You are here

  • Home
  • Archive
  • Volume 12, Issue 6
  • Effect of intramuscular midazolam premedication on patient satisfaction in women undergoing general anaesthesia: a randomised control trial

Article Text

Article menu
Anaesthesia
Original research
Effect of intramuscular midazolam premedication on patient satisfaction in women undergoing general anaesthesia: a randomised control trial
  1. Seung Woo Song1,2,
  2. Younghyun Jin2,
  3. Hyunjae Lim2,
  4. Jonghoon Lee2,
  5. Kwang Ho Lee1,2
  1. 1Department of Anesthesiology and Pain Medicine, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, Korea
  2. 2Department of Anesthesiology and Pain Medicine, Wonju Severance Christian Hospital, Wonju, Korea
  1. Correspondence to Professor Kwang Ho Lee; khlee6006{at}yonsei.ac.kr

Abstract

Objective To determine the effect of premedication with intramuscular midazolam on patient satisfaction in women undergoing general anaesthesia.

Trial design, setting and participants Double-blind, parallel randomised control trial at a tertiary care medical centre in South Korea. Initially, 140 women aged 20–65 years who underwent general anaesthesia and had an American Society of Anesthesiology physical status classification of I or II were randomly assigned to the intervention group or the control group, and 134 patients (intervention n=65; control n=69) completed the study.

Intervention Intramuscular administration of midazolam (0.05 mg/kg) or placebo (normal saline 0.01 mL/kg) on arrival at the preoperative holding area.

Main outcomes The primary outcome was the patient’s overall satisfaction with the anaesthesia experience as determined by questionnaire responses on the day after surgery. Satisfaction was defined as a response of 3 or 4 on a five-point scale (0–4). The secondary outcomes included blood pressure, heart rate, oxygen desaturation, recovery duration and postoperative pain.

Results Patients who received midazolam were more satisfied than those who received placebo (percentage difference: 21.0%, OR 3.56, 95% CI 1.46 to 8.70). A subgroup analysis revealed that this difference was greater in patients with anxiety, defined as those whose Amsterdam Preoperative Anxiety and Information Scale anxiety score was ≥11, than that for the whole sample population (percentage difference: 24.0%, OR 4.33, 95% CI 1.25 to 14.96). Both groups had similar heart rates, blood pressure and oxygen desaturation.

Conclusion Intramuscular administration of midazolam in women before general anaesthesia in the preoperative holding area improved self-reported satisfaction with the anaesthesia experience, with an acceptable safety profile.

Trial registration number KCT0006002.

  • adult anaesthesia
  • anaesthetics
  • quality in health care

Data availability statement

Data are available on reasonable request.

http://creativecommons.org/licenses/by-nc/4.0/

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

https://doi.org/10.1136/bmjopen-2021-059915

Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    Strengths and limitations of this study

    • This study prospectively investigated the role of midazolam premedication in women undergoing general anaesthesia to improve patient satisfaction.

    • The intervention in this study was the administration of intramuscular midazolam, the most widely used benzodiazepine, or placebo.

    • Limitations are the fact that the sample was drawn from a single ethnic group and that the study was not powered for subgroup analysis.

    Introduction

    Preoperative anxiety is a common problem in patients undergoing surgery. Surgical patients are prone to anxiety due to fear of intraoperative awareness, postoperative pain, complications and mortality.1 2 The incidence of preoperative anxiety varies depending on the assessment tool used and target population. One study using the Amsterdam Preoperative Anxiety and Information Scale (APAIS) reported that 44% of patients were worried about anaesthesia.1 Apart from an unpleasant emotional problem, anxiety positively correlated with postoperative pain, nausea, vomiting and adverse outcomes, such as infection and mortality,2 3 and negatively correlated with patient satisfaction.4 5

    Pharmacological intervention is an option for attenuating preoperative anxiety. Benzodiazepines are one of the main drug classes used for premedication prior to surgery, alongside beta-adrenoreceptor blockers and opioids.6 Midazolam is a widely used benzodiazepine that produce anxiolytic and considerable anterograde amnesic effects. It has numerous advantages including a short half-life, minimal haemodynamic turbulence, and only mild respiratory depression.7 In addition, midazolam can be easily administered via oral, rectal, intramuscular, intravenous and intranasal routes. Preoperative midazolam is often administered intramuscularly, with various studies having examined this route of administration.8–11

