Safe and effective IV regional anesthesia for use in the emergency department

Feasibility of a reduction protocol in the emergency department for diaphyseal forearm fractures in children

INTRODUCTION

Diaphyseal forearm fractures are very common pediatric traumas. At present, distal radius metaphyseal fractures are often successfully treated with closed reduction by emergency physicians. However, the management of diaphyseal fractures remains controversial. The purpose of this study was to analyze the results of diaphyseal forearm fractures in the emergency department (ED) in children.

MATERIALS AND METHODS

In a prospective 2-year-study, all closed diaphyseal forearm fractures in patients under 15, with an angle of >15° and treated by closed reduction in the ED were included. Fractures with overlapping fragments were excluded. Reduction was performed by an emergency physician, with a standardized analgesic protocol (painkillers and nitrous oxide). Clinical tolerance was checked within the first 24hours, and the radiographic stability of reduction was assessed at days 8 and 15. Initial and final follow-up radiographs were analyzed. Elbow and wrist range of motion was assessed at the final follow-up.

RESULTS

Sixty patients (41 boys and 19 girls) were included. Mean age was 5.2 years old (±3). At initial evaluation, the maximum angle was 30° (±11.3). After reduction, the maximum angle was significantly reduced (30° vs. 5°, P<0.001). Mean immobilization in a cast was 11.7 weeks (±2). There were no cast related complications in any of these children. There was no surgery for secondary displacement. Full range of motion was obtained in all patients at the final follow-up.

DISCUSSION

The outcome of conservative treatment of closed diaphyseal forearm fractures, without overlapping fragments was excellent. However, reduction is usually performed in the operating room by orthopedic surgeons under general anesthesia and requires hospitalization, which is very expensive. The results of this study show that high quality care may be obtained in the ED by a trained and experienced team. These results are similar to those for distal metaphyseal fractures, which could extend the indications for reduction in the ED.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Safety and effectiveness of intravenous regional anesthesia (Bier block) for outpatient management of forearm trauma

Objective:

To assess the safety and effectiveness of intravenous regional anesthesia (Bier block) in the management of forearm injuries (i.e., forearm, wrist or hand) by primary care physicians at a diagnostic and treatment facility.

Methods:

A retrospective review was conducted of all patients at a single centre who underwent a Bier block for forearm injuries between September 2000 and March 2005.

Results:

1816 Bier blocks were performed on 1804 patients (64% male) during the study period. Patient age ranged from 4–70 (mean 25) years. Wrist fractures requiring reduction were the most common diagnosis. Adverse events were recorded in 9 cases (0.50%, 95% confidence interval 0.23%–0.94%): 1 case of medication error (0.06%); 3 of improper cuff inflation (0.17%); and 5 of inadequate analgesia (0.28%). None of the adverse events resulted in failure to complete the procedure or in serious morbidity or mortality.

Conclusion:

Bier block anesthesia is a safe, effective and reliable technique in an outpatient primary care setting. This technique is a useful modality for physicians who manage acute upper-extremity injuries.

Challenges facing the anesthesiologist in the emergency department

PURPOSE OF REVIEW

This review focuses on developments in airway management and concious sedation/analgesic techniques employed by anesthesiologists in the emergency department.

RECENT FINDINGS

Emergency medicine physicians routinely employ airway devices and techniques that were previously reserved for anesthesiologists. An understanding of the uses and limitations of these devices are essential for successful outcomes. Anesthesiologists responding to the emergency department may be faced with soiled or traumatized airways. The use of newer devices in cervical trauma and the difficult airway is reviewed. Consious sedation in the emergency department is also reviewed. There are no published recommendations demonstrating the advantage of specific agents for sedation in the emergency department. A wide variety of medications and techniques are currently being employed. Studies indicate that the incidence of adverse effects from these agents range from less than 1% to almost 30%. Various organizations have published guidelines detailing the appropriate protocols and equipment that must be present in the emergency department to monitor patients undergoing conscious sedation. These recommendations have not been universally implemented, and several recent studies suggest that a substantial number of emergency departments may have major deficiencies.

SUMMARY

The consultant anesthesiologist responding to a critical airway may face a variety of challenges, including traumatized or soiled airways, patients with cervical spine fractures, and patients who have undergone sedation techniques that may have progressed to deep and general anesthesia. Anesthesiologists may also face the challenge of responding to these emergent situations without all the equipment or adequately trained support staff necessary to handle those emergencies safely.

Bier block exsanguination: a volumetric comparison and venous pressure study

OBJECTIVES

Intravenous regional anesthesia (IVRA) is a useful ED anesthetic technique. However, venous pressure elevation during injection can cause anesthetic leakage and toxicity. This is minimized by preinjection limb exsanguination. Although standard, Esmarch exsanguination is intolerable with limb trauma. Thus, the authors' objective was to study alternative methods.

METHODS

Volunteers had upper limb exsanguination performed by Esmarch bandage, arm elevation/arterial compression (AE/AC), and a pneumatic vinyl splint. Resultant volume changes, measured by volume displacement, were normalized, and expressed as percent decreases from baseline. Volume changes of all three methods were compared. The physiologic effectiveness of the AE/AC method was tested by measuring IV pressures during simulated IVRA. Attainment of maximum venous pressure (MVP) indicated leakage under the tourniquet.

