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Objective: This study was designed to evaluate whether a continuous low-dose lidocaine infusion reduces postoperative pain and anxiety in patients undergoing coronary artery bypass grafting (CABG) and to retrospectively examine time to extubation, intensive care unit stay (ICU), and hospital length of stay., Design: A double-blinded, randomized, and prospective approach., Setting: Hospital patients undergoing first-time CABG., Participants: After informed consent, 100 patients were enrolled in this study., Interventions: Lidocaine infusion or placebo substitute was begun after induction of anesthesia. The fentanyl/midazolam infusion was discontinued on ICU admission; lidocaine or placebo continued until ICU discharge. Supplemental fentanyl, midazolam, or propranolol was administered for pain, anxiety, or hemodynamic stress., Measurements and Main Results: Drug dosages were compared between groups. Postoperative assessment included visual analog pain score, hemodynamics, sedation score, and nursing assessment. Mean total dosages of fentanyl, midazolam, and propranolol between the lidocaine and placebo groups were 620.40 +/- 815.74 microgram versus 689.16 +/- 692.99 microgram, p = 0.244; 0.54 +/- 1.13 mg versus 1.20 +/- 2.44 mg p = 0.465; 0.11 +/- 0.75 mg versus 3.56 +/- 17.2 mg, p = 0.564, respectively. Times to extubation, ICU length of stay, and hospital stay did not achieve statistical significance., Conclusions: Continuous infusion of low-dose lidocaine did not significantly decrease supplemental fentanyl, midazolam, or propranolol requirement postoperatively. Similarly, a lidocaine infusion does not result in reduced time to extubation. ICU stay, or hospital length of stay.

When systemic cooling and rewarming are performed during cardiopulmonary bypass (CPB), the pulmonary artery temperature typically decreases after CPB. This decrease may be rapid enough to cause substantial underestimation of cardiac output (CO) measured by thermodilution, due to changing baseline temperature during the thermodilution measurement. In 16 patients undergoing CPB for coronary artery grafts, digital recording of pulmonary artery temperature was done during room-temperature thermodilution CO (TDCO) injections. TDCO were computed with and without correction for baseline temperature decrease. Prior to CPB, the temperature change was -0.013 degrees C/min, producing no significant effect on CO measurements; the coefficient of variation of CO measurements was 5.1%. One minute after CPB the temperature change was -0.144 degrees C/min, producing a CO measurement error of -0.57 +/- 0.52 l/min (SD), or about 11% of the average CO; the range of the error was 0.05 to -2.0 l/min. Ten minutes after CPB the temperature change was -0.063 degrees C/min, and CO error was -0.31 +/- 0.36 (0.15 to -1.20) l/min. At 30 min the temperature change was -0.012 degrees C/min (not significant), and CO error was -0.13 +/- 0.14 l/min. Duration of CPB was 104 +/- 30 min, with rewarming for 44 +/- 13 min; the average minimum bladder temperature was 25.1 +/- 2.3 degrees C during cooling and 36.7 +/- 0.7 degrees C at the end of CPB. Under these conditions TDCO measurements within the first 10 min after CPB often underestimate the true CO.

The pressure in either the radial (n = 88) or proximal brachial artery (n = 82) was compared with aortic pressure before and after cardiopulmonary bypass (CPB) in patients receiving coronary artery bypass grafts. Radial artery pressures were measured via 20-G 5-cm long catheters, brachial artery pressures via 20-G 12.7-cm catheters, and aortic pressures were measured via a luer port in the aortic perfusion cannula. Transducers were connected via 122-cm long tubing. For the various systems, mean natural frequencies were 16.1 to 17.7 Hz and damping coefficients were 0.16 to 0.27. Before CPB the brachial systolic, diastolic, and mean pressures were 108.2 +/- 5.2%, 100.9 +/- 2.8%, and 99.6 +/- 2.3% of aortic; respective radial pressures were 113.9 +/- 9.6%, 99.5 +/- 2.8%, and 98.4 +/- 2.8% of aortic. Immediately after CPB the brachial pressures were 99.5 +/- 7.5%, 98.9 +/- 3.5%, and 97.4 +/- 2.9% of aortic, whereas respective radial pressures were 92.1 +/- 14.6%, 94.7 +/- 5.6%, and 90.8 +/- 7.4%. All brachial and radial as a per cent of aortic pressure medians were significantly different, and except for prebypass diastolic and mean, the variance for brachial pressures was significantly less than that for pressures in the radial artery. The prebypass brachial correlation (r) with aortic for systolic, diastolic, and mean were 0.90, 0.98, and 0.98; respective radial correlations with aortic were 0.78, 0.97, and 0.95. Postbypass brachial systolic, diastolic, and mean correlations were 0.91, 0.97, and 0.98; radial were 0.50, 0.93, and 0.83. Brachial artery pressures were more accurate and reliable than radial artery pressures.