    Some studies have reported the effect of premedication with benzodiazepines on patient satisfaction.5 12–14 However, the beneficial role of benzodiazepines as premedication remains controversial. While the PremedX study reported no benefits of administering oral lorazepam as a premedication on patient satisfaction,5 other studies have reported that premedication with midazolam before surgery and endoscopic procedures improves patient satisfaction.7 12 15

    Certain clinical interventions are beneficial for high-risk populations but not for the general population.16 Anxiety tends to be more common among women.17–19 Therefore, we conducted a randomised controlled trial to assess the effect of premedication with midazolam on patient satisfaction in women.

    Methods

    Study setting

    The study was performed at a tertiary care university hospital in Wonju, South Korea. This study is reported in compliance with the Consolidated Standards of Reporting Trials (CONSORT) guidelines.

    Participants

    All consecutive female patients aged 20–65 years who underwent elective surgery under general anaesthesia between 17 March and 18 August 2021 were considered for enrolment in this study. Exclusion criteria included having an American Society of Anesthesiologists (ASA) physical status classification of III or higher, body mass index (BMI) 30 or higher, diagnosed with an airway obstruction, contraindication to benzodiazepines, currently being medicated with either benzodiazepines or opioids, being pregnant, breast feeding, having Child-Turcotte-Pugh class C hepatic dysfunction, acute narrow-angle glaucoma, inability to communicate, cognitive disorder and inability to understand the written information about the trial or the informed consent form.

    Study protocol

    All participants received written information about the study on the day before surgery. Sufficient time was allowed for patients to learn about and understand the study before signing the informed consent form. Screening and enrolment were mainly conducted by one of the authors (YJ) under the supervision of the corresponding author. The day before surgery, an assessment of preoperative anxiety was conducted using the Korean version of the APAIS, which was previously reported by Kim et al.20

    Patients were randomly assigned (1:1) to either the intervention or control group using a sealed envelope system. A random allocation sequence was created by one of the authors (SWS) using R statistical software V.4.0.4 (R Core Team, Vienna, Austria).21 The corresponding author maintained the opaque envelopes containing the group allocation until they were opened by one of the authors (YJ) on the day of surgery.

    A dedicated nurse was informed about which group each patient was allocated to and prepared the trial drug (midazolam 0.05 mg/kg) or placebo (normal saline 0.01 mg/kg) in a standard 1 mL syringe, according to group allocation. The volume of placebo was equivalent to the volume of premedication because the concentration of midazolam was 5 mg/mL. The draw-up needle was replaced with a 1.5-inch long 25-gauge needle.

    Following arrival at the preoperative holding area and standard patient identification procedures, premedication or placebo was administered via intramuscular injection into the deltoid muscle on the non-dominant side by a second nurse who was blinded to group allocation. The surgical team and the attending anaesthesiologists were also blinded to group allocation but were able to access relevant information via an electronic order communication system if necessary for patient care.

    Following the standard anaesthesia monitoring procedure, oxygen was administered via a facial mask at a rate of 10 L/min for 3 min. Remifentanil infusion was commenced and maintained at a rate of 0.1–0.2 µg/kg×min. Propofol was injected 1.5 mg/kg based on ideal body weight for induction of anaesthesia. After loss of consciousness, desflurane was administered at 0.7–0.9 minimum alveolar concentration to constitute balanced anaesthesia. Rocuronium was administered as a neuromuscular blocker and endotracheal intubation was performed using a video laryngoscope from the initial attempt.

    Following surgery, the patient was transferred to the post-anaesthesia care unit (PACU) and after 20 min of recovery, pain was evaluated using an 11-point Numeric Rating Scale (NRS) with a score of 0–10. In accordance with the medical centre’s recovery protocol, the minimum recovery period following general anaesthesia was 30 min. Participants responded to this study’s questionnaire after 20 min of recovery and on postoperative day (POD) 1 (online supplemental file 1 and online supplemental file 2).

