10% Lidocaine spray as a local anesthetic in blood gas sampling: A randomized, double-blind, placebo-controlled study

AIM

Radial artery blood gas sampling is a very common procedure undertaken in the emergency department to evaluate respiratory and metabolic parameters. This intervention causes both anxiety and pain for the patient. Therefore, the current study aimed to examine the analgesic efficacy of lidocaine spray compared to a placebo during radial artery blood gas sampling.

METHODS

This study was conducted in the emergency department of a tertiary hospital with a randomized, double-blind, placebo-controlled design. A total of 144 patients were randomly divided into two groups: One group (n = 72) received 10% lidocaine spray and the other (n = 72) was the placebo group. The analgesic efficacy of the 10% lidocaine spray was compared with the placebo group using the Visual Analog Scale (VAS).

RESULTS

In the evaluation of the analgesic efficacy of the 10% lidocaine spray, the VAS score was 1.5 [interquartile range (IQR): 2.0] for the lidocaine group and 5 (IQR: 2.0) for the placebo group. The role of lidocaine spray in reducing pain was statistically significant compared to the placebo (p = 0.000).

CONCLUSION

In blood gas sampling, 10% lidocaine spray has analgesic efficacy. Therefore, we recommend the use of lidocaine spray while performing arterial blood gas sampling in emergency departments.

How to minimize the pain of local anesthetic administration

Expertise in the delivery of effective local analgesia is critical to the success of in-office procedures. Here's how to optimize patient outcomes and satisfaction.

Comprehensive evidence-based guidelines for interventional techniques in the management of chronic spinal pain

BACKGROUND

Comprehensive, evidence-based guidelines for interventional techniques in the management of chronic spinal pain are described here to provide recommendations for clinicians.

OBJECTIVE

To develop evidence-based clinical practice guidelines for interventional techniques in the diagnosis and treatment of chronic spinal pain.

DESIGN

Systematic assessment of the literature.

METHODS

Strength of evidence was assessed by the U.S. Preventive Services Task Force (USPSTF) criteria utilizing 5 levels of evidence ranging from Level I to III with 3 subcategories in Level II.

OUTCOMES

Short-term pain relief was defined as relief lasting at least 6 months and long-term relief was defined as longer than 6 months, except for intradiscal therapies, mechanical disc decompression, spinal cord stimulation and intrathecal infusion systems, wherein up to one year relief was considered as short-term.

RESULTS

The indicated evidence for accuracy of diagnostic facet joint nerve blocks is Level I or II-1 in the diagnosis of lumbar, thoracic, and cervical facet joint pain. The evidence for lumbar and cervical provocation discography and sacroiliac joint injections is Level II-2, whereas it is Level II-3 for thoracic provocation discography. The indicated evidence for therapeutic interventions is Level I for caudal epidural steroid injections in managing disc herniation or radiculitis, and discogenic pain without disc herniation or radiculitis. The evidence is Level I or II-1 for percutaneous adhesiolysis in management of pain secondary to post-lumbar surgery syndrome. The evidence is Level II-1 or II-2 for therapeutic cervical, thoracic, and lumbar facet joint nerve blocks; for caudal epidural injections in managing pain of post-lumbar surgery syndrome, and lumbar spinal stenosis, for cervical interlaminar epidural injections in managing cervical pain (Level II-1); for lumbar transforaminal epidural injections; and spinal cord stimulation for post-lumbar surgery syndrome. The indicated evidence for intradiscal electrothermal therapy (IDET), mechanical disc decompression with automated percutaneous lumbar discectomy (APLD), and percutaneous lumbar laser discectomy (PLDD) is Level II-2.

LIMITATIONS

The limitations of these guidelines include a continued paucity of the literature, lack of updates, and conflicts in preparation of systematic reviews and guidelines by various organizations.

