Acupuncture for post anaesthetic recovery and postoperative pain: study protocol for a randomised controlled trial
© Fleckenstein et al.; licensee BioMed Central Ltd. 2014
Received: 19 February 2014
Accepted: 1 July 2014
Published: 21 July 2014
We report on the design and implementation of a study protocol entitled Acupuncture randomised trial for post anaesthetic recovery and postoperative pain - a pilot study (ACUARP) designed to investigate the effectiveness of acupuncture therapy performed in the perioperative period on post anaesthetic recovery and postoperative pain.
The study is designed as a randomised controlled pilot trial with three arms and partial double blinding. We will compare (a) press needle acupuncture, (b) no treatment and (c) press plaster acupressure in a standardised anaesthetic setting. Seventy-five patients scheduled for laparoscopic surgery to the uterus or ovaries will be allocated randomly to one of the three trial arms. The total observation period will begin one day before surgery and end on the second postoperative day. Twelve press needles and press plasters are to be administered preoperatively at seven acupuncture points. The primary outcome measure will be time from extubation to ‘ready for discharge’ from the post anaesthesia care unit (in minutes). The ‘ready for discharge’ end point will be assessed using three different scores: the Aldrete score, the Post Anaesthetic Discharge Scoring System and an In-House score. Secondary outcome measures will comprise pre-, intra- and postoperative variables (which are anxiety, pain, nausea and vomiting, concomitant medication).
The results of this study will provide information on whether acupuncture may improve patient post anaesthetic recovery. Comparing acupuncture with acupressure will provide insight into potential therapeutic differences between invasive and non-invasive acupuncture techniques.
NCT01816386 (First received: 28 October 2012)
Perioperative care has improved over the last decades. To continue this trend it is important note that the quality and speed of post anaesthetic recovery is influenced by multiple factors such as the occurrence of pain, postoperative nausea and vomiting (PONV), paralytic ileus, fatigue and sleep disturbances . Hence, a multimodal approach to prevent and minimise these factors is considered to be essential in order to enhance recovery . These include a series of elements such as providing the patient with thorough preoperative information and education concerning perioperative care, the use of safe and short-acting anaesthetics and optimal dynamic pain relief with minimal use of opioids, management of PONV, enteral nutrition, early mobilization and use of minimal invasive surgery. As a result of optimised anaesthetic protocols, patients might be fully awake earlier and breathe comfortably in the operating theatre . As a result of a more rapid recovery, fewer patients arrive in the post anaesthesia care unit (PACU) sedated, and the period during which they are at risk for airway obstruction and hemodynamic instability is reduced .
For achieving an optimised management of postoperative pain and PONV, acupuncture may be a hitherto underestimated option. Interest in the use of acupuncture in anaesthesia leads back to 1971, when James Reston, a The New York Times columnist, introduced the western world to the ancient Chinese therapy of acupuncture . Reston underwent an emergency appendectomy in China, and described acupuncture’s success in relieving his postoperative pain. From this point on, several scientists started investigating possible effects of acupuncture. Soon, Bruce Pomeranz revealed that an analgesic effect of acupuncture is mediated by the release of endorphins and can therefore be abolished by the administration of naloxone in humans . Mice deficient in opiate receptors did not experience acupuncture-mediated analgesia , which confirms the opioid-related mechanism of acupuncture-analgesia. Soon, first articles reported on the benefits of acupuncture anaesthesia in various operative procedures in China [8, 9]. As a consequence, first attempts were made to implement acupuncture in the anaesthetic framework , for example, as an option for sedation of the patient during tonsillectomy . A new modified method of anaesthesia in open heart surgery combining acupuncture analgesia and controlled respiration was established at the Department of Anaesthesiology in Gießen, Germany . Since then, general anaesthesia has markedly improved and acupuncture anaesthesia cannot be considered a first-line procedure.
However, there is evidence that acupuncture is effective in facilitating multimodal approaches in perioperative care. An approved acupuncture effect is the reduction of PONV and antiemetic consumption by stimulation of the acupuncture point PC 6 . Recent reviews support the effectiveness of acupuncture regimen in reducing postoperative pain, cumulative opioid consumption or opioid related side effects [14, 15]. However, trials are of varying quality and show heterogeneity with regard to the applied acupuncture treatments (acupuncture points used, time point of application). Accordingly, a meta-analysis on the effects of acupuncture on the intraoperative analgesic consumption and quality of anaesthesia revealed inconclusive results .
