Gender and pain upon movement are associated with the requirements for postoperative patient-controllediv analgesia: a prospective survey of 2,298 Chinese patients

  • Yuan-Yi Chia
  • Lok-Hi Chow
  • Chun-Chieh Hung
  • Kang Liu
  • Luo-Ping Ger
  • Pei-Ning Wang
Regional Anesthesia and Pain



To investigate prospectively the influence of patient characteristics upon, and the association of postoperative measurements with, the requirements for postoperative morphine and the assessment of resting pain and pain upon movement in Chinese patients.


From January 1998 to December 1999, patients receiving patient-controllediv morphine subsequent to general anesthesia and surgery at our institute (Kaohsiung Veterans General Hospital), were enrolled in the study. Demographic data (such as gender, age, weight, height and education level) and postoperative measurements, including pain scores at rest or during movement, sedation scores and morphine consumption, were recorded.


In total 2,298 patients were recruited. Females consumed significantly less morphine via patient-controlled analgesia (PCA) in the first three postoperative days than was the case for males (P < 0.05). Gender was the strongest predictor for postoperative morphine requirements. Postoperative pain upon movement was another effective predictor for morphine requirement (P < 0.05). Age, body height, body weight, education and operation sites were not associated with morphine consumption.


Gender and postoperative pain upon movement are the major factors influencing morphine requirement for patientcontrollediv morphine analgesia during the first three postoperative days in Chinese patients.

Les besoins d’analgésie iv auto-contrôlée sont liés au sexe du sujet et à la douleur au mouvement : une enquête auprès de 2 298 Chinois



Examiner prospectivement si les caractéristiques du patient, et l’association des mesures postopératoires des douleurs, influencent les besoins de morphine postopératoire et l’évaluation de la douleur au repos et lors de mouvement chez des malades chinois.


De janvier 1998 à décembre 1999, les patients qui ont reçu de la morphine iv auto-contrôlée, à la suite d’une opération sous anesthésie générale au Kaohsiung Veterans General Hospital, ont participé à l’étude. Les données démographiques (sexe, âge, poids, taille et niveau d’instruction) et les mesures postopératoires, incluant les scores de douleur au repos et pendant le mouvement, les scores de sédation et la consommation de morphine, ont été enregistrées.


Nous avons recruté 2 298 patients. Pendant les trois premiers jours postopératoires, les femmes ont utilisé significativement moins de morphine que les hommes (P < 0,05) au moyen de l’analgésie auto-contrôlée (AAC). La variable prédictive la plus significative de la consommation de morphine postopératoire a été le sexe du patient. La douleur postopératoire pendant le mouvement a été un autre prédicteur efficace (P < 0,05). L’âge, la taille, le poids, l’instruction et le type d’opération n’ont pas été significatifs pour la consommation de morphine.


Le sexe et la douleur postopératoire pendant le mouvement sont les principaux facteurs d’influence des besoins de morphine pour l’analgésie iv auto-contrôlée pendant les trois premiers jours postopératoires chez des sujets chinois.


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Copyright information

© Canadian Anesthesiologists 2002

Authors and Affiliations

  • Yuan-Yi Chia
    • 1
    • 6
  • Lok-Hi Chow
    • 3
    • 4
  • Chun-Chieh Hung
    • 1
    • 6
  • Kang Liu
    • 1
    • 6
  • Luo-Ping Ger
    • 2
  • Pei-Ning Wang
    • 5
  1. 1.Department of AnesthesiologyKaohsiung Veterans General Hospital, National Yang-Ming University, School of MedicineKaohsiung
  2. 2.Department of Medical Education and ResearchKaohsiung Veterans General Hospital, National Yang-Ming University, School of MedicineKaohsiung
  3. 3.School of MedicineGraduate Institute of Medical Science, National Defense Medical CenterTaipeiTaiwan
  4. 4.Department of AnesthesiologySchool of MedicineTaipeiTaiwan
  5. 5.School of MedicineNeurological InstituteTaipeiTaiwan
  6. 6.School of MedicineTaipei Veterans General Hospital and the National Yang-Ming UniversityTaipeiTaiwan

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