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John Silas Lundy created the Anaesthetists' Travel Club in 1929 in an effort to disseminate the most current information in the medical specialty of anesthesiology, but also to insure that this information was incorporated quickly to improve anesthesia care. Lundy's work stands as an example of commitment to professional competence.

A very successful comprehensive multimodal pain protocol is used at our institution for both primary and revision total hip arthroplasties. Two concepts are essential to the success of this protocol: 1) using multiple modalities of analgesia to address patients' pain and 2) preemptively treating pain so that patients do not need additional medication to "catch up" with the postoperative pain they are likely to experience. Peripheral nerve blocks are essential to the success of this multimodal analgesia program. Total hip arthroplasty patients receive a lumbar plexus block with an indwelling psoas or fascia iliaca catheter. Before surgery, patients are given a long-acting oral narcotic medication and a nonsteroidal anti-inflammatory drug (NSAID) to preemptively address pain. After surgery, oral medications, including acetaminophen, a NSAID and a long-acting oral narcotic, are administered on a scheduled basis. Outstanding pain control is achieved routinely without parenteral narcotics and that allows early physical therapy, early return to self-care, and earlier discharge from the hospital.

Dyke, Christopher K., Niki M. Dietz, Robert L. Lennon, David O. Warner, and Michael J. Joyner. Forearm blood flow responses to handgripping after local neuromuscular blockade. J. Appl. Physiol. 84(2): 754–758, 1998.—To test the hypothesis that acetylcholine “spillover” from motor nerves contributes significantly to skeletal muscle vasodilation during exercise, we measured the forearm blood flow responses during attempted handgripping after local paralysis of the forearm with the neuromuscular-blocking drug pipecuronium. This compound blocks postsynaptic nicotinic receptors but has no impact on acetylcholine release from motor nerves. The drug was administered selectively to one forearm by using regional intravenous drug administration techniques in five subjects. Pipecuronium reduced maximum forearm grip strength from 40.0 ± 3.2 kg before treatment to 0.0 kg after treatment. By contrast, drug administration had no effect on maximum voluntary contraction in the untreated forearm (41.3 ± 3.3 vs. 41.4 ± 2.7 kg). During 2 min of attempted maximal contraction of the paralyzed forearm, the forearm blood flow increased from only 3.4 ± 0.8 to 4.8 ± 1.2 ml ⋅ 100 ml−1 ⋅ min−1( P < 0.05). Heart rate increased from 63 ± 3 to 73 ± 8 beats/min ( P > 0.05) during attempted contraction, and only three of five subjects showed obvious increases in heart rate. Mean arterial pressure increased significantly ( P < 0.05) from 102 ± 6 to 109 ± 9 mmHg during attempted contractions. When these increases in flow are considered in the context of the marked (10-fold or greater) increases in flow seen in contracting forearm skeletal muscle, it appears that acetylcholine spillover from motor nerves has, at most, a minimal impact on the hyperemic responses to contraction in humans.

Cervical plexus blockade produces anesthesia of the neck, shoulder, and upper pectoral and occipital regions. Relevant anatomy for this blockade is described. For both deep and superficial blocks, the following topics are reviewed: clinical applications, patient position, needle redirection cues, and side effects and complications.

Three lower-extremity nerve blocks are examined in chapter 25: lateral femoral cutaneous, obturator, and saphenous. The following aspects of the procedure are reviewed for each block: clinical applications, relevant anatomy, patient position, technique (including neural localization techniques, needle insertion site, and needle redirection cues), and side effects and complications. A discussion of ultrasound guidance is included for saphenous nerve blockade.

Chapter 5 contains a basic review of terminology used to describe body planes, surface orientation, and movements. The anatomy of major nerve plexuses are also examined: brachial plexus, lumbar plexus, lumbosacral plexus. The chapter concludes with a discussion of peripheral nerve anatomy and sensory and motor innervation, including dermatomes, osteotomes, and myotomes.

Posterior lumbar plexus, or psoas compartment, block is primarily used to provide unilateral anesthesia and analgesia to the proximal aspect of the thigh and hip. The following aspects of the procedure are reviewed: clinical applications, relevant anatomy, patient position, technique (including neural localization techniques, needle insertion site, and needle redirection cues), and side effects and complications. Use of peripheral nerve catheters is also reviewed.

