Respiratory depression following administration of intrathecal bupivacaine to an opioid-dependent patient

OBJECTIVE: To document two cases of respiratory depression in patients receiving morphine once the stimulating effect of pain on respiration was removed by bupivacaine. CASE SUMMARIES: Case 1: A 72-year-old 84-kg white man with cancer of the bladder and bone metastases had intense back and leg pain that was treated with intrathecal morphine for 6 months at an increasing dosage up to 10 mg twice daily. The intrathecal route was avoided for 4 days because of a suspected local infection at the site of the intrathecal catheter. During this 4-day period the patient received extended-release morphine and subcutaneous morphine daily. When the intrathecal route was used again, he received an identical dose of morphine plus bupivacaine and epinephrine. Ten minutes after the injection, fatal respiratory distress occurred. Case 2: A 92-year-old white woman was admitted for revascularization of arteritis on her left leg. To treat a painful sacrum and heel bedsores, she received extended-release oral morphine for 8 days. Induction of the intrathecal anesthesia was performed with bupivacaine. After 10 minutes, the patient became subcomatose, with miosis and apnea. Intravenous naloxone restored spontaneous respiration and normal consciousness. CONCLUSIONS: Pain is a physiologic antagonist of the respiratory depressant effects of opioid analgesics. By reducing pain stimulation, bupivacaine may make patients more susceptible to opioid respiratory depression. Such situations require titration of bupivacaine and other analgesics as well as increased monitoring of the patient.     

Maternal respiratory arrests, severe hypotension, and fetal distress after administration of intrathecal, sufentanil, and bupivacaine after intravenous fentanyl

The transjugular intrahepatic portosystemic shunt procedure is an effective intervention for patients with bleeding esophageal varices. Potential complications are numerous but rarely serious. A case of hemopericardium, cardiac tamponade, and death caused by perforation of the right atrium and aorta by a stent after embolization from the liver during stent placement is reported.     

Comparison of pre- versus post-incision administration of intrathecal bupivacaine and intrathecal morphine in a rat model of postoperative pain

BACKGROUND: Preclinical studies in experimental animals suggest that preemptive analgesia may improve postoperative pain management. The beneficial effects of preemptive analgesia appear less remarkable clinically. The purpose of this study is to examine the effect of pre- and post-incision administration of intrathecal bupivacaine and intrathecal morphine in a rat model for postoperative pain. METHODS: Rats with intrathecal catheters were anesthetized with halothane, and the surgical field was prepared. A saline vehicle or the test drug was administered 15 min before an incision was made in the plantar aspect of the hindpaw or after the incision was completed. After recovery, mechanical hyperalgesia to punctate and nonpunctate stimuli was measured. Rats were tested on the day of surgery for the first 5 h and each day for 6 days. RESULTS: In saline vehicle-treated rats, the median withdrawal threshold decreased from 522 mN to 54 mN or less, and the response frequency to pressure from application of the plastic disc increased from 0 +/- 0% to 96 +/- 12% or greater after incision. Hyperalgesia was persistent through 2 days after surgery and then gradually returned toward preincision values over the next 4 days. Pre- or postincision administration of either intrathecal morphine or intrathecal bupivacaine reduced hyperalgesia on the day of surgery; at all subsequent times, there were no differences between the saline vehicle groups and the drug treatment groups. There were never any significant differences between pre- and postincision treatments. CONCLUSIONS: Early reduction in pain behaviors either by pre- or postincision management had no impact on subsequent measures of hyperalgesia in this model. These results agree with a number of clinical studies and suggest that incisional pain may be initiated and maintained differently than pain in other models.     

Intrathecal sufentanil compared with epidural bupivacaine analgesia in labour

Epidural analgesia for pain relief during labour has certain disadvantages including slow onset. However, intrathecal sufentanil provides rapid onset and well-controlled analgesia lasting 1-4 h. The aim of this study was to compare the analgesia and the side effects of intrathecal sufentanil with epidural bupivacaine during labour. In a randomized, double-blind and controlled trial 58 parturient women requesting analgesia during labour were studied. The patients received either intrathecal sufentanil 10 micrograms and epidural saline, or intrathecal saline and epidural bupivacaine 20 mg. Visual analogue scores (VAS) for pain, blood pressure, heart rate, respiratory rate, level of sedation and the incidence of pruritus and nausea were recorded. Pain scores were significantly lower between 5 and 90 min after injection in patients receiving intrathecal sufentanil. Pruritus was significantly more frequent among those receiving intrathecal sufentanil. The rapid onset and effective analgesia of intrathecal sufentanil may in certain situations be advantageous.     

