Jan Eklund

Serum steroids and prolactin during and after major surgical trauma.

Serum levels of cortisol, dehydroepiandrosterone (DHA) and its sulfate (DHAS), 4‐androstene‐3,17‐dione (A‐4), 17‐alfa‐hydroxy‐progesterone (17 OHP), testosterone (T, only in males), unconjugated (E1) and total estrone (tE1 >85% estrone sulfate) were studied in six male and two female patients before, during and up to 30 days after aortic graft surgery. All steroids except 17 OHP decreased following induction of anesthesia but, except for testosterone, rose again during surgery to preoperative levels or slightly above. Extremely high peak values for El and tE1 and a less pronounced peak for cortisol were noted on postoperative day 2; after that, the levels of these steroids returned to normal. The levels of 17‐OHP, DHA and DHAS decreased after surgery and were below preoperative values from postoperative day 4 to day 16 or (DHAS) day 30. In males, 17 OHP showed a pronounced peak 30 min after initiation of surgery, but decreased after that to below preoperative values. Testosterone levels decreased further during surgery and remained very low until postoperative day 16. Major surgical trauma has a rapid, profound and long‐lasting effect on gonadal activity, as judged from decreased testosterone levels, while the effect on adrenal steroids is less pronounced. Adrenal Δ4 and Δ5‐steroids showed different patterns in the postoperative period, indicating differences in their regulation. The highly elevated estrogen levels on postoperative day 2 probably reflect either transiently elevated peripheral aromatization or decreased estrogen metabolism rather than increased levels of substrate steroids (A‐4).The biological significance of this remains to be elucidated.

Lipid infusion in critically ill patients: Acute effects on hemodynamics and pulmonary gas exchange

Hemodynamics, pulmonary diffusing capacity (DLco) blood gases, oxygen consumption (Vo2) and carbon dioxide excretion (Vco2) were studied in healthy volunteers and ventilator-treated, critically ill patients before and during infusion of lipid emulsion for 4 h. Triglyceride levels rose from 1.0 mmole/L to 8.5 mmole/L in the volunteers and from 1.4 mmole/L to 6.3 mmole/L hi the patients after 4 h. No adverse effects on cardiovascular performance were observed. Increases in Vo2, and Vco2 and cardiac output were found m both groups, while RQ remained constant. No changes hi DLco and blood gases occurred.

PREOPERATIVE INFILTRATION OF BUPIVACAINE-EFFECTS ON PAIN RELIEF AND TRAUMA RESPONSE (CORTISOL AND INTERLEUKIN-6)

Hypothesis: Subcutaneous infiltration of bupivacaine before skin incision can reduce postoperative pain and modulate the stress response.

Uteroplacental blood flow measured by placental scintigraphy during epidural anaesthesia for caesarean section

The uteroplacental blood flow was measured before and during epidural anaesthesia for caesarean section in 11 women. The blood flow was measured with dynamic placental scintigraphy. After an i.v. injection of indium‐113m chloride, the gamma radiation over the placenta was recorded with a computer‐linked scintillation camera. The uteroplacental blood flow could be calculated from the isotope accumulation curve. The anaesthesia was performed with bupivacaine plain 0.5%, 18–22 ml and a preload of a balanced electrolyte solution 10 ml/kg b.w. was given. The placental blood flow decreased in eight patients and increased in three with a median change of – 21%, not being statistically significant. No correlation between maternal blood pressure and placental blood flow was found.

The effect on uteroplacental blood flow of epidural anaesthesia containing adrenaline for caesarean section.

The effect on uteroplacental blood flow of an epidural anaesthesia containing adrenaline for caesarean section was investigated in ten healthy women using dynamic placental scintigraphy with indium‐113m and a computer‐linked gamma camera. The epidural anaesthesia was performed with 18–22 ml bupivacaine 5mg/ml with adrenaline 2.5 μg/ml followed by an i.v. balanced electrolyte infusion of 10 ml/kg b.w. A significant median decrease in the total maternal placental blood flow of 34% was found (P<0.01). There was also a significant decrease in maternal mean blood pressure of 3 mmHg (0.4 kPa) (P<0.05) and a significant negative correlation between the change in maternal blood pressure and the change in uteroplacental blood flow (r= –0.69, P<0.05).

