[Obturator nerve block]. / Blockade des Nervus obturatorius - Techniken und Indikationen.

Obturator nerve block is commonly used for transurethral resections of the bladder in order to inhibit reflectory adductor muscle reaction during electrocoagulation and to reduce the risk of bladder wall perforation during transurethral surgery. Furthermore, obturator block is used to complete regional blocks for major knee surgery in addition to femoral and sciatic nerve blocks. Continuous techniques are sometimes used to treat chronic pain problems such as adductor spasm. During a so called "3 in 1" block (femoral nerve block) the obturator nerve will only be anaesthetized in 0-62% of the patients. Therefore, a specific approach to the obturator nerve is deemed appropriate. In addition, an accessory branch of the obturator nerve will accompany the femoral nerve in 10-30% of the patients. The classical approach uses the tuberculum pubicum as an anatomical landmark, inserting the needle approximately 1.5cm lateral and caudal until bone contact is established. After laterocaudal redirection the canalis obturatorius is reached and the local anaesthetic is injected. The alternative approach is more often used: At the proximal tendon insertion of the adductor longus muscle the needle is introduced and advanced towards the anterior superior iliac spine. For both approaches a nerve stimulator is used and 15-20ml of local anaesthetic solution are injected.

Basic life support with four different compression/ventilation ratios in a pig model: the need for ventilation.

BACKGROUND: During cardiac arrest the paramount goal of basic life support (BLS) is the oxygenation of vital organs. Current recommendations are to combine chest compressions with ventilation in a fixed ratio of 30:2; however the optimum compression/ventilation ratio is still debatable. In our study we compared four different compression/ventilation ratios and documented their effects on the return of spontaneous circulation (ROSC), gas exchange, cerebral tissue oxygenation and haemodynamics in a pig model. METHODS: Study was performed on 32 pigs under general anaesthesia with endotracheal intubation. Arterial and central venous lines were inserted. For continuous cerebral tissue oxygenation a Licox PtiO(2) probe was implanted. After 3 min of cardiac arrest (ventricular fibrillation) animals were randomized to a compression/ventilation-ratio 30:2, 100:5, 100:2 or compressions-only. Subsequently 10 min BLS, Advanced Life Support (ALS) was performed (100%O(2), 3 defibrillations, 1mg adrenaline i.v.). Data were analyzed with 2-factorial ANOVA. RESULTS: ROSC was achieved in 4/8 (30:2), 5/8 (100:5), 2/8 (100:2) and 0/8 (compr-only) pigs. During BLS, PaCO(2) increased to 55 mm Hg (30:2), 68 mm Hg (100:5; p=0.0001), 66 mm Hg (100:2; p=0.002) and 72 mm Hg (compr-only; p<0.0001). PaO(2) decreased to 58 mmg (30:2), 40 mm Hg (100:5; p=0.15), 43 mm Hg (100:2; p=0.04) and 26 mm Hg (compr-only; p<0.0001). PtiO(2) baseline values were 12.7, 12.0, 11.1 and 10.0 mm Hg and decreased to 8.1 mm Hg (30:2), 4.1 mm Hg (100:5; p=0.08), 4.3 mm Hg (100:2; p=0.04), and 4.5 mm Hg (compr-only; p=0.69). CONCLUSIONS: During BLS, a compression/ventilation-ratio of 100:5 seems to be equivalent to 30:2, while ratios of 100:2 or compressions-only detoriate peripheral arterial oxygenation and reduce the chance for ROSC.

Use of ProSeal laryngeal mask airway in 2114 adult patients: a prospective study.

BACKGROUND: There have been numerous studies published on the ProSeal laryngeal mask airway (PLMA). However, few have investigated its utility in a large practice setting. We sought to gather comprehensive data about the characteristics, efficacy, and safety of its use by a representative group of anesthesiologists working at a teaching center. METHODS: Information was collected on a standardized data collection form. Clinical information obtained included user characteristics, patient characteristics, type and duration of operation, details of airway management and anesthetic technique, details of adverse events, and postoperative status of the patient. RESULTS: Use of the PLMA was documented in 2114 patients by 81 anesthesiologists (57% trainee, 43% staff grade). The insertion success rate was 99% within a maximum of 3 attempts. Mean airway leak pressure was 28 (11-40) cm H(2)O. In 3.2% of cases, the PLMA was abandoned in favor of the endotracheal tube. Ventilation was controlled in 98%. Clinically "relevant" adverse events were recorded in 3.3% of all cases, of which 0.6% were classified as "serious." No long-term adverse sequelae resulted. No signs of aspiration were found in 12 patients with apparent regurgitation of gastric fluid through the drain tube of the PLMA. Five cases of difficult ventilation and 16 cases of difficult endotracheal intubation were successfully managed by the use of the PLMA. CONCLUSION: This study demonstrates that airway management using the PLMA is safe and effective in a general practice setting. The results support the assumption that a correctly positioned PLMA can protect from pulmonary aspiration of regurgitate gastric fluid. The data also support use of the PLMA for the management of the difficult airway.