Propofol-ketamine mixture for anesthesia in pediatric patients undergoing cardiac catheterization

OBJECTIVE: To evaluate the safety of a propofol-ketamine mixture to induce and maintain anesthesia in spontaneously breathing pediatric patents during cardiac catheterization. DESIGN: Prospective clinical study. SETTING: Departments of Cardiothoracic Surgery, Anesthesiology, and Pediatric Anesthesiology in a university hospital. PARTICIPANTS: Forty-five children aged 6 months to 16 years with ASA grade II to III undergoing cardiac catheterization. INTERVENTIONS: Continuous intravenous infusion of a mixture of propofol (4 mg/mL) and ketamine (2 mg/mL) with spontaneous ventilation. The infusion rate was changed and additional boluses of propofol or/and ketamine were given as needed. Hemodynamic, respiratory, and other variables were recorded during the procedure and recovery. RESULTS: Mean dose of ketamine was 26 +/- 8.3 microg/kg/min and of propofol, 68.3 +/- 21.7 microg/kg/min. Changes in heart rate and mean arterial pressure of more than 20% from baseline were observed in 4 and 5 patients, respectively. A transient reduction in oxygen saturation because of hypoventilation was observed in 3 patients and responded to oxygen administration and manual assisted ventilation. No other complications were observed. CONCLUSIONS: The propofol-ketamine mixture is a safe, practical alternative for general anesthesia in pediatric patients undergoing cardiac catheterization.     

Initial experience with dexmedetomidine for diagnostic and interventional cardiac catheterization in children

BACKGROUND: Children undergoing diagnostic and interventional cardiac catheterization require deep sedation or general anesthesia (GA). Dexmedetomidine, a selective alpha-2 adrenergic agonist, has sedative, analgesic and anxiolytic properties without respiratory depression. These characteristics make it potentially suitable as a sedative agent during diagnostic procedures in children. We report our experience using dexmedetomidine in 20 children aged 3 months to 10 years undergoing cardiac catheterization. METHODS: Following a midazolam premedication, intravenous access was secured facilitated by the inhalation of sevoflurane in oxygen. A loading dose of 1 microg x kg(-1) dexmedetomidine was administered over 10 min followed by an initial infusion rate of 1 microg x kg(-1) x h(-1). Nasal cannulae were applied, allowing endtidal CO2 monitoring with the patients breathing spontaneously. Hemodynamic parameters, Bispectral Index Score (BIS) and sedation score were measured every 5 min. Patient movement or evidence of inadequate sedation were treated with propofol (1 mg x kg(-1)). The dexmedetomidine infusion rate was titrated to the level of sedation to a maximum of 2 microg x kg(-1) x h(-1) to maintain a sedation score of 4-5 and a BIS value <80. RESULTS: Five patients (25%) had some movement on local infiltration or groin vessel access. This did not necessitate restraint or result in difficulty securing vascular access. No patients failed sedation that required the addition of another sedative agent or conversion to GA; eight patients were sedated with dexmedetomidine alone; however, 12 (60%) patients did receive a propofol bolus at some time during the procedure due to movement, increasing BIS value or in anticipation of stimulation. There were no incidences of airway obstruction or respiratory depression. In all cases the heart rate and blood pressure remained within 20% of baseline. No patient required treatment for profound bradycardia or hypotension. The average infusion rate for dexmedetomidine following the loading dose was 1.15 (+/-0.29)microg x kg(-1) x h(-1) (range 0.6-2.0 microg x kg(-1) x h(-1)). CONCLUSIONS: This initial experience showed dexmedetomidine, with or without the addition of propofol, may be a suitable alternative for sedation in spontaneously breathing patients undergoing cardiac catheterization.     

