Chinese Medical Journal 2012;125(14):2499-2504 2499 Original article Clinical attitudes towards pain treatment post-orthopedic surgery: a multicenter study in Beijing WANG Zhi-qiang, ZHAN Si-yan, Marlene Fransen and LIN Jian-hao Keywords: post-operative; pain; orthopedics; prevalence; Beijing S Background Pain is a common post-operative complication. Incidence of pain directly affects patients quality of life in terms of patient physiology, psychology, and social characteristics. This study was to understand clinical attitudes with regards to Beijing surgeons, and patients attitude towards pain treatment after orthopedic surgery. Methods A -based cross-sectional and cluster sample survey of 40 s in Beijing was conducted, including 20 level III (tier three) and 20 level II (tier two) general s. Enrolled subjects completed a specifically designed interview-questionnaire. Results The prevalence of pain 2 weeks post-orthopedic surgery was high in Beijing (96.1%). Meanwhile, collected data indicated most subjects in Beijing suffered moderate to severe pain, 45.1% and 41.4%, respectively, post-surgery. And for the concern of patients before surgery, most subjects chose full recovery from surgery (78.6%), as well as, the pain after operation was 39.2% ranked the third. According to the data from the study, Tramadol use was more common in Level III s, where Somiton was preferred in Level II s. When it came to the education of pain before and after operation, more patients get educated before operation than after it. In our study, case physicians or attending physicians enacted education before and after surgery. Related to the sense of patients, among the surgeons preferring post-operative analgesia, 67.6% considered administration when receiving complaints of moderate level pain, 50.0% indicated they will terminate analgesic treatment once pain degree scale wise decreases to benign pain. Conclusions The majority of orthopedic patients experience post-operative pain. Identification of post-operative pain will facilitate future awareness on pain treatment and nursing care in Beijing s, with pain relief through regulated improvements in strategic pain management. urgical treatment is an important selection in treating orthopedic diseases, with post-operative pain being a common complication. Post-operative pain is a natural nociceptive physiological response to stimulus caused by surgery through tissue damage as well as disease related pathophysiological changes. Considering time duration of surgically related pain, classification of acute pain is directed. 1,2 Incidence of pain directly affects patients quality of life in terms of patient physiology, psychology, and social characteristics. Simultaneous to acute pain, patients also experience insomnia and depression. Additionally, post-operative pain may induce complicated hypertension, myocardial ischemia, wound hemorrhage, and other post-operative interrelated complications. Post-operative pain stimulus is transmitted through the nervous system, through the spinal cord to the dorsal horn in the central nervous system. Sympathetic neural stimulation in turn causes muscle contraction and vasoconstriction, leading to possible wound ischemia and metabolic imbalance, affecting wound healing. 3 Over the years, pain, post-operative pain especially, is a topic of interest in the international medical field, with some specialists adhering to pain being a fifth vital sign. 4 A common issue regarding surgical treatment worldwide is unsatisfactory post-operative pain management. According to a random sample survey of post-operative patients in America published in Anesthesia & Analgesia (2003), it was reported that all surgical patients received some form of analgesic treatment for post-operative pain, with 80% of the patients receiving analgesic treatment still complaining of pain 2 weeks post-operation, of which 86% reported moderate to severe pain. 5 Although no local publications have discussed similar incidence in China, clinical awareness and observations have been noted. Through a survey of 40 s in Beijing, China, regarding clinical attitude towards post-operative pain and treatment among orthopedic surgeons and orthopedic patients were assessed. An inclusive evaluation of post-operative pain awareness and attitude in level III and level II s was compared. Resulting data will provide evidence in the drafting of standards for DOI: 10.3760/cma.j.issn.0366-6999.2012.14.019 Arthritis Institute, People s Hospital, Peking University, Beijing 100044, China (Wang ZQ and Lin JH) School of Public Health, Peking University Health Science Center, Beijing 100044, China (Zhan SY) The George Institute for International Health, Sydney, Australia (Fransen M) Correspondence to: Dr. LIN Jian-hao, Arthritis Institute, People s Hospital, Peking University, Beijing 100044, China (Tel: 86-10-88326257. Fax: 86-10-88326257. Email: jianhao_lin@ yahoo.com)
