Risk factors of inadequate pain relief during epidural analgesia for labour and delivery.

PURPOSE: To determine the causes of failure of epidural analgesia during labour and delivery. METHODS: During six months, pregnant patients receiving epidural analgesia and delivering vaginally were studied prospectively. Bupivacaine 0.125% was used for the initial bolus dose and subsequent continuous infusion. Top-ups of the same solution were used for inadequate pain relief assessed using a visual analogue pain score (VAPS) and/or by clinical examination. Inadequate pain relief was defined as the need for > or = 2 top-ups in addition to epidural infusion and failure during delivery as VAPS > or = 30 mm during the expulsion phase. RESULTS: 1009 patients delivered during this period, 596 had epidural analgesia for vaginal delivery of a live infant and data were complete in 456. Inadequate pain relief during labour and during delivery were found in 5.3% and 19.7% of patients. Risk factors of inadequate pain relief included: inadequate analgesic efficacy of the first dose (Odds ratio: 3.5, P = 0.001) and posterior presentation (Odds ratio: 5.6, P = 0.001). Radicular pain during epidural placement was associated with failure during labour (Odds ratio: 3.9, P = 0.05). Duration of epidural analgesia > six hours (Odds ratio: 9.1, P = 0.001) was a risk factor for insufficient pain relief during labour whereas duration of epidural analgesia < one hour was associated with pain during delivery (Odds ratio: 18.3, P = 0.001). CONCLUSION: Several obstetrical and epidural-related factors increase the risk of inadequate epidural analgesia. For some, simple changes of practice pattern may lead to improved pain relief.

The plasticity of cutaneous hyperalgesia during sympathetic ganglion blockade in patients with neuropathic pain.

In order to investigate the plasticity of cutaneous sensory abnormalities in neuropathic pain, we monitored sensory and vasomotor effects of diagnostic sympathetic ganglion blocks in 24 patients, who suffered from chronic pain and cutaneous hyperalgesia following peripheral nerve or tissue injury. Ongoing pain was rated on a visual analogue scale, and pain evoked by innocuous tactile and cooling stimuli (hyperalgesia) on a verbal rating scale. Skin temperatures were determined at symmetric sites. In two patients, cutaneous blood flow was measured with a laser Doppler device. The sympathetic blocks led to a significant reduction of the group mean ongoing pain (40%) and cutaneous hyperalgesia (50%). Between patients, however, there was a large variability that could not be related merely to adequacy of sympathetic blockade. Neither the magnitude of change in skin temperature nor the final skin temperature after the block correlated with the amount of pain relief. The relief of hyperalgesia, however, correlated with the relief of ongoing pain. Nine patients experienced pain relief of greater than 50%. In these patients, the time course of hyperalgesia relief was similar to the time course of relief of ongoing pain. pain relief occurred simultaneously with or a few minutes before cutaneous vasodilatation. During the block, even vigorous mechanical or cold stimuli did not rekindle hyperalgesia. In all patients, pain and hyperalgesia returned within a day after the block. In three patients tested, passive warming of the limb to the temperature achieved by the sympathetic block had negligible effects on pain and hyperalgesia. The hyperalgesia of sympathetically maintained pain is thought to be due to sensitization of central pain-signalling neurons to mechanoreceptor input. The present data indicate that this sensitization is highly plastic even when the disease has persisted for months or years. It could be reversed within minutes by a sympathetic blockade, but returned when sympathetic block subsided. Mechanoreceptor input by itself was not sufficient to maintain or rekindle the central sensitization. This supports the hypothesis that low-grade activity of nociceptors, possibly due to development of alpha-adrenergic sensitivity after injury, is involved in the maintenance of central sensitization.

Fetal oxygen saturation during epidural and paracervical analgesia.

