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Biomedical subjects

G Wallin

Publications and source records attributed to G Wallin.

At least 91 records · Page 5Linked to original sources
PubMed1988

Inhibition of peritonitis by amide local anesthetics.

Peritonitis was induced in rats by exposing the peritoneal surface to 0.1 M hydrochloric acid (HCl). Peritonitis was quantified by extraction of Evans blue-bound albumin from the tissue exposed to HCl and analyzed by a spectrophotometric technique. In the first set of experiments, one group of rats had the peritoneal surface exposed to HCl following local pretreatment with isotonic saline; a second group of rats had the peritoneum exposed to HCl after topical pretreatment with an equal volume of lidocaine 1%, whereas in a third group the peritoneal surface was exposed only to saline without HCl. The experimental design in the second set of experiments was similar to that of the first set except that bupivacaine 0.5% was used instead of lidocaine in the second group. Results show a significant inhibition of peritonitis in the groups pretreated with lidocaine (P less than 0.01) and bupivacaine (P less than 0.05) compared with rats in the saline pretreated group. In the lidocaine-pretreated group Evans blue-albumin extravasation did not differ significantly from the rats not receiving HCl, whereas the bupivacaine-pretreated group showed a slightly but significantly (P less than 0.05) more pronounced peritonitis than control rats not exposed to HCl. In the third set of experiments the peritoneum was topically treated with either lidocaine 1%, bupivacaine 0.5%, or isotonic saline after first having exposed the peritoneal surface to HCl. A significant inhibition of albumin extravasation was seen following lidocaine (P less than 0.001) or bupivacaine (P less than 0.001) treatment compared with treatment with isotonic saline.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Is high and fluctuating muscle nerve sympathetic activity in the sleep apnoea syndrome of pathogenetic importance for the development of hypertension?

Muscle nerve sympathetic activity was recorded in six patients with the sleep apnoea syndrome (SAS). Compared with age- and sex-matched control patients, an increased activity during wakefulness was found. Sleep apnoic events were associated with sequencies of progressively increasing sympathetic activity followed by a sudden reduction of activity. The high sympathetic activity associated with SAS may be important in the development of the systemic hypertension commonly seen in these patients.

Blood Pressure↗
PubMed1988

Acute effects of short-term fasting on blood pressure, circulating noradrenaline and efferent sympathetic nerve activity.

Eleven moderately obese women, aged 46-62 years, with a body mass index of 29-34 and with borderline hypertension (repeated diastolic blood pressure greater than 90 mmHg) fasted for 48 hours. Before the fast and after 48 hours of fasting, plasma noradrenaline, urinary noradrenaline, urine potassium, urine sodium and weight were measured. In six of the patients muscle nerve sympathetic activity was recorded from the peroneal nerve by tungsten microelectrodes for 15 min each time. The efferent muscle sympathetic activity (MSA) was expressed as the number of bursts/min. The recordings were done before the fast and after 48 hours of fasting. We found significant decreases in body weight from 88.4 +/- 2.5 kg to 86.4 +/- 2.5 kg. Systolic blood pressure (BP) was reduced from 158 +/- 3 mmHg to 146 +/- 5 mmHg (p less than 0.001) and diastolic BP from 96 +/- 3 mmHg to 89 +/- 3 mmHg (p less than 0.01) during the fast. MSA was significantly increased from 42.0 +/- 5.5 bursts/min to 44.5 +/- 5.8 (n = 6), while plasma and urine noradrenaline concentrations (n = 11) showed a non-significant tendency to increase. We conclude that the hypotensive response during the first days of extensive caloric reduction is not due to a decreased sympathetic activity. If anything, there may be weak increase of efferent sympathetic nerve activity and venous plasma levels of circulating noradrenaline. The mechanisms behind the acute hypotensive response to negative caloric balance are thus still unclear, but obviously different from long-term adaptation of the blood pressure.

Blood Pressure↗
PubMed1988

Influence of intraperitoneal anesthesia on pain and the sympathoadrenal response to abdominal surgery.