    Variables and assessments

    The primary outcome was overall satisfaction with the anaesthesia experience, which is either included as an item of various anaesthesia satisfaction questionnaires or used to validate them.22 23 The questionnaire also measured satisfaction with premedication, intraoperative anaesthetic service, postoperative pain, and willingness to receive the same anaesthesia service if needed. Patients were asked to respond according to a five-point Likert scale ranging from 0 to 4, which has been used in several studies to measure patient satisfaction.24–27 A response of 3 or 4 was defined as a positive response. The satisfaction levels of the intervention and control groups were then compared. A subgroup analysis of anxious patients, defined as those who had an APAIS score for anxiety (APAIS-A) of 11 or higher, was conducted.5 20

    The secondary outcomes were safety profile, duration of recovery, postoperative pain and administration of rescue antiemetics in the PACU. The safety profile was measured in terms of heart rate, blood pressure and oxygen desaturation on arrival at the preoperative holding area, on arrival at the operating room, and after 20 min the PACU. Perioperative adverse events such as reintubation or mortality during hospitalisation were recorded. Perioperative peripheral oxygen saturation <95% was defined as oxygen desaturation. Intraoperative hypotension was defined as a mean blood pressure of <60 mm Hg.

    Statistical analysis

    The original analysis was planned and performed assuming the primary outcome, Likert-scale responses, as a continuous variable. However, given that a Likert scale of 0–4 is discontinuous, more appropriate analytical methods were applied. Responses in the Likert scale format were converted to binary as described in ‘Variables and assessments’, and binary logistic regression analysis was considered an alternative analytic method. A power analysis was conducted, and the statistical power of the logistic regression analysis was 0.800. Accordingly, binary logistic analysis was adopted as the analytic method.

    R statistical software (V.4.1.2) was used for statistical analysis and visualisation.21 Binary logistic regression analysis was performed to analyse patient satisfaction. Two-way repeated-measures analysis of variance was used to identify statistically significant differences in blood pressure and heart rate between the groups.

    Pain scores and other continuous variables were compared using a t-test. Categorical variables were analysed using χ2 tests, unless otherwise stated. Statistical significance was set at p<0.05.

    Sample size

    We assumed that the variability of the primary outcome would be similar to that found in a prior study that used the same five-point Likert scale to determine patient satisfaction.25 Comparison of means was assumed at the time the study was planned, and at a least 10% difference was considered to be clinically significant. The alpha value was set to 0.05 and the beta value was set to 0.2, which meant that having at least 63 patients per group would be sufficient to represent the population and identify differences between the groups. The projected drop-out rate was assumed to be 10%. Therefore, 70 patients were enrolled in each group.

    Patient and public involvement

    Neither the patients nor members of the public were involved in the design and recruitment of the study. Trial results will be disseminated via peer-reviewed scientific journals or conference presentations and patients will not be notified individually.

    Results

    The CONSORT flow diagram of this study is shown in figure 1. One patient in the control group died of pulmonary thromboembolism on POD 1. One patient in the intervention group was later excluded during the data validation process because of a BMI>30. Baseline patient demographics and the types of procedures performed are presented in .table 1.

    View this table:
    Table 1

    Baseline characteristics

    Figure 1
    Figure 1

    Study flow diagram.

    The mean and SD of APAIS-A and APAIS score for information desire (APAIS-I) of the whole patient sample were 11.3±4.5 and 6.2±2.3, respectively. There was no statistical difference in the vital signs on arrival at the preoperative holding area between the intervention and placebo groups (table 2). The mean time interval between arrival at the preoperative holding area and arrival at the operating room was 15.3±7.5 min.

    View this table:
    Table 2

    Safety profile by group

    For the primary outcome, patients who received midazolam tended to be more satisfied than those who received placebo (percentage difference: 21.0%; table 3 and figure 2). Patients who received midazolam were more satisfied with premedication and pain control than those who received placebo; however, this difference was not statistically significant. Patients who received midazolam were more willing to receive the same anaesthesia service later, if needed, than patients who received the placebo, and this difference was statistically significant (figure 3).