BACKGROUND: We wanted to assess changes in fetal oxygenation during maternal epidural or paracervical analgesia in labor. METHODS: A prospective, open and non-randomized study. Twenty healthy parturients were enrolled before they asked for pain relief. Informed consent was obtained. Fetal and maternal oxygen saturations were measured before and up to 1 h after the initiation of analgesia. Fetal oximetry was performed with the Nellcor N-400 oximeter+FS-14B fetal oxygen sensor (Nellcor Puritan Bennett, Pleasanton, California, USA). Maternal oximetry was done with Datex Satlite portable monitor (Datex, Finland). Visual analog scale was used for assessing pain relief. Two-way analysis of variance and students t-test were used for statistical analyses. RESULTS: Fetal oxygenation initially improved in both groups. The saturation then returned to baseline in both groups. In the epidural group, the values remained at baseline or slightly below, while in the paracervical group the saturation remained a little higher than baseline (p=0.009). No change was seen in maternal oxygenation or heart rate. No change in fetal heart rate was found either. Epidural block was superior to paracervical block with respect to pain relief (p=0.002). CONCLUSIONS: There was a small but significant difference in fetal oxygenation between epidural and paracervical groups during the observation period. The magnitude of the difference is hardly clinically significant. A larger, randomized study is needed to elucidate the mechanisms behind this finding.

Postoperative pain therapy: a survey of patient attitudes to postoperative pain relief

We surveyed the attitudes of general surgical patients to the management of their postoperative pain relief. Elective surgical patients (n = 232) were asked postoperatively about their experienced pain which was expressed according to verbal pain scale, the duration of experienced pain, satisfaction with pain relief and medication, and expectations of pain on the 5th to 7th postoperative day. Thirteen percent of the patients had no pain, 47% of whom had no rest pain but pain on moving or coughing, 32% of whom had rest and moving pain, and 0.4% of whom experienced horrible and excruciating pain. Duration of postoperative pain was 2.5 +/- 1.9 days, and 76% of the patients experienced pain only for 3 postoperative days. Results of the interviews indicated that 80% of these patients were satisfied with their postoperative pain relief. Although 80% expressed satisfaction, 39% of whom did have rest pain. In the patients with continuous epidural infusion of buprenorphine and 0.25% bupivacaine, incidence of complained rest pain was significantly low compared with those with intermittent i.v. and/or im injection of analgesics on demands of patients. Lag between patient's demand and nurse's response concerning medication correlated significantly to the satisfaction. There was no relation between satisfaction and age, the nature of operation or sex. Fifty-two percent of the patients reported that degree of experienced pain had been less than expected preoperatively. In conclusion, 80% of the patients were satisfied, but our postoperative pain therapy was still insufficient because 39% of them had rest pain.(ABSTRACT TRUNCATED AT 250 WORDS)

Non-oncologic chronic pain relief with opioids

Opioids for non cancer pain control are controversial. The evaluation of the pain relief, changes in quality of life and complications due to long term infusion of opioids in the lumbar subarachnoid space in 11 patients with non cancer pain were the goals of this study. Patients were previously treated with drugs and surgical procedures, without significant pain relief. Patients were asked to compare pain characteristics and daily life activities before and after this treatment. The long term spinal opioids through implantable pumps for non-oncologic pain produced pain relief but did not improve the quality of life in the majority of the cases.

Efficacy of epidural neurolysis

Forty-one patients were treated with epidural neurolysis using 50 % ethyl alcohol 2 ml. Thirty eight patients were suffering from cancer pain and three patients were complaining of chronic benign pain. Alcohol block was repeated 2.3 times (mean) in the same patient. Thirty patients were followed after the treatment. Forty-seven percent of the patients reported 70 % or greater pain relief and 20 % of the patients reported about 50 % pain relief. Duration of pain relief was from 9 days to 203 days with a mean duration of 54 days. Adverse effects were reported 43 % of the patients. There is no miserable adverse effect. Adverse effect reported most was pain with epidural injection of drugs after the alcohol block had been performed.

Vestibular schwannoma surgery and headache.

The aim of the study was to evaluate aetiological factors for postoperative headache after vestibular schwannoma (VS) surgery with respect to asymmetric activation of vestibular reflexes. After surgery, 27 VS patients with persistent postoperative headache, 16 VS patients without headache and 9 healthy controls were examined. The vestibular, cervicocollic and cervicospinal reflexes were evaluated to study whether asymmetric activation of vestibular reflexes could cause headache. The effect of neck muscle and occipital nerve anaesthesia and the effect of Sumatriptan ( Imitrex ) on headache were also evaluated. The vestibular function of VS patients with headache did not differ from that of VS patients without headache, but was abnormal when compared to that of normal controls. The cervicospinal and cervicocollic reflexes did not differ in the patient groups. Injection of lidocaine around the operation scar gave pain relief to two patients, and one of them had occipital nerve entrapment. Infiltration of lidocaine deep in the neck muscles in the vicinity of the C2 root did not alleviate headache, but caused vertigo. Nine patients with musculogenic headache got pain relief from supportive neck collars, and two patients with cervicobrachial syndrome got pain relief from manual neck traction. The study shows that asymmetric activation of cervicocollic reflexes does not seem to be the reason for headache. Headache seems to be linked to neuropathic pain, allegedly caused by trigeminal irritation of the inner ear and the posterior fossa, which has recently been linked to vascular pain.

