Optimum use of a spacer device

Nedocromil sodium given by the Fisonair spacer should be inhaled immediately. Multiple actuations into the spacer should be avoided. Delay of 20 seconds before sampling reduced the amount of drug available for inhalation in the respirable range by 81%. Placing two actuations into the spacer reduced the amount of drug available by 47%.     

The incidence, aetiology and management of anaphylaxis presenting to an accident and emergency department

We retrospectively studied anaphylaxis in an A&E department from computerized records. In 1993 (Study A), of 55,000 patients seen in casualty, nine had severe anaphylaxis (ANA) with loss of consciousness (LOC) or fainting (about 1: 6000). Fifteen had generalized allergic reactions (GR) without LOC or fainting, but including dyspnoea due to laryngeal oedema or asthma, angioedema and/or urticaria. Thus there were 24 (about 1:2300) generalized reactions involving hypotension and/or respiratory difficulty. A further case diagnosed as hyperventilation syndrome was probably a wasp sting GR. Six cases of urticaria and/or angioedema were also identified. Of the nine with ANA, a possible cause was identified in eight (3 stings; 2 drugs; 3 foods). There was delay in arrival in A&E: hypotension was noted in three and had resolved spontaneously in six. Only 3/9 were related with adrenaline: i.v. hydrocortisone and chlorpheniramine was the mainstay of treatment. No investigation was recommended nor advice given on future management. Four patients were later referred to our allergy clinic by their GPs. In study B (aug-Oct 1994), nine cases of ANA were identified (1:1500), eight due to bee or wasp stings. The increased incidence was probably related to more detailed history-taking. Only three were treated with adrenaline. The use of adrenaline for future anaphylaxis was discussed with six patients, and five were referred to our allergy clinic. A reaction to the same allergen had occurred previously in 24%. Improved awareness of anaphylaxis and its management is necessary.      

Lowest hematocrit on bypass and adverse outcomes associated with coronary artery bypass grafting. Northern New England Cardiovascular Disease Study Group

BACKGROUND: Cardiac surgery patients' hematocrits frequently fall to low levels during cardiopulmonary bypass. METHODS: We investigated the association between nadir hematocrit and in-hospital mortality and other adverse outcomes in a consecutive series of 6,980 patients undergoing isolated coronary artery bypass graft surgery. The lowest hematocrit during cardiopulmonary bypass was recorded for each patient. Patients were divided into categories based on their lowest hematocrit. Women had a lower hematocrit during bypass than men but both sexes are represented in each category. RESULTS: After adjustment for preoperative differences in patient and disease characteristics, the lowest hematocrit during cardiopulmonary bypass was significantly associated with increased risk of in-hospital mortality, intra- or postoperative placement of an intraaortic balloon pump and return to cardiopulmonary bypass after attempted separation. Smaller patients and those with a lower preoperative hematocrit are at higher risk of having a low hematocrit during cardiopulmonary bypass. CONCLUSIONS: Female patients and patients with smaller body surface area may be more hemodiluted than larger patients. Minimizing intraoperative anemia may result in improved outcomes for this subgroup of patients.     

Obstetrical magnetic resonance imaging: fetal anatomy

Nine patients who were 34-36 weeks pregnant underwent magnetic resonance (MR) imaging. Sagittal images using spin echo technique (TR 2.0 sec, TE 28 msec) were optimal for delineating fetal anatomy. The fetal cardiovascular, pulmonary, and central nervous systems were depicted in all cases. The heart and major vessels were readily seen due to the natural contrast of flowing blood. The intensity of the fluid-filled lungs greatly increased with a longer TR or TE, delimiting thorax from liver. The brain was relatively featureless due to the lack of gray-white matter differentiation. The umbilical cord within the amniotic fluid and its insertion into the placenta and fetus was identified in all cases. MR is a new modality for fetal imaging that offers tissue-characterization information that complements the superior anatomic detail of ultrasound scanning.     

Twenty-four-hour intragastric pH profiles and pharmacokinetics following single and repeated oral administration of the proton pump inhibitor pantoprazole in comparison to omeprazole.

BACKGROUND: Pantoprazole is a proton pump inhibitor characterized by a low potential to interact with the cytochrome P450 enzyme system in man. Its effect on intragastric pH following single and repeated oral intake was investigated in comparison to omeprazole by continuous intragastric pH-metry at doses recommended for treatment of peptic ulcer disease. METHODS: Sixteen healthy male subjects underwent two dosing periods. From day 1 to day 7, they were given once daily by mouth 40 mg pantoprazole in one period and 20 mg omeprazole in the other period, according to a double-blind randomized crossover design. Twenty-four-hour intragastric pH was recorded and frequent blood samples for pharmacokinetic analysis were taken on day 1 and day 7. A placebo pH profile was obtained prior to each treatment period. RESULTS: Pantoprazole was significantly more effective than omeprazole with regard to increase in 24-h and daytime pH, following both single (median 24-h pH: 1.45 vs. 1.3, P < 0.05; median daytime pH: 1.6 vs. 1.3, P < 0.01) and repeated (median 24-h pH: 3.15 vs. 2.05, P < 0.01; median daytime pH: 3.8 vs. 2.65, P < 0.05) oral intake. As compared to the first dose, repeated administration of both drugs markedly increased the effect on intragastric pH. With pantoprazole, steady- state serum concentrations were obtained after the first dose, but not with omeprazole. Both drugs were well tolerated without relevant changes in vital signs of clinical laboratory parameters. CONCLUSION: Pantoprazole 40 mg is significantly more effective than omeprazole 20 mg in raising intragastric pH.