Regional nerve block for total knee arthroplasty

Femoral and sciatic nerve blocks have been used occasionally for unilateral total knee arthroplasty (TKA). In order to evaluate the effectiveness of this technique, combined femoral 3-in-1 and sciatic nerve blocks were performed in 20 cases of TKA, by the same surgeon. This surgeon also performed unilateral TKA under spinal anesthesia in another 20 cases. The anesthetic effectiveness of the two types of anesthesia was compared in terms of the time needed to complete the surgery, amount of intraoperative blood loss, and time interval until the first dose of analgesic. The results showed that the two types of anesthesia had comparable anesthetic effects. Ten of the 20 patients who had spinal anesthesia complained of postoperative urinary retention, while none of those who had nerve block had this complaint. Neither group experienced postpunctural headache, neurovascular damage, or drug-over-dose toxicity. We conclude that combined femoral 3-in-1 and sciatic nerve block is an effective anesthetic alternative for unilateral TKA.     

Polypharmacy and the risk of drug-drug interactions among Danish elderly. A prescription database study

BACKGROUND AND OBJECTIVES: Interscalene block can be chosen for complete anesthesia for shoulder surgery. Phrenic nerve block occurs with almost all interscalene blocks, but is well tolerated in most patients. This may not be the case in selected geriatric patients. METHODS: The patient is a 90-year-old female with osteoarthritis of the left shoulder scheduled for total shoulder anthroplasty. Past medical history revealed hypertension, mild mitral valve insufficiency, and a remote episode of congestive heart failure. She underwent interscalene block with 40 mL of 1.4% mepivacaine, 1:200,000 epinephrine freshly added, alkalinized with sodium bicarbonate. RESULTS: The onset of the block was rapid and complete. The patient had minimal intravenous sedation (0.5 mg midazolam) and was resting comfortably with a respiratory rate of 12-14 breaths/min. Approximately 5 minutes after the injection of local anesthetic, the patient was noted to be alert, cyanotic, denying dyspnea, with an oxygen saturation of 75-85%. A chest radiograph revealed elevation of the ipsilateral hemidiaphragm and no pneumothorax or other pathology. Despite supplemental oxygen by face mask, desaturation persisted and general anesthesia was induced. On emergence from anesthesia, the patient had a complete interscalene block. Repeat chest radiograph after resolution of the block revealed return of hemidiaphragm position and no other pathology. The patient was extubated in the recovery room without difficulty. Following extubation the patient demonstrated stable respirations and normal oxyhemoglobin saturation. CONCLUSIONS: Ipsilateral phrenic nerve paralysis caused significant respiratory compromise in an elderly patient without known significant pulmonary disease.     

Primary non-Hodgkin''s lymphoma of the larynx in an AIDS patient

BACKGROUND AND OBJECTIVES: Interscalene brachial plexus block is a useful technique to provide anesthesia and analgesia for the shoulder and proximal upper extremity. The initial needle direction at the interscalene groove has been described as being "perpendicular to the skin in every plane" (1). A cross-sectional (axial) approach may offer a more easily conceptualized directed needle placement. The purpose of this study is to define the cross-sectional anatomy and idealized needle angles important to interscalene brachial plexus block. METHODS: Following IRB approval, 50 patients were studied. Cross-sectional volume coil T1-weighted magnetic resonance images (MRI) were obtained from 50 patients undergoing cervical region imaging for other reasons. At the interscalene groove, a simulated needle path to contact the ventral rami or trunks of the brachial plexus was approximated at the level of C6 or C6-C7 interspace. The angle of this needle path intersecting the sagittal plane was recorded for each patient. RESULTS: The mean angle of the simulated needle path relative to sagittal plane was determined to be 61.1 +/- 6.1 degrees (range, 50-78 degrees). In 13 of 50 (26%) MRI scans, the cervical nerve roots were not visualized at the level of C6 and were measured at the C6-C7 level. CONCLUSIONS: These findings suggest initial needle placement at the interscalene groove should be angled less perpendicularly relative to the sagittal plane than is often observed. A cross-sectional approach enables more practical visualization of initial needle placement. A more accurate initial needle placement may minimize the number of needle passes necessary to contact the nerve roots, thereby more efficiently obtaining a successful block.     

