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ORIGINAL ARTICLE
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Effect of preoperative anxiety on postoperative pain in patients undergoing elective lower-segment cesarean section under spinal anesthesia: A cross-sectional study in South India


1 MBBS Student, ESIC Medical College and PGIMSR, Chennai, Tamil Nadu, India
2 Assistant Professor, Department of Anaesthesiology, ESIC Medical College and PGIMSR, Chennai, Tamil Nadu, India

Date of Submission17-May-2022
Date of Decision01-Jul-2022
Date of Acceptance04-Jul-2022
Date of Web Publication17-Sep-2022

Correspondence Address:
Aswini Lakshminarasimhan,
epartment of Anesthesiology, ESIC Medical College and PGIMSR, KK Nagar, Chennai - 600 026, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jcrsm.jcrsm_39_22

  Abstract 


Background: Anxiety is often encountered but overlooked in patients undergoing elective surgery. Anxiety may influence the perception of postoperative pain which is one of the major concerns for all patients. This study aimed to evaluate the effect of preoperative anxiety on postoperative pain and to find if any relation exists between demographic variables and anxiety in cesarean patients.
Methodology: One hundred and twelve patients undergoing elective cesarean section under spinal anesthesia were evaluated for preoperative anxiety on the day before surgery using the Amsterdam Preoperative Anxiety and Information Scale questionnaire-based face-to-face interview, and postoperative pain was recorded every 6 h after surgery for 24 h using the Visual Analog Scale (VAS).
Results: The prevalence of preoperative anxiety in the study subjects was 36%. The need for high information was 22%. The mean for anesthesia-related anxiety, information desire component, combined anxiety score, and VAS scores was 4.21 ± 2.63, 3.23 ± 2.15, 8.72 ± 4.60, and 5.30 ± 1.86, respectively. Postoperative pain was found to be correlating with higher levels of preoperative anxiety (r = 0.25, P < 0.01). Information desire component was found to have a positive, moderate, and significant correlation with anxiety score (r = 0.49, P < 0.01). No statistically significant relationship was found between sociodemographic characteristics and preoperative anxiety.
Conclusion: This study demonstrated a positive and statistically significant correlation between preoperative anxiety and postoperative pain. Well-conducted randomized controlled studies are required to determine whether reducing anxiety before a surgery results in reduced postoperative pain response. Anxiety-reducing measures can be employed throughout the preoperative period in the surgical population to reduce postoperative pain in addition to analgesics.

Keywords: Anxiety, Amsterdam Preoperative Anxiety and Information Scale, cesarean section, pain, postoperative pain, preoperative anxiety



How to cite this URL:
Suresh Y, Lakshminarasimhan A. Effect of preoperative anxiety on postoperative pain in patients undergoing elective lower-segment cesarean section under spinal anesthesia: A cross-sectional study in South India. J Curr Res Sci Med [Epub ahead of print] [cited 2022 Oct 4]. Available from: https://www.jcrsmed.org/preprintarticle.asp?id=356212




  Introduction Top


Surgery is an event of dramatic significance for many patients which disrupt their physical, mental, economic, and professional life. Preoperative anxiety is a normal and anticipated response in all individuals undergoing major and minor surgeries. Anxiety is a psychological state of uneasiness that can be caused by internal or external threat of no particular origin, and can be linked to altered hemodynamics as a result of activation of sympathetic, parasympathetic, and endocrine systems.[1],[2] Anxiety begins right from the time the surgery is planned, reaches its peak when entering the hospital, and might extend even after surgery.[3] Among adults, the incidence of preoperative anxiety is 11% to 80%.[4] Although various scales do exist to evaluate the preoperative anxiety of patients, less attention is often paid to the patients' anxiety.[5] Physiologically, anxiety can alter a patient's vital signs. Psychological changes are individualized and reflect a person's baseline personality.[2] Preoperative anxiety has a plethora of postoperative effects on the patients, and the most problematic among them can be pain, which is also one of the most common complaints and fear of the patients.[6] Higher-than-normal levels of postoperative pain increase the dependence on analgesics and ameliorate the quality of life and patient satisfaction.[7] Therefore, there is a need to find the predictors of postoperative pain to enhance the quality of patient care.

Previous studies have shown that the pain threshold was lower with increased anxiety levels.[8] Some studies have shown that the impact of anxiety was different with different types of surgery.[9] In the last few years, studies have been conducted to find the relationship between anxiety before surgery and pain after surgery across the world.[10],[11],[12] We chose to conduct the study in patients undergoing cesarean section as the study population would be homogeneous because it is the most commonly performed surgery.

