Anesthetic management of children with pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is associated with significant perioperative risk for major complications, including pulmonary hypertensive crisis and cardiac arrest. Several mechanisms of hemodynamic deterioration, including acute increases in pulmonary vascular resistance (PVR), alterations of ventricular contractility and function and coronary hypoperfusion can contribute to morbidity. Anesthetic drugs exert a variety of effects on PVR, some of which are beneficial and some undesirable. The goals of balanced and cautious anesthetic management are to provide adequate anesthesia and analgesia for the surgical procedure while minimizing increases in PVR and depression of myocardial function. The development of specific pulmonary vasodilators has led to significant advances in medical therapy of PAH that can be incorporated in anesthetic management. It is important that anesthesiologists caring for children with PAH be aware of the increased risk, understand the pathophysiology of PAH, form an appropriate anesthetic management plan and be prepared to treat a pulmonary hypertensive crisis.     

Laryngeal mask airway insertion in children: comparison between rotational, lateral and standard technique

Background:  The purpose of the study was to compare the success and ease of insertion of three techniques of laryngeal mask airway (LMA) insertion; the standard Brain technique, a lateral technique with cuff partially inflated and a rotational technique with cuff partially inflated.
Methods:  One hundred and sixty-eight ASA I and II children aged 6 months to 6 years undergoing short elective surgical procedures lasting 40–60 min were included in the study. A standard anesthesia protocol was followed for all patients. Patients were randomly allocated into one of the three groups i.e. standard (S), rotational (R) and lateral (L). The primary outcome measure of the study was success rate at the first attempt using three techniques of LMA insertion. Secondary outcomes measures studied were overall success rate, time before successful LMA insertion, complications and maneuvers used to relieve airway obstruction.
Results:  Successful insertion at the first attempt was significantly higher in group R (96%) compared with group L (84%) and group S (80%) ( P  =   0.03). Overall success rate (i.e. successful insertion with two attempts) was 100% for group R, 93% for group L and 87% for group S ( P  =   0.03). Time for successful insertion was significantly lower in group R compared with group L and S ( P  <   0.001). The incidence of complications was lower in group R.
Conclusions:  A rotational technique with partially inflated cuff is associated with the highest success rate of insertion and lowest incidence of complications and could be the technique of first choice for LMA insertion in pediatric patients.     

Efficacy of ketamine and midazolam as co-induction agents with propofol for laryngeal mask insertion in children

Objectives: Use of midazolam and ketamine lowers the induction dose of propofol (co‐induction) producing hemodynamic stability. Background: Large doses of propofol needed for induction and laryngeal mask (LM) insertion in children may be associated with hemodynamic and respiratory effects. Co‐induction has the advantage of reducing dose and therefore maintaining hemodynamic stability. Aim: To examine the effect of co‐induction on hemodynamics, LM insertion and recovery in children. Methods/Materials: A prospective, randomized, double‐blind, controlled study was conducted in 60 ASA I/II children, age 1–8 years. Normal saline, ketamine 0.5 mg·kg^?1, midazolam 0.05 mg·kg^?1 were administered in groups P (propofol), PK (propofol–ketamine) and PM (propofol–midazolam), respectively, 2 min prior to the administration of the induction dose of propofol. Propofol 3.5 mg·kg^?1 (group P) or 2.5 mg·kg^?1 (groups PK and PM) was used for induction, LM inserted 30 s later and insertion conditions assessed. Heart rate and blood pressure were recorded immediately after propofol bolus, then every min till 2 min after LMA insertion. Recovery was assessed using Steward’s Score. Result: In group P, systolic blood pressure (SBP) showed a significantly greater decrease compared to group PK and group PM (P < 0.005). Only 5% of patients in groups PK and PM showed >20% fall in SBP compared to 89% in group P (P < 0.005). More children in groups PK and PM had acceptable conditions for LM insertion compared to group P (P < 0.05). The time to achieve Steward Score of 6 was longer in groups PK and PM compared to group P (P < 0.005). Conclusion: In children, the combination of propofol with ketamine or midazolam produces stable hemodynamics and improved LM insertion conditions but is associated with delayed recovery.     