The effects of intraperitoneal administration of bupivacaine on pain and the sympathoadrenal response to surgery were studied in a double-blind randomized trial in 19 patients undergoing cholecystectomy. Bupivacaine (2 mg/kg) was dissolved in 300 ml isotonic saline and administered into the peritoneal cavity 10 min before the operation (n = 9). Saline was administered in a comparable group of patients (n = 10). There were no significant differences in pain scores between the groups during the first day after surgery (P greater than 0.05). Postoperative requirements of pethidine during the first 2 days after surgery did not differ significantly between the groups. Blood glucose levels were significantly lower in the bupivacaine-treated group 1 h (P less than 0.05) and 4 h (P less than 0.05) after skin incision. No significant differences were observed between the groups regarding plasma catecholamine and serum cortisol levels during and after surgery. Differences between the groups regarding urine output of catecholamines during the first and second postoperative days were not significant. Our results suggest that single administration of a local anesthetic intraperitoneally does not reduce pain or the sympathoadrenal response to upper abdominal surgery.

Adrenal Medulla↗
PubMed1988

Isolation and structural characterization of thymosin-beta 4 from a human medullary thyroid carcinoma.

An extract of a tumour metastases from a human medullary thyroid carcinoma contained a high concentration (at least 2.9 nmol/g wet weight) of the immunoregulatory peptide, thymosin-beta 4. The peptide was isolated as a mixture of two components with free and blocked NH2-terminal amino acid residues, the latter form predominating (approximately 98% of the total). The primary structure of the peptide was established by automated Edman degradation after cleavage with cyanogen bromide. The amino acid sequence of human thymosin-beta 4 was identical to thymosin-beta 4 previously isolated from calf thymus. Further studies are warranted to determine whether thymosin-beta 4 production is a useful marker for thyroid and other tumours.

Adult↗
PubMed1988

Sensory thresholds in the male urethra measured by electrical stimulation.

The sensory pathways innervating the male urethra were investigated by recording the sensory thresholds with electrical stimulation. Twenty-six male subjects (age 16 to 73 years) were included in the study. Ring-electrodes mounted on a Foley catheter were used for stimulation in proximal and distal urethra. Square wave pulses (duration 0.5 ms) were delivered with a constant current stimulator at different frequencies and the lowest intensity felt by the subject was defined as the threshold. The sensory thresholds were in the order of 0.5 to 5 mA and decreased with increasing stimulation frequency. All patients described a qualitative difference in the experienced sensation when comparing proximal and distal urethral stimulation. The reason for this is discussed. The possible use of this method as an adjunct to the urodynamic investigation in diagnosing neurogenic lesions is proposed.

Adolescent↗
PubMed1988

Nuclear DNA content and prognosis in Hürthle cell tumours of the thyroid gland.

The prognostic value of nuclear DNA content in Hürthle cell tumours of the thyroid was studied in 23 patients with more than 10 years follow up. Eleven of these neoplasms were classified as Hürthle cell carcinoma and 12 as adenoma. DNA measurements in morphologically identified single tumour cells were performed either on fine needle aspiration biopsy material or on histological sections from the primary tumours. The nuclear DNA content identifies those patients with a good versus a bad prognosis. These results correlate well with the findings in earlier studies about papillary, follicular and medullary thyroid tumours.

Adenoma↗
PubMed1987

Multimodality treatment in anaplastic giant cell thyroid carcinoma.

Anaplastic giant cell thyroid carcinoma is highly malignant. Surgery, chemotherapy, or radiotherapy used separately have not been effective. Combinations of the three modalities have been used at Radiumhemmet since the middle of the 1970s. Nine patients received three-drug chemotherapy and radiotherapy. One patient was alive after 12 years; eight died. Twenty-five patients were given a similar regimen (with two fractions of radiotherapy per day), aiming at surgery. Twelve patients could undergo surgery. Two were alive 11 and 3.5 years after diagnosis. One patient died free of tumor after 6.5 years. Of the remaining 22 patients, many died of metastatic disease. A combination of preoperative and postoperative radiotherapy, chemotherapy (bleomycin, cyclophosphamide, and 5-fluorouracil) and surgery during the remission has given a 12% (four of 34) survival (greater than 3 years). All survivors had undergone surgery. The patients who died had in many cases achieved local tumor control. Adriamycin (Adria Laboratories, Columbus, OH) once a week replaced BCF due to treatment complications in patients receiving BCF. Of five patients, only one was alive more than 10 months after treatment.

Bleomycin↗
PubMed1987

Fine-needle biopsy cytology and DNA analysis. Their place in the evaluation and treatment of patients with thyroid neoplasms.

