Invasive analgesia techniques for advanced cancer pain.

Because most cancer pain involves multiple anatomic sites, invasive techniques are intended to be analgesic adjuvants and not serve as the definitive treatment. These procedures often allow patients to reduce their dosages in their current drug regimens or to derive greater pain relief from their present doses in order to improve their quality of life. Medical care of the suffering pain patient requires a multimodality, multispecialty approach combining psychotherapy, social support, and pain management to provide the best possible quality of life or quality of dying.

The effects of volatile anesthetic agents on pulmonary surfactant function.

The purpose of this article is to review the findings from research directed at understanding the effects of volatile anesthetics on the respiratory surface known as pulmonary surfactant. Anesthetics have long been known to have a disruptive effect on biological membranes. This review will highlight the interactions of volatile anesthetics with pulmonary surfactant. This paper has emphasized the interaction of volatile anesthetics with the pulmonary surfactant monolayer versus the lipid bilayer. The goal of this review is to uncover to what extent this understanding has progressed in forty years. Although the goal is quite broad, the information gathered and the advice given is specific. Theories of anesthesia and surfactant structure and function are summarized and discussed in light of early physico-chemical approaches and extend to an era where powerful new three-dimensional structural techniques can be used to answer this question.

NCCN Practice Guidelines for Cancer Pain.

The overall approach to pain management encompassed in these guidelines is comprehensive. It is based on objective pain assessments, utilizes both pharmacologic and nonpharmacologic interventions, and requires continual reevaluation of the patient. The NCCN Cancer Pain Practice Guidelines Panel believes that cancer pain can be well controlled in the vast majority of patients if the algorithms presented are systematically applied, carefully monitored, and tailored to the needs of the individual patient.

Evaluation of peripheral morphine analgesia for lumpectomy and axillary node dissection: a randomized, double-blind, placebo-controlled study.

BACKGROUND AND OBJECTIVES: Morphine may elicit potent antinociceptive effects by binding and activating peripheral opioid receptors. However, the results in clinical studies have varied. We examined the postoperative analgesic effects of incisional morphine in patients undergoing lumpectomies and axillary node dissections for breast cancer. For this purpose, a concentration of morphine within the range (0.25-0.6%) of those utilized in previous studies for postarthroscopy analgesia was chosen (0.6%). METHODS: Forty-five patients scheduled to undergo a lumpectomy and axillary node dissections for breast cancer were enrolled in this study after receiving Ethics Committee approval and patient consent. Patients were randomized to undergo irrigation of the surgical sites for 5 minutes prior to skin closure with 6 mg morphine diluted in 100 mL 0.9% normal saline (NS) and placebo intramuscular (i.m.) (peripheral MS group), 100 mL of 0.9% NS alone and placebo i.m. (placebo group), or 100 mL of 0.9% NS and 6 mg morphine i.m. in the deltoid muscle (i.m. MS group) in a double-blind fashion. In the postanesthesia care unit, patients received fentanyl via a patient-controlled analgesia (PCA) device programmed to deliver 25 microg every 10 minutes to a maximum dose of 150 microg/h. Patients were evaluated for pain using a visual analog scale card from 0-10, opioid consumption, and incidences of side effects at 2, 6, 12, 18, and 24 hours after surgery. RESULTS: All patients had adequate analgesia at rest and during arm movement with visual analog pain scores (VAPS) <3/10 throughout the study period. There were no significant differences in demographics, total fentanyl consumption (500 vs. 475 vs 933 microg, respectively; P = .2), VAPS at rest and during arm movement as well as fentanyl consumption at the different evaluation points among the three groups. CONCLUSIONS: These results suggest that under the conditions of the study protocol, there is no value in utilizing morphine in solution at the surgical site for postoperative lumpectomy and axillary node dissection analgesia.

Acute herpetic neuralgia and postherpetic neuralgia in the head and neck: response to gabapentin in five cases.

