Comparing S-Guide® and Gliderite® Times to Assist Video laryngoscopic Intubation in Patients with Simulated Difficult Airways: A Single-Blinded Randomized Prospective Study.

OBJECTIVE: Gliderite®, one of the first stylets designed specifically to assist tracheal intubation with non-channeled curved blades video laryngoscopes, can cause injury. The S-Guide® is a new, malleable, intubating guide allowing oxygenation. Its soft tip is designed to prevent trauma. We aimed to compare the duration of tracheal intubation with S-Guide compared to Gliderite using a C-MAC® D-Blade® video laryngoscope in patients with simulated difficult airways. METHODS: We performed a single-blinded prospective randomized study, with 50 adult patients requiring orotracheal intubation under general anaestheesia in Lausanne University Hospital. A cervical collar was fitted around the patient's neck to simulate difficult intubation conditions. Exclusion criteria were American Society of Anesthesiologists (ASA) >3, BMI > 35 kg m2 , known or at risk of difficult intubation, and risk of aspiration of gastric content. We recorded T1: time of identification of the glottis; T2: time to inflate the cuff, and T3: total intubation time (capnography curve appearance). Secondary outcomes were the presence of arytenoid contact during intubation and postoperative airway discomfort. RESULTS: There were no significant differences between T1 and T2 (seconds) while using the S-Guide or Gliderite, respectively: 14.6 [9.6- 18.6] vs 16.5 [11.0-20.6]; P=.368 and 43.3 [33.2-49.3] vs 46.3 [35.6-61.5], P =.308. T3 was significantly shorter in the S-Guide group: 58.1 [50.2-61.8] vs 65.3 [57.6-78.7], P =.044. Fewer arytenoid contact occurred during intubation using the S-Guide (P =.032), without difference in postoperative airway discomfort. CONCLUSION: S-Guide-assisted tracheal intubation, with a C-MAC D-Blade in simulated difficult airways, allows successful and faster intubation than with the Gliderite Stylet.

Bedside cerebral microdialysis monitoring of delayed cerebral hypoperfusion in comatose patients with poor grade aneurysmal subarachnoid haemorrhage.

BACKGROUND: Delayed cerebral ischaemia (DCI) is frequent after poor grade aneurysmal subarachnoid haemorrhage (SAH). Owing to the limited accuracy of clinical examination, DCI diagnosis is often based on multimodal monitoring. We examined the value of cerebral microdialysis (CMD) in this setting. METHODS: 20 comatose SAH participants underwent CMD monitoring-for hourly sampling of cerebral extracellular lactate/pyruvate ratio (LPR) and glucose-and brain perfusion CT (PCT). Patients were categorised as DCI when PCT (8±3 days after SAH) showed cerebral hypoperfusion, defined as cerebral blood flow <32.5 mL/100 g/min with a mean transit time >5.7 s. Clinicians were blinded to CMD data; for the purpose of the study, only patients who developed cerebral hypoperfusion in anterior and/or middle cerebral arteries were analysed. RESULTS: DCI (n=9/20 patients) was associated with higher CMD LPR (51±36 vs 31±10 in patients without DCI, p=0.0007) and lower CMD glucose (0.64±0.34 vs 1.22±1.05, p=0.0005). In patients with DCI, CMD changes over the 18 hours preceding PCT diagnosis revealed a pattern of CMD LPR increase (coefficient +2.96 (95% CI 0.13 to 5.79), p=0.04) with simultaneous CMD glucose decrease (coefficient -0.06 (95% CI -0.08 to -0.01), p=0.03, mixed-effects multilevel regression model). No significant CMD changes were noted in patients without DCI. CONCLUSIONS: In comatose patients with SAH, delayed cerebral hypoperfusion correlates with a CMD pattern of lactate increase and simultaneous glucose decrease. CMD abnormalities became apparent in the hours preceding PCT, thereby suggesting that CMD monitoring may anticipate targeted therapeutic interventions.