PubMed Health⌕ Search

Biomedical subjects

S O Waller

Publications and source records attributed to S O Waller.

8 recordsLinked to original sources

Long-term changes in muscle free amino acid levels after elective abdominal surgery.

Characteristic changes in the pattern of muscle free amino acids are seen on the third day after elective surgery. The time course of the restoration to normal levels in uncomplicated cases has not been established before. Seven metabolically healthy patients undergoing cholecystectomy were studied. Muscle biopsy specimens and plasma samples were taken before operation and on days 3, 10, 20 and 30 after surgery. The level of total free amino acids in skeletal muscle decreased and the concentrations of branched chain and aromatic amino acids increased on day 3. The original levels were found to be restored on day 10 after surgery. A decrease in glutamine of 38 per cent (P less than 0.001) was seen on day 3, of 20 per cent (P less than 0.05) on day 10 and of 22 per cent (P less than 0.05) on day 30, compared with preoperative values. These results constitute a baseline for future studies in which the impact of nutritional and pharmacological therapies is to be evaluated beyond the immediate postoperative period.

Amino Acids↗

Elective abdominal surgery depresses muscle protein synthesis and increases subjective fatigue: effects lasting more than 30 days.

Ten patients without metabolic disease undergoing elective cholecystectomy were studied before surgery and on days 3, 10, 20 and 30 after operation. Percutaneous muscle biopsies were taken and protein synthesis was determined from the total concentration and size distribution of ribosomes. The subjective feeling of fatigue was estimated using a visual analogue scale. The nitrogen balance was calculated at 20 days following surgery. The mean (s.e.m.) total concentration of ribosomes per milligram of DNA decreased by 27.5(6.6) per cent (P less than 0.01), 44.5(6.5) per cent (P less than 0.001), 48.3(8.9) per cent (P less than 0.001) and 45.0(8.2) per cent (P less than 0.01) on days 3, 10, 20 and 30, respectively. By 30 days after surgery no sign of restoration of normality was seen. The relative proportion of polyribosomes had decreased by 20.4(6.4) per cent (P less than 0.05) on the third postoperative day and by 20.4(3.9) per cent (P less than 0.01) on the tenth postoperative day and was restored to the preoperative level by day 20. The subjective fatigue score increased after operation and five of nine patients had not regained their preoperative scores 30 days after surgery. The daily nitrogen balance was negative for 5 days. The cumulated nitrogen losses were not restored until after 18 days following surgery. Elective abdominal surgery caused a sustained depression of protein synthesis for over 30 days, a longer period than previously presumed. These results show that long-term follow-up is required when the effect of different postoperative nutritional regimens are to be evaluated.

Cholecystectomy↗

Long-term effect of glycyl-glutamine after elective surgery on free amino acids in muscle.

In order to evaluate the long-term effect of total parenteral nutrition supplemented with glutamine after surgery, patients (n = 17) undergoing elective abdominal surgery were randomized into two groups and studied for 30 days after surgery. During the 3 days immediately after surgery, one group (n = 8) was given total parenteral nutrition including a conventional amino acid solution (control group). The other group (n = 9) was given isocaloric and isonitrogenous total parenteral nutrition including the same amino acid solution supplemented with the dipeptide, glycyl-glutamine (GLN group). Oral food intake started on the third postoperative day and was gradually increased at will. The concentration of free amino acids in percutaneous muscle biopsy specimens was determined preoperatively and on days 3, 10, 20, and 30 after the operation. Free glutamine decreased in skeletal muscle in the control group on days 3 and 10 by 32.2 +/- 5.4% (p < .01) and 20.1 +/- 6.9% (p < .05), respectively. In the glycyl-glutamine group, the decrease in glutamine was delayed until day 10 when it was 22.1 +/- 8.1% (p < .05). The glutamine levels were restored on days 20 and 30 in both groups. Total parenteral nutrition supplemented with glutamine maintained the free glutamine levels in skeletal muscle after surgery, but when treatment was discontinued, the glutamine concentration in muscle dropped, despite a normal enteral dietary intake.

Amino Acids↗