Lower limb blocks in children

Conduction blocks have important advantage over spinal blocks for unilateral low extremity surgery in children. The complexity of innervation compared with upper limb is more apparent than real and a good understanding of fascial diffusion spaces is as essential as it is of neural pathways. Useful techniques can be classified into two groups, proximal blocks and distal blocks. Beside emergency situations, proximal blocks are usually performed under light general anaesthesia, with the aid of a neurostimulation. The most used proximal blocks are the femoral block, the sciatic nerve block and to a lesser degree the lumbar plexus direct blockade. Distal blocks can complete a non quite satisfactory proximal block, or be effected so as to obtain analgesia in a limited area (in a cooperative vigil patient). Some of these consist of several anaesthetic subcutaneous infiltrations for which no costly material nor special dexterity are required. A judicious choice among the main available techniques allows an excellent analgesia with a very low cost and almost no risks.     

Intraneural lidocaine uptake compared with analgesic differences between pregnant and nonpregnant rats

BACKGROUND AND OBJECTIVES: Pregnant patients need less local anesthetic in order to obtain the same quality of functional block as nonpregnant patients. Our goal was to demonstrate a similarly increased functional susceptibility to local anesthetics in the awake pregnant rat during peripheral nerve block and to investigate the pharmacokinetic and/or pharmacodynamic mechanisms responsible for this phenomenon. METHODS: Radiolabeled lidocaine uptake was determined in vivo during sciatic nerve block with 0.1 ml of 1% lidocaine in the nerves of nine pregnant and five nonpregnant female rats and six male rats at the return of deep pain sensation, assessed by withdrawal of the hindlimb from a brief squeeze of a digit with serrated forceps. During recovery from complete functional block, the time at which deep pain returned and the amount of lidocaine in the nerve at that time were compared among the three groups of rats. Lidocaine content was also determined in vitro after exposure of ensheathed sciatic nerves from pregnant and nonpregnant rats to a 0.2% lidocaine bath for specified times. RESULTS: Full block of function developed in all groups within 6 minutes of the lidocaine injection and lasted significantly longer in pregnant rats than in nonpregnant and male rats (49.0 +/- 3.3 vs 34.0 +/- 3.1 and 32.0 +/- 1.3 minutes mean +/- SEMI, respectively. At the time of deep pain return, the intraneural lidocaine content of pregnant rats was significantly lower than that of nonpregnant and male rats (2.2 +/- 0.25 vs 3.9 +/- 0.7 and 3.7 +/- 0.6 nmoles/mg of wet nerve, respectively). No difference in lidocaine uptake kinetics between P and NP nerves was observed in vitro. CONCLUSIONS: Block of peripheral neural function is prolonged in pregnant rats, and lidocaine content in the nerve is lower at a specific stage of neural block. These results are consistent with a pharmacodynamic mechanism for increased susceptibility to lidocaine neural block during pregnancy.     

Release of somatostatin and its role in the mediation of the anti-inflammatory effect induced by antidromic stimulation of sensory fibres of rat sciatic nerve