Most complication associated with peripheral nerve blockade fall into one of three categories: neurologic, hemorrhagic, or infectious. Most neurologic complications are attributable to mechanical trauma or local anesthetic toxicity. Patient, procedure, and anesthetic risk factors are reviewed. Hemorrhagic complications include bruising and hematoma formation. Single-injection and continuous catheter techniques are discussed. The possible role of catheters in infectious complications of nerve blockade is examined.

Chapter 6 provides a general overview of ultrasound principles and equipment. The overview begins with a description of the sound wave and its cycle, frequency, wave length, and amplitude. Next, the discussions turns to the sound wave's behavior in reaction to different tissue types, angle, and structure depth. Various types of image artifacts and their causes are also covered. Equipment review includes probe selection, image optimization, conducting gel, and probe stands.

Blockade of the femoral nerve provides surgical anesthesia and postoperative analgesia to the anterior aspect of the thigh and knee. The following aspects of the procedure are reviewed: clinical applications, relevant anatomy, patient position, technique (including neural localization techniques, needle insertion site, and needle redirection cues), and side effects and complications. A discussion of ultrasound guidance and peripheral nerve catheters completes the chapter

The Mayo Clinic Atlas of Regional Anesthesia and Ultrasound-Guided Nerve Blockade is a practical guide that provides a detailed and systematic approach to regional anesthesia of the upper and lower extremity, including ultrasound-guided regional techniques. The book provides a comprehensive overview of both traditional and ultrasound-guided techniques of brachial plexus, lumbar plexus, and lumbosacral plexus blockade. Each regional technique is clearly described and illustrated with ultrasound images accompanied by corresponding color anatomic illustrations. Specific information provided within each chapter includes clinical applications, relevant anatomy, surface anatomy, proceduralist and patient positioning, traditional and alternative approaches to the technique itself, needle insertion site, needle redirection cues, ultrasound Sonoanatomy, ultrasound-guided techniques, side effects and complications, and suggested reading. Special emphasis is given and abundantly illustrated on hand position and how to precisely grasp and manipulate the ultrasound probe and needle for each block technique. Successful regional anesthesia is predicated on a sound knowledge of anatomy and local anesthetic pharmacology - both of which are clearly presented and well-illustrated within the book. Finally, the text provides a comprehensive overview of the fundamental principles of ultrasonography, relevant Sonoanatomy of the upper and lower extremity, and the technical skills necessary to become clinically proficient at ultrasound-guided regional anesthesia.

Positioning-related injuries such as central and peripheral neuropathies, compartment syndromes, and soft-tissue injury can be reduced by considering preoperative and intraoperative factors. Preoperative considerations include normal joint range of motion, body habitus, and health status. Intraoperative considerations include compression by table attachments, duration of surgery, airway management, and use of pads and supports.

Ultrasound-guided regional anesthesia involves six steps: preparation, visualization, approximation, interrogation, deposition, and evaluation. Each step is reviewed in detail. Preparation includes patient positioning, monitor placement, draping, and equipment placement. Visualization involves scanning the anesthesia area to identify relevant anatomy. Approximation is determining how best to approach the target nerve with the needle. Interrogation involves nerve stimulation to determine correct needle placement so that deposition of the anesthetic can take place. Finally, evaluation of the effectiveness of the block allows for rescue options if needed. Clinical pearls and common errors and pitfalls related to ultrasound-guided regional anesthesia are also included.

Ultrasound-guided regional anesthesia is the practice of applied anatomy. A detailed knowledge of neuroanatomy and the relationships of nerves to other structures is critical to successfully perform ultrasound-based procedures. In addition to anatomical knowledge, a comprehensive understanding of ultrasound equipment, probe selection, image optimization, and scanning technique is also essential to the proceduralist. Each of these factors is reviewed.

Chapter 2 reviews the mechanism of action for local anesthetics. Clinical features such as potency, onset of action, duration, and dose are discussed. Drug metabolism, toxicity (local and systemic), and its treatment are included. The chapter concludes with additional information on adjuvant medications (eg, epinephrine, clonidine) used to extend or enhance the clinical effects of local anesthetics.

Fascia iliaca blockade is used to provide postoperative analgesia in children and adults undergoing proximal lower extremity procedures. The following aspects of the procedure are reviewed: clinical applications, relevant anatomy, patient position, technique (including neural localization techniques, needle insertion site, and needle redirection cues), and side effects and complications. Ultrasound guidance and use of continuous nerve catheters is also discussed.

Sciatic nerve blockade is performed to achieve anesthesia and analgesia of the distal lower extremity, including the anterior and posterolateral leg, ankle, and foot. The following aspects of the procedure are reviewed: clinical applications, relevant anatomy, patient position, technique (including neural localization techniques, needle insertion site, and needle redirection cues), and side effects and complications. Use of ultrasound guidance is also discussed.

Peripheral nerve catheters are typically advanced a substantial distance into a perineural sheath, theoretically increasing the risk of catheter knotting and kinking. In this case report, we describe successful removal of a knotted fascia iliaca catheter and discuss principles of nonsurgical catheter extraction. A 64-yr-old woman with bilateral coxarthrosis presented for total hip arthroplasty under combined general/regional anesthesia. A 20-gauge fascia iliaca catheter was inserted before surgery by using a loss-of-resistance "double pop" technique. The catheter was uneventfully advanced 10 cm past the needle tip. After injection of 30 mL of 0.5% bupivacaine with 1:200,000 epinephrine and 100 microg of clonidine, general anesthesia was induced. An infusion of 0.1% bupivacaine at 20 mL/h was initiated in the recovery room for postoperative analgesia. Approximately 48 h later, resistance was encountered during catheter removal. Catheter extraction was attempted by altering patient positioning, including the supine position during which the catheter placement had occurred. Successful catheter removal was achieved by decreasing tension on the fascia lata and fascia iliaca through flexion of the hip joint and by applying firm, steady traction. The catheter was removed intact with a knot approximately 2 cm from the distal tip. We conclude that the principles for removal of entrapped peripheral catheters are not well known and may differ from those for neuraxial catheters. Patient positioning to minimize pressure and tension on the perineural soft tissues may facilitate catheter removal.

The design and application of a closed-loop controller for the infusion of the muscle relaxant atracurium are described. The controller uses a processed electromyography system for the feedback signal and a new control algorithm, for which a flowchart is given. Initial clinical testing in the operating room demonstrated excellent control characteristics. The algorithm settled within 15 min with very little variation in the state of relaxation. Each person had his or her own settling point, but this was always within 7-12% of control, which produced acceptable clinical relaxation. >

UNLABELLED Doxacurium's clearance (C1) is markedly decreased in patients with renal failure undergoing kidney transplantation. However, no studies have determined the influence of renal function (as assessed by creatinine clearance [CrCl]) on its pharmacokinetics in patients without renal failure. We studied 53 patients aged 19-59 yr. During N2O/isoflurane anesthesia, doxacurium was infused over 10 min, plasma was sampled for up to 6 h, and twitch tension was measured. A three-compartment model was fit to plasma concentration data and an effect compartment model to twitch data. Mixed-effects modeling was used to determine the influence of covariates, including CrC1, on doxacurium's pharmacokinetic/pharmacodynamic parameters. Obesity decreased both doxacurium's Cl (1.1% per percent above ideal body weight [IBW]) and its neuromuscular junction sensitivity (0.4% per percent above IBW). Cl increased 0.6% per mL/min increase in CrCl. In addition, the rate constant for equilibration between plasma concentration and effect decreased 46% per 1% increase in isoflurane, central compartment volume decreased 86% per 1% increase in isoflurane concentration, and slow distributional Cl decreased 69% per mg/ 100 mL increase in serum albumin. Simulations showed that the latter two covariates influence the time course of bolus doxacurium administration minimally. Both obesity and renal dysfunction prolong doxacurium's recovery markedly. When dosing is based on IBW, effects of CrCl on neuromuscular recovery are smaller compared with dosing based on actual weight. Therefore, obese patients should be dosed based on IBW. No further dosage adjustment is necessary for patients with renal dysfunction; however, recovery will take longer in patients with moderate-to-severe renal dysfunction. IMPLICATIONS We examined the factors influencing doxacurium's pharmacokinetic and pharmacodynamic characteristics. Both creatinine clearance and obesity significantly influence its time course. The effect of obesity is minimized if patients are dosed based on ideal body weight.

