Ligation of a patent ductus arteriosus under fentanyl anesthesia improves protein metabolism in premature neonates

Anesthetic management of a patient with Edwards syndrome

The use of suxamethonium in our case was uneventful and despite craniofacial anomalies, airway management was straightforward. This case illustrates that pediatric patients with trisomy 18, presenting with potentially acute life‐threatening conditions and requiring emergency major surgery can be managed successfully with a multidisciplinary approach.

Anesthetic technique and postoperative outcome in preterm infants undergoing PDA closure

OBJECTIVE

To describe the various anesthetic techniques used for surgical closure of PDA in premature infants at the Montreal Children's Hospital and assess their impact on postoperative outcome.

STUDY DESIGN

The charts of all preterms who underwent PDA ligation during a 21-month period were reviewed for preoperative status, intraoperative anesthetic management and postoperative outcome. We determined the associations between independent variables and two postoperative outcome variables: unstable postoperative respiratory course (UPRC) and hypotension.

RESULT

The mean weight at surgery of the 33 infants was 1.031±0.29 kg. All infants, but one, received intraoperative opioids. Eight patients presented UPRC. Mean fentanyl doses were 5.3±2.6 mcg kg(-1) for patients with UPRC vs 22.6±16.6 mcg kg(-1) for patients without UPRC (P=0.004). Applying the receiver-operator characteristic curve (ROC), 10.5 mcg kg(-1) of fentanyl was established as the dose that discriminated and identified patients who experienced UPRC. The postnatal and postmenstrual age of the patient, birthweight, current weight, ventilator settings preoperatively, previous courses of indomethacin, sex and preoperative creatinine, were not correlated with the dose of fentanyl equivalent used. Logistic regression did not show a relationship between any of the previously mentioned factors and receiving a fentanyl equivalent of >10.5 mcg kg(-1). The only factor associated with the total fentanyl equivalent dose (as a continuous variable) or receiving <10.5 mcg kg(-1) (as a dichotomous variable) was the identity of the anesthetist involved, P<0.001.

CONCLUSION

We conclude that the use of at least 10.5 mcg kg(-1) of fentanyl equivalent as a component of the anesthetic regimen for surgical closure of a PDA in premature infants, avoids an unstable postoperative respiratory course.

Outcome following surgical closure of patent ductus arteriosus in very low birth weight infants in neonatal intensive care unit

PURPOSE

The aims of this study were to determine the factors affecting the outcome of patent ductus arteriosus ligation in very low birth weight infants (VLBWI) and demonstrate the safety of PDA ligation in VLBWI performed in the neonatal intensive care unit (NICU).

MATERIALS AND METHODS

From October 1994 to July 2006, medical records of 94 VLBWI weighing <1,500 g who underwent PDA ligation in the NICU of Samsung Medical Center were reviewed retrospectively. Factors affecting the final outcome of PDA ligation were evaluated by dividing the infants into 3 groups according to mortality and major morbidities as follows: mortality group (Mo), major morbidity group (Mb), and no major morbidity group (NM).

RESULTS

In the Mo group, birth weight was significantly lower and the preoperative mean FiO2 and mean dopamine dose were significantly higher than those in the other 2 groups. There was no significant difference in gestational age, incidence of RDS, number of courses of indomethacin, surgery-related factors, including weight and age at surgery, perioperative vital signs, and complications after surgery between the 3 groups. During surgery in the NICU, there were no significant hemodynamic instability or serious acute complications.

CONCLUSION

The factors affecting the outcome of surgery in VLBWI are not the factors related to surgery but the preoperative conditions related to the underlying prematurity. PDA ligation of VLBWI performed in the NICU is safe without serious complications.

Achieving positive protein balance in the immediate postoperative period in neonates undergoing abdominal surgery

OBJECTIVES

To determine whether neonates undergoing major abdominal surgical procedures in the first day of life could achieve a positive protein balance without protein toxicity in the immediate perioperative period by using parenteral amino acids and fentanyl analgesia.

STUDY DESIGN

Newborns undergoing major surgery for gastroschisis in the first 24 hours of life (n = 13) were alternately allocated to immediate postoperative parenteral administration of 1.5 g/kg(-1)/day(-1) versus 2.5 g/kg(-1)/day(-1) amino acids. Protein balance was determined at 1.6 to 2.6 days postoperatively with both nitrogen balance and leucine stable isotope methodology. Statistical analyses were conducted with the unpaired t test and linear regression.

