Can't intubate, can't oxygenate? What is the preferred surgical strategy? A retrospective analysis.

INTRODUCTION: Cricothyrotomy (CTM) is currently recommended as the preferred method due to its ease, speed, and safety in life-threatening airway emergencies where standard tracheal intubation and mask ventilation fail. MATERIAL AND METHODS: This retrospective study analyzed 33 cases of "can't intubate, can't oxygenate or ventilate" (CICOV): 12 of percutaneous dilatational tracheostomy (PDT) and 21 of CTM. The CTM group was younger (median age 44) and mainly consisted of trauma patients. The PDT group was more diverse and procedures were performed by anesthesia and critical care consultants. RESULTS: Initial success rates were 100% for PDT (12/12) and 86% for CTM (18/21), with one conversion from CTM to PDT. No perioperative complications occurred in the PDT group, while the CTM group experienced two cases of false tracts requiring re-do and three cases of bleeding. Immediate mortality within 24 hours was reported in 5/19 CTM patients and none in the PDT group. Successful liberation from mechanical ventilation at hospital discharge was achieved in 6/12 PDT patients and 11/21 CTM patients. Among the 21 CTM cases, all 16 survivors underwent subsequent tracheostomy. Tracheal decannulation occurred in 4/12 PDT patients and 10/21 CTM patients. Favorable immediate neurological outcomes (GCS ≥ 11T) were observed in 8/12 PDT patients and 8/21 CTM patients, while 3 PDT patients remained anesthetized until death and 7 CTM patients died within the first 72 hours without recovery attempts. CONCLUSIONS: In experienced hands, PDT could be a legitimate clinical option for the surgical airway in cases of CICOV. CTM may be more suitable for practitioners who encounter CICOV infrequently.

Peripheral Nerve Block to Treat Pain Caused by Daboia palaestinae Envenomation.

Snakebite pain can be challenging to control. We describe our experience managing intolerable pain after conventional treatment failed. A 35-year-old man, presented after a viper snakebite, suffering from intolerable pain in the affected extremity. He had no significant past medical history. All attempts to control the pain conventionally were unsuccessful. Treatment with a supraclavicular nerve block resulted in immediate relief. After the block receded, only a dull pain remained, which later disappeared without recurrence. This experience illustrates the need for personalized pain treatment to avoid subsequent complications.

Pre-intubation ventilation device for bearded patients: prospective, randomized, crossover trial in anesthetized patients.

Having a beard is an independent predictor of difficult ventilation by face mask. This study evaluates the efficacy of a novel intra-oral Bag-Valve-Guedel Adaptor (BVGA) in anaesthetized bearded patients. Patients with ASA score 1-2, scheduled for elective surgery, were recruited for this prospective, crossover trial. Beard length was categorized as < 0.5 cm, 0.5-1 cm, 1-5 cm, or > 5 cm. Patients were ventilated by attending anesthesiologists using the BVGA and a facemask (both with a Guedel oral airway). End-tidal CO2 (EtCO2) and expiratory tidal volume (TV) were recorded as was the number of hands required for the procedure. The primary outcome was the difference between BVGA and Facemask. Sixty-one patients were enrolled. Of these, 38 had beards, and 23 were without beards or with beards < 0.5 cm length. In bearded patients, ventilation with the BVGA was superior to the face mask by EtCO2 and non-inferior by TV (BVGA-vs-Mask, mean [95% CI]: EtCO2 [mmHg], 33.0 [31.6, 34.3]-vs-27.2 [25.5, 28.8], p < 0.001; TV [ml∙kg-1 IBW], 8.1 [7.4, 8.9]-vs-6.9 [6.0, 7.7], p = 0.11). The BVGA was found to be superior to the face mask by EtCO2 across all beard lengths (p ≤ 0.001), but by TV only for the longest beard group (p = 0.009). After securing the BVGA, ventilation was possible without hands in 74% of the cases - clearly impossible with the facemask (p ≤ 0.001). The BVGA is more effective and more convenient than the facemask in anaesthetized bearded patients. A follow-up study is underway to test whether replacing the face mask with the BVGA will improve effectiveness and ease of pre-intubation field ventilation by less-experienced, first responders.