The primary objective of this study was a blinded, randomized comparison of the recommended intubating dose of atracurium (0.5 mg·kg−1) with an approximately equipotent dose of cisatracurium (0.1 mg·kg−1) during N20/02/propofol/ fentanyl anaesthesia. Eighty ASA physical status 1 or 2 patients, 18–70 yr of age, within 30% of ideal body weight, scheduled for elective low to moderate risk, surgical procedures were studied. Adductor pollicis evoked twitch responses were measured with a Grass FT 10 force displacement transducer (Grass Instruments, Quincy, MA) and continuously recorded on a Gould multichannel polygraph (Gould Instrument Systems, Cleveland, OH) after induction of anaesthesia. Increasing the initial dose of cisatracurium (from 0.1 to 0.15 and 0.2 mg·kg−1, decreased mean time of onset (from 4.6 to 3.4 and 2.8 min, respectively), and increased mean time of clinically effective duration (45 to 55 and 61 min, respectively). Recovery to a T4:T1 ratio of 0.7 occurred approximately seven minutes following administration of the reversal agent neostigmine for all treatment groups. Intubation conditions were good or excellent in over 90% of patients in all treatment groups (two minutes after approximately 2 x ED95 doses of cisatracurium or atracurium and 1.5 minutes after 3 × and 4 × ED95 doses of cisatracurium). The intubation results reported in this study together with the combination of predictable recovery from neuromuscular block and apparent haemodynamic stability make cisatracurium a potentially useful muscle relaxant in clinical practice.

A microcomputer-controlled closed-loop infusion system (MCCLIS) has been developed that provides stable intraoperative levels of partial neuromuscular blockade. Complete neuromuscular blockade interferes with intraoperative motor-evoked potential (MEP) monitoring used for patients undergoing surgical procedures that place them at risk for spinal cord ischemia. Nine patients were studied during which the MCCLIS maintained stable levels of partial neuromuscular blockade and allowed transcranial magnetic motor-evoked potential (TcM-MEP) monitoring during thoracoabdominal aortic aneurysmectomy. The use of TcM-MEP for monitoring intraoperative spinal cord function was balanced against surgical considerations for muscle relaxation with 80% to 90% neuromuscular blockade fulfilling each requirement. Intraoperative adjustment of partial neuromuscular blockade to facilitate TcM-MEP monitoring was also possible with the MCCLIS. The MCCLIS should allow for further investigation into the sensitivity, specificity, and predictability of TcM-MEP monitoring for any patient at risk for intraoperative spinal cord ischemia including those undergoing thoracoabdominal aortic aneurysmectomy.

Bone cement implantation syndrome is characterized by hypotension, hypoxemia, cardiac arrhythmias, cardiac arrest, or any combination of these complications. It may result from venous embolization that occurs in conjunction with intramedullary hypertension in the femur during insertion of the prosthesis in patients undergoing cemented total hip arthroplasty (THA). Intramedullary hypertension does not occur in patients undergoing noncemented THA. In this study, we sought to compare embolization between patients undergoing cemented and noncemented THA and to determine whether this state resulted in cardiorespiratory deterioration. In this prospective investigation of 35 patients undergoing elective THA, we used transesophageal echocardiography and invasive hemodynamic monitoring, and in 12 of them, we monitored distribution of pulmonary ventilation and perfusion intraoperatively. Embolization was significantly greater after insertion of the prosthesis in patients undergoing cemented than in those undergoing noncemented THA. Cemented THA was also associated with decreased cardiac output and increased pulmonary artery pressure and pulmonary vascular resistance. Increases in ventilation-perfusion mismatching, however, could not be demonstrated 30 minutes after insertion of the femoral prosthesis. Intraoperative monitoring for embolism may help physicians assess patients in whom cardiorespiratory function deteriorates during THA.

Thirty adult surgical patients admitted to the recovery room with an oral temperature less than or equal to 35.0 degrees C were randomized into two groups. Group 1 patients were covered with cotton blankets warmed to 37.0 degrees C, and group 2 patients were treated with a forced-air warming system. Mean oral temperature on admission to the recovery room was the same in both groups (34.3 degrees C). Oral temperature and the presence or absence of shivering were recorded at 15-min intervals. After application of the selected warming method, patients in group 2 were warmer at all time intervals. Mean temperatures in the forced-air heating group and in group 1 were, respectively, 34.8 degrees C and 34.3 degrees C (P less than 0.05) at 15 min; 35.0 degrees C and 34.2 degrees C (P less than 0.01) at 30 min; 35.2 degrees C and 34.5 degrees C (P less than 0.05) at 45 min; 35.8 degrees C and 34.7 degrees C (P less than 0.001) at 60 min; 36.0 degrees C and 35.0 degrees C (P less than 0.01) at 75 min; and 36.0 degrees C and 35.0 degrees C (P less than 0.01) at 90 min. The incidence of shivering was significantly greater in group 1 at 15 and 45 min. In addition, time spent in the recovery room was significantly greater in group 1 than in group 2, 156.0 min versus 99.7 min (P less than 0.003).

