, this group includes liposuction cases and abdominoplasties. Liposuction cases are well known to have low complication rates and are typically performed in less than 3 hours. 2 A simultaneous abdominoplasty often increases the operating time to more than 3 hours and introduces additional complications, such as infections, sero-mas, and delayed wound healing. 2 Similarly, breast augmentations , done in about an hour, have a low complication rate. 3 Low-risk breast augmentations and liposuctions favorably affect complication rates for operations lasting less than 3 hours. The difference in procedural representation at different operating times creates the appearance of a link between the complication rate and operating time. To examine the effect of operating time alone, the researcher would need to eliminate confounding variables. The authors recognize the difficulty in separating procedure complexity from surgery time in patients undergoing combined operations. 1 This cannot be done using statistics alone for patients who undergo, on average, 4.9 procedures in 1 operation. The closest one can approach this research ideal would be to study patients undergoing just 1 type of surgery. This study does include 2 groups of such patients: facelift patients and free flap patients. These subgroups showed no significant effect of operating time on the complication rate. 1 A recent study also detected no significant association between the length of surgery and the complication rate after facelifts. 4 These findings indicate that the controlling variable is the type of surgery; the surgery time is only indirectly related to the complication rate. When evaluating other parameters that might be related to an increased complication rate, it is important to consider the patient characteristics of the different procedural groups. For example, low-risk breast augmentations are represented almost entirely by women, who are also likely to be younger than the overall average and thinner. 3 Similarly, low-risk liposuction-only patients are likely to be disproportionately female and younger than the average study patient. 2 An analysis that does not control for these differences is likely to …