Effect of single-dose dexmedetomidine on postoperative recovery after ambulatory ureteroscopy and ureteric stenting: a double blind randomized controlled study.

BACKGROUND: Ambulatory surgery has recently gain popularity, as it is a good method of optimizinghospital resources utilization. To support ambulatory surgery, anaesthetic goals nowrevolve around patients' early recovery with minimal pain and nausea, expedientdischarge home and prompt resumption of activities of daily living. In this study, weevaluated the effect of a single pre-induction dose of dexmedetomidine on anaestheticrequirements, postoperative pain and clinical recovery after ambulatory ureteroscopy andureteric stenting under general anaesthesia. METHODS: Sixty patients were randomised to receive IV dexmedetomidine 0.5 µg.kg-1 (Group DEX, n = 30) or IV saline (Group P, n = 30). General anaesthesia was maintained with Sevoflurane: oxygen: air, titrated to BIS 40-60. Pain intensity, sedation, rescue analgesics, nausea/vomiting and resumption of daily activities were recorded at 1 h, and postoperative day (POD) 1-5. RESULTS: Group DEX patients had significant reduction in sevoflurane minimum alveolar concentration (MAC), mean (SD) DEX vs. Placebo 0.6 (0.2) vs. 0.9 (0.1), p = 0.037; reduced postoperative resting pain at 1 h (VAS 0-10) (mean (SD) 1.00 (1.84) vs. 2.63 (2.78), p = 0.004), POD 1 (mean (SD) 1.50 (1.48) vs. 2.87 (2.72), p = 0.002), POD 2 (0.53 (0.97) vs. 1.73 (1.96), p = 0.001) and POD 3 (0.30 (0.75) vs. 0.89 (1.49), p = 0.001). DEX patients also had less pain on movement POD 1 (3.00 (2.12) vs. 4.30 (3.10), p = 0.043) and POD 2 (2.10 (1.98) vs. 3.10 (2.46), p = 0.040), with higher resumption of daily activities by 48 h compared to placebo, 87% vs. 63%, p = 0.04. CONCLUSIONS: We conclude that a single dose of dexmedetomidine was a useful adjuvant in reducing MAC and postoperative pain (at 1 h and POD 1-3), facilitating faster return to daily activities by 48 h. TRIAL REGISTRATION: The Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617001120369 , 31st July 2017, retrospectively registered.

Ambu® AuraGain™ versus LMA Supreme™ Second Seal™: a randomised controlled trial comparing oropharyngeal leak pressures and gastric drain functionality in spontaneously breathing patients.

Newer second generation supraglottic airway devices may perform differently in vivo due to material and design modifications. We compared performance characteristics of the Ambu® AuraGain™ and LMA Supreme™ Second Seal™ in 100 spontaneously breathing anaesthetised patients in this randomised controlled study. We studied oropharyngeal leak pressures (OLP) (primary outcome) and secondarily, ease of insertion, success rates, haemodynamic response, time to insertion, and complications of usage. We found no significant difference in OLP between the AuraGain versus the LMA Supreme, mean (standard deviation, SD) 24.1 (7.4) versus 23.6 (6.2) cmH2O, P=0.720. First-attempt placement rates of the AuraGain were comparable to the LMA Supreme, 43/50 (86%) versus 39/50 (78%), P=0.906, with an overall 98% insertion success rate for the AuraGain and 88% for the LMA Supreme after three attempts, P=0.112. However, the AuraGain was deemed subjectively harder to insert, with only 24/50 (48%) versus 37/50 (74%) of AuraGain insertions being scored 1 = easy (on a 5 point scale), P=0.013, and also took longer to insert, 33.4 (SD 10.9) versus 27.3 (SD 11.4) seconds, P=0.010. The AuraGain needed a smaller volume of air (16.4 [SD 6.8] versus 23.0 [SD 7.4] ml, P <0.001) to attain intracuff pressures of 60 cmH2O, facilitated more successful gastric tube insertion (100% versus 90.9%, P=0.046), and had significantly decreased sore throat incidence (10% versus 38%, P=0.020). One AuraGain and six LMA Supremes failed to be placed within the stipulated 120 seconds trial definition of 'success'; these patients had risk factors for failed supraglottic insertion. In conclusion, both devices had similar OLPs and performed satisfactorily. However, the AuraGain resulted in less postoperative sore throat despite being harder to and taking longer to, insert.

Ultrasonographic identification of the cricothyroid membrane: best evidence, techniques, and clinical impact.