RESULTS

All methods reduced limb volume compared with baseline (p < 0.05). No difference occurred between AE/AC and vinyl splint exsanguination (p > 0.99), but neither method was as effective as Esmarch (p < 0.05). Gender differences were noted in absolute volumes exsanguinated, but there was no difference in percent exsanguination. The AE/AC method was the simplest procedure to perform. Peak IV pressure during simulated IVRA after AE/AC was 85 mm Hg (males), and 199 mm Hg (females) (p < 0.05). The MVP was not reached.

CONCLUSIONS

While Esmarch was the most effective exsanguinating method, the two alternatives provided significant and equivalent decreases in limb volume. The AE/AC technique was physiologically effective in preventing attainment of MVP. Further studies are indicated to determine the clinical effectiveness of this technique in providing anesthesia for patients with limb trauma.

Anesthesia and analgesia for the ambulatory management of fractures in children

The goal of anesthesia in the ambulatory management of fractures in children is to provide analgesia and relieve anxiety in order to facilitate successful closed treatment of the skeletal injury. Numerous techniques short of general anesthesia are available. These methods include blocks (local, regional, and intravenous), sedation (conscious and deep), and dissociative anesthesia (ketamine sedation). Important factors in choosing a particular technique include ease of administration, efficacy, safety, cost, and patient and parent acceptance. Local and regional techniques, such as hematoma, axillary, and intravenous regional blocks, are particularly effective for upper-extremity fractures. Sedation with inhalation agents, such as nitrous oxide, and parenterally administered narcotic-benzodiazepine combinations, are not region-specific and are suitable for patients over a wide range of ages. Ketamine sedation is an excellent choice for children less than 10 years old. With any technique, proper monitoring and adherence to safety guidelines are essential.

Randomized double-blind trial of low- and moderate-dose lidocaine regional anesthesia for forearm fractures in childhood

We undertook a randomized double-blind trial to compare the efficacy of 1.5 mg/kg body weight (low dose) and 3 mg/kg (moderate dose) lidocaine regional anesthesia for closed reductions of forearm fractures in childhood. Of the 283 children studied, 143 were randomized to the moderate-dose group and 140 to the low-dose group. The characteristics of the children and their injuries did not differ significantly. There were no complications due to lidocaine toxicity. In children with angulated and incompletely displaced fractures, satisfactory anesthesia was achieved in 94% of those receiving the low dose and in 97% of those receiving the moderate dose of lidocaine. In children with completely displaced fractures, satisfactory anesthesia was achieved in 93% of those receiving the moderate dose but in only 67% of those receiving the low dose of lidocaine. We conclude that the low-dose lidocaine protocol is suitable for children requiring closed reductions of angulated and incompletely displaced fractures of the forearm. In contrast, the moderate-dose lidocaine protocol is more reliable in children with displaced forearm fractures. Meticulous adherence to the protocols is essential to prevent systemic lidocaine toxicity from premature deflation of the tourniquet. This potential risk is further reduced by use of the low-dose protocol, which is applicable to approximately 70% of the children with forearm fractures requiring closed reductions.

Iatrogenic compartment syndrome from hypertonic saline injection in Bier block

A case study of an iatrogenic forearm compartment syndrome is presented. The patient underwent intravenous regional anesthesia (Bier's block) for an attempted closed reduction of a Bennett's fracture. Hypertonic saline (23.4%) was inadvertently used as a lidocaine diluent for the Bier's block, and after tourniquet release, the patient developed signs and symptoms of an acute compartment syndrome. An emergent fasciotomy was required. A review of the theoretical pathogenesis of compartment syndrome resulting from intravenous injection of hypertonic saline is presented. While vein sclerosis from i.v. hypertonic saline may play a role in the development of a compartment syndrome, we speculate that the major factor was an increase in the extracellular tissue fluid volume resulting from osmotic equilibrium after the tourniquet was released. The need for meticulous attention to details when performing this technique is emphasized.

Pediatric analgesia and sedation

Sedation and analgesia are essential components of the ED management of pediatric patients. Used appropriately, there are a number of medications and techniques that can be used safely in the emergency care of infants and children. Emergency physicians should be competent in the use of multiple sedatives and analgesics. Adequate equipment and monitoring, staff training, discharge instructions and continuous quality management should be an integral part of the ED use of these agents.

Intravenous regional anesthesia for outpatient foot and ankle surgery: a prospective study

A prospective study was undertaken in 39 patients undergoing 48 foot and ankle procedures using intravenous regional anesthesia (IVRA). IVRA was administered using 35 cc of 0.33% or 0.5% lidocaine. Single tourniquets inflated to 250 mm Hg were used at the ankle level. No supplemental analgesia or sedation was used. Those requiring supplemental local anesthetic infiltration were defined as IVRA failures. Thirty-one of the 39 patients (79.5%) tolerated the procedures with little or no discomfort, and 8 (20.5%) required additional local infiltration with 1% lidocaine. All 39 patients completed the procedures at the outpatient surgical unit without requiring conversion to other forms of anesthesia. Patchy non-anesthetic areas were noted in 14 patients (36.8%). In 7 patients, because the non-anesthetic areas were excluded from the operative fields, the procedures were completed without discomfort. However, in 8 patients where the non-anesthetic areas were directly involved in the operative fields, supplemental local anesthesia was required. Only 1 of the 39 patients complained of tourniquet pain. IVRA compared favorably with other methods of regional anesthesia in the lower extremity with respect to ease of technique, speed of onset, safety, and patient acceptance. However, it appears that it is less reliable than IVRA in the upper extremity. The reasons for this difference will require further investigation.