2500 post-orthopedic or post-operative pain treatment. METHODS Surveyed subjects The surveyed population was a compilation of ized patients and doctors within the department of orthopedics. Inclusion criteria of patients: (1) 18 years or older; (2) Underwent orthopedic surgery within two weeks; (3) With or without chronic pain history at other sites; (4) an match with investigation. Inclusion criteria of doctors: (1) Doctors in the orthopeadic department of s selected; (2) Have the technical title of resident or higher; (3) Can match with investigation. Sampling method A sample size of 1200 ized orthopedic patients was selected based on post-operative pain prevanlence from previous published literature, 5 with an 85% response rate. The survey was conducted using a convenient sampling method with two designed steps. Sample unit (SU) was first confirmed before the selection of 40 s in Beijing, which were chosen from 80 Level III s and 128 Level II s, and were defined as sample unit: consisting of 20 Level III s and 20 Level II s. The classification of s as Level II or Level III was based on Beijing Health Bureau regulative standardizations. Meanwhile, Level II and Level III s come to serve as community s and university s separately in America. Cluster sampling 6 was conducted in the second round of selection. Within the orthopedic departments of the 40 chosen s, 30 patient subjects who had undergone orthopedic operations were selected at each, followed by a collection of basic clinical features and patient information. Cluster sampling 6 was also used to select orthopedic surgeon subjects. This investigative study was approved by the Peking University Health Science Center Ethics Committee and informed consent was obtained from all study participants (patients and surgeons alike). Survey method Five interview questionnaire facilitators were trained in a uniform standard manner, including being proficient in the questionnaires and unification of the query mode, due to probability of literacy and levels of understanding amongst survey subjects. All questionnaire information and forms were carefully explained and shared to enhance and maintain query unification and data standardaization. Questionnaire interviews were conducted at bed side or face-to-face in outpatient and office surroundings, including recruited patient and orthopedic surgeon subjects. For interview unification, the questionnaires were filled out by investigators after collecting related information. For example, as for the level of pain, patients were asked to make a mark on the visual analogue scale (VAS) measure ruler. And then the results were filled out in the questionnaires by investigators. No financial compensation was provided to participants and all subjects were recruited voluntarily. Surveyed subjects included a compilation of post-orthopedic patients of varying ages (the youngest being 18 years old, all subjects younger than 18 years were excluded in statistical analysis), and orthopedic surgeons of various ranks and professional statuses at the selected s. Survey questionnaires were based on the Post-operative Pain Therapy Assessment Questionnaire, 7 assessing various pain factors including: patient age, gender, vices, subjects for pre-operative concern and queries, degree and duration of post-operative pain (VAS Pain scale 8 and Wong-baker scale 9 ), attitude towards pain itself, and treatment modals of pain. The orthopedic surgeon questionnaire included the following parameters: surgeon age, professional qualifications, commencement of analgesic treatment time, analgesic selection and common side effects, and surgeon attitude towards the use of narcotics. Statistical analysis EpiData 10 software (EpiData Association, Denmark) was used for data entry, where double entry and consistency inspection were used. Analysis of subject participants were divided into two categories based on the level of, level III or II, with a constituent ratio analysis of questionnaire parameters based on the total number of responded and completed patient and surgeon surveys. RESULTS A total of 1200 post-orthopedic surgery patients (defined as patients having undergone orthopedic operation within 2 weeks before survey interview) were randomly selected from 40 s in Beijing. Among the 1200 patients recruited, 69 subjects were excluded from further participation in the study due to age (under 18 years), inability, or limited understanding of questionnaire items (Table 1). The remaining 1131 patients were recruited and surveyed. The study period was from March to August 2009. Patient characteristics (1131 patients) included 59.3% male ((44.2±17.6) years); 40.7% female ((55.5±18.1) years) patients. Smokers and drinkers made up 32.4% and 22.1% of subject population, respectively. Approximately, 45.6% of the recruited patient subjects originated from a rural background, while the remaining patients were from an urban population. Most patients approached were from middle- and low-income households, with only 7.6% comprising of high-income households. Analysis of medical service payments revealed that most patients at level III s were covered by basic medical insurance (39.6%), while a novel rural cooperative medical care system (NCMS) was more common in the level II s (47.5%).