We aim to investigate the effects of a three-day permanent needle acupuncture treatment, starting in the preoperative phase at seven different acupuncture points only - five of them bilaterally - on a comprehensive set of above mentioned variables important to anaesthetic recovery (which are, preoperative anxiety, improving anaesthetic protocols, awakening, nausea and vomiting, and postoperative pain).
Patients and methods
For inclusion, patients must meet the following criteria:
Females scheduled for laparoscopic surgery of uterus, adnexa or ovaries
American Society of Anaesthesiologists (ASA)-score ≤ 2
Ability to follow study instructions and likely to attend and complete all required visits
Written informed consent
Subjects presenting with any of the following exclusion criteria may not be included in the trial:
General exclusion criteria:
Subject without legal capacity
Subject who is unable to understand the nature, scope, significance and consequences of this clinical trial
Simultaneously participation in another clinical trial or participation in any clinical trial involving administration of acupuncture within 30 days prior to inclusion
Subjects with a physical or psychiatric condition which at the investigator’s discretion may put the subject at risk, may confound the trial results, or may interfere with the subject’s participation in this clinical trial
Known or persistent abuse of medication, drugs or alcohol
Current or planned pregnancy or nursing women
Females of childbearing potential, who are not using and not willing to use medically reliable methods of contraception for the entire study duration (such as oral, injectable, or implantable contraceptives, or intrauterine contraceptive devices) unless they are surgically sterilised/hysterectomised or there are any other criteria considered sufficiently reliable by the investigator in individual cases.
Indication specific exclusion criteria:
Surgery within the last three months
Chronic pain > three months
Continuous analgesic medication with opioids longer than three days
Massive degenerative diseases
Pre-treatment with acupuncture or trigger point injection within the last two months
Randomised treatment allocation, blinding and sample-size estimation
Informed consent will be obtained from each participant. Subjects eligible for participation will be randomly assigned to one of the following study groups by using the Internet based randomisation software RANDOULETTE® (Institute of Medical Information Sciences, Biometry and Epidemiology, University of Munich):
press needle acupuncture: 25 subjects
no treatment control: 25 subjects
press plaster acupressure: 25 subjects
Stratification for age will be performed, and an equal distribution between treatment arms (ratio of 1:1:1) will be warranted.
In this trial we will use acupressure (group C) as an intervention to compare acupuncture (group A). Patients and examiners will be blinded for the patients’ assignment to treatment arms A and C. Therefore, we use press needles (0.2 mm × 1.5 mm; Seirin New Pyonex®, Seirin Corp., Shizuoka City, Japan) in group A and non-invasive Seirin press plasters in group C - a device that has successfully been validated for blinding in acupuncture trials . Press plasters do not contain a needle but a blunt knob and are in all other aspects identical to the press needles. According to group allocation, press needles or press plasters will be administered by an independent acupuncturist at the same defined acupuncture points. Instructions regarding point stimulation for subjects and study staff will also be identical. Thereby, patients and examiners will be blinded as laid down in the trial of Myazaki and colleagues who showed that neither patients nor therapists nor examiners know if a sharp tip or a blunt knob is located below the plaster. In contrast to Myazaki, patients will be allowed to stimulate their press device, so that an additional acupressure effect may be elicited, thereby enhancing the overall effects.
Participating trial physicians
Participating trial physicians are employees of the Multidisciplinary Pain Centre, Department of Anaesthesiology, University of Munich, Germany. Their average qualification is at least equal to a third year resident in the field of anaesthesiology and specialised pain medicine. They contribute to all medical duties.
The acupuncturists are physicians at the Multidisciplinary Pain Centre, Department of Anaesthesiology, University of Munich, Germany, who have passed more than 360 hours of curricular teaching in TCM and acupuncture and who routinely use acupuncture in daily clinical practice.
All standardised medication will be permitted according to the perioperative anaesthetic guideline and to the standard perioperative pain guideline, Department of Anaesthesiology, University of Munich, both based on general recommendations and guidelines of the German Society for Anaesthesiology (DGAI). In particular:
Estimated effect-site concentrations
Induction of anaesthesia
4.0 to 9.0 μg/ml
0.2 to 0.4 ng/ml
Maintenance of anaesthesia
3.0 to 4.0 μg/ml
0.12 to 0.22 ng/ml
To avoid postoperative pain all patients receive metamizol 2.5 g iv-infusions and to prevent PONV they receive dexamethasone 8 mg iv and for prevention of gastric stress ulcer they receive ranitidine 50 mg iv during surgery.
