Friday, July 15, 2011

Postsurgical Pain Undertreated in Most Patients

Acute Pain Even with all of the advances in medical science, patients in America only have a 1 in 4 chance of receiving adequate pain relief following surgery. It is even worse in many other parts of the world, according to recent commentary in The Lancet medical journal, and this unresolved acute postoperative pain often leads to problematic chronic pain conditions, affecting up to half of patients undergoing common operations.

A prior Pain-Topics UPDATE [here] discussed another article in The Lancet series on pain, which focused on the epidemic of unresolved chronic noncancer pain worldwide. In this second paper, Christopher L Wu and Srinivasa Raja from John Hopkins University School of Medicine, Baltimore, review the progress made in treatments for postoperative pain over the past decade [Wu and Raja 2011] They stress that, despite considerable advancements in pain management, a high percentage of patients continue to experience moderate-to-severe pain after surgery. And, inadequate post-surgical pain management is not just limited to adults; a study from the U.S. reported as many as 86% of children experiencing significant pain on the first day home after undergoing routine procedures like tonsillectomy.

Recent research also shows that the development of chronic pain after surgery, known as persistent postsurgical pain, or PPP, is a frequent outcome. From 30% to 50% of patients undergoing common operations such as mastectomy, thoracotomy, hernia repair, and coronary artery bypass become afflicted with PPP. They authors say: “Why there has been little progress in the treatment of acute postoperative pain is unclear, but the causes might be multifactorial, including the continued paucity of pain assessment and documentation, heightened awareness and increased number of audits or surveys leading to increased identification of undertreatment of pain… deficiencies in educational pain management programs for healthcare workers, underuse of effective analgesic techniques, and poor adherence to available guidelines.”

However, some interventional techniques have had a substantial impact on pain control during the past decade. In particular, regional analgesic techniques (such as epidural analgesia and peripheral nerve catheters using local anesthetics) have been associated with lower pain scores, earlier mobility, and reduced length of hospitalization compared with the use of systemic opioids. Although, there is some evidence that opioids are not always being used most advantageously or adequately. Other promising interventions still under development include a transdermal iontophoretic patch for the patient-controlled delivery of pain medication providing a needle-free effective alternative to the intravenous pump; extended-release local anesthetics; and disposable devices allowing infusion of local anesthetics on an outpatient basis.

The authors conclude: “Additional studies on predictors of postoperative pain and persistent postsurgical pain, efficacy of multimodal analgesic regimens (using more than one class of pain medication or technique), and growth of promising new technologies might lead to substantial gains in the treatment of acute postoperative pain and a potential reduction in the development of persistent pain states.”

COMMENTARY: The recently released report from the U.S. Institute of Medicine (IOM) — “Relieving Pain in American” [see UPDATE here] — devotes considerable attention to the problem of acute pain. While observing that an astounding 116 million persons in the U.S. suffer chronic pain, the authors note that the risk of both acute and chronic pain is affected by many factors, including age, race, sex, income, education, urban/rural living, and other demographic factors. The likelihood of experiencing a transition from acute to chronic pain is likewise influenced by various factors, especially the adequacy of acute pain relief.

Despite some studies to the contrary, hospitals and extended care facilities in the U.S. often appear to receive acceptable grades for managing acute pain. Although, the IOM authors note that 60% of persons visiting hospital emergency departments have acute painful conditions — including 2.1 million visits per year for acute headache alone — and 74% of those persons are discharged in moderate to severe pain.

Among the consequences of severe acute pain, aside from the hurt itself, is reduced mobility and consequent loss of strength, impaired physical function, disturbed sleep, reduced quality of life, immune impairment and increased susceptibility to disease, dependence on medication, codependence with solicitous family members and other caregivers, and increased risks of developing chronic pain. The IOM panel recommends that preventing pain (for example, acute pain following surgery or dental procedures) and averting the transition from acute to chronic pain should be top clinical priorities.

REFERENCE: Wu CL, Raja SN. Treatment of acute postoperative pain. The Lancet. 2011(Jun);377(9784):2215-2225 [abstract here].