Search PubMed⌕ Search

Biomedical subjects

S Winnock

Publications and source records attributed to S Winnock.

At least 37 records · Page 2Linked to original sources

[Hemodynamic changes during celioscopy: a study carried out using thoracic electric bioimpedance].

In 18 women A.S.A. physical status 1, a noninvasive thoracic electrical bioimpedance method was used to evaluate haemodynamic changes during gynaecological laparoscopy. A significant decrease in cardiac index was observed after peritoneal insufflation, from 3.2 to 2.8 L.min-1.m-2 and returned to the initial values after ten minutes of Trendelenburg's position. Elevated intra-abdominal pressure was also associated with a significant increase in mean arterial pressure (from 68 to 88 mmHg) and systemic vascular resistance index (from 1620 to 2491 dyn.s.cm-5.m-2). However, values were not restored after peritoneal exsufflation: systemic vascular resistance index values remained 30 per cent higher than that before insufflation. Decreased venous return may account for the significant decrease in cardiac output but mechanical compression does not explain the persistent elevation of systemic vascular resistance.

Adult↗

[Dobutamine during anesthesia of patients at risk for heart failure. A controlled prospective multicenter study of 93 surgical patients over 64 years of age].

Most anaesthetic agents cause cardiac depression possibly hazardous in the elderly, especially in presence of a poor cardiac reserve. Ninety-three patients undergoing non cardiac surgery lasting more than 90 min. were entered in a double-blind multicentre randomized trial. They were 65 year old or more and unaffected by evolutive angina pectoris. After insertion of a Swan Ganz catheter and an arterial cannula, anaesthesia was induced by thiopentone, fentanyl and 02/nitrous oxide (50%). Forty-five patients were infused dobutamine 7 micrograms.kg-1.min-1 (group D) from 10 min. after induction till the completion of surgery. Forty-eight patients received a placebo (group P). Haemodynamic parameters were recorded throughout anaesthesia and at its emergence. After induction, heart rate, pulmonary capillary wedge pressure and mean pulmonary artery pressure did not change significantly; mean arterial pressure, cardiac index, stroke index and left ventricular stroke work index decreased by 21, 33, 28 and 42% respectively (p less than 0.001); systemic and pulmonary arterial resistances increased by 12 and 37% respectively (p less than 0.001). In group P, these changes persisted throughout the procedure but, 30 min after extubation, cardiac index returned to control levels due to a 25% increase in heart rate; in this group 4 patients presented with both perioperative low cardiac output and persistent postoperative confusion. With dobutamine, haemodynamic parameters returned to preoperative values and heart rate increased by 12 b.min-1. More arrhythmias and hypertensive episodes but less hypotensions occurred in group D. Substantial haemodynamic changes occur during anaesthesia and surgery in elderly patients. Dobutamine corrects the peroperative decrease in cardiac output and blood pressure, and might prevent postoperative neurological disorders.

Aged↗

[Peroperative angiography in reparative surgery of the lower limbs. Apropos of experience with 1099 cases].

The authors report their experience of per-operatory angiography in a series of 1,099 cases over 13 consecutive years. The main interest is the limitation in the rate of early reintervention, which frequently causes morbidity and mortality in this type or surgery. The serial nature of the technique is emphasized, and is most comparable to pre-operatory exploration. The various technical details are specified. Some hemodynamic troubles noted during injection (aortography) contraindicate the method in high-risk subjects. The main indications are, above all, control of restorative acts, but also a per-operatory diagnosis of a lesion, and the assessment of blood stream at a lower level. The results are morphological and the various anomalies discovered are reviewed, with iconography, in relation to each type of surgical act (disobliteration, bypass). In situ bypasses are considered separately. The data are also hemodynamic, and justify the six successive X-ray film technique. Deblocking (embolectomy with a balloon catheter) and endarterectomies were found to give more technical imperfections than bypasses. The rate of extemporaneous corrections tripled during the second period (1978 to 1986), and this was no doubt due to an extension in operative indications (19% versus 6% at the beginning). Dacron bypasses (fibrinous debris) and in situ bypasses (detection of anatomical abnormalities, location of shunts) were more often incriminated in immediate reinterventions than Dardik homografts or PTFE.

Angiography↗

[Hemodynamic changes caused by laparotomy during aorto-iliac surgery].

A haemodynamic study was carried out on 53 patients undergoing elective surgery of the abdominal aorta in order to assess the haemodynamic changes consequent to abdominal manipulations prior to aortic clamping. Surgery was carried out under general anaesthesia and ventilation was controlled. The following parameters were monitored: mean arterial pressure (Pa), cardiac index (CI), systolic index (SI), systemic vascular resistances (Rsa), pulmonary vascular resistances (Rpa), heart rate (fC). Cutaneous circulation was monitored using a photoplethysmographic transducer. The following haemodynamic pattern was seen as the peritoneal cavity was opened and traction on the mesentery was applied: CI +40.7%; fC +28.61%; SI +9.85%; Rsa -39.16%; Rpa -28.43%; Pa -15.7%. The recording of the facial cutaneous photoplethysmographic wave showed an increase of 50%. In some extreme cases, a state of cardiovascular collapse with marked cutaneous erythema strongly resembling anaphylactic shock ensued. The physiopathology of these cardiovascular reactions is unclear, but the haemodynamic pattern as well as the cutaneous vasodilation suggest a stimulation of both vagal and sympathetic nervous systems and the release of vasoactive substances into the general circulation.

Adult↗

Treatment of deep venous thrombosis with a very low molecular weight heparin fragment (CY 222).

Thirty patients presenting with phlebographically confirmed deep venous thrombosis were treated with a very low molecular weight heparin fragment (CY 222) in an open and prospective phase-2 trial. A uniform dosage of 750 IC anti-factor Xa units/kg/day was administered subcutaneously for 10 days or more to patients whose thromboses were categorized as postsurgical (17 cases) or medical (13 cases). The clinical symptoms of venous thrombosis diminished in 93% of the patients overall. The extent of vascular clearing was assessed by an original scoring system which compared the pre- and posttreatment phlebographies. The effect of treatment was globally rated 'very good' (more than 75% lysis) in 37% of the patients, 'good' (about 50% lysis) in 40% and 'poor' (0-25% lysis) in 17%; the phlebographic thrombosis worsened in 6.6%. Little change occurred in laboratory tests exploring thrombolysis, but a strong anti-factor Xa activity was detected.

Adolescent↗

[CY 222, a very low molecular weight heparin, in the curative treatment of deep venous thrombosis. Apropos of 95 cases. Clinical and phlebographic results].

Efficacy of a very low molecular weight heparin, CY 222, in the treatment of deep venous thrombosis of lower limbs was evaluated in a prospective clinical trial instituted in November 1984. CY 222 was administered as subcutaneous injections of 0.03 ml.kg-1 daily (750 anti-Xa U.kg-1.d-1) as 3 divided doses over a minimum of 10 days. Efficacy was rated as a function of clinical and phlebographic criteria. The group of 95 patients treated was a heterogenious one: 38% medical, 62% surgical, and 48% of the total group had partial interruption of vena cava previous to study. The period between first clinical manifestations of the deep thrombosis and therapy varied between one day and 3 months (mean: 1 1/2 days). Clinical symptomatology significantly and globally regressed in 88% of the patients. Comparisons between phlebographic findings at start and end of treatment are expressed using Arnesen's score (cf. table).

Drug Evaluation↗

[Duodenopancreatic injuries. Diagnostic and therapeutic considerations apropos of 25 cases].

A review of a homogeneous series of 25 cases of duodenopancreatic injuries emphasizes the serious nature of the lesions operated upon at the acute pancreatitis stage. An early diagnosis of these duodenopancreatic lesions is essential since they are often included in the context of multiple injuries. Principal diagnostic difficulties arise in lesions due to contusion without associated intra-abdominal injuries. In these cases ultrasound and CT scan imaging provide valuable data, particularly the latter exploration which is 89% reliable in demonstrating pancreatic morphology. Treatment differs as a function of presence of isolated or combined duodenal and pancreatic lesions and of lesional type. It should be as conservative as possible, although exeresis for lesions of body and tail of pancreas is currently performed more frequently.

Adolescent↗

[Diagnostic and therapeutic angiography in severe retro- and subperitoneal hematomas].

This study of the value of arterial angiography was carried out in 22 patients with serious retroperitoneal hemorrhage. In the first instance, this investigation determines the number of hemorrhages, their sites and flows. Later on it can be used to evaluate the volume of the hemorrhage and its effect on vascularisation of the abdominal viscera so that an initial prognosis can be made. At a later stage it also provider valuable date when setting up an appropriate selective embolisation based on the number of sites involved.

Abdominal Injuries↗

[Peroperative autotransfusion].

Between April 1976 and December 1984, 297 patients underwent major elective and emergency surgery using intraoperative autotransfusion (Bentley ATS unit). An amount of 732 l of blood was reinfused, representing 61% of the total intraoperative blood transfusion. Thanks to this method, an average 2.46 l of blood per patient was spared, with a range of 0.9 to 6 l according to the type of surgery (elective or emergency). Twelve accidents are reported, including four bradycardias (less than 45 b X min-1), two air emboli and six haemorrhages due to an excess of anticoagulation. These complications were related either to poor technique (too great a transfusion output) or insufficient blood anticoagulation control. Simplicity of use and high transfusion output of the device adapted to the blood loss are the advantages of intraoperative autotransfusion.

Adult↗

[Pleural clot ablation and fibrinolytic agents].

Two patients presenting with an important intrapleural clot with cardiorespiratory repercussions were given in situ thrombolytic treatment after drainage with a suction tube had failed. The first patient was treated immediately after thoracophrenolaparotomy for hepatic surgery. Dissolution of the clot was obtained with two local injections of urokinase (450,000 IU). The second patient was treated on the tenth day of a recurring post-traumatic clot, with urokinase (75,000 IU, then 225,000 IU) each day. In addition, this patient received lys-plasminogen locally (15 mukat, then 30 mukat). Dissolution of the clot was complete within five days. Clinical tolerance was excellent and there was no effect on the usual clotting studies. This study confirms previous findings, and underlines the usefulness of this method and its lack of adverse effects, even immediately postoperatively.

Adult↗

[Paradoxical systemic emboli. 5 case reports].

Paradoxical systemic embolism by venous emboli in the arterial circulation can be explained by a right-left shunt. In 5 patients, the diagnosis of paradoxical emboli was definite in three cases, and suspected in two others. Venous, arterial and cardiac angiography define the anatomical criteria which alone can confirm the diagnosis. The introduction of a caval filter can prevent recurrent emboli which has a serious prognosis.

Angiography↗

[Anatomo-clinical correlations after the treatment of iliocaval phlebitis with a 1-year follow-up].

Clinical results and anatomical findings on isotopic angiography, after a minimum follow-up period of one year, were compared in 32 patients treated for iliocaval venous thrombosis. Therapy had involved: iliofemoral thrombectomy alone (8 cases), iliocaval thrombectomy and retroperitoneal clip (10 cases), a clip alone (5 cases), fibrinolysis and heparin therapy (3 cases), heparin therapy alone (6 cases). Overall clinical results were considered as being good in 26 patients and poor in 6, whereas permeability of the main venous axis was confirmