Successful weaning from cardiopulmonary bypass with central venous prostaglandin E1 and left atrial norepinephrine infusion in patients with acute pulmonary hypertension.

OBJECTIVE: Postoperative pulmonary hypertension increases the mortality risk in cardiac surgery. We have used central venous prostaglandin E1 (PGE1) and left atrial norepinephrine (NE) infusion to wean from cardiopulmonary bypass (CPB) patients with refractory postoperative pulmonary hypertension. DESIGN: Observational, nonrandomized study. SETTING: Department of Cardiac Surgery in a university hospital. PATIENTS: We studied 10 nonconsecutive American Society of Anesthesiologists III and New York Heart Association class III-IV patients with postoperative pulmonary hypertension and low cardiac output syndrome preventing separation from CPB. INTERVENTIONS: Patients received right atrial PGE1 (31.5 +/- 6.26 ng/kg/min) and left atrial NE (0.11 +/- 0.02 microg/kg/min) infusion. Hemodynamic data were obtained before CPB (T0), after CPB under maximal inotropes and vasodilator infusion (T1), 10 mins (T2) and 12 hrs (T3) after PGE1 and NE infusion, and 48 hrs after withdrawal of PGE1 and NE (T4). MEASUREMENTS AND MAIN RESULTS: All patients were successfully weaned from CPB and survived. The biatrial infusion of PGE1 and NE caused a dramatic reduction in mean pulmonary artery pressure (from 42.8 +/- 5.1 mm Hg at T1 to 28.5 +/- 2.6 mm Hg at T2 and 20.5 +/- 2.0 mm Hg at T4), pulmonary vascular resistance index (from 1158 +/- 269 dyne x sec/cm5 x m2 at T1 to 501 +/- 99 dyne x sec/cm5 x m2 at T2 and 246 +/- 50 dyne x sec/cm5 x m2 at T4), and pulmonary-to-systemic vascular resistance index ratio (from 0.61 +/- 0.17 at T1 to 0.20 +/- 0.04 at T2 and 0.11 +/- 0.03 at T4). Cardiac index increased from 1.7 +/- 0.2 L/min/m2 at T1 to 2.3 +/- 0.2 L/min/m2 at T2 and 2.9 +/- 0.1 L/min/m2 at T4. CONCLUSIONS: In patients with refractory postoperative pulmonary hypertension, the combined administration of low-dose PGE1 in the right atrium and NE in the left atrium is an effective means to wean patients from cardiopulmonary bypass.

Calcium chloride minimizes the hemodynamic effects of propofol in patients undergoing coronary artery bypass grafting.

OBJECTIVE: To assess the hemodynamic effects of propofol and the counteracting effect of calcium chloride (CaCl2) in patients undergoing coronary artery bypass grafting (CABG). DESIGN: Prospective, randomized study. SETTING: University hospital, department of cardiac surgery. PARTICIPANTS: Fifty-eight patients undergoing elective CABG, divided into group A (n = 29) and group B (n = 29). INTERVENTIONS: Anesthesia was induced with a combination of fentanyl, 7 microg/kg; pancuronium, 0.1 mg/kg; and propofol, 1.5 mg/kg, administered over 60 seconds. A blinded investigator administered saline in group A patients and 10 mg/kg of CaCl2 in group B patients at the same speed and same time as propofol administration through another lumen of the central venous catheter. MEASUREMENTS AND MAIN RESULTS: Hemodynamic data were obtained at baseline (T0), 2 minutes after anesthesia induction (T1), and 2 minutes after tracheal intubation (T2). Heart rate decreased significantly in group A patients (86.2+/-11.3 beats/min at T0 and 72.8+/-7.5 beats/min at T2; p < 0.001). Mean arterial pressure decreased significantly in patients in both groups (group A, 108.0+/-12.0 mmHg at T0; 74.6+/-14.6mmHg at T2;p < 0.001 and group B, 106.0+/-10.2 mmHg at T0; 90.4+/-10.0 mmHg at T2; p < 0.05). Stroke volume index, cardiac index, and cardiac output decreased in group A patients (39.4+/-4.1 mL/beat/m2 at T0 and 28.8+/-5.2 mL/beat/m2 at T2; p < 0.05; 3.4+/-0.6 L/min/m2 at T0 and 1.9+/-0.3 L/min/m2 at T2; p < 0.001; 5.9+/-0.9 L/min at T0 and 3.4+/-0.4 L/min at T2; p < 0.001, respectively), whereas in group B patients, changes were negligible (38.1+/-7.0 mL/beat/m2 at T0 v 35.7+/-6.6 mL/beat/m2 at T2; (NS) 3.3+/-0.5 L/min/m2 at T0 v 2.7+/-0.3 L/min/m2 at T2; (NS) 5.7+/-0.9 L/min at T0 v 4.7+/-0.5 L/min at T2; (NS), respectively). CONCLUSION: Simultaneous administration of CaCl2 during the induction of anesthesia minimizes the potential negative effect of propofol on cardiac function in cardiac patients.

Do we know the costs of what we prescribe? A study on awareness of the cost of drugs and devices among ICU staff.

OBJECTIVE: To evaluate the level of cost awareness of drugs and devices among intensive care unit (ICU) doctors with variable levels of experience (senior intensivists, junior intensivists, residents). DESIGN: Interview-questionnaire. SETTING: ICU of the University of Rome "La Sapienza". PARTICIPANTS: 60 ICU doctors (40 specialists in anaesthesia and intensive care, 20 residents). MEASUREMENTS AND RESULTS: The estimated prices of drugs and devices were compared with the correct prices; responses within a range +/- 20% of the true price were arbitrarily considered correct; all the subgroups of doctors made inaccurate estimates of the prices, showing an absence of any impact of professional experience of cost awareness. CONCLUSION: The doctors in the study showed a high level of inaccurate cost awareness of drugs and devices.

Treatment of acute respiratory failure by prolonged non-invasive ventilation in a child.

PURPOSE: To evaluate the feasibility and the efficacy of non-invasive ventilation (NIV) by nasal mask in a paediatric patient. CLINICAL FEATURES: A four-year-old girl with acute lymphocytic leukaemia (ALL L1, pre-pre B) complicated by acute respiratory failure was treated with NIV. ON admission she exhibited hyperpyrexia (40C), pancytopaenia and severe hypoxia with hypocapnia (PaO2 = 45 mmHg; PaCO2 = 28.2 mmHG; pH = 7.30; SpO2 = 76%; ABE = -7.3 mmol.L-1. With NIV, PaO2 improved (PaO2 = 78 +/- 8 mmHG; SpO2 = 86 +/- 2; PaCO2 = 39 +/- 2) throughout the first day. Treatment was continued for six days until the patient was discharged. No complications were recorded. CONCLUSION: Non-invasive ventilation by nasal mask may represent a choice in the treatment of acute respiratory failure of parenchymal origin in paediatric haematological patients.

Effects of three techniques of lung management on pulmonary function during cardiopulmonary bypass.

In this study, 30 patients undergoing elective myocardial revascularization were divided randomly in three groups (10 patients each) with different management of the lungs during CPB: Group 1, lungs deflated; Group 2, static inflation with PEEP = 5 cmH2O and FIO2 = 1.0; Group 3, static inflation with PEEP = 5 cmH2O and FIO2 = 0.21. Measurements (Qs/Qt, P(A-a)O2, PaO2, Cstat, Cdyn, PIP, AUTO-PEEP, Rrs,max, Rrs,min and DRrs) were performed after the induction of anesthesia (T0), 20 minutes (T1) and 2 hours (T2) after the end of CPB. Respiratory mechanics data were obtained only at T0 and T2 because the sternal retraction. The Group 1 presented a statistically significant increase in Qs/Qt, P(A-a)O2 and Peak Inspiratory Pressure (PIP); in this group we noticed also a decrease in PaO2 values, static compliance (Cstat) and dynamic compliance (Cdyn) values comparing basal versus T1 and T2 values. The Group 2 showed a statistically significant increase in Qs/Qt and P(A-a)O2 values; also in this group we observed a statistically significant decrease in PaO2 and Cdyn values comparing basal versus T1 and T2 values. The Group 3 presented a statistically significant decrease in PaO2 values (basal versus T1 and T2); this group also presented an increase in Qs/Qt values, in the immediate postbypass period (T1), and P(A-a)O2 values significantly increase comparing basal versus T1 and T2 values. In all the three groups the respiratory system resistance and AUTO-PEEP values were unchanged after the end of CPB. The comparison between the groups showed a significant minor impairment of gas exchange (PaO2 and P(A-a)O2), Qs/Qt and Cstat in the third group of patients. These results show that lungs inflation with air during CPB, effectively preserve respiratory system mechanics: this might be due to a preservation of bronchial perfusion simply due to the mechanic expansion of the lung otherwise compromized when the lungs are completely collapsed. However it is necessary to emphasize that CPB has negative effects on gas-exchange whatever technique of lung management is used.

Central venous catheterization in pediatric patients affected by hematological malignancies.

The objective of this retrospective study was to evaluate the significance and complications of percutaneous central venous catheterization in pediatric patients affected by hematologic malignancies. One hundred and fifty-eight central venous catheters were inserted in 125 pediatric patients (male/female 67/58; median age: 4 years; range 10 m - 6 y.) affected by hematological malignancies. Venous access was obtained by means of a tunnelled silicone rubber Groshong catheter inserted percutaneously in the subclavian vein (91.1%), the internal jugular vein or in the femoral vein. The medial duration of catheterization was 231.8 days (range 8-1014 days). The total number of catheter days was 33,792 (92.6 years). There were no complications related to catheter insertion. Only one patient developed significant post-operative bleeding. One hundred and nine catheters (68.9%) were removed when they were no longer needed and 49 (31.1%) were removed due to complications: 6 catheter occlusions (12.2%), 7 were accidentally withdrawn (14.3%), 3 for local infections (6.1%) and 33 for catheter-related infection (67.3%). A Groshong catheter seems to provide good access to the blood stream for a long period of time with a low incidence of complications in children with acute hematological malignancies.

Chronobiology of blood pressure in childhood: implications for tracking.

Chronobiology, in its methodological evolution, developed data series analyses paying particular attention to blood pressure (BP), because of the importance of this biorhythmic variable for assessing the risk of developing hypertension. An example of the potentiality of the chronobiologic procedures is given in the present report which deals with the inferential analysis of the BP 24-h patterns in 3-12 year-old children. By using the chronobiologic methodology, time-qualified standards for BP are calculated. Rhythmometric parameters for circadian rhythm of systolic and diastolic components of BP are also computed. Data presented are a tangible outcome for emphasizing the introduction of chronobiology in epidemiology and pediatrics in order to optimize the primary prevention and care of hypertension taking as reference the chronobiologic standards of BP.