Chinese Medical Journal 2012;125(14):2499-2504 2501 Table 1. Clinical features of orthopedic patients and orthopedic surgeons in Beijing Level III Level II Total Patients (n=588, %) Surgeons (n=180, %) Patients (n=543, %) Surgeons (n=152, %) Patients (n=1131, %) Surgeons (n=332, %) Age (Years) 18 39 35.4 71.6 34.6 67.1 35.0 69.6 40 54 24.0 26.7 28.7 27.6 26.3 27.1 55 40.6 1.7 36.6 5.3 38.7 3.3 Gender Male 56.6 97.8 62.2 93.4 59.3 95.8 Female 43.4 2.2 37.7 6.6 40.7 4.2 Professional experience (Years) 1 15 68.3 67.1 67.8 16 30 30.6 28.3 29.5 31 1.1 4.6 2.7 Professional title Resident surgeon 27.8 36.8 31.9 Attending surgeon 43.3 37.5 40.7 Associate professor 21.7 19.1 20.5 Professor 7.2 6.6 6.9 Habits Smoking 26.5 38.7 32.4 Drinking alcohol 18.5 26.0 22.1 Region/patients region Urban 66.7 82.2 41.1 31.6 54.4 59.0 Rural 33.3 17.8 58.9 68.4 45.6 41.0 Financial status (patient) * Low income 41.7 22.2 57.5 53.3 49.2 36.4 Medium income 47.6 70.6 38.3 46.7 43.1 59.6 High income 10.7 7.2 4.2 0 7.6 3.9 Form of payment NCMS 18.5 47.5 32.4 Basic medical insurance 39.6 21.5 30.9 Self paid 16.5 15.7 16.1 Public medical coverage 18.2 8.7 13.6 Commercial insurance 5.4 4.8 5.2 Others 1.7 1.8 1.8 WHO 3 level pain staging Yes 76.7 57.2 67.8 No 11.1 18.4 14.5 Not sure 12.2 24.3 17.8 Fifth vital sign Yes 34.4 34.2 34.3 No 30.0 30.9 30.4 Not sure 35.6 34.9 35.2 * According to individual average income per family, financial status was classified into three groups: <1800 RMB yuan, 1800 4500 RMB yuan, >4500 RMB yuan. 11 The number of eligible orthopedic surgeons who completed the questionnaires was 332 (Table 1). Of the interviewed orthopedic surgeons, 95.8% were male ((36.3±8.5) years) and 4.2% were female ((29.5±7.3) years); 67.8% had 1 15 years of professional experience and 29.5% were ranging from 16 to 30 years of professional practice. The remaining 2.7% had senior professional experience of 31 years or more. Regardless of the level, orthopedic surgeons included in the survey ranged from the largest number being attending surgeons to residents, followed by associate professors and professors, respectively. Some orthopedic surgeons were knowledgeable of the WHO 3 Step Ladder for Pain Management (67.8%), 14.5% were not aware, while 17.8% were not sure. Pain was considered a fifth vital sign in 34.3% of the selected s, which managed and monitored pain while 30.4% did not consider pain to be a priority sign, and 35.2% were not sure. Regardless of the selected level, trauma patients were the largest group at 65.2% (Table 2). Within the questionnaires, patients were allowed multiple choices for consideration. According to the selection ranking, the first concern was full recovery after surgery (78.6%) and the second was whether or not surgery would improve their conditions (59.9%). Consideration of post-operative pain took third place (39.2%) in regards to surgery related queries. In addition, 73.5% of the patient subjects interviewed answered they knew pain would occur after operation, but still insisted on surgery, and only 5% of patient subjects decided against surgery due to anxiety and pain considerations. Over 50% of the patient subjects complained of post-operative pain within 2 days post surgery. This outcome was more prominent in level II s compared to level III s (Table 2). In both level III and level II s, the degree of pain relations were 45.1% experiencing moderate pain (VAS 4 6 ponits) while 41.4% severe pain (VAS 7 10 points). A minor
