Arteriovenous Malformation of the Stomach

Of the multitude of sources capable of producing massive hemorrhage from the gastrointestinal tract, one of the rarest forms is arteriovenous malformation (AVM) of the stomach. The typical patient is a middle-aged male who presents with recurrent painless massive hematemesis and an unremarkable past medical history. Until recently the diagnostic work-up has often presented a dilemma, with the lesion rarely being confirmed prior to laparotomy. The patient whom we have encountertd with AVM of the stomach confirms our belief in the use of visceral angiography as a vital tool in the diagnosis of obscure gastrointestinal bleeding. We present this case as one which is unusual in its diagnostic work-up, therapeutic approach and pathologic findings.     

PHARMACOKINETICS OF ALFENTANIL DURING AND AFTER A FIXED RATE INFUSION

Twenty-nine patients (age range 14–81 yr) undergoing orthopaedicsurgery received alfentanil 100 µg kg^–1 given astwo i.v. boluses followed by a fixed rate infusion of 1 µgkg^–1 min^–1 for 44–445 min. Additional 1-mgbolus doses of alfentanil were administered as required. Plasmasamples were assayed for alfentanil using radio-immunoassay.Pharmacokinetic parameters were estimated by a model-independentapproach and by curve-fitting. Regression analysis showed nostatistical relationship between T, CI or Vd and the durationof the infusion, total dose or body weight. We found no significantcorrelation between age and T of alfentanil for patients youngerthan 40 yr. For patients older than 40 yr, T increased linearlywith age. There was no significant decrease in Cl with age,although the lower values for CI (100–200 ml min^–1)were generally found in subjects older than 60 yr. The presentstudy demonstrated that a 100-µg kg^–1 loading doseand a 1-µg kg^–1 min^–1 infusion may be appropriatefor analgesia in general surgical procedures.