As laparoscopic techniques have been applied to various diseases and more superior perioperative outcomes than with OS have been found, many studies have reported safety and efficacy findings of LS for the treatment of PPU [9, 15, 16]. Concerns about LS such as a longer operation time, insufficient lavage, and possible repair site leakage seem to be on the decline as LS experience and data have accumulated. A meta-analysis found that LS for PPU has similar short-term outcomes, but less early postoperative pain and wound infection [3, 12]. We also found no difference in postoperative complication rates, the primary endpoint of this case-matched study, between the LS and OS groups. Consistent with previous studies, we also found that LS for PPU yielded better functional recovery than OS, including more rapid diet resumption and a shorter postoperative LOS [10, 16].
The preoperative condition of a patient can affect the decision about the type of surgery used. Traditionally, a patient with poor condition and severe disease would undergo OS rather than LS. Patients with severe peritonitis with a large amount of purulent fluid or with fecal material in the intraperitoneal cavity usually require rapid and massive irrigation rather than use of laparoscopic irrigation, which involves a small-diameter opening and is a slow process. Carbon dioxide retention can occur via intraperitoneal CO2 insufflation during LS, which might affect an unstable patient’s outcome [22]. Therefore, during previous decades OS has been performed in patients with worse factors, including old age, higher ASA score, alcohol consumption, longer symptom duration, a higher Boey score, and poor laboratory results (e.g., for CRP and albumin). We also found significant differences in these variables before propensity score matching. Even though the surgeons in this study had experience using LS for abdominal disorders, patients with more severe conditions tended to undergo OS instead of LS for PPU before matching, especially during the early part of the study period. Therefore, all variables were balanced via matching to reduce the possibility of allocation bias.
Similar to previous meta-analyses that found similar or marginally shorter operation times for LS than OS, operation time was not different in this study (78.17 min LS vs. 82.84 min OS, P = 0.217) [3, 12]. The small difference (about 5 min) might be related to the combination of longer abdominal wall open and closure times, but a shorter primary repair time, of the perforated site in OS compared with LS. Omentopexy rates were same in both groups, but more fibrin sealant application was performed in the OS group than in the LS group. These variables can be affected by (1) the surgeon’s preference and (2) changes related to improvements in laparoscopic instruments and skills. Some investigators reported results using a fibrin glue application for the PPU site in the early 1990 s, but few reports have recently been published [8, 23]. Most fibrin sealant-applied cases were performed during the early period of this study.
Time to diet resumption was shorter in the LS group than the OS group; the subsequent LOS was also shorter. Earlier functional recovery from LS compared with OS has been found in previous studies [5, 7]. Patients who undergo LS for colorectal, gastric, and hepatobiliary disease experience less pain, faster resumption of normal bowel movements, and a shorter LOS than those who undergo OS. Previous studies have also reported similar results for PPU. Lau et al. found that the amount of analgesia required after LS is less than for OS, although the operation time is longer [13]. A randomized controlled trial performed by Bertleff and colleagues found that LS results in low pain scores and shorter hospital stays [16].
There were no between-group differences in specific Clavien-Dindo classification-based postoperative complication rates or in overall rates. The OS group tended to have more complications (24.6% LS vs. 31.7% OS, P = 0.131); this difference might be related to wound-associated complications (7 patients LS vs. 15 patients OS). Wound-associated complications occur more frequently after OS than after LS. Cirocchi et al. found that LS has a lower postoperative wound infection rate than OS for PPU [12].
Based on various outcomes that favor LS more than OS, we believe that LS is an alternative option for successful PPU treatment. Some authors think that LS should be performed only for hemodynamically stable patients [9]. However, we compared the patients’ Boey score data and found no differences associated with preoperative shock. Because of improvements in surgical skills and instruments for LS, better perioperative outcomes can be obtained by LS-experienced surgeons, even in patients who are hemodynamically unstable.
To our knowledge, this study is the largest to date to compare LS and OS for PPU. However, some limitations should be noted. First, the retrospective nature of the study might have affected the results. The nature of the disease, including patient instability, perforation size, and unclear origin of the perforation could have affected the results. Second, propensity score matching was performed to reduce allocation bias, but selection bias was still possible. Third, the analysis was not stratified by participating surgeon or institution; the operation method used could vary by the surgeon’s preference, technique, experience, and the institution’s policies and medical procedures offered. Moreover, most medical records did not reveal the reason LS or OS was chosen. Fourth, the participating surgeons were highly experienced laparoscopic surgeons who had each performed > 200 laparoscopic surgeries. Therefore, these results might be not reproducible in real medical practice where emergent surgery is required. Fifth, postoperative pain is one important variable used to examine efficacy of LS compared with OS. However, postoperative pain was not analyzed because medical records did not include the required data. Sixth, no long-term outcomes such as incisional hernia or recurrence of PPU were recorded because most patients visited the outpatient clinic only once or twice after surgery. Last, we believe the advantages of LS can benefit high-risk patients. However, because propensity matching excluded these patients, we could not examine this hypothesis about LS efficacy using this study design. In addition, patients with an ASA score = 4 were excluded from the analysis because postoperative outcomes of these patients could be predicted by the severity of underlying disease, rather than the surgical method used (OS vs. LS). This question should be examined using well-designed randomized controlled trials.