PONV occurs mainly at 24 h after surgery, but a few patients can last for several days. There are many factors affecting PONV, including surgical factors, anesthesia methods, patient factors and other factors. Postoperative nausea and vomiting in patients with Department of Neurosurgery will increase the intracranial pressure, affect the cerebral perfusion pressure, serious damage to the nervous system, but also increase the risk of aspiration, intracranial recurrent bleeding, is not conducive to postoperative rehabilitation . Although there is a variety of alone or combined medication, but the incidence has not changed significantly in the incidence of PONV.
Nilsson I and others reported that the incidence of PONV in Department of neurosurgery was close to 80% and there was no significant difference in the incidence of PONV between tentorial and supratentorial tumors [11,14-16]. In our study, all the craniotomy and tumor resection were included in the study, and no supratentorial tumor and supratentorial tumor were compared. As a widespread complementary therapy, acupuncture appears to be effective in the treatment of many symptoms and/or disorders, partly by regulating the functions of the autonomic nervous system and neuroendocrine system, especially in improving postoperative pain relief and reducing postoperative side effects [17,18]. TEAS are an acupuncture-like technique that may produce effects similar to those elicited by acupuncture or EA treatment . In our study, it was found that there was no significant difference in the incidence of PONV between two groups after 0-2 H. However, the incidence of PONV in group TAES was significantly lower than that in the control group at the three time points of 2-6 h, 6-24 h and 24 h, and the incidence of nausea and vomiting in group was significantly lower than that in the control group, and the number of rescue antiemetics required was lower in the TAES group than in the control group.
A large number of clinical studies have shown that Transcutaneous Electrical Acupoint Stimulation (TAES) at Neiguan or Zusanli can effectively prevent the occurrence of PONV [9-15]. As a high-risk group of PONV, the incidence of PONV can be reduced after TAES treatment in craniotomy patients. However, the effect of combined stimulation of Neiguan point and Zusanli point on the incidence of PONV has not been reported. In our study, we combined multi acupoint therapy .The results showed the incidence of PONV in group TAES was significantly lower than that in the control group at the three time points of 2-6 h, 6-24 h and 24 h, and the incidence of nausea and vomiting in grand was significantly lower than that in the control group. From our point of view, a long duration of acupoint stimulation will increase patients’ discomfort and pain, especially for those in the acupuncture group. However, if the stimulation time is too short, the therapeutic effect of acupuncture on PONV will be uncertain.
Craniotomy patients as a high-risk group of PONV may be related to direct surgical stimulation injury. Study found that increased intracranial pressure directly or indirectly affects the limbic system of the thalamus and medulla oblongata, and stimulates the vagus nerve system, so that the parasympathetic excitation, thus contributing to the secretion of MTL . At the same time, elevated intracranial pressure can also directly stimulate the hypothalamus, brain stem, cerebellum, pituitary pheochromocytoma, make it secrete abnormal, leading to a large number of MTL secretion, and the center through the integration of signals, further promote the secretion of MTL in the peripheral gastrointestinal tract. Excessive MTL acts on receptors in the central and gastrointestinal tract, resulting in gastrointestinal spasm and increased stress. In our study, immediately after the plasma MTL concentration was significantly increased compared with before operation after operation in the two groups, TAES group at 12 h after the operation is restored to the preoperative level, but the control group at postoperative MTL compared with preoperative plasma concentration of 12 h and TAES group in the same period was significantly higher after 24 h plasma MTL of two groups were recovered to the preoperative level. The incidence of PONV and the degree of nausea and vomiting were decreased in group TAES, which might be related to the dynamic changes of plasma MTL concentration. The sample size in this study was relatively small, and the single-center design is another limitation. Selection bias may have resulted in discrepancies in the measurement indicators. Thus, further studies with several centers and a larger sample size are needed to thoroughly evaluate the efficacy of TEAS in perioperative pain relief, patient recovery, lung protection and prognosis improvement.
In conclusion, TEAS is a noninvasive and non-pharmacological modality for perioperative analgesi and acupuncture point stimulation is easy to learn, economical and practical, has been proved to effectively reduce the occurrence of PONV, reduce postoperative medication, thereby reducing the adverse reactions of drugs. Combination with Neiguan and Zusanli acupoint stimulation in craniotomy surgery, based on the use of conventional doses of azasetron, PONV can further reduce the incidence and severity of nausea.