CONCLUSION

The indicated evidence for diagnostic and therapeutic interventions is variable from Level I to III. These guidelines include the evaluation of evidence for diagnostic and therapeutic procedures in managing chronic spinal pain and recommendations for managing spinal pain. However, these guidelines do not constitute inflexible treatment recommendations. Further, these guidelines also do not represent "standard of care."

The efficacy of 0.5% proparacaine stored at room temperature

OBJECTIVE

To evaluate the efficacy of 0.5% proparacaine stored at room temperature for 6 weeks.

ANIMALS STUDIED

Six normal dogs, evaluated on a weekly basis for 6 weeks.

PROCEDURE

Proparacaine stored at 4 degrees C or at room temperature, was evaluated in the right and left eye of each dog, respectively. Corneal sensitivity was assessed with a Cochet-Bonnet aesthesiometer before and after instillation of proparacaine at each time point.

RESULTS

A statistically significant difference was seen in corneal sensitivity beginning at week 3 for the eyes receiving room-temperature proparacaine compared to refrigerated proparacaine. Differences were not seen between right and left eyes before instillation of proparacaine for any time point, nor for eyes receiving refrigerated proparacaine over the 6 week study period.

CONCLUSION

Short-term storage of proparacaine at room temperature did not affect efficacy, but storage at room temperature for more than 2 weeks resulted in a decrease in drug effect.

Dispersal of radioisotope labelled solution following deep dermal injection in Ehlers-Danlos syndrome

Ehlers-Danlos syndrome (EDS) is the commonest inherited disorder of connective tissue, affecting around 10 000 patients in the UK. Patients with EDS have reported that local anaesthetic is often ineffective. Patients with less severe skin laxity often have the most problems. We have postulated that this resistance to local anaesthetics is not due to the lax connective tissues as is often assumed. This study used radioactively labelled solution ((99m)Tc-pertechnetate) administered as a deep dermal injection in the forearm. The rate of dispersal of isotope was measured over 60 min and found to be identical between six patients with EDS and three controls. The effects of local anaesthetics are complex and depend on the individual chemical properties of the agent and a number of tissue factors. This study would suggest that the lack of effectiveness of local anaesthetic solutions is not due to rapid dispersal of solution. It is unlikely therefore that its lack of effect can be compensated for by simply increasing the amount used. The diagnosis of EDS should be considered in any patient who complains unexpectedly of pain during their procedure, particularly when the surgeon knows that an adequate volume of local anaesthetic has been used.

Topical anaesthesia for cataract surgery

First, do no harm. We believe that the analgesia provided by topical anaesthetic is adequate for small-incision cataract surgery and does not compromise the safety of the surgery. In addition, the lack of amaurosis is ideal for day-case surgery, which itself is increasingly popular. If preventable, why not prevented? The greatest attraction of topical anaesthesia is its complete absence of the complications described for injectional local anaesthetic techniques. We therefore recommend that our colleagues consider topical anaesthetic for patients undergoing small-incision cataract surgery under local anaesthesia. Our policy for the past 3 years has been to use only topical or general anaesthetics for cataract surgery.

Stability of bupivacaine hydrochloride with diamorphine hydrochloride in an epidural infusion

The stability of diamorphine (0.02 mg/ml as the hydrochloride) in 250 ml bupivacaine hydrochloride (0.15% wt/vol infusion) was studied by high pressure liquid chromatography at temperatures in the range 7 to 45 degrees C. Diamorphine hydrochloride was degraded by approximately 0.13% per day at 7 degrees C. No bupivacaine hydrochloride degradation was detectable during the study. The storage life of the combination at 7 degrees C, based on the lower 95% confidence limit of the time to 5% diamorphine hydrochloride degradation, was 14 days. The stability at 25 degrees C was adequate to allow transport and administration over 24 h at ambient temperature. Stability was also maintained for at least 24 hr at 32 and 45 degrees C. Infusion of the mixture with an ambulatory infusion pump which uses a standard polyvinyl infusion bag is therefore possible. A study of its compatibility with different infusion pump medication reservoirs was not undertaken. The drugs were also stable on frozen storage at -18 degrees C for up to 6 months.

