Objectives:To investigate whether the muscle strength decrease that follows anterior cruciate ligament (ACL) reconstruction would lead to different cardiorespiratory adjustments during dynamic exercise.Method:Eighteen active male subjects were submitted to isokinetic evaluation of knee flexor and extensor muscles four months after ACL surgery. Thigh circumference was also measured and an incremental unilateral cardiopulmonary exercise test was performed separately for both involved and uninvolved lower limbs in order to compare heart rate, oxygen consumption, minute ventilation, and ventilatory pattern (breath rate, tidal volume, inspiratory time, expiratory time, tidal volume/inspiratory time) at three different workloads (moderate, anaerobic threshold, and maximal).Results:There was a significant difference between isokinetic extensor peak torque measured in the involved (116.5±29.1 Nm) and uninvolved (220.8±40.4 Nm) limbs, p=0.000. Isokinetic flexor peak torque was also lower in the involved limb than in the uninvolved limb (107.8±15.4 and 132.5±26.3 Nm, p=0.004, respectively). Lower values were also found in involved thigh circumference as compared with uninvolved limb (46.9±4.3 and 48.5±3.9 cm, p=0.005, respectively). No differences were found between the lower limbs in any of the variables of the incremental cardiopulmonary tests at all exercise intensities.Conclusions:Our findings indicate that, four months after ACL surgery, there is a significant deficit in isokinetic strength in the involved limb, but these differences in muscle strength requirement do not produce differences in the cardiorespiratory adjustments to exercise. Based on the hypotheses from the literature which explain the differences in the physiological responses to exercise for different muscle masses, we can deduce that, after 4 months of a rehabilitation program after an ACL reconstruction, individuals probably do not present differences in muscle oxidative and peripheral perfusion capacities that could elicit higher levels of peripheral cardiorepiratory stimulus during exercise.

Objective. The objective of this study was to investigate whether routine medical testing before cataract surgery reduces the rate of complications during the perioperative period in adults. Methods. The study was carried out in an academic medical center in Brazil, between 10 February 2000 and 10 January 2001. The scheduled cataract operations were randomly assigned to one of two groups: 1) to be preceded by routine testing (the "routine-testing group") or 2) not to be preceded by routine medical testing (the "selective-testing group"). If the patient was assigned to the selective-testing group, it was requested that no preoperative testing be performed unless the patient presented with a new or worsening medical problem that would warrant medical evaluation with testing. In the case of patients assigned to the routine-testing group, three tests were requested: a 12-lead electrocardiogram, a complete blood count, and measurements of serum glucose. Results. The sample of 1 025 patients scheduled to undergo cataract surgery was comprised of 512 assigned to the routine-testing group and of 513 assigned to the selective-testing group. The two groups had similar proportions of operations canceled and not subsequently rescheduled, 2% in each group. The cumulative rate of medical events was similar in the two groups, 9.6% in the routine-testing group and 9.7% in the selective-testing group (P = 0.923). The types of medical events were also similar in both groups. Discussion. The results of this study suggest that routine medical testing before cataract surgery does not reduce the rate of complications during the perioperative period. The results also suggest it would be more efficient not to request routine preoperative tests unless indicated by patient history or physical examination.

Objetivos. El objetivo de este estudio consistió en determinar si la realización rutinaria de pruebas clínicas antes de la cirugía de cataratas reduce la tasa de complicaciones perioperatorias en adultos. Métodos. El estudio se realizó en un centro médico universitario de Brasil entre el 10 de febrero de 2000 y el 10 de enero de 2001. Los pacientes con operaciones de cataratas programadas fueron asignados aleatoriamente a un grupo en el que las pruebas preoperatorias se realizaron de forma rutinaria (grupo R) o a un grupo en el que se realizaron de forma selectiva (grupo S). A los pacientes asignados al grupo S solo se les solicitaron pruebas preoperatorias en caso de que presentaran un problema médico nuevo o agravado que justificara su realización. En el grupo R se practicaron tres pruebas preoperatorias de forma rutinaria: un electrocardiograma de 12 derivaciones, un hemograma completo y una determinación de la glucemia. Resultados. De los 1 025 pacientes estudiados, 512 fueron asignados al grupo R y 513 al grupo S. La proporción de intervenciones canceladas y no programadas nuevamente fue similar en ambos grupos: 2% en cada uno. La tasa acumulada de complicaciones médicas también fue similar en ambos grupos: 9,6% en el grupo R y 9,7% en el S (P = 0,923). Lo mismo ocurrió con los tipos de complicaciones médicas observadas. Conclusiones. Los resultados de este estudio indican que la realización rutinaria de pruebas médicas antes de la cirugía de cataratas no reduce la tasa de complicaciones perioperatorias y que parece ser más eficiente no solicitar pruebas preoperatorias, a no ser que la historia clínica o la exploración física del paciente indiquen su realización.