Loss Of Resistance Syringe Research Articles

Minimizing adverse effects of subjective measurement of endotracheal tube cuff pressure: Can the use of the loss of resistance technique help?

Background: Appropriate endotracheal tube cuff (ETTc) pressure estimation is essential to prevent airway complications. The pilot balloon palpation technique is the commonly used method of cuff inflation. It is however subjective thus prone to over or under estimation thus unreliable.
 Objective: To determine if the use of the passive release technique of cuff inflation would reduce commonly encountered airway complications following ETT intubation.
 Methodology: Patients scheduled for elective procedures under general anaesthesia with ETT were recruited into the study, 108 ASA I and II patients aged between 18-65 years were randomized into 2 groups with one group having their cuff inflated using the pilot balloon palpation (PBP) technique and the other by the use of a loss of resistance syringe (LOR). Airway complications were then assessed and compared between the 2 groups.
 Results: The incidences of sore throat, cough and hoarseness were significantly lower in the LOR group compared to the PBP group (35.2vs79.6%, 14.8 vs64.8% and 7.4 vs 79.6% respectively; p = 0.0001 in each case).
 Conclusion: Passive release technique using LOR was found to be less associated with post-endotracheal intubation airway complications than PBP technique

Investigating the use of non-loss of resistance syringes for epidural insertion: experience on a mannequin

IntroductionThe Obstetric Anaesthetists’ Association has released a statement outlining the disruption to supply of the Portex® Loss of Resistance Syringe (Smiths Medical, UK) which is commonly used for epidural insertion within our Trust. We sought to investigate the use of standard available syringes for epidural insertion and whether tactile feedback when getting loss of resistance was similar. MethodsUsing an epidural trainer model, we asked anaesthetists regularly working in the maternity unit to trial three alternative syringes (10 mL BD Emerald, 10 mL BD syringe from our epidural packs, and 20 mL BD Plastipak) (Becton Dickinson U.K. Limited, UK) and to complete a qualitative questionnaire about their experience. ResultsResponses from 16 anaesthetists, including individuals with a range of obstetric anaesthetic experience who regularly provide obstetric anaesthesia, were collected. With the BD Emerald 10 mL syringe, 81% considered there was no difference or only a slight difference when feeling for loss of resistance. For the BD 10 mL syringe, this figure was 75%. With the 20 mL syringe 66% reported either a reasonable or marked difference in tactile feel. The most popular syringe was the 10 mL BD Emerald syringe. ConclusionUsing an epidural training mannequin, this study suggests that it is still possible to elicit clear loss of resistance using alternative syringes. Of the three alternative syringes commonly available in our organisation, the BD Emerald 10 mL syringe was the most popular.

Randomized comparison of two methods of the epidural space identification during regional labour analgesia.

Conventional loss of resistance (LOR) technique for identifying the epidural space (EDS) predominantly depends on experience of the anaesthetist. A technique using automated syringe for EDS identification was invented as an alternative to the traditional method. The aim of the study was to compare the efficacy and risk for complications between automatic LOR syringe - Epimatic® (Vygon, Ecouen, France) and conventional LOR - Perifix® (B.Braun Melsungen AG, Melsungen, Germany) techniques for EDS identification. A total of 170 patients were enrolled into the study and 153 cases were analysed. Number of at- tempts, time to EDS identification, ease of EDS identification, complication rate and patient procedure-related discomfort were evaluated and compared. No statistically significant differences were found in the number of needle insertion attempts (1.3 in both groups), time to EDS identification (31 sec. vs. 27 sec.), efficacy of epidural analgesia (100% in both groups), or complication rate between both groups. The automatic and the conventional LOR techniques are comparable in terms of efficacy and safety for the epidural space identification.

A proposal of a simple epidural simulator for training novice anesthesiologists.