The purpose of this study was to examine the effects of the increased sympathetic activity elicited by the upright posture on blood flow to exercising human forearm muscles. Six subjects performed light and heavy rhythmic forearm exercise. Trials were conducted with the subjects supine and standing. Forearm blood flow (FBF, plethysmography) and skin blood flow (laser Doppler) were measured during brief pauses in the contractions. Arterial blood pressure and heart rate were also measured. During the first 6 min of light exercise, blood flow was similar in the supine and standing positions (approximately 15 ml.min-1.100 ml-1); from minutes 7 to 20 FBF was approximately 3-7 ml.min-1.100 ml-1 less in the standing position (P less than 0.05). When 5 min of heavy exercise immediately followed the light exercise, FBF was approximately 30-35 ml.min-1.100 ml-1 in the supine position. These values were approximately 8-12 ml.min-1.100 ml-1 greater than those observed in the upright position (P less than 0.05). When light exercise did not precede 8 min of heavy exercise, the blood flow at the end of minute 1 was similar in the supine and standing positions but was approximately 6-9 ml.min-1.100 ml-1 lower in the standing position during minutes 2-8. Heart rate was always approximately 10-20 beats higher in the upright position (P less than 0.05). Forearm skin blood flow and mean arterial pressure were similar in the two positions, indicating that the changes in FBF resulted from differences in the caliber of the resistance vessels in the forearm muscles.(ABSTRACT TRUNCATED AT 250 WORDS)

We retrospectively reviewed 543 brachial plexus blocks performed on 526 outpatients. Most (98%) of the blocks were performed by means of the axillary approach. Various techniques were used, including paresthesia, transarterial fixation, nerve stimulation, or a combination of techniques; a high success rate was achieved with each of them. Only 7% of the blocks were incomplete and thus necessitated either general anesthesia or block supplementation with thiopental sodium and nitrous oxide. No persistent neurologic deficit was ascribed to the anesthetic technique. This review indicates that brachial plexus block, especially with use of the axillary approach, is a safe and effective option for outpatient surgical procedures on an upper extremity.

Spinal surgical procedures, such as placement of Harrington rods for correction of scoliosis, are associated with considerable perioperative blood loss and, hence, with the risks associated with homologous blood transfusions. To test the hypothesis that intraoperative autologous blood transfusions could decrease the amount of homologous blood needed in such operations, we conducted a two-part study: (1) a retrospective review of 142 patients in whom blood salvage was not used and (2) a prospective review of 28 patients who received autologous transfusions. Intraoperative autologous transfusion reduced the amount of homologous blood required by more than 50% (5.1 versus 2.0 units; P less than 0.001). The total amount of homologous blood required during the hospital stay was also significantly reduced by intraoperative autologous transfusion (6.0 versus 3.4 units; P less than 0.001). Induced hypotension in 81 of the 142 patients who did not receive autologous transfusions did not decrease the homologous blood transfusion requirements from those needed by the normotensive patients. We conclude that intraoperative autologous transfusion significantly reduces the need for homologous blood products in patients who undergo spinal surgical procedures. Induced hypotension, which did not affect transfusion requirements in our study, should be further evaluated in a blinded, prospective study.

Large doses of atracurium (1.5 mg/kg) (six times the ED95) can result in significant histamine release, resulting in systemic hypotension. The efficacy of histamine receptor blockade in attenuating atracurium induced hypotension was therefore studied. Four groups of seven patients each were studied: group I, control; group II, H1 blockade (1 mg/kg diphenhydramine); group III, H2 blockade (cimetidine 4 mg/kg); and group IV, H1 and H2 blockade (diphenhydramine 1 mg/kg and cimetidine 4 mg/kg). All patients were anesthetized with an intravenous narcotic-nitrous oxide technique and then given 1.5 mg/kg atracurium. In group I, mean arterial pressure (MAP) decreased 30 mm Hg after 2 minutes and remained 25 mm Hg below baseline at 3 minutes, a change significantly greater than that in group IV, in which MAP decreased 8 and 7 mm Hg, respectively. H1 receptor blockade was associated with no significant attenuation of changes in MAP. H2 receptor blockade alone was associated with significant decreases in MAP, possibly secondary to enhanced release of histamine via an antagonist effect on recently described H3 receptors. Plasma histamine levels increased significantly 2 minutes after atracurium administration and correlated with hemodynamic changes. It is concluded that combined H1 and H2 receptor blockade attenuates cardiovascular effects associated with large doses of atracurium in humans. Histamine-releasing agents may be contraindicated in patients subject to chronic H2 receptor blockade.