The primary objective of this study was to determine if any relation existed between preoperative anxiety and postoperative pain. The secondary objective was to determine if there was any relation between the sociodemographic characteristics and preoperative anxiety in elective cesarean section.


  Materials and Methods Top


This institutional-based cross-sectional study was conducted from October 2021 to December 2021 at a teaching hospital in South India. The study was approved by the Institutional Ethics Committee (IEC) of our institution (IEC/2020/1/12). The trial has been registered with the Clinical Trials Registry of India (CTRI/2021/10/037400). Written informed consent was obtained from all the participants of the study. Female patients undergoing elective lower-segment cesarean section under spinal anesthesia, belonging to the American Society of Anesthesiologists status II, between the ages of 20–40 years were included in the study. Patients on medications for chronic diseases, patients with known chronic pain disorders, and those with known psychiatric disorders such as generalized anxiety disorder, panic disorder, specific phobias, and social anxiety disorder were excluded from the study. The Amsterdam Preoperative Anxiety and Information Scale (APAIS) questionnaire-based face-to-face interview was conducted by the investigator on the day before surgery to assess the preoperative anxiety level of the patient. The questionnaire was translated to the local language of the patients and its linguistic validity was tested by back translating to English with the help of language experts. The questionnaire included all demographic details of the patients. APAIS is a validated questionnaire that consists of three domains (anesthesia-related anxiety, surgery-related anxiety, and information desire component). Each domain consists of two questions making it a total of six questions. The maximum number of points for each question is 5. The APAIS is further subdivided into subscales: questions 1 and 2 together make up anesthesia-related anxiety or “sum A,” anxiety related to surgery or “sum S” is the sum of the scores of questions 4 and 5, and a combined anxiety score or “sum C” equals sum A + sum S. Therefore, the total scores of sum A and sum S are 10 each, and the maximum score for sum C (combined anxiety) is 20. Questions 3 and 6 contribute to the information desire domain of the APAIS, the maximum score of which is again 10. The response was elicited using the five-point Likert scale. The patients were asked to mark the number that shows their anxiety at that moment: 1 = not at all anxious, 2 = a little anxious, 3 = moderately anxious, 4 = very anxious, and 5 = extremely anxious. A score of ≥11 identifies patients with high anxiety. Concerning the information desire component, a score of 2–4 indicates no/little information requirement, 5–7 indicates moderate information requirement, and a score of 8–10 indicates high information requirement. The questionnaire is given in Appendix 1.

In the operating room, during surgery, anesthesia management was standardized for all the patients. All patients received spinal anesthesia with 2 ml of 0.5% hyperbaric bupivacaine. After surgery, the patients were shifted to the postanesthesia care unit (PACU), and the analgesic regimen was also standardized for all the patients. The regimen included intravenous paracetamol (15 mg/kg) every 6th h. Postoperative pain evaluation was done every 6 h after surgery for the first 24 h using the Visual Analog Scale (VAS) by the staff nurses in the PACU. VAS consists of a line with one end representing no pain and another end representing worst pain. The patients were asked to point to a position in the line that indicated their pain level at that moment. Patients complaining of severe pain (VAS >5) were given 100-mg tramadol intravenously as rescue analgesia.

Statistical analysis

The sample size was calculated using nMaster software (2.0). The correlation coefficient between anxiety and pain was used as the primary outcome measure to calculate the sample size. In a power analysis based on a 95% confidence interval with 80% power, considering preoperative anxiety and postoperative pain as correlation coefficients, a sample size of 93 was sufficient.[6] Expecting a dropout of 20%, a total of 112 patients were recruited. Mean with standard deviation and frequency with percentages were used to describe the continuous and categorical data, respectively. The correlation between preoperative anxiety and postoperative pain was calculated using Karl Pearson's correlation coefficient. To find the association between demographic variables and the combined anxiety and information desire component of patients, the Chi-square test was used. The time graphs and pie charts were presented using Microsoft Excel. The statistical analysis was done using IBM SPSS Statistics for Windows, version 21.0 ( IBM Corp., Armonk., N.Y., USA).


