A comparison of rectal and intramuscular codeine phosphate in children following neurosurgery.

Codeine is frequently used for postoperative analgesia in children. Intramuscular injections are not ideal and the rectal route may be preferable. We compared rectal and intramuscular codeine administered following neurosurgery. 20 children (over 3 months) undergoing elective neurosurgical procedures, were randomized to receive either rectal or intramuscular codeine phospate (1 mg.kg-1) at the end of the procedure. Serum levels of codeine and morphine were assayed at intervals following administration (0, 30, 60, 120, 240 min). Fentanyl was the intraoperative analgesic and postoperative rescue analgesia was paracetamol, diclofenac and intramuscular codeine. The Children's Hospital of Eastern Ontario Pain Scale was used to assess analgesia. Peak codeine levels in both groups were observed at 30 min and morphine levels were consistently low. The plasma codeine levels were significantly greater at 30 and 60 min following intramuscular injection, and were associated with slightly better analgesia scores, but did not reach statistical significance. However, the peak plasma level occurred at similar times in both groups. Codeine is absorbed as rapidly via the rectal route compared with the intramuscular route but the peak levels are lower.

Rapid inhalation induction in children: 8% sevoflurane compared with 5% halothane.

Sevoflurane has a lower blood-gas solubility and a less pungent odour than halothane; this may allow more rapid induction of anaesthesia. In a randomized, blinded study, we compared the induction characteristics of maximum initial inspired concentration of 8% sevoflurane and 5% halothane using conventional vaporizers in children aged 3 months to 3 years. There was no statistically significant difference in induction times between the two groups: mean times to loss of consciousness were 1 min 12 s (SD 18 s, range 40 s-1 min 44 s) for sevoflurane and 1 min 16 s (SD 17 s, range 50 s-1 min 52 s) for halothane, although these times were shorter than in previous studies using a gradual increase in vapour concentration. A small number of complications were noted in both groups, although none interfered with induction of anaesthesia. Struggling scores were lower in the sevoflurane group than in the halothane group (chi-square for trends = 6.34, P < 0.02). A significant number (11 of 15) of parents of children in the sevoflurane group who had previous experience of halothane induction preferred sevoflurane (chi-square for trends = 4.03, P < 0.05). We conclude that with this technique, induction was rapid with both sevoflurane and halothane. Our assessment of patient struggling and parents' perceptions suggests that induction with sevoflurane was more pleasant than with halothane.

Pharmacological control of pulmonary blood flow with inhaled nitric oxide after the fenestrated Fontan operation.

BACKGROUND: A transient increase in pulmonary vascular resistance can result in hemodynamic compromise after a Fontan operation. An interatrial fenestration is designed to maintain cardiac output in these circumstances but may result in severe hypoxemia and a vicious circle due to hypoxemia induced pulmonary vasoconstriction. Our aim was to determine whether inhaled nitric oxide (iNO), a selective pulmonary vasodilator, could be used to reduce pulmonary vascular resistance in desaturated patients (SaO2 < or = 85%) after a fenestrated Fontan operation. METHODS AND RESULTS: Responses to iNO (20 ppm for 15 min) were assessed in 10 consecutive children with SaO2 < or = 85% and compared with 5 with SaO2 > 85% after a fenestrated Fontan operation. Exposure to iNO resulted in a significant increase in SaO2 (from 64 +/- 5% to 82 +/- 2%, P < .01) and reduction in transpulmonary gradient (TPG) (from 12.2 +/- 1 [SEM] to 9.6 +/- 1.1, P < .01) in patients with baseline SaO2 < or = 85%. Baseline saturation was a predictor of response to iNO, with a greater response in those with lower saturations (r = -.86, P < .01). In contrast, no significant effects were noted in PaO2 or TPG (from 122 +/- 46 mm Hg and 8 +/- 1.8 to 123 +/- 43 mm Hg and 7 +/- 1.2, respectively) in patients with baseline SaO2 > 85%. CONCLUSIONS: iNO improved both oxygenation and TPG in desaturated patients after the fenestrated Fontan operation, possibly by counteracting hypoxemia-induced pulmonary vasoconstriction. A trial of iNO should be considered in clinically unstable desaturated patients after the fenestrated Fontan operation.

Four patterns of response to inhaled nitric oxide for persistent pulmonary hypertension of the newborn.

OBJECTIVE: To determine the clinical role of inhaled nitric oxide (iNO) in the treatment of persistent pulmonary hypertension of the newborn (PPHN). STUDY DESIGN: Prospective open observational clinical study. SETTING: A regional cardiac and pediatric intensive care unit. METHODS: Twenty-five consecutive near-term neonates (> 35 weeks gestation) with severe PPHN (oxygenation index [OI] > 25) were given a trial of iNO of 20 ppm for 20 minutes. Neonates who showed a greater than 20% improvement in PaO2 as well as a decrease in the OI to below 40 were defined as responders and continued on this therapy. RESULTS: Four patterns of response emerged to the iNO therapy: Pattern 1 neonates (n = 2) did not respond to the initial trial of iNO-one survived. Pattern 2 neonates (n = 9) responded to the initial trial of iNO, but failed to sustain this response over 36 hours, as defined by a rise in the OI to > 40. Six survived, five with extracorporeal membrane oxygenation. Pattern 3 neonates (n = 11) responded to the initial trial of iNO, sustained this response, and were successfully weaned from iNO within 5 days--all survived to discharge. Pattern 4 neonates (n = 3) responded to the initial trial of iNO, but developed a sustained dependence on iNO for 3 to 6 weeks. All three died and lung histology revealed severe pulmonary hypoplasia and dysplasia. These neonates (pattern 4) not only required iNO for a longer period of time than did the sustained responders (pattern 3), but they required significantly higher doses of iNO during their first 5 days of iNO therapy. CONCLUSIONS: Early responses to iNO may not be sustained. Neonates with pulmonary hypoplasia and dysplasia may have a decreased sensitivity and differing time course of response to iNO when compared with patients who have PPHN in fully developed lungs.

Nitric oxide might reduce the need for extracorporeal support in children with critical postoperative pulmonary hypertension.

BACKGROUND: Postoperative pulmonary hypertension is a life-threatening, yet reversible complication of congenital heart operations. Although inhaled nitric oxide (iNO), a selective pulmonary vasodilator, has been shown extensively to improve short-term oxygenation and hemodynamic indices in these patients, its influence on patient outcome has not been evaluated. The purpose of this study was to assess retrospectively whether patients who fulfilled our criteria for extracorporeal life support (ECLS) for critical postoperative pulmonary hypertension still required ECLS after the administration of iNO therapy. METHODS: Since January 1992, 10 patients (age 3 days to 10 months) fulfilled the criteria at our institution for ECLS for postoperative pulmonary hypertension. Of these, 5 could not be separated from cardiopulmonary bypass because of pulmonary hypertension, and 5 had critical pulmonary hypertension (pulmonary arterial pressure approaching systemic arterial pressure) causing severe cardiopulmonary compromise. RESULTS: Six of the 10 ECLS candidates had a sustained response to iNO and survived to discharge from the hospital, without the need for rescue ECLS. Three patients still required ECLS after 30 minutes, 4 hours, and 8 hours of beginning iNO because of failing cardiac output, and 2 survived. The remaining patient died after 5 days of iNO therapy, but was no longer a candidate for ECLS because of sepsis and multiorgan system failure. CONCLUSIONS: Children with critical pulmonary hypertension unresponsive to maximal conventional treatment may be managed successfully with iNO without the need for rescue ECLS. A trial of iNO should therefore be given before the use of ECLS in these patients.