Response of intractable pain to continuous intrathecal morphine: a retrospective study.

We have treated 37 patients with intractable pain (35 with cancer-related pain) by continuous intrathecal morphine infusion via implanted pump. These patients were carefully selected according to specific criteria, and each demonstrated a significant reduction in pain following a test dose of intrathecal morphine. All patients had good pain relief from intrathecal morphine infusion, even with pain located in cervical dermatomes. Systemic narcotics could be withdrawn from most patients. Significant side effects were rare and typically self-limited. Many patients required gradually increasing doses, seemingly related to disease progression. Two patients with non-malignant pain have had variable dose requirements over 28 and 44 months without clear tolerance. In these patients we observed a reduction in side effects associated with systemic opioids when continuous intrathecal opioid infusion was instituted. Intrathecal opioid administration may have fewer complications than ablative pain relief procedures. In properly selected patients, this method offers an effective alternative for pain relief.

Celiac plexus block: injectate spread and pain relief in patients with regional anatomic distortions.

BACKGROUND: The success of the neurolytic celiac plexus block, despite different approaches and methods used, depends on adequate spread of the injectate in the celiac area. This retrospective study was conducted to evaluate the patterns of alcohol spread and pain relief in patients with cancer or therapy-related anatomic distortion of the celiac area. METHODS: From 177 cancer patients who underwent computed tomography (CT)-guided single-needle neurolytic celiac plexus block via an anterior approach, a radiologist, blind to the aim of the study, retrospectively selected 105 patients with abnormal anatomy of the celiac area as judged by CT images obtained before the block. To evaluate CT patterns of neurolytic (mixed with contrast) spread, the celiac area was divided on the frontal plane into four quadrants: upper right and left and lower right and left, as related to the celiac artery. Results were expressed as the number of quadrants into which contrast spread, ie., four, three, two, or one quadrants with contrast. The patterns of contrast spread according to the number of quadrants with anatomic distortion were analyzed. Patient assessment by visual analog scale was reviewed to evaluate the degree of pain relief. pain relief 30 days after block was considered long-lasting. pain relief at 30 days after block was analyzed according to the number of quadrants with contrast. RESULTS: Overall, four, three, two, and one quadrants with contrast were observed in 9 (8%), 21 (20%), 49 (47%), and 26 (25%) patients, respectively. An inverse correlation was observed between the number of quadrants with anatomic distortion and the number of quadrants with contrast (P < 0.001). Long-lasting pain relief was noticed in nine of nine patients (100%; 95% confidence interval, 66-100) with contrast in four-quadrants, and in 10 of 21 patients (48%; 95% confidence interval, 26-70) with contrast in 3 quadrants (P < 0.01). None of the 75 patients with contrast in two quadrants or one quadrant experienced long-lasting pain relief. CONCLUSIONS: These findings suggest that, using the single-needle anterior approach, the neurolytic spread in the celiac area is highly hampered by the regional anatomic alterations. It also appears that only a complete (four quadrants) neurolytic spread in the celiac area can guarantee long-lasting analgesia, and that this picture may be obtained in a very limited fraction of patients with regional anatomic alterations.

Bilateral thoracoscopic splanchnicectomy in patients with chronic pancreatitis.

BACKGROUND: Intractable pain, the most prominent feature of chronic pancreatitis, causes the patient great disability, and its treatment poses a difficult problem for gastroenterologist and surgeon alike. The main goal of treatment is to provide sufficient and lasting pain relief without the use of opiates. Conservative management, including stopping alcohol consumption, dietary measures, pancreatic enzyme suppletion and analgesics, is discussed. When these measures fail, surgery is often unavoidable. Indications, effect on pain relief, morbidity and mortality of drainage and resection procedures are described. Bilateral thoracoscopic splanchnicectomy, a newly developed operation to alleviate pain irrespective of the type of anatomic abnormality, is outlined in more detail. Early encouraging results of pain relief in patients with chronic pancreatitis after thoracoscopic splanchnicectomy are presented.