Discussion
PONV, nausea and vomiting, neuromuscular block, pain
ADVERSE REACTIONS, EVENTS, COMPLICATIONS
We evaluated and compared the effects of IONM technology on early postoperative recovery quality by means of the QoR-40 Questionnaire in patients after thyroid surgery on POD1 and POD3. Our results demonstrate that the global score of QoR-40 Questionnaire decreased significantly in the NEURO Group, mainly in the emotional state, physical comfort, physical independence and pain perception. In addition, the incidence of the PONV, the amount of remifentanil consumption and the total cost of hospitalization was significantly increased in the NEURO Group. The difference in these aspects between group NEURO and group CON meet statistical significance difference.At present, there are few studies on evaluating the early recovery quality of thyroid surgery patients by QoR-40 Questionnaire. The results of Myoung’s research [Our research found that the patients in the NEURO Group not only had a significant decrease in the global score of the QoR-40 Questionnaire on POD1 and POD3, but also had significantly lower scores in emotional state, physical comfort, physical independence and pain. When IONM applied on patients, the programs of anesthesia and surgery are different from traditional way. First, the patients in the NEURO Group only used 1*ED95 muscle relaxant during induction and no more muscle relaxant was allowed during whole procedure. This dose of muscle relaxant is less than half of that used in patients undergoing traditional thyroid surgery. As results, the clinical duration of muscle relaxant is shorter and recovery of neuromuscular block were faster in patients of NEURO group than those of CON group. Till now, there is no evidence about the postoperative recovery and the depth of neuromuscular block during operation in patients undergoing thyroid surgery. However, in laparoscopic surgery, Koo at all [Our results also show that more events of PONV in the NEURO Group, compared with the CON Group. The patients in the NEURO Group induced only 1*ED95 muscle relaxant during induction and no muscle relaxant were added during the operation. In order to avoid unexpected movement, more opioids or sedatives would be used in these patients. In our research, the dosage of remifentanil in the NEURO Group patients increased significantly, and the thyroid surgery time was shorter, the accumulation of these opioids in patients will eventually leads to adverse reactions such as nausea and vomiting after surgery. Nonetheless, whether these factors will increase the incidence of PONV needs further research. In our research, the total hospitalization cost of the patients in the NEURO Group was higher than those of the CON Group, and we believe that it was the additional costs incurred by the NIM endotracheal tube and never probe that greatly increased the total hospitalization costs of these patients.IONM technology can effectively prevent the RLNP, which make this technology gradually accepted by surgeon. However, our study confirmed that IONM technology does lead to a decrease in the early recovery quality. Although many new technologies will provide us with many conveniences at the beginning of their advent, at the same time they will also bring many new problems. This research proposed some adverse consequences of IONM technology from the perspective of anesthesia, and suggested that we need to explore a set of anesthesia programs to improve the early recovery quality of thyroid surgery patients.Although our research demonstrates that IONM technology reduced early recovery quality of thyroid surgery, it did not negate this technology, but to improve this technology. It is necessary to optimize anesthesia protocol to improve early recovery quality, and it also put forward directions for future research. In order to cooperate with surgeons to improve this technology, it is particularly important to explore a set of anesthesia programs to improve the early recovery quality. Our future research will focus on explore how to improve the early recovery quality of thyroid surgery patients with IONM technology without affecting the operation of surgeon.There are some limitations in this research. First, we didn’t measure the train-of-four ratio and balloon pressure in this study, so we haven’t direct evidences to say that the lower QoR40 score is associated with the smaller dose of muscle relaxant and larger size of inflation balloon used in patients undergoing thyroid surgery with IONM. This study was not designed to identify the factors involved in quality of recovery and IONM used in surgery. Our objective is to observe the effects of IONM technology on recovery quality in patients after thyroid surgery. So, we believe our results are reliable for our conclusion. We need further clinical trials to study why patients undergoing thyroid surgery with IONM suffer the worse postoperative recovery. Second, this research was not a blinded study. This is because the surgical method must be informed to the patients in detail before surgery, which cannot be concealed, and the NEURO Group also needs NIM endotracheal tube and never probe, so the anesthesiologist must also know it. Furthermore, our research did not distinguish between male and female genders. The recovery quality of male and female patients after thyroid surgery may be different. Although this does not affect the results of this study, future research should further compare the early recovery quality between different genders after the use of IONM technology. Lastly, our research concluded that the patients in the NEURO Group were less cost-effective. This is because the primary outcome of the study was the QoR-40 score, after sample evaluation according to this indicator, only 40 patients were included in each group, and all 80 patients did not suffer from RLNP eventually. With the increase of the risk of RLNP, the potential cost benefits of IONM technology will also increase. If the recurrent laryngeal nerve is injured due to the absence of IONM technology, the cost of NIM endotracheal tube and nerve probe is insignificant compared with the follow-up cost of treating RLNP and other complications.