Abstract
Background
Children with congenital heart disease (CHD) often require non-cardiac surgery. We compared outcomes following open and laparoscopic intra-abdominal surgery among children with and without CHD.
Methods
We performed a retrospective cohort study using the 2013–2015 National Surgical Quality Improvement Project-Pediatrics. We matched 45,012 children <18 years old who underwent laparoscopic surgery to 45,012 children who underwent open surgery. We determined the associations between laparoscopic (versus open) surgery and 30-day mortality, in-hospital mortality, 30-day morbidity, and postoperative length-of-stay.
Results
Among children with minor CHD, laparoscopic surgery was associated with lower 30-day mortality (Odds Ratio [OR] 0.34 [95% Confidence Interval 0.15–0.79]), inhospital mortality (OR 0.42 [0.22–0.81]) and 30-day morbidity (OR 0.61 [0.50–0.73]). As CHD severity increased, this benefit of laparoscopic surgery decreased for 30-day morbidity (ptrend=0.01) and in-hospital mortality (ptrend=0.05), but not for 30-day mortality (ptrend=0.27). Length-of-stay was shorter for laparoscopic approaches for children at cost of higher readmissions. On subgroup analysis, laparoscopy was associated with lower odds of postoperative blood transfusion in all children.
Conclusions
Intra-abdominal laparoscopic surgery compared to open surgery is associated with decreased morbidity in patients with no CHD and lower morbidity and mortality in patients with minor CHD, but not in those with more severe CHD.
Keywords: NSQIP, pediatric surgery, mortality, morbidity, laparoscopic surgery, congenital heart disease
1. Introduction
Congenital heart disease (CHD) affects approximately 10 per 1,000 live births in the United States [1]. As these children survive longer due to improvements in diagnosis and treatment, nearly half are expected to need additional non-cardiac surgeries by age 5 years [2, 3]. CHD is associated with an increased risk of mortality and morbidity following non-cardiac surgery [4–6]. However, less is known about the impact of laparoscopic or open approaches on postoperative outcomes in this particularly vulnerable and increasingly more prevalent patient population.
Numerous intra-abdominal operations in children can be performed either open or laparoscopically [7]. Meta-analyses for specific procedures such as laparasocopic appendectomy among healthy children results in less postoperative pain and shorter hospitalization compared to open [8, 9]. However, these studies have typically excluded children with CHD, who may be more vulnerable to the deleterious effects of pneumoperitoneum on cardiopulmonary physiology [10–13]. Recent studies that reported laparoscopic surgery is safe in children with CHD have been limited to either highly select patient populations, such as infants or single procedures, or single-institution non-comparative series [14–18]. Therefore, a more generalizable comparison of outcomes of laparoscopic versus open surgery for children with CHD is lacking.
In this cohort study, we compared outcomes of open and laparoscopic intra-abdominal surgery among children of all ages with different severities of CHD using data collected in the American College of Surgeons National Surgical Quality Improvement Program-Pediatrics (NSQIP-P). We hypothesized that any mortality and morbidity advantage of laparoscopic over open surgery is attenuated by greater severity of CHD.
2. Methods
2.1. Design and Data Source
This is a retrospective cohort study using data collected in NSQIP-P from 2013 to 2015. Because the dataset is completely de-identified, this study was determined to be non-human subjects research and deemed exempt from review by our institutional review board.
The NSQIP-P dataset contains information on children <18 years of age undergoing non-cardiac surgery at participating hospitals throughout the United States. The number of participating hospitals increased from 56 in 2013, to 64 in 2014, to 80 in 2015, and include freestanding general acute care children’s hospitals, children’s hospitals within a larger hospital, specialty children’s hospitals, and general acute care hospitals with a pediatric wing. NSQIP-P contains detailed information on demographic characteristics such as age, sex, and race, perioperative characteristics such as case urgency and procedure code, and postoperative complications such as unplanned readmissions, reintubation, and mortality. Data were collected up to 30-days after surgery, although discharge and death data were available if patients were still hospitalized past the 30-day window. Each participating hospital has a full-time, trained and certified surgical clinical reviewer who conducts data entry and routine audits to ensure accuracy, completeness, and precision. NSQIP-P has an overall inter-rater reliability of 98% [19]. A systematic sampling strategy is employed by each surgical clinical reviewer to reduce selection bias within and between hospitals. Hospitals which had an inter-rater reliability disagreement rate >5% and/or 30-day follow-up rate <80% were excluded per NSQIP-P criteria [19].
2.2. Participants
Children ages 0 to 17 years old who underwent any intra-abdominal operation in 2013, 2014, and 2015 were included. Those who were missing an indicator variable indicating laparoscopic or open surgery were excluded.
2.3. Exposures
The primary exposure was laparoscopic surgery, which was ascertained using an indicator variable defined by NSQIP-P beginning in 2013. This indicator variable stratified cases into laparoscopic only, combination open/laparoscopic, and open only surgeries. For our primary analysis, laparoscopic and combination open/laparoscopic cases were combined into “laparoscopic surgery”. Procedures were identified using Common Procedural Terminology (CPT) codes. Regardless of whether procedures had separate laparoscopic CPT codes or none, the indicator variable was used to stratify laparoscopic from open surgery. To control for potential effects of pneumoperitoneum on outcomes, our analysis was restricted to intra-abdominal procedures, leaving 46 total surgical procedures (Appendix Table A.1.).
2.4. Outcomes
The primary outcome was 30-day mortality. This was chosen for two reasons: first, mortality is a highly pertinent outcome after surgery in high-risk patients; and second, 30-day mortality may more accurately reflect episodes of care and depends less on inter-hospital differences than in-hospital mortality [20]. Secondary outcomes included inhospital postoperative mortality, defined as any in-hospital death occurring during the same hospitalization after surgery regardless of whether it occurred within the 30-day postoperative window; 30-day postoperative morbidity; and postoperative length of stay (LOS).
30-day morbidity was a composite outcome comprising any 30-day postoperative complication, excluding mortality. These included: surgical site infection (SSI), pneumonia, urinary tract infection, central line-associated blood stream infection, unplanned reintubation, renal insufficiency, venous thrombotic events, neurologic sequelae (coma, seizure, stroke, nerve injuries), myocardial infarction (MI), sepsis, transfusion (defined as packed or whole red blood cell transfusions from start of surgery to 72 hours post-operatively), unplanned readmission, or unplanned reoperation. This composite measure of morbidity, as defined in previous NSQIP-P studies, was chosen because of the expected overall low incidence of individual adverse events [6, 21]. Morbidity outcome events were based on the number of patients experiencing any complication, rather than number of complications per patient. Postoperative LOS was calculated as days of hospitalization from operation until discharge or death.
2.5. Covariates
CHD severity was classified as none (absent), minor, major, and severe (Appendix Table A.2.). These definitions, defined by NSQIP-P, classified CHD severity based on repair status and residual hemodynamic abnormality and have been utilized in other studies of postoperative outcomes in children with CHD [4, 6, 16].
The following pre-specified clinical characteristics were ascertained and included in the multivariate matching to balance cohorts (described below): age at surgery (continuous), sex, race (non-Hispanic white, non-Hispanic black, and other), year of operation, American Society of Anesthesiologists (ASA) physical status class (1, 2, 3, 4, 5), preoperative ventilator-dependence, preoperative inotrope-dependence, case urgency (elective versus non-elective), weight at surgery (continuous), gestational age at birth (>36 weeks, 31–36 weeks, 25–30 weeks, <25 weeks, unknown), history of chronic lung disease or bronchopulmonary dysplasia, and number of concurrent procedures (1, 2, >2).
Operative time was not included as a covariate given its role as an intermediate variable on the causal pathway between our exposure of interest and outcomes, which may induce bias.[22] As part of the hospital agreements with NSQIP-P, no data that could potentially identify individual hospital were included in the released databases; therefore, no hospital-level information was available for analysis.