BACKGROUND AND OBJECTIVES: The clinical presentations and pharmacologic management of three patients with acute herpetic neuralgia (AHN) and two patients with postherpetic neuralgia (PHN), confined to the head and neck region, are described. METHODS: Two patients had pain in the ophthalmic division of the trigeminal nerve, two had pain confined to the C2-C4 dermatomes, and one patient had C2 pain with radiating and referred pain to the second and third divisions of the trigeminal nerve. RESULTS: Gabapentin, an anticonvulsant drug, was effective in treating these patients, including the two cases of AHN. All patients reported complete pain relief after titration with gabapentin up to 1,800 mg/d. The patients noted a dose-dependent decrease in pain almost immediately after starting gabapentin. Specifically, reduction in the frequency and intensity of allodynia, burning pain, shooting pain, and throbbing pain were noted. None of the patients experienced side effects from the drug. CONCLUSIONS: In view of the results in these patients, blinded, controlled studies are needed to determine the efficacy of gabapentin for treating AHN and PHN.

The relationship between depression and pain language in cancer and chronic non-cancer pain patients.

The present study investigated the relationship between depression and pain description among cancer and chronic non-cancer pain patients in a large outpatient sample. Participants consisted of 312 patients (158 men and 154 women) attending a pain management clinic at a comprehensive cancer institute. Sixty-one percent of the patients (190/312) were experiencing pain related to cancer and 39% (122/312) were experiencing chronic nonmalignant pain. Multivariate analyses of covariance were used to assess differences in the sensory and affective indices of the McGill Pain Questionnaire (MPQ) associated with depression and type of pain. Current pain intensity was the covariate. The results indicated that the MPQ affective and sensory intensity scales did not significantly differ among patients with cancer and chronic non-cancer pain. There were also no significant differences in the percentage of affective and sensory pain descriptors chosen by these patients. However, depression significantly influenced MPQ pain description. Depressed patients with pain scored higher on the affective pain intensity dimension of the MPQ than non-depressed patients with pain (P < 0.001). Depressed patients also chose more affective pain descriptors than non-depressed patients (P < 0.001). Chi-square analyses revealed that depressed and non-depressed pain patients made significantly different choices on four of the five MPQ affective adjective lists. There were no differences in the sensory pain index or the percentage of sensory pain descriptors based on depression. These findings are discussed in terms of their clinical implications and their relationship to the existing literature.

Asystole as a neurologic sign.

The authors present a case of asystole occurring during dural closure following craniotomy with the patient in the supine position. This 22-year-old woman had a left parietal lobe tumor resected with bipolar cautery. Standard intraoperative monitoring with a left radial arterial line and a right internal jugular central venous catheter was used during the surgery. The anesthetic course was complicated by intraoperative bleeding that responded to three units of fresh frozen plasma. Prior to closure, the operative site appeared dry and intact. After closure, asystole occurred suddenly and resolved with evacuation of 500 ml of blood. It is speculated that the asystole was preceded by an acute increase in intracranial pressure and a subsequent secondary brainstem compression.

Neurolytic superior hypogastric plexus block for chronic pelvic pain associated with cancer.