2502 Table 2. Surgical classification, pre-surgical patient concerns, duration and most intense pain experienced after operation (%) Level III (n=588) Level II (n=543) Total (n=1131) Surgical classification Joint 22.6 10.1 16.5 Trauma 53.2 77.9 65.2 Spine 20.7 11.6 16.3 Tumor 3.4 0.4 2.0 Pre-surgical patient concerns * Surgical results (improvement) 60.7 59.1 59.9 Pain during surgery 28.7 28.2 28.5 Pain after surgery 37.9 40.5 39.2 Full recovery from surgery 79.6 77.5 78.6 Professional rehabilitation 19.7 8.5 14.3 treatment Do not know 1.2 2.8 1.9 Pre-surgical patient assumptions There will be no pain after surgery 19.0 11.2 15.3 There will be post-operative pain, 70.2 77.0 73.5 but patient still insists upon surgical treatment Fear of post-operative pain caused 5.4 4.4 5.0 patient to refuse surgery Not sure 5.3 7.4 6.3 Duration of pain Less than 2 days 48.8 62.2 55.3 2 5 days 31.5 26.2 28.9 5 8 days 9.5 4.4 7.1 8 11 days 3.2 3.1 3.2 11 14 days 1.5 1.3 1.4 More than 14 days 1.5 1.5 1.5 No pain 3.9 1.3 2.7 Degree of pain 7 10 (Severe pain) 38.3 44.8 41.4 4 6 (Moderate pain) 46.6 43.5 45.1 1 3 (Slight pain) 9.7 9.6 9.6 0 (No pain) 5.4 2.2 3.9 * Patients may be concerned with more than one issue. percentage of 2.7% denied post-operative pain. Pain degree varied according to level; level III orthopedic patient surveys indicated that a majority of patients complained of moderate pain (46.6%), while severe pain was prominently presented (44.8%) (Table 2). Analysis of analgesic treatment and pain association indicated that a majority of patients recalled that pain medication was prescribed or ordered by their servicing attending physician (94.7%). While an overlap of patients indicated anesthesiologists (21.6%) and pain specialists (2.4%). Such an occurrence was in no relationship to level difference. After prescribed analgesics, 82.8% patients with post-operative pain complied of the medical regimen. With regards to administration time of analgesic treatment, 77.1% of orthopedic surgeons indicated their post-operative preference, with only 22.9% advocating preoperative analgesic treatment. Considering the larger majority preferring post-operative analgesia, 67.6% considered administration when receiving complaints of moderate level pain, 50.0% indicated they will terminate analgesic treatment once pain degree decreases scale wise to benign pain. Patients receiving post-operative analgesia, when asked about the specific medications received, 63.2% could not identify the name of the medication received. During the survey, Tramadol use was more common in level III s, where Somiton was preferred in level II s. An interesting observation indicated that level III prescription of paracetamol and other first line agents in systemic treatment using nonsteroidal anti-inflammatory drugs (NSAIDs) was zero, and only a slightly higher rate of 4.1% in level II. Of all patient subjects receiving pain treatment, 25.2% experienced adverse reactions, presenting with nausea, dizziness and drowsiness as common complaints (Table 3). Regardless of adverse effect considerations, most orthopedic surgeons (96.4%) supported analgesic treatment in in-patient surroundings with only 58.1% of surgeons agreeing to continued analgesic treatment upon discharge (out patient). Post-operative analgesic treatment patient who indicated high satisfaction were 19.3% and satisfaction were 75.7%. Only 3.4% of subjects were dissatisfied and 0.3% was very dissatisfied, with remnant pain. Table 3. Analgesics and side effects (%) Level III (n=479) Level II (n=457) Total (n=936) Analgesics Unknown 55.5 71.3 63.2 Morphine 2.1 3.1 2.6 Pethidine 6.9 4.4 5.7 Oxycontin 1.9 0 1.0 Fentanyl 6.7 2.6 4.7 Tramadol 11.3 1.7 6.6 Bucinnazine 1.5 1.5 1.5 Acetaminophen and 6.5 3.1 4.8 oxycodone co-formulation Paracetamol 0 4.1 2.0 Ibuprofen 2.9 8.5 5.7 Diclofenac 1.0 0.4 0.7 Celecoxib 2.7 0 1.4 Somiton 5.2 9.8 7.5 Midazolam 0 0.4 0.2 Phenobarbital 0.2 0 0.1 Diazepam 3.1 2.8 3.0 Others * 3.3 3.9 3.6 Side effects No side effects 77.0 72.4 74.8 Lethargy 5.2 5.2 5.2 Nausea 12.1 19.7 15.8 Constipation 2.9 3.5 3.2 Somnolence 3.8 4.4 4.1 Dizziness 7.3 3.3 5.3 Vomiting 3.3 6.1 4.7 Abdominal discomfort 2.1 1.1 1.6 Pruritis 1.3 0.9 1.1 Mood changes 0.8 0.7 0.7 Others 1.0 0.4 0.7 * Including the analgesics known by patients but were not included in the questionnaires.