Fine-needle aspiration allows sampling of tissues without surgical biopsy. This technique provides accuracy, speed, patient acceptance, and individual cells for the study of neoplasia. When this procedure is combined with DNA analysis, it is possible to obtain preoperatively additional diagnostic and prognostic information superior to that obtained by clinical and morphologic methods alone. This information is of utmost importance when planning appropriate treatment.

Biopsy, Needle↗
PubMed1987

Effects of lidocaine infusion on the sympathetic response to abdominal surgery.

Activation of afferent nerves in the area of surgery is a cause for surgical pain and stress. Intravenous (IV) lidocaine has been shown to inhibit postoperative pain. In the present double-blind study, the effects of a continuous IV infusion of lidocaine (2 mg/min) on the sympathoadrenal stress response to surgery were evaluated in 38 patients scheduled for elective cholecystectomy who were randomly assigned to two groups. In one group, lidocaine infusion was started 30 min before the operation and continued for 24 hr after surgery (n = 18). In the second group (n = 20), saline was infused. The increases in heart rate and blood pressure after tracheal intubation were not significantly different between the groups, but tachycardia and hypertension associated with extubation was prevented in patients given lidocaine. Differences in blood pressure and heart rate between the two groups were otherwise not significant intra- or postoperatively, nor were differences in blood glucose or plasma catecholamine concentrations during the first 24 hr after skin incision. Urinary catecholamine concentrations did not differ significantly in the two groups during the first postoperative day, but during the second postoperative day urinary output of epinephrine and norepinephrine were significantly less in the group of patients receiving lidocaine infusion. It was concluded that the IV infusion of lidocaine during and after major abdominal surgery suppresses extubation-induced hypertension and tachycardia but does not inhibit the general sympathetic response during the first postoperative day. However, lidocaine infusion reduces urinary output of catecholamines during the second postoperative day, suggesting a more rapid decline in the sympathoadrenal response postoperatively in the experimental group.

Adrenal Medulla↗
PubMed1986

Low molecular weight heparin once daily compared with conventional low-dose heparin twice daily. A prospective double-blind multicentre trial on prevention of postoperative thrombosis.

In a randomized, prospective, double-blind multicentre trial, the effect of conventional low-dose heparin 5000 units twice daily, was compared with that of a low molecular weight heparin fragment (4000-5000) 5000 anti-factor Xa units once daily. Four hundred and thirty-two patients fulfilled the inclusion criteria and were analysed for development of deep vein thrombosis (125I-labelled fibrinogen test) and haemorrhagic complications. Thrombosis occurred in a 4.3 per cent of patients in the low-dose heparin group and in 6.4 per cent of patients in the heparin fragment group, a difference which is not significant. There was a significant delay in the onset of thrombosis in the heparin fragment group. Mortality did not differ between the groups, nor did peroperative blood loss or transfusion requirements or infectious complications. Haemorrhagic complications occurred significantly more often in the fragment group (11.6 per cent) than in the conventional heparin group (4.6 per cent). Patients in the heparin fragment group experienced local pain following the subcutaneous injection significantly less often.

Adult↗
PubMed1986

Abnormalities of sympathetic regulation after cervical cord lesions.

Microneurographic recordings suggest that hypertensive reactions in patients with cervical spinal cord lesions usually are due, not to exaggerated sympathetic nerve reactions, but rather to the combination of more diffuse sympathetic nerve activation than normally, exaggerated vascular reactions and absence of blood pressure restraining reflexes.

Humans↗
PubMed1986

Effect of intra-abdominal bupivacaine instillation on postoperative colonic motility.

Effect of intra-abdominal instillation of a local anaesthetic, bupivacaine, on postoperative colonic adynamic ileus was studied in a double blind manner in a randomised series of patients undergoing upper laparotomy. Propulsive colonic activity was studied postoperatively with radio-opaque markers and serial abdominal radiographs. Intra-abdominal instillation of bupivacaine 2 mg/kg bw significantly shortened the period of postoperative colonic inhibition (p less than 0.01), but did not hasten colonic transit. Furthermore, bupivacaine significantly decreased the hyperglycaemic response to surgery. It is suggested that bupivacaine inhibits the inflammatory response within the bowel wall, a response which may maintain the inhibitory spinal reflexes in the postoperative period. Blood concentrations of bupivacaine were shown to be well below toxic levels and no adverse reactions were observed.