Pronounced Dyslipoproteinemia in Intensive Care Patients

Concentrations of triglycerides (TG) and cholesterol in serum and in lipoproteins were determined in two groups of intensive care patients. Group I included 17 moderately ill, postelective surgery patients, and group II, 23 critically ill patients. All were studied in an intensive care situation. The lipoprotein lipid concentrations were compared with those from a group of healthy men and women. In group I, both TG and cholesterol concentrations in serum were decreased, whereas in group II, only cholesterol concentration was lowered and the TG concentration was close to control values. In the lipoproteins, marked abnormalities were found. The most striking was an increase in low density lipoprotein (LDL)-TG and a decrease in high density lipoprotein (HDL)-cholesterol concentrations. In group II, 5/18 males had a LDL-TG concentration above any control value and 21/23 had a HDL-cholesterol concentration below any value in the control group. In addition, the alpha-lipoprotein (HDL) band on electrophoresis was often grossly abnormal with a broad or double-peaked band. There was a highly significant negative correlation between LDL-TG and HDL-cholesterol concentrations. Patients who received conventional treatment with insulin or heparin had similar lipid concentrations as those not given these drugs. The time effect on lipoprotein changes was analyzed in 11 patients, from whom samples were drawn repeatedly during the intensive care period. A tendency was found for LDL-TG to increase and HDL-cholesterol to decrease with time. The mechanisms causing the lipoprotein changes are not presently known; however, possible explanations include liver function impairment, gastrointestinal tract paralysis, physical inactivity, the catabolic state as such, and combinations.

Infiltration of morphine into an abdominal wound; effects on pain relief and endocrine/immune response

&NA; We wanted to evaluate pain relief and endocrine /immune response after local administration of morphine into an abdominal wound. In a randomised double blind design 29 patients undergoing hysterectomy received two blinded injections of morphine and saline. Before surgery the patients in the control group (n=15) got 10 mg of subcutaneous morphine into an arm and at skin incision 30 ml of saline was infiltrated directly into the wound. The patients in the wound group (n=14) received 1 ml of saline into an arm before surgery and 10 mg of morphine in 30 ml of saline into the wound at skin incision. Patient controlled analgesia (PCA) with i.v. morphine was used after surgery. Repeated blood samples were obtained from the day before the surgery until 3 days later and analysed for cortisol and interleukin‐6 (IL‐6). There were no differences between the groups either in pain relief or in the consumption of PCA morphine. The wound group used 47±15 mg of i.v. morphine and the control group used 50±16 mg. Peak values for IL‐6 and cortisol appeared at 4 h. The area under the curve (AUC) of cortisol at 0–6, 0–10 and 0–20 h was significantly lower in the control group than in the wound group (P<0.05). High doses of i.v. morphine reduced cortisol and IL‐6 levels in the early hours after surgery. The injection of morphine into the wound did not improve pain relief or reduce the consumption of i.v. morphine after surgery. The endocrine stress response to trauma was modified by preoperative administration of morphine.

Plasma catecholamine and free fatty acid levels during infusion of lipid emulsion in critically ill patients.

The fractional elimination rate of exogenous fat, and fat-mobilizing lipolysis in relation to plasma catecholamine (CA) levels were studied in seven ventilatortreated ICU patients. Blood levels of CA, triglycerides, cholesterol and free fatty acids (FFA) were also analyzed before and during constant infusion of a soybean oil emulsion (Intralipid). Triglyceride concentrations rose significantly during the infusion. FFA levels also increased significantly within 30 min after the infusion was begun, reflecting fatty acids derived from Intralipid triglycerides. Plasma norepinephrine levels showed large interindividual variations and were inversely related to FFA concentrations. No correlation was found between plasma CA levels and the fractional removal rate of fat. These data suggest a deficiency of substrate in these critically ill patients.