Asleep DBS under ketamine sedation: Proof of concept.

BACKGROUND: Deep brain stimulation (DBS) is commonly and safely performed for selective Parkinson's disease patients. Many centers perform DBS lead positioning exclusively under local anesthesia, to optimize brain microelectrode recordings (MER) and testing of stimulation-related therapeutic and side effects. These measures enable physiological identification of the DBS borders and subdomains based on electrophysiological properties like firing rates and patterns, intra-operative evaluation of therapeutic window, and improvement of lead placement accuracy. Nevertheless, due to the challenges of awake surgery, some centers use sedation or general anesthesia, despite the distortion of discharge properties and interference with clinical testing, resulting in potential impact on surgical outcomes. Thus, there is a need for a novel anesthesia regimen that enables sedation without compromising intra-operative monitoring. OBJECTIVE: This open-label study investigates the use of low-dose ketamine for conscious sedation during microelectrode recordings and lead positioning in subthalamic nucleus (STN) DBS for Parkinson's disease patients. METHODS: Three anesthetic regimens were retrospectively compared in 38 surgeries (74 MER trajectories, 5962 recording sites) across three DBS centers: 1) Interleaved propofol-ketamine (PK), 2) Interleaved propofol-awake (PA), and 3) Fully awake (AA). RESULTS: All anesthesia regimens achieved satisfactory MER. Detection of STN borders and subdomains by expert electrophysiologist was similar between the groups. Electrophysiological signature of the STN under ketamine was not inferior to either control group. All patients completed stimulation testing. CONCLUSIONS: This study supports a low-dose ketamine anesthesia regimen for DBS which allows microelectrode recordings and stimulation testing that are not inferior to those conducted under awake and propofol-awake regimens and may optimize patient experience. A prospective double-blind study that would also compare patients' satisfaction level and clinical outcome should be performed to confirm these findings.

Toward asleep DBS: cortico-basal ganglia spectral and coherence activity during interleaved propofol/ketamine sedation mimics NREM/REM sleep activity.

Deep brain stimulation (DBS) is currently a standard procedure for advanced Parkinson's disease. Many centers employ awake physiological navigation and stimulation assessment to optimize DBS localization and outcome. To enable DBS under sedation, asleep DBS, we characterized the cortico-basal ganglia neuronal network of two nonhuman primates under propofol, ketamine, and interleaved propofol-ketamine (IPK) sedation. Further, we compared these sedation states in the healthy and Parkinsonian condition to those of healthy sleep. Ketamine increases high-frequency power and synchronization while propofol increases low-frequency power and synchronization in polysomnography and neuronal activity recordings. Thus, ketamine does not mask the low-frequency oscillations used for physiological navigation toward the basal ganglia DBS targets. The brain spectral state under ketamine and propofol mimicked rapid eye movement (REM) and Non-REM (NREM) sleep activity, respectively, and the IPK protocol resembles the NREM-REM sleep cycle. These promising results are a meaningful step toward asleep DBS with nondistorted physiological navigation.

Remote ischemic preconditioning improves tissue oxygenation in a porcine model of controlled hemorrhage without fluid resuscitation.