1. The effect of antidromic stimulation of the sensory fibres of the sciatic nerve on inflammatory plasma extravasation in various tissues and on cutaneous vasodilatation elicited in distant parts of the body was investigated in rats pretreated with guanethidine (8 mg kg(-1), i.p.) and pipecuronium (200 microg kg(-1), i.v.). 2. Antidromic sciatic nerve stimulation with C-fibre strength (20 V, 0.5 ms) at 5 Hz for 5 min elicited neurogenic inflammation in the innervated area and inhibited by 50.3 +/- 4.67% the development of a subsequent plasma extravasation in response to similar stimulation of the contralateral sciatic nerve. Stimulation at 0.5 Hz for 1 h also evoked local plasma extravasation and inhibited the carrageenin-induced (1%, 100 microl s.c.) cutaneous inflammation by 38.5 +/- 10.0% in the contralateral paw. Excitation at 0.1 Hz for 4 h elicited no local plasma extravasation in the stimulated hindleg but still reduced the carrageenin-induced oedema by 52.1 +/- 9.7% in the paw on the contralateral side. 3. Plasma extravasation in the knee joint in response to carrageenin (2%, 200 microl intra-articular injection) was diminished by 46.1 +/- 12.69% and 40.9 +/- 4.93% when the sciatic nerve was stimulated in the contralateral leg at 0.5 Hz for 1 h or 0.1 Hz for 4 h, respectively. 4. Stimulation of the peripheral stump of the left vagal nerve (20 V, 1 ms, 8 Hz, 10 min) elicited plasma extravasation in the trachea, oesophagus and mediastinal connective tissue in rats pretreated with atropine (2 mg kg(-1), i.v.), guanethidine (8 mg kg(-1), i.p.) and pipecuronium (200 microg kg(-1), i.v.). These responses were inhibited by 37.8 +/- 5.1%, 49.7 +/- 9.9% and 37.6 +/- 4.2%, respectively by antidromic sciatic nerve excitation (5 Hz, 5 min) applied 5 min earlier. 5. Pretreatment with polyclonal somatostatin antiserum (0.5 ml/rat, i.v.) or the selective somatostatin depleting agent cysteamine (280 mg kg(-1), s.c.) prevented the anti-inflammatory effect of sciatic nerve stimulation (5 Hz, 5 min) on a subsequent neurogenic plasma extravasation of the contralateral paw skin. The inhibitory effect of antidromic sciatic nerve excitation on plasma extravasation in response to vagal nerve stimulation was also prevented by somatostatin antiserum pretreatment. 6. Cutaneous blood flow assessment by laser Doppler flowmetry indicated that antidromic vasodilatation induced by sciatic nerve stimulation was not inhibited by excitation of the sciatic nerve of the contralateral leg (1 Hz, 30 min) or by somatostatin (10 microg/rat, i.v.) injection. 7. Plasma levels of somatostatin increased more than 4 fold after stimulation of both sciatic nerves (5 Hz, 5 min) but the stimulus-evoked increase was not observed in cysteamine (280 mg kg(-1), s.c.) pretreated rats. 8. These results suggest that somatostatin released from the activated sensory nerve terminals mediates the systemic anti-inflammatory effect evoked by stimulating the peripheral stump of the sciatic nerve.     

Regional anesthesia techniques for pain control in the intensive care unit

The judicious use of regional anesthesia in the intensive care unit should improve patient comfort. Techniques covered include intercostal nerve blocks, interpleural blocks, paravertebral blocks, brachial plexus blocks, and femoral nerve blocks. Rational patient selection for each technique mentioned is also discussed.     

Suprascapular nerve block for postoperative pain relief in arthroscopic shoulder surgery: a new modality?

Arthroscopic shoulder surgery has a 45% incidence of severe postoperative pain. Opiates and interscalene nerve blocks have a high incidence of side effects, and intraarticular local anesthetic has been shown to be ineffective when used for postoperative pain relief. The suprascapular nerve supplies 70% of the sensory nerve supply to the shoulder joint, and local anesthetic block of this nerve is effective in certain shoulder pain disorders. To determine the efficacy of a suprascapular nerve block, subcutaneous saline was compared with a suprascapular nerve block using 10mL of 0.5% bupivacaine with 1:200,000 epinephrine before general anesthesia was induced. In the immediate postoperative period, a 51% reduction in demand and a 31% reduction in consumption of morphine delivered by a patient-controlled analgesic system was demonstrated. There was more than fivefold reduction in the incidence of nausea, as well as reduced visual analog and verbal pain scores for patients who received a suprascapular nerve block. The duration of hospital stay was reduced by 24% in the suprascapular nerve block group. A 24-h phone call interview revealed a 40% reduction in analgesic consumption and a reduction in verbal pain scores at rest and on abduction. There were no complications from the suprascapular nerve block. This study demonstrates that a suprascapular nerve block for pain relief in arthroscopic shoulder surgery is an effective and safe modality of postoperative pain relief.     

Sciatic nerve palsy following childbirth

Two cases are reported of sciatic nerve palsy after delivery by Caesarean section in primigravidae. One mother was slender and had an emergency Caesarean section for failure to progress with a breech presentation. Epidural analgesia during labour was extended for operative delivery. The other mother was obese, mildly hypertensive, had a large baby with a high head and was delivered by elective Caesarean section under epidural anaesthesia. She experienced severe intrapartum hypotension. Both patients suffered right sided sciatic nerve palsy. The aetiologies of obstetric palsies and those following regional block are reviewed and the importance of careful diagnosis and of avoiding peripheral nerve compression during regional block are emphasised.     

Acute stretching of peripheral nerves inhibits retrograde axonal transport

The conjugation of horseradish peroxidase with wheat germ agglutinin was used to identify the effect on retrograde axonal transport of stretching the rat sciatic nerve indirectly by 10% and 20% femoral lengthening with a unilateral external fixator. To investigate the relationship between retrograde axonal transport and blood flow in the stretched nerve, nerve blood flow in the sciatic nerve was measured by a hydrogen washout technique. At 11% strain (20% femoral lengthening), the numbers of horseradish peroxidase-labelled motor neuron cells and nerve blood flow had decreased by 43% and 50%, respectively. Histological examination demonstrated ischaemic changes, but not mechanical damage. However, at 6% strain (10% femoral lengthening) there were no significant abnormalities. These findings suggest that the inhibition of retrograde axonal transport can be induced by acute stretching of the peripheral nerve and that circulatory disturbance is the main cause of the inhibition of retrograde axonal transport at the low strain.     

Benchmarking the perioperative process: III. Effects of regional anesthesia clinical pathway techniques on process efficiency and recovery profiles in ambulatory orthopedic surgery

STUDY OBJECTIVES: (1) To incorporate regional anesthesia options for common outpatient orthopedic surgery into clinical pathways; (2) to use the clinical pathway format and the Procedural Times Glossary published by the Association of Anesthesia Clinical Directors (AACD) as management tools to measure postoperative same-day surgery processes and discharge outcomes; and (3) to determine the effects of general, regional, and combined general-regional anesthesia on these processes and outcomes. DESIGN: Hospital database and patient chart review of consecutive patients undergoing anterior cruciate ligament reconstruction (ACLR) during academic years (AY) 1995-1996 and 1996-1997. Patient data from AY 1995-1996, during which no intraoperative anesthesia clinical pathway existed, served as historical controls. Data from AY 1996-1997, during which intraoperative anesthesia clinical pathways were used, served as the treatment group. SETTING: Ambulatory surgery center in a teaching hospital. MEASUREMENTS AND MAIN RESULTS: The records of 503 ASA physical status I and II patients were reviewed. 1996-1997 patients selected general anesthesia (+/- femoral nerve block) or epidural anesthesia, after which the remainder of the perioperative anesthesia process was standardized with respect to the drugs and equipment used. 1995-1996 patients did not necessarily have a choice in anesthesia technique and did not have a standardized perioperative anesthetic course with respect to specific drugs and supplies. Intervals described in the AACD Procedural Times Glossary, anesthesia drug and supply costs, and patient outcome variables (postoperative nursing interventions required and unexpected admissions), as influenced by anesthesia technique used, were measured. Combined general-regional anesthesia care for ACLR in 1996-1997, when compared with general anesthesia alone, led to increased pharmacy and materials costs and increased turnover time. However, patients with the combined technique showed improved recovery profiles and lower unexpected admission rates, and they required fewer nursing interventions for common postoperative symptoms. Patients receiving epidural anesthesia showed discharge outcomes similar to those patients receiving general anesthesia with femoral nerve block. Postanesthesia care unit bypass (fast-tracking) was more likely in clinical pathway regional anesthesia patients, when compared with the clinical pathway general anesthesia used. CONCLUSIONS: Clinical pathway regional anesthesia care for outpatient orthopedics may have a significant role in simultaneously containing costs and improving both process efficiency and patient outcomes.     

Alkalinization of lidocaine does not hasten the onset of axillary brachial plexus block

We assessed the onset of sensory and motor blockade as well as the distribution of sensory blockade after axillary brachial plexus block with 1.5% lidocaine hydrochloride 1:200,000 epinephrine with and without sodium bicarbonate in 38 patients. The onset of analgesia and anesthesia was recorded over the distributions of the median, ulnar, radial, and medial cutaneous nerves of the forearm, medial cutaneous and lateral cutaneous nerves of the arm, and musculocutaneous nerve. The onset of motor blockade of elbow and wrist movements was also recorded. Data were analyzed by using survival techniques and compared by using log rank tests. Only the onset of analgesia in the medial cutaneous nerves of the arm and forearm, and the onset of anesthesia in the medial cutaneous nerve of the arm were significantly faster (P < 0.05) with alkalinization of lidocaine. Our study showed that alkalinization of lidocaine does not significantly hasten block onset in most terminal nerve distributions. IMPLICATIONS: We examined whether alkalinizing a local anesthetic would quicken the onset of a regional upper limb nerve blockade. We found that alkalinization of lidocaine did not offer a significant clinical advantage in axillary brachial plexus blockade.     

Current local anesthetics in segmental nerve blocks

The evolution of central segmental blockades was studied in 133 patients by using epidural and spinal anesthesias. The efficiencies of 2% Ultracaine (Hoechst) and 2% Lidocaine (Egis) solutions used for epidural anesthesia and 5% Ultracaine (Hoechst) and 0.75% Bupivacaine (Astra) hyperbaric solutions were evaluated. Central segmental blockade induced by Ultracaine was found to be similar to Lidocaine and Bupivacaine in clinical parameters. At epidural blockade, the latent period was identical for the two agents and the duration of analgesia caused by Ultracaine was 20 minutes longer than that with Lidocaine, the consumption of the former being 20% less. At spinal anesthesia, there were no great differences in the depth and duration of conduction block, but with 5% Ultracaine, the analgesic zone was large (13.2 +/- 1.0 and 15.1 +/- 0.6 segments, p < 0.05). No differences were found in the magnitude of hemodynamic changes both with various anesthetics and different types of segmental blockades. The findings make it possible to regard Ultracaine as an drug that has some advantage over Lidocaine for prolonged epidural anesthesia and similar to the latter in pharmacological characteristics. Ultracaine may be regarded as alternative to Bupivacaine for spinal anesthesia.     

T2 relaxation of peripheral nerve measured in vivo

It is demonstrated that multi-exponential transverse (T2) relaxation components can be estimated from multi-echo images of peripheral nerve. Three T2-relaxation components with T2 values +/- standard deviations (populations +/- standard deviations) of 19 +/- 7 ms (26 +/- 9%), 63 +/- 31 ms (29 +/- 11%) and 241 +/- 24 ms (45 +/- 7%) have been identified in vivo in the sciatic nerve of the amphibian Xenopus laevis. The longer-lived component, not identified previously in vivo, provides a significant contrast-to-noise ratio (CNR) between nerve and muscle in the latter-echo images. It is shown that the CNR can be further improved by the averaging of selected images from the multi-echo set.     