Confirming the epidural space during epidural anesthesia relies mainly on feel and experience, which are difficult techniques for a trainee to learn. We designed an epidural simulator for trainees to experience loss of resistance (LOR) and various degrees of pressure resistance. The simulator consists of a Perifix(®) LOR syringe and 1-, 5-, 10- and 50-mL syringes assembled by three-way stopcocks. A total of 89 anesthesiologists evaluated the simulator, given the choice of either the intermittent technique with air or continuous technique with saline. Sudden LOR and applicability of the simulator for training purposes were assessed using the numerical rating score (NRS). Pressure resistance at each lumbar structure was evaluated by the anesthesiologists using the intermittent technique with air. Seventy-four anesthesiologists used the intermittent technique with air and 15 used the continuous technique with saline. The NRSs for sudden LOR and the applicability for training purposes were 8 and 9 (median), respectively. The pressure resistance to a 50-mL syringe was regarded as the epidural space (odds ratio 602.3 for 5-mL syringe and 144.4 for 10-mL syringe) by 89% of anesthesiologists using air for LOR. Resistance to the 10-mL syringe was most frequently considered as muscle, subcutaneous fat, or the interspinous ligament, while resistance to the 1-mL syringe was considered as the ligamentum flavum (odds ratio 2.3 for 5-mL syringe and 18.6 for 10-mL syringe). Our epidural simulator is a simple, low-cost device that can be easily constructed. It was shown to provide valid haptic feedback as a promising tool for training novice anesthesiologists.

Identification of epidural space using loss of resistance syringe, infusion drip, and balloon technique: A comparative study.

Background and Objective:There are various techniques to identify epidural space but superiority of one technique over other has not been adequately studied. We conducted a study to Compare and evaluate the three techniques for epidural space localization that is, loss of resistance (LOR) syringe technique, balloon technique and drip infusion technique.Materials and Methods:Seventy-five patients of either sex, belonging to American Society of Anesthesiologists physical status Class 1 or 2, between 20 and 50 years of age, scheduled to undergo lower abdominal and lower limb surgeries were randomly allocated to one of the three groups (n = 25 each) depending upon epidural space localization. In Group I, epidural space localization was done with LOR syringe technique. In Group II Balloon technique and in Group III drip infusion technique was used. Distance of the epidural space from skin, number of attempts, time taken for epidural space localization and quality of the block were the parameter recorded during the study.Results:First attempt success rate for epidural space localization was highest in Group III (100%). The mean time taken for epidural space localization was least in Group III, and when compared with other groups it was found to be statistically significant with P = 0.016. Number of attempt for space localization and success rate of the block was better in the majority of patients of Group III, but the difference was found to be statistically nonsignificant. Complication rate was almost negligible in all three techniques.Conclusion:We conclude that the time taken to localize the epidural space was least in drip infusion technique. As for number of attempts, quality of the block and complications is concerned, all the three techniques are comparable.

Comparison of Spring-Loaded, Loss of Resistance and Hanging Drop Techniques in Lumbar Epidural Blocks

The spring-loaded syringe is a loss of resistance syringe that provide a more objective sign that the epidural space has been entered compared with the traditional techniques. The aim of this study was to compare the time required to locate the epidural space and the backache incidence with the spring-loaded (SL), loss of resistance (LOR) and the hanging drop (HD) techniques for epidural blocks in patients undergoing transurethral resection procedure. Sixty patients undergoing transurethral resections were enrolled in the study. The patients were randomly assigned to one of three groups. Epidural block was performed in the first group with a spring-loaded syringe (n=20), in the second group with loss-of-resistance syringe (n=20), and in the third group with the hanging drop technique (n=20). The required time to locate the epidural space, the number of attempts, the incidence of dural puncture and the backache incidence were assessed during the procedure and for four weeks after the procedure in all patients. The required time to locate the epidural space was 29.1 ± 9.16 seconds in Group 1; 45.25 ± 19.58 seconds in Group 2, and 47.35 ± 11.42 seconds in Group 3 (p<0.001). In Group 1 this was significantly shorter than the other two groups. There was no significant difference in the number of attempts, the incidence of dural puncture and backache incidence between the three groups (p>0.05). The use of SL syringe was found to have a shorter time period to locate the epidural space when compared with the LOR syringe and hanging drop technique.

