BACKGROUND AND OBJECTIVES: To quantify the motor threshold current of a needle following elicitation of paresthesia during axillary brachial plexus block (ABPB). METHODS: This is a prospective, observational study of ABPB in 72 patients. Having elicited paresthesia, the minimum current required to produce a motor response was noted. The development and success of the block were subsequently followed. RESULTS: Nineteen blocks were excluded (18 because of arterial puncture and 1 blocked needle). Of the remaining 53 blocks, 41 (77%) produced a motor response at 0.5 mA or less. The median current was 0.17 mA (range, 0.03 to 3.3 mA). The site of initial paresthesia and subsequent motor response were related in 43 (81%) of cases. CONCLUSIONS: A needle position causing paresthesia produced a motor response at 0.5 mA or less in 77% of cases studied. This current may, therefore, be a reasonable threshold to aim for when performing an ABPB.

Anesthetics, Local↗

PubMedDate not supplied

Analgesic effects of low-dose ropivacaine for interscalene brachial plexus block for outpatient shoulder surgery-a dose-finding study.

BACKGROUND AND OBJECTIVES: Interscalene brachial plexus block (ISB) with low-dose bupivacaine provides effective postoperative shoulder analgesia in outpatients. The analgesic effect of low-dose ropivacaine for ISB is unknown. METHODS: In this double-blind study, 66 outpatients scheduled to undergo arthroscopic shoulder surgery were randomly assigned to receive an ISB with 10 mL of 0.125%, 0.25%, or 0.5% ropivacaine before surgery. Postoperative verbal pain rating score, analgesic consumption, and the extent of motor and sensory block was assessed for 120 minutes after surgery. RESULTS: The degree of shoulder analgesia was dose dependent. Postoperative pain scores were lowest with 0.5% ropivacaine, and analgesic was not required in the hospital in 70% of the patients who received 0.25% and 0.5% ropivacaine, compared to 30% with 0.125% ropivacaine (P < .03). In the patients who required no analgesic in the hospital, the time to first oral analgesic at home was approximately 10 hours irrespective of ropivacaine concentration. Motor and sensory block distal to the elbow was detected in 25% of the patients in the 0.5% group but none in the 0.125% group. CONCLUSIONS: Interscalene brachial plexus block with low-dose ropivacaine, 10 mL of 0.25% and 0.5%, provides effective long-lasting shoulder analgesia in a majority of patients after arthroscopic surgery.

Adult↗

PubMedDate not supplied

Neurophysiology of cancer pain.

BACKGROUND: Recent basic science research has greatly added to our knowledge of pain mechanisms. Application of this knowledge to cancer pain syndromes has led to new and innovative approaches to cancer pain management. METHODS: The mechanisms involved in the three main cancer pain syndromes (somatic, visceral, and neuropathic) are reviewed, and various therapeutic options are discussed. RESULTS: Advances in knowledge in neurophysiology, neuroanatomy, and pharmacology have allowed a greater understanding of the peripheral and central mechanisms of pain. New drugs and interventional techniques based on this knowledge have improved the control of cancer pain. CONCLUSIONS: Understanding the neurophysiology of cancer pain promotes use of the most appropriate palliative measures for pain control.

Humans↗

PubMedDate not supplied

[The population of China and its development].

Explore the source record for details and available documents.

Asia↗

PubMedDate not supplied

Analgesic effect of interscalene block using low-dose bupivacaine for outpatient arthroscopic shoulder surgery.

BACKGROUND AND OBJECTIVES: Although interscalene brachial plexus block (ISBPB) is often used to provide anesthesia for arthroscopic shoulder surgery, its selective analgesic effect, provided by low-dose local anesthetic, has not been studied. We hypothesized that ISBPB using a low volume and low concentration of bupivacaine can provide effective postoperative analgesia for shoulder surgery without producing significant sensory or motor block elsewhere. METHODS: In this double-blind study, 30 outpatients scheduled to undergo shoulder arthroscopy were randomly assigned to receive either an ISBPB with 10 mL 0.125% bupivacaine with epinephrine 1:400,000 (n = 15) or 10 mL of normal saline (n = 15). The block was performed preoperative, prior to a standardized general anesthetic. Postoperative pain scores, imorphine and oral analgesic consumption, recovery profile, and patient satisfaction were recorded. RESULTS: In the ISBPB group, verbal analog pain scores within 120 minutes after surgery were lower, morphine consumption in the postanesthesia care unit was significantly lower (2.7+/-2.6 mg vs 9.5+/-5.2 mg), the time to postoperative administration of the first systemic or oral analgesic was significantly longer (141+/-182 minutes vs 13+/-10 minutes), the degree of motor and sensory block 120 minutes after surgery was minimal, time to reach hospital discharge criteria was earlier, and patient satisfaction with postoperative analgesia at 24-hour follow-up was greater. Thirty-three percent of the patients receiving ISBPB did not require any analgesic prior to hospital discharge. CONCLUSIONS: Interscalene brachial plexus block with low-dose bupivacaine is a useful and selective analgesic technique for outpatient shoulder arthroscopic surgery.

Adult↗