Inability to identify the cricothyroid membrane by inspection and palpation contributes substantially to the high failure rate of cricothyrotomy. This narrative review summarizes the current evidence for application of airway ultrasonography for identification of the cricothyroid membrane compared with the clinical techniques. We identified the best-documented techniques for bedside use, their success rates, and the necessary training for airway-ultrasound-naïve clinicians. After a short but structured training, the cricothyroid membrane can be identified using ultrasound in difficult patients by previously airway-ultrasound naïve anaesthetists with double the success rate of palpation. Based on the literature, we recommend identifying the cricothyroid membrane before induction of anaesthesia in all patients. Although inspection and palpation may suffice in most patients, the remaining patients will need ultrasonographic identification; a service that we should aim at making available in all locations where anaesthesia is undertaken and where patients with difficult airways could be encountered.

A randomised cross-over comparison of the transverse and longitudinal techniques for ultrasound-guided identification of the cricothyroid membrane in morbidly obese subjects.

We compared the transverse and longitudinal approaches to ultrasound-guided identification of the cricothyroid membrane, to determine which was faster and more successful. Forty-two anaesthetists received a one-hour structured training programme consisting of e-learning, a lecture and hands-on training, and then applied both techniques in a randomised, cross-over sequence to obese females with body mass index 39.0 - 43.9 kg.m(-2) . The mean (SD) time to identify the cricothyroid membrane was 24.0 (12.4) s using the transverse technique compared with 37.6 (17.9) s for the longitudinal technique (p = 0.0003). Successful identification of the cricothyroid membrane was achieved by 38 (90%) anaesthetists using either technique. All anaesthetists were successful in identifying the cricothyroid membrane with at least one of the techniques. We advocate the learning and application of these two techniques for identification of the cricothyroid membrane before starting anaesthesia in difficult patients, especially when anatomical landmarks are impalpable. Further use in emergency situations is feasible, if clinicians have experience and the ultrasound machine is readily available.

Effect of sitting position on equal-dose spinal anaesthetic for caesarean section and post-partum tubal ligation.

BACKGROUND: We studied the hypothesis that an equal spinal anaesthetic dose administered in the sitting position to patients undergoing post-partum tubal ligation (PPTL) and caesarean section (CS) would yield similar sensory block characteristics and analgesic efficacy. METHODS: This prospective, non-randomised trial recruited 20 women undergoing PPTL within 48 h of vaginal delivery and 20 undergoing CS. Spinal anaesthesia comprising intrathecal hyperbaric bupivacaine 12 mg and morphine 100 µg was administered at L3/4 with patients sitting. Our primary end point was the maximal dermatomal sensory block (to cold). RESULTS: Baseline demographics were comparable, but PPTL patients had greater parity, with mean ± standard deviation 17.54 ± 11.2 h from delivery to spinal anaesthesia, and shorter duration of surgery, 17.54 ± 11.2 vs. 40.3 ± 15.5 min. Similar maximal sensory blocks (to cold) were achieved in group PPTL vs. CS, T4 (T1-T5) vs. T3 (T1-T5), P = 0.104, in comparable times, 8.6 ± 2.6 vs. 7.6 ± 3.0 min, P = 0.267. PPTL patients had significantly faster two-segment block regression (70.7 ± 23.5 vs. 97.6 ± 23.9 min, P = 0.001) and to T10 (120.8 ± 35.6 vs. 145.1 ± 24.3 min, P = 0.016), with less hypotension (25% vs. 65%, P = 0.025) and phenylephrine (20.0 ± 60.6 µg vs. 120.0 ± 119.6 µg, P = 0.005). CONCLUSION: The same dose of hyperbaric bupivacaine 12 mg and morphine 100 µg administered in the sitting position to both PPTL and CS parturients yielded similar maximal sensory blocks, but PPTL exhibited faster block regression and less hypotension/vasopressor requirement.

Ruptured uterine artery pseudoaneurysm: an overlooked cause of late postpartum haemorrhage.

We report an exceptional case of secondary postpartum hemorrhage (PPH) twenty days after cesarean delivery, resulting from a ruptured uterine artery pseudoaneurysm (UAP). The diagnosis was initially confounded by a septic shock necessitating inotropic support in the intensive care unit. Intense vaginal bleeding occurred eleven days after uterine curettage. Doppler ultrasound showed an anechoic focus in the inferior part of the uterus with turbulent flow. Bilateral internal iliac artery angiograms revealed a left uterine artery pseudoaneurysm that was successfully embolized. UAP is a rare cause of unexplained PPH that requires a high index of suspicion for diagnosis. This first report in the anesthesia literature serves to focus our awareness on its possible occurrence, and gives track to its management. Pitfalls in UAP diagnostic are highlighted (delayed presentation, possibility of spontaneous hemostasis, and lack of typical findings on colour Doppler sonography in hypotensive patients). These pitfalls may further be confounded by a concomitant sepsis. Angiography and selective uterine artery embolization is the treatment of choice.

