ABSTRACT
Congenital anomalies of the arch of the atlas in the sense of clefts are uncommon. As such anomalies may be mistaken for fractures, radiologists should be aware of them. A case of aplasia of the right part of the posterior arch producing wide, asymmetric medial cleft of the atlas is presented. The patient also had hypoplastic left part of the arch with the lateral cleft formed by a secondary ossification centre in the posterior tubercle. This combination of anomalies has not formerly been presented in literature.
Subject(s)
Cervical Atlas/abnormalities , Adult , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/pathology , Humans , Male , RadiographyABSTRACT
The effect of submaximal neuromuscular blockade (SMNB) on lung and chest wall mechanics was studied in six normal, awake subjects infused with pancuronium. Measurements of static lung volumes, specific airway conductance (sGaw), maximum expiratory and inspiratory flow-volume (MEFV, MIFV) curves, and static pressure-volume (PV) curves of the lung and of the relaxed chest wall were obtained after lung recoil pressure (Pst(L)) at full inflation had been reduced to 60 +/- 10% of control. Inspiratory capacity was decreased, but residual volume was not increased. Inspiratory PV curve of the lung was not modified, and the observed decrease in expiratory compliance and the slight increase in Pst(L) during deflation were compatible with the altered lung volume history. SMNB did not modify sGaw nor the relationship between Pst(L) and MEF; by contrast it markedly reduced MIF rates. Finally, SMNB transposed the chest wall PV curve to higher levels on the pressure axis (it decreased the outward pull of the chest wall) without greatly affecting its slope, and thereby it reduced the resting level of the respiratory system. We conclude that 1) muscle weakness per se does not affect the eleastic properties of the lungs and airways, and 2) involuntary respiratory muscle activity influences the elastic recoil of the chest wall. We believe this muscle activity originates from muscle spindles, and lies essentially in the inspiratory portion of the intercostal musculature.
Subject(s)
Diaphragm/drug effects , Intercostal Muscles/drug effects , Pancuronium/pharmacology , Respiration/drug effects , Adult , Airway Resistance , Atropine/pharmacology , Expiratory Reserve Volume , Functional Residual Capacity , Humans , Lung Volume Measurements , Male , Maximal Expiratory Flow-Volume Curves , Nerve Block , Peak Expiratory Flow Rate , Pressure , Pulmonary Ventilation , Total Lung Capacity , Vital CapacityABSTRACT
Two hundred current surgical procedures were done in adult patients using neuroleptanalgesia with either methohexital (1 mg/kg) or etomidate induction (0.3 mg/kg) in half of the cases. The cardiovascular function was less altered with etomidate (less occurrence of tachycardia, blood pressure drops or systolo-diastolic pinching). The etomidate dosage chosen more often gave an immediate satisfactory sleep. However, with methohexital induction, less signs of awakening were observed during the surgical procedure. The frequent postoperative somnolence also points, although indirectly, to a longer residual effect of the barbiturate. Both drugs sometimes gave erythema. The injection of etomidate was more frequently painful in the arm. On the other hand, hiccups occurred with methohexital induction only. Etomidate induced myoclonia in one-third of the cases premedicated with diazepam and after preliminary injection of a minimal amount of fentanyl. Without these precautions, myoclonia can occur in two-thirds of the patients. However, these myoclonia are bothersome and of prolonged duration in rare instances and would be of real annoyance only when this drug would be used alone for surgical procedures of short duration where perfect patient immobility is required. We therefore conclude and confirm that etomidate is a good induction agent for neuroleptanalgesia anesthesia procedures.
