[Results of vascular surgery in the very old. Costs are comparable to those of younger patients]

An increasing number of very old patients are treated in hospitals but there are few Swedish studies of the results of the treatment. In this study the results and costs of vascular surgery in octogenarians were compared to those of younger patients. All Swedish patients treated in 1996 (10,185 procedures) were analyzed; one fifth were over 80 years of age. During the past ten years the number of procedures had increased 2.6 times in the old age group. The technical result, measured as patency rate one year after bypass surgery, was comparable in the two groups--73 per cent versus 81 per cent--but the mortality was higher in the older age group both in direct connection with the procedure and a year thereafter. The cost per procedure was not higher in the old age group.

The incidence of clinical postoperative thrombosis after gastric surgery for obesity during 16 years

BACKGROUND

Suggested risk factors for postoperative thrombosis such as high fatty acid levels, hypercholesterolemia and diabetes are common in obese patients.

METHODS

In a retrospective study, the case records of 328 patients operated for obesity by gastric procedure from September 1977 until December 1993 were analyzed: 253 women and 75 men with a mean age of 38 years and a mean body mass index (BMI) of 44 kg/m2. The operation time, use of epidural anesthesia, and the occurrence of risk factors; fatty acid levels, hypercholesterolemia and diabetes were recorded. Symptomatic thromboses were verified by phlebography or phlethysmography and pulmonary embolism with ventilation/perfusion scintigraphy or autopsy.

RESULTS

The mean operating time was 128 minutes, 77% had epidural anesthesia and the mean hospital stay was 12.3 days. The long hospital stay was due to the fact that most patients took part in different scientific studies perioperatively. The incidence of thromboembolism was 2.4%. Four patients had pulmonary embolism, in one of them this was fatal. Three patients had deep leg vein thrombosis and one patient had arm thrombosis secondary to a central venous catheter. None of these patients had high fatty acids, diabetes or high cholesterol. Of the patients, 298 were given dextran-70 (Macrodex, Pharmacia) as prophylaxis, seven were given heparin and 23 were given no prophylaxis. In the patient group without diagnosed thrombosis, 31% had high fatty acid levels, 2% had high cholesterol levels and 9% had diabetes.

CONCLUSIONS

Obese patients seem to have a moderate risk of developing postoperative thrombosis when an effective prophylaxis is used. High free fatty acids, hypercholesterolemia and diabetes are not obvious extra risk factors in obese patients. Thromboprophylaxis should be given to all operated obesity patients regardless of age. The surgeons must be aware and investigate promptly any symptoms suggestive of thromboembolism.

Risk factors for major thromboembolism and bleeding tendency after elective general surgical operations. The Fragmin Multicentre Study Group

OBJECTIVE

To elucidate those factors that contribute to the risk of major postoperative thromboembolism and perioperative bleeding tendency.

DESIGN

Retrospective multiple logistic regression analysis.

SETTING

7 Scandinavian hospitals (6 Swedish and 1 Norwegian).

SUBJECTS

2070 patients undergoing elective major abdominal surgery.

INTERVENTIONS

Patients were randomised to receive 2500 or 5000 XaI units of low molecular weight heparin daily.

MAIN OUTCOME MEASURES

Major thromboembolism (proximal deep vein thrombosis confirmed by phlebography or necropsy, or pulmonary embolism confirmed by scintigraphy or necropsy, or both). Bleeding tendency (bleeding complications which were not explained by local haemorrhagic lesions or by coexisting disease).

RESULTS

Previous thromboembolism, leg fracture or arthroplasty, present leg ulcer or malignant disease, operating time longer than 150 minutes, preoperative transfusion of 2 or more units, and preoperative hospital stay of 6 days or more (but not age, body weight, or varicose veins) were independent predictors for major postoperative thromboembolism. The risk was significantly increased with an increasing number of such risk factors. The risk of developing a diffuse bleeding complication was dependent on the dose of low molecular weight heparin, particularly in patients without risk factors.

CONCLUSIONS

The use of a narrow definition of thromboembolism lead to a pattern of risk factors which was partly different from that found in previous studies, which were usually based on diagnosis with the 125I-fibrinogen uptake test.