2.6. Statistical Analysis
2.6.1. Matching Algorithm
Within each stratum of CHD severity, a patient who underwent laparoscopic surgery was matched 1:1 with a patient who underwent the same operation but via open approach. Each pair was exactly matched on the type of operation and also matched on the pre-specified covariates, which was done by minimizing the Mahalonobis distance between laparoscopic and open patients using a caliper of 0.1 standard deviations [23]. Matching was done with replacement of patients who underwent open surgery to ensure best matches and maximize analysis of laparoscopic cases [24]. All matches were performed before viewing outcomes [25]. The five most frequently matched operations within each stratum of CHD are shown in Appendix Table A.3.
Chi-square and Wilcoxon rank-sum tests compared categorical and continuous variables, respectively. Differences in clinical characteristics between patients who had laparoscopic and open surgery before and after matching were assessed using standardized mean differences (SMD), with values <0.2 deemed acceptable [26, 27].
2.6.2. Outcome Comparison
The associations between laparoscopic surgery and dichotomous outcomes were estimated using three separate conditional logistic regression models for each stratum of CHD severity. Due to the limited number of outcome events and because cohorts were balanced across covariates after matching, surgical approach was the only independent variable in the models. Tests for trend across strata of CHD severity were performed using likelihood ratio tests of interaction terms for CHD severity and surgical approach.
For postoperative LOS, which is a nonparametric continuous variable, we used generalized estimating equations with clustering on each matched pair and the sandwich robust covariance estimator [28]. Because of missing and negative LOS values, postoperative LOS analyses were performed using complete case analysis in those patients with a postoperative LOS greater than or equal to 0 (signifying outpatient procedure). This smaller cohort constituted 98% of the original matched cohort.
In exploratory analyses, we examined subgroups of postoperative morbidity hypothesized a priori to differ between laparoscopic and open procedures: unplanned readmissions, transfusions, reintubations, MI, and SSI. We also restricted our mortality and morbidity analyses to infants ≤1-year-old, as this group may be the most vulnerable to adverse outcomes [14, 16], and to the most common procedure, initial gastrostomy. As a sensitivity analysis, we restricted analysis to patients undergoing only a single procedure without concurrent procedures, in case of residual confounding or selection bias from the additional procedures. Second, we recoded combination open/laparoscopic cases (which includes laparoscopic surgeries that were converted to open) as open surgeries, which constituted 2–6% of cases within CHD groups, as this may indicate a sudden adverse intraoperative episode such as acute bleeding and lead to worse postoperative outcomes.
All analyses were performed in Stata (v.14, StataCorp LP, College Station, TX) with a two-tailed alpha of 0.05.
3. Results
Within the 2013–2015 NSQIP-P datasets, 70,133 children met eligibility criteria and were included in the analyses. Of these, 25,045 (35.7%) and 45,088 (64.3%) children underwent open and laparoscopic intra-abdominal surgery, respectively (Table 1). By CHD severity, 704 (1.0%), 3,697 (5.3%), 4,102 (5.8%), and 61630 (87.9%) children had severe, major, minor, and no CHD, respectively. Before matching, significant differences in covariates including age, weight at surgery, ASA class, and baseline ventilator-dependence were noted between open and laparoscopic operations, with laparoscopic surgery performed more often in older, heavier, and healthier children without ventilator-dependence.
Table 1.
Baseline cohort characteristics (unmatched).
| Variable | Laparoscopic | Open | p | SMD |
|---|---|---|---|---|
| Overall, No. (%) | 45088 (64.3) | 25045 (35.7) | ||
| Severe CHD, No. (%) | 368 (52.3) | 336 (47.7) | ||
| Age, median (IQR), yr | 0.4 (0.1–1.5) | 0.3 (0.1–0.7) | <0.001 | 0.26 |
| Male | 209 (56.8) | 194 (57.7) | 0.80 | 0.02 |
| Race | 0.10 | 0.002 | ||
| NHW | 204 (55.4) | 195 (58.0) | ||
| NHB | 57 (15.5) | 34 (10.1) | ||
| Other | 107 (29.1) | 107 (31.9) | ||
| Year of surgery | 0.76 | 0.05 | ||
| 2013 | 109 (29.6) | 103 (30.7) | ||
| 2014 | 110 (29.9) | 106 (31.6) | ||
| 2015 | 149 (40.5) | 127 (37.8) | ||
| ASA | <0.001 | 0.18 | ||
| 1 | 0 (0.0) | 4 (1.2) | ||
| 2 | 22 (6.0) | 19 (5.7) | ||
| 3 | 207 (56.3) | 143 (42.6) | ||
| 4 | 138 (37.5) | 167 (49.7) | ||
| 5 | 1 (0.3) | 3 (0.9) | ||
| Elective surgery | 326 (88.6) | 256 (76.2) | <0.001 | 0.33 |
| Weight at surgery, median (IQR), kg | 5.5 (3.7–9.8) | 4.4 (3.4–7.1) | <0.001 | 0.22 |
| Prematurity (<37wks) | 0.01 | 0.13 | ||
| None | 302 (82.1) | 243 (72.3) | ||
| 31–36wks | 47 (12.8) | 70 (20.8) | ||
| 25–30wks | 8 (2.2) | 15 (4.5) | ||
| <25wks | 1 (0.3) | 3 (0.9) | ||
| Unknown | 10 (2.7) | 5 (1.5) | ||
| Inotrope-dependence | 15 (4.1) | 27 (8.0) | 0.03 | 0.17 |
