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© 2002 American Society for Clinical Oncology Practices and Attitudes of Japanese Oncologists and Palliative Care Physicians Concerning Terminal Sedation: A Nationwide SurveyByFrom the Seirei Hospice, Seirei Mikatabara Hospital, Hamamatsu; Psycho-Oncology Division, National Cancer Center Research Institute East, Kashiwa; and Psychiatry Division, National Cancer Center Hospital, Tokyo, Japan. Address reprint requests to Yosuke Uchitomi, MD, PhD, Psycho-Oncology Division, National Cancer Center Research Institute East, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577, Japan; email: yuchitom@ east.ncc.east.jp.
PURPOSE: To clarify the frequency of practice of sedation therapy for terminally ill cancer patients and to identify physicians’ attitudes toward sedation. METHODS: Questionnaires were mailed to 1,436 Japanese oncologists and palliative care physicians with a request to report their practice of and attitudes toward palliative sedation therapy. RESULTS: A total of 697 physicians returned questionnaires (response rate, 49.6%). Use of mild, intermittent-deep, or continuous-deep sedation for physical and psychologic distress was reported by 89% and 64%, 70% and 46%, and 66% and 38%, respectively. In vignettes in which physicians were asked whether they would use sedation for a patient with refractory dyspnea or with existential distress, 14% and 15%, respectively, chose continuous-deep sedation as a strong possibility. Those physicians less confident with psychologic care and with higher levels of professional burnout were more likely to choose continuous-deep sedation. In vignettes in which they were asked whether they use sedation for a patient with depression or delirium, 39% and 31%, respectively, considered psychiatric treatment to be a strong possibility, and 42% and 50% regarded continuous-deep sedation as a potential treatment option. Physicians less involved in caring for the terminally ill and less specialized in palliative medicine were significantly less likely to choose psychiatric treatment. CONCLUSION: Sedation is frequently used for severe physical and psychologic distress of cancer patients. Physicians’ clinical experiences with the terminally ill and their levels of professional burnout influence the decisions. Training and education for physicians in regard to end-of-life care and valid clinical guidelines for palliative sedation therapy are necessary.
END-OF-LIFE ISSUES in terminally ill patients have been actively discussed during the past decade. An increasing number of studies from Western countries have demonstrated that a considerable number of physicians have performed physician-assisted suicide (PAS), or euthanasia,1-6 and that physicians’ decisions about the end-of-life treatment are influenced not only by the patient’s condition but also by the physicians’ characteristics, such as their religion, specialty, confidence with symptom management, clinical experience in caring for the terminally ill, and degree of professional burnout.7-17 Sedation for symptom relief in the terminal stage has recently become a focus of strong controversy from an ethical and medical standpoint.18,19 Several studies have shown that approximately 10% to 50% of cancer patients require sedation for severe physical or emotional distress in their final days.20-23 Although the inconsistency in definitions of sedation and the heterogeneous nature of patients’ backgrounds make it difficult to interpret the wide variation in the reported frequency of sedation, some authorities suggest that physicians may apply different criteria for palliative sedation therapy and that sedation might be used inappropriately for intrinsically manageable conditions.24,25 In Japan, as in many Western countries, end-of-life issues, including sedation, are among the most actively discussed topics.21 Despite this, there has been no large systematic survey of physicians’ practices and attitudes toward sedation therapy in palliative care settings. In this nationwide survey, we have attempted to clarify the practices and attitudes of Japanese oncologists and palliative care physicians concerning palliative sedation therapy and to identify the factors that contribute to their clinical decisions.
Respondents We selected potential respondents from two sources. One source was a list of physicians from the Zenkoku Gan Seijinbyo Senta Kyogikai, a nationwide association of medical centers for cancer and adult disease. We used this source to obtain a sample of oncologists. The other source was a list from the Japanese Association of Hospice and Palliative Care Units that included all physicians working at palliative care units approved as formal members of the association. This list was used to obtain a sample of palliative care physicians. The inclusion criteria were (1) being an attending physician whose specialty was primarily responsible for care of terminally ill cancer patients, (2) having actual experience in oncology or palliative care, and (3) being unaffiliated with this study project. The Japanese Association of Hospice and Palliative Care Units and 26 institutions from a total of 27 hospitals that belonged to the Zenkoku Gan Seijinbyo Senta Kyogikai approved the study. In February 2000, the questionnaire was mailed to eligible physicians. The cover letter explained that this survey was confidential and anonymous. Consent to participate was indicated by the completion and return of the questionnaire. To identify nonrespondents, we instructed recipients to return an enclosed reply postcard separately from the completed questionnaire. A second questionnaire was mailed to physicians who had not returned the reply postcard by 4 weeks after the initial mailing.
Questionnaire The respondents were thereafter asked to identify their treatment choices for four brief vignettes on a 4-point Likert-type scale (unthinkable, difficult to consider, a possibility, and a strong possibility). Cases 1 and 4 were used to assess physicians’ attitudes toward patients with refractory physical and psychologic distress. In these presentations, a fully informed, competent, and nondepressed patient with terminal cancer requested active assistance to hasten death or complete sedation until death because of intolerable dyspnea (case 1) and existential distress (case 4) refractory to optimal medical and psychologic care. Cases 2 and 3 were used to evaluate physician attitudes toward patients with the desire for death and intrinsically treatable psychiatric disorders: depression (case 2) and delirium (case 3). In case 2, a markedly depressed patient with advanced cancer requested assistance to hasten death or complete sedation until death because of a sense of meaninglessness and severe malaise that was disproportionate to their physical condition. In case 3, a cancer patient who had been in a stable state suddenly developed delirium and expressed an ambiguous plea for early death. Independent evaluations by four consultation-liaison psychiatrists confirmed that the patients in cases 2 and 3 had intrinsically treatable psychiatric disorders and would be best managed psychiatrically rather than by sedation. To make comparisons easy, it was hypothesized in all four cases that the family supported the patient’s decision. Also, to provide valid information about the patient’s physical condition, prognostic factors identified by empirical studies (performance status, dyspnea, appetite, edema, state of consciousness)26,27 were presented with a clinical survival prediction of less than 3 weeks if no interventions were attempted in all vignettes. The prepared treatment options were (1) palliative care without intentional sedation, (2) psychiatric treatment without intentional sedation, (3) mild sedation with opioids, (4) mild sedation with psychotropics, (5) intermittent-deep sedation, (6) continuous-deep sedation, and (7) PAS/euthanasia. Finally, respondents were requested to complete the Maslach Burnout Inventory, which measures three components of the burnout syndrome: emotional exhaustion, depersonalization, and lack of personal accomplishment.28 The psychometric properties of the Japanese version had been assessed in another study,29 and the internal consistency of the subscales in the sample in this study was acceptable (Cronbach’s alpha coefficients, 0.68 to 0.88).
Definitions Because the terms sedation, PAS, and euthanasia can be ambiguous, they were replaced throughout the survey by descriptive phrases. For instance, terminal sedation, which has been described in several studies25,31 and corresponded to continuous-deep sedation in this study, was paraphrased in the questionnaire as continuous administration of sedatives or opioids to the point where the patient almost or completely loses consciousness, with the primary aim that the patient does not experience suffering. Similarly, psychiatric treatment without intentional sedation was differentiated from mild sedation with psychotropics in terms of presence or absence of physician intention to stimulate or allow the patient’s somnolence: the former was expressed in the questionnaire as psychiatric evaluation, treatment, and psychologic care without medical treatments that intentionally reduce the patient’s level of consciousness, and the latter was expressed as the administration of sedatives to the point where the patient is somnolent, with the primary aim that the patient does not experience suffering.
Statistical Analyses To explore the determinants of physicians’ attitudes toward palliative sedation therapy, we first used univariate analyses to screen the potential contributing factors to physicians’ attitudes: physician characteristics, degree of involvement in end-of-life care, confidence with symptom management, confidence with psychologic care, physicians’ preference for their own end-of-life care, strength of religious belief, and the burnout score. Multiple logistic regression analyses were then performed using all significant predictor variables that had been revealed by univariate analyses (P < .20) as independent variables in a backward elimination fashion. Because physician specialty highly correlated with the level of involvement in end-of-life care, only an involvement in the end-of-life care subscale was entered into the equations. For comparisons, the respondents were classified into two groups according to their responses to each vignette. In cases 1 and 4, physicians who chose continuous-deep sedation as a strong possibility were compared with those who did not. In cases 2 and 3, physicians who chose psychiatric treatment without intentional sedation as a strong possibility were compared with those who did not.
Univariate analyses were performed using the Mann-Whitney U-test, the
Characteristics of Physicians Of the 1,436 physicians to whom questionnaires were mailed, 550 returned them within 1 month, and 179 returned them after a reminder. Because 32 responses did not meet the eligibility criteria, 697 responses were ultimately analyzed (effective response rate, 49.6%; 697 of 1404). The responses were obtained in 87 (67%) of 130 physicians working at hospices or palliative care units and from 560 (43%) of 1,306 physicians at cancer centers or general hospitals (missing data on 50 physicians). The characteristics of the physicians are summarized in Table 1.
