No abstract

Chronic pain is a major source of suffering. It interferes with daily functioning, and often is accompanied by distress. Yet, in the International Classification of Diseases (ICD), chronic pain diagnoses are not represented systematically. The lack of appropriate codes renders accurate epidemiological investigations difficult and impedes health policy decisions regarding chronic pain. This hinders adequate financing of treatments for chronic pain patients, limiting access to multimodal care. In cooperation with the WHO, an IASP Working Group has developed a classification system that is applicable in a wide range of contexts, including pain medicine, primary care, and low-resource environments. Chronic pain is defined as pain that persists or recurs for more than three months. In chronic pain syndromes, pain can be the sole or a leading complaint and requires special treatment and care. In conditions such as fibromyalgia or nonspecific low back pain, chronic pain may be conceived as a disease in its own right; in our proposal, we call this subgroup 'chronic primary pain'. In six other subgroups, pain is secondary to an underlying disease: chronic cancer-related pain, chronic neuropathic pain, chronic secondary visceral pain, chronic posttraumatic and postsurgical pain, chronic secondary headache and orofacial pain, and chronic secondary musculoskeletal pain. These conditions are summarized as 'chronic secondary pain' where pain may at least initially be conceived as a symptom. Implementation of these codes in the upcoming 11 th edition of ICD will lead to improved classification and diagnostic coding, thereby advancing the recognition of chronic pain as a health condition in its own right.

Cesarean delivery rates continue to increase, and surgery is associated with chronic pain, often co-existing with depression. Also, acute pain in the days after surgery is a strong predictor of chronic pain. Here we tested if mode of delivery or acute pain played a role in persistent pain and depression after childbirth. In this multicenter, prospective, longitudinal cohort study, 1288 women hospitalized for cesarean or vaginal delivery were enrolled. Data were obtained from patient interviews and medical record review within 36 hours postpartum, then via telephone interviews 8 weeks later to assess persistent pain and postpartum depressive symptoms. The impact of delivery mode on acute postpartum pain, persistent pain and depressive symptoms and their interrelationships were assessed using regression analysis with propensity adjustment. The prevalence of severe acute pain within 36 hours postpartum was 10.9%, while persistent pain and depression at 8 weeks postpartum were 9.8% and 11.2%, respectively. Severity of acute postpartum pain, but not mode of delivery, was independently related to the risk of persistent postpartum pain and depression. Women with severe acute postpartum pain had a 2.5-fold increased risk of persistent pain and a 3.0-fold increased risk of postpartum depression compared to those with mild postpartum pain. In summary, cesarean delivery does not increase the risk of persistent pain and postpartum depression. In contrast, the severity of the acute pain response to childbirth predicts persistent morbidity, suggesting the need to more carefully address pain treatment in the days following childbirth.

The upcoming 11th revision of the International Classification of Diseases and Related Health Problems (ICD) of the World Health Organization (WHO) offers a unique opportunity to improve the representation of painful disorders. For this purpose, the International Association for the Study of Pain (IASP) has convened an interdisciplinary task force of pain specialists. Here we present the case for a reclassification of nervous system lesions or diseases associated with persistent or recurrent pain for ≥ 3 months. The new classification lists the most common conditions of peripheral neuropathic pain: trigeminal neuralgia, peripheral nerve injury, painful polyneuropathy, postherpetic neuralgia, and painful radiculopathy. Conditions of central neuropathic pain include pain caused by spinal cord or brain injury, post-stroke pain, and pain associated with multiple sclerosis. Diseases not explicitly mentioned in the classification are automatically captured in the residual categories of ICD-11. These conditions are either insufficiently defined or missing in the current version of the ICD despite their prevalence and clinical importance. We provide the short definitions of diagnostic entities for which we submitted more detailed content models to the WHO. Definitions and content models were established in collaboration with the Classification Committee of the IASP’s Neuropathic Pain Special Interest Group (NeuPSIG). Up to 10% of the general population experience neuropathic pain. The majority of these patients do not receive satisfactory relief with existing treatments. A precise classification of chronic neuropathic pain in ICD-11 is necessary to document adequately this public health need and the therapeutic challenges related to chronic neuropathic pain.