RESULTS

Protein balance was significantly different in the 2 groups with both nitrogen balance and leucine stable isotope methodology. There was no evidence of protein toxicity as determined with blood urea nitrogen, creatinine, and ammonia concentrations.

CONCLUSIONS

Neonates undergoing the metabolic stress of abdominal surgery shortly after birth are able to achieve a net positive protein balance with parenteral amino acid administration without evidence of protein intolerance.

Cysteine, cystine or N-acetylcysteine supplementation in parenterally fed neonates

BACKGROUND

L-cysteine is thought to be a conditionally essential (i.e., essential under certain conditions) amino acid for neonates. It is a precursor of glutathione, an antioxidant that may reduce oxidation injury. The addition of cysteine to parenteral nutrition (PN) allows for the reduction of the amount of methionine in PN, thereby limiting hepatotoxicity, and acidifies the solution, thereby increasing calcium and phosphate solubility, and potentially improving bone mineralization.

OBJECTIVES

To determine the effects of supplementing parenteral nutrition with cysteine, cystine or its precursor N-acetylcysteine on neonatal growth and short and long-term outcomes.

SEARCH STRATEGY

The standard search method of the Cochrane Neonatal Review Group was used. MEDLINE (1966-December 2005), EMBASE (1974-December 2005), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2006) and recent abstracts (until December 2005) from the Society for Pediatric Research/American Pediatric Society, Eastern Society for Pediatric Research, and Society for Parenteral and Enteral Nutrition were searched.

SELECTION CRITERIA

All randomized (RCTs) and quasi-randomized trials that examined the effects of cysteine, cystine or N-acetylcysteine supplementation of neonatal PN were reviewed. Predetermined outcome variables included growth, nitrogen retention, mortality, morbidity secondary to oxidation injury, bone accretion, acidosis, liver disease, and cysteine levels.

DATA COLLECTION AND ANALYSIS

The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used. Statistical analysis included relative risk, risk difference, and weighted mean difference (WMD).

MAIN RESULTS

Six trials fulfilled entry criteria. The majority of patients in these trials were preterm. Five small trials evaluated short-term cysteine supplementation of cysteine-free PN. One large multicenter RCT evaluated short-term N-acetylcysteine supplementation of cysteine-containing PN in extremely low birth weight infants (< or = 1000 grams).

PRIMARY OUTCOMES

Growth was not significantly affected by cysteine supplementation (evaluated in one quasi-randomized trial) or by N-acetylcysteine supplementation (evaluated in one RCT). Nitrogen retention was significantly increased by cysteine supplementation (studied in four trials) (WMD 31.8 mg/kg/day, 95% confidence interval +8.2, +55.4, n = 95, including 73 preterm infants).

SECONDARY OUTCOMES

Plasma levels of cysteine were significantly increased by cysteine supplementation but not by N-acetylcysteine supplementation. N-acetylcysteine supplementation did not significantly affect the risks of death by 36 postmenstrual weeks, bronchopulmonary dysplasia (BPD), death or BPD, retinopathy of prematurity (ROP), severe ROP, necrotizing enterocolitis requiring surgery, periventricular leukomalacia, intraventricular hemorrhage (IVH), or severe IVH. No data were available on other outcomes.

AUTHORS' CONCLUSIONS

Available evidence from RCTs shows that routine short-term cysteine chloride supplementation of cysteine-free PN in preterm infants improves nitrogen balance.However, there is insufficient evidence to assess the risks of cysteine supplementation, especially regarding metabolic acidosis, which has been reported during the first two weeks of cysteine chloride administration. Available evidence from a large RCT trial does not support routine N-acetylcysteine supplementation of cysteine-containing PN in extremely low birth weight infants. A large RCT would be required to assess whether routine prolonged cysteine supplementation of cysteine-free PN affects growth and short and long-term neonatal outcomes in very low birth weight infants.

Effective and efficient nutritional support for the injured child

This article discusses the critical points in nutritional support of the injured child. Each applies currently understood basic science information to practical bedside care.