    Figure 2
    Figure 2

    Overall satisfaction with the anaesthesia experience for (A) all patients and (B) anxious patients with APAIS score for anxiety ≥11. APAIS, Amsterdam Preoperative Anxiety and Information Scale.

    Figure 3
    Figure 3

    Patient responses regarding (A) satisfaction with premedication, (B) satisfaction with anaesthesia in the operating room, (C) satisfaction with postoperative pain control and (D) willingness to receive the same anaesthesia if needed.

    View this table:
    Table 3

    Patient satisfaction by group

    In the subgroup analysis of patients with anxiety, there was no statistically significant difference between the groups in terms of their age, BMI, ASA physical status classification, APAIS score and type of surgical intervention received (table 4). Compared with the general sample, in this subgroup, the intervention group was more satisfied overall than the placebo group (percentage difference: 24.0%; figure 2 and table 4).

    View this table:
    Table 4

    Characteristics and outcomes of the anxiety subgroup

    With regard to secondary outcomes, the assessment of time-treatment interactions showed no statistically significant differences in the heart rates and systolic, diastolic and mean blood pressures between the groups. The incidence of intraoperative hypotension was also similar between groups (table 5). One patient in the intervention group experienced oxygen desaturation (SpO2 94%) on arrival in the operating room. The intervention group had a slightly longer mean recovery duration; however, this difference was not statistically significant. The intervention group had significantly higher postoperative pain scores after 20 min of recovery. Postoperative pain scores on POD 1 and administration of rescue analgesic use in the 24 hours after surgery were similar in both groups. The number of patients rescue antiemetics was more than twice the number of patients in the placebo group.

    View this table:
    Table 5

    Secondary outcomes by group

    Discussion

    Patient satisfaction is gaining recognition as an important healthcare outcome that represents the quality of healthcare from a patient perspective.28 The preoperative management of surgical patients should be conducted in consideration of patient satisfaction.29 Patient satisfaction with anaesthesia is determined by various factors, such as patient demographics, intraoperative awareness and quality of recovery.30

    In this study, among women undergoing general anaesthesia, patients who received premedication with intramuscular midazolam were more satisfied with the anaesthesia experience than those who received premedication with placebo. This difference was even more pronounced in the patients with anxiety. Comparison of anxious patients with the rest of the intervention and control groups showed that premedication with midazolam had a protective effect against dissatisfaction with the anaesthesia experience caused by preoperative anxiety.

    Midazolam is the most frequently used benzodiazepine for premedication.31 Despite patients’ frequent concern about intraoperative awareness,1 32 the amnestic effect of midazolam is not associated with depth of sedation.33 34 The pharmacological properties of midazolam, including its anxiolytic and amnestic effects, make it suitable as a premedication for general anaesthesia to enhance the anaesthetic experience while minimising the risks of cardiopulmonary complications.

    No emergency airway intervention was required after the administration of midazolam. One patient in the intervention group experienced oxygen desaturation, however, the oxygenation levels normalised following the encouragement of deep breathing of ambient air. Heart rate, systolic blood pressure and mean blood pressure were lower in the intervention group than in the control group on arrival at the operating room. However, these differences were less than 10%. These differences were also observed in the PACU, but were not statistically significant.

    Midazolam is manufactured in aqueous form and can be uniformly absorbed when administered via intramuscular injection. This route has some benefits over oral and intravascular administration.35 Intramuscular administration offers a more rapid onset of anxiolysis than gastrointestinal administration, bypassing gastric factors and the substantial first-pass metabolism of the drug. Intramuscular injection can achieve effective anxiolysis comparable to that achieved through intravenous injection when vascular access is unavailable.