Chinese Medical Journal 2012;125(14):2499-2504 2503 Table 4. Patient and surgeon concerns: narcotics (%) Level III Hospital Level II Hospital Total Patients (n=588) Surgeons (n=180) Patients (n=543) Surgeons (n=152) Patients (n=1131) Surgeons (n=332) Not concerned 57.1 16.1 66.5 10.5 61.6 13.6 Side Effects 28.1 70.0 20.6 71.7 24.5 70.8 Addiction 19.2 46.1 20.8 61.8 20.0 53.3 Interfere with disease progression? * 5.8 6.1 4.8 7.9 5.3 6.9 Increase social burden 13.3 17.8 15.4 Increase in medical costs 4.6 5.0 2.4 6.6 3.5 5.7 Replaced by non-narcotic drugs 5.3 23.9 4.6 20.4 5.0 22.3 Relation to drug enforcement agency 5.0 4.6 4.8 issues Others 1.7 1.7 1.7 2.0 1.7 1.8 * Means: pain is a natural consequence of the disease process and helps patients monitor the progression of the disease. Considering pre-operative pain education and communications, tallying all data, 58.5% of patients received pain education before surgery: level III s standing at 57.3% and level II at 59.9%. Continuation of pain education was enfored even after surgery, as indicated by 35.5% of post-surgical patients. Out of the total 58.5% educated, 63.5% indicated the education to be efficient and beneficial. In both level II and III s, case physicians or attending physicians enacted education before and after surgery (86.9% and 89.0%, respectively). Chinese patients and surgeons due to cultural differences often carefully consider the benefits and risks of narcotic analgesia. Within the 5% requesting drug changes, 80.4% were concerned by and wanted to avoid adverse effects, while 39.3% were weary of addiction. Surgeon rates were somewhat opposite, with only a minority of the 13.6% considering adverse effects, and 70.8% focusing more on the beneficial functions of narcotic treatment (Table 4). DISCUSSION High prevalence of postoperative pain (96.1%) after orthopedic surgery, despite advanced modern post-operative treatment, developed medicine, and improved nursing care standards was highlighted through this investigational study. The degree of pain observed are moderate to severe, these results were uncorrelated to level (P >0.05). Comparing observed data from previous Apfelbaum s study published post-operative surveys, the prevalence of postoperative pain is higher (P <0.05). 5 However, similar pain degree distributions (moderate to severe) were observed between both Apfelbaum s study and Beijing study post-operative populations. We must not forget, pain is a subjective sensation, an emotion resulting from personal discomfort. High prevalence in China may be directly related to backward or insufficient pain management with regards to peri-operative pain, this is indicated by a difference observed between staging (level II and III), where treatment selection, and pain degree distribution is directly correlated. Chinese orthopedic patients were mostly concerned with full recovery after surgery, with concentration on whether surgical treatment would improve their condition. This was a significant difference compared to Apfelbaum s study results published in 2003, where the top two fear factors for American orthopedic patients were post-operative pain and improvement of condition through surgery. 5 From our observations, we see Chinese patients being more concerned and paying more attention to the disease itself, along with disease complications, rather than surgically related factors. Post-operative concerns were lower than Apfelbaum s study results. This event is demonstrated through patient recognition and knowledge of pain before and after surgery: our Chinese survey indicated, 73.5% of patients insisted upon surgical treatment despite their knowledge of post-operative pain, while 5% postponed or cancelled surgical procedures because of pain. However, in Apfelbaum s study results, 8% of patients put off surgery due to pain anxiety. 5 Chinese patients conclusively regard post-operative pain to be a normal occurrence, a natural progressive part of surgical treatment, thus leading to a lower rate of concern. In Beijing, orthopedic surgeons prefer analgesic treatment only after receiving patient complaints of moderate or exacerbating pain. Again, correlating to degree of pain, while the termination of such analgesic treatment caters to patient personal expectations and needs. Of the patient subjects interviewed, 63.2% of patients did not know the name of the analgesics received, indicating a lack of information in doctor-patient communication. On the other hand, patients should actively become involved in their treatment regimen, paying more attention to treatment as well instead of disease related effects. Treatment compliance should be encouraged, however at the same time carefully balancing the difference between blind obedience. In Apfelbaum s study results NSAIDs were still mainstream considerations, such as cetaminophen with codeine or acetaminophen alone, for in-patient treatment. 