Epidural and intrathecal n-butyl-p-aminobenzoate solution in the rat. Comparison with bupivacaine

Lipoprotein(a) [Lp(a)] has been proposed as a restenosis risk factor, but it is not known if Lp(a) is present in the injured arterial wall during the initial neointimal growth. The purpose of this study was to determine if Lp(a) is incorporated into the vessel wall during rapid neointimal formation after arterial injury in primates. In this model, distention of the iliac artery with an angioplasty catheter caused focal breaks in the internal elastic lamina (IEL) in 80% of the vessels and extensive IEL fragmentation with medial disruption in 20% of the vessels. Neointimal growth was noted in all injured arteries; thrombus formation was noted in 40% of the vessels. Based on morphometric measurements, injured arteries had neointimal areas of 0.41 +/- 0.05 (n = 4) and 0.83 +/- 0.23 (n = 6) mm2 at 14 and 28 days after injury, respectively. Control arteries had an intact IEL and a monolayer of intimal cells. Lp(a) localization was examined histologically by using a mouse monoclonal anti-Lp(a) antibody. Lp(a), found in all injured arteries, was localized primarily in the neointima in 50% of the vessels. In the subset of vessels with evidence of thrombus formation, intense Lp(a) immunostaining was associated with the thrombus. Lp(a) was specific to injured arteries as uninjured vessels did not stain. In addition, staining was not seen with a negative control, a nonspecific mouse IgG1 antibody. The presence of Lp(a) at the site of rapid neointimal growth supports a role for this lipoprotein in the response to vascular injury after balloon angioplasty.     

Respiratory arrest following peribulbar anesthesia for cataract surgery: case report and review of the literature

Hypnic headache syndrome is a rare benign disorder which occurs in the elderly. It presents as a holocephalic or, less frequently, hemicranial headache during night sleep, lasting between 20 and 180 min; it is not associated with autonomic signs and responds well to lithium carbonate. We report a new case which responded well to indomethacin, and suggest that indomethacin may be used as an alternative treatment in this rare headache syndrome of the elderly.     

Analgesia following appendicectomy--the value of peritoneal bupivacaine

PURPOSE: Peritoneal inflammation is an important feature in many patients presenting with appendicitis. The contribution of peritoneal nerve fibres to pain experienced after appendicectomy has received little attention. METHOD: In this prospective double blind randomized study a consecutive series of 60 patients undergoing appendicectomy for suspected appendicitis were enrolled. A dose of 1.5 mg.kg-1 bupivacaine 0.5% was used. Group one patients received the entire dose of bupivacaine subcutaneously. Group two patients received half the dose subcutaneously (s.c.) and half the dose to the peritoneum. Pain scores were assessed pre-operatively and at 30 min, 12 and 24 hr post-operatively using a visual analogue scale. Time to first analgesia and total analgesia requirements in the first 24 hr were recorded. RESULTS: The patients receiving the s.c. combined with peritoneal bupivacaine had a lower pain score 30 min post-operatively (32 +/- 2 vs 54 +/- 4; P < 0.0001), a longer time to first analgesia (248 +/- 20 vs 164 +/- 17 min; P = 0.002) as well as lower opioid (68 +/- 5 vs 100 +/- 7 mg; P = 0.0002) and non steroidal analgesic requirements (65 +/- 6 vs 96 +/- 6 mg; P = 0.007) in the first 24 hr post-operatively. CONCLUSION: A combination of s.c. and peritoneal infiltration with bupivacaine is superior to skin infiltration alone in the relief of pain post appendicectomy.     