    Premedication practices can vary considerably depending on the protocol of the anaesthesiology department and the preferences of the anaesthesiologist.9 To minimise the risk of adverse events such as respiratory depression, some anaesthesiologists prefer not to administer premedication before transferring the patient to the operating room. However, premedication for highly anxious patients in the preoperative holding area with a rapid-onset agent can help reduce dissatisfaction with the anaesthesia experience. This intervention is found to be especially effective in patients who are expected to stay in the preoperative holding area for more than 15 min.8

    The intervention group had higher NRS-11 pain scores in the PACU than the placebo group. Frölich et al reported that the administration of midazolam increases short, intermittent, and sustained pain perception.36 In our study, higher pain scores were not always negatively correlated with patient satisfaction. These findings are supported by Pozdnyakova et al, who also reported that higher pain scores did not correlate with worse patient satisfaction.37 Patient satisfaction can be reduced when their expectations are not met. Therefore, providing appropriate and timely analgesia can minimise the reduction in patient satisfaction when the difference in pain scores is not substantial. The minimum difference required in the NRS-11 scores for determining a clinically significant difference in pain was reported to be 1.23,38 suggesting that the difference in the groups’ pain in this study was not clinically substantial.

    This study has some limitations. The target population was relatively small. We enrolled relatively healthy young adults and excluded obese patients and those with a medical history of airway obstruction. Furthermore, all patients were ethnically Korean; therefore, the generalisability of this study’s results is limited. However, it is worth noting that similar findings were reported in the ConCIOUS cohort.38

    Only patients undergoing general anaesthesia with a restricted range of drugs were enrolled in this study. Patient satisfaction with the anaesthesia experience can vary according to the anaesthetic method and drug regimen. Finally, the power of the subgroup analysis was insufficient. Thus, additional research is needed to confirm benefits of preoperative midazolam administration in subgroups of different surgeries.

    Conclusion

    Premedication with intramuscular midazolam before general anaesthesia on the day of surgery improved the satisfaction of women, with minimal risk of associated complications.

    Data availability statement

    Data are available on reasonable request.

    Ethics statements

    Patient consent for publication

    Ethics approval

    This study was approved approved by by the Institutional Review Board of Wonju Severance Christian Hospital (approval number: CR320166). Participants gave informed consent to participate in the study before taking part.