The Callender modification of the Macintosh laryngoscope blade reduces the risk of tooth-blade contact in children

Background: Dental injury is well recognized as a potential complication of laryngoscopy and tracheal intubation. The flange of the Macintosh blade may contact teeth during laryngoscopy causing damage. The Callander modification of the Macintosh blade (Callander blade) with a shortened heel at the proximal end has been shown to increase the blade–tooth distance and reduce contact rates in adults. Aim: This study was designed to evaluate the effectiveness of the Callander blade on reducing dental contact in children. Methods: One hundred children, aged 4–14 years, scheduled for general anesthesia requiring endotracheal intubation were studied prospectively. The children were preoperatively evaluated for Mallampati score and dental defects, looseness, and avulsions. Following induction of anesthesia, laryngoscopy was performed twice on each child in succession, once with a standard Macintosh blade and once with a Callander blade of the same size in a random order. The blade–tooth distance and contact rate were compared between the two blades. Results: With the Callander blade, the blade–tooth distance was greater than with the Macintosh (1.78 ± 1.77 vs 0.28 ± 0.76 mm, P = 0.001). The frequency of direct contact was less with the Callander blade than it was with the Macintosh blade (33% vs 86%, respectively, P = 0.008). However, difficult laryngoscopy rate did not differ between the blades. Tracheal intubation was successful in all children and there was no dental injury. Conclusion: Our findings suggest that the Callander blade decreases the risk for dental injury and provides tracheal intubating conditions in children with normal airways similar to those obtained with a traditional Macintosh blade.     

Malignant breast cancer in children: a review of 75 patients

OBJECTIVE: To determine incidence trends and outcomes for pediatric patients with malignant breast disease. METHODS: The Surveillance, Epidemiology, and End Results registry was examined for all females 19 years of age and younger diagnosed with a malignant breast tumor between 1973 and 2004. RESULTS: A total of 75 patients with malignant breast tumors were identified. Overall, 14.5% of patients had in situ tumors, and 85.5% had invasive disease. Tumors were classified as being either carcinomas (n = 41, 54.7%) or sarcomas (n = 34, 45.3%). The majority of sarcomatous lesions were phyllodes tumors (n = 29, 85.5%), whereas most carcinomas were of a ductal etiology (n = 19, 46.3%). The age-adjusted incidence of all malignant pediatric breast tumors in 2003 was 0.08 cases per 100,000 people (0.03 carcinoma and 0.06 sarcoma cases per 100,000 people). In the carcinoma group, regionally advanced disease was present in 11 patients (26.8%), whereas only 3 patients (7.3%) presented with metastatic disease. All patients with sarcomatous tumors presented with localized disease. Adjuvant radiation therapy was administered in only 9.8% of carcinomas and 8.8% of sarcomas, and 85.4% of carcinoma patients and 97.1% of sarcoma patients underwent surgical resection for their primary disease. Subgroup analysis revealed 5- and 10-year survival rates of 89.6% for patients with sarcomatous tumors and 63.1% and 54.3% for carcinomas. CONCLUSIONS: Malignant pediatric breast malignancies remain relatively rare. The two most common histologies of breast neoplasms in children are malignant carcinomas followed by sarcomas. Although uncommon, malignant disease must be considered in the differential diagnosis of the pediatric patient with a breast mass.     