BACKGROUND AND OBJECTIVES: Neurolytic superior hypogastric plexus block has been shown to be safe and effective in selected cancer patients. A large cohort of patients was studied to evaluate the continued efficacy and safety of this block in cancer patients with advanced disease. METHODS: A total of 227 pelvic pain patients with gynecological, colorectal, or genitourinary cancer who experienced poor pain control due to either progression of disease or to untoward side effects were enrolled in this study during a 3-year period. All pain patients receiving oral opioids were eligible to participate. A bilateral percutaneous neurolytic superior hypogastric plexus block with 10% phenol was performed 1 day after a successful diagnostic block with 0.25% bupivacaine. RESULTS: All patients reported a visual analog scale (VAS) pain score of 7-10/10 before the block. A positive response to a diagnostic block was obtained in 159 patients (79%). Overall, 115 patients of the 159 patients who responded to a diagnostic block (72%, 95% confidence interval of 65-79%) had satisfactory pain relief (VAS < 4/10), 99 (62%) after one block, and 16 (10%) after a second block. The remaining 44 patients (28%) had moderate pain control (VAS 4-7/10) after two blocks and received oral pharmacological therapy and epidural analgesic therapy with good results. Both groups experienced significant reductions in oral opioid therapy after the neurolytic blocks. No additional blocks were required by patients who had a good response during a follow-up period of 3 months. No complications related to the block were detected. CONCLUSIONS: Neurolytic superior hypogastric plexus block provided both effective pain relief and a significant reduction in opioid usage (43%) in 72% of the patients who received a neurolytic block. Overall, this represents 51% of the patients enrolled in the study. Poor results should be expected in patients with extensive retroperitoneal disease overlying the plexus because of inadequate spread of the neurolytic agent.

Postoperative epidural opioid analgesia: what are the choices?

The administration of hydrophilic opioids via a continuous infusion results in selective spinal analgesia with a low incidence of side effects. Lipophilic opioids may also be associated with spinal effects. However, the doses required to produce postoperative analgesia also produce plasma concentrations within the MEAC. Thus, in clinical practice it may not be possible to limit epidural doses of lipophilic opioids to those associated with spinal analgesia. Regardless of the mechanism of action, epidural administration of lipophilic opioids may offer no clinical advantages over the IV route. Notwithstanding, epidural administration of small doses of lipophilic opioids in combination with local anesthetics may offer significant clinical advantages over systemic administration of opioids alone. Dose-ranging studies will be necessary to determine the ideal concentrations of opioids and local anesthetics, as well as the ratios of the two drugs to obtain optimal analgesia with minimal incidence of side effects.

Bowel function recovery after radical hysterectomies: thoracic epidural bupivacaine-morphine versus intravenous patient-controlled analgesia with morphine: a pilot study.

STUDY OBJECTIVE: To determine if the use of continuous epidural bupivacaine-morphine in the perioperative period is associated with a significant decrease in the recovery time of postoperative ileus when compared with parenteral morphine administration. DESIGN: Prospective (quality of analgesia) and retrospective (bowel function recovery), nonrandomized study. SETTING: Inpatient gynecology-oncology patients at a university-affiliated tertiary cancer center hospital. PATIENTS: 68 women who experienced uncomplicated radical hysterectomies for cancer. INTERVENTIONS: Intraoperative epidural-general anesthesia or general anesthesia only was administered. Postoperative continuous epidural analgesia with bupivacaine-morphine and intravenous (IV) morphine via patient-controlled analgesia (PCA). Both forms of therapy were titrated to provide patients with a dynamic visual analog pain score of 5 or less on a 10-point scale throughout the study period. Patients were weaned from infusions when pain scores remained at less than 5 for 12 hours and no breakthrough medication was used. MEASUREMENTS AND MAIN RESULTS: Rest and dynamic pain scores, time of first flatus, length of nasogastric therapy, time to solid food intake, daily and total morphine requirements and length of hospitalization were recorded. The epidural group required fewer days of nasogastric therapy (4 +/- 3 versus 8 +/- 2 days, p = 0,0001), tolerated solid foods sooner (6 +/- 2 versus 11 +/- 3 days, p < 0.0001), and had a shorter hospitalization time (10 +/- 3 versus 14 +/- 4 days, p = 0.0001) when compared with the PCA group. CONCLUSIONS: The use of thoracic epidural bupivacaine-morphine results in a decrease in the duration of postoperative ileus, which was associated with earlier hospital discharge.