Impressions for prosthodontic restorations reproducing narrow spaces and severe undercuts

Distortion of an impression material may occur in special clinical situations in which the materials elastic limit is exceeded. Impressions were made of a master model designed to test such situations. Three different hydrocolloids and an addition silicone were used in the experiment. An extended setting time had to be used for one material, to prevent it from tearing. When this extended time was used, this material was the dimensionally most accurate material in the test. All materials were accurate in reproducing normally positioned abutments, while some of the impressions failed to reproduce adjacent abutments with particularly narrow interspaces; narrow passages may therefore require further tooth preparation. In the most severely undercut area differences existed among the materials, and sometimes tears occurred. When the papilla is missing, the undercut area should be blocked out to prevent plastic deformation of the impression material, causing inaccurate restorations.

Proper and accurate use of references

Precision in the preparation of a manuscript is thc duty of both the author and the editor. Just as it is self-evident that the scientific part should be faultless, precision also should be the natural goal when it comes to the formal production of a manuscript. Onc part of this obligation involves the proper use of references. In this issue of Acta Anaesthesiologica Scandinavica, Nishina and colleagues (1) bring one problem of this kind to our attcntion, namely the accuracy of the bibliographic elements of the reference list. In a study of two samples from recent volumes of AAS they have shown that, as measured from 6 chosen bibliographic parameters, 40-45”/0 of the references contained at least one error. Naturally this is an unacceptably high frequency, but two facts console us. Firstly, the majority of the errors they found were mistakes concerning the title of thc manuscript and the names of the authors. No matter how impolite such errors may seem, it was ~ in most cases still possible for the reader to identify the refercnce in question from the name and volumc of the journal, and the year of publication. Errors of these types were distinctly less frequent. This is in concordance with the report of Todd and Warner (2) who, in another search, were able to retrieve more than 98‘Yo of a given sample of references. Secondly, we learn from the study of McLellan, Casc and Barnct (’3) that the frequency of errors is about the same as in other major journals within anaesthesiolo,q. Nevertheless, it is still unacceptable that errors exist at such a high frequency, and wc urge our contributors to focus their attention also on this part of the preparation of their manuscripts. However, therc is another and much more difficult problem that of the relevance of a certain refermcc. According to the unwritten rules of scientific publishing, appropriate references should be given when data, ideas and \riews from othcr sources are used. Of course, it is takcn for granted that the referral is not only technically correct but, more important, also scientifically correct. The results and conclusions of other scientists should be quoted in an unbiased way; priorities should be honoured and the citation should never be detached from the original context. If these rules are breached or neglected, the scientific community must react. This serious problem was brought up by ftiebuck in his editorial comment (4) to the paper of McLellan et al. (3). This editorial deserves to be carefully rcad by all scientists -junior and senior. Biebuck also cites Stcwart and Feder who divided the errors of referring into those of type A and type B (5). Type A errors can be explained simply by carelessness and/or rxcessive haste, such as the bibliographic errors found in the prescnt study. Typc B errors are the much more serious ones like deliberately misleading citations or missing citations (failure to acknowledge a source). Biebuck also quotes the important and &stressing observation of Hirschmann that bibliographic errors sometimes may be traced from source to sourcc back to an original mistake, strongly indicating that none of the authors checked the original paper. If a mistake or a misinterpretation is made early in this chain it could easily assume the status of a demonstrated fact when rcpeated often enough (6). How honest citing is to be guaranteed is a matter of major concern to every editorial board. Maybe somc readers imagine that controlling this is a compulsory part of the editing process, but on closer consideration it should be easily understood that this is virtually impossible unless resources are “unlimited”. Naturally everything possible is done, but not cvcn the peer reviewers who, by definition, should be well informed about the objectives of a certain manuscript can actually be asked to evaluate the correct use of references. Apart from the scicntific difficulties, the task would be too rcsource consuming. Thus the scientific community and its journals must rely on the members of the society. It must be a professional obligation of the highest degree to the individual scientist to “write and cite” nothing but the truth, and to present her/his message in an unbiased way. If this is not donc and the fault is not revealed during the editorial process, it should be the obligation of anyone who discovers a mistake of this kind to make it public. This is easily done through a letter to the editor, the publication of which should reasonably lead to a fruitful debate of mutual interest. It is, however, surprisingly seldom that we receive reactions of this kind and one may speculate upon the