Comparison of the clinical efficacy of three perivascular techniques for axillary brachial plexus block

BACKGROUND AND OBJECTIVES: This study compared the efficacy of three perivascular techniques of axillary block. METHODS: In group 1, all of the local anesthetic was injected after advancing the needle through the axillary artery (back of artery, n = 20); in group 2, after withdrawing slightly from the artery (front of artery, n = 20); and in group 3, half of the anesthetic was injected after advancing through and half after withdrawing from the axillary artery (half and half, n = 20). The local anesthetic used for the axillary block was 50 ml of 1.5% mepivacaine with epinephrine 1:200,000. RESULTS: The groups did not differ significantly in the incidence of analgesia or anesthesia expected in the median nerve distribution, where there was a significantly lower incidence of anesthesia in the back of the artery group. This group also had a slower onset of anesthesia for the median and the medial antebrachial cutaneous nerves. CONCLUSIONS: There was no significant difference in the number of patients requiring supplementation, with five patients in the back group (25%), three patients in the front group (15%), and one patient in the half and half group (5%) requiring supplementation for the surgical procedure.     

Regional anesthetic procedures in pediatric anesthesia

Regional anaesthetic procedures are not popular in paediatric anaesthesia in many institutions. However, regional anaesthesia is gaining ground, especially in a "new" concept of balanced paediatric anaesthesia. The decisive argument for the use of regional anaesthesia is the prolongation of pain relief further into the postoperative phase. The minimal haemodynamic and respiratory side effects during epidural and spinal anaesthesia, the reduced narcotic requirement and the potential early mobilisation all speak in favour of practical application of these techniques. Specially adapted needles and catheters have reduced the technical limitations. The use of nerve stimulators has optimize the accuracy of needle and catheter positioning. The use of a nerve stimulator is therefore highly recommended for peripheral nerve blocks in children. On the other hand, the use of regional anaesthesia in children has potential disadvantages, which should be considered. Special knowledge and continuous training are required. Many techniques are time consuming and personnel intensive, at least temporarily, and the combination of general and regional anesthesia exposes the child to the potential risk inherent in both procedures. The aim of this paper is to discuss procedures which have gained favour in paediatric regional anaesthesia during the past few years. These include caudal, epidural and spinal anaesthesia, especially for infants with high narcotic risk, as well as fascia iliaca compartment blocks for lower extremity analgesia and penile blocks. Many peripheral nerve blocks require special experience and therefore are not discussed here, but they are used routinely by specialists in all age groups. Good anatomic and pharmacologic knowledge should be a prerequisite for all physicians who use regional anaesthetic procedures. Continuous training and critical analysis are needed for good results. Only then can such methods be introduced into routine paediatric anaesthetic practice.     

Identification of a histidine residue essential for enzymatic activity of group B streptococcal hyaluronate lyase

Parascalene block is a technique of blocking the brachial plexus at the lateral border of the anterior scalene muscle superior to the clavicle. The objective of this study was to define the position of the needle in parascalene block with relationship to the brachial plexus and the dome of the pleura, which is important in determining whether this technique minimizes the incidence of pneumothorax. In the first group, 10 patients scheduled for minor upper extremity surgery agreed to parascalene block, which was performed in the computed tomographic examination room. In the second group, 10 volunteers agreed to have markers placed at the point where a needle would be inserted for parascalene block. The computed tomographic study at the level of the needle insertion or the marker revealed that this level was superior to the dome of the pleura. The distances from the skin to the interscalene groove and the interscalene groove to the first rib at the level of the needle insertion or the marker in both groups were measured to be 17 +/- 4 mm and 15 +/- 3 mm, respectively. This study suggests that the level of the parascalene needle entry is superior to the dome of the pleura. At this level, the incidence of pneumothorax should be minimized.     

Blocking of the brachial plexus: which technique(s) should be chosen?]

