Evidence that blood pressure remains under the control of arterial baroreceptors in renal hypertensive rats.

The purpose of the present study was to determine the range of the influence of the baroreflex on blood pressure in chronic renal hypertensive rats. Supramaximal electrical stimulation of the aortic depressor nerve and section of the baroreceptor nerves (sinoaortic denervation) were used to obtain a global analysis of the baroreceptor-sympathetic reflex in normotensive control and in chronic (2 months) 1-kidney, 1-clip hypertensive rats. The fall in blood pressure produced by electrical baroreceptor stimulation was greater in renal hypertensive rats than in normotensive controls (right nerve: -47 +/- 8 vs -23 +/- 4 mmHg; left nerve: -51 +/- 7 vs -30 +/- 4 mmHg; and both right and left nerves: -50 +/- 8 vs -30 +/- 4 mmHg; P < 0.05). Furthermore, the increase in blood pressure level produced by baroreceptor denervation in chronic renal hypertensive rats was similar to that observed in control animals 2-5 h (control: 163 +/- 5 vs 121 +/- 1 mmHg; 1K-1C: 203 +/- 7 vs 170 +/- 5 mmHg; P < 0.05) and 24 h (control: 149 +/- 3 vs 121 +/- 1 mmHg; 1K-1C: 198 +/- 8 vs 170 +/- 5 mmHg; P < 0.05) after sinoaortic denervation. Taken together, these data indicate that the central and peripheral components of the baroreflex are acting efficiently at higher arterial pressure in renal hypertensive rats when the aortic nerve is maximally stimulated or the activity is abolished.

Influence of anesthetics on pharyngeal flap surgery: a 23-year study.

This study assessed the influence of anesthetics on early complications after pharyngeal flap surgery. A 23-year retrospective chart review was carried out of all patients at the authors' institution who underwent superiorly based pharyngeal flap surgery. Variables analyzed were gender, age at the time of surgery, cleft type, anesthesia procedure used and complications in the early postoperative period. 2299 patients (50% male; 50% female) who underwent pharyngeal flap surgery between 1980 and 2003 were reviewed. The highest number of surgeries was performed in patients aged 11-20 years. There were 1042 patients with at least one type of complication. Of these, 39 required reoperation to control complications such as bleeding and airway obstruction. There were no records of death. Vomiting and pain were the most frequent postoperative complications (16% and 14% of patients, respectively). Lower complication rates were observed when anesthesia protocols included sevoflurane, propofol and opioids.

Analgesic and anti-inflammatory dose-response relationship of 7.5 and 15 mg meloxicam after lower third molar removal: a double-blind, randomized, crossover study.

Fifty patients were scheduled to undergo removal of symmetrically positioned lower third molars in two separate appointments. Meloxicam 7.5 or 15 mg was once daily administered in a double-blind, randomized and crossover manner after the surgery for 4 days. Objective and subjective parameters were recorded for comparison of postoperative courses. Patients treated with 7.5mg meloxicam who underwent osteotomy reported higher pain scores at 1.5, 3, 4, 10, 12 and 16 h (P<0.05) and ingested a greater amount of rescue analgesic medication (P<0.05) than those who did not require osteotomy. A higher percentage of patients who underwent osteotomy medicated with 7.5mg meloxicam needed rescue medication as compared to those who did not require osteotomy (P<0.05). There was a similar mouth opening at suture removal compared with preoperative values for both doses (P>0.05). There were no significant differences concerning swelling observed on the 2nd or 7th postoperative days in comparison with baseline (P>0.05) between the two doses. Pain, trismus and swelling after lower third molar removal not requiring osteotomy can be successfully controlled by a dose regimen of 7.5mg meloxicam once daily. For more aggressive extractions 15 mg meloxicam is advisable.

Long-term analysis of the hypertension produced by sinoaortic denervation in the rat.

The increases in pressure lability and in mean arterial pressure (MAP) produced by sinoaortic denervation (SAD) in the rat were studied during a 16 h period of continuous pressure measurement 1, 7, 15, 30, 90 and 180 days after surgery. All groups of SAD rats showed increased pressure lability that was estimated from the standard deviation of approximately 960 pressure values taken one per min from the continuous record. The average standard deviation increased 40-90% and the distribution curves of pressure during the 16 h period was wider in the group of SAD rats than in the controls. Although the increased lability of SAD rats remained unchanged, the average minute-to-minute increase in MAP declined during the postoperative period studied. MAP dropped from 151 +/- 5 mmHg (vs 114 +/- 1 mmHg for the control) on the 1st day to 141 +/- 3, 135 +/- 3, 133 +/- 2, 132 +/- 2 and 130 +/- 2 mmHg on days 7, 15, 30, 90 and 180 after SAD, respectively. Movement-related pressure dips were observed in the SAD rats monitored for 16 h in contrast to the other natural states of behavior (walking, eating, grooming) that usually produced an increase in the MAP of control rats and tended to produce exaggerated pressor responses in SAD rats. SAD rats showed increased pressure lability and an elevation of MAP from 130-135 mmHg to 150 mmHg for up to 10 min in response to an acoustic stimulus. The data demonstrate the importance of using quiet and undisturbed conditions to assess the true pressure increase produced in rats by sinoaortic denervation.(ABSTRACT TRUNCATED AT 250 WORDS)