Remote ischemic preconditioning (RIPC) involves deliberate, brief interruptions of blood flow to increase the tolerance of distant critical organs to ischemia. This study tests the effects of limb RIPC in a porcine model of controlled hemorrhage without replacement therapy simulating an extreme field situation of delayed evacuation to definitive care. Twenty-eight pigs (47 ± 6 kg) were assigned to: (1) control, no procedure (n = 7); (2) HS = hemorrhagic shock (n = 13); and (3) RIPC + HS = remote ischemic preconditioning followed by hemorrhage (n = 8). The animals were observed for 7 h after bleeding without fluid replacement. Survival rate between animals of the RIPC + HS group and those of the HS group were similar (HS, 6 of 13[46%]-vs-RIPC + HS, 4 of 8[50%], p = 0.86 by Chi-square). Animals of the RIPC + HS group had faster recovery of mean arterial pressure and developed higher heart rates without complications. They also had less decrease in pH and bicarbonate, and the increase in lactate began later. Global oxygen delivery was higher, and tissue oxygen extraction ratio lower, in RIPC + HS animals. These improvements after RIPC in hemodynamic and metabolic status provide essential substrates for improved cellular response after hemorrhage and reduction of the likelihood of potentially catastrophic consequences of the accompanying ischemia.

Outcome of delayed primary internal fixation of distal radius fractures: a comparative study.

INTRODUCTION AND AIM: Operative fixation of distal radius fractures using fixed-angle devices has become increasingly common. Although good to excellent results have been reported in acute fractures, little is currently known regarding the fixation of healing displaced distal radius fractures that were presented late. The aim of this study was to evaluate the results of internal fixation of distal radius fractures presented late (>21 days) as compared with an acute-care control group. METHODS: Forty patients operated on for displaced distal radius fractures, presenting more than 21 days after injury (delayed treatment (DT) group), were compared with 75 age-matched controls with acute fracture repair (≤21 days). The same surgical approach was used in both groups, together with dorsal soft-tissue and brachioradialis release. No osteotomy was required. Direct and indirect reduction aids were used. A fixed-angle device (DVR; Biomet Inc., Warsaw, IN, USA) was used in both groups. Mean follow-up was 3.4 years. Quick DASH (Disabilities of the Arm, Shoulder and Hand) and Short Form 12 scores were used to evaluate outcome, as well as radiographic analysis for Arbeitsgemeinschaft für Osteosynthesefragen(AO)/Orthopaedic Trauma Association(OTA) classification, volar tilt, radial inclination and radial length. RESULTS: Average age was 53 years in both groups and male to female (M/F) ratio was similar in the study groups. Mean time to surgery was 30 days in the DT group and 8 days in the control group. There were significantly more type C (91.5% vs. 67.5%) fractures in the control group. The average quick DASH score was 27.1 in the DT group as compared with 6.3 in the control group (p<0.03); however, when controlling for two outlier cases with complications (hardware irritation and a sensory neuropathy) there was no significant difference. Volar tilt, radial inclination and length were similar in both groups and were within normal anatomical values. CONCLUSIONS: Delayed primary operative fixation of displaced unstable distal radial fractures is a viable option for cases that were presented late, with predictable, favourable results. Neither extensile approaches nor formal osteotomies are required.

Immune system augmentation by glatiramer acetate of peripheral nerve regeneration-crush versus transection models of rat sciatic nerve.

Immune system augmentation, using the antigen glatiramer acetate (GA), which is known to affect cellular immunity, has been shown to have a positive effect on peripheral nerve regeneration. We aimed to compare the effect of GA on the regeneration of crushed versus transected nerves. Wild-type rats underwent crush or transection and repair of the sciatic nerve. They were examined 3 weeks postinjury histologically (axon count) and functionally (tibialis anterior muscle weight and footprint analysis). GA was found to augment regeneration both histologically and functionally. In the transected nerve, a significant increase in axon count distal to the injury site was seen in the GA group versus control. A similar yet statistically insignificant trend was found in the crushed nerve. Improvement was found in the footprint analysis between the GA and control groups in both crush and transected nerve groups. We found improvement in the footprint analysis in the crush versus transection group. GA was found to improve the regeneration of the peripheral nerve. Histologically, this was more pronounced in the transection injury. The discrepancy between the different functional measures examined may be explained by the distance of the reinnervated muscles evaluated from the injury site.