Brachial plexus blocks for upper extremity surgery: what are the preferred techniques? Brachial plexus anaesthesia for all types of upper extremity surgical procedures cannot be adequately achieved with a single technique. At least, two approaches are required: above the clavicle, Winnie's interscalene brachial plexus block, using a neurostimulator, has become the standard technique for shoulder surgery. Below the clavicle, midhumerus approach is the most successful approach for elbow, fore arm and hand surgery, especially for outpatient surgery. The best approach for catheter insertion along brachial plexus nerves/trunks remain controversial. The supraclavicular approach using surface landmarks might be the best approach due to its efficacy in achieving complete anaesthesia of the upper extremity and the rarity of secondary displacement of the catheter. Whatever the selected approach(es) to brachial plexus nerves, nerve location it best achieved by neurostimulation and often multiple neurostimulation. Insulated needles are being increasingly used due to accuracy but, currently, there is no general agreement concerning the type of needle bevel to be preferred in regard to both safety and accuracy.     

Motor denervation induces altered muscle fibre type densities and atrophy in a rat model of neuropathic pain

Loose ligation of a sciatic nerve in rats (chronic constriction injury; CCI) provokes sensory, autonomic, and motor disturbances like those observed in humans with partial peripheral nerve injury. So far, it is unknown whether these motor disturbances result from (mechanical) allodynia or from damage to the motor neuron. These considerations prompted us to assess, in CCI rats, the density of motor axons in both the ligated sciatic nerve and the ipsilateral femoral nerve. To this end, we determined the number of cholinesterase positive fibres. It has been demonstrated previously that muscle fibre type density may be used as a measure of motor denervation and/or hypokinesia. Therefore, the myofibrillar ATPase reaction was employed to assess fibre type density in biopsies obtained from the lateral gastrocnemius muscle (innervated by sciatic nerve) and rectus femoris muscle (innervated by femoral nerve). We observed axonal degeneration of motor fibres within the loosely ligated sciatic nerve, both at an intermediate (day 21) and at a late stage (day 90) after nerve injury. The reduction in the number of motor nerve fibres was more pronounced distal to the site of the ligatures than proximal. A (less pronounced) reduction of motor fibres was observed in the ipsilateral (non-ligated) femoral nerve. In line with these findings, we observed altered fibre type densities in muscle tissue innervated by the ligated sciatic nerve as well as the non-ligated femoral nerve indicative of motor denervation rather than hypokinesia. The findings of this study suggest that the motor disorder induced by partial nerve injury involves degeneration of motor nerve fibres not only within the primarily affected nerve but also within adjacent large peripheral nerves. This spread outside the territory of the primarily affected nerve suggests degeneration of motor neurons at the level of the central nervous system.     

DHEA as physiological replacement therapy at menopause

BACKGROUND: We report on a case of combined sciatic nerve block and 3-in-1 block for amputation of lower limb in an ASA IV-V patient 6 days after intraoperative cardiopulmonary resuscitation following induction of general anaesthesia. CASE REPORT: A 54-year old male patient was admitted for necrosectomy of a crural ulcer due to end-stage peripheral vascular disease and non-insulin dependent diabetes mellitus. The patient also suffered from toxic cardiomyopathy. After induction for general anaesthesia the haemodynamic situation deteriorated progressively and ended up in cardiac arrest with consequent successful cardiopulmonary resuscitation. The operation was cancelled and the patient was admitted to the intensive-care unit, where he was extubated after 2 days of further haemodynamic stabilisation. Following development of a septic situation of the lower limb the patient was again admitted for amputation six days after the cardiopulmonary resuscitation. Regional anaesthesia was conducted with a combination of a sciatic nerve block via the posterior approach and a 3-in-1 block facilitated by ultrasonographic guidance. For each of the blocks we used 20 mL mepivacaine 1%. Sensory blockade was sufficient and the patient remained haemodynamic and respiratorily stable. DISCUSSION AND CONCLUSIONS: The combined sciatic and 3-in-1 block is a rarely used technique, but for haemodynamically unstable patients it is a safe method for surgery of the lower limb.