The influence of preoperative concentrations of beta-endorphin and met-enkephalin on the duration of analgesia after transurethral resection of prostate.

beta-Endorphin (beta-EP) and methionine-enkephalin (M-EK) are endogenous peptides that play a role in the modification of pain perception and analgesia threshold. In order to understand more about pathophysiology of pain in association with neuroaxial blocks, we evaluated cerebrospinal fluid (CSF) concentrations of beta-EP and M-EK prior to spinal anesthesia (SA) in patients undergoing transurethral resection of prostate (TURP) to determine the correlation between preanesthesia concentrations and the duration of postoperative analgesia and opioid requirements. Twenty-five healthy patients undergoing TURP under SA were enrolled. beta-EP and M-EK were measured with a competitive radioimmunoassay. Mean preoperative beta-EP and M-EK concentrations were 153 +/- 44 and 38 +/- 5 pg/mL, respectively. Those with beta-EP concentrations > 153 pg/mL had significantly longer analgesia (P < 0.01), and lower utilization of morphine in the first postoperative day (P < 0.01). Moreover, patients with milder postoperative pain (visual analog scale score < 4/10) had significantly higher beta-EP concentrations (P < 0.01). A similar correlation was not found with M-EK values. These data suggest that preoperative CSF beta-EP, but not M-EK, concentrations correlate with the duration and quality of postoperative analgesia, as well as opioid requirements after spinal anesthesia.

Perforation and partial obstruction of an armored endotracheal tube.

Armored endotracheal tubes are often used during cases in which there is a risk of compromise of a polyvinylchloride tube with positioning of a patient's head. The authors describe a case in which partial airway obstruction and perforation of such a tube occurred as a result of biting by a patient. Ways to avoid this complication are discussed.

Postoperative myocardial ischemia: epidural versus intravenous patient-controlled analgesia. A pilot project.

BACKGROUND AND OBJECTIVES: Continuous postoperative epidural analgesia with bupivacaine (BUP) and morphine (MS) may be associated with a decreased incidence of postoperative myocardial ischemia (ISCH) and infarction (MI). This study evaluated the incidence of ISCH and MI in patients with two or more risk factors for coronary artery disease (CAD) who were admitted to the ICU after upper abdominal surgery for cancer. METHODS: During a 1-year period, 198 patients were studied for the incidence of ISCH and MI in a prospective, nonrandomized fashion. The epidural group (EPI, n = 110) received continuous epidural anesthesia by injection at the T7-9 interspaces with 0.5% BUP/0.013% MS and light general anesthesia followed by 0.1% BUP/0.01% MS epidural analgesia for 5-7 days. The general anesthesia group (GEN, n = 88) received a balanced technique followed by intravenous patient-controlled analgesia with 0.1% MS for 5-7 days. All patients had preoperative and postoperative 12 lead ECGs every 6 hours on the first 3 postoperative days. Patients with ECG changes consistent with myocardial ischemia had creatine kinase levels with isoenzymes drawn every 8 hours. RESULTS: There were no differences in age, sex, number of cardiac risk factors, number taking anti-anginal medication, preoperative heart rate (75 +/- 5 [EPI] vs. 73 +/- 4 [GEN]), and incidence of preoperative or intraoperative ischemia between the two groups. All patients had adequate analgesia. Postoperatively, patients in the EPI group had a lower incidence of tachycardia (15 [14%] vs. 58 [65%], P < .00001), ischemia (5 [5%] vs. 15 [17%], P < .004), and infarction (0 vs. 3 [20% of patients with ischemia]). All episodes of ischemia were silent and occurred more frequently during the first 36 hours postoperatively (14 episodes or 72%). Overall 60% of the ISCH episodes were associated with tachycardia (5/5 in the EPI group and 7/15 in the GEN group). There were no deaths in either group. CONCLUSIONS: These preliminary results suggest that epidural anesthesia and analgesia may decrease the incidence of postoperative tachycardia, ischemia, and possibly infarction in patients undergoing upper abdominal procedures.

Epidural analgesia versus intravenous patient-controlled analgesia. Differences in the postoperative course of cancer patients.