Postoperatively, subjects are treated for pain with metamizol (4 × 1.25 g/day) and the opioid piritramide (PCA; 2 mg each 10 minutes; maximum dosage 30 mg/4 hours). In case of nausea and vomiting or shivering, patients are treated according to the clinical standard.
Variations of this guideline based regimen are allowed if medically indicated. All concomitant therapies or medication are documented in the subjects’ clinical record file.
Patients allocated to the control group will undergo the standard anaesthetic procedure only.
Main outcome measure:
Recovery scores in the post anaesthesia care unit
Sub-items (0 to 2 points)
4 extremities, 2 extremities, 0 extremities
Deep breath, Dyspnoea, Apnoea
BP ± 20 mm/20% to baseline, BP ± 20 to 50 mm/20 to 40% to baseline, BP ± 50 mm/40% to baseline
Awake, Arousal on calling, Not responding
Normal, Pale, Cyanotic
Activity, Mental Status
Oriented and steady gait, Oriented or steady gait, Neither
Pain, Nausea, Vomiting
Minimal, Moderate, Severe
YES, Pain and PONV are both individually assessed
Minimal, Moderate, Severe
Intake and Output
Oral fluids and voided, Oral fluids or voided, Neither
Ability to arise
By itself, no nausea, With assistance only, Not possible, Nausea
Person, Place, Time
Score considered for discharge from PACU
≥ 9 and fulfill all ‘yes-no’ questions
Secondary outcome measure: In the pre- the intra- and the postoperative period (in PACU and at the ward) additional outcomes will be assessed (Figure 1).
○ Preoperative anxiety (State-Trait Anxiety Inventory: STAI )
▪ at baseline
▪ in the morning of the surgical day
▪ immediately before induction of anaesthesia
○ Vital signs (heart rate and blood pressure) at baseline
○ Pain intensity at rest at baseline
○ Laboratory parameters according to the surgical preoperative standard at baseline
○ Intraoperative drug consumption (analgesics, sedatives)
○ TCI effect-site concentrations
○ Vital signs (heart rate and blood pressure)
○ Bispectral Index (BIS) monitoring (recording starts prior to induction of anaesthesia)
○ Organisational time points (for example, incision to closure time; intubation to extubation time, and so on)
○ During emergence, the time point when stopping the TCI device, time to recovery of spontaneous breathing and time to extubation, time to eye opening, time to squeezing of the anaesthesiologists hand on command and orientation to time and place will be recorded if possible
○ About 15 minutes before the end of surgery, analgesia applied through the TCI pumps will be reduced (expected emergence 15 minutes) to facilitate recovery and time will be recorded. Time to extubation is defined as the time between end of anaesthesia and extubation.
○ Time course and comparison of recovery scores (Aldrete score, PADSS, In-House scoring system)
○ Pain intensity
○ Analgesic consumption
○ Concurrent medication
○ Occurrence of surgical- or anaesthesia-related events
○ Vital signs
Postoperative period (on the ward)
Patients will be visited after discharge from the PACU based on a fix scheme, which is six hours after, and three times daily on the two following postoperative days unless the patient has been previously discharged from the hospital. The following parameters will be assessed:
○ Vital signs
○ Pain intensity
○ Quantity and frequency of stimulated acupuncture points
○ Analgesic consumption
○ Concurrent medication
○ Occurrence of surgical- or anaesthesia-related events
Sample size calculation
Sample size calculation
ANOVA: Fixed effects, omnibus, one-way
A priori: Compute required sample size
Effect size f
α err probability
Power (1-β err probability)
Number of groups
Noncentrality parameter λ
Total sample size
The aim of the statistical analysis is the comparison of the main outcome measure (period from extubation to ‘ready for discharge’ from PACU) between the three study groups (intervention groups acupuncture and acupressure and no treatment control). For this variable, an non-normal distribution is assumed. Hence, a nonparametric method, the Kruskal-Wallis test will be applied. Post hoc tests will be performed by pairwise comparisons of the three study groups by the Mann-Whitney U-test and subsequent Bonferroni adjustment for multiple comparison (P-value times three). Primary outcome is defined as the time to discharge from PACU in the press needle acupuncture group in comparison to the no treatment group.
