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D L Bourke

Publications and source records attributed to D L Bourke.

17 recordsLinked to original sources
PubMed1989

The steady-state and rebreathing methods compared during morphine administration in humans.

1. We examined the quantitative and qualitative differences between the steady-state and rebreathing methods of determining CO2-response curves before and after each of two doses of intravenous morphine (0.07 and 0.14 mg kg-1) in four healthy male humans. 2. During each study session steady-state and rebreathing CO2-response curves were determined as an ordered pair (separated by 15 min). Carbon dioxide-response curves were determined for control, after 0.07 mg kg-1 morphine, and after a total of 0.21 mg kg-1 morphine. Each subject was studied on a second occasion when the order of the CO2-response pairing was reversed. 3. The results are discussed and related to a model that may account for the differences based on the step increase in CO2 at the onset of rebreathing, the rate of rise of CO2 during rebreathing and the time constant for the central chemoreflex. 4. Our empirical conclusion is that morphine causes a parallel right shift of the steady-state CO2-response curve and causes a non-specific decrease in the slope of the rebreathing CO2-response curve. We suggest that the parallel shift of the steady-state CO2-response curve is specific to drugs acting on opioid receptors.

Adult↗
PubMed1978

Cardiac arrest.

Explore the source record for details and available documents.

Atropine↗
PubMedDate not supplied

Epidural opioids during laminectomy surgery for postoperative pain.

STUDY OBJECTIVE: To determine whether morphine applied directly to the dura during laminectomy surgery provides superior postoperative analgesia during the first 24 hours. DESIGN: Randomized, double-blind study. SETTING: A university-affiliated hospital. PATIENTS: Twenty ASA physical status I and II patients ages 18 to 60 years. INTERVENTIONS: Simultaneous topical dural application and intramuscular (IM) injection of unknown solutions of saline and morphine 3 mg. MEASUREMENTS AND MAIN RESULTS: Postoperative analgesia was assessed using the visual analog scale (VAS), a modified McGill-Melzack pain questionnaire, subjective nursing evaluations, and the amount of supplemental analgesic medication used. Patients were observed for complications and side effects. Compared with the patients who received epidural saline and IM morphine, the patients who received epidural morphine and IM saline had less postoperative pain as determined by VAS scores, nursing evaluations, and amount of supplemental opioid analgesic doses (1.6 +/- 1.2 vs. 4.1 +/- 1.2 analgesic doses per patient; p less than 0.05) required in the first 24 hours. Minor side effects were similar for the two groups. No patient developed respiratory depression. CONCLUSIONS: Morphine 3 mg applied topically to the dura at the end of laminectomy surgery is a simple, safe, and effective way of providing improved postoperative analgesia.

Adolescent↗
PubMedDate not supplied

A randomized trial of perioperative hemodilution versus transfusion of preoperatively deposited autologous blood in elective surgery.

Hemodilution, one of several methods proposed to decrease homologous blood transfusion in elective surgery, has not been studied in a prospective controlled trial to determine if it is successful. A prospective, randomized controlled study was conducted to determine if hemodilution can serve as an alternative to preoperative autologous blood donation. Fifty patients were randomized to preoperatively deposit 3 units of autologous blood or to undergo hemodilution immediately before elective radical retropubic prostatectomy. All patients were treated under a standard protocol, including surgery performed by a single surgeon. The preoperative deposit groups received a mean of 2.44 +/- 1.0 units of blood; 2 of 25 patients required homologous blood transfusion for blood loss of 2600 mL and 1700 mL. The hemodilution group received a mean of 2.88 +/- 0.4 units of autologous blood: no hemodilution patient received homologous blood. At discharge, the mean hematocrit for the preoperative deposit group was 35.5 +/- 4.9 (0.35 +/- 0.05), and that for the hemodilution group was 31.8 +/- 4.7 (0.32 +/- 0.05) (p less than 0.001). There were no differences in perioperative morbidity in the treatment groups. The best predictor of discharge hematocrit was the initial hematocrit of the patient. It can be concluded that hemodilution can safely replace or at least augment preoperative autologous donations as a means of decreasing homologous blood transfusion in study patients. These results can be applied to any elective surgery procedure in which a 1000-mL blood loss is anticipated. Other advantages of hemodilution, including convenience, lower cost, and better preservation of all components of autologous blood, suggest that this practice deserves wider application.

Blood Transfusion, Autologous↗