Dual bolus intravenous contrast injection technique for multiregion paediatric body CT.

OBJECTIVES: Optimal vascular and parenchymal enhancement for multi-region paediatric body computed tomography (CT) has many challenges. A variety of approaches are currently employed, associated with varying image quality and radiation dose implications. We present a dual bolus intravenous (DBI) contrast technique for single-acquisition imaging of the chest, abdomen and pelvis, with evaluation of multi-compartmental vascular enhancement. METHODS: A DBI regime was designed for use with a programmable dual head pump injector. A larger initial bolus (two-thirds volume) is followed by a smaller bolus (one-third volume) before imaging the chest, abdomen and pelvis in a single acquisition, 45-65 seconds from the start of initial injection. Flow rates and second bolus timing were tailored to patient weight and contrast volume, using five weight categories. Multi-compartmental vascular opacification was graded and image quality was assessed in a cohort of 130 patients. RESULTS: The DBI technique resulted in concordant multi-compartmental (thoracic aortic, pulmonary arterial, abdominal aortic and portal venous) vascular enhancement. Early splenic parenchymal enhancement artefacts and alterations to renal enhancement were observed. CONCLUSION: We present a weight-stratified dual bolus intravenous contrast technique to improve image quality in paediatric multi-region body CT. KEY POINTS: • In children, optimal vascular and parenchymal enhancement in multi-region CT is challenging. • A dual bolus contrast technique offers concordant arterial and portal venous opacification. • Adaptation to patient size is achieved by stratification into five weight categories. • Dose penalties of 'overlap' and 'dual phase' imaging techniques can be avoided.

Carcinoid syndrome: comparison of pretreatment regimes in the same patient.

Severe difficulties were encountered when a 47 year old man, with symptomatic carcinoid pretreated with ketanserin 80 mg twice daily was anaesthetised for hepatic arterial embolisation. The same patient, having had three days pretreatment with parachlorophenylalanine 500 mg four times daily and cyproheptadine 4 mg three times daily in addition to the ketanserin, was anaesthetised a week later without any difficulties. On the second occasion much better symptom control had been achieved. It is suggested that pretreatment with ketanserin alone is insufficient in severely symptomatic carcinoid and that the best possible medical control of symptoms should be achieved before anaesthesia.

Temazepam and trimeprazine compared with placebo as premedication in children. An investigation extended into the first 2 weeks at home.

Temazepam, trimeprazine and placebo were compared as premedication in 85 children undergoing routine otolaryngological operations. Premedication with trimeprazine caused significantly more sedation than temazepam or placebo in patients on arrival in the anaesthetic room (P less than 0.02). Recovery time was significantly longer after trimeprazine than temazepam or placebo (P less than 0.012). Significantly more children (P less than 0.05) failed to recall a picture shown immediately before induction after trimeprazine and temazepam than with placebo. Fewer patients vomited after operation with trimeprazine than with temazepam or placebo (P less than 0.01). The majority of children exhibited some behavioural problem during the first 2 weeks at home, although this rarely lasted for more than a few days. More children exhibited apathetic/withdrawn behaviour after receiving placebo (P less than 0.05), although the significance of this should be interpreted with caution.