For the secondary target variables, a method according to the distribution of data will be performed. For metric variables, the structure of a normal distribution will be tested by the Kolmogorov-Smirnov test. In case of a normal distribution, a one-way ANOVA will be calculated. Otherwise a nonparametric test for independent observations like the Kruskal-Wallis test will be carried out.
The analysis of categorical data is conducted by the chi-square goodness-of-fit test. The binary case is treated by the chi-square-test of independence.
Data analysis will be performed with the SPSS statistical software system, version 15.0 (SPSS Inc., Chicago, IL, USA) and with SAS/STAT® Software (SAS Institute Inc., Cary, NC, USA). All data entry will be carried out twice.
The AcuARP trial investigates the effectiveness of acupuncture on post anaesthetic recovery and its use as an adjunct therapy to improve patient’s recovery in the whole perioperative setting.
Inclusion and exclusion criteria were held pragmatic in order to facilitate screening and recruitment. The chosen trial population is homogeneous and the operations undertaken are common; hence a maximised and improved routine care would be of general interest.
Limitations include the restricted sample size as the trial was planned as a pilot study. In case of a positive study outcome, further confirmatory studies will be needed. In addition, a standardised clinical procurement, using strictly standardised anaesthesia and standardised acupuncture regimen may impede generalizability of the findings.
Acupressure as a control procedure
The investigators have chosen acupressure as a control procedure in this trial as it provides the possibility of blinding both patients and examiners. Successful patient blinding using the press needle/plaster device has been proven by Miyazaki et al. . Examiners will be blinded too, since they do not know if a sharp needle (acupuncture) or a blunt knob (acupressure) is located below the plaster .
This special trial design will allow us to assess different needle-specific treatment effects : on the one hand, using a needle tip, acupuncture will be performed by penetrating the skin causing specific physiologic effects. Those may be distinguished from similar physiologic effects caused by acupressure, on the other hand, which can also be a strong stimulus by touching and kneading the skin, but without penetration. Emotional, hormonal and affiliative responses to touch have already been assured . By comparing acupuncture to acupressure, this trial will provide important evidence not only about the importance of the needle stimulus of acupuncture but also about whether acupressure might also bring about a therapeutic benefit in the perioperative setting. This in particular seems to be of interest when taking into account patient populations that are at higher risk of suffering from side effects from local bleeding.
The use of press needles was also chosen for other reasons. Perioperative treatment has to be practicable, applicable, safe and scientifically approved. The practicability will be given, as press needles have only to be fixed once: for this trial after inclusion, feasible in daily routine along with the anaesthesiologic consent. The chosen acupuncture sites are not within the surgical area. Patients can easily access the needles and press them if necessary. Press plasters are water resistant and sustain up to one week. The safety of acupuncture has been described in depth, suggesting that acupuncture is free of severe side effects and being considered a safe intervention . Blunt rather than sharp knobs are even less traumatic. There is a small number of trials dealing with the safety of press needles; one long-term observation over one year in cancer patients suggests a ratio of 10% of minor side effects, mostly rashes . Furthermore, press needles are short (1.7 mm) and needling sites are located in a safe distance from inner organs. Thus, severe adverse events such as pneumothorax or injury of inner organs are avoided. The scientific proof was previously subject to other trials, suggesting that it is worth using acupuncture in the perioperative setting [14, 15].
We have chosen to apply acupuncture or acupressure as interventions in a three-armed double blinded randomised controlled trial.
First, acupuncture in its philosophic meaning is not primarily supposed to ‘cure’ illness - the underlying idea is that acupuncture may harmonise Qi, which is a Chinese concept of vitality or energy, and other tensions of the human body which can lead to feelings of pleasantness, and the alleviation of respective symptoms . Several trials have shown its use different settings, for example in pain at obstetric delivery , chronic pain conditions , nausea and vomiting , seasonal allergic rhinitis , dysmenorrhoea , and so on. Hence acupuncture is known to alleviate primary symptoms.
Second, previous trials showed that single acupuncture points exist which are sensitive to alleviate specific symptoms relevant to the perioperative period, such as pericardium 6 (PC 6) in the treatment of postoperative nausea and vomiting . Other reports suggest Governing Vessel 26 (Du 26) may be successful in shock resuscitation  or the area between Large intestine 8 and 10 (LI 8 and LI 10) in acute tonsillitis and pharyngitis . Acupressure at Stomach 36 (ST 36) was able to shorten the time to first flatus passage, oral liquid intake, and improve gastrointestinal function in patients after abdominal surgery .
