Biomedical subjects

L N van Adrichem

Publications and source records attributed to L N van Adrichem.

9 recordsLinked to original sources

PubMed2001

The nasal dorsum as a donor site for the correction of alar, lobular, and columellar malformations.

There is a wide variety of donor sites available for minor nasal reconstructions involving alar, lobular, and columellar defects. Unfortunately, the problems all these sites have in common are that the color match may be unsatisfactory or that the end result may be marred by conspicuous scarring. If nasal-skin resources could be fully exploited, the elimination of these two important problems could become an obtainable goal. This article discusses the potential of the nasal dorsum as a donor site and describes methods that were used to try to achieve this goal. Skin redistribution, skin expansion, and skin distraction methods were used in 28 patients with alar (n = 13), lobular (n = 8), and columellar (n = 7) malformations and who had been followed up since the early 1980s.

Adolescent↗

PubMed1996

The effect of cigarette smoking on the survival of free vascularized and pedicled epigastric flaps in the rat.

Microsurgeons suspect that cigarette smoking reduces the survival of free vascularized flaps and replantations, but this has never been proven. This experimental study investigates the effect of smoking on free-flap survival. A fasciocutaneous epigastric flap was used in 30 rats as a free flap and in 30 rats as a pedicled flap. Of each group, 10 rats were smoked 6 weeks before and 2 weeks after surgery, 10 rats were smoked only 6 weeks before surgery, and 10 rats underwent the sham smoking procedure. Also, a distally based dorsal skin flap was cut in all rats, representing a random vascularized flap. Vitality and size of both flaps and patency of the vascular anastomoses were assessed 14 days after surgery. The epigastric flaps were monitored by laser Doppler flowmetry and thermometry during the experiment. Survival of the free vascularized epigastric flaps was significantly lower in smoking rats. All pedicled flaps except one survived. The epigastric flaps only necrosed or survived completely, exactly correlating to the patency of the vascular anastomoses. The mean surviving area of the dorsal flaps was best for nonsmoking rats, worse for only preoperatively smoking rats, and worst for preoperatively and postoperatively smoking rats. The differences were statistically significant. Postoperative laser Doppler flow differed significantly between surviving and dying flaps, affirming the value of laser Doppler flow monitoring in microvascular surgery. In conclusion, this study proves that smoking of cigarettes is detrimental to the survival of free vascularized flaps.

Anastomosis, Surgical↗

PubMed1995

Comparison of laser Doppler flowmetry and thermometry in the postoperative monitoring of replantations.

Reliable postoperative monitoring in microvascular surgery is necessary to improve the success rate of reexplorations following vascular compromise. Surface thermometry is known as an easy and inexpensive objective postoperative monitor and therefore is used by many microsurgeons. Reliability, however, is not satisfactory, and therefore several other instrumental methods have been tested of which laser Doppler flowmetry shows the most promising results. This study compared laser Doppler flowmetry to thermometry in the postoperative monitoring after replantation surgery. In 34 patients, 45 replantations and revascularizations were monitored by laser Doppler flowmetry and thermometry. A reliable alarm value of 10 PU was defined for replantations and revascularizations, with a sensitivity of 93% and a specificity of 94%. Thermometry showed a sensitivity of 84% and a specificity of 86% at 29 degrees C.

Adolescent↗

PubMed1993

The predictive value of the laser Doppler flowmeter for postoperative microvascular monitoring.

Reliable postoperative monitoring in microvascular surgery is necessary to improve the low success rate of reexploration after vascular compromise. The use of laser Doppler flowmetry has been evaluated in this study. From November 1985 to January 1988, 79 microvascular operations were monitored postoperatively. These consisted of 45 replants and revascularizations in 34 patients, as well as 34 free vascularized tissue transfers. In the replant and revascularization group, a statistically significant difference in laser Doppler flowmetry readings has been demonstrated between well-vascularized and circulatory impaired patients (p < 0.001). In this study a reliable critical (alarm) value could be defined for replants and revascularizations with a sensitivity of 93% and a specificity of 94%. This critical alarm value can be adjusted according to the individual surgeon's attitude toward reexploration. Similar laser Doppler flowmetry characteristics were seen in patients with free vascularized tissue transfers; however, the numbers in this part of the study were too small to define reliable critical alarm values. The laser Doppler flowmeter is recommended for the postoperative evaluation of tissue after microvascular anastomoses, as it indicates vascular occlusion at an early stage where reexploration is worthwhile.

Adolescent↗

PubMed1993

Differences between arterial and venous occlusion in microvascular surgery.

