Meniscal History lesions and ligament ruptures cannot be diagnosed on a The possibility of a lesion ofthe internal structures of the plain x-ray order minocin 50mg visa. The Everything usually happens very quickly and children are following conclusions can be drawn on the basis of the often unable to recall the precise circumstances purchase 50 mg minocin overnight delivery. Typical aspirate: mechanisms are injuries in a flexion/external rotation/ Serous effusion: Not a consequence of a recent internal valgus position or with a hyperextended knee order minocin 50mg mastercard. The most likely fracture is a bony avulsion of the anterior cruciate ligament at the Stability testing intercondylar eminence, although other intra-articu- Lachman test, i. Another Testing for the meniscus signs possibility is a recent, traumatic dislocation of the test whether pain is elicited during internal and exter- patella with tearing of the retinacula. Knee traumatized 2 weeks or more in the past Other imaging procedures History The prospect of being able to diagnose internal knee le- If the trauma occurred slightly further back in the past, sions by ultrasound raised great hopes, particularly since it the following questions are relevant: is a cheap, painless and non-invasive investigation meth- ▬ Does genuine locking occur (the knee can neither be od. Periarticular structures (collateral ligaments, tendons, flexed nor extended from a particular position)? Greater difficulties ▬ Does pseudolocking occur (in a particular position the are posed, however, by the internal structures (particu- knee has to overcome an occasionally painful snap- larly the anterior cruciate ligament), although certain ping )? Even though certain After 2 weeks, the acute pain has subsided and the ef- authors have reported a close correlation between MRI fusion has also usually regressed. The knee can now be and arthroscopic findings, the sensitivity of the MRI examined thoroughly. We proceed according to the fol- scan is generally poor, particularly in children under 12 lowing examination protocol (the examination technique years of age, and the MRI is no more reliable in terms of is described in detail in chapter 3. Furthermore, it is difficult to assess the need for treat- Inspection ment on the basis of MRI findings.
It is not known for certain when this risk develops minocin 50mg discount, but most agree that succinylcholine should not be used in burn patients after 48 h following injury buy cheap minocin 50mg on-line. Succinyl- choline probably should not be used until at least a year after wounds have healed cheap 50 mg minocin visa. In contrast to succinylcholine, most nondepolarizing muscle relaxants re- quire larger and more frequent dosages to maintain muscle relaxation because of the marked resistance that occurs after burns. Stan- dard dosages of mivacurium retain their efficacy in burn patients. Mivacurium is metabolized by plasma cholinesterase and this enzyme is decreased after burns. This is thought to increase the concentration of mivacurium at its site of action and delay its elimination, so that dosing need not be altered for burn patients. MANAGEMENT OF ANESTHESIA Monitors The choice of hemodynamic monitors is a major concern in planning anesthetic management for burn patients. Since access may be limited and difficult in these patients, careful preoperative assessment is necessary for effective management. As with any critically ill patient, the choice of monitors in burned patients depends on the extent of the patient’s injury, physiological state, and planned surgery. An arterial catheter provides much information, including pulmonary and metabolic status as well as hemodynamic function. When blood loss is expected to be extensive and rapid, blood pressure may change more quickly than the interval between cycles of a noninvasive blood pressure monitor. In this case, an arterial catheter provides beat-to-beat monitoring capability. As explained below, direct arterial pressure monitoring also allows observation of wave form and respiratory variation in systolic blood pressure, which are very useful for titrating fluid admin- istration for volume replacement during periods of rapid blood loss. An arterial catheter also allows arterial blood sampling for blood gas analysis. This helps with the assessment of tissue perfusion as well as pulmonary function.
A specific concern about the use of tracheos- tomy in burn patients is that order minocin 50mg with mastercard, soon after burn buy cheap minocin 50mg, pronounced edema from cutaneous neck burns may cause dislodgment of the tracheostomy tube buy minocin 50 mg amex. Under these circum- stances, loss of the airway may be life-threatening. Even in the presence of facial burns, an oral endotracheal tube may be more secure than a tracheostomy when thermal injury to the neck results in extensive edema. One factor contributing to the controversy regarding the timing of conver- sion from translaryngeal intubation to tracheostomy in patients with inhalation injury is that it is very difficult to evaluate accurately the severity of an inhalation injury. This makes it difficult to predict which patients will require prolonged ventilation. The factors that they identified (percentage of body surface area with full-thickness burns, age, presence of inhalation injury, and worst PO2/FiO2 on postburn day 3) were used to develop an equation to predict the probability of prolonged ventilator dependence. Although this equation was found to be sensitive and specific for what they considered for prolonged ventilator dependence, many institutions will not perform tracheostomy at 2 weeks if there is no laryngeal injury and pulmonary function is improving. The reason to convert from translaryngeal intubation is to prevent mucosal disruption and subsequent scarring. The time required for mu- cosal disruption by an endotracheal tube will vary depending on presence of laryngeal inhalation injury, patient movement (e. In the absence of laryn- geal injury, conversion to tracheostomy can be delayed if there are indications that separation from mechanical ventilatory support may soon be possible. Tracheostomy clearly offers advantages over translaryngeal intubation in certain patients in whom earlier conversion to tracheostomy reduces morbidity 76 Woodson et al. Trache- ostomy is an invasive procedure with a low but finite incidence of complications that can be very serious or lethal. The risk of subglottic stenosis in patients without laryngeal inhalation injury and who do not require prolonged ventilation should be higher after tracheostomy than after several atraumatic intubations for serial debridement and grafting procedures.