To determine the cause of decreased cardiac output (CO) resulting from the use of PEEP, hemodynamic and pulmonary parameters and radiographic estimates of left ventricular volumes were observed in nine dogs under three conditions: control, PEEP (15 cm H2O), and PEEP with intravascular (IV) volume expansion. Volume expansion was sufficient to return the CO to control values. Cardiac index (CI), stroke volume index (SI), left ventricular stroke work index (LVSWI) all decreased approximately 30 per cent with the application of PEEP. Ejection fraction remained unchanged. With IV volume expansion, the CI, SI, left ventricular end-diastolic volume index, and LVSWI returned to approximate control values. The transmural left ventricular end-diastolic pressure (TMLVEDP) did not change significantly. The authors therefore conclude that reduced left ventricular preload is the cause of decreased cardiac output by PEEP and that indirect evidence of preload (transmural left ventricular end-diastolic pressure) is not an adequate assessment of the force-length relationship under the conditions stated.

Electrocardiogram lead CB5 was compared with lead V5 kin 27 patients undergoing coronary artery bypass graft surgery. Lead CB5 is a bipolar lead consisting of a negative electrode over the center of the right scapula and the positive electrode over the fifth interspace in the anterior axillary line. Comparison of CB5 and V5 tracings made while the chest was closed showed the ventricular deflections to be 20% larger in the CB5 lead. The ventricular deflections were highly correlated (r = 0.95 to 0.98). The average P wave voltage was 90% greater in the CB5 lead, and the relative increase in P wave voltage was greater (p less than 0.01) than the 20% increase in the RS deflection. Tracings made while the chest was open gave similar results. The CB5 lead is simple to apply and provides tracings equivalent to the V5 when monitoring for ischemia while allowing easier recognition of P waves.

Pituitary apoplexy occurred in 3 patients in the immediate postoperative period following cardiac operation with cardiopulmonary bypass. In this setting, this complication is extremely rare and not widely recognized. Precipitating factors may be related to the extracorporeal bypass apparatus, anticoagulation, low cerebral blood flow, and even anesthetic agents. Neurosurgical decompression can be safely performed in the early postoperative period following open-heart operations.

We compared the effects of 15 and 60 micrograms/kg fentanyl used for induction in 40 patients, 50-72 yr old, with coronary artery disease and mildly impaired ventricular contractility. Morphine (0.1 mg/kg) and scopolamine (0.4 mg) were used for premedication. Crystalloid (500 ml) was administered before induction, and nitroglycerin (0.3 micrograms X kg-1 X min-1) was infused during the study. Fentanyl, 15 or 60 micrograms/kg, was administered at a rate of 1.2 micrograms X kg-1 X sec-1. Pancuronium (0.04 mg/kg) and metocurine (0.16 mg/kg) were used for muscle relaxation. Data were collected 2 min before induction (baseline), before intubation (3 min), at 6 min, and at 13 min. Responses to 15 and 60 micrograms/kg were similar. At 3 min the heart rate (HR) in patients given 15 micrograms/kg increased by 6; whereas the HR in those given 60 micrograms/kg increased by 14 (P less than 0.01). Subsequent differences in HR were not significant. There were no dose-related differences in mean arterial pressure, cardiac index, central venous pressure, or pulmonary capillary wedge pressure. The EEG showed high-voltage low-frequency activity within 2 min in all patients. Arterial plasma fentanyl concentrations at 3 min averaged 25.9 +/- 3.8 ng/ml with 15 micrograms/kg and 89.9 +/- 15.2 ng/ml with 60 micrograms/kg. At 4 hr, plasma concentrations averaged 0.4 +/- 0.2 ng/ml and 3.6 +/- 0.7 ng/ml, respectively. We conclude that anesthesia for induction and intubation is achieved by the rapid administration of 15 micrograms/kg fentanyl and that 60 micrograms/kg has no substantially different effect on cardiovascular responses.

Twenty cases of renal carcinoma with tumor thrombus extending into the vena cava or atrium, in which cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) were used, are reviewed. Arterial, central venous (n = 9), or pulmonary artery catheters (n = 11), ECG, and rectal or bladder and pharyngeal temperatures were used for monitoring. The anesthetic was a high-dose narcotic supplemented with a nondepolarizing relaxant and a volatile agent. The surgery consisted of mobilization of the kidney followed by CPB via atrial and aortic cannulae, cooling via CPB, exsanguination, and removal of thrombus during DHCA. Duration of cooling was 21 +/- 7 minutes to a pharyngeal temperature of 15.8 degrees +/- 2.6 degrees C with alpha-stat pH management; DHCA lasted 26 +/- 10 minutes, and rewarming was continued to a mean pelvic temperature of 36.2 degrees C. Duration of surgery was 8.1 +/- 1.6 hours. The mean initial hematocrit was 33.5%, mean lowest Hct during CPB was 16.9%, and mean Hct at the end of surgery was 30%. Intraoperatively, 9.0 +/- 6.4 units of blood were used, and most patients received component therapy. Average crystalloid use was 7 L, and albumin or hetastarch (1.3 +/- 0.9 L) was used in 13 patients. One patient with severe cardiac disease could not be weaned from CPB. In the 19 operative survivors, there were no neurological deficits. There was one late death from pulmonary complications. The use of thiopental (n = 13), dexamethasone (n = 11), or mannitol (n = 19) was not clearly related to outcome. Hypothermia, hemodilution, alpha-stat pH management, and normoglycemia are believed to be important aspects of perioperative care.(ABSTRACT TRUNCATED AT 250 WORDS)