Observations on the assessment and optimal use of videolaryngoscopes.

Due to the large number of videolaryngoscopes now available, it might be difficult for novice users to assess the various devices or use them optimally. We have collated the experiences of several airway management experts to assist in the assessment and optimal use of seven commonly used videolaryngoscopes. While all videolaryngoscopes have unique features, they can be broadly divided into those inserted via a midline approach over the tongue and those inserted laterally along the floor of the mouth. Videolaryngoscopes that are placed on the floor of the mouth displace the tongue antero-laterally and flatten the submandibular tissues. They generally require a conventional shaped bougie for tracheal intubation. Videolaryngoscopes that use the midline approach may have an in-built airway conduit for the tracheal tube or may require a 'J-shaped' stylet in the tracheal tube to negotiate the upper airway. This may cause difficulty when the tracheal tube is inserted through the glottis and the tip abuts the anterior wall of the subglottic space. Knowledge of the mechanism used by videolaryngoscopes to achieve laryngoscopy is essential for safe and successful tracheal intubation when using these devices.

Comparison of the LMA Supreme vs the i-gel in paralysed patients undergoing gynaecological laparoscopic surgery with controlled ventilation.

We compared the efficacy of the inflatable cuff of the LMA Supreme against the non-inflatable i-gel cuff in providing an adequate seal for laparoscopic surgery in the Trendelenburg position in 100 female patients. There was no difference in our primary outcome, oropharyngeal leak pressure, between the LMA Supreme and the i-gel (mean (SD) 26.4 (5.1) vs 25.0 (5.7) cmH(2) O, respectively; p = 0.18). Forty-seven (94%) LMA Supremes and 48 (96%) i-gels were successfully inserted on the first attempt, with similar ease, and comparable times to the first capnograph trace (mean (SD) 14.3 (4.7) s for the LMA Supreme vs 15.4 (8.2) s for the i-gel; p = 0.4). Gastric tube insertion was easier and achieved more quickly with the LMA Supreme vs the i-gel (9.0 (2.5) s vs 15.1 (7.3) s, respectively; p < 0.001). After creation of the pneumoperitoneum, there was a smaller difference between expired and inspired tidal volumes with the LMA Supreme (21.5 (15.2) ml) than with the i-gel (31.2 (23.5) ml; p = 0.009). There was blood on removal of two LMA Supremes and one i-gel. Four patients in the LMA Supreme group and one patient in the i-gel group experienced mild postoperative sore throat.

Comparison of three videolaryngoscopes: Pentax Airway Scope, C-MAC, Glidescope vs the Macintosh laryngoscope for tracheal intubation.

We compared the intubating characteristics of the Pentax Airway Scope, the C-MAC and the Glidescope with those of the Macintosh laryngoscope in 400 patients without predictors of difficult intubation. We found shorter intubation times with the Airway Scope (mean (SD) 20.6 (11.5) s) compared with the C-MAC (31.9 (17.6) s) and Glidescope (31.2 (15.0) s), p < 0.001. The median (IQR [range]) score for ease of intubation was significantly lower (better) with the Airway Scope (0 (0-8.75 [0-60])) than with the C-MAC (10 (0-20 [0-90])) or Glidescope (0 (0-20 [0-80])), p < 0.001. Ease of blade insertion in the C-MAC (0 (0-0 [0-30])) was superior to that of the Airway Scope (0 (0-0 [0-70])), Macintosh (0 (0-0 [0-80])) or Glidescope (0 (0-10 [0-60])), p = 0.006. More patients had a grade 1 laryngeal view with the Airway Scope (97%) compared with the C-MAC (87%), Glidescope (78%), or Macintosh (58%), p < 0.001. There were no grade 3 laryngeal views with the Airway Scope. The three videolaryngoscopes had comparable first attempt successful intubation rates: 95% for the Airway Scope, 93% for the C-MAC and 91% for the Glidescope.

A prospective, randomised, cross-over trial comparing the EndoFlex and standard tracheal tubes in patients with predicted easy intubation.