Chronic pain after tissue trauma is frequent and may have a lasting impact on the functioning and quality of life of the affected person. Despite this, chronic postsurgical and posttraumatic pain is underrecognised and, consequently, undertreated. It is not represented in the current International Classification of Diseases (ICD-10). This article describes the new classification of chronic postsurgical and posttraumatic pain for ICD-11. Chronic postsurgical or posttraumatic pain is defined as chronic pain that develops or increases in intensity after a surgical procedure or a tissue injury and persists beyond the healing process, ie, at least 3 months after the surgery or tissue trauma. In the classification, it is distinguished between tissue trauma arising from a controlled procedure in the delivery of health care (surgery) and forms of uncontrolled accidental damage (other traumas). In both sections, the most frequent conditions are included. This provides diagnostic codes for chronic pain conditions that persist after the initial tissue trauma has healed and that require specific treatment and management. It is expected that the representation of chronic postsurgical and posttraumatic pain in ICD-11 furthers identification, diagnosis, and treatment of these pain states. Even more importantly, it will make the diagnosis of chronic posttraumatic or postsurgical pain statistically visible and, it is hoped, stimulate research into these pain syndromes.

We investigated whether intraoperative 'subanesthetic doses' of ketamine have a postoperative anti-hyperalgesic and an analgesic effect and which is the preferential route of administration, either systemic (intravenous, i.v.) or epidural. One hundred patients scheduled for rectal adenocarcinoma surgery under combined epidural/general anesthesia were included. Before skin incision all the patients received an epidural bolus followed by an infusion of continuous bupivacaine/sufentanil/clonidine mixture. They were randomly assigned to receive no ketamine (group 1), i.v. ketamine at the bolus dose of 0.25 mg/kg followed by an infusion of 0.125 mg/kg per h (group 2), 0.5 mg/kg and 0.25 mg/kg per h (group 3), epidural ketamine 0.25 mg/kg and 0.125 mg/kg per h (group 4), or 0.5 mg/kg and 0.25 mg/kg per h (group 5). All i.v. and epidural analgesics were stopped at the end of surgery and patients were connected to an i.v. morphine patient-controlled analgesia (PCA) device. Short-term postoperative analgesia (72 h) was assessed by pain visual analog scale scores at rest, cough, and movements as well as by PCA requirements. Wound mechanical hyperalgesia was evaluated and residual pain was assessed by asking the patients at 2 weeks, and 1, 6, and 12 months. The area of hyperalgesia and morphine PCA requirements were significantly reduced in group 3. These patients reported significantly less residual pain until the sixth postoperative month. These observations support the theory that subanesthetic doses of i.v. ketamine (0.5 mg/kg bolus followed by 0.25 mg/kg per h) given during anesthesia reduce wound hyperalgesia and are a useful adjuvant in perioperative balanced analgesia. Moreover, they show that the systemic route clearly is the preferential route.

Summary Effective peri‐operative pain management is a prerequisite for optimal recovery after surgery. Despite published evidence‐based guidelines from several professional groups, postoperative pain management remains inadequate. The procedure‐specific pain management (PROSPECT) collaboration consists of anaesthetists and surgeons with broad international representation that provide healthcare professionals with practical and evidence‐based recommendations formulated in a way that facilitates clinical decision‐making across all stages of the peri‐operative period on a procedure‐specific basis. The aim of this manuscript is to provide a detailed description of the current PROSPECT methodology with the intention of providing the rigour and transparency in which procedure‐specific pain management recommendations are developed. The high methodological standards of the recommendations should improve the quality of clinical practice.

Combined with an antihyperalgesic dose of ketamine, intraoperative epidural analgesia provides effective preventive analgesia after major digestive surgery.