    References

    1. ↵
      1. Celik F,
      2. Edipoglu IS
      . Evaluation of preoperative anxiety and fear of anesthesia using APAIS score. Eur J Med Res 2018;23:41.doi:10.1186/s40001-018-0339-4pmid:http://www.ncbi.nlm.nih.gov/pubmed/30205837
      OpenUrlCrossRefPubMed
    2. ↵
      1. Bansal T,
      2. Joon A
      . Preoperative anxiety-an important but neglected issue: a narrative review. The Indian Anaesthetists' Forum 2016;17:37.doi:10.4103/0973-0311.195955
      OpenUrl
    3. ↵
      1. Székely A,
      2. Balog P,
      3. Benkö E, et al
      . Anxiety predicts mortality and morbidity after coronary artery and valve surgery--a 4-year follow-up study. Psychosom Med 2007;69:625–31.doi:10.1097/PSY.0b013e31814b8c0fpmid:http://www.ncbi.nlm.nih.gov/pubmed/17724254
      OpenUrlAbstract/FREE Full Text
    4. ↵
      1. Soltner C,
      2. Giquello JA,
      3. Monrigal-Martin C, et al
      . Continuous care and empathic anaesthesiologist attitude in the preoperative period: impact on patient anxiety and satisfaction. Br J Anaesth 2011;106:680–6.doi:10.1093/bja/aer034pmid:http://www.ncbi.nlm.nih.gov/pubmed/21414978
      OpenUrlCrossRefPubMedWeb of Science
    5. ↵
      1. Maurice-Szamburski A,
      2. Auquier P,
      3. Viarre-Oreal V, et al
      . Effect of sedative premedication on patient experience after general anesthesia: a randomized clinical trial. JAMA 2015;313:916–25.doi:10.1001/jama.2015.1108pmid:http://www.ncbi.nlm.nih.gov/pubmed/25734733
      OpenUrlCrossRefPubMed
    6. ↵
      1. Walker KJ,
      2. Smith AF
      . Premedication for anxiety in adult day surgery. Cochrane Database Syst Rev 2009;4:CD002192.doi:10.1002/14651858.CD002192.pub2pmid:http://www.ncbi.nlm.nih.gov/pubmed/19821294
      OpenUrlPubMed
    7. ↵
      1. Sun G-C,
      2. Hsu M-C,
      3. Chia Y-Y, et al
      . Effects of age and gender on intravenous midazolam premedication: a randomized double-blind study. Br J Anaesth 2008;101:632–9.doi:10.1093/bja/aen251pmid:http://www.ncbi.nlm.nih.gov/pubmed/18772216
      OpenUrlCrossRefPubMedWeb of Science
    8. ↵
      1. Nishiyama T,
      2. Nagase M,
      3. Tamai H, et al
      . Optimal administration time of intramuscular midazolam premedication. J Anesth 1995;9:11–14.doi:10.1007/BF02482027pmid:http://www.ncbi.nlm.nih.gov/pubmed/23839826
      OpenUrlPubMed
    9. ↵
      1. Kain ZN,
      2. Mayes LC,
      3. Bell C, et al
      . Premedication in the United States: a status report. Anesth Analg 1997;84:427–32.doi:10.1097/00000539-199702000-00035pmid:http://www.ncbi.nlm.nih.gov/pubmed/9024042
      OpenUrlCrossRefPubMedWeb of Science
    10. ↵
      1. Erkola O,
      2. Korttila K,
      3. Aho M, et al
      . Comparison of intramuscular dexmedetomidine and midazolam premedication for elective abdominal hysterectomy. Anesth Analg 1994;79:646–53.doi:10.1213/00000539-199410000-00006pmid:http://www.ncbi.nlm.nih.gov/pubmed/7943770
      OpenUrlPubMedWeb of Science
    11. ↵
      1. Toyota K,
      2. Sakura S,
      3. Saito Y, et al
      . The effect of pre-operative administration of midazolam on the development of intra-operative hypothermia. Anaesthesia 2004;59:116–21.doi:10.1111/j.1365-2044.2004.03601.xpmid:http://www.ncbi.nlm.nih.gov/pubmed/14725512
      OpenUrlCrossRefPubMedWeb of Science
    12. ↵
      1. Kwon WK,
      2. Choi ES,
      3. Kim JY, et al
      . The effect of midazolam premedication on patient satisfaction during fiberoptic bronchoscopy under patient-controlled sedation. Korean J Anesthesiol 2009;56:1–5.doi:10.4097/kjae.2009.56.1.1pmid:http://www.ncbi.nlm.nih.gov/pubmed/30625687
      OpenUrlPubMed
    13. ↵
      1. Boncyk C,
      2. Hess AS,
      3. Gaskell A, et al
      . Does benzodiazepine administration affect patient satisfaction: a secondary analysis of the ConCIOUS study. Br J Anaesth 2017;118:266–7.doi:10.1093/bja/aew456pmid:http://www.ncbi.nlm.nih.gov/pubmed/28100532
      OpenUrlCrossRefPubMed
    14. ↵
      1. Shin S,
      2. Park CH,
      3. Kim HJ, et al