Spinal anesthesia for noncardiac surgery in infants with congenital heart diseases

Objective/Aim: To compare hemodynamic parameters in infants with congenital heart disease (CHD) undergoing noncardiac surgery (NCS) under awake spinal anesthesia (SA) with controls without CHD also undergoing SA. Background: NCS poses a twofold higher mortality risk in infants with CHD. SA might be a good alternative to general anesthesia (GA) in this setting. Methods: The files of 84 infants were reviewed; 42 had CHD and 42 were controls without CHD. Primary outcome measures were percent decrease in mean arterial pressure (%MAP_decrease) and heart rate (%HR_decrease) from baseline to the lowest intraoperative value. One‐way analysis of variance (anova ), anova with repeated measures, Pearson chi‐square test, Fisher’s exact test, and Pearson correlation were used for statistical analysis. Time to discharge was analyzed with the nonparametric Mann–Whitney U‐test. Results: There were no significant between‐group differences in %MAP_decrease and %HR_decrease; no significant associations and correlations between %MAP_decrease or %HR_decrease and other variables; and no correlation between %MAP_decrease and %HR_decrease. A %MAP_decrease of >20% was documented in 11 patients with CHD (26.2%) and 10 controls (23.8%); a lowest intraoperative HR of <100 b·min^?1 was recorded in two study patients (4.8%) and four controls (9.5%) (P = NS for both). There were no cases of high SA or conversion to GA and no need for mechanical ventilation or inotropic support intra/postoperatively. Conclusions: These preliminary findings show that hemodynamic parameters in infants with CHD undergoing NCS under awake SA are not different from controls without CHD and that SA appears to be safe in infants with CHD.     

Dexmedetomidine/ketamine for diagnostic cardiac catheterization in a child with idiopathic pulmonary hypertension

The use of a combination of dexmedetomidine and ketamine to provide procedural sedation in a 12-year old boy with a diagnosis of idopathic pulmonary hypertension and a behavioral disorder, undergoing diagnostic cardiac catheterization, is presented. Following a loading dose of ketamine one mg/kg and dexmedetomidine one mcg/kg, an infusion of dexmedetomidine at one mcg/kg/hr was used with the patient breathing spontaneously. Stable hemodynamics were observed throughout the procedure and pulmonary vascular resistance was measured under three conditions. The dexmedetomidine infusion was continued for two hours post-catheterization, facilitating a smooth emergence.     

Combined spinal-epidural anesthesia in major abdominal surgery in high-risk neonates and infants

BACKGROUND: Combined spinal-epidural anesthesia (CSE-A) is reportedly safe and effective for the pediatric population in infraumbilical surgery. Our main purpose was to describe our experience of this technique in neonates and infants undergoing elective major upper abdominal surgery. METHODS: Spinal anesthesia was performed in 28 neonates and infants with isobaric bupivacaine 0.5%, 1 mg.kg(-1) followed by placement of a caudal epidural catheter to thoracic spinal segments. The catheter tip position was confirmed radiographically. Respiratory and hemodynamic data were collected before and after the CSE-A and throughout the operation, as a measure of anesthetic effectiveness. Complications related to the anesthesia technique were collected as a measure of the anesthetic technique safety. RESULTS: Satisfactory surgical anesthesia was achieved in 24 neonates and infants, four patients were converted to general anesthesia. Respiratory and hemodynamic variables did not change significantly during surgery, compared with baseline values: oxygen saturation (P = 0.07), systolic and diastolic blood pressures (P = 0.143, P = 0.198 respectively), heart rate (P = 0.080) and respiratory rate (P = 0.127). However, twenty infants were fussy during the surgical procedures and were calmed with intravenous midazolam; our patients required oxygen supplementation and transient manual ventilation intraoperatively. CONCLUSIONS: Combined spinal-epidural anesthesia could be considered as an effective anesthetic technique for elective major upper abdominal surgery in awake or sedated neonates and infants, and could be used cautiously by a pediatric anesthesiologist as an alternate to general anesthesia in high-risk neonates and infants undergoing upper gastrointestinal surgery.     

