Komal Kamra

Ketamine does not increase pulmonary vascular resistance in children with pulmonary hypertension undergoing sevoflurane anesthesia and spontaneous ventilation.

BACKGROUND:The use of ketamine in children with increased pulmonary vascular resistance is controversial. In this prospective, open label study, we evaluated the hemodynamic responses to ketamine in children with pulmonary hypertension (mean pulmonary artery pressure >25 mm Hg). METHODS:Children aged 3 mo to 18 yr with pulmonary hypertension, who were scheduled for cardiac catheterization with general anesthesia, were studied. Patients were anesthetized with sevoflurane (1 minimum alveolar anesthetic concentration [MAC]) in air while breathing spontaneously via a facemask. After baseline catheterization measurements, sevoflurane was reduced (0.5 MAC) and ketamine (2 mg/kg IV over 5 min) was administered, followed by a ketamine infusion (10 &mgr;g · kg−1 · min−1). Catheterization measurements were repeated at 5, 10, and 15 min after completion of ketamine load. Data at various time points were compared (ANOVA, P < 0.05). RESULTS:Fifteen patients (age 147, 108 mo; median, interquartile range) were studied. Diagnoses included idiopathic pulmonary arterial hypertension (5), congenital heart disease (9), and diaphragmatic hernia (1). At baseline, median (interquartile range) baseline pulmonary vascular resistance index was 11.3 (8.2) Wood units; 33% of patients had suprasystemic mean pulmonary artery pressures. Heart rate (99, 94 bpm; P = 0.016) and Pao2 (95, 104 mm Hg; P = 007) changed after ketamine administration (baseline, 15 min after ketamine; P value). There were no significant differences in mean systemic arterial blood pressure, mean pulmonary artery pressure, systemic or pulmonary vascular resistance index, cardiac index, arterial pH, or Paco2. CONCLUSIONS:In the presence of sevoflurane, ketamine did not increase pulmonary vascular resistance in spontaneously breathing children with severe pulmonary hypertension.

Perioperative complications in children with pulmonary hypertension undergoing general anesthesia with ketamine

Background:  Pulmonary arterial hypertension (PAH) is associated with significant perioperative risk for major complications in children, including pulmonary hypertensive crisis and cardiac arrest. Uncertainty remains about the safety of ketamine anesthesia in this patient population.

Postoperative Analgesia After Spinal Blockade in Infants and Children Undergoing Cardiac Surgery

The aim of this prospective, randomized, controlled clinical trial was to define the opioid analgesic requirement after a remifentanil (REMI)-based anesthetic with spinal anesthetic blockade (SAB+REMI) or without (REMI) spinal blockade for open-heart surgery in children. We enrolled 45 patients who were candidates for tracheal extubation in the operating room after cardiac surgery. Exclusion criteria included age <3 mo and >6 yr, pulmonary hypertension, congestive heart failure, contraindication to SAB, and failure to obtain informed consent. All patients had an inhaled induction with sevoflurane and maintenance of anesthesia with REMI and isoflurane (0.3% end-tidal). In addition, patients assigned to the SAB+REMI group received SAB with tetracaine (0.5–2.0 mg/kg) and morphine (7 &mgr;g/kg). After tracheal extubation in the operating room, patients received fentanyl 0.3 &mgr;g/kg IV every 10 min by patient-controlled analgesia for pain score = 4. Pain scores and fentanyl doses were recorded every hour for 24 h or until the patient was ready for discharge from the intensive care unit. Patients in the SAB+REMI group had significantly lower pain scores (P = 0.046 for the first 8 h; P =0.05 for 24 h) and received less IV fentanyl (P = 0.003 for the first 8 h; P = 0.004 for 24 h) than those in the REMI group. There were no intergroup differences in adverse effects, including hypotension, bradycardia, highest PaCO2, lowest pH, episodes of oxygen desaturation, pruritus, and vomiting.

A randomized, controlled trial of aprotinin in neonates undergoing open‐heart surgery

Background:  Neonates undergoing open‐heart surgery are especially at risk for massive bleeding and pronounced inflammation. The efficacy of aprotinin, a serine protease inhibitor, at ameliorating these adverse effects of cardiopulmonary bypass has not been clearly demonstrated in neonates.

Role of transesophageal echocardiography in the management of pediatric patients with congenital heart disease.

Transesophageal echocardiography (TEE) has become a critical diagnostic and perioperative management tool for patients with congenital heart disease (CHD) undergoing cardiac and noncardiac surgical procedures. This review highlights the role of TEE in routine management of pediatric cardiac patient population with focus on indications, views, applications and technological advances.

Esophageal saturation during antegrade cerebral perfusion: a preliminary report using visible light spectroscopy

Background:  Visible light spectroscopy (VLS) is newer technology that measures real‐time tissue oxygenation. It has been validated in detecting mucosal ischemia in adults. During complex neonatal heart surgery, antegrade cerebral perfusion (ACP) maintains cerebral saturation. Whether ACP maintains peripheral tissue perfusion in humans is not known.

