The duration of hospitalization is a pivotal metric that clinicians and patients employ to assess the surgical prognosis, while simultaneously constituting a vital component of curtailing hospitalization expenses. In the context of knee arthroscopic surgery, elements that may impact the duration of hospital stay encompass patients’ characteristics, the nature of the surgical procedure and perioperative anesthesia care. In evaluating patient-related risk factors, diabetes mellitus, BMI are known to have higher risk for morbidity and readmission following all arthroscopy13. While our results confirmed that diabetes mellitus or BMI was not an independent influencing factor. Surgical factors, including ligamentous repair, operations involving 3 or more Current Procedural Terminology (CPT) codes are proved to be risk factors for complications after arthroscopic knee surgery2. Nevertheless, little is known about the anesthesia-related factors that could facilitate better prognosis for patients.
As an anesthetic and analgesic drug, ketamine is widely used for perioperative pain management14–17. Its potent analgesic effect can even last up to 48 hours after surgery, significantly reducing the need for postoperative opioid use18. Over the past two decades, clinical research has increasingly recognized the clinical benefits that ketamine can bring to patients19. In addition to its aforementioned postoperative analgesic effects, it can also reduce the incidence of postoperative nausea and vomiting and improve postoperative depression20–22.Esketamine, as compared to conventional ketamine, exhibits a more potent analgesic effect and a faster in vivo clearance rate, despite being administered at only half the dosage19. However, few studies have explored whether esketamine can ultimately provide benefits in terms of post-operative hospitalization days. The principal finding of this study was the identification of esketamine use as independent factor influencing PD3.Additionally, ketamine has gained increasing attention for its effective intraoperative anti-inflammatory properties23. A previous meta-analysis showed that ketamine significantly reduces the expression of the pro-inflammatory cytokine IL-6 after surgery and increases the expression of the anti-inflammatory cytokine IL-1024. Therefore in future investigations, it would be of value to delve into the potential of esketamine in modulating the inflammatory response profile of knee joint cells that are intricately associated with inflammation, including chondrocytes and synovial cells. However, our investigation did not reveal any significant improvement in postoperative wound infection with the administration of esketamine(Table 5), which may be attributed to inadequate sample size in our study.
A longer surgery duration has previously been identified as a risk factor for extended length of stay, increased transfusion risk, wound dehiscence, death, surgical-site infection, sepsis and hospital readmission in patients underwent knee arthroscopic surgery2. Consistent with the previous study, our work demonstrated that an increase in operative time was associated with a decreased ratio of PD3(OR = 0.99, 95% CI(0.97-1.00).Despite the weak correlation between surgery duration and postoperative outcomes observed in our study, the finding highlights the importance of considering surgery duration as a modifiable risk factor in perioperative management, which would have significant implications for optimizing perioperative strategies and improving patient outcomes in clinical practice.
However, imitations of this study include the retrospective nature in which analysis was performed in a single center. There likely exists large variability in patient characteristics prior to knee arthroscopic surgery. Established risk factors influencing hospital stay such as surgery type, operative duration were collected in our study and controlled for multivariate analysis, however postoperative pain score was not recorded, which may lead to unpredictable bias. Furthermore, several clinical studies have tried including the surgical skill level of surgeons in regression models in order to better explain the impact on outcomes. Although this study lacks correction factors for the surgical skill level, the arthroscopic knee surgery was only performed by one fixed surgical team, thus avoiding any confounding effect on outcome analyses. Additionally, recording using dosage and using time of intraoperative analgesics would provide valuable guidance for anesthesiologist in clinical practice. Future studies focused on knee arthroscopic surgery should be more rigorous methodologically.