The effect of epidural injection of betamethasone or bupivacaine in a rat model of lumbar radiculopathy

STUDY DESIGN: The effect of epidural injection of betamethasone or bupivacaine was investigated in an animal model of lumbar radiculopathy. OBJECTIVE: To investigate the effects of an epidural steroid (betamethasone) or a local anesthetic (bupivacaine) in an animal model of radiculopathy produced by nerve root irritation. SUMMARY OF BACKGROUND DATA: Epidural injections are commonly used for the treatment of low back pain and sciatica. However, efficacy remains controversial, and there is a paucity of basic information to support clinical use or the injections. METHODS: Fifty-one rats were used. The left L4 and L5 nerve roots were loosely ligated with chromic gut, and either betamethasone, bupivacaine, betamethasone in combination with bupivacaine, or saline was injected using an epidurally placed catheter. The effects of epidural injection were evaluated using response to noxious stimuli and immunohistochemical methods. RESULTS: In betamethasone-treated rats (either alone or in combination with bupivacaine), thermal hyperalgesia was significantly less (P < 0.010 after surgery than that in saline- or bupivacaine-treated groups, in which the hyperalgesia was maximum at 2-3 postoperative weeks before resolving 5 weeks after surgery. Immunohistochemical analysis did not correlate with these results. CONCLUSIONS: Epidural steroid injection has a significant effect on the thermal hyperalgesia produced in a model of radiculopathy, which may provide clinical support for advocates of epidural steroids.     

Anaesthesia in a parturient with Noonan''s syndrome

During a randomized double-blind study to assess the antiviral activity of saquinavir (SQV) alone or in combination with zidovudine (ZDV), the emergence of phenotypic resistance was evaluated in 44 patients treated with SQV (13 subjects), ZDV (14 subjects), and SQV plus ZDV (17 subjects). A significant (P< 0.05) lower CD4+ cell count and higher HIV RNA copy number at entry were found in six patients who developed resistant viral strain (3 to ZDV and 3 to SQV) during the first 4 months of treatment. After 1 year, drug-resistant strains (12 to ZDV and 14 to SQV) were isolated in 26 out of 37 patients. A significant higher number of patients treated with ZDV alone (10/13) harbored ZDV-resistant strains compared to patients treated by combination therapy (2/13); whereas more than 50% of patients had SQV-resistant strains aside from treatment. Early SQV-resistant strains were isolated in a limited number of patients treated with SQV alone (3/13). The rates of emergence of resistant strains during ZDV or SQV monotherapies are comparable. Combination therapy may delay the emergence of phenotypic resistance to either drugs in the short term and to ZDV, but not to SQV, at least after 1 year.     

Postoperative analgesia with intramuscular morphine at fixed rate versus epidural morphine or sufentanil and bupivacaine in patients undergoing major abdominal surgery

Hydrofluoroalkane-134a (HFA) beclomethasone dipropionate (BDP) was formulated in a metered-dose inhaler (MDI) to deliver a particle size of 1.1 microm compared with 35 microns for currently marketed chlorofluorocarbon (CFC)-BDP products. Two phase I single-dose human deposition studies were conducted using technetium 99m-radiolabelled BDP in a press-and-breathe actuator without an add-on spacer. A healthy volunteer study (n=6) showed that 55-60% of the HFA-BDP ex-actuator dose was deposited in the lungs, with 29-30% deposited in the oropharynx. CFC-BDP deposition was 4-7% in the lungs and 90-94% in the oropharynx. The pattern of deposition within the lung showed that HFA-BDP was spread diffusely throughout the lung airways, whereas CFC-BDP was confined to the central airways with little, if any, peripheral airway deposition. A second study with asthmatics (n=16) confirmed that 56% of the HFA-BDP dose was deposited in the airways, with 33% in the oropharynx. In conclusion, hydrofluoroalkane-134a-beclomethasone dipropionate deposition was much greater in the airways than chlorofluorocarbon-beclomethasone dipropionate, with a concomitant reduction in oropharyngeal deposition. The increased lung deposition efficiency of the hydrofluoroalkane propellant has led to a reduction in the amount of beclomethasone dipropionate needed to achieve a similar efficacy. The penetration of the hydrofluoroalkane to the small airways may provide asthma treatment not afforded by conventional chlorofluorocarbons.