Therapeutic Suggestions During General Anesthesia Reduce Postoperative Nausea and Vomiting in High-Risk Patients – A Post hoc Analysis of a Randomized Controlled Trial

Abstract

Postoperative nausea and vomiting (PONV) are one of the most adverse events after general anesthesia, a distressing experience, and pose a risk to the patient. Despite advances in drug prophylaxis and PONV treatment, the incidence remains high and additional non-pharmacological treatments are needed. In this post hoc analysis of a recently published double-blind multicenter randomized controlled trial on the efficacy of intraoperative therapeutic suggestions on postoperative opioid dosage, we analyzed the effects of intraoperative therapeutic suggestions on PONV. We focus on patients with a high risk of PONV (Apfel risk score of 3–4) and distinguished early (first two postoperative hours) and delayed PONV (2–24 h). A total of 385 patients with a moderate or high risk for PONV were included. The incidence of early and delayed PONV was reduced (22.7–18.3 and 29.9–24.1%, respectively), without statistical significance, whereas in high-risk patients (n = 180) their incidence was nearly halved, 17.2 vs. 31.2% (p = 0.030) and 20.7 vs. 34.4% (p = 0.040), corresponding to a number needed to treat of 7 to avoid PONV. In addition, there was a significant reduction in PONV severity. In a multivariate logistic regression model, assignment to the control group (OR 2.2; 95% CI: 1.1–4.8) was identified as an independent predictor of the occurrence of early PONV. Our results indicate that intraoperative therapeutic suggestions can significantly reduce the incidence of PONV in high-risk patients. This encourages the expansion of therapeutic suggestions under general anesthesia, which are inexpensive and virtually free of side effects.Clinical Trial Registration: German Clinical Trials Register, https://drks.de, registration number: DRKS00013800.

Hypnosis in psychotherapy, psychosomatics and medicine. A brief overview

“…This is plausible insofar as in such situations a person's self-efficacy is reduced to the point of absolute helplessness and they are dependent on effective actions and instructions ("suggestions") from others. If voluntary competence to act is reduced and attention is highly focused, this corresponds to one of the prerequisites of hypnosis, namely motor restriction and sensory deprivation (Peter, 1994, and such situations possibly produces a state of situational hypersuggestibility (Hull, 1933): Patients at the doctor's and especially in hospital are highly receptive to all information, positive and negative, placebo and nocebo suggestions (Hansen and Zech, 2019;Zech et al, 2019Zech et al, , 2020Zech et al, , 2022, this even applies to operations under general anaesthesia (Nowak al., 2020(Nowak al., , 2022. Whether this situational hypersuggestibility correlates with high hypnotizability and/or even requires a special hypnotic "trance" state requires further investigation, just as the relationship between hypnotizability and suggestibility in general is still open to further research.…”

Touching the unconscious in the unconscious – hypnotic communication with unconscious patients

“…However, recently the effect of hypnotic suggestions was investigated again. A controlled, randomized, triple-blinded multicenter study was conducted at five German university hospitals with 385 patients undergoing painful surgery of 1-3 h duration under general anesthesia (Nowak et al, 2020(Nowak et al, , 2022. A 20-min text set to background music, followed by a 10-min break, was played repeatedly over earphones for the entire duration of the surgery, and a text on anesthesia withdrawal was played in the final phase.…”

“…Incidence of both early and late manifestations, i.e., early and delayed PONV, were halved. Moreover, an observed NNT of 7 indicates that medication with antiemetics can be avoided entirely in 1 of 7 patients ( Nowak et al, 2022 ). This study demonstrates high efficacy in reducing side effects of anesthesia and surgery with a simple, practical, non-pharmacological intervention.…”

The Effect of Preoperative State-Trait Anxiety Level and Anesthesia Technique on Postoperative Nausea and Vomiting

“…Nausea is defined as a feeling of discomfort in the stomach, and vomiting is defined as the expulsion of stomach contents. Postoperative nausea and vomiting carry a risk of serious complications such as wound dehiscence, aspiration, pneumonia, fluid electrolyte imbalance, and increased intracranial pressure (9)(10)(11)(12).…”