5 But in China, level III prescription of paracetamol and other first line agents in systemic treatment using NSAIDs was zero, and a slightly higher ration by only 4.1% was found in level II. Narcotics were mostly used. The use of narcotics in analgesic treatment, poses a sensitive culturally related issue in China. Most patients did not worry about narcotics related side effects, instead agreeing to narcotic treatment for their post-operative
2504 pain; however 5% of patients requested alternative treatment, of which 80.4% were mainly concerned with related side effects including addiction possibilities. However, in the Apfelbaum s study, 72.0% of patients expected a non-narcotic drug to replace narcotic drug treatment, of which 49.0% again were concerned of side effects, and of which 18% with inherent addiction wished to seek relief from addiction. 5 Physician concerns were actually greater than patient reactions regarding the use of narcotics in analgesic treatment (P <0.05). The difference was analyzed to be as follows: firstly, due to insufficient understanding of narcotic drug use, patients do not worry about its side effects, but do not know what should I be worried about narcotic drug? ; second, it is blind to obey, Chinese patients do not actively participate in their treatment program. Patients sometimes simply listen to doctors, assuming they themselves do not need to know the details. Patient education is a major part of pre-operative preparations. Enhanced knowledge and awareness increases patient rights awareness involving their medical services and treatments. Our survey included questions regarding pain education before and after surgery; survey results indicated 58.5% of orthopedic patients received some form of education regarding post-operative pain before their procedure. In the Apfelbaum s study, the rate was up to two thirds (P <0.05). 5 Physicians were the main educators in Beijing s as opposed to nurses in Apfelbaum s study results. 5 Therefore, without regard towards prevalence or educating figure, pain education development and improvement should be a priority. Our survey indicated 63.5% of patients supported education to be beneficial, with a strong demand for further information and improvement. Several characteristics of the Beijing Post-operative Pain Study should be noted. First, a rigorous sampling strategy was utilized and the response rate was excellent (the response rate of patients was 91%). In the s, the most common reason for declining participation was lack of time. Meanwhile, when the interview was in progress, daily treatment and feeling ill were the main reasons for blocking the survey. This survey was conducted from March to August 2009, with accounted decreased accuracy with prolonged investigation time. However, preconceived notions and treatment options are not readily interchangeable; hence a stable five month period was ensured. Survey results were objective, without any interviewer or investigator interference. Patients recruited were post-orthopedic surgery patients with post-operative pain (within 2 weeks) at the time of survey interview, hence acquitting was highly prevalent. Patients were discharged 2 weeks after surgery. 5 If prolonged follow-up was allowed, further analysis and comparison between outpatient and inpatient pain could be performed, presenting further evidence to support our conclusions. The 40 Beijing s selected are only representative of same level s with similar hardware and conditions. However, if national representation was to be considered, a larger multicenter sampling number and scheme is required. Post-operative pain among orthopedic patients was a prominent observation. Hopefully through such investigations of prevalence, concept awareness and prioritization may allow for clinical experience analysis and summary, to develop a guide for future post-operative pain treatment and post-operative nursing management. 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(Received November 24, 2011) Edited by HAO Xiu-yuan