Third, several trials could already demonstrate its effectiveness in reducing preoperative anxiety , the amount of anaesthetic medications  or postoperative pain . Most of these trials have been performed using ear acupuncture and only a minority using traditional acupuncture.
All these key facts regarding acupuncture taken together suggest that it may be a useful adjunct in the perioperative period. Thus, our aim was to develop an effective and easily applicable acupuncture regimen for the complementary support of post anaesthetic recovery. Emphasis should focus on applicability, which is to reduce the number of needling events: therefore we choose the use of press needles in this trial, providing availability of the treatment for the patients during the whole perioperative period. Regarding an effective acupuncture, we have chosen acupuncture points which are supposed to alleviate perioperative symptoms. The decision has been made on the basis of a consensus process taking historic transmission but also scientific knowledge into account.
The choice of a strictly standardised anaesthetic regimen allows for comparability of all intra- and postoperative measures. The decision to conduct the study within the gynaecologic theatre was on the one hand due to the above mentioned uniform study population, on the other hand driven by the fact that the anaesthetic regimen in this clinic is extended for the use of TCI. TCI systems for dosage of propofol have been available since 1997, were initially developed for adult patients, with the dosage based on the basis of simulated concentration of the drug in the plasma for review: . In the following, taking into account the rate at which the drug enters the biophase of other tissues, that is the brain, the systems were adjusted to the concentration in the so-called effector sites. Today, the systems give the possibility to programme the dosage of various intravenous drugs according to different pharmacokinetic models, which, in brief, differ on the basis of research conducted to assess the suggested rates of infusion. The two systems mainly used are the pharmacokinetic models for propofol as established by Marsh  and Schnider . The Marsh model operates with fixed rate constants, whereas compartment volumes and clearances are weight proportional. The Schnider model was developed during combined pharmacokinetic-pharmacodynamic modelling studies, adjusting according to total weight, lean body mass, and height. It is recommended for the use in effect-site targeting mode for review: .
The time course of plasma/effect-site equilibration is used to describe the rate of removal of drug from the effect-site out of the body. With effect-site targeting, the TCI system manipulates the plasma concentration to achieve the effect-site concentration as rapidly as possible. When the effect-site target concentration is increased, the TCI system briefly increases the plasma concentration to an optimal level above the target effect-site concentration before temporarily stopping the infusion to allow the plasma concentration to decrease to the level of the target effect-site concentration. If the target effect-site concentration is reduced, the system stops the infusion allowing the plasma concentrations to fall, thereby generating a concentration gradient out of the effect-site, until the estimated effect-site concentration has fallen to the new target .
In our believe, the use of TCI is an adequate variable to monitor and compare intraoperative drug consumption when the estimated effect site concentrations is defined a priori, and may therefore be helpful in reducing bias from individually administered anaesthetic drugs. To our knowledge, to date, there is no better system which would improve comparability of different study groups.
This study is a three-armed, partially double blinded, randomised controlled trial to evaluate the effectiveness of acupuncture on the post anaesthetic recovery period as assessed by the time from extubation to ‘ready for discharge’ from the PACU. It can be expected to provide valuable new information on the clinical effectiveness of acupuncture improving post anaesthetic recovery parameters, which are a) preoperative anxiety relief, b) perioperative variables of anaesthesia and narcotic guidance, c) the occurrence of postoperative pain and anaesthetic side effects such as PONV or shivering. The comparison between press needle acupuncture involving a sharp needle tip and acupressure will provide important information about a) the physiologic effect of the needle stimulus compared to pressure and its impact on relieving perioperative symptoms and b) if both treatments are useful adjuncts in the routine perioperative care.
The status of the study at the time of first manuscript submission is ongoing, and we had included 50 patients.
American Society of Anaesthesiologists
German Society for Anaesthesiology
post anaesthesia care unit
Post Anaesthetic Discharge Scoring System
patient controlled analgesia
postoperative nausea and vomiting
State-Trait Anxiety Inventory
Target Controlled Infusion
Traditional Chinese medicine.
Parts of the study constitute the topics of the medical thesis of Caroline Gurschler. The study has been funded in parts by SEIRIN®.
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