Surgical Algorithm And Results For Repair Of Pulmonary Atresia With Ventricular Septal Defect And Major Aortopulmonary Collaterals

Objective Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries is a complex and heterogeneous form of congenital heart disease. There is a controversy regarding the optimal treatment of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. The purpose of this study was to summarize our algorithm and surgical results for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. Methods This was a retrospective review of 307 patients undergoing primary surgical treatment of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. Excluded from this analysis were patients who had undergone prior surgical treatment at another institution and patients with single ventricle and major aortopulmonary collateral arteries. There were 3 surgical pathways, including midline unifocalization (n = 241), creation of an aortopulmonary window (n = 46), and other (n = 20). Results For the 241 patients who underwent midline unifocalization, 204 (85.4%) had a single‐stage complete repair. There were 37 patients who underwent a midline unifocalization and central shunt, and 24 have subsequently undergone complete repair. Forty‐six patients underwent an aortopulmonary window, of whom 36 have subsequently had a complete repair. There were 20 patients who had complex anatomy and underwent procedures other than described, and14 have subsequently undergone complete repair. Thus, for the patients currently eligible, 280 (93.0%) have achieved complete repair. For the 204 patients who had a single‐stage complete repair, the mean right ventricle to aortic pressure ratio was 0.36 ± 0.09. Seventy‐six patients underwent a staged repair, and the mean right ventricle to aortic pressure ratio was 0.40 ± 0.09 (P < .05 compared with single‐stage repair). There were 3 (1.5%) early and 8 (4.0%) late deaths for the single‐stage complete repair cohort versus 4 (4.0%) early and 15 (14.9%) late deaths for all other procedures (P < .01). Conclusions The data demonstrate that more than 90% of patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries achieved complete repair. The overall mortality was significantly lower in the subgroup of patients who underwent single‐stage complete repair.

Central venous catheter placement in children: ‘How good is good enough?’

In this issue of Pediatric Anesthesia, Malbezin et al. describe their 22-year experience of placing percutaneous central venous catheters (CVCs) in children. Their report is somewhat unique in that tunneled catheters were, in many cases, placed under general anesthesia by members of the anesthesia service for purposes other than for immediate use during surgery. In the United States, tunneled CVCs are usually placed by pediatric surgeons. The ASA guidelines, to which the authors refer, specifically exclude the placement of tunneled catheters (1). Nevertheless, Malbezin et al. are to be congratulated for developing a novel and practical service at their institution. Many of the advantages and disadvantages of their methodology and selection site for central venous catheter insertion may be applied more broadly to placement of nontunneled CVCs by pediatric anesthesiologists and intensivists elsewhere. Percutaneous CVCs are useful in infants and children for infusion of drugs, blood products, and parental nutrition. CVCs also facilitate central venous pressure monitoring and phlebotomy for blood testing, including venous blood gas tension analysis (1). Specialized, larger catheters are also used for dialysis, including hemodialysis and continuous venovenous hemofiltration with dialysis. Accordingly, CVCs are often placed by anesthesiologists for use during and after major surgery and by pediatric intensivists for use in critically ill patients. Usual sites of insertion of CVCs include the internal jugular, subclavian, and femoral veins. Each of these sites presents relative advantages, including ease of insertion; the internal jugular vein may be most accessible to the anesthesiologist prior to surgery, whereas the femoral vein may be more convenient in the pediatric intensive care unit, especially during resuscitation. Each site also has unique disadvantages, including complications during placement and the risk of infection. The latter may not be highest on the list of considerations among anesthesiologists, but use and maintenance of CVCs placed in the operating room and remaining in situ for postoperative care should be considered by anesthesiologists prior to catheter insertion. Such consideration may influence the type of catheter used (e.g., size and number of lumens) and site of insertion (e.g., subclavian versus internal jugular). Problems associated with CVC insertion include those that are immediately recognizable and intermediate-tolong-term complications caused by indwelling catheters. During attempted placement, inadvertent arterial puncture may lead to hematoma formation with compression of adjacent structures, hemothorax, emboli, and arterial injury, especially when the artery is actually dilated and/or cannulated. In the latter case, continuous pressure applied to the puncture site for several minutes usually prevents hemorrhagic sequelae in children with normal coagulation function. While arterial or venous bleeding may occur at any site, compression may be most difficult over the subclavian area. Hemothorax and pneumothorax are more commonly associated with attempted subclavian venous catheterization, with a risk of approximately 2% (2). A meta-analysis of studies in adults showed no difference in bacterial colonization or CABSI rates between internal jugular, subclavian, and femoral venous CVCs (3). It might be reasonable to assume that the neck and inguinal regions are especially prone to CVC contamination in infants and young children, but data from pediatric studies do not confirm this (4,5). A randomized, controlled study in adults determined that venous thrombotic complications were more likely to occur with femoral compared with subclavian venous CVCs (6). The recent ASA guidelines state, ‘Catheter insertion site selection should be based on clinical need. An insertion site should be selected that is not contaminated or potentially contaminated (e.g., burned or infected skin, inguinal area, adjacent to tracheostomy or open surgical wound). In adults, selection of an upper body insertion site should be considered to minimize the risk of infection’ (1). No compelling data exist with respect to this issue in infants and children. In the United States, a number of precautions designed to minimize the incidence of CABSIs have become incorporated into routine practice. These include use of aseptic technique, including hand-washing, use of cap, mask, sterile gloves, gown, and large drape (‘maximal barrier precautions’). The skin should be prepped with chlorhexidine solution (unless contraindicated). The site of CVC insertion must be determined based on several considerations, including identifying an area of noncontaminated or burned skin, provider experience, and clinical circumstances (e.g., convenience and familiarity of the internal jugular vein for anesthesia providers; consideration of use of the subclavian vein for longer term use; and use of the femoral vein during cardiopulmonary resuscitation). Transparent, occlusive dressings should be used in all cases, and catheter injections sites should