Anesthesia and analgesia
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Anesthesia and analgesia · Feb 1988
Clinical TrialIonized hypocalcemia after fresh frozen plasma administration to thermally injured children: effects of infusion rate, duration, and treatment with calcium chloride.
A number of cardiac arrests and severe hypotensive episodes have been witnessed associated with the intravenous infusion of fresh frozen plasma (FFP). To clarify the possible role of hypocalcemia, 28 thermally injured anesthetized pediatric patients with massive blood loss were studied to examine the cardiovascular responses (mean arterial pressure [MAP], heart rate, ECG) to 49 infusions of FFP. Rapid, statistically significant reductions in ionized calcium ([Ca2+]) followed each of four rates (1.0, 1.5, 2.0, and 2.5 ml.kg-1.min-1 for 5 minutes) of FFP infusion (P less than 0.0001). ⋯ Adverse cardiovascular responses and reduced [Ca2+] were not significantly different between 5- and 10-minute FFP infusions. Fewer fluctuations in MAP occurred when calcium chloride (CaCl2) was administered; the least fluctuation in [Ca2+] occurred when CaCl2 was administered during the plasma infusion. It is concluded that in thermally injured children 1-17 years old: 1) Rapid infusions of FFP produce sudden but evanescent decreases in [Ca2+]; more rapid infusions result in greater reductions in [Ca2+]. 2) There is no correlation between [Ca2+] and systemic hypotension. 3) Clinically important decreases in MAP occasionally accompany the rapid infusion of FFP.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Feb 1988
Randomized Controlled Trial Comparative Study Clinical TrialLaser-induced pain for evaluation of local analgesia: a comparison of topical application (EMLA) and local injection (lidocaine).
High-energy lasers are suitable for experimental pain stimulation because they selectively activate the polymodal nociceptors. Argon laser light penetrates deep into the skin and makes this laser type preferable for simulating pain arising from surgical skin incisions. Short argon laser pulses were applied to the skin and three parameters were quantified before and during analgesia; sensory threshold, pain threshold, and the pain-related cortical response (latency and amplitude). ⋯ During the next 30 minutes after removal of the cream, the thresholds increased further. The increase in analgetic effect after removal of the cream was studied using different times (15, 30, 60, 80, 100, and 120 minutes) for topical EMLA cream application. Total sensory block was reached 20 minutes after removal of application for 80 minutes or immediately after removal of the cream after it was applied for 100 or 120 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Feb 1988
ReviewThe effect of incremental positive end-expiratory pressure on right ventricular hemodynamics and ejection fraction.
The effects of incremental positive end-expiratory pressure (PEEP) on right ventricular (RV) function were evaluated in 36 (n = 36) ventilated patients. Positive end-expiratory pressure was increased from 0 (baseline) to 20 cm H2O in 5-cm H2O increments and RV hemodynamics and thermally derived right ventricular ejection fraction (RVEF), right ventricular end-diastolic volume index (RVEDVI), and right ventricular end-systolic volume index (RVESVI) were computed. Right ventricular contractility was determined from the analysis of RV systolic pressure-volume relations. ⋯ The slope (E) of the relation of RV peak systolic pressure to RV end-systolic volume index decreased from 0.26 mm Hg.m2.ml-1 between PEEP of 0-15 cm H2O to 0.05 mm Hg.m2.m-1 at PEEP greater than 15 cm H2O. It is concluded that low levels of PEEP have a predominant preload reducing effect on the RV. Above 15 cm H2O PEEP, RV volumes increase and E decreases, consistent with increased RV afterload and a decline in RV contractility.
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Anesthesia and analgesia · Feb 1988
Inadvertent subdural injection: a complication of an epidural block.
Twenty-one hundred eighty two consecutive lumbar epidural injections were studied to determine the incidence of inadvertent subdural block retrospectively. A subdural block is defined as an extensive neural block in the absence of subarachnoid puncture, that is out of proportion to the amount of local anesthetic injected. ⋯ This study, however, reports an incidence of 0.82% from a sample size of 2182 patients. Cadaveric dissection was also performed, further clarifying the presence and anatomic position of the subdural space.