Spinal anesthesia for arthroscopic knee surgery

BACKGROUND AND OBJECTIVE: The purpose of the study was to compare the effects of adding 50 microg of morphine, 25 microg of fentanyl or saline to 6 mg of hyperbaric bupivacaine on postoperative analgesia and time to urination in patients undergoing arthroscopic knee surgery under spinal anesthesia. METHODS: The study was designed in a prospective, randomized, double-blinded and placebo-controlled manner. Sixty ASA I-II patients were randomized into the following three groups: Group BM: 6 mg of bupivacaine and 50 microg of morphine, Group BF: 6 mg of bupivacaine and 25 microg of fentanyl, and Group BS: 6 mg of bupivacaine and saline. Selective spinal anesthesia was performed in a lateral decubitus position, with the operative knee dependent for 10 min. RESULTS: In all groups satisfactory anesthesia was provided during the operation. There was a statistically significant difference between all the groups in times to voiding [Group BM 422 +/- 161 min; Group BF 244 +/- 163 min; Group BS 183 +/- 54 min (mean +/- SD)]. The incidence of pruritus was significantly greater in Group BM (80%) and BF (65%) in comparison with Group BS (no pruritus) (P < 0.05). The incidence of nausea was significantly increased in Group BM (35%) in comparison with Group BF (10%) and Group BS (P < 0.05). Analgesic consumption was significantly greater in Group BS in comparison with Groups BM and BF (P < 0.01). CONCLUSIONS: We conclude that during spinal anesthesia even mini-dose intrathecal morphine is not acceptable for outpatient surgery due to side-effects, especially severely prolonged time to urination.     

Spinal anesthesia in neonates and infants - a single-center experience of 505 cases

BACKGROUND: Our aim was to assess the safety and efficacy of spinal anesthesia (SA) in newborns and infants undergoing surgery appropriate for this technique. METHODS: The files of 505 patients who underwent surgery under spinal anesthesia since 1998 at a major tertiary hospital in Israel were analyzed retrospectively. SA was performed with bupivacaine 5 mgxml(-1) by attending pediatric anesthesiologists or an anesthesia resident. Demographic data, prematurity history, comorbidities, technical data, cardiovascular stability, complications and supplementary drugs were documented. The surgeon assessed the quality of anesthesia at the end of surgery. RESULTS: Appropriate SA was achieved in 95.3% of cases; in 69.9% at the first attempt. The mean number of attempts per patient was 1.41 and mean dose of bupivacaine was 0.66 +/- 0.16 mgxkg(-1). Intravenous sedation, usually with midazolam (dose 0.1-0.2 mgxkg(-1)) was required in 28.1% of children because of crying/restlessness. Intraoperative conversion to general anesthesia was necessary in five patients (1.04%). The main side effect was bradycardia (<100 bxmin(-1)) without desaturation which occurred in nine patients (1.8%). In three patients (0.62%), high spinal block occurred without bradycardia and hypotension. None of the patients had postoperative meningitis. CONCLUSIONS: SA is safe and effective in newborns and infants undergoing low abdominal, perineal and orthopedic surgery. In order to save time, our advice is to attempt SA after the surgeon is scrubbed, and minimize surgical teaching activity. The need to deal with a small and sometimes sick patient independent of the type of anesthesia requires the presence of an experienced pediatric anesthesiologist.     

Anesthesia and the pediatric cardiac catheterization suite: a review

Advances in technology over the last couple of decades have caused a shift in pediatric cardiac catheterization from a primary focus on diagnostics to innovative therapeutic interventions. These improvements allow patients a wider range of nonsurgical options for treatment of congenital heart disease. However, these therapeutic modalities can entail higher risk in an already complex patient population, compounded by the added challenges inherent to the environment of the cardiac catheterization suite. Anesthesiologists caring for children with congenital heart disease must understand not only the pathophysiology of the disease but also the effects the anesthetics and interventions have on the patient in order to provide a safe perioperative course. It is the aim of this article to review the latest catheterization modalities offered to patients with congenital heart disease, describe the unique challenges presented in the cardiac catheterization suite, list the most common complications encountered during catheterization and finally, to review the literature regarding different anesthetic drugs used in the catheterization lab.     