Clinical relevance of the fibrinogen uptake test in patients undergoing elective general abdominal surgery--relation to major thromboembolism and mortality. Fragmin Multicentre Study Group

Postoperative thromboembolic complications were evaluated in 2578 patients undergoing elective abdominal surgery, all receiving prophylaxis with low molecular weight heparin. A positive fibrinogen uptake test (FUT) developed in 217 patients (8.4%), while 37 patients (1.4%) had major thromboembolism (TE, defined as proximal deep vein thrombosis and/or pulmonary embolism, verified with phlebography, pulmonary scintigraphy or autopsy). In only 14% a positive FUT was associated with a major TE event. In 19% of the patients with major TE the FUT was negative. In multiple logistic regression the independent predictors for major TE were partially different from those for positive FUT. Thirty day mortality was 3.0%. There were significant associations between both positive FUT and major TE on one hand and mortality on the other (relative risks 2.4 and 5.8, respectively). FUT is not a good predictor of major TE. Both positive FUT and major TE indicate a significant risk of postoperative death.

Safety of dextran in relation to other colloids--ten years experience with hapten inhibition

OBJECTIVE

The effects of hapten inhibition with dextran 1 (molecular weight: 1,000 D, Promit), which is in use since 1982 for the prevention of severe dextran-induced anaphylactic reactions (DIAR) caused by immune complexes, were studied.

DESIGN

Spontaneous reports to the manufacturer and to the WHO database INTDIS regarding adverse reactions to clinical dextran after preinjection of dextran 1 and to dextran 1 alone were collected from 1983 to 1992. During this period a total of 5.1 million doses of dextran 1 were sold in 15 countries.

INTERVENTIONS

Analysis of pre- and post-reaction titers of dextran-reactive antibodies (DRA) was made in most Scandinavian reports.

RESULTS

The incidence of severe DIAR (grades III-V) to clinical dextran after the prophylactic use of hapten inhibition was approximately 1/200,000 patients receiving dextran 1. In Sweden, where reporting of severe adverse drug reactions is mandatory, the incidence was approximately 1/70,000, indicating a 35-fold reduction. Only 2 fatal reactions were reported, an incidence of 1/2.5 million doses, indicating a 90-fold reduction. Both these occurred in patients with extremely high titers of DRA. Side effects to dextran 1, mostly mild, were reported in approximately 1 case per 100,000 doses. These side effects were not antibody mediated.

CONCLUSIONS

The above findings, together with other recent safety profile data, suggest that dextran with hapten inhibition has possibly become the safest plasma substitute in current clinical practice.

Thromboprophylaxis in emergency surgery

Except for hip fracture surgery, emergency surgery has been only exceptionally studied concerning thromboprophylaxis. There are, however, several reasons to believe the frequency to be fairly high and that the patient group would be in need of prophylaxis. This paper discusses various emergency situations and also gives the design for an ongoing controlled study on the effect of postoperative start of thromboprophylaxis with low molecular weight heparin in emergency abdominal surgery.

Monofilament versus multifilament absorbable sutures for abdominal closure

This study compares monofilament continuous absorbable sutures with multifilament interrupted absorbable sutures for abdominal closure. Before closure of an abdominal incision, 988 patients were randomized to receive either a monofilament polyglyconate (Maxon) or a multifilament polyglactin 910 (Vicryl) suture. At 1 year after operation, 684 patients (69 per cent) were examined for the presence of incisional hernia, sinus and other wound-healing problems; 179 (18 per cent) had died and 125 (13 per cent) did not attend for follow-up. Incisional hernia occurred in 8 per cent of patients receiving monofilament continuous sutures compared with 6 per cent of those having multifilament interrupted closure (P not significant). Wound dehiscence occurred in 1 per cent of both groups. The mean time for suturing was 7.1 min for monofilament continuous and 8.7 min for multifilament interrupted sutures (P < 0.001). It is concluded that closure of an abdominal incision can be effected by a monofilament continuous absorbable suture more quickly than by multifilament interrupted absorbable sutures without an increased risk of wound dehiscence or incisional hernia.

Renal effects of high dose desmopressin and dextran. A study in normal subjects and in patients undergoing total hip replacement

Dextran 70 and the haemostatically active vasopressin analogue desmopressin were administered to four healthy volunteers and to 12 patients undergoing total hip replacement. In volunteers the antidiuretic effect of a single i.v. dose of desmopressin (0.3 microgram/kg bodyweight) caused a mean net urine deficit, compared with controls, of 890 ml/24 h. Both drugs increased estimated blood volume, but only the combination caused an increase still persisting after 24 h (+530 ml). Desmopressin-treated surgical patients had the same urine volumes as controls, without the use of more diuretics or more i.v. fluid administration. Creatinine clearance was significantly increased postoperatively in patients on desmopressin, compared with controls. Thus the long-lasting antidiuretic effect of desmopressin seen in healthy volunteers was absent in surgical patients, possibly because there was a compensatory increase in glomerular filtration rate (creatinine clearance).