Although a second questionnaire was mailed to 73 physicians who had returned the original questionnaire because of a technical error, we decided to analyze all responses together because of our inability to identify the senders, the estimated small number of duplicate responses, and findings for all of the responses that were consistent with the analyses of the initial data (n = 550).
Practice of Palliative Sedation Therapy
Opinions Concerning Palliative Sedation Therapy On the other hand, 37% (n = 260) agreed that palliative sedation therapy was often associated with the risk of shortening patient life, and 17% (n = 119) stated that sedation was practically indistinguishable from acts to hasten death. Also, 48% (n = 332) regarded accurate determination of medical indications for palliative sedation therapy as difficult, and 25% (n = 175) recognized that there was a high risk of sedation being performed inappropriately.
Attitudes Toward Palliative Sedation Therapy in Vignettes
Factors That Contributed to Physicians’ Decisions The physicians who chose continuous-deep sedation as a strong possibility in cases 1 and 4 were less confident with psychologic care, were more likely to prefer symptomatic treatment for themselves, and demonstrated higher levels of emotional exhaustion and depersonalization (Table 3). By multivariate analyses, the independent determinants for physicians’ decisions to choose continuous-deep sedation were greater preference of symptomatic treatment for their own end-of-life care (odds ratio, 1.53; 95% confidence interval, 1.07 to 2.20; P = .021) and higher levels of emotional exhaustion (odds ratio, 1.02; 95% confidence interval, 1.01 to 1.04; P = .014) for case 1; and higher levels of emotional exhaustion (odds ratio, 1.02; 95% confidence interval, 1.00 to 1.04; P = .060) for case 4.
The physicians who chose psychiatric treatment as a strong possibility in cases 2 and 3 were significantly more involved in end-of-life care, were more likely to have specialized in palliative medicine, had greater confidence with symptom management, had shorter experiences of oncology, were younger, were more religious, and demonstrated higher levels of personal accomplishment (Table 4). Multivariate analyses revealed that less involvement in end-of-life care and greater age were independent determinants of physician preference not to choose psychiatric treatment as a strong possibility in cases 2 and 3 (Table 5). The confidence levels for symptom management and psychologic care were significantly different among palliative care specialists (n = 54), medical oncologists (n = 14), internists or internal medicine subspecialists other than medical oncologists (n = 250), and surgeons or surgical medicine subspecialists (n = 360): for symptom management, respectively, 3.73 ± 0.67 versus 3.44 ± 0.38 versus 3.00 ± 0.69 versus 2.95 ± 0.67, P < .01; for psychologic care, respectively, 3.49 ± 0.63 versus 3.11 ± 0.46 versus 2.81 ± 0.63 versus 2.83 ± 0.61, P < .01.
In addition, physicians who regarded PAS/euthanasia as a treatment option in any of the four cases were less involved in end-of-life care (odds ratio, 0.63; 95% confidence interval, 0.43 to 0.94; P = .023) and demonstrated higher levels of depersonalization (odds ratio, 1.07; 95% confidence interval, 1.01 to 1.12; P = .012).
To our knowledge, this is the first nationwide survey to systematically investigate clinical practices of and attitudes toward palliative sedation therapy for terminally ill cancer patients. One of the most important findings is the reported high frequency of palliative sedation therapy, in comparison with the much lower incidence of PAS/euthanasia: 66% to 89% of respondents reported using some form of sedation for severe physical distress, and 38% to 64% reported using some form of sedation for psychologic distress. Consistent with a previous survey of palliative care specialists in North America and the United Kingdom, in which 77% of the experts disclosed a clinical experience of deep sedation,31 our findings support that some types of sedation are needed as means of managing severe suffering just before death.18-25 This study, however, revealed the potential risk of inappropriate use of sedation for patients with potentially treatable psychiatric disorders. In the vignettes of patients with depression and delirium that were determined by experienced liaison psychiatrists to be intrinsically treatable, less than 40% of the physicians considered psychiatric interventions as a strong possibility, and approximately half approved of continuous-deep sedation as a potential option. On the other hand, palliative care specialists or the physicians with more experience in providing end-of-life care were more likely to choose psychiatric treatment. This suggests that insufficient training and clinical experience in end-of-life care, which results in confusion about psychiatric disorders and a normal part of the dying process and the underestimation of the efficacy of psychiatric treatment, is a main cause of hesitation in providing psychiatric treatment. Because many studies have stressed that depression and delirium are frequently underdiagnosed and undertreated despite their intrinsic treatability,32,33 training and education for inexperienced clinicians to screen treatable depression and delirium is of great importance. This study also revealed that those physicians who were less confident with psychologic care and demonstrated higher levels of emotional exhaustion