The effective time and concentration of nitrous oxide to reduce venipuncture pain in children

Study ObjectiveTo investigate the time of administration and concentration of inhaled nitrous oxide (N₂O) needed to reduce the pain associated with intravenous (IV) cannulation in children.DesignProspective, randomized study.SettingOperating room of a children's hospital.Patients73 ASA physical status I and II children, aged 6-15 years, scheduled for elective day or non-day surgery.InterventionsChildren were randomly allocated to one of 4 groups prior to IV insertion of a 24-gauge catheter in the dorsum of the hand: Group 1 (n = 18): 50% N₂O in O₂ for three minutes; Group 2 (n = 18): 50% N₂O in O₂ for 5 minutes; Group 3 (n = 18): 70% N₂O in O₂ for three minutes; or Group 4 (n = 19): 70% N₂O in O₂ for 5 minutes.MeasurementsJust after the venous cannulation, degree of pain was assessed by examining the faces of the patient by the parent and an operating room nurse.Main ResultsPain scores obtained from parents of children in Groups 3 and 4 were significantly lower than from those in Groups 1 and 2. Pain scores from the nurse in Group 3 was significantly lower than those in Group 1. However, there was no significant difference in pain score between Group 3 and Group 4. Frequency of side effects was similar among the 4 groups.ConclusionsSeventy percent N₂O in O₂ given for three minutes was effective for reducing venipuncture pain in children.     

Intravenous famotidine does not always change core temperature during general anesthesia

It has been reported that oral premedication with the H₂ receptor antagonist famotidine augmented intraoperative hypothermia. We again investigated whether the H₂ receptor antagonist famotidine significantly affected body temperature during open abdominal surgery under general anesthesia. We studied 20 female patients undergoing elective gynecological surgery. Participating patients were assigned randomly to one of two regimens: (1) 10 ml saline given intravenously just before induction of general anesthesia or (2) 20 mg famotidine in 10 ml saline given just before induction of general anesthesia. General anesthesia was induced by 2 mg·kg⁻¹ propofol and 0.1 mg·kg⁻¹ vecuronium. After tracheal intubation, anesthesia was maintained with sevoflurane (1%–2%) in nitrous oxide (2 l·min⁻¹) and oxygen (1 l·min⁻¹) along with 1–2 μg·kg⁻¹ fentanyl as needed. Tympanic temperature (T_Tym) was measured as the core temperature, and arteriovenous perfusion of the fingertip was evaluated using the forearmminus-fingertip skin-surface temperature gradient (Grad_a–f). T_Tym gradually and significantly decreased in both groups during anesthesia, and no significant differences in these values were observed between the two groups. Grad_a–f did not differ significantly between the two groups during anesthesia. We conclude that intravenous famotidine does not always change the core temperature during general anesthesia.     

Adenine phosphoribosyl transferase (APRT) deficiency and a novel sequence variant in APRT with phenotypic diversity and a literature review

Adenine phosphoribosyl transferase (APRT) deficiency is an autosomal recessive disorder and a rare cause of urolithiasis due to mutations in APRT (OMIM #102600). APRT deficiency results in increased urinary excretion of 2,8-dihydroxyadenine (DHA) which can cause urolithiasis and kidney failure. However, with prompt diagnosis, patients with APRT deficiency can be treated with xanthine oxidoreductase inhibitors which decrease urinary DHA excretion and improve outcomes. We report a pair of siblings, an 11-year-old brother and his 14-year-old sister with compound heterozygous variants c.270del (p.Lys91Serfs*46) and c.484_486del (p.Leu162del) in APRT with variable clinical presentation of APRT deficiency. The brother presented at 17 months of age with urolithiasis and severe acute kidney injury. His elder sister remained well and asymptomatic with normal kidney function and did not develop renal calculi. Brownish disk or sphere-like crystals with both concentric and radial markings were reported on urine microscopy in the sister on screening. The sister's diagnosis was confirmed with further laboratory evidence of absent red cell lysate APRT activity with corresponding elevated levels of urinary DHA. In conclusion, we identified a novel mutation in the APRT gene in a pair of siblings with greater phenotypic severity in the male.

     

Usefulness of simultaneous measurement of brain and muscle regional oxygen saturation in shock patients: A report of three cases

The regional oxygen saturation (rSO₂) values of brain and muscle tissues can be measured simultaneously even if blood pressure cannot be measured due to circulatory failure associated with shock and may continuously reflect the oxygen supply‐demand balance.