Loss of Resistance to Saline Reduces Responses Accompanying Spinal Needle Insertion during Institution of ‘Needle-Through-Needle’ Combined Spinal-Epidural Analgesia

Normal saline or air is used to identify loss of resistance during identification of the epidural space for combined spinal-epidural analgesia. Following epidural needle placement using air for loss of resistance, up to 80% of parturients move, grimace, vocalise or experience paraesthesia or dysaesthesia during subsequent dural puncture by a spinal needle. We compared the effects of saline versus air for loss of resistance on the occurrence of these subjective and objective responses during thecal penetration. With institutional approval, 55 parturients presenting for labour analgesia were studied. After infiltration of lignocaine at an L2-L5 vertebral interspace, a 17 gauge Tuohy epidural needle attached to a 5 ml loss of resistance syringe containing either saline or air was inserted and advanced until loss of resistance was identified by injection of 3 to 5 ml of content. During subsequent 'needle-through-needle' insertion of a 27 gauge pencil-point spinal needle through the meninges, all subjective and objective patient responses were recorded, as well as each patient's reply to the question "Did you feel that?". The two groups (n = 28, n = 27) were comparable. In those given saline and air respectively, 5 (18%) and 12 (44%) parturients responded to and/or acknowledged having perceived dural puncture (P < 0.005). Overall, 7 and 31 (P < 0.0005) subjective and objective responses occurred during dural puncture in those given saline and air, respectively. The study found that use of saline to determine loss of resistance is associated with fewer patient responses at the moment of thecal penetration during 'needle-through-needle' placement of the spinal needle at combined spinal-epidural analgesia.

Real-time ultrasound-guided paramedian epidural access: evaluation of a novel in-plane technique

Current methods of locating the epidural space rely on surface anatomical landmarks and loss-of-resistance (LOR). We are not aware of any data describing real-time ultrasound (US)-guided epidural access in adults. We evaluated the feasibility of performing real-time US-guided paramedian epidural access with the epidural needle inserted in the plane of the US beam in 15 adults who were undergoing groin or lower limb surgery under an epidural or combined spinal-epidural anaesthesia. The epidural space was successfully identified in 14 of 15 (93.3%) patients in 1 (1-3) attempt using the technique described. There was a failure to locate the epidural space in one elderly man. In 8 of 15 (53.3%) patients, studied neuraxial changes, that is, anterior displacement of the posterior dura and widening of the posterior epidural space, were seen immediately after entry of the Tuohy needle and expulsion of the pressurized saline from the LOR syringe into the epidural space at the level of needle insertion. Compression of the thecal sac was also seen in two of these patients. There were no inadvertent dural punctures or complications directly related to the technique described. Anaesthesia adequate for surgery developed in all patients after the initial spinal or epidural injection and recovery from the epidural or spinal anaesthesia was also uneventful. We have demonstrated the successful use of real-time US guidance in combination with LOR to saline for paramedian epidural access with the epidural needle inserted in the plane of the US beam.

797: New Loss of Resistance Syringe for Labor Epidural Block

797: New Loss of Resistance Syringe for Labor Epidural Block

New Loss of Resistance Syringe for Labor Epidural Block

New Loss of Resistance Syringe for Labor Epidural Block

797. New Loss of Resistance Syringe for Labor Epidural Block

797. New Loss of Resistance Syringe for Labor Epidural Block

The Episure™ Syringe: A Novel Loss of Resistance Syringe for Locating the Epidural Space

The Episure syringe is a unique spring-loaded loss-of-resistance (LOR) syringe with a coaxial compression spring within a Portex Pulsator LOR syringe. This syringe supplies a constant pressure while the operator is advancing the Tuohy needle. We evaluated the syringe using an artificial model of the ligamentum flavum, an anesthetized pig, and women who desired epidural analgesia for labor. The operator, using the spring-loaded syringe, was able to stop the forward movement of the needle, so that compared with a standard LOR syringe less of the needle protruded out the back of the laboratory model. Satisfactory labor analgesia in the human study and radiograph analyses in the porcine model confirmed epidural placement in all attempts. The spring-loaded syringe is a potentially useful LOR syringe that provides a reliable, objective end-point for identification of the epidural space.