Regional analgesia in the intensive care unit. Principles and practice.

Nociception is a complicated process, and only in recent years have the neural pathways and mediators of pain transmission been unraveled. Several regional anesthetic interventions, most notably epidural drug delivery, can interrupt nociception and provide safe and effective pain control in critically ill patients while substantially reducing the need for systemic medications. This article discusses the possibilities for regional control of the neurobiology of nociception and describes the arsenal of regional anesthetic techniques available to the intensivist. Used wisely, regional techniques can provide excellent pain control and may have a significant role in improving overall patient outcome. Regional analgesia offers the best opportunity to provide substantial analgesia without significant central opioid effects. Well-conducted regional analgesia can reduce many of the unpleasant or potentially problematic side effects observed when traditional intravenous medications are used exclusively for pain control.

Effect of propofol with and without EDTA on haemodynamics and calcium and magnesium homeostasis during and after cardiac surgery.

OBJECTIVE: To determine the effect of the addition of disodium edetate (EDTA) to propofol on haemodynamics, ionised calcium and magnesium serum concentrations, and adverse events during cardiac surgery. DESIGN: Double-blind, randomised, multicenter trial. SETTING: Operating room and intensive care unit of 5 academic health centres. PATIENTS: A total of 102 evaluable patients, aged 34 to 85 years, undergoing first-time, elective coronary artery bypass graft surgery. INTERVENTIONS: Comparison of propofol with EDTA and propofol without EDTA, each in conjunction with the opioid sufentanil, for intraoperative anaesthesia and postoperative sedation. MEASUREMENTS AND RESULTS: There were no significant differences at any time between the two formulations in any clinical chemistry measurements, including ionised calcium, ionised magnesium, total calcium, parathyroid hormone, blood urea nitrogen, creatinine, sodium, potassium, and phosphate. During bypass, the mean concentration of ionised calcium decreased to below the normal range, but the decrease was similar in both groups (propofol with EDTA, 0.98 +/- 0.07 mmol/L [N = 51]; propofol, 0.99 +/- 0.10 mmol/ L [N = 51]; p = NS). Calcium concentration returned to normal after rewarming. Mean ionised magnesium concentrations remained within normal limits in both groups. Similarly, there were no clinically meaningful differences between treatments with respect to haemodynamic variables, efficacy variables, or incidence of adverse events. CONCLUSIONS: The inclusion of EDTA in the current formulation of propofol appears to have no significant effects on calcium and magnesium profiles, renal function, haemodynamic variables, or other indicators of safety and efficacy during intraoperative anaesthesia and postoperative sedation in patients undergoing cardiac surgery.

A multicenter evaluation of a new continuous cardiac output pulmonary artery catheter system.

OBJECTIVE: To validate a new system of continuous cardiac output monitoring. DESIGN: Multicenter, prospective, nonrandomized clinical study. SETTING: Four university hospitals. PATIENTS: Forty-seven adult intensive care unit patients. INTERVENTIONS: Pulmonary artery catheterization. MEASUREMENTS AND MAIN RESULTS: Continuous and bolus cardiac output measurements were obtained over 72 hrs. The 327 continuous cardiac output measurements compared favorably with bolus cardiac output measurements (bias = 0.12 L/min, precision = +/-0.84). The continuous cardiac measurement was not adversely affected by temperatures of <37 degrees C or >38 degrees C, high (>7.5 L/min) or low (<4.5 L/min) cardiac output values, or duration (72 hrs) of the study. CONCLUSIONS: This continuous cardiac output system provides a reliable estimate of cardiac output for clinical use if applied in conditions similar to this study. The combination of a continuous measure of cardiac output with other continuous physiologic monitoring (arterial and mixed venous oxygen saturation, oxygen consumption, etc.) may provide important information that no single parameter could achieve.

Arterial blood gas monitoring.

Arterial blood gas determinations (ABGs) play an important role in diagnosing derangements in acid-base balance, oxygenation, and ventilation. Frequent assessment is necessary in the management of critically ill patients. This article reviews the technologic evolution of modern blood gas analysis and the clinical application of monitoring hydrogen ion content (pH), blood oxygen tension (PO2), and carbon dioxide tension (PCO2).

Phantom orchalgia.

Chronic scrotal pain is most commonly explained by the radiculitis that is caused by low back strain. The diagnosis is made chiefly by taking a careful history and by excluding other causes. Treatment directed to relieve sensory nerve root irritation at the T10 to L1 levels is often successful.