  Results Top


A total of 123 participants were recruited for the study. Eleven participants were excluded due to a lack of motivation to fill out the questionnaire and lack of informed consent. One hundred and twelve patients were included in the study [Figure 1]. The sociodemographic characteristics of the study sample are shown in [Table 1]. The prevalence of anxiety and the desire for high information is shown in [Table 2]. Out of the 112 participants, 40 people have been found to have high combined anxiety scores (36%) and 22% of them had a moderate-to-high information desire. The mean component-specific scores and their significance with anxiety scores are shown in [Table 3]. The mean for anesthesia-related anxiety, information desire component, combined anxiety score, and VAS scores was 4.21 ± 2.63, 3.23 ± 2.15, 8.72 ± 4.60, and 5.30 ± 1.86, respectively. Postoperative pain was found to be correlating with higher levels of preoperative anxiety (r = 0.28, P < 0.01). Information desire component was found to have a positive, moderate, and significant correlation with anxiety score (r = 0.49, P < 0.01) [Table 3]. The mean pain score was very low during the immediate postoperative period (2.46) and reached its peak 12 h after surgery (6.23) and then started to slightly reduce thereafter [Figure 2]. No statistically significant relationship was found between sociodemographic characteristics and preoperative anxiety [Table 4].
Figure 1: Strobe flow diagram

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Figure 2: Postoperative pain score

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Table 1: Sociodemographic characteristics of the study sample

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Table 2: Anxiety and Information desire scores in the study population

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Table 3: Component-specific scores and their relation with average pain score at the 12th h

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Table 4: Sociodemographic factors and their relation with preoperative anxiety and information desire

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  Discussion Top


The primary goal of this cross-sectional study was to evaluate preoperative anxiety using the APAIS scale in the most commonly performed cesarean surgery and its effect on postoperative pain. Anxiety is frequent in patients anticipating elective surgery, and it is usually less comprehended and considered a natural reaction.[1],[2] Preoperative anxiety may be recognized routinely during the evaluation of patients, and anxiety levels vary from patient to patient. Preoperative anxiety has been linked to increased perception of postoperative pain. Higher postoperative pain can cause many problems such as acute physiological stress, postoperative delirium, immobilization, infections, alterations in the sleep–wake cycle and hormonal disturbances, longer hospital stay, and financial burden.[2],[13] Reducing postoperative pain is, therefore, a key to decreasing the dependence on analgesics, to provide improved quality of life and patient satisfaction.[7]

Our study population included women who were posted for elective cesarean section under spinal anesthesia. Early recovery is especially critical for a cesarean patient as the mother needs to take care of the neonate immediately after surgery. According to researchers, unmanaged pain after a cesarean section negatively affected breastfeeding and infant care with a higher incidence of chronic pelvic pain, posttraumatic stress syndrome, and thromboembolism.[14],[15] Preoperative anxiety is a powerful predictor of initial postoperative pain, which in turn is a strong predictor of pain inward and pain at home.[16] Thus, there is paramount importance to reduce preoperative anxiety.

There are a wide range of reliable and validated questionnaires to evaluate anxiety such as the State-Trait Anxiety Inventory, Hospital Anxiety and Depression Scale, VAS, Amsterdam Preoperative Anxiety and Information Scale (APAIS), Anxiety Specific to Surgery Questionnaire (ASSQ), modified Yale Preoperative Anxiety Scale, Miller Behavioral Style Scale, and Somatosensory Amplification Scale. APAIS which has been used in our study is valid, reliable, easily employed, and less time-consuming instrument for assessing the level of preoperative anxiety and the need for information in different settings.[17],[18] Our study demonstrated that preoperative anxiety was present in 36% of the participants (40 out of 112) by taking a cutoff value of 11 or more. Previous studies have stated the prevalence of preoperative anxiety to be between 60% and 80%.[1],[19] Geographical variation in anxiety scores has also been demonstrated.[19],[20] Age, gender, socioeconomic status, educational status, type of surgery, knowledge of adverse effects, prior surgical and anesthesia experience, and type of personality are all factors to be considered and taken into account.[20],[21] Bradshaw et al.[13] have observed that younger patients had more anxiety preoperatively than the elderly. They have pointed out that elderly patients have an easier acceptance of reality and previous exposure to the health-care system.[13] A study conducted in Pakistan found that females had higher anxiety when compared to males.[1] We could not make such a comparison as our study included only the young women population. A cohort study done in Spain has found that patients with prior surgery and anesthesia experience were less anxious.[22] However, our study was unable to establish such an association which is also supported by the research conducted by Woldegerima et al.[20]