Anesthetic considerations for magnetic resonance imaging‐guided right‐heart catheterization in pediatric patients: A single institution experience

Cardiac catheterization is an integral part of medical management for pediatric patients with congenital heart disease. Owing to age and lack of cooperation in children who need this procedure, general anesthesia is typically required. These patients have increased anesthesia risk secondary to cardiac pathology. Furthermore, multiple catheterization procedures result in exposure to harmful ionizing radiation. Magnetic resonance imaging‐guided right‐heart catheterization offers decreased radiation exposure and diagnostic imaging benefits over traditional fluoroscopy but potentially increases anesthetic complexity and risk. We describe our early experience with anesthetic techniques and challenges for pediatric magnetic resonance imaging‐guided right‐heart catheterization.     

Spinal anesthesia in infants with ventriculoperitoneal shunt: report of five cases and review of literature

We describe five cases of children with ventriculoperitoneal shunt who underwent abdominal and perineal procedures under spinal anesthesia. Four of them had been born prematurely, and all had suffered from severe neonatal complications. All of our patients suffered from severe respiratory impairment, that had required mechanical ventilation, and three of them suffered additionally from apnea of prematurity. Four patients had ventriculoperitoneal shunt inserted because of obstructive hydrocephalus and one because of congenital central nervous system anomalies. Two underwent subsequently shunt revision. The benefits of spinal anesthesia in this high-risk population are described. The risks of spinal anesthesia in the presence of a ventricular shunt device, especially infection and dural leakage, are discussed, and the literature about this topic briefly reviewed.     

Remifentanil infusion for cardiac catheterization in children with congenital heart disease

BACKGROUND: Cardiac catheterization of children with congenital heart disease is increasingly being performed under general anesthesia. Haemodynamic stability during anesthesia and fast and adequate recovery after the procedure is crucial in these patients. We performed a pilot study to evaluate hemodynamic stability when using remifentanil for anesthesia during cardiac catheterization. We also evaluated extubation times and recovery characteristics. METHODS: In a randomized, prospective, double-blind study 30 children (aged 1.5-20 months) received a continuous infusion of either 0.2 (group 0.2) or 0.3 microg/kg/min remifentanil (group 0.3) as part of a balanced anesthesia with 0.6 MAC sevoflurane. Heart rate, noninvasive arterial blood pressure, end tidal CO2 and pulse oxymetry were monitored throughout the procedure. Extubation times were noted, and recovery from anesthesia was evaluated using Aldrete scores. RESULTS: : Haemodynamic response to intubation was well blunted in both groups. No significant changes in hemodynamic variables were noted from induction of anesthesia until 10 min after intubation. From then on there was a decrease in HR and systolic arterial pressure, which remained significant throughout the procedure in both groups. Extubation times were similar in both groups: 7.3 min (2,1) in group 0.2 vs. 6.6 min (2,1) in group 0.3 (NS). The number of patients with an Aldrete score of nine or more was 14 (group 0.2) vs. 15 (group 0.3), 10 min after extubation (NS). CONCLUSION: Both dose regimens of remifentanil provided stable hemodynamic conditions during anesthesia for cardiac catheterization of children with congenital heart disease and allowed for rapid and adequate recovery.     

Spinal anesthesia for a patient with type I sialidosis undergoing abdominal surgery

Type I and II sialidosis are autosomal recessively inherited glycoprotein storage disorders. Until now, there has been no published reports of patients with these conditions requiring anesthesia. We present the case of a 31-year-old male afflicted with type I sialidosis who underwent a surgical jejunostomy. Regional (spinal) anesthesia was carried out uneventfully. We discuss the anesthetic challenges posed by patients with type I and II sialidosis. Airway assessment and management is particularly crucial.