| Chronic lung disease | 42 (11.4) | 44 (13.1) | 0.50 | 0.05 |
| Vent-dependence | 40 (10.9) | 81 (24.1) | <0.001 | 0.35 |
| No. of simult. procs | 0.16 | 0.05 | ||
| 1 | 229 (62.2) | 196 (58.3) | ||
| 2 | 129 (35.1) | 136 (40.5) | ||
| 3+ | 10 (2.7) | 4 (1.2) | ||
| Major CHD, No. (%) | 1614 (43.7) | 2083 (56.3) | ||
| Age, median (IQR), yr | 0.5 (0.2–1.4) | 0.2 (0.03–0.6) | <0.001 | 0.33 |
| Male | 837 (51.9) | 1192 (57.2) | 0.001 | 0.11 |
| Race | 0.002 | 0.12 | ||
| NHW | 871 (54.0) | 1004 (48.2) | ||
| NHB | 278 (17.2) | 385 (18.5) | ||
| Other | 465 (28.8) | 694 (33.3) | ||
| Year of surgery | 0.59 | 0.03 | ||
| 2013 | 395 (24.5) | 522 (25.1) | ||
| 2014 | 479 (29.7) | 641 (30.8) | ||
| 2015 | 740 (45.9) | 920 (44.2) | ||
| ASA | <0.001 | 0.32 | ||
| 1 | 12 (0.7) | 18 (0.9) | ||
| 2 | 200 (12.4) | 196 (9.4) | ||
| 3 | 1052 (65.2) | 1090 (52.3) | ||
| 4 | 348 (21.6) | 722 (34.7) | ||
| 5 | 2 (0.1) | 57 (2.7) | ||
| Elective surgery | 1382 (85.6) | 1412 (67.8) | <0.001 | 0.43 |
| Weight at surgery, median (IQR), kg | 5.4 (3.8–9.7) | 3.6 (2.6–6.5) | <0.001 | 0.35 |
| Prematurity (<37wks) | <0.001 | 0.11 | ||
| None | 966 (59.9) | 1078 (51.8) | ||
| 31–36wks | 304 (18.8) | 409 (19.6) | ||
| 25–30wks | 194 (12.0) | 414 (19.9) | ||
| <25wks | 88 (5.5) | 160 (7.7) | ||
| Unknown | 62 (3.8) | 22 (1.1) | ||
| Inotrope-dependence | 34 (2.1) | 226 (10.9) | <0.001 | 0.36 |
| Chronic lung disease | 407 (25.2) | 533 (25.6) | 0.80 | 0.01 |
| Vent-dependence | 263 (16.3) | 755 (36.3) | <0.001 | 0.47 |
| No. of simult. procs | 0.10 | 0.04 | ||
| 1 | 923 (57.2) | 1216 (58.4) | ||
| 2 | 623 (38.6) | 806 (38.7) | ||
| 3+ | 68 (4.2) | 61 (2.9) | ||
| Minor CHD, No. (%) | 1860 (45.3) | 2242 (54.7) | ||
| Age, median (IQR), yr | 0.6 (0.2–4.5) | 0.4 (0.1–1.4) | <0.001 | 0.34 |
| Male | 1056 (56.8) | 1331 (59.4) | 0.09 | 0.05 |
| Race | 0.45 | 0.04 | ||
| NHW | 1010 (54.3) | 1174 (52.4) | ||
| NHB | 342 (18.4) | 423 (18.9) | ||
| Other | 508 (27.3) | 645 (28.8) | ||
| Year of surgery | 0.001 | 0.12 | ||
| 2013 | 463 (24.9) | 660 (29.4) | ||
| 2014 | 545 (29.3) | 670 (29.9) | ||
| 2015 | 852 (45.8) | 912 (40.7) | ||
| ASA | <0.001 | 0.22 | ||
| 1 | 53 (2.9) | 62 (2.8) | ||
| 2 | 491 (26.4) | 440 (19.6) | ||
| 3 | 1139 (61.2) | 1366 (60.9) | ||
| 4 | 174 (9.4) | 352 (15.7) | ||
| 5 | 3 (0.2) | 22 (1.0) | ||
| Elective surgery | 1499 (80.6) | 1608 (71.7) | <0.001 | 0.21 |
| Weight at surgery, median (IQR), kg | 6.4 (4.0–15.3) | 4.8 (2.9–9.5) | <0.001 | 0.37 |
| Prematurity (<37wks) | <0.001 | 0.18 | ||
| None | 1027 (55.2) | 1009 (45.0) | ||
| 31–36wks | 322 (17.3) | 424 (18.9) | ||
| 25–30wks | 321 (17.3) | 506 (22.6) | ||
| <25wks | 122 (6.6) | 258 (11.5) | ||
| Unknown | 68 (3.7) | 45 (2.0) | ||
| Inotrope-dependence | 12 (0.7) | 90 (4.0) | <0.001 | 0.23 |
| Chronic lung disease | 488 (26.2) | 613 (27.3) | 0.43 | 0.03 |
| Vent-dependence | 179 (9.6) | 399 (17.8) | <0.001 | 0.24 |
| No. of simult. procs | <0.001 | 0.08 | ||
| 1 | 1171 (63.0) | 1294 (57.7) | ||
| 2 | 627 (33.7) | 888 (39.6) | ||
| 3+ | 62 (3.3) | 60 (2.7) | ||
| No CHD, No. (%) | 41246 (66.9) | 20384 (33.1) | ||
| Age, median (IQR), yr | 10.2 (4.8–14.1) | 3.9 (0.4–10.4) | <0.001 | 0.64 |
| Male | 23640 (57.3) | 11586 (56.8) | 0.26 | 0.01 |
| Race | 0.08 | 0.01 | ||
| NHW | 23938 (58.0) | 11686 (57.3) | ||
| NHB | 4580 (11.1) | 2378 (11.7) | ||
| Other | 12728 (30.9) | 6320 (31.0) | ||
| Year of surgery | <0.001 | 0.15 | ||
| 2013 | 11865 (28.8) | 6950 (34.1) | ||
| 2014 | 12494 (30.3) | 6493 (31.9) | ||
| 2015 | 16887 (40.9) | 6941 (34.1) | ||
| ASA | <0.001 | 0.43 | ||
| 1 | 14519 (35.2) | 4353 (21.4) | ||
| 2 | 19846 (48.1) | 9568 (46.9) | ||
| 3 | 6513 (15.8) | 5591 (27.4) | ||
| 4 | 363 (0.9) | 796 (3.9) | ||
| 5 | 5 (0.01) | 76 (0.4) | ||
| Elective surgery | 16791 (40.7) | 11948 (58.6) | <0.001 | 0.36 |
| Weight at surgery, median (IQR), kg | 35.6 (17.7–56.5) | 15.9 (6.7–34.8) | <0.001 | 0.61 |
| Prematurity (<37wks) | <0.001 | 0.21 | ||
| None | 31209 (75.7) | 15827 (77.6) | ||
| 31–36wks | 2075 (5.0) | 1918 (9.4) | ||
| 25–30wks | 590 (1.4) | 905 (4.4) | ||
| <25wks | 113 (0.3) | 220 (1.1) | ||
| Unknown | 7259 (17.6) | 1514 (7.4) | ||
| Inotrope-dependence | 57 (0.1) | 190 (0.9) | <0.001 | 0.11 |
| Chronic lung disease | 584 (1.4) | 647 (3.2) | <0.001 | 0.12 |
| Vent-dependence | 331 (0.8) | 723 (3.6) | <0.001 | 0.19 |
| No. of simult. procs | <0.001 | 0.44 | ||
| 1 | 35945 (87.2) | 14083 (69.1) | ||
| 2 | 5112 (12.4) | 6083 (29.8) | ||
| 3+ | 189 (0.5) | 218 (1.1) |
Values are No. (%) unless otherwise specified.
ASA = American Society of Anesthesiologists physical status; CHD = congenital heart disease; NHW = non-Hispanic whites; NHB = non-Hispanic blacks; SMD = standardized mean difference.
After matching, 45,012 pairs were analyzed, of which 355, 1,579, 1,843, and 41,235 matched pairs were in the severe, major, minor, and no CHD groups, respectively (Table 2). Excellent balance was observed across all strata of CHD severity (Table 2). The frequencies of individual outcomes from the matched cohorts are shown in Appendix Table A.4.
Table 2.
Matched cohort characteristics.
| Variable | Laparoscopic | Open | p | SMD |
|---|---|---|---|---|
| Overall, No. (%) | 45012 | 45012 | ||
| Severe CHD, No. (%) | 355 (50) | 355 (50) | ||
| Age, median (IQR), yr | 0.4 (0.1–1.4) | 0.3 (0.2–0.7) | 0.40 | 0.10 |
| Male | 200 (56.3) | 187 (52.7) | 0.33 | 0.07 |
| Race | 0.02 | 0.06 | ||
| NHW | 194 (54.7) | 215 (60.6) | ||
| NHB | 57 (16.1) | 33 (9.3) | ||
| Other | 104 (29.3) | 107 (30.1) | ||
| Year of surgery | 0.85 | 0.003 | ||
| 2013 | 105 (29.6) | 102 (28.7) | ||
| 2014 | 104 (29.3) | 111 (31.3) | ||
| 2015 | 146 (41.1) | 142 (40.0) | ||
| ASA | 0.99 | 0.01 | ||
| 1 | 0 (0.0) | 0 (0.0) | ||
| 2 | 22 (6.2) | 21 (5.9) | ||
| 3 | 196 (55.2) | 196 (55.2) | ||
| 4 | 136 (38.3) | 138 (38.9) | ||
| 5 | 1 (0.3) | 0 (0.0) | ||
| Elective surgery | 316 (89.0) | 310 (87.3) | 0.49 | 0.05 |
| Weight at surgery, median (IQR), kg | 5.4 (3.7–9.7) | 4.5 (3.6–7.5) | 0.09 | 0.10 |
| Prematurity (<37wks) | 0.06 | 0.19 | ||
| None | 290 (81.7) | 305 (85.9) | ||
| 31–36wks | 46 (13.0) | 44 (12.4) | ||
| 25–30wks | 8 (2.3) | 3 (0.9) | ||
| <25wks | 1 (0.3) | 1 (0.3) | ||
| Unknown | 10 (2.8) | 2 (0.6) | ||
| Inotrope-dependence | 15 (4.2) | 14 (3.9) | 0.85 | 0.01 |
| Chronic lung disease | 41 (11.6) | 27 (7.6) | 0.07 | 0.13 |
| Vent-dependence | 39 (11.0) | 41 (11.6) | 0.81 | 0.02 |
| No. of simult. procs | 0.08 | 0.02 | ||
| 1 | 222 (62.5) | 212 (59.7) | ||
| 2 | 123 (34.7) | 140 (39.4) | ||
| 3+ | 10 (2.8) | 3 (0.9) | ||
| Major CHD, No. (%) | 1579 (50) | 1579 (50) | ||
| Age, median (IQR), yr | 0.5 (0.2–1.3) | 0.4 (0.2–0.9) | 0.001 | 0.13 |
| Male | 823 (52.1) | 848 (53.7) | 0.37 | 0.03 |
| Race | 0.01 | |||
| NHW | 848 (53.7) | 859 (54.4) | ||
| NHB | 273 (17.3) | 236 (15.0) | ||
| Other | 458 (29.0) | 484 (30.7) | ||
| Year of surgery | 0.05 | 0.04 | ||
| 2013 | 382 (24.2) | 334 (21.2) | ||
| 2014 | 473 (30.0) | 524 (33.2) | ||
| 2015 | 724 (45.9) | 721 (45.7) | ||
| ASA | 0.22 | 0.003 | ||
| 1 | 11 (0.7) | 3 (0.2) | ||
| 2 | 191 (12.1) | 193 (12.2) | ||
| 3 | 1034 (65.5) | 1056 (66.9) | ||
| 4 | 341 (21.6) | 326 (20.7) | ||
| 5 | 2 (0.1) | 1 (0.1) | ||
| Elective surgery | 1348 (85.4) | 1338 (84.7) | 0.62 | 0.02 |
| Weight at surgery, median (IQR), kg | 5.3 (3.7–9.3) | 5.1 (3.6–7.8) | 0.004 | 0.13 |
| Prematurity (<37wks) | 0.11 | 0.08 | ||
| None | 942 (59.7) | 1004 (63.6) | ||
| 31–36wks | 302 (19.1) | 274 (17.4) | ||
| 25–30wks | 192 (12.2) | 181 (11.5) | ||
| <25wks | 87 (5.5) | 83 (5.3) | ||
| Unknown | 56 (3.6) | 37 (2.3) | ||
| Inotrope-dependence | 34 (2.2) | 25 (1.6) | 0.24 | 0.04 |
| Chronic lung disease | 405 (25.7) | 392 (24.8) | 0.59 | 0.02 |
| Vent-dependence | 261 (16.5) | 257 (16.3) | 0.85 | 0.01 |
| No. of simult. procs | 0.60 | 0.03 | ||
| 1 | 901 (57.1) | 929 (58.8) | ||
| 2 | 611 (38.7) | 586 (37.1) | ||
| 3+ | 67 (4.2) | 64 (4.1) | ||
| Minor CHD, No. (%) | 1843 (50) | 1843 (50) | ||
| Age, median (IQR), yr | 0.6 (0.2–4.3) | 0.5 (0.2–2.4) | 0.01 | 0.15 |
| Male | 1046 (56.8) | 1097 (59.5) | 0.09 | 0.06 |
| Race | 0.001 | 0.06 | ||
| NHW | 1001 (54.3) | 1089 (59.1) | ||
| NHB | 339 (18.4) | 264 (14.3) | ||
| Other | 503 (27.3) | 490 (26.6) | ||
| Year of surgery | 0.66 | 0.03 | ||
| 2013 | 460 (25.0) | 484 (26.3) | ||
| 2014 | 539 (29.3) | 531 (28.8) | ||
| 2015 | 844 (45.8) | 828 (44.9) | ||
| ASA | 0.003 | 0.07 | ||
| 1 | 53 (2.9) | 47 (2.6) | ||
| 2 | 484 (26.3) | 397 (21.5) | ||
| 3 | 1131 (61.4) | 1243 (67.4) | ||
| 4 | 172 (9.3) | 153 (8.3) | ||
| 5 | 3 (0.2) | 3 (0.2) | ||
| Elective surgery | 1484 (80.5) | 1463 (79.4) | 0.39 | 0.03 |
| Weight at surgery, median (IQR), kg | 6.3 (4.0–15.0) | 5.6 (3.9–11.4) | 0.003 | 0.19 |
| Prematurity (<37wks) | <0.001 | 0.13 | ||
| None | 1014 (55.0) | 1108 (60.1) | ||
| 31–36wks | 321 (17.4) | 311 (16.9) | ||
| 25–30wks | 320 (17.4) | 285 (15.5) | ||
| <25wks | 121 (6.6) | 111 (6.0) | ||
| Unknown | 67 (3.6) | 28 (1.5) | ||
| Inotrope-dependence | 11 (0.6) | 7 (0.4) | 0.48 | 0.03 |
| Chronic lung disease | 488 (26.5) | 457 (24.8) | 0.24 | 0.04 |
| Vent-dependence | 176 (9.6) | 156 (8.5) | 0.25 | 0.04 |
| No. of simult. procs | 0.93 | 0.01 | ||
| 1 | 1163 (63.1) | 1172 (63.6) | ||
| 2 | 618 (33.5) | 612 (33.2) | ||
| 3+ | 62 (3.4) | 59 (3.2) | ||
| No CHD, No. (%) | 41235 (50) | 41235 (50) | ||
| Age, median (IQR), yr | 10.2 (4.8–14.1) | 9.9 (4.4–13.8) | <0.001 | 0.05 |
| Male | 23636 (57.3) | 24000 (58.2) | 0.01 | 0.02 |
| Race | 0.12 | 0.003 | ||
| NHW | 23933 (58.0) | 24073 (58.4) | ||
| NHB | 4577 (11.1) | 4393 (10.7) | ||
| Other | 12725 (30.9) | 12769 (31.0) | ||
| Year of surgery | 0.64 | 0.01 | ||
| 2013 | 11862 (28.8) | 11963 (29.0) | ||
| 2014 | 12489 (30.3) | 12512 (30.3) | ||
| 2015 | 16884 (41.0) | 16760 (40.7) | ||
| ASA | 0.36 | 0.01 | ||
| 1 | 14519 (35.2) | 14267 (34.6) | ||
| 2 | 19839 (48.1) | 20036 (48.6) | ||
| 3 | 6509 (15.8) | 6586 (16.0) | ||
| 4 | 363 (0.9) | 341 (0.8) | ||
| 5 | 5 (0.01 | 5 (0.01) | ||
| Elective surgery | 16780 (40.7) | 16361 (39.7) | 0.003 | 0.02 |
| Weight at surgery, median (IQR), kg | 35.6 (17.7–56.5) | 33.9 (16.6–55.3) | <0.001 | 0.06 |
| Prematurity (<37wks) | 0.03 | 0.02 | ||
| None | 31204 (75.7) | 31602 (76.6) | ||
| 31–36wks | 2072 (5.0) | 2018 (4.9) | ||
| 25–30wks | 589 (1.4) | 559 (1.4) | ||
| <25wks | 113 (0.3) | 102 (0.3) | ||
| Unknown | 7257 (17.6) | 6954 (16.9) | ||
| Inotrope-dependence | 57 (0.1) | 47 (0.1) | 0.33 | 0.01 |
| Chronic lung disease | 583 (1.4) | 525 (1.3) | 0.08 | 0.01 |
| Vent-dependence | 330 (0.8) | 294 (0.7) | 0.15 | 0.01 |
| No. of simult. procs | 0.29 | 0.01 | ||
| 1 | 35936 (87.2) | 36086 (87.5) | ||
| 2 | 5110 (12.4) | 4969 (12.1) | ||
| 3+ | 189 (0.5) | 180 (0.4) |
Values are No. (%) unless otherwise specified.
ASA = American Society of Anesthesiologists physical status; CHD = congenital heart disease; NHW = non-Hispanic whites; NHB = non-Hispanic blacks; SMD = standardized mean difference.
The results of the primary and secondary outcome analyses are shown in Tables 3 and 4. Among children without CHD, laparoscopic surgery was not associated with mortality, but was associated with lower 30-day morbidity (Odds Ratio [OR] 0.88 [95% Confidence Interval (CI) 0.83–0.93]). Among children with minor CHD, laparoscopic surgery was associated with lower odds of 30-day mortality (OR 0.34 [95% CI 0.15–0.79]), in-hospital mortality (OR 0.42 [95% CI 0.22–0.81]), and 30-day morbidity (OR 0.61 [95% CI 0.50–0.73]) than open surgery. As CHD severity increased to major and severe CHD strata, this relative benefit of laparoscopic surgery decreased for 30-day morbidity (ptrend=0.01) and in-hospital mortality (ptrend=0.05) but not for 30-day mortality (ptrend=0.27). Postoperative LOS was shorter following laparoscopic compared to open surgery across all CHD groups (Table 4). Larger differences in LOS were seen across increasing CHD severity groups, although the difference was not statistically significant for the minor CHD group.
Table 3.
Mortality and morbidity across CHD severity, stratified by outcome.
| Outcome | Lap events No. (%) |
Open events No. (%) |
Odds Ratio (lap vs open) | 95% CI | p for trend* |
|---|---|---|---|---|---|
| 30-day mortality | 0.27 | ||||
| Severe CHD | 8 (2.3) | 10 (2.8) | 0.75 | 0.26–2.16 | |
| Major CHD | 21 (1.3) | 26 (1.7) | 0.77 | 0.41–1.45 | |
| Minor CHD | 12 (0.7) | 25 (1.4) | 0.34 | 0.15–0.79 | |
| No CHD | 34 (0.1) | 35 (0.1) | 0.97 | 0.58–1.62 | |
| In-hospital mortality | 0.05 | ||||
| Severe CHD | 13 (3.7) | 10 (2.8) | 1.39 | 0.55–3.51 | |
| Major CHD | 35 (2.2) | 35 (2.2) | 1.00 | 0.59–1.68 | |
| Minor CHD | 20 (1.1) | 37 (2.0) | 0.42 | 0.22–0.81 | |
| No CHD | 57 (0.1) | 55 (0.1) | 1.04 | 0.69–1.57 | |
| 30-day morbidity | 0.01 | ||||
| Severe CHD | 108 (30.4) | 119 (33.5) | 0.82 | 0.57–1.19 | |
| Major CHD | 398 (25.2) | 419 (26.5) | 0.91 | 0.76–1.10 | |
| Minor CHD | 355 (19.3) | 470 (25.5) | 0.61 | 0.50–0.73 | |
| No CHD | 3359 (8.2) | 3674 (8.9) | 0.88 | 0.83–0.93 |
CHD = congenital heart disease; CI = confidence interval; lap = laparoscopic
p for trend from likelihood ratio test across patients with CHD (minor, major, severe).
Table 4.
Postoperative length-of-stay, stratified by CHD severity.
| Outcome | Lap | Open | Beta-coefficient (lap vs open) | 95% CI | p |
|---|---|---|---|---|---|
| Severe CHD (n=621, 87%) | |||||
| LOS, median (IQR), days | 5 (2–11) | 7 (3–15) | −3.6 | −6.0–(−1.2) | 0.004 |
| Major CHD (n=2679, 84%) | |||||
| LOS, median (IQR), days | 5 (2–12) | 6 (3–16) | −2.0 | −3.0–(−1.0) | <0.001 |
| Minor CHD (n=3252, 88%) | |||||
| LOS, median (IQR), days | 3 (1–8) | 4 (1–9) | −0.8 | −1.5–0.01 | 0.05 |
| No CHD (n=81929, 99%) | |||||
| LOS, median (IQR), days | 1 (1–3) | 1 (1–3) | −0.4 | −0.5–(−0.3) | <0.001 |
CHD = congenital heart disease; CI = confidence interval; IQR = interquartile range; lap = laparoscopic; LOS = length of stay
For the subgroup analysis, the magnitude of the association between laparoscopic surgery and higher unplanned readmissions increased across worsening CHD severity groups (ptrend=0.02; Table 5). Laparoscopic surgery was associated with lower odds of transfusion and SSI in nearly all CHD groups, with no significant trends across CHD severity groups. No trends across CHD groups were observed between laparoscopic surgery and either reintubation or MI, though lower odds of reintubation were associated with laparoscopic surgery in children without CHD. Infants ≤1-year-old constituted 15, 60, 73, and 75% of the none, mild, major, and severe CHD groups, respectively. The mortality and morbidity results did not change substantially when assessing only infants (Table 5), only gastrostomy patients (Appendix Table A.5.), or only single procedures (Appendix Table A.6.). When converted cases were reclassified as open instead of laparoscopic, point estimates of odds ratios for morbidity and mortality were similar to our primary analysis, but trends across CHD severity groups were no longer significant (Appendix Table A.7.).
Table 5.
Subgroup analyses across CHD severity, stratified by outcome.
| Outcome | Lap events No. (%) |
Open events No. (%) |
Odds Ratio (lap vs open) | 95% CI | p for trend* |
|---|---|---|---|---|---|
| Readmission | 0.02 | ||||
| Severe CHD | 49 (13.8) | 37 (10.4) | 1.45 | 0.89–2.38 | |
| Major CHD | 169 (10.7) | 100 (6.3) | 2.00 | 1.50–2.67 | |
| Minor CHD | 181 (9.8) | 162 (8.8) | 1.17 | 0.91–1.50 | |
| No CHD | 1955 (4.7) | 1886 (4.6) | 1.05 | 0.98–1.13 | |
| Transfusion | 0.37 | ||||
| Severe CHD | 29 (8.2) | 53 (14.9) | 0.34 | 0.19–0.64 | |
| Major CHD | 78 (4.9) | 122 (7.7) | 0.54 | 0.38–0.75 | |
| Minor CHD | 64 (3.5) | 111 (6.0) | 0.41 | 0.28–0.61 | |
| No CHD | 64 (3.5) | 111 (6.0) | 0.55 | 0.46–0.66 | |
| Reintubation | 0.47 | ||||
| Severe CHD | 23 (6.5) | 27 (7.6) | 0.80 | 0.41–1.55 | |
| Major CHD | 63 (4.0) | 60 (3.8) | 1.07 | 0.72–1.57 | |
| Minor CHD | 35 (1.9) | 45 (2.4) | 0.73 | 0.45–1.20 | |
| No CHD | 35 (1.9) | 45 (2.4) | 0.49 | 0.35–0.69 | |
| MI | 0.81 | ||||
| Severe CHD | 10 (2.8) | 7 (2.0) | 1.53 | 0.53–4.40 | |
| Major CHD | 20 (1.3) | 19 (1.2) | 1.06 | 0.54–2.09 | |
| Minor CHD | 11 (0.6) | 11 (0.6) | 1.00 | 0.40–2.52 | |
| No CHD | 13 (0.03) | 18 (0.04) | 0.67 | 0.31–1.48 | |
| SSI | 0.09 | ||||
| Severe CHD | 10 (2.8) | 16 (4.5) | 0.53 | 0.21–1.33 | |
| Major CHD | 50 (3.2) | 120 (7.6) | 0.28 | 0.19–0.42 | |
| Minor CHD | 56 (3.0) | 91 (4.9) | 0.51 | 0.34–0.76 | |
| No CHD | 1244 (3.0) | 1442 (3.5) | 0.82 | 0.75–0.89 | |
| INFANTS¶ | |||||
| 30-day mortality | 0.50 | ||||
| Severe CHD | 8 (3.2) | 10 (3.5) | 0.85 | 0.29–2.48 | |
| Major CHD | 20 (1.8) | 26 (2.1) | 0.71 | 0.35–1.43 | |
| Minor CHD | 11 (1.0) | 20 (1.8) | 0.39 | 0.14–1.03 | |
| No CHD | 19 (0.3) | 22 (0.4) | 1.10 | 0.50–2.39 | |
| In-hospital mortality | 0.13 | ||||
| Severe CHD | 13 (5.2) | 10 (3.5) | 1.33 | 0.49–3.61 | |
| Major CHD | 33 (3.0) | 34 (2.8) | 1.10 | 0.62–1.96 | |
| Minor CHD | 17 (1.6) | 32 (2.8) | 0.47 | 0.22–0.99 | |
| No CHD | 28 (0.5) | 36 (0.6) | 0.76 | 0.39–1.45 | |
| 30-day morbidity | 0.08 | ||||
| Severe CHD | 97 (38.8) | 110 (38.3) | 0.97 | 0.63–1.51 | |
| Major CHD | 315 (28.4) | 347 (28.6) | 0.92 | 0.74–1.14 | |
| Minor CHD | 232 (21.3) | 318 (28.2) | 0.64 | 0.50–0.83 | |
| No CHD | 560 (9.3) | 661 (10.4) | 0.96 | 0.82–1.12 | |
CHD = congenital heart disease; CI = confidence interval; lap = laparoscopic; MI = myocardial infarction; SSI = surgical site infection
p for trend from likelihood ratio test across patients with CHD (minor, major, severe).
Infants ≤1-year-old constituted 15, 60, 73, and 75% of the non-, mild, major, and severe CHD groups, respectively.
4. Discussion
In this cohort study of 45,012 matched pairs of children undergoing intra-abdominal surgery, we found that severity of CHD is an important determinant of postoperative mortality and morbidity following laparoscopic or open surgery. Laparoscopic surgery was associated with lower 30-day mortality, in-hospital mortality, and 30-day morbidity in children with minor CHD. These benefits were attenuated or absent among children with major or severe CHD. In none of the primary analyses was laparoscopic surgery associated with worse outcomes than open surgery. Rather, these results indicate that although some of the benefits of laparoscopic surgery are lost among children with increasing CHD severity, other specific advantages are maintained. These findings have important implications for joint decision-making and optimizing the safety of children with CHD who require intra-abdominal surgery.
Our study has several strengths that differentiate it from prior studies that examined the association between laparoscopic surgery and clinical outcomes. First, we included children of all ages who underwent surgery at hospitals throughout the United States. One previous study that found fewer complications and lower LOS with comparable 30-day mortality for laparoscopic versus open surgery included only infants <1 year of age; the relative effects are unknown in older children [16]. Second, we assessed a large, contemporary cohort undergoing 46 different operations with different severity of CHD. Several other small case series analyzed their single-institution records to show the safety of laparoscopic surgery, but these were limited by low sample size, specific type of CHD (e.g., hypoplastic left heart syndrome), or analysis of a single procedure (e.g., laparoscopic fundoplication) [14, 15, 17, 18]. By considering multiple intra-abdominal operations simultaneously, we could assess the safety of laparoscopic surgery in a broader context. Third, we used multivariate matching to adjust for multiple potential measured confounders and therefore provide a less biased estimate of the association between laparoscopic surgery and post-operative mortality and morbidity. Fourth, we performed several subgroup and sensitivity analyses to assess the robustness of our findings.
A possible explanation for our primary findings is the different physiologic stress that open surgery and laparoscopic surgery have on children with CHD [29, 30]. Though the stress from laparoscopic surgery is likely less compared to open surgery, the pneumoperitoneum required for intra-abdominal laparoscopic surgery may mitigate the benefit achieved from smaller incisions among children with CHD. Among healthy children, this increased intra-abdominal pressure (10–20mmHg) has been shown to reduce cardiac output, increase peripheral vascular resistance, increase peak airway pressures required for proper ventilation, and decrease end-tidal lung volumes for given pressures needed for ventilation [10–13]. Among healthy children, these physiologic changes are reversed once the abdomen is desufflated. However, for children with CHD, the severity and duration of physiologic effects from pneumoperitoneum remain unknown. In our study, the mortality risk difference between laparoscopic and open surgery was driven more by increases in mortality in the laparoscopy group rather than decreases in mortality in the open group. Thirty-day mortality rates across minor, major, and severe CHD groups rose from 1.4 to 1.7 to 2.8% for open surgery, whereas they rose from 0.7% to 1.3% to 2.3%, respectively, for laparoscopic surgery. These results suggest that a patient’s severity of CHD may be related to his or her vulnerability to changes induced by laparoscopy. However, because hemodynamic and pulmonary measures during and after surgery are not recorded in NSQIP-P, this hypothesis remains speculative and warrants prospective study. It is possible that severe CHD simply becomes the driver of postoperative mortality, regardless of surgical approach.
We also demonstrated, as expected, that LOS increased as CHD severity increased, suggesting that the underlying heart disease influences duration of hospitalization after surgery. Within each CHD severity group, even the severe CHD group, we found that laparoscopic surgery was associated with shorter LOS compared to open surgery. However, an association was also found between laparoscopic surgery and more unplanned readmissions, which increased significantly across CHD severity groups (Table 5). This finding emphasizes the tension between LOS and readmissions as quality metrics seen in surgery [31] and impacts patient counseling. Second, laparoscopic surgery was associated with lower odds of blood transfusion within 72 hours of the procedure compared to open surgery for all children. This lower risk of transfusion has implications on patient outcomes, as transfusion is independently associated with an increased incidence of 30-day mortality and postoperative infections in children undergoing non-cardiac surgery [32]. Since transfusion is innately tied to intraoperative blood loss, laparoscopy should be considered to be associated with less blood loss, although this was not directly measured in NSQIP-P. Third, there was weak evidence that laparoscopic surgery was associated with lower odds of SSI compared to open surgery, especially in the major, minor, and no CHD categories. This is noteworthy given that published risk calculators for SSI using NSQIP-P do not currently incorporate laparoscopic versus open approach [33]. Taken altogether, along with our primary findings, laparoscopic surgery has advantages over open surgery in some, but not all, clinically meaningful surgical outcomes, which importantly appear to be modified by underlying heart disease.
Our study must be interpreted in light of certain limitations. First, as with all observational studies, unmeasured confounding, misclassification of covariates, and bias are possible. One specific example is lack of information on whether a patient had a prior ostomy creation, which could direct whether a procedure is started open or laparoscopic. However, we used multivariate matching to balance the cohorts and performed several subgroup and sensitivity analyses with similar general findings. NSQIP-P also has stringent data measurement and collection to increase validity and reliability. Second, NSQIP-P lacks hospital- and surgeon-level information, which precludes assessment and comparison of hospital and surgeon quality indicators that have been strongly associated with outcomes, including surgical volume [34, 35], surgical subspecialization [36], and nursing quality [37]. Individual surgeon experience with a certain approach is also important to surgical outcomes. Additionally, inter-hospital variation in quality of care is known to influence mortality outcomes [38]. However, the goal of this study was not to identify variation among hospitals or providers nor the processes that might contribute to inter-hospital differences. Third, the laparoscopic indicator variable could not distinguish between pure laparoscopic versus robotic-assisted laparoscopic operations. However, the physiologic effects and anatomic approach are the same. Fourth, concurrent procedures may vary broadly in severity and complexity, which may affect outcomes. However, the results from sensitivity analysis restricted to single procedures were similar to those of our primary analyses. Lastly, as we restricted our analysis to intra-abdominal procedures, our results may not be generalizable to other procedures that can be done by open or laparoscopic means, such as lobectomy. However, including only intra-abdominal procedures increased the internal validity of our study. Additionally, given the heterogeneity of patients in our study, our results are likely broadly applicable.
5. Conclusions
Intra-abdominal laparoscopic surgery may be the safer approach in children with minor CHD, but appears comparable to open surgery in those with more severe disease. Benefits in specific outcomes such as transfusion and LOS following laparoscopy must be balanced against disadvantages such as readmissions. Future prospective studies are warranted to validate these findings and elucidate more detailed cardiopulmonary changes associated with laparoscopic surgery to ensure the optimal care of these children.
Acknowledgments
Funding Source: This work was supported by the National Institutes of Health (NIH)/National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (T32-DK007785-14 and K23-DK106428). The NIH and NIDDK had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript. The views expressed in this article are those of the authors and do not necessarily represent the official view of the NIH nor NIDDK.
Abbreviations
- ASA
American Society of Anesthesiologists
- CHD
congenital heart disease
- CI
confidence interval
- CPT
common procedural terminology
- LOS
length of stay
- MI
myocardial infarction
- NHB
non-Hispanic Black
- NHW
non-Hispanic White
- NSQIP-P
National Surgical Quality Improvement Program – Pediatrics
- OR
odds ratio
- SMD
standardized mean difference
- SSI
surgical site infection
Appendix A
Table A.1.
Common Procedural Terminology codes for included and matched surgical procedures.
| Lap CPT | Laparoscopic procedure | Open CPT | Open procedure |
|---|---|---|---|
| 43653 | Lap gastrostomy | 43830 | Gastrostomy |
| 43832 | |||
| 43279 | Lap fundoplasty | 43325 | Fundoplasty |
| 43280 | 43327 | ||
| 43328 | |||
| 44970 | Lap appendectomy | 44950 | Appendectomy |
| 44960 | |||
| 54692 | Lap orchiopexy | 54650 | Orchiopexy (intra-abdominal) |
| 47562 | Lap cholecystectomy | 47600 | Cholecystectomy |
| 47563 | 47605 | ||
| 47564 | 47610 | ||
| 47612 | |||
| 47620 | |||
| 50947 | Lap ureteroneocystostomy | 50780 | Ureteroneocystostomy |
| 50948 | 50782 | ||
| 50783 | |||
| 44186 | Lap ileostomy/jejunostomy | 44310 | Ileostomy/jejunostomy |
| 44187 | |||
| 44180 | Lap enterolysis | 44005 | Enterolysis |
| 44188 | Lap colostomy | 44320 | Colostomy |
| 45395 | Lap proctectomy | 45112 | Proctectomy |
| 45397 | 45119 | ||
| 45120 | |||
| 50544 | Lap pyeloplasty | 50400 | Pyeloplasty |
| 50405 | |||
| 45400 | Lap proctopexy | 45540 | Proctopexy |
| 45402 | 45541 | ||
| 45550 | |||
| 58661 | Lap salpingo-oophorectomy | 58720 | Salpingo-oophorectomy |
| 58940 | |||
| 58943 | |||
| 58950 | |||
| 58952 | |||
| 38120 | Lap splenectomy | 38100 | Splenectomy |
| 38101 | |||
| 43281 | Lap repair of paraesophageal hernia without mesh | 43332 | Repair of paraesophageal hernia without mesh |
| 43334 | |||
| 43336 | |||
| 43282 | Lap repair of paraesophageal hernia with mesh | 43333 | Repair of paraesophageal hernia with mesh |
| 43335 | |||
| 43337 | |||
| 50543 | Lap partial nephrectomy | 50240 | Partial nephrectomy |
| 50545 | Lap nephrectomy | 50220 | Nephrectomy |
| 50546 | 50225 | ||
| 50548 | 50230 | ||
| 50234 | |||
| 50236 | |||
| 44204 | Lap partial colectomy | 44140 | Partial colectomy |
| 44205 | 44141 | ||
| 44206 | 44143 | ||
| 44207 | 44144 | ||
| 44208 | 44145 | ||
| 44147 | |||
| 44160 | |||
| 44202 | Lap enterectomy | 44120 | Enterectomy |
| 44121 | |||
| 44125 | |||
| 44126 | |||
| 44128 | |||
| 44130 | |||
| 44210 | Lap total colectomy | 44155 | Total colectomy |
| 44211 | 44156 | ||
| 44212 | 44157 | ||
| 44158 | |||
| 49324 | Lap insertion of intraperitoneal catheter | 49421 | Insertion of peritoneal dialysis catheter |
| 55550 | Lap varicocelectomy | 55530 | Varicocelectomy |
| 43644 | Lap gastric bypass | 43845 | Gastric bypass |
| 43645 | 43846 | ||
| 43770 | Lap gastric band | 43842 | Gastric band |
| 43771 | |||
| 43773 | |||
| 58541 | Lap hysterectomy | 58150 | Hysterectomy |
| 58542 | 58180 | ||
| 38570 | Lap RPLND | 38564 | RPLND |
| 38572 | 38747 | ||
| 38765 | |||
| 38770 | |||
| 38780 | |||
| 44227 | Lap closure of enterostomy | 44620 | Closure of enterostomy |
| 44625 | |||
| 44626 | |||
| 62225 | Replacement CSF shunt | ||
| 62230 | |||
| 62223 | Creation VP shunt | ||
| 62220 | Creation VA shunt | ||
| 62258 | Removal of CSF shunt | ||
| 43520 | Pyloromyotomy | ||
| 50760 | Ureteroureterostomy | ||
| 50830 | Urinary undiversion | ||
| 39503 | Neonatal diaphragmatic hernia repair | ||
| 39541 | Diaphragmatic hernia repair (non-neonatal) | ||
| 44050 | Reduction of volvulus, intussusception, internal hernia | ||
| 51500 | Excision of urachal remnant | ||
| 44346 | Revision of colostomy with repair of para-colostomy hernia | ||
| 44660 | Closure of enterovesical fistula without GI/bladder resection | ||
| 44661 | Closure of enterovesical fistula with GI/bladder resection | ||
| 44650 | Closure of enteroenteric or enterocolic fistula | ||
| 44615 | Intestinal stricturoplasty | ||
| 44300 | Enterostomy/cecostomy tube placement | ||
| 51960 | Enterocystoplasty |
CPT = common procedural terminology; lap = laparoscopic; RPLND = retroperitoneal lymph node dissection; VA = ventriculoatrial; VP = ventriculoperitoneal; CSF = cerebrospinal fluid
Table A.2.
NSQIP-P definition and classification of CHD severity.
| Classification | Definition and Criteria |
|---|---|
| Minor CHD |
|
| Major CHD |
|
| Severe CHD |
|
NSQIP-P = National Surgical Quality Improvement Program Pediatrics version; CHD = congenital heart disease
Table A.3.
Most common surgical procedures and frequencies after matching, by CHD severity.
| Procedure | No. |
|---|---|
| Severe CHD (355 matched pairs) | |
| Gastrostomy | 360 |
| Fundoplication | 202 |
| Appendectomy | 44 |
| Intra-abdominal orchiopexy | 32 |
| Cholecystectomy | 28 |
| Major CHD (1579 matched pairs) | |
| Gastrostomy | 1414 |
| Fundoplication | 766 |
| Appendectomy | 172 |
| Intra-abdominal orchiopexy | 134 |
| Neonatal diaphragmatic hernia repair | 116 |
| Minor CHD (1843 matched pairs) | |
| Gastrostomy | 1506 |
| Fundoplication | 752 |
| Appendectomy | 348 |
| Pyloromyotomy | 168 |
| Cholecystectomy | 142 |
| No CHD (41235 matched pairs) | |
| Appendectomy | 46134 |
| Cholecystectomy | 8272 |
| Pyloromyotomy | 6028 |
| Gastrostomy | 5494 |
| Fundoplication | 2648 |
CHD = congenital heart disease
Table A.4.
Frequencies of outcomes in matched cohort, stratified by CHD severity.
| Variable | No CHD | Minor CHD | Major CHD | Severe CHD |
|---|---|---|---|---|
| Total No. (%) | 82470 (91.6) | 3686 (4.1) | 3158 (3.5) | 710 (0.8) |
| 30-day mortality | 69 (0.1) | 37 (1.0) | 47 (1.5) | 18 (2.5) |
| In-hospital mortality | 112 (0.1) | 57 (1.6) | 70 (2.2) | 23 (3.2) |
| 30-day morbidity | 7033 (8.5) | 825 (22.4) | 817 (25.9) | 227 (32.0) |
| Reintubation | 195 (0.2) | 80 (2.2) | 123 (3.9) | 50 (7.0) |
| MI | 31 (0.04) | 22 (0.6) | 39 (1.2) | 17 (2.4) |
| Transfusion | 669 (0.8) | 175 (4.8) | 200 (6.3) | 82 (11.6) |
| SSI | 2686 (3.3) | 147 (4.0) | 170 (5.4) | 26 (3.7) |
| UTI | 268 (0.3) | 28 (0.8) | 29 (0.9) | 2 (0.3) |
| CLABSI | 43 (0.1) | 11 (0.3) | 18 (0.6) | 4 (0.6) |
| Pneumonia | 206 (0.3) | 84 (2.3) | 95 (3.0) | 9 (1.3) |
| Sepsis | 409 (0.5) | 45 (1.2) | 68 (2.2) | 11 (1.6) |
| VTE | 48 (0.1) | 5 (0.1) | 8 (0.3) | 8 (1.1) |
| Neurologic sequelae | 59 (0.1) | 24 (0.7) | 24 (0.8) | 5 (0.7) |
| Unplanned reoperation | 1511 (1.8) | 176 (4.8) | 188 (6.0) | 57 (8.0) |
| Unplanned readmission | 3841 (4.7) | 343 (9.3) | 269 (8.5) | 86 (12.1) |
Numbers are no. (%). CHD = congenital heart disease; MI = myocardial infarction; SSI = surgical site infection; UTI = urinary tract infection; CLABSI = central-line-associated bloodstream infection; VTE = venothrombotic event
Table A.5.
Procedure-specific (gastrostomy) subgroup analysis across CHD severity, stratified by outcome.
| Outcome | Lap | Open | OR | 95% CI | p for trend* |
|---|---|---|---|---|---|
| 30-day mortality | 0.67 | ||||
| Severe CHD | 4 (2.2) | 8 (4.4) | 0.38 | 0.09–1.57 | |
| Major CHD | 11 (1.6) | 13 (1.8) | 0.80 | 0.32–2.02 | |
| Minor CHD | 6 (0.8) | 9 (1.2) | 0.58 | 0.17–1.93 | |
| No CHD | 14 (0.5) | 13 (0.5) | 1.09 | 0.48–2.50 | |
| In-hospital mortality | 0.07 | ||||
| Severe CHD | 5 (2.8) | 8 (4.4) | 0.53 | 0.14–1.95 | |
| Major CHD | 18 (2.6) | 14 (2.0) | 1.36 | 0.63–2.96 | |
| Minor CHD | 7 (0.9) | 16 (2.1) | 0.31 | 0.11–0.90 | |
| No CHD | 23 (0.8) | 17 (0.6) | 1.44 | 0.72–2.88 | |
| 30-day morbidity | 0.01 | ||||
| Severe CHD | 55 (30.6) | 52 (28.9) | 1.11 | 0.66–1.84 | |
| Major CHD | 165 (23.3) | 176 (24.9) | 0.90 | 0.68–1.18 | |
| Minor CHD | 119 (15.8) | 178 (23.6) | 0.51 | 0.38–0.70 | |
| No CHD | 399 (14.5) | 442 (16.1) | 0.85 | 0.72–1.01 |
CHD = congenital heart disease; CI = confidence interval; lap = laparoscopic
p for trend from likelihood ratio test across patients with CHD (minor, major, severe).
Table A.6.
Sensitivity analysis across CHD severity restricted to single procedures without concurrent procedures, stratified by outcome.
| Outcome | Lap events No. (%) |
Open events No. (%) |
Odds Ratio (lap vs open) | 95% CI | p for trend* |
|---|---|---|---|---|---|
| 30-day mortality | 0.003 | ||||
| Severe CHD | 4 (1.9) | 1 (0.5) | 4.00 | 0.45–35.79 | |
| Major CHD | 14 (1.6) | 19 (2.1) | 0.67 | 0.30–1.48 | |
| Minor CHD | 3 (0.3) | 15 (1.3) | 0.08 | 0.02–0.37 | |
| No CHD | 22 (0.1) | 33 (0.1) | 0.60 | 0.33–1.10 | |
| In-hospital mortality | <0.001 | ||||
| Severe CHD | 8 (3.9) | 1 (0.5) | 8.00 | 1.00–63.96 | |
| Major CHD | 23 (2.6) | 22 (2.5) | 1.06 | 0.54–2.11 | |
| Minor CHD | 6 (0.5) | 21 (1.8) | 0.16 | 0.05–0.48 | |
| No CHD | 36 (0.1) | 56 (0.2) | 0.55 | 0.34–0.90 | |
| 30-day morbidity | 0.007 | ||||
| Severe CHD | 60 (29.1) | 45 (21.8) | 1.55 | 0.96–2.50 | |
| Major CHD | 210 (23.5) | 213 (23.8) | 0.98 | 0.76–1.25 | |
| Minor CHD | 188 (16.3) | 236 (20.4) | 0.69 | 0.54–0.88 | |
| No CHD | 2619 (7.3) | 2788 (7.8) | 0.91 | 0.86–0.97 |
CHD = congenital heart disease; CI = confidence interval; lap = laparoscopic
p for trend from likelihood ratio test across patients with CHD (minor, major, severe).
Table A.7.
Sensitivity analysis across CHD severity where laparoscopic converted to open procedures were reclassified as open, stratified by outcome.
| Outcome | Lap events No. (%) |
Open events No. (%) |
Odds Ratio (lap vs open) | 95% CI | p for trend* |
|---|---|---|---|---|---|
| 30-day mortality | 0.56 | ||||
| Severe CHD | 8 (2.5) | 10 (3.2) | 0.75 | 0.26–2.16 | |
| Major CHD | 17 (1.2) | 24 (1.7) | 0.67 | 0.34–1.31 | |
| Minor CHD | 10 (0.6) | 19 (1.1) | 0.38 | 0.15–0.98 | |
| No CHD | 26 (0.1) | 28 (0.1) | 0.92 | 0.51–1.64 | |
| In-hospital mortality | 0.30 | ||||
| Severe CHD | 12 (3.8) | 10 (3.2) | 1.26 | 0.49–3.25 | |
| Major CHD | 29 (2.1) | 31 (2.2) | 0.92 | 0.53–1.60 | |
| Minor CHD | 17 (1.0) | 27 (1.6) | 0.54 | 0.26–1.09 | |
| No CHD | 46 (0.1) | 41 (0.1) | 1.15 | 0.72–1.82 | |
| 30-day morbidity | 0.39 | ||||
| Severe CHD | 95 (30.1) | 115 (36.4) | 0.68 | 0.47–1.01 | |
| Major CHD | 323 (23.4) | 363 (26.3) | 0.83 | 0.68–1.00 | |
| Minor CHD | 304 (18.3) | 378 (22.8) | 0.69 | 0.57–0.84 | |
| No CHD | 3006 (7.7) | 3397 (8.7) | 0.84 | 0.79–0.89 |
CHD = congenital heart disease; CI = confidence interval; lap = laparoscopic
p for trend from likelihood ratio test across patients with CHD (minor, major, severe).
Footnotes
Data Source: The American College of Surgeons National Surgical Quality Improvement Program and the hospitals participating in the ACS NSQIP are the source of the data used herein; they have not verified and are not responsible for the statistical validity of the data analysis or the conclusions derived by the authors.
Level-of-Evidence:
Level III - Treatment Study
Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
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