回收式自体输血在儿童先天性髋关节脱位手术中的应用

[目的]探讨儿童先天性髋关节脱位的股骨和骨盆联合手术中洗涤式自体血液回收的应用方法与前景。[方法]2003年8月~2005年12月,17例先天性髋关节脱位股骨和骨盆联合手术中,使用Cell Saver 5血液回收系统行术中的血液回收。观察回输自体血液后的并发症发生情况,记录术中估计失血量、实际回收血量,以及回输血前后的Hb、Hct、P lt、PT、APTT、HR、BP、SPO2等的变化情况。[结果]17例患儿术中血液回收总量2 090 m l,平均每人(171±53)m l。其中4例出现一过性血红蛋白尿,其他无并发症。患者术前和术后24 h的Hb、Hct、HR比较差异有显著性意义(P<0.01);患者术前和术后24 h的P lt、PT、APTT、SPO2、BP比较差异无显著性意义(P>0.05)。[结论]儿童先天性髋关节脱位的股骨和骨盆联合手术中的血液回收是安全、有效的自体输血方式,明显节约异体血的用量,有效避免血液传播性疾病的发生。     

Titanium elastic nailing in femoral diaphyseal fractures of children in 6-16 years of age

Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.     

Effects of chlorpromazine as a systemic vasodilator during cardiopulmonary bypass in neonates

OBJECTIVES: Vasodilator use during cardiopulmonary bypass is important in pediatric cardiac surgery, but the full range of their effects on hemodynamics remains to be clarified. We studied the effects of chlorpromazine, a potent alpha-blocking agent, in neonates. METHODS: Subjects were 60 neonates undergoing arterial switch operations for complete transposition of the great arteries with an intact ventricular septum. Of these, 37 received 2.1 to 6.5 mg/kg of chlorpromazine during cardiopulmonary bypass (CPZ group) and 23 received no vasodilator (control group). We then compared hemodynamic parameters between groups during and early after surgery. RESULTS: The systemic vascular resistance index and mean arterial pressure during cardiopulmonary bypass were significantly lower in the CPZ group (p < 0.05), but systolic pressure 15 minutes after cessation of cardiopulmonary bypass did not differ between groups. The rise in peripheral temperature during rewarming after hypothermia was significantly higher and the acid-base status 40 minutes after cardiopulmonary bypass less acidotic in the CPZ group. Urine output during cardiopulmonary bypass was higher in the CPZ group. CONCLUSIONS: Chlorpromazine effectively counteracts systemic vasoconstriction induced by cardiopulmonary bypass without serious side effects in neonatal cardiac surgery.     

Reduction in acute rejections decreases chronic rejection graft failure in children: a report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS).

Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections.     

Premedication in children: a comparison of oral midazolam and oral clonidine

BACKGROUND: Oral premedication is widely used in pediatric anesthesia to reduce preoperative anxiety and ensure smooth induction. Midazolam is currently the most commonly used premedicant, but good results have also been reported with clonidine. The aim of the present study was to compare clinical effects of oral midazolam and oral clonidine. METHODS: We performed a prospective open study in 64 children who were randomly assigned to receive either oral midazolam 0.5 mg.kg (-1) (group M) or oral clonidine 4 microg.kg (-1) (group C) prior to mask induction. Drug acceptance, preoperative sedation and anxiolysis, quality of mask acceptance, recovery profile and parental satisfaction were evaluated. RESULTS: The taste of oral clonidine was judged as significantly better; 14% of children rejected oral midazolam. Onset of sedation was significantly faster after premedication with midazolam (30+/-13.1 min) than with clonidine (38.5+/-14.6 min), but level of sedation was significantly better after premedication with clonidine. Quality of mask induction was equally successful in both groups. A steal-induction was performed in 66% of patients of group C, but none in group M. We observed a trend towards an increased incidence of emergence agitation after premedication with midazolam. Parental satisfaction was significantly higher in group C. CONCLUSIONS: In this study, premedication with oral clonidine appeared to be superior to oral midazolam. Quality of mask acceptance was comparable between groups, but oral clonidine was better accepted by the child, produced more effective preoperative sedation, showed a trend towards better recovery from anesthesia and had a higher degree of parental satisfaction.