were more likely to choose continuous-deep sedation for patients with refractory physical and psychologic distress. This finding supports the view presented by some experts that, in difficult situations in which patients ask for hastening of death, unskilled or emotionally exhausted physicians could apply sedation as an easy alternative to PAS and euthanasia.19,34 Two strategies can be valuable to resolve this undesirable possibility. First, because some empirical studies have identified occupational overload as a significant stimulator of burnout syndrome in oncologists,35 a systematic approach to reduce the physician’s emotional burden, such as encouragement of a team approach, increased available resources, and release from time constraints, is warranted. Second, the significant associations of physician specialty and their confidence with psychologic care may reflect differences in medical training. Because poor communication skills in managing patient existential distress are frequently identified as strong barriers to good end-of-life care,36 all physicians should receive systematic education about the skills needed to relieve the total suffering of cancer patients: how to restructure meaning, maintain achievable short-term goals, lessen uncertainty by an educational-cognitive approach, and conduct an honest dialogue on the nature of death.18 The lack of established guidelines for sedation therapy may have contributed to the highly inconsistent attitudes of physicians in this survey.25 Several practical guidelines for palliative sedation therapy have been recently proposed, and they commonly require (1) clarification of the treatment goal; (2) patient terminal illness; (3) presence of severe and refractory distress uncontrolled by all other measures, including psychologic and spiritual support; (4) informed consent obtained from patient and family; (5) team consent, consultation, or second opinion; and (6) explicit documentation.18,19,21,37,38 However, we consider the clinical utility of these guidelines to be limited, because, in addition to the inconstant definitions of sedation,30 they fail to validate how physicians can determine that symptoms are refractory. Although the guidelines often maintain that refractory symptom can be labeled only after all palliative treatments are tried, the medical indications and the estimated efficacy of each palliative treatment for a specified symptom have not been clarified. Thus, we believe that the lack of research evidence is a main cause of this unsatisfactory clarification, and that, to improve the inconsistency of physician attitudes toward palliative sedation therapy, well-designed clinical studies to prove the scientific validity of palliative sedation therapy are strongly required. This study has several limitations. First, because the response rate was relatively low, the results may not apply to the half of the study population that did not reply. Second, the absolute differences on score values of several determinants are small, although the results can be meaningfully interpreted and have useful clinical implications. Third, the cross-sectional nature of this study does not allow any conclusions to be drawn about the stability of physicians’ opinions. Finally, the technical error that led to duplicate mailing may have caused a bias, although we believe that its effect was minimal because the present results were confirmed by the analyses using the initial data. In conclusion, palliative sedation therapy is frequently performed for terminally ill cancer patients in Japan. Physicians’ decisions are influenced by their clinical experiences with the terminally ill and their degree of professional burnout. We emphasize the strong need for the training of physicians in end-of-life care, especially in regard to psychiatric and psychologic issues and scientifically validated guidelines for palliative sedation therapy. We do not believe that sedation should be considered standard medical care until optimal palliative and psychiatric care has been ensured for every patient.
The appendix is available online at www.jco.org. 
Research Edition Translation of the Maslach Burnout Inventory performed by Tatsuya Morita, MD, on November 24, 1999. Translated and reproduced by special permission of the publisher, Consulting Psychologists Press, Inc, Palo Alto, CA from Maslach Burnout Inventory, Human Services Survey by Christina Maslach and Susan E. Jackson. Copyright 1986 by Consulting Psychologists Press, Inc. All rights reserved. Further reproduction is prohibited without the publisher’s written consent.
Supported in part by grant no. 9-31, a Grant-in-Aid for Cancer Research, and the Second Term Comprehensive 10-Year Strategy for Cancer Control from the Ministry of Health and Welfare, Tokyo, Japan. We thank Yasuo Shima, MD, Masatoshi Kawase, MD, Kenji Nagayama, MD, Shuzo Morimoto, MD, and Kenji Nomura, MD, for their helpful comments and Yurie Sugihara, BA, for technical assistance.
Y.S. was awarded a Research Resident Fellowship from the Foundation for the Promotion of Cancer Research, Japan.
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Copyright © 2002 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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ABSTRACT
INTRODUCTION
2 test (Fisher’s exact methods), and the Kruskal-Walliss test, where appropriate. All analyses were performed with the Statistical Package for the Social Sciences (v 9.0; the SPSS Japan Inc, Tokyo, Japan). 