Abdomen↗
PubMed1986

Prospective double-blind comparison between Fragmin and conventional low-dose heparin: thromboprophylactic effect and bleeding complications.

In a randomized, prospective, double-blind multicenter trial, the effect of low-dose conventional heparin (5,000 IU/12 h) was compared to a low molecular weight (LMW) heparin fragment (5,000 antifactor Xa U/24 h). 432 patients 40 years or older undergoing elective abdominal surgery were included, 382 correctly treated. 45% had malignant diseases. The groups did not differ in risk factors. Analysis was made both on the basis of intention to treat and correct prophylaxis. No difference in results between these 2 groups was seen. Deep vein thrombosis (125I-fibrinogen) occurred in 4.3% of the low-dose heparin group and in 6.4 of the LMW heparin group. There was a significant delay in the onset of deep vein thrombosis in the LMW heparin group. Mortality, peroperative blood loss, transfusions or infectious complications did not differ. Hemorrhagic complications occurred significantly more often in the LMW heparin group (11.6%) than in the low-dose heparin group (4.6%). Significantly fewer patients experienced local injection pain in the LMW heparin group. APTT and AT III were similar in both groups, but anti-Xa activity was significantly higher in the LMW heparin group. Single daily LMW heparin injection reduced the frequency of deep vein thrombosis to the same level as low-dose heparin twice daily. The dose or administration interval of LMW heparin in this study caused significantly more bleeding complications.

Aged↗
PubMed1986

Failure of epidural anesthesia to prevent postoperative paralytic ileus.

This study used radiopaque markers and serial abdominal radiographs to assess the effect of epidural anesthesia on postoperative colonic ileus. Epidural anesthesia did not result in significantly faster return of propulsive motility in the colon after surgery as compared with control (P greater than 0.05). In addition, no significant difference was seen between the groups in colonic transit time and time for the first passage of gas and feces. The level of inhibition of sympathetic efferent nerves to the abdominal cavity was assessed by repeated measurements of blood glucose levels during the first postoperative day. Blood glucose levels were found to be significantly lower in the epidural group, demonstrating an inhibition of efferent sympathetic nerves below the level of T-5. Results show lack of effect of continuous epidural anesthesia in the prevention of postoperative paralytic ileus and suggest that mechanisms other than spinal reflexes play a major part in the development and maintenance of intestinal paralysis.

Anesthesia, Epidural↗
PubMed1985

Effects of regional intravenous guanethidine block in posttraumatic cold intolerance in hand amputees.

In twenty-four patients with intolerance to cold after partial or complete finger amputations, lower skin temperature together with cold and vibration allodynia (allodynia = pain due to a non-noxious stimulus to neural skin) were found in the cold intolerant area compared with the corresponding area in the uninjured hand. When treated with regional intravenous guanethidine block nine patients became free from symptoms for up to twelve weeks, which is longer than would be expected from the duration of the known pharmacological effects of guanethidine. The patients had several features in common with reflex sympathetic dystrophies, and we suggest that neurogenic rather than vascular disturbances are mainly involved in the post-traumatic cold intolerance syndrome.

Adult↗
PubMed1985

Inhibition of postoperative pain by continuous low-dose intravenous infusion of lidocaine.

Intravenous lidocaine has been reported previously to inhibit postoperative pain when given either as single injections or as short infusions in amounts usually causing adverse reactions. To determine the efficacy of a continuous low-dose (2 mg/kg) intravenous infusion of lidocaine, postoperative pain (visual analogue pain scale) and the requirements for postoperative analgesics were measured in a double-blind randomized trial in 20 patients after cholecystectomy. Lidocaine infusion was started 30 min before the operation and continued for 24 hr after surgery (n = 10). Saline was infused in a comparable group of ten patients. The lidocaine-treated patients had significantly lower pain scores during the first day after surgery (P less than 0.001) and required significantly less meperidine during the first (P less than 0.02) and second postoperative days (P less than 0.01). No adverse reactions to lidocaine were observed. Whole blood levels of lidocaine ranged between 1 and 2 micrograms/ml. The results suggest that low-dose continuous infusions of lidocaine decrease the severity of postoperative pain and are devoid of side effects.

Adult↗