Labor pain relief using bupivacaine and sufentanil: patient controlled epidural analgesia versus intermittent injections

OBJECTIVES

To determine whether the use of patient-controlled epidural analgesia (PCEA) versus intermittent injections (CIT) resulted in local anesthetic dose reduction.

STUDY DESIGN

PCEA and CIT using a mixture of 0.125% bupivacaine with sufentanil 1 or 0.75 microgram/ml were compared in 60 and 195 parturients, respectively. Assessments included pain scores, local anesthetic consumption, degree of motor blockade, type of delivery and neonatal outcome. Statistical analysis was done using Student's t test and Chi-squares.

RESULTS

PCEA and CIT provided effective analgesia during labor and delivery. A higher dose of opioid significantly reduced the use of local anesthetic solution in PCEA-patients. There was no difference in motor blockade, type of delivery and neonatal outcome.

CONCLUSION

Patient-controlled epidural analgesia is an effective, safe and acceptable alternative to conventional intermittent epidural injections for pain relief during labor and delivery.

Issues in the selection of local anesthetics

Several factors influence the safety with which neural blockade is performed, and something as simple as proper packaging can make a significant difference. For example, bulk packaging, individual boxes, and labels all should be color coded for easy identification and to alert the prescriber of ingredients requiring particular caution. One must also take care not to confuse single-use with multiple-use products, if the latter cannot be eliminated from formulary. Furthermore, substitutions must be made properly, particularly to avoid complications associated with products that contain preservatives.

Efficacy of topical anaesthetics

By means of a recently developed electronical optical esthesiometer the efficacy of five different topical anaesthetics was compared. The influence of vehicle and concentration was also investigated. From the results it can be concluded that the drugs currently available are of suitable local anaesthetic effect with little influence of the vehicle or preservative agent used.

Fluress, fluorescein and benoxinate: recovery from bacterial contamination

The ability to recover from bacterial contaminations with Staphylococcus auresus and Pseudomonas aeruginosa was determined for three optometric DPAs: Fluress, fluorescein and benoxinate. Results show that Fluress recovers from contamination more rapidly than benoxinate or fluorescein. This ability to recover from contamination and the relative ease of use of Fluress may make it the DPA choice for a number of optometric procedures including applanation tonometry.

[Comparative tests of tetracian and of the new local anesthetic carticain in spinal anesthesiasa double placebo study]

Onset of effect, degree of effect and duration of effect of Tetracain (Pantocain) and Carticain (Ultracain) in hyperbaric solutions were compared on 60 subjects with spinal anesthesias. In the double-blind trial with individual randomization, no difference was found regarding the onset of action (latency period), the intensity of analgesia and the extent of the muscle blocking. With 151 +/- 48.9 min., the duration of analgesia with Carticain was distinctly and significantly shorter than in the case of Tetracain with 278 +/- 108.9 min., but thoroughly sufficient for the nature and duration of the surgical operations on pour patients, even in the postoperative phase.

[Toxicity tests in vasoconstrictor agents added to local anesthetics]

The toxicities of adrenalin, nor-adrenalin and vasopressin derivatives were compared on the basis of animal tests, among others. The adrenalin additive is rejected.

Determination of procaine and related local anesthetics. II. Collaborative study

The ion-pairing chromatographic method reported previously for the isolation and spectrophotometric determination of the local anesthetics, alone and in combination, was studied collaboratively. Three solutions were assayed. One containing procaine as the single active component gave an average recovery of 99.8 plus or minus 1.7%. A mixture of procaine and tetracaine gave results of 99.3 plus or minus 1.6 and 98.9 plus or minus 8.82%, respectively. A third solution containing procaine and propoxycaine assayed 100.0 plus or minus 1.5 and 99.1 plus or minus 1.9%, respectively. It was shown that low results for tetracaine were due to loss during the final evaporative step. The method for samples containing tetracaine should be studied further. The other methods have been adopted as official first action.