Spinal Analgesia

Spinal analgesics

The important issues to be emphasized when considering the intrathecal administration of novel analgesics are their proven antinociceptive effect, safety (short- and long-term effects on the spinal cord and potential toxicities), stability in shelf solution and at body temperature by itself, or in combination with other drugs in spinal fluid, compatibility with a long-term spinal infusion pump, whether they are of sufficiently high potency and solubility to be used in the finite volume of an implanted infusion pump, and if a pharmaceutical company is willing to invest the immense resources needed for US Food and Drug Administration approval and subsequent commercial development.

Epidural and spinal agents for postoperative analgesia

The discovery of opioid receptors and the subsequent development of the technique of epidural and intrathecal opioid administration are undoubtedly two of the most significant advances in pain management in recent decades. The use of spinal opioids is widespread and increasing. The technique is used widely to treat intraoperative, postoperative, traumatic, obstetric, chronic, and cancer pain. Newer developments include the increasing use of combined local anesthetics and opioids or nonopioids and also PCEA, particularly in the obstetric population. Meta-analysis of controlled trials has demonstrated improved pulmonary outcome in patients receiving epidural postoperative analgesia. Although rare, respiratory depression continues to be a major problem of the technique. None of the currently available opioids is completely safe; however, extensive international experience has shown that patients receiving spinal opioids for postoperative analgesia can be safely nursed on regular wards, provided that trained personnel and appropriate guidelines are available. The importance of a good acute pain service to provide the safe and effective use of spinal opioids cannot be overemphasized.

Complications related to thoracic epidural analgesia: a prospective study in 1071 surgical patients

In a prospective study, the complications of 1071 patients scheduled for thoracic epidural catheterization for postoperative analgesia (TEA) were studied. All catheters were inserted preoperatively between segment Th 2/3 and Th 11/12 under local anesthesia. Balanced anesthesia with endotracheal intubation and TEA were combined. Postoperatively 389 patients (36.9%) were monitored on a normal surgical ward. Buprenorphine, 0.15 to 0.3 mg, and if needed bupivacaine 0.375% 3-5 ml h-1 were given epidurally. Primary perforation of the dura occurred in 13 patients (1.23%). Radicular pain syndromes were observed in six patients (0.56%). In one patient (0.09%) respiratory depression was seen in close connection with the epidural administration of 0.3 mg buprenorphine. Although 116 patients (10.83%) showed one abnormal clotting parameter but no clinical signs of hemorrhage, there was no complication related to this group. No persisting neurological sequelae caused by the thoracic epidural catheters were found. In conclusion, continuous TEA with buprenorphine for postoperative pain relief after major abdominal surgery is a safe method without too high a risk of catheter-related or drug-induced complications, even on a normal surgical ward and when one clotting parameter is abnormal.

Epidural infusion of bupivacaine and diamorphine for postoperative analgesia. Use on general surgical wards

An audit of postoperative epidural analgesia in a District General Hospital is presented. Three hundred and forty-eight patients received epidural infusions of a bupivacaine and diamorphine mixture, and were managed on general surgical wards using a standard protocol of observations and instructions. Good analgesia was achieved in 339 (97%) patients. Respiratory depression, defined as a respiratory rate of eight breaths.min-1 or less, occurred in 22 (6%) patients, was of gradual onset, and was simply and successfully managed without morbidity. There were no respiratory arrests. Other complications, and the significance of catheter insertion level are discussed.

Spinal opioids: a nursing perspective

Nursing care of the patient receiving spinal opioids for pain control is reviewed in a comprehensive manner. Selection of patients, nursing management and patient outcomes are discussed. Three pain control techniques are described: epidural opioid injection for cancer pain, epidural opioid infusion for acute postoperative pain, and single dose spinal opioids for postcesarean section pain. Monitoring and pharmacologic aspects common to all three forms of spinal opioid treatment are given, and specific nursing interventions for each therapy are delineated.

Management of postoperative pain: review of current techniques and methods

Pain is a common problem in the early postoperative period. Techniques that provide perioperative analgesia to alleviate pain may have a significant effect on postoperative events, such as earlier ambulation and earlier dismissal from the hospital with use of epidural analgesia than with systemic analgesia. Spinal opioids, which can be administered epidurally or intrathecally, provide analgesia that is superior to that achieved with systemically administered narcotics. For procedures on the upper extremities, selective analgesia can be achieved with use of various types of neural blockade--for example, brachial plexus blockade, interscalene blockade, and axillary plexus blockade. Intercostal nerve block, a valuable but underutilized procedure appropriate for unilateral upper abdominal or flank operations or for thoracotomy, has been shown to reduce postoperative narcotic requirements and pulmonary complications. A patient-controlled analgesia device, consisting of an electronically controlled infusion pump with a timing device that can be triggered by the patient for intravenous administration of a narcotic when pain is experienced, avoids the vast fluctuations in analgesia that accompany parenteral administration of drugs. In most patients, postoperative pain can be prevented or diminished, and clinicians should be aware of the available techniques for achieving this goal.