We aimed to determine if using the EndoFlex tracheal tube on the first intubation attempt provided improved placement times and intubation success compared with a standard-type tracheal tube in 50 patients undergoing gynaecological surgery in a prospective, randomised, cross-over trial. We found that using the EndoFlex resulted in shorter intubation times (mean (SD) 14.8 (9.7) vs 30.1 (30.5) s), easier intubation (VAS, median (range) 10 (0-70) vs 20 (0-100)), and an increased rate of successful insertion at the first attempt; all p < 0.001. Flexing the distal tip of the EndoFlex was used in 18 patients. There were reductions in the use of external laryngeal pressure, advancement of laryngoscope blade and increased lifting force when intubating with the EndoFlex. Furthermore, patients with a grade 2 (19/50) or 3 (6/50) laryngoscopic view had shorter intubation times, easier intubation and reduced insertion attempts with the EndoFlex. The EndoFlex is a satisfactory alternative to a standard-type tracheal tube, even with an anterior larynx.

Randomised comparison of Pentax AirwayScope and Glidescope for tracheal intubation in patients with normal airway anatomy.

SUMMARY: We compared intubating characteristics of the Pentax AirwayScope and Glidescope in a randomised controlled trial involving 140 patients. We found significantly shorter intubation times with mean (SD) 21.3 (12.3) vs 30.2 (13.2) s, lower intubating difficulty scores 4.4 (10.4) vs 12.8 (16.3) p < 0.001, and better grade 1 laryngeal views with the Pentax AirwayScope (95.7 vs 81.4%, p = 0.015). Significantly more optimisation manoeuvres were needed to successfully intubate with the Glidescope, with significant inability to align the tip of the tracheal tube with the glottic opening with the Glidescope in 9 (13%) vs no patients, p = 0.013. There was more mucosal bleeding (4 (5.7%) vs 1 (1.4%), p = 0.366), more lip bleeding (3 (4.3%) vs 1 (1.4%), p = 0.620) and significantly more postoperative sorethroat, 13 (18.6%) vs 0, p < 0.001 associated with the Glidescope.

Comparison of an equal-dose spinal anesthetic for cesarean section and for post partum tubal ligation.

BACKGROUND: We postulated that a spinal dose of hyperbaric bupivacaine 12 mg and morphine 100 microg administered for cesarean section would yield an equivalent sensory block height and provide sufficient analgesia if administered within 48 h of delivery for postpartum tubal ligation. METHOD: 20 women undergoing postpartum tubal ligation (PPTL) within 48 h of vaginal delivery and 20 undergoing cesarean section (CS) were recruited. Spinal anesthesia was induced with intrathecal hyperbaric bupivacaine 12 mg and morphine 100 microg at L3/4 with patients in the right lateral position. RESULTS: Baseline demographics of groups were comparable, but tubal ligation patients had greater parity, with a mean+/-SD 14.5+/-7.5 h from delivery to spinal anesthesia, and shorter duration of surgery, 21.4+/-7.6 vs. 35.3+/-11.3 min. Maximal sensory block was higher in group CS than PPTL, T2 (T1-T4) vs. T3 (T2-T5), P=0.001; time to reach maximal level did not differ significantly, (6.9+/-3.9 vs. 8.7+/-2.8 min, P=0.091). There was no difference in time for spinal block to recede two segments or to T10, and for motor block recovery to Bromage 2, all P>0.05. More CS patients were hypotensive (80% vs. 45%, P=0.048) and had intraoperative nausea (25% vs. 0%, P=0.047), but mean phenylephrine and ephedrine usage did not differ significantly. CONCLUSION: An equivalent dose of hyperbaric bupivacaine 12 mg and morphine 100 microg for both CS and PPTL resulted in a higher sensory block, more hypotension and nausea in CS patients. The studied regimen might be appropriate for PPTL, but appears excessive for CS.

Comparison of the single use and reusable intubating laryngeal mask airway.

We compared the times to intubate the trachea using the single use (Group S) and reusable (Group C) intubating laryngeal mask (ILMA(TM)), in 84 healthy patients with normal airways undergoing elective gynaecological surgery. There was no significant difference in the ease of insertion of the ILMA or the tracheal tube, or time to successful insertion (Group S, 101.4 s (SD 63.2) vs Group C, 90.4 s (SD 46.1), p = 0.366). The ILMA was successfully inserted on first attempt in 63% of Group S patients and in 68% of Group C patients. After one or two attempts the overall success rate for both groups was 93%. There was a failure to insert the ILMA in two patients in each group. There was no difference in side-effects (desaturation S(p)o(2) < 95%, bleeding, oesophageal intubation, lip, dental or mucosal injury, or sore throat postoperatively). We conclude that the disposable ILMA is an acceptable alternative to the reusable ILMA.