Between November 1985 and November 1988 11 patients developed arterial occlusion after microvascular anastomoses, 10 patients venous occlusions and five combined arterial and venous occlusions. We undertook a retrospective study to see whether colour, capillary refill, thermometry, or laser Doppler measurements could distinguish arterial and venous occlusions. Neither skin thermometry nor total backscattered light intensity change and flow band width (laser Doppler measurements) were significantly different (p > 0.05) between arterial and venous occlusions, but there were significant differences in colour (p = 0.006), capillary refill (p = 0.007), and laser Doppler flow (p = 0.02). The values obtained from cases with combined arterial and venous occlusions were like those of a venous occlusion or of an arterial occlusion or somewhere in between. Although none of the variables was diagnostic, we advise that the suspect vascular anastomosis should first be checked during reoperation. If an occluded anastomosis is found, one should also check the other anastomosis because occlusion of both artery and vein cannot be reliably detected.

Anastomosis, Surgical↗

PubMed1992

Acute effects of cigarette smoking on microcirculation of the thumb.

The acute effect of smoking on the microcirculation of the skin of the thumb was investigated in healthy volunteers. Twenty-two were smokers and 10 were non-smokers. The flow was assessed by means of laser Doppler flowmetry. The smokers inhaled 2 cigarettes. During smoking of their first and second cigarette respectively, a mean decrease in laser Doppler flow of 23.8% and 29.0% was seen (p = 0.03; p = 0.01). Ten minutes after smoking this decrease was recovered by half. This experiment confirms that one should prohibit smoking of cigarettes pre- and postoperatively for optimal wound healing conditions.

Adolescent↗

PubMed1992

The acute effect of cigarette smoking on the microcirculation of a replanted digit.

Thirty-one patients who had undergone digital replantation or revascularization volunteered to participate in a study of the acute effect of smoking on the microcirculation of the skin of replanted fingers. Fourteen were smokers and 17 were nonsmokers at the time of the study. Blood flow was assessed by means of the laser Doppler flowmeter under standard conditions. Each smoker inhaled 2 cigarettes. During smoking of the first and second cigarettes a mean decrease in laser Doppler flow of 8% and 19%, respectively, was found, whereas the nonsmokers showed a slight increase of 4% and 4%, respectively. Ten minutes after the last cigarette almost no recovery could be detected. The negative effect of smoking on the microcirculation in replanted digits proved to be more pronounced in the patients operated on more recently. This experiment confirms that smoking after replantation surgery should be prohibited to guarantee optimal circulation.

Adult↗

PubMed1991

The femoro-femoral cross-over bypass.

From 1984 to 1990 64 patients (56 men and 8 women) with a mean age of 67.1 years (36-88 yrs.) were treated with a femoro-femoral cross-over bypass (45 primary and 19 secondary procedures). All patients had an occlusion of one iliac artery. In 26 patients there were factors that made a central reconstruction unattractive. These disorders were congestive heart failure, COPD, CVA, an age over 80 years, etc. In 19 patients an occlusion of one leg of a former aortobifemoral bypass determined the choice for cross-over bypass. Three patients died (5 per cent), two patients of the so-called redo-group (septicaemia, one patient and arteriojejunal fistula one patient), the third patient died after a primary femoro-femoral bypass (myocardial infarction). The overall patency rate after three years was 78 per cent. Especially primary cross-over bypasses showed a good outcome with a primary patency of 80 per cent and a secondary patency of 85 per cent after three years. Considering that 23 of the 45 (51 per cent) primary procedures were for treatment of critical ischaemia (stage III and IV of Fontaine), a favourable limb-salvage of 21 out of 23 (91 per cent) was obtained. The cross-over bypass can be recommended as first choice therapy for patients with a unilateral iliac artery occlusion.

Adult↗

PubMed1988

Postoperative monitoring of allogeneic limb transplantation in rats.

Allogeneic limb transplantation with and without immunosuppression has been successfully reported. We used the experimental model described by Fritz and colleagues to investigate the value of different factors in the rejection phase. Twenty rats of inbred strains sustained an allogeneic limb transplantation without immunosuppression. In 6 rats an isologous limb transplantation was performed as a control group. Factors investigated in the transplanted limb were glucose, lactic acid, and blood gases of the peripheral blood, as well as laser Doppler flowmeter (LDF) recordings and histology. All factors were compared with the normal contralateral limb of the rat. All rats were killed between days 2 to 14 following operation. In the allogeneic limb transplantation model in the rat, clinical and histological examination as well as LDF measurements (p less than 0.0001) are good factors for rejection. In contrast, peripheral blood gases, glucose, and lactate were not useful as factors for rejection. In this model, however, LDF values cannot predict an initial onset of the rejection before clinical signs are evident, presumably because of the impossibility of continuous measurements.

Animals↗