      . Patient satisfaction after endoscopic submucosal dissection under propofol-based sedation: a small premedication makes all the difference. Surg Endosc 2017;31:2636–44.doi:10.1007/s00464-016-5276-0pmid:http://www.ncbi.nlm.nih.gov/pubmed/27743126
      OpenUrlPubMed
    15. ↵
      1. Bauer KP,
      2. Dom PM,
      3. Ramirez AM, et al
      . Preoperative intravenous midazolam: benefits beyond anxiolysis. J Clin Anesth 2004;16:177–83.doi:10.1016/j.jclinane.2003.07.003pmid:http://www.ncbi.nlm.nih.gov/pubmed/15217656
      OpenUrlCrossRefPubMedWeb of Science
    16. ↵
      1. Ioannidis JP,
      2. Lau J
      . The impact of high-risk patients on the results of clinical trials. J Clin Epidemiol 1997;50:1089–98.doi:10.1016/S0895-4356(97)00149-2pmid:http://www.ncbi.nlm.nih.gov/pubmed/9368516
      OpenUrlCrossRefPubMedWeb of Science
    17. ↵
      1. Badner NH,
      2. Nielson WR,
      3. Munk S, et al
      . Preoperative anxiety: detection and contributing factors. Can J Anaesth 1990;37:444–7.doi:10.1007/BF03005624pmid:http://www.ncbi.nlm.nih.gov/pubmed/2340614
      OpenUrlCrossRefPubMedWeb of Science
    18. ↵
      1. Kuzminskaitė V,
      2. Kaklauskaitė J,
      3. Petkevičiūtė J
      . Incidence and features of preoperative anxiety in patients undergoing elective non-cardiac surgery. Acta Med Litu 2019;26:93–100.doi:10.6001/actamedica.v26i1.3961pmid:http://www.ncbi.nlm.nih.gov/pubmed/31281222
      OpenUrlPubMed
    19. ↵
      1. González-Lemonnier S,
      2. Bovaira-Forner M,
      3. Peñarrocha-Diago M, et al
      . Relationship between preoperative anxiety and postoperative satisfaction in dental implant surgery with intravenous conscious sedation. Med Oral Patol Oral Cir Bucal 2010;15:e379–82.doi:10.4317/medoral.15.e379pmid:http://www.ncbi.nlm.nih.gov/pubmed/19767708
      OpenUrlPubMed
    20. ↵
      1. Kim MJ,
      2. Oh H-K,
      3. Lee KC, et al
      . Effects of an Internet-based informational video on preoperative anxiety in patients with colorectal cancer. Ann Surg Treat Res 2019;96:290–5.doi:10.4174/astr.2019.96.6.290pmid:http://www.ncbi.nlm.nih.gov/pubmed/31183333
      OpenUrlPubMed
    21. ↵
      1. R Foundation for Statistical Computing
      . R: A language and environment for statistical computing [program. Vienna, Austria, 2021.
    22. ↵
      1. Bauer M,
      2. Böhrer H,
      3. Aichele G, et al
      . Measuring patient satisfaction with anaesthesia: perioperative questionnaire versus standardised face-to-face interview. Acta Anaesthesiol Scand 2001;45:65–72.doi:10.1034/j.1399-6576.2001.450111.xpmid:http://www.ncbi.nlm.nih.gov/pubmed/11152036
      OpenUrlCrossRefPubMedWeb of Science
    23. ↵
      1. Capuzzo M,
      2. Gilli G,
      3. Paparella L, et al
      . Factors predictive of patient satisfaction with anesthesia. Anesth Analg 2007;105:435–42.doi:10.1213/01.ane.0000270208.99982.88pmid:http://www.ncbi.nlm.nih.gov/pubmed/17646502
      OpenUrlCrossRefPubMedWeb of Science
    24. ↵
      1. Fitzpatrick R
      . Surveys of patient satisfaction: II--Designing a questionnaire and conducting a survey. BMJ 1991;302:1129–32.doi:10.1136/bmj.302.6785.1129pmid:http://www.ncbi.nlm.nih.gov/pubmed/2043786
      OpenUrlFREE Full Text
    25. ↵
      1. Cho JS,
      2. Shim J-K,
      3. Na S, et al
      . Improved sedation with dexmedetomidine-remifentanil compared with midazolam-remifentanil during catheter ablation of atrial fibrillation: a randomized, controlled trial. Europace 2014;16:1000–6.doi:10.1093/europace/eut365pmid:http://www.ncbi.nlm.nih.gov/pubmed/24381332
      OpenUrlCrossRefPubMed
    26. ↵
      1. Lee C-W,
      2. Liu S-T,
      3. Cheng Y-J, et al
      . Prevalence, risk factors, and optimized management of moderate-to-severe thirst in the post-anesthesia care unit. Sci Rep 2020;10:16183.doi:10.1038/s41598-020-73235-5pmid:http://www.ncbi.nlm.nih.gov/pubmed/32999369
      OpenUrlPubMed
    27. ↵
      1. Hewson DW,
      2. Worcester F,
      3. Sprinks J, et al