BACKGROUND AND OBJECTIVES: This study evaluated 462 consecutive surgical cancer patients who underwent uncomplicated surgeries of the thorax or abdomen, or both, of more than 3 hours duration between 1989 and 1991. METHODS: Patients received either epidural analgesia (EA group) with 0.1% bupivacaine, 0.01% morphine sulfate after combined general-epidural anesthesia, or parenteral morphine therapy via intravenous patient-controlled analgesia (IV-PCA) after balanced general anesthesia after the operation. Patients in both the EA (n = 352) and IV-PCA (n = 100) groups were compared for demographics, length of surgical intensive care unit (SICU), and hospital stays. Moreover, the same comparisons were performed when patients were allocated into surgical subgroups: thoracic (TH), upper abdominal (UA), lower abdominal (LA), radical hysterectomies (RH), and RH with colon resection (RHCR). RESULTS: No differences existed with respect to age or sex between the EA and IV-PCA groups. All patients reported adequate dynamic pain control as evaluated with visual analog pain scores (VAS < 4/10), during the treatment periods (5 +/- 3 versus 5 +/- 2 days, EA versus IV-PCA). Overall, 262 (58%) patients were admitted to the SICU after the operation, 205 (58%) from the EA group and 57 (57%) from the IV-PCA group. Patients in the EA group required less ventilatory support than did those in the IV-PCA group (0.5 +/- 0.8 versus 1.2 +/- 0.9 days, P < .05). Patients in the EA group also spent less time in both the SICU (1.3 +/- 0.8 versus 2.8 +/- 0.6 days, P < .05) and in the hospital (11 +/- 3 versus 17 +/- 5 days, P < .05) than did their counterparts in the IV-PCA group. Significant differences were also found when subgroup comparisons were made. CONCLUSIONS: The use of both analgesic techniques was associated with satisfactory postoperative pain control. However, patients receiving epidural anesthesia and analgesia experienced faster recovery as judged by shorter mechanical ventilation time, and decreased SICU and hospital stays, resulting in significantly lower hospitalization costs. The use of perioperative epidural techniques should be considered to expedite recovery of surgical patients, and has the added benefit of being cost effective by reducing hospital stays.

Postoperative epidural bupivacaine-morphine therapy. Experience with 4,227 surgical cancer patients.

BACKGROUND: We prospectively studied surgical cancer patients who received epidural bupivacaine-morphine to determine perioperative morphine use, side effects, and complications. METHODS: All study patients received general-epidural anesthesia followed by epidural analgesia with 0.05% or 0.1% bupivacaine and 0.01% morphine at a rate of 5-10 ml.h-1 to keep the dynamic pain score at less than 5 (of 10). Patients were evaluated daily for pain relief, side effects, catheter migration, accidental removal, hypotension, respiratory rate, mental status changes, nausea and vomiting, and pruritus. RESULTS: Over 4 yr, 4,227 patients (61% women, aged 68 +/- 24 yr) were studied. Lumbar epidural catheters (n = 2,248 or 53.18%) were used more frequently than thoracic catheters (n = 1,979 or 46.82%) (P < 0.00001). Most of the patients were discharged to the surgical wards after the procedures (n = 3,001, 71%). Those patients (n = 1,226, 29%) admitted to the surgical intensive care unit, spent 1.2 +/- 0.8 days. Epidural catheter failure occurred in 283 (6.3%) patients. Length of epidural analgesia therapy was 6.3 +/- 2.6 days. There were three cases (0.07%) of respiratory depression which were treated with oxygen, intravenous naloxone, and by stopping the epidural infusion for 6 h. Hypotension occurred in 126 patients (3%). There were no apparent cases of catheter migration to either the subdural or subarachnoid space. Nausea or vomiting occurred in 929 patients (22%). Pruritus occurred in 930 patients (22%). CONCLUSIONS: Continuous epidural analgesia with 0.05-0.1% bupivacaine and 0.01% morphine is an effective method of postoperative analgesia with a low incidence of side effects, that can be safely administered on the surgical wards with no special monitoring equipment.