A relevant finding of our study was a positive correlation between information requirement and combined anxiety (r = 0.49, P < 0.01). According to Jawaid et al.,[1] 56% of the patients thought that if they had gotten more elaborate information regarding the procedure, their anxiety would have been reduced. Moerman et al.[22] have also suggested that more information is needed to reduce anxiety. One proven method of reducing information desire is by providing handouts containing an overview of what to anticipate in the operation room and during the recovery period, as done by Kalliyath et al.[17] in a study conducted in Kerala, India. Face-to-face education in addition to the handouts has been found to reduce anxiety levels before surgery.[23] Another salient and most important finding of the study is that the patient's preoperative anxiety correlated with their postoperative pain (r = 0.25, P < 0.01). The same relationship has been observed in foot nail surgery, hysterectomy, cesarean section, laparoscopic cholecystectomy, and rotator cuff repair surgery by various authors.[16],[24],[25],[26] Research with nonhomogenous study populations has also had identical findings.[13] Probable reasons for these findings could be because higher anxiety levels decrease the postoperative pain threshold, increase pain sensitivity, diminish treatment efficiency, and damage patients' physical and mental health.[16],[27] A study with rats demonstrated that anxiety activated the astrocytes in the anterior cingulate cortex region and induced chronic pain.[27] The most likely causes of anxiety related to anesthesia can be fear of death or waking up in the midway of the procedure, fear of pain during the intraoperative and postoperative period, nausea and vomiting, fear of needle and intervention, etc., The fear of postsurgical pain was found to be the most common cause.[18] Although all of our patients have had their preanesthetic visits, their anxiety was still quite high. It could have been because the patients did not receive proper counseling preoperatively. No correlation was found between surgery-related anxiety and pain. In our study, 23% of the participants experienced severe pain during the initial 24 h after surgery. Surprisingly, the pain was very low during the immediate postoperative period and reached its peak within 12 h of surgery. The probable reason could be the wearing off of spinal anesthesia. Nonpharmacological methods such as meditation, education about coping mechanisms, interaction with the doctor, music therapy, acupuncture massage, aromatherapy, and relaxation techniques have proved to reduce anxiety and are easy to be implemented.[17],[23] Concerning information desire, the results of our study showed that 22% of the patients wanted more information (>4 points on the APAIS scale), and this was higher in patients with anxiety. Earlier studies have shown that 40%–80% of the patients had high information desire.[22] This very huge contrast might be because the cesarean section is the most common and well-known surgery among the general public. In addition, some authors have reported that patients with prior anesthetic and surgical experiences needed comparatively less information which was not observed in our study.[18]

Strengths of the study

The strength of this study is that validated and reliable scales were used in our study to measure anxiety and pain. To reduce the confounding factors, the patient population, surgical indication, and surgical method were all made homogeneous. Further, because the anesthetic management can influence pain outcome variables, the anesthetic management and the postoperative pain management regimen were standardized in this study. The study sheds light on the importance of assessing anxiety in surgical patients as a part of the preoperative anesthetic evaluation.

Limitations

The study's limitation is that the reasons for anxiety were not addressed. In this study, the questionnaire was administered by the investigator which could have contributed to investigator bias. Another drawback is that the study participants in the research were selected from a single location. As a result, the variation between geographical sites could not be explored. Finally, the operating surgeon and anesthesiologist were not the same for all the patients, which might have contributed to the anxiety.


  Conclusion Top


This cross-sectional study has found that preoperative anxiety influenced postoperative pain. Based on the findings of this research, we believe that well-conducted randomized controlled studies are required to determine whether reducing anxiety before a surgery results in reduced postoperative pain response. Furthermore, anxiety-reducing measures can be employed throughout the preoperative period in the surgical population to reduce postoperative pain in addition to analgesics.

Acknowledgments

We acknowledge the statistical help from Dr. Aruna Patil, Associate Professor of Biostatistics, ESIC Medical College and PGIMSR, Chennai.

This study was supported by the Short-Term Studentship (STS-2020) of the Indian Council of Medical Research (Reference ID: 2020-06663).

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.


  Appendix 1: Questionnaire Top


The Amsterdam Preoperative Anxiety and Information Scale

Not at all 1 2 3 4 5 Extremely

1. I am worried about the anesthetic □ □ □ □ □

2. The anesthetic is on my mind continually □ □ □ □ □

3. I would like to know as much as possible about the anesthetic □ □ □ □ □

4. I am worried about the procedure □ □ □ □ □

5. The procedure is on my mind continually □ □ □ □ □

6. I would like to know as much as possible about the procedure □ □ □ □ □

The subscales:

Anesthesia-related anxiety sum A = 1 + 2

Surgery-related anxiety sum S = 4 + 5

Information desire component = 3 + 6

Combined anxiety component sum C = sum A + sum S (1 + 2 + 4 + 5)

1 = not at all anxious, 2 = a little anxious, 3 = moderately anxious, 4 = very anxious, and 5 = extremely anxious

Visual Analog Scale





 
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Jawaid M, Mushtaq A, Mukhtar S, Khan Z. Preoperative anxiety before elective surgery. Neurosciences (Riyadh) 2007;12:145-8.  Back to cited text no. 1
    
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  [Full text]  
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    Figures

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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

 
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