      . Patient-maintained versus anaesthetist-controlled propofol sedation during elective primary lower-limb arthroplasty performed under spinal anaesthesia: a randomised controlled trial. Br J Anaesth 2022;128:186–97.doi:10.1016/j.bja.2021.09.038pmid:http://www.ncbi.nlm.nih.gov/pubmed/34852928
      OpenUrlPubMed
    28. ↵
      1. Chow A,
      2. Mayer EK,
      3. Darzi AW, et al
      . Patient-Reported outcome measures: the importance of patient satisfaction in surgery. Surgery 2009;146:435–43.doi:10.1016/j.surg.2009.03.019pmid:http://www.ncbi.nlm.nih.gov/pubmed/19715800
      OpenUrlCrossRefPubMedWeb of Science
    29. ↵
      1. Wijeysundera DN,
      2. Finlayson E
      . Preoperative evaluation. Miller’s Anaesthesia. 9th ed. Elsevier, 2020: 918–98.
    30. ↵
      1. Myles PS,
      2. Williams DL,
      3. Hendrata M, et al
      . Patient satisfaction after anaesthesia and surgery: results of a prospective survey of 10,811 patients. Br J Anaesth 2000;84:6–10.doi:10.1093/oxfordjournals.bja.a013383pmid:http://www.ncbi.nlm.nih.gov/pubmed/10740539
      OpenUrlCrossRefPubMedWeb of Science
    31. ↵
      1. Vuyk J,
      2. Sitsen E,
      3. Reekers M
      . Intravenous anesthetics. Miller’s Anaesthesia. 9th ed. Elsevier, 2020: 638–79.
    32. ↵
      1. Woldegerima YB,
      2. Fitwi GL,
      3. Yimer HT
      . Prevalence and factors associated with preoperative anxiety among elective surgical patients at University of Gondar Hospital. Gondar, Northwest Ethiopia, 2017. A cross-sectional study. International Journal of Surgery Open 2018;10:21–9.
      OpenUrl
    33. ↵
      1. Polster MR,
      2. Gray PA,
      3. O'Sullivan G, et al
      . Comparison of the sedative and amnesic effects of midazolam and propofol. Br J Anaesth 1993;70:612–6.doi:10.1093/bja/70.6.612pmid:http://www.ncbi.nlm.nih.gov/pubmed/8329251
      OpenUrlCrossRefPubMedWeb of Science
    34. ↵
      1. Sarasin DS,
      2. Ghoneim MM,
      3. Block RI
      . Effects of sedation with midazolam or propofol on cognition and psychomotor functions. J Oral Maxillofac Surg 1996;54:1187–93.doi:10.1016/S0278-2391(96)90348-1pmid:http://www.ncbi.nlm.nih.gov/pubmed/8859237
      OpenUrlCrossRefPubMedWeb of Science
    35. ↵
      1. Polania Gutierrez JJ,
      2. Munakomi S
      . Intramuscular Injection. In: StatPearls. Treasure Island (FL): StatPearls Publishing, 2021.
    36. ↵
      1. Frölich MA,
      2. Zhang K,
      3. Ness TJ
      . Effect of sedation on pain perception. Anesthesiology 2013;118:611–21.doi:10.1097/ALN.0b013e318281592dpmid:http://www.ncbi.nlm.nih.gov/pubmed/23314164
      OpenUrlCrossRefPubMedWeb of Science
    37. ↵
      1. Pozdnyakova A,
      2. Tung A,
      3. Dutton R, et al
      . Factors affecting patient satisfaction with their anesthesiologist: an analysis of 51,676 surveys from a large multihospital practice. Anesth Analg 2019;129:951–9.doi:10.1213/ANE.0000000000004256pmid:http://www.ncbi.nlm.nih.gov/pubmed/31206431
      OpenUrlPubMed
    38. ↵
      1. Kendrick DB,
      2. Strout TD
      . The minimum clinically significant difference in patient-assigned numeric scores for pain. Am J Emerg Med 2005;23:828–32.doi:10.1016/j.ajem.2005.07.009pmid:http://www.ncbi.nlm.nih.gov/pubmed/16291435
      OpenUrlCrossRefPubMedWeb of Science

    Supplementary materials

    • Supplementary Data

      This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.

    Footnotes

    • Contributors SWS: conceptualisation, methodology, validation, formal analysis, investigation, visualisation, writing-original draft, review and editing; YJ: methodology, data curation, investigation, project administration; HL: data curation, review and editing; JL: data curation, review and editing; KHL: conceptualisation, supervision, project administration, review and editing. KHL is responsible for overall content as the guarantor.

    • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

    • Competing interests None declared.

    • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.