The ulnar artery: A site suitable for arterial cannulation in pediatric patients.

BACKGROUND: Historically, the ulnar artery has rarely been considered for arterial cannulation as it is less easily palpated than the radial artery. With the current routine use of ultrasound in pediatric patients, the ulnar is as accessible as the radial and could be viewed as an equivalent site for cannulation. AIMS: The purpose of this study was to compare ulnar and radial artery suitability for arterial cannulation in pediatric patients using 2-dimensional ultrasound. METHODS: We examined the ulnar and radial arteries of pediatric patients aged birth to 6 years who were scheduled to undergo general anesthesia. Following anesthesia induction, the investigators positioned the patient's wrist to 30-45 degrees of extension and obtained images of the ulnar and radial arteries in the transverse and longitudinal planes. Assessments of the arteries' anterior-posterior diameter, cross-sectional area and depth were made by visual inspection at the time of image acquisition and by electronic caliper measurement of recorded images. RESULTS: In 108 patients, mean anterior-posterior diameter of the ulnar artery was larger than the radial artery in the transverse view, longitudinal view, and cross-sectional area in 63.6%, 59.4%, and 60.4% of patients (p = .002, .004, and .006, respectively). Mean ulnar artery size was, on average, larger than the radial artery by 7.7%, 8.1%, and 12.9% in the transverse AP diameter, longitudinal AP diameter, and cross-sectional area (95% CI 3.1-12.4%; 3.2-13.0%; 4.4-21.5%). The investigator's visual evaluation of vessel size at the bedside showed substantial agreement with the measured cross-sectional area (linear-weighted kappa of 0.73). In a subset of 13 patients age <24 months, the mean depth of the ulnar artery was 2.13 mm compared to 1.65 mm for the radial artery (difference -0.48 mm 95% CI 1.08-0.12). CONCLUSIONS: The ulnar artery was larger than the radial artery in 60% of pediatric patients thus may offer an arterial cannulation site advantage due to its larger size. The use of 2-dimensional ultrasound examination allows accurate assessment of upper extremity distal arteries in order to optimize site selection for arterial cannulation in pediatric patients.

Applying Conflict Management Strategies to the Pediatric Operating Room.

Effective communication is essential in today's health care environment, and poor communication can lead to conflict among health care providers. Differences in cultures and beliefs can further incite conflict among health care team members, families, and patients. Pediatric patient care has a higher potential for conflict because decision-making responsibilities are shared among patients, parents/guardians, and clinicians. It is important to understand the phases and types of conflict because each conflict situation requires a different approach to optimize management. Equally important is an understanding of styles used by individuals to manage conflict. The Thomas-Kilmann Conflict Mode Instrument and the Dutch Test for Conflict Handling are 2 validated tools used to assess conflict management styles. The different styles include competing/forcing, collaborating/problem solving, compromising, avoiding, and yielding/accommodating. A successful physician should be able to identify the phases and types of conflict to use the conflict management approach most suitable for the given conflict.There are several techniques for managing conflict in the pediatric operating room. Acknowledging and managing one's own emotions during conflict is a pivotal first step toward diffusing the situation. Active listening is an important communication skill that improves team dynamics. Aligning the interests of the parties involved in conflict will encourage collaborative problem solving. Cultural competency training can improve communication and conflict management skills. Effective conflict management through formal education of all perioperative team members can lead to improved communication and teamwork and better patient outcomes.

Inferior Vena Cava Thrombus in a Postpartum Patient With Fontan Physiology: A Case Report.

Women with complex congenital heart disease, such as those with single-ventricle physiology, are surviving into adulthood and becoming pregnant. Because of their complex physiology, common peripartum complications pose unique risks. We describe a patient with a single ventricle who underwent an external vascular conduit, nonfenestrated Fontan procedure in childhood and then presented during the postpartum period with extensive thrombosis in her lower extremity deep venous system and inferior vena cava. In this article, we will discuss single-ventricle physiology and the implications of pregnancy, anesthetic considerations, and data for maternal and fetal outcomes in this population.

Perioperative management of a neurosurgical patient with a meningioma and recent coronary artery stent.

Patients who undergo placement of a drug-eluting coronary artery stent are prescribed dual antiplatelet therapy for one year. Early cessation of this therapy is a risk factor for a major adverse cardiac event, especially in high-risk patients. The perioperative physician team must evaluate the risk of surgical bleeding relative to the thrombotic risk during the perioperative period in patients taking dual antiplatelet therapy who must undergo intracranial neurosurgery. A 67 year old woman presented with right-sided hearing loss. Neurologic examination was significant for early papilledema and decreased hearing in the right ear. Magnetic resonance imaging showed a > 5 cm contrast-enhancing mass within her right-middle fossa with surrounding vasogenic edema and midline shift. Additional medical history was significant for diabetes, hypertension, and placement of a drug-eluting stent for coronary artery disease three months before her initial presentation. Medications included aspirin and clopidogrel. She underwent embolization of the middle meningeal arterial supply to the meningioma, then was admitted to the hospital for perioperative management of her antiplatelet therapy and telemetry monitoring. Her clopidogrel was stopped and aspirin continued perioperatively. An intravenous infusion of the antiplatelet drug, eptifibatide, replaced clopidogrel and was continued until 8 hours prior to surgical incision. During resection of the meningioma, no unusual surgical bleeding was noted. The patient was discharged on postoperative day 3 with satisfactory recovery.

Segmental wall-motion abnormalities after an arterial switch operation indicate ischemia.

We prospectively studied 29 consecutive neonates undergoing an arterial switch operation to determine if segmental wall motion abnormalities (SWMA) represented myocardial ischemia. Intraoperative transesophageal echocardiogram was recorded at baseline and twice after cardiopulmonary bypass. Cardiac troponin I (cTnI) levels were measured before sternal incision and 3, 6, 12, 24, 48, and 72 h after removal of the aortic cross-clamp. Immediate postoperative Holter and 15-lead electrocardiograms (ECG) were evaluated for ischemia. Transthoracic echocardiograms were obtained before hospital discharge. At bypass termination, immediately after protamine administration, segmental wall motion was normal in nine neonates and abnormal in 20. SWMA were transient in five and present at the time of chest closure in 15 neonates. Neonates in whom SWMA were present at chest closure had more segments involved than those in whom SWMA were transient (P > 0.001). Neonates with SWMA at chest closure had higher cTnI levels postoperatively versus neonates with normal wall motion (P = 0.02). Postoperative ECG data were available in 26 neonates. There was ECG evidence of myocardial ischemia in two of eight neonates with normal wall motion, one of five with transient SWMA, and nine of 13 with SWMA at chest closure. CTnI levels at 12, 24, and 48 h and intraoperative SWMA were predictive of postoperative SWMA. We believe these data indicate that SWMA, which persist at the completion of an arterial switch operation, and which are present in multiple myocardial segments, correlate with myocardial ischemia. Further follow-up of these patients is needed to determine if increased intraoperative myocardial ischemia correlates with long-term outcomes.

Extracellular potassium concentrations in red blood cell suspensions after irradiation and washing.

BACKGROUND: Extracellular potassium concentration [K(+)e] increases with duration of red blood cell storage. Sometimes red blood cells (RBC) are washed before transfusion to infants to reduce [K(+)e] of these components. AABB standards permit storage of washed RBCs at 4 degrees C for 24 hours. The [K(+)e] of washed RBCs during storage is not known. Experiments were performed to provide those data. STUDY DESIGN AND METHODS: One day after outdating, 26 RBC units were washed without irradiation or before or after irradiation (25 Gy), and [K(+)e] was measured for 24 hours. [K(+)e] was measured also immediately before transfusion of 29 nonoutdated irradiated and washed RBC units. RESULTS: After washing, [K(+)e] increased in a time-dependent fashion. [K(+)e] increased more rapidly in preparations of irradiated than nonirradiated RBCs. [K(+)e] was less after washing after irradiation (1.6 +/- 0.3, 2.4 +/- 0.3, 3.0 +/- 0.3, 3.6 +/- 0.3. 4.2 +/- 0.4, 5.3 +/- 0.5, 8.6 +/- 1.0, and 14.3 +/- 1.3 mEq/L at 0, 1, 2, 3, 4, 6, 12, and 24 hr; mean +/- SD) than washing before irradiation (p < 0.001). The increase in [K(+)e] during the first 6 hours after washing after irradiation was linear (0.61 +/- 0.08 mEq K(+)/L/hr). The probability of a unit of RBCs having a [K(+)e] greater than 5 mEq per L is 0.0 to 0.2 percent 3 hours after washing irradiated RBCs and 0.0 to 1.1 percent 6 hours after washing nonirradiated RBCs. CONCLUSIONS: [K(+)e] increases after washing irradiated and nonirradiated packed RBCs. After irradiation and washing, the [K(+)e] for the initial 6 hours can be predicted from the [K(+)e] immediately after washing. There is a low probability that a unit of RBCs would have a [K(+)e] greater than 5 mEq per L during 6 hours of storage at 4 degrees C after washing if the cells are not irradiated and for 3 hours if the cells are irradiated.

Effect of enalaprilat on postoperative hypertension after surgical repair of coarctation of the aorta.

OBJECTIVE: Hypertension in pediatric patients after surgical repair of coarctation of the aorta can be difficult to control and may lead to morbidity. The renin-angiotensin system mediates at least part of this hypertension. Enalaprilat, the only intravenous angiotensin-converting enzyme inhibitor, is used to treat hypertension in pediatric patients in other settings. However, its effect on postoperative hypertension during the early postoperative period in patients undergoing surgical repair of coarctation of the aorta is unknown. DESIGN: Prospective, randomized, double-blind study. SETTING: Operating room and the pediatric intensive care unit. PATIENTS: Fourteen consecutive pediatric patients between the ages of 1 and 18 yrs scheduled to undergo surgical repair of coarctation of the aorta. INTERVENTIONS: Patients were randomized to receive enalaprilat or saline placebo. Infusions were begun intraoperatively within 15 mins of aortic repair and repeated every 6 hrs. MEASUREMENTS AND MAIN RESULTS: Plasma renin activity was measured at baseline and on postoperative day 1. Blood pressure was determined at 30 mins and at 2, 4, and 6 hrs after infusion and scored relative to the preoperative blood pressure. The blood pressure in the enalaprilat group was consistently lower at 30 mins, 2 hrs, and 4 hrs after infusion (p <.05), but not at 6 hrs. Plasma renin activity was significantly lower in the placebo group on postoperative day 1. Length of stay in the pediatric intensive care unit trended shorter in the treated group. CONCLUSIONS: Conclusions are limited by a small cohort. Angiotensin-converting enzyme inhibitor therapy resulted in improved blood pressure control after coarctation repair. Further improvement of blood pressure control may be achievable by use of a larger dose of enalaprilat or a 4-hr enalaprilat-dosing interval.