Hapten inhibition of dextran anaphylaxis. Nine years of post-marketing surveillance of dextran 1

All spontaneous reports to the manufacturer and to WHO's database INTDIS regarding adverse reactions to clinical dextran after preinjection of dextran 1 and to dextran 1 alone 1983-1991 were collected. During 1983-1991 a total of 4.8 million doses of Promit were sold in fourteen countries. The incidence of severe DIAR (grades III-V) to clinical dextran after the prophylactic use of hapten inhibition was approximately one case per 200,000 doses of dextran 1. In Sweden, where reporting of severe adverse drug reactions is mandatory, the incidence was one case per 70,000. This indicates a 35-fold reduction in the incidence of severe DIAR compared with the use of clinical dextran without dextran 1. Only two fatal reactions were reported; the incidence was therefore one case per 2.4 million doses, indicating a 77-fold reduction. Both these occurred in patients with extremely high titers of DRA. Side effects to dextran 1, mostly mild, were reported in one case per 100,000 doses. These side effects were not antibody mediated. It is concluded that the introduction of hapten inhibition with dextran 1 has greatly reduced the risk for serious side effects to dextran, making dextran one of the safest colloids in use.

Effects of desmopressin on blood loss in hip arthroplasty. Controlled study in 50 patients

50 patients undergoing elective total hip replacement under epidural anesthesia and dextran infusion were given two doses of the vasopressin analogue desmopressin 0.3 micrograms/kg BW or placebo in a double-blinded randomized prospective study. Intraoperative blood loss and drainage loss did not differ significantly between groups, but desmopressin reduced the mean total blood loss (calculated from hemoglobin decrease and blood transfusions) by 310 mL (P less than 0.05).

Effects on coagulation and fibrinolysis of desmopressin in patients undergoing total hip replacement

Twelve patients undergoing total hip replacement, with regional anaesthesia and with dextran infusion for plasma expansion and thromboprophylaxis, were given the vasopressin analogue desmopressin (DDAVP) or placebo in a randomized, double-blind prospective study. In controls (n = 6) we found a prolongation of the bleeding time, low factor VIII (FVIII) and von Willebrand factor (vWF) and a decrease in antithrombin III to levels known to be at risk for venous thrombosis. Desmopressin shortened postoperative bleeding time, gave an early FVIII/vWF complex increase, prevented antithrombin III from falling to critically low values and appeared to activate the fibrinolytic system, both by tPA increase and PAI-1 decrease. Thus in the controls we found changes in both coagulation and fibrinolysis indicating a haemorrhagic diathesis as well as a risk for thromboembolism. Desmopressin induced factor changes that possibly reduce both risks.

Effects of desmopressin and dextran on coagulation and fibrinolysis in healthy volunteers

The effects of desmopressin and dextran on haemostasis and fibrinolysis were studied in four healthy volunteers. Both drugs were compared to placebo, each volunteer being subject to four experiments. Dextran 70 (30 g i.v.) moderately decreased VIII:C and vWF:Ag and slightly increased antithrombin III, also when haemodilution and diurnal variation were considered. Desmopressin (0.3 micrograms/kg BW i.v.), alone as well as in combination with dextran, increased VIII: C, vWF:Ag, protein C and tPA and decreased PAI-1. The combination of desmopressin and dextran stimulated coagulation and fibrinolysis and might be of relevance to surgical blood loss as well as to postoperative thromboembolism.

Thromboprophylactic effect of low molecular weight heparin started in the evening before elective general abdominal surgery: a comparison with low-dose heparin

A prospective randomized double-blind trial was performed comparing conventional low-dose heparin with a LMWH fragment (Kabi 2165, Fragmin) for thromboprophylaxis in elective general abdominal surgical patients. The first dose of the fragment was given in the evening before surgery, and thereafter every evening. There were 1002 analyzable patients, 826 having received correct prophylaxis. Sixty three percent of the patients were operated on for malignant diseases. The frequency of DVT was significantly reduced among patients with correct prophylaxis with the heparin fragment (9.2 to 5.0%, p = 0.02). In patients with malignancies the reduction was from 11.2 to 6.4% (p = 0.06). The frequency of bleeding was 6.7% among the heparin fragment patients and 2.7% among the patients given conventional heparin (p = 0.01). The corresponding frequencies for patients with malignancies were 3.2 and 2.8%, respectively (p = 0.28). All bleedings were minor and of no clinical significance. Local pain at the injection site was reported significantly less often among patients with the fragment. Twenty patients died, 13 with malignant disease, mortality being the same in the two groups. It is concluded that heparin fragment administered in the evening before surgery and then every evening is a practically acceptable alternative to prevent postoperative DVT in patients undergoing elective abdominal surgery, also when the histology shows malignancy. Thus, the advantages of using LMWH compared with conventional low-dose heparin are simplified administration routines, better thromboprophylactic effect, and less local pain at injection sites. A disadvantage is the slight increase in hemorrhagic side effects, all of minor clinical importance and not seen in patients undergoing surgery for malignancy.

Infarction of the small bowel caused by giant cell arteritis. Case report

A case with giant cell arteritis causing infarction of two segments of the small bowel is described in a 43-year-old woman. Subsequent angiography showed stenoses in both subclavian arteries and one common iliac artery, compatible with Takayasu's disease. The difficulties in distinguishing the different types of granulomatous giant cell arteries are discussed.

Does vaccination of splenectomized patients against pneumococci induce dextran-reactive antibodies?

Polyvalent pneumococcal vaccine containing polysaccharides from serotypes known to be cross-reactive with dextran was used for vaccination of 72 patients either shortly before or on the average 6.25 years after splenectomy. The titer of dextran-reactive antibodies was determined by passive hemagglutination before as well as 6 weeks and 6 months after vaccination. Already prior to vaccination the patients had moderately elevated titers of these antibodies and the titer was somewhat reduced during the study period. Small intergroup differences were observed but the titers of patients who had received cytostatic and/or radiation therapy did not appear to react differently to vaccination. It is concluded that this type of vaccine does not induce dextran-reactive antibodies when given to asplenic individuals.

Hapten inhibition and dextran anaphylaxis

Hapten inhibition with dextran 1 has been used in Sweden since 1982 to prevent severe anaphylactic reactions to dextran. This has led to a reduction in the reports of severe reactions to dextran from 22 per 100,000 units of dextran used between 1975 and 1979, to 1.2 per 100,000 units between 1983 and 1985. The number of fatal reactions decreased from 23 to one. More than 600,000 units of dextran were used during each period.

Low molecular weight heparin given the evening before surgery compared with conventional low-dose heparin in prevention of thrombosis

A prospective randomized double-blind trial was performed comparing conventional low-dose heparin with a low molecular weight heparin fragment for thromboprophylaxis in elective general abdominal surgical patients. The first dose of the heparin fragment was given the evening before surgery, and further doses were given thereafter every evening. There were 1002 analysable patients, 826 having received correct prophylaxis. Of these 1002 patients, 64 per cent were operated on for malignant disease. A total of 20 patients died, 10 in each group. The frequency of deep vein thrombosis was significantly reduced among patients with correct prophylaxis with the heparin fragment (9.2-5.0 per cent, P = 0.02) [corrected]. The frequency of bleeding was 6.7 per cent among the heparin fragment patients and 2.7 per cent among the patients given conventional heparin (P = 0.01), but all bleeds were of minor degree and there was no difference in the reoperation rate for bleeding, or in the transfusion requirements. Local pain at the injection site was reported significantly less often among patients given the heparin fragment.

Histopathological lung changes in immune complex mediated anaphylactic shock in humans elicited by dextran

Severe dextran-induced anaphylactic reaction (DIAR) is being recognized as a form of immediate IgG mediated immune complex reaction. Support for this pathogenesis is found in the correlation between the titer of dextran-reactive antibodies of IgG class and the severity of the reaction. Autopsy records were reviewed in 27 certified cases of fatal DIAR. The most frequent macroscopic findings were dilatation of the right side of the heart and acute pulmonary stasis. Autopsy lung specimens were collected from 17 of these patients. In 15 of the 17 lung specimens pulmonary microemboli were found. The microemboli had the appearance of hyaline eosinophilic globules, and the lung vasculature also contained leukocytes, platelets and disintegrated erythrocytes. These findings show similarity to the findings in a monkey model of known IgG mediated anaphylaxis, and give further support to the proposed pathogenesis of severe DIAR.

Hemorrhagic complications resulting in reoperation after peripheral vascular surgery: a fourteen-year experience

Eighty-nine patients who underwent reoperation because of hemorrhagic complications after peripheral arterial surgery were studied and compared with 103 patients without such complications. Elevation of erythrocyte sedimentation rate, serum creatinine values, and blood pressure before anesthesia was found more often in patients with hemorrhage. The frequency of reoperation due to control hemorrhage was 2.8%; femorodistal and carotid reconstructions were complicated by hemorrhage requiring reoperation significantly more often than other types of vascular surgery, 3.2% and 4.2%, respectively. The use of vacuum drains apparently did not contribute to the diagnosis of bleeding requiring reoperation. Amputation was a more frequent outcome in femorodistal reconstructions complicated by hemorrhage than in similar operations without this complication. After reoperations performed within 48 hours of the primary operation, the clinical course mostly was uncomplicated, whereas in reoperations performed later the bleeding usually was associated with infection of the reconstruction, resulting in a higher frequency of amputation. Most of the late hemorrhages occurred in groin incisions.

Metabolic acidosis in dextran-induced anaphylactic reactions

Results of arterial blood gas and acid-base balance analyses were analyzed in 50 patients suffering from dextran-induced anaphylactic reactions. Metabolic acidosis was always present in severe cases, leading to cardiac arrest, and also frequently found in those with less severe reactions with only slightly impaired circulation. Bronchospastic respiratory signs were frequently encountered but acidosis was noted to develop even without these symptoms. The severity of the acidosis was generally underestimated during treatment. Arterial PO2 and PCO2 were not significantly affected during these reactions.

Deep-vein thrombosis after major non-cardiovascular thoracic surgery

The incidence of deep-vein thrombosis (DVT) verified by fibrinogen test was studied in 44 high-risk patients after major non-cardiovascular thoracic surgery. In eight patients (18%) a total of ten DVT appeared within the first postoperative week. Four thrombi were located at or above knee level. More extensive surgery was associated with higher DVT incidence than lesser operations (32% v. 8%). In patients belonging to blood groups B and AB, DVT was more common than in other blood groups. Five of the six unilateral DVT were detected on the same side as the thoracotomy. The findings suggest that DVT incidence after this kind of surgery may be of the same order as after major general surgery, indicating a need for thromboprophylactic measures.

Does dihydroergotamine potentiate the thromboprophylactic effect of dextran 70? A controlled prospective study in general and hip surgery

In a prospective randomized controlled study on postoperative thromboembolism, 259 patients undergoing elective general surgery, emergency general surgery, total hip replacement or hip fracture surgery were given thromboembolic prophylaxis with either a combination of dextran 70 and dihydroergotamine (DHE) or with dextran 70 alone. 500 ml dextran 70 was infused twice on the day of operation, once on postoperative days 1 and 3, and also on day 5 if the patient was still confined to bed. 0.5 mg DHE was given s.c. twice daily starting before operation and continued for 3 or 5 postoperative days. In hip fracture patients prophylaxis was started as soon as the diagnosis was made. 500 ml dextran 70 was given every other day before operation. DHE was given twice daily if so indicated from randomization. The patients were screened for deep-vein thrombosis (DVT) with the 125I-labelled fibrinogen test for 8 days and followed for one month postoperatively. In hip fracture surgery the incidence of DVT was significantly reduced by the combination of dextran 70 and DHE compared to dextran 70 alone (1/32 vs. 11/36, P = 0.003). However, this synergistic effect of DHE could not be detected in the other patient groups. Fatal pulmonary embolism did not occur. No severe side effects attributable to prophylaxis were noted in either group.

Incidences of fatal postoperative pulmonary embolism after prophylaxis with dextran 70 and low-dose heparin: an international multicentre study

A total of 4352 patients were admitted to a prospective' randomised multicentre trial comparing the prophylactic efficacy of dextran 70 and low-dose heparin against fatal pulmonary embolism after elective operations for general, orthopaedic, urological, and gynaecological conditions. Out of 3984 patients correctly admitted, 1993 were allocated to receive dextran 70 and 1991 to receive low-dose heparin. Withdrawal of prophylaxis because of bleeding or technical difficulties occurred more often in the heparin group, but allergic reactions were more common in the dextran group. Of the 75 patients who died within 30 days after operation, 38 had been given dextran and 37 low-dose heparin. Necropsy was performed in 33 and 32 of these cases respectively. In six patients in each group pulmonary embolism was the sole or a contributory cause of death. Of these, five patients in the dextran group and two in the heparin group had received a full course of prophylaxis. There was no statistically significant difference between the two treatment groups in the incidence of fatal pulmonary embolism after a full course of prophylaxis.

Search for disease-related cytotoxicity in mammary tumor patients

Blood lymphocytes from benign and malignant mammary tumor patients ahd healthy blood donors were tested for cytotoxicity against monolayer cell lines, including two which were derived from breast carcinomas. Generally, the T subset was not cytotoxic, and if so this was not restricted to the relevant cell lines. In accordance with previous results 'null' cells were most efficient in the seemingly non-selective cytotoxicity.