Lung cancer yet ranks first among all cancers in terms of incidence and death rates worldwide, including in China. Surgery is deemed as the optimal strategy or option for patients with early or resectable tumors. Due to poor lung function and sequential PPCs, patients with lung cancer often require long hospitalization and more postoperative costs (15, 16). Recently, growing attention has been paid to an emerging ERAS program (17–20), which is effective in decreasing postoperative morbidity and mortality and was formerly known as the “fast-track surgery” introduced by Kehlet and Mogensen in 1999 (21). Many institutions have proposed ERAS protocols according to the medical care conditions. ERAS firstly put forward for colorectal surgery, and has validated clinical benefits in other surgeries in decreasing morbidity, hospital stay, and costs (17–20).
Some issues should be noticed before the use of ERAS into lung cancer surgery. 1) Advances in radiography and prevalent cancer screening programs have considerably increased the chance for early detection, for higher detection rate of early-stage or resectable lesions and for timely surgical therapy. 2) VATS, which significantly alters thoracic operational steps and brings considerable benefits, such as less wound pain and shorter hospital stay, becomes the mainstream approach for lung cancer surgery, especially at early-stage (22–24). 3) The components of ERAS programs vary among different institutions, and the practice of ERAS elements is probably relying on clinical experience. Many elements of ERAS programs become routine. It is hard to judge whether temporal changes in practice can improve the outcomes, rather than the use of the ERAS pathway, per se.
Our ERAS team with multidisciplinary collaboration was established in 2015 to more professionally and effectively carry out the ERAS pathway. The patients can counsel and be supervised by trained nurses to complete the ERAS phases. Breathing exercise and postoperative nutrition procedures were conducted by specialized physical therapists and nutritionists.
We found the proportions of patients during the ERAS pathway with early-stage (stage 0 or I) versus the routine pathway did not significantly increase, but the proportion of VATS increased. The possible reason was that the wide promotion of minimal invasive surgery and the advantage of VATS were commonly accepted or recognized, especially by young surgeons. From the surgeons’ respective, the implement of minimal invasive surgery is also the important element of ERAS protocol, as it offers patients with shorter surgical time, less intraoperative blood loss, postoperative pain and surgical trauma, and faster sequential recovery after surgery. In guidelines for ERAS drafted by the ERAS Society and the European Society of Thoracic Surgeons (ESTS), a VATS approach for lung resection is recommended for early-stage lung cancer with high evidence level and strong recommendation grade (20). According to the results, lower surgery time, and less blood loss was observed in ERAS group, showing the potential benefits that this minimal invasive approach provided in patients’ postoperative recovery.
Postoperative pulmonary complications (PPCs) were considered as important negative influences on the recovery outcomes, increasing the risk of mortality. Evidence shows that ERAS regimens integrating effective perioperative courses prevent PPCs for patients with lung cancer undergoing lung resection (25). Controversially, Brunelli et al. reported no significant difference in postoperative morbidity after the use of an ERAS program. Potential reasons include study heterogeneity, the exact structures of ERAS program, and the quality of implementation or patient selection (26). We found lower occurrences of PPCs and pneumonia in the ERAS group compared to routine pathway. Theoretically, elements including VATS approach, pain, and VTE management may jointly improve the postoperative recovery and decrease the PPC rate. Furthermore, results of multivariable analysis present that the ERAS intervention was the independent factor of PPCs as well as pneumonia and atelectasis, validating its effectiveness improving postoperative recovery of those patients. Another essential variable is LOS. Proper pain control, early mobilization, chest tube removal and few complications contribute to a shorter LOS, indicating better postoperative recovery. A recent systematic review summarized the RCTs concerning ERAS, and reported that four of the five RCTs indicated the mean LOS was significantly shortened by the ERAS (26). Our study reveals shorter LOS and postoperative LOS in ERAS group, suggesting better recovery in those population. Meanwhile, lower in-hospital expenses including drug costs and shorter duration of indwelling chest tube were found in ERAS group, which also provided evidence of the effectiveness of the ERAS program.
In the present study, we also explored the predictive factors for developing a PPCs. Besides the ERAS intervention, age, COPD, and FEV1 can also significantly independently predict the risk of PPCs. We established a nomogram model to forecast the accurate risk score for developing a PPC. The interpretation of the nomogram is simple. As shown in Fig. 1, for example, a patient with age of 82 (4 points), a FEV1 value of 1.99 L (7 points), without ERAS intervention (1 point), and without a COPD status (0 point) will receive 12 points in total, which responses to a 50% risk of developing postoperative pulmonary complications. In other words, by calculating the points of the four variables, the clinician can easily predict the risk score of PPCs after lung surgery, and guide personalized clinical decision-making. A nomogram provides enhanced information beyond simply the identification of the risk factors for certain outcomes [27].
The study has some limitations that can hardly be ignored. Firstly, all the patients were selected from a single regional center by a small group of surgeons, and no propensity-matching was analyzed in the control group. As a retrospective study, lack of randomization limited the control of intergroup bias. Secondly, the effects of an ERAS program, the sole effects of standardization, and whether temporal changes in practice improved the outcomes, rather than the use of the ERAS pathway, per se cannot be easily determined. Thirdly, the selection of patients receiving anatomical resection resulted in relevant bias and the sequential limitation of conclusion generalization. Moreover, we did not detail the in-hospital costs, so we cannot explore the economic outcomes of the ERAS program. Last not the least, we did not assess the pain control nutrition-related variables between groups, and cannot directly assess the role of pain and nutrition management in ERAS program. As for the nomogram, limited by the sample size, we didn’t undergo the external validation process to test the reliability of the model which would restrict the utilization of the model.
In conclusion, the use of an ERAS pathway improved the postoperative outcomes, including shorter LOS and lower occurrence of PPCs, providing benefits of postoperative recovery for patients with lung cancer undergoing surgical treatment.