Operative Time, Age, and Serum Albumin Predict Surgical Morbidity After Laparoscopic Liver Surgery

Predicting postoperative complications after pneumonectomy using machine learning: a 10-year study

BACKGROUND

Reducing postoperative cardiovascular and neurological complications (PCNC) during thoracic surgery is the key to improving postoperative survival.

OBJECTIVE

We aimed to investigate independent predictors of PCNC, develop machine learning models, and construct a predictive nomogram for PCNC in patients undergoing thoracic surgery for lung cancer.

METHODS

This study used data from a previous retrospective study of 16,368 patients with lung cancer (training set: 11,458; validation set: 4,910) with American Standards Association physical statuses I-IV who underwent surgery. Postoperative information was collected from electronic medical records to help build models based on cause-and-effect and statistical data, potentially revealing hidden dependencies between factors and diseases in a big data environment. The optimal model was analyzed and filtered using multiple machine-learning models (Logistic regression, eXtreme Gradient Boosting, Random forest, Light Gradient Boosting Machine and Naïve Bayes). A predictive nomogram was built and receiver operating characteristics were used to assess the validity of the model. The discriminative power and clinical validity were assessed using calibration and decision-making curve analyses.

RESULTS

Multivariate logistic regression analysis revealed that age, surgery duration, intraoperative intercostal nerve block, postoperative patient-controlled analgesia, bronchial blocker use and sufentanil use were independent predictors of PCNC. Random forest was identified as the optimal model with an area under the curve of 0.898 in the training set and 0.752 in the validation set, confirming the excellent prediction accuracy of the nomogram. All the net benefits of the five machine-learning models in the training and validation sets demonstrated excellent clinical applicability, and the calibration curves showed good agreement between the predicted and observed risks.

CONCLUSION

The combination of machine-learning models and nomograms may contribute to the early prediction and reduction in the incidence of PCNC.

Indications for and limitations of laparoscopic anatomical liver resection: assessment of postoperative complications stratified by complexity of liver resection

BACKGROUND

Although complex anatomical liver resections are more often being performed laparoscopically, the short-term outcomes following laparoscopic anatomical liver resection (LALR), its optimal indications, and limitations remain unclear. This study aimed to clarify the indications for and limitations of LALR by assessing the short-term outcomes.

METHODS

This retrospective study included 233 patients who underwent LALR. The complexity of LALR was categorized into three levels: Grade I (low), grade II (moderate), and grade III (high). Short-term outcomes were compared among these groups, and the risk factors for severe morbidity were identified.

RESULTS

The patients' backgrounds were similar across the three groups. Intraoperative blood loss, Pringle maneuver time, and postoperative hospital stay were comparable between grade I (n = 59) and grade II (n = 65) LALR but were greater for grade III (n = 109). The transfusion and conversion rates were similar among the three groups. The operative time increased with the rise in difficulty grade. The rate of severe morbidity was 3.4% in grade I, 6.2% in grade II, and 16.5% in grade III LALR (P = 0.012). Multivariable analysis identified three perioperative risk factors for severe morbidity: Operative time of ≥ 540 min (odds ratio [OR] = 4.762, P = 0.009), intraoperative blood loss of ≥ 350 mL (OR = 3.982, P = 0.024), and preoperative serum albumin of ≤ 3.8 g/dL (OR = 3.518, P = 0.035).

CONCLUSIONS

Grade II LALR can be performed with the same level of safety as grade I LALR. However, grade III LALR has a higher complication rate than grades I and II LALR, and the risk increases further due to longer operative time and greater blood loss.

Robotic versus laparoscopic liver resection for difficult posterosuperior segments: a systematic review with a meta-analysis of propensity-score matched studies

BACKGROUND

The outcomes of minimally invasive liver surgery for posterosuperior segments (PS) are still debated. Since the results of ongoing trials focusing on the results of laparoscopic liver resection (LLR) and robotic liver resection (RLR) in this setting are still awaited, the best evidence currently comes from retrospective propensity-score matched (PSM) studies. The aim of this meta-analysis was to assess the outcomes of RLR for difficult located lesions and to provide evidence for its use in clinical practice.

METHODS

A systematic review with meta-analysis was conducted to evaluate the safety and efficacy of LLR and RLR for PS segments. The Medline, Embase and Web of Science Library electronic databases were searched to identify available research published up to June 2024.

RESULTS

Five studies with a total of 2907 patients (RLR: n = 1084; LLR: n = 1823) were included in the meta-analysis. The RLR group had less estimated blood loss (EBL) (MD: - 88.3, 95% CI - 144.2-- 32.3; p = 0.012), fewer blood transfusions (OR 0.70, 95% CI 0.39-0.80, p = 0.033), and a shorter operative time (MD - 27.3, 95% CI - 49.4-- 5.1; p = 0.027). No differences in postoperative morbidity, mortality and R1 resection rates were observed.

CONCLUSION

RLR for lesions in the PS segments are safe and effective, and may have superior surgical outcomes than LLR.

Risk factors for wound complications after associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) compared to repeated liver resection - a propensity score matching analysis

AIM

Sufficient liver function is crucial in extracellular matrix growth, hemostasis, and wound healing. Repeated abdominal surgery is a known risk factor for the development of wound complications. This study aimed to evaluate this high-risk constellation in patients undergoing associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) and repeated liver resections (RLR) in comparison to single liver resection (SLR).

METHOD

Forty patients who underwent ALPPS between 2011 and 2020 were evenly matched with patients undergoing RLR or SLR (n = 40 per group) using propensity scores. Postoperative outcomes were compared and factors associated with wound complications were analyzed.

RESULTS

Postoperative wound complications were significantly more frequent in ALPPS group (p = 0.001). The reoperation rate was not significantly different between the three groups (p = 0.143). However, surgical reintervention due to wound complications occurred more frequently in the ALPPS group in relation to RLR and SLR (17.5% vs. 7.5% and 5% respectively). Length of stay was significantly longer in the ALPPS group (p = 0.033). ALPPS was an independent risk factor for postoperative wound complication (OR = 8.55, 95% CI:1.07-68.44, p = 0.043). Risk factor analysis identified age ≥ 60 years (OR = 27.64, 95% CI:3.09-246.75, p = 0.003), BMI ≥ 30 kg/m2 (OR = 30.21, 95% CI:3.35-271.83, p = 0.002), and low postoperative albumin levels (OR = 168.41, 95% CI:7.76-3651.18, p = 0.001) as independent predictors of postoperative wound complications after major liver resection.

CONCLUSION

Patients undergoing ALPPS and RLR are faced with a high risk of developing wound complications. Older age, obesity, a history of previous abdominal surgery, and a decreased postoperative albumin level were independent risk factors for wound complications.

A Decade of Experience Between Open and Minimally Invasive Hepatectomies for Hepatocellular Carcinoma

Background and Objectives: Hepatic resection offers promising outcomes for patients with hepatocellular carcinoma (HCC) but can be constrained by factors like patient suitability. Continuous advancements in laparoscopic and robotic technologies have made minimally invasive hepatectomies (MIHs) a viable alternative to open hepatectomies with benefits in terms of recovery and complications. Materials and Methods: We completed a retrospective review on 138 HCC patients who underwent OH or MIH between 2010 and 2020 at the Hume-Lee Transplant Center. Univariate and multivariate analyses were completed on demographic, clinical, and tumor-specific data to assess the impact of these variables on overall and disease-free survival at 1, 3, and 5 years. Preoperative metrics like length of hospital stay (LOS) and operation duration were also evaluated. Results: Of the 109 OH and 29 MIH patients, MIH patients demonstrated shorter LOS and operative times. However, overall survival (OS) and disease-free survival (DFS) were similar between groups, with no significant variations in 1-, 3-, and 5-year survival rates. Age > 60 years and a lack of preoperative transcatheter arterial chemoembolization (TACE) were significant predictors of inferior OS and DFS in multivariate analyses. Conclusions: MIH is an efficient substitute for OH with comparable survival, even in older patients. The reduced LOS and operation time enhance its feasibility, and older patients previously denied for curative resection may qualify for MIH. Preoperative TACE also enhances survival outcomes, emphasizing its general role in managing resectable HCCs. Both robotic and laparoscopic hepatectomies offer acceptable short- and long-term clinical outcomes, highlighting MIH as the standard choice for HCC patients.

Risk factors and clinical impact of seroma formation following laparoscopic inguinal hernia repair: a retrospective study

BACKGROUND

Although laparoscopic inguinal hernia repair (LIHR) has advantages over open surgery, postoperative seroma formation remains an issue. This study aimed to investigate the risk factors and clinical outcomes of seroma formation in patients undergoing LIHR.

METHODS

From January 2016 to March 2023, clinical data of patients who underwent LIHR were retrospectively analyzed. Patients who developed seroma and those who did not were classified into the seroma and non-seroma groups, respectively. The demographic and clinical characteristics were compared between the two groups. Univariate and multivariate logistic regression analyses were performed for variables of interest. The receiver operating characteristic curve was used to evaluate the risk factors of the binary logistic model, and the cutoff value for each risk factor was obtained.

RESULTS

Data of 128 patients were evaluated. Compared with patients in the non-seroma group, those in the seroma group had a higher body mass index (BMI) (P < 0.001), more direct hernias (P < 0.001), larger hernial orifice size (P < 0.001), more laparoscopic total extraperitoneal hernioplasty (TEP) (P < 0.001), more frequent reduction of hernial sac (P = 0.011), and lower preoperative serum albumin level (PSAL) (P < 0.001). Multivariate logistic regression analyses performed on these variables showed that high BMI (P = 0.005), large hernial orifice (P = 0.001), TEP (P = 0.033), and low PSAL (P = 0.009) were risk factors for seroma formation. Compared with the non-seroma group, the seroma group exhibited a higher numerical rating scale score for postoperative pain (P < 0.001), and longer hospital stays (P = 0.032).

CONCLUSIONS

BMI (> 24.5 kg/m2), hernial orifice size (> 2.5 cm), TEP, and PSAL (< 32.5 g/L) were independent risk factors of postoperative seroma formation in patients who underwent LIHR. Although most seromas resolve spontaneously without surgical intervention, seroma formation results in increased patient pain and prolonged hospital stay.

The oncologic outcome and prognostic factors for solitary colorectal liver metastasis after liver resection

BACKGROUND

Studies on prognostic factors for patients undergoing surgery to treat solitary liver metastases originating from colorectal cancer (CRC) are limited. This study aimed to analyze significant prognostic factors associated with tumor recurrence and long-term survival after liver resection for solitary colorectal liver metastasis.

METHODS

Data from 230 patients with solitary liver metastases from CRC who received liver resection between 2010 and 2019 were retrospectively analyzed. Recurrence-free survival (RFS) and overall survival (OS) were accessed with the Kaplan-Meier method and log-rank test. Cox regression multivariate analysis identified independent variables associated with RFS and OS. Nomograms were developed to predict patient outcomes after surgery.

RESULTS

The 3- and 5-year OS rates were 72.3% and 59.8%, respectively. The 3- and 5-year RFS rates were 40.0% and 27.1%, respectively. Multivariate analysis revealed age ≥ 70 years, resection margin width < 10 mm, initial N2 stage, hypoalbuminemia before surgery, and neutrophil-to-lymphocyte ratio (NLR) ≥ 3 after surgery as independent prognostic factors for OS. For RFS, initial N2 stage, hypoalbuminemia before surgery, NLR ≥ 3 after surgery, elevated carcinoembryonic antigen (CEA) levels after surgery, and CEA ratio (after/before liver resection) < 0.3 were identified as independent prognostic factors.

CONCLUSION

This study demonstrated that initial N2 stage, hypoalbuminemia before liver resection, and NLR ≥ 3 after liver resection exert a significant association on the RFS and OS of patients undergoing surgery for solitary liver metastases from CRC. Thus, upfront chemotherapy, prompt postoperative chemotherapy, and intensive postoperative surveillance are mandatory for patients having these adverse factors.

Laparoscopic hepatectomy for hepatocellular carcinoma in patients with clinically significant portal hypertension: a systematic review and meta-analysis

OBJECTIVE

To compare the effects of laparoscopic hepatectomy (LH) on the short-term and long-term outcomes in hepatocellular carcinoma (HCC) patients with and without clinically significant portal hypertension (CSPH).

METHODS

A systematic literature search of the PubMed, EMBASE, and Cochrane databases was performed for articles published from inception to March 1, 2023. Meta-analysis of surgical and oncological outcomes was performed using a random effects model. Data were summarized as mean difference and risk ratio with 95% confidence intervals.

RESULTS

Five cohort studies with a total of 310 HCC patients were included (CSPH 143; Non-CSPH 167). In terms of surgical outcomes, estimated blood loss and the length of hospital stay were significantly lower in the Non-CSPH group than in the CSPH group. There were no significant differences between the two groups regarding other surgical outcomes, including the operative time, ratio of conversion to open surgery, and overall complication rate. In addition, there were also no significant differences between the two groups regarding the oncological outcomes, such as 1-, 3-, and 5-year overall survival.

CONCLUSIONS

HCC patients with and without CSPH who underwent LH had comparable surgical and oncological outcomes. LH is a safe and effective treatment for HCC patients with CSPH under the premise of rational screening of patients.

Robotic versus laparoscopic liver resection for liver malignancy: a systematic review and meta-analysis of propensity score-matched studies

OBJECTIVE

How different surgical procedures, including the robotic-assisted liver resection (RLR) and laparoscopic liver resection (LLR), can affect the prognosis of patients with liver malignancies is unclear. Thus, in this study, we compared the effects of RLR and LLR on the surgical and oncological outcomes in patients with liver malignancies through propensity score-matched cohort studies.

METHODS

The PubMed, Embase, and Cochrane databases were searched using Medical Subject Headings terms and keywords from inception until May 31, 2023. The quality of the included studies was assessed using the Newcastle-Ottawa quality assessment scale. The mean difference with 95% confidence interval (95% CI) was used for analysis of continuous variables; the risk ratio with 95% CI was used for dichotomous variables; and the hazard ratio with 95% CI was used for survival-related variables. Meta-analysis was performed using a random-effects model.

RESULTS

Five high-quality cohort studies with 986 patients were included (370 and 616 cases for RLR and LLR, respectively). In terms of surgical outcomes, there were no significant differences in the operation time, conversion rate to open surgery, overall complication rate, major complication rate, and length of hospital stay between the RLR and LLR groups. In terms of oncological outcomes, there were no significant differences in the 5-year overall survival and disease-free survival between the two groups.

CONCLUSION

Surgical and oncological outcomes are comparable between RLR and LLR on patients with liver malignancies. Therefore, the benefits of applying RLR in patients with liver malignancies need to be further explored.

A Single Centre Experience with Pre-Operative Markers in the Prediction of Outcomes after Liver Resection for Hepatocellular Carcinoma

BACKGROUND AND AIM

The C-reactive protein to albumin ratio, albumin-bilirubin index and platelet-albumin-bilirubin index have emerged as prognostic scores in hepatocellular carcinoma, although their clinical utility remains unclear, with ongoing investigation in multiple patient populations. This study aims to report survival outcomes and evaluate these indices in a cohort of patients undergoing liver resection for hepatocellular carcinoma in a tertiary Australian centre.

METHODS

This retrospective study reviewed data from the Department of Surgery at Austin Health and electronic health records (Cerner corporation). The impact of pre, intra and post-operative parameters on post-operative complications, overall and recurrence free survival were analyzed.

RESULTS

163 liver resections were performed in 157 patients between 2007 and 2020. Post-operative complications occurred in 58 patients (35.6%), with pre-operative albumin < 36.5 g/L (3.41(1.41-8.29),p = 0.007) and open liver resection (3.93(1.38-11.21),p = 0.011) demonstrating independent predictive significance. 1,3 and 5-year overall survival was 91.0%, 76.7% and 66.9% respectively, with a median survival time of 92.7 months (81.3-103.9). Hepatocellular carcinoma recurred in 95 patients (58.3%) with a median time to recurrence of 27.8 months (15.6-39.9). 1,3 and 5 year recurrence-free survival rates were 94.0%, 73.7% and 55.1% respectively. Pre-operative C-reactive protein-albumin ratio > 0.034 was significantly associated with reduced overall (4.39(1.19-16.16),p = 0.026) and recurrence-free (2.53(1.21-5.30),p = 0.014) survival.

CONCLUSION

C-reactive protein-albumin ratio > 0.034 is a strong predictor of poor prognosis following liver resection for hepatocellular carcinoma. In addition, pre-operative hypoalbuminemia was associated with post-operative complications, and future studies are required to assess the potential benefits of albumin replacement in reducing post-surgical morbidity.

Robotic-assisted Gynecological Surgery in Older Patients - a Comparative Cohort Study of Perioperative Outcomes

Study design Because of current demographic developments, a hypothesis was proposed whereby older female patients aged > 65 years can be safely operated using minimally invasive, robotic-assisted surgery, despite having more preoperative comorbidities. A comparative cohort study was designed to compare the age group ≥ 65 years (older age group, OAG) with the age group < 65 years (younger age group, YAG) after robotic-assisted gynecological surgery (RAS) in two German centers. Patients and methods Consecutive RAS procedures performed between 2016 and 2021 at the Women's University Hospital of Jena and the Robotic Center Eisenach to treat benign or oncological indications were included in the study. The age groups were compared according to their preoperative comorbidities (ASA, Charlson comorbidity index [CCI], cumulative illness rating scale - geriatric version [CIRS-G]) and perioperative parameters such as Clavien-Dindo (CD) classification of surgical complications. Analysis was performed using Welch's t -test, chi ² test, and Fisher's exact test. Results A total of 242 datasets were identified, of which 63 (73 ± 5 years) were OAG and 179 were YAG (48 ± 10 years). Patient characteristics and the percentage of benign or oncological indications did not differ between the two age groups. Comorbidity scores and the percentage of obese patients were higher in the OAG group: CCI (2.7 ± 2.0 vs. 1.5 ± 1.3; p < 0.001), CIRS-G (9.7 ± 3.9 vs. 5.4 ± 2.9; p < 0.001), ASA class II/III (91.8% vs. 74.1%; p = 0.004), obesity (54.1% vs. 38.2%; p = 0.030). There was no difference between age groups, even grouped for benign or oncological indications, with regard to perioperative parameters such as duration of surgery (p = 0.088; p = 0.368), length of hospital stay (p = 0.786; p = 0.814), decrease in Hb levels (p = 0.811; p = 0.058), conversion rate (p = 1.000; p = 1.000) and CD complications (p = 0.433; p = 0.745). Conclusion Although preoperative comorbidity was higher in the group of older female patients, no differences were found between age groups with regard to perioperative outcomes following robotic-assisted gynecological surgery. Patient age is not a contraindication for robotic gynecological surgery.

Case report: dual primary malignancies treated by laparoscopic multiorgan resection with natural orifice specimen extraction surgery

With microtrauma becoming a consensus, in order to improve surgical treatment capability, the clinical application of laparoscopic multiorgan resection is becoming more and more complicated and diversified. Recently, we successfully presented a case of transvaginal specimen extraction surgery that included laparoscopic anatomical left hemihepatectomy combined with laparoscopic total hysterectomy and bilateral adnexectomy and the pelvic and para-aortic lymphadenectomy. The patient, a 75-year-old woman, was hospitalized with abnormal vaginal discharge and bleeding. The pathologic diagnosis of uterine curettage was endometrioid adenocarcinoma. After completing examinations such as color Doppler ultrasound, CEUS, MRCP and thoracoabdominal enhanced spiral CT, preoperative diagnosis was considered as endometrial cancer and a space-occupying lesion in the liver (primary or secondary site)?. No lymphatic or distant metastasis had been found. We also excluded Lynch syndrome by digestive endoscopy and gene sequencing. After a multidisciplinary consultation, the patient underwent surgery under general anesthesia on 24 September 2021. The operation was completed uneventfully in 6 hours, then the patient was transferred to the ICU for follow-up monitoring. The patient began to eat and was able to leave bed on the 4th postoperative day. According to immunohistochemistry, the patient's postoperative diagnosis was intrahepatic cholangiocarcinoma (ICC) and endometrial cancer. Compared with open surgery, laparoscopic multiorgan resection with natural orifice specimen extraction surgery (NOSES) has many advantages such as fewer traumas, shorter recovery time, and better postoperative quality of life. However, combined large-scale laparoscopic surgeries of different organs can be challenging for surgeons and anesthesiologists. No similar cases have been searched.