A 20-Year Analysis of Risk Factors for Complicated Postoperative Course Following Laparoscopic Cholecystectomy

Abstract

Background

Cholecystectomy is the most common surgical intervention performed in the United States with over 300,000 annual cases. We aim to describe risk factors for complications and prolonged stay after cholecystectomy in a 20-year analysis of a national database.

Methods

The Nationwide Inpatient Sample (NIS) was queried for years 2000-2019 for patients who underwent cholecystectomy within 7 days of admission. Complicated stay was defined as postoperative stay longer than 3 days or an ICU admission. Outcomes were postoperative complications, hospital length of stay, hospital charges, and mortality.

Results

There were 901,205 patients who underwent laparoscopic cholecystectomy. Mean age was 50 ± 19 years, 68% were female. Complicated stay was identified in 13% of patients. These patients were older (61 ± 19 vs 49 ± 19), more likely to be male (47% vs 32%), and to have Medicare insurance (51% vs 26%). Acute presentation as indication for surgery (acute cholecystitis, choledocholithiasis, and pancreatitis) were more common in complicated stays compared to chronic cholecystitis or cholelithiasis only. They were more likely to undergo subtotal cholecystectomy (1.2% vs 0.54%) or conversion to open surgery (0.98% vs 0.08%), to suffer common bile duct injury (0.54% vs 0.04%), and have higher mortality (2.4% vs 0.06%). On multivariate regression, the strongest predictors for complicated stay were CBDI (OR 12.9), conversion to open (OR 11.4), and subtotal cholecystectomy (OR 1.8).

Conclusion

Open or subtotal cholecystectomy, older age, pancreatitis, and delayed operation from admission were associated with complicated course. This data highlights careful preoperative risk stratification and early operative intervention to reduce complications.

Keywords

laparoscopic cholecystectomy cholecystitis biliary pancreatitis subtotal cholecystectomy

Introduction

Gallstones affects approximately 10-15% of adults in the United States. The clinical presentation of gallstone disease varies from asymptomatic cholelithiasis to a range of complications including acute cholecystitis, gallstone pancreatitis, and cholangitis. The introduction of laparoscopic cholecystectomy (LC) reduced postoperative pain, shorter hospital stay, and faster recovery.^1-4 Furthermore, quality metrics for cholecystectomy include increased utilization of an early laparoscopic approach with its association with fewer postoperative complications.^5-7

However, in cases of severe inflammation, fibrosis, or unclear anatomy, or in other conditions such as known carcinoma or uncompensated cirrhosis, there may be relative or absolute contraindications to laparoscopy necessitating alternative approaches. Subtotal cholecystectomy, including its fenestrating and reconstituting subtypes, has emerged as a viable strategy in cases where safe dissection of Calot’s triangle is not possible, providing an alternative to conversion to open cholecystectomy, which is associated with increased morbidity.⁸

With a continued focus on lowering hospital length of stay predictive factors for a complicated postoperative course are important to evaluate.⁹ The recognition of these risk factors is essential for optimizing perioperative management strategies and patient outcomes which is the aim of this 20-year analysis.^5-7

Methods

This study utilized data from the Nationwide Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, covering admissions from 2000 to 2019. The NIS is the largest all-payer inpatient database in the United States, capturing approximately 7 million hospitalizations annually and serving as a representative sample of national trends.

Inpatient stays of adult patients who underwent laparoscopic cholecystectomy within 7 days of admission were identified using International Classification of Disease, 9th and 10th Editions – Clinical Modification (ICD-9-CM and ICD-10-CM) procedure codes. A complicated postoperative course was defined as a hospital stay exceeding 3 days after surgery or an admission to the intensive care unit.

Demographic variables included age, sex, race, and insurance type. The Charlson Comorbidity Index (CCI) was used to assess the burden of comorbidities. Hospital characteristics included location and teaching status. Indications for cholecystectomy were grouped as cholelithiasis without cholecystitis, acute cholecystitis, chronic cholecystitis, choledocholithiasis, pancreatitis, and hospital charges.

Continuous variables were summarized using mean ± standard deviation for normally distributed data and compared with Student’s t-test or ANOVA. Non-normally distributed data were presented as median [interquartile range] and analyzed using the Kruskal-Wallis test. Categorical variables were reported as percentages and compared using Chi-square analysis. Trends over the study period in the demographics, hospital types, and our primary outcome were assessed using bivariate linear regression models. The P-values from these analyses measured the likelihood that linear trends exist in estimates of successive years. Multivariate logistic regression models were developed with stepwise selection to identify independent predictors of a complicated postoperative course, CBDI, and mortality. Variables incorporated into the models included age, gender, race, insurance, CCI, elective admission, hospital type, surgical indication, time to operation, subtotal surgery, conversion to open, and CBDI. Variables were included if they improved the performance of the models measured by the Area Under Receiver Operative Curve (AUROC). Statistical analyses were conducted using Stata Statistical Software: Release 18.0 (StataCorp LLC), with a significance threshold of P < 0.05.

Results

A total of 901,205 hospital stays for patients undergoing laparoscopic cholecystectomy were included in the analysis. The mean patient age was 50 ± 19 years, with 68% being female. The racial distribution included 64% White, 9.4% African American, and 21% Hispanic patients. A complicated postoperative course was observed in 117,161 (13%) of patients. Those with a complicated course were significantly older (61 ± 19 vs 49 ± 19, P < 0.01), more likely to be male (47% vs 32%, P < 0.01), and less likely to be Hispanic (17% vs 21%, P < 0.01). Medicare was the most common insurance in patients with a complicated course (51% vs 26%, P < 0.01).

Over the 20 years analyzed, mean age increased from 49 to 52 years, P < 0.05. Female gender decreased from 73% to 64%, P < 0.05. There was a significant increase in proportion of patients with Medicaid insurance (11.5% in 2000 to 21.6% in 2019), uninsured patients (6.3% to 8%), with a decrease in patients with private insurance (50% to 38%), P < 0.01. The share of patients per hospital type also changes significantly with an increase in patients presenting to urban teaching hospitals (34% in 2000 to 71% in 2019), with a decrease in urban non-teaching (50% to 23%), and rural hospitals (16% to 6.4%), P < 0.01. The proportion of patients who had a complicated course remained stable overall between 12.6 and 13.2%, P = 0.072.

Patients with a complicated postoperative course were more likely to have an acute indication for surgery (Acute Cholecystitis 58% vs 54.1%, Choledocholithiasis 7.5% vs 3%, Pancreatitis 22% vs 18%, P < 0.01) compared to cholelithiasis without cholecystitis (9.4% in complicated vs 10.4%) or Chronic Cholecystitis (47.7% vs 48.4%). They were also more likely to have been admitted electively (19% vs 15%, P < 0.01). They were also more likely to undergo preoperative ERCP (3% vs 2.3%), a subtotal cholecystectomy (1.2% vs 0.54%), a conversion to an open surgery (0.98% vs 0.08%), or a postoperative ERCP (7.1% vs 2.8%), P < 0.01. Common bile duct injury was also higher in this cohort (0.54% vs 0.04%, P < 0.01). These had significantly longer postoperative hospital stays (5 [4-7] vs 1 [1-2] days, P < 0.01), higher hospital charges ($44K [$27K-$74K] vs $25K [$15K-$41K], P < 0.01), and increased mortality (2.4% vs 0.06%, P < 0.01). (Table 1)

Table 1.

Demographics and Outcomes of Patients Undergoing Laparoscopic Cholecystectomy Between 2000 and 2019

	All patients (n = 901,205)	Uncomplicated (n = 784,044)	Complicated (n = 117,161)	P-value
Age	50 ± 19	49 ± 19	61 ± 19	<0.01
Female	585,780 (65%)	533,150 (68%)	62,095 (53%)	<0.01
Race				<0.01
White	573,707 (64%)	496,378 (63%)	77,291 (66%)
African-American	84,945 (9.4%)	72,042 (9.2%)	12,904 (11%)
Hispanic	185,067 (21%)	165,457 (21%)	19,609 (17%)
Other	57,391 (6.4%)	45,600 (6.3%)	7,792 (6.6%)
Charlson index	0 [0-1]	0 [0-1]	1 [0-2]	<0.01
Insurance				<0.01
Medicare	265,556 (30%)	205,335 (26%)	60,221 (51%)
Private	400,309 (44%)	364,117 (47%)	36,192 (31%)
Medicaid	151,750 (17%)	136,816 (18%)	14,934 (13%)
Uninsured	83,507 (9.3%)	76,645 (9.8%)	6862 (5.8%)
Hospital type				<0.01
Rural	100,547 (11%)	87,182 (11%)	13,365 (11%)
Urban non-teaching	410,742 (45%)	355,649 (46%)	55,093 (47%)
Urban teaching	387,892 (43%)	339,466 (43%)	48,426 (41%)
Elective admission	129,634 (16%)	110,251 (16%)	19,383 (19%)	<0.01
Indication for surgery				<0.01
Cholelithiasis	92,610 (10.3%)	81,642 (10.4%)	10,968 (9.4%)
Acute cholecystitis	492,186 (54.6%)	424,287 (54.1%)	67,899 (58%)
Chronic cholecystitis	434,964 (48.3%)	379,057 (48.4%)	55,907 (47.7%)
Choledocholithiasis	32,289 (3.6%)	23,470 (3%)	8819 (7.5%)
Pancreatitis	157,665 (18%)	132,044 (17%)	25,621 (22%)
Hospital day of surgery	1 [0-2]	1 [0-2]	1 [0-3]	<0.01
Preoperative ERCP	21,638 (2.4%)	18,082 (2.3%)	3.556 (3%)	<0.01
Postoperative ERCP	30,234 (3.35%)	21,907 (2.8%)	8327 (7.1%)	<0.01
Subtotal cholecystectomy	5669 (0.63%)	4261 (0.54%)	1408 (1.2%)	<0.01
Converted to open	1748 (0.19%)	601 (0.08%)	1147 (0.98%)	<0.01
Overall complications	56,840 (6.3%)	27,636 (3.5%)	29,204 (25%)	<0.01
CBDI	967 (0.11%)	335 (0.04%)	632 (0.54%)	<0.01
Post-operative LOS	1 [1-2]	1 [1-2]	5 [4-7]	<0.01
Hospital LOS	3 [2-4]	2 [2-4]	7 [5-9]	<0.01
Hospital charges	28K [17K-47 K]	26K [16K-42 K]	49K [30K-80 K]	<0.01
Mortality	2813 (0.31%)	336 (0.04%)	2477 (2.12%)	<0.01

CBDI: Common Bile Duct Injury. LOS: length of stay. ERCP: Endoscopic Retrograde Cholangiopancreatography.

On multivariate regression analysis, the strongest independent predictors of a complicated course were conversion to open cholecystectomy (OR 12.9, 95% CI [11.4-14.7]), CBDI (OR 11.4, 95% CI [9.4-13.8]), and subtotal cholecystectomy (OR 1.8, 95% CI [1.5-2.15]). Independent predictors for CBDI included conversion to open surgery (OR 28.3 [21.3-36.6]), subtotal cholecystectomy (OR 3.2, 95%CI [2.1-4.8]), and an elective admission (OR 2.58, 95% CI [2.17-3.07]). Predictors for mortality included CBDI (OR 6.4, 95% CI [3.5-11.7]), Comorbidity Index (OR 1.5, 95% CI [1.47-1.53]), and non-private insurance. (Table 2)

Table 2.

Adjusted Odds Ratio for Outcomes of Laparoscopic Cholecystectomy on Multivariate Logistic Regression Analysis: (Results Displayed as Odds Ratio [95% Confidence Interval])

	Complicated stay	CBDI	Mortality
Age	1.025 [1.024-1.0253]	NS	1.076 [1.07-1.08]
Female (vs Male)	0.83 [0.81-0.84]	1.18 [1.015-1.38]	0.84 [0.76-0.93]
African American (vs White)	1.41 [1.37-1.45]	-	NS
Hispanic (vs White)	1.07 [1.04-1.09]	-	0.81 [0.69-0.96]
Medicaid (vs Private)	1.39 [1.35-1.43]	NS	1.53 [1.28-1.82]
Medicare (vs Private)	1.27 [1.24-1.3]	NS	2.1 [1.6-2.7]
Uninsured (vs Private)	1.09 [1.06-1.13]	NS	1.57 [1.08-2.27]
Charlson index	1.37 [1.36-1.38]	1.1 [1.04-1.16]	1.5 [1.47-1.54]
Elective admission	1.17 [1.14-1.2]	2.58 [2.17-3.07]	NS
Cholelithiasis w/o cholecystitis	NS	NS	0.55 [0.43-0.71]
Acute cholecystitis	1.27 [1.27-1.31]	1.29 [1.08-1.54]	NS
Chronic cholecystitis	NS	1.38 [1.13-1.67]	0.75 [0.66-0.86]
Choledocholithiasis	2.2 [2.12-2.27]	10.6 [9-12.6]	NS
Pancreatitis	1.34 [1.31-1.37]	NS	0.73 [0.63-0.83]
Hospital day of surgery	1.022 [1.016-1.028]	NS	1.17 [1.14-1.2]
Subtotal cholecystectomy	1.8 [1.5-2.15]	3.2 [2.1-4.8]	NS
Conversion to open	12.9 [11.4-14.7]	28.3 [21.3-36.6]	NS
CBDI	11.4 [9.4-13.8]	-	6.4 [3.5-11.7]
Rural (vs Urban teaching)	NS	NS	1.21 [1.03-1.42]
Urban non-teaching (vs Urban teaching)	1.04 [1.02-1.06]	NS	NS
Area Under curve	0.73	0.73	0.9

CBDI: Common Bile Duct Injury. NS: Not statistically significant.

Discussion

Our study demonstrates that 13% of inpatient stays for patients who underwent laparoscopic cholecystectomies in the US over the past 20 years were associated with a complicated postoperative course with an estimated 546,859 additional days in hospital stay and an estimated additional $3.6 B in hospital charges. This data requires performance improvement processes that focus on early identification and operative planning for high-risk patients. The impact of recruiting advanced technical expertise and preoperative imaging to guide optimal operative approaches must be better understood.

Our analysis highlights subtotal cholecystectomy, conversion to open surgery, CBDI, older age, and the presence of pancreatitis as key predictors of a complicated postoperative course following cholecystectomy. These findings are consistent with prior studies that have emphasized the increased morbidity associated with open and delayed surgical intervention in patients with acute cholecystitis.^10,11 Older age, Medicare, and Medicaid patients represent different cohorts of socioeconomically vulnerable populations who usually have other confounders that are not well captured in an administrative database like mobility issues, social support, access to primary care and preventative medicine or early access. Interestingly, urban teaching hospitals, many of which are safety net hospitals that treat many patients from these cohorts, had better overall outcomes and decreased risk for complicated stay than other hospitals.

The Tokyo Guidelines 2018 provide a standardized framework for diagnosing and grading acute cholecystitis and have been instrumental in guiding clinical management.¹² However, risk stratification remains challenging, particularly in patients with moderate disease (grade II), where surgical difficulty can vary significantly.¹³ Prior research has suggested that factors such as male sex, delayed presentation, and preoperative organ dysfunction contribute to higher rates of conversion to open surgery and increased complications.¹²

The increased proportion of complicated course in patients electively admitted—presumably for delayed cholecystectomy after an acute episode, or for preoperative optimization of high-risk patient—as well as the increased risk associated with performing subtotal cholecystectomy further underscores the complexity of these cases and need for careful preoperative risk assessment. Prior studies have reported comparable complication rates between subtotal and total cholecystectomy, yet our findings suggest that patients needing to undergo partial cholecystectomy are more likely to have a prolonged hospitalization and an intensive care admission.^8,10,11

Pancreatitis was also a significant predictor of complicated postoperative course in our study. Prior research has shown that early cholecystectomy during the same admission reduces the risk of recurrent biliary events and hospitalizations compared to delayed intervention.¹⁴ Our findings highlight both a co-diagnosis of pancreatitis as well as delayed surgery as risk factors for increased complications. Therefore, controversy persists regarding the optimal timing of surgery after biliary pancreatitis, especially cases of moderate and severe pancreatitis, with some studies suggesting that early cholecystectomy may exacerbate systemic inflammation and increase postoperative morbidity.¹⁵ Careful patient selection is prudent in these cases.

This study has several limitations inherent to its retrospective nature utilizing an administrative database, making it prone to confounding due to changes and differences in hospital coding practices. HCUP-NIS includes inpatient stays only which excludes all same day laparoscopic cholecystectomy patients who were not admitted postoperatively from this analysis. The absence of preoperative physiologic data limits our ability to assess the severity of illness and risk stratify patients preoperatively, which could influence the decision to pursue surgery, convert to an open approach, or perform subtotal cholecystectomy. Additionally, the use of 2 different iterations of ICD-CM over the study period may have affected coding accuracy, particularly in differentiating laparoscopic from open interventions. Nevertheless, our findings align with existing literature, and the large sample size provides valuable insights into risk factors for complicated postoperative courses.

Conclusion

Open and subtotal cholecystectomy, older age, pancreatitis, and delayed intervention were associated with a complicated postoperative course. Our results reinforce existing literature supporting early cholecystectomy to reduce complications.

Footnotes

ORCID iDs

Ahmad Zeineddin

Mariana Olivencia-Delgado

Mallory Williams

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

References

Keus

De Jong

JAF

Gooszen

Van Laarhoven

CJHM

. Laparoscopic versus open cholecystectomy for patients with symptomatic cholecystolithiasis. Cochrane Database Syst Rev. 2006;(4). doi:10.1002/14651858.CD006231

Tsang

Poon

Lee

Leong

. Predictive factors of long hospital stay after laparoscopic cholecystectomy. Asian J Surg. 2007;30(1):23-28. doi:10.1016/S1015-9584(09)60123-8

Coccolini

Catena

Pisano

, et al. Open versus laparoscopic cholecystectomy in acute cholecystitis. Systematic review and meta-analysis. Int J Surg. 2015;18:196-204. doi:10.1016/j.ijsu.2015.04.083

Ripetti

Luffarelli

Santoni

Greco

. Laparoscopic cholecystectomy: do risk factors for a prolonged length of stay exist? Updates Surg. 2019;71(3):471-476. doi:10.1007/s13304-019-00641-4

Randall

Chen

Brody

. Cholecystectomy outcomes in the veterans affairs surgical quality improvement program (2006--2017). J Laparoendosc Adv Surg Tech. 2021;31(3):251-260.

Gallaher

Charles

. Acute cholecystitis: a review. JAMA. 2022;327(10):965-975. doi:10.1001/jama.2022.2350

Gutt

Encke

Köninger

, et al. Acute cholecystitis: early versus delayed cholecystectomy, a multicenter randomized trial (ACDC Study, NCT00447304). Ann Surg. 2013;258(3):385-391. doi:10.1097/SLA.0b013e3182a1599b

van Dijk

Donkervoort

Lameris

, et al. Short- and long-term outcomes after a reconstituting and fenestrating subtotal cholecystectomy. J Am Coll Surg. 2017;225(3):371-379. doi:10.1016/j.jamcollsurg.2017.05.016

Chong

Lee

Yoon

, et al. Influencing factors on postoperative hospital stay after laparoscopic cholecystectomy. Korean J Hepatobiliary Pancreat Surg. 2016;20(1):12-16. doi:10.14701/kjhbps.2016.20.1.12

10.

Strasberg

Pucci

Brunt

Deziel

. Subtotal Cholecystectomy-“Fenestrating” vs “reconstituting” subtypes and the prevention of bile duct injury: definition of the optimal procedure in difficult operative conditions. J Am Coll Surg. 2016;222(1):89-96. doi:10.1016/j.jamcollsurg.2015.09.019

11.

Kaplan

Inaba

Chouliaras

, et al. Subtotal cholecystectomy and open total cholecystectomy: alternatives in complicated cholecystitis. Am Surg. 2014;80(10):953-955. doi:10.1177/000313481408001009

12.

Yokoe

Hata

Takada

, et al. Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis (with videos). J Hepatobiliary Pancreat Sci. 2018;25(1):41-54. doi:10.1111/ijlh.12426

13.

Inoue

Ueno

Douchi

, et al. Risk factors for difficulty of laparoscopic cholecystectomy in grade II acute cholecystitis according to the Tokyo guidelines 2013. BMC Surg. 2017;17(1):1-8. doi:10.1186/s12893-017-0319-6

14.

Aboulian

Chan

Yaghoubian

, et al. Early cholecystectomy safely decreases hospital stay in patients with mild gallstone pancreatitis: a randomized prospective study. Ann Surg. 2010;251(4):615-619. doi:10.1097/SLA.0b013e3181c38f1f

15.

Mueck

Wei

Pedroza

, et al. Gallstone pancreatitis: admission versus normal cholecystectomy-A randomized trial (gallstone PANC trial). Ann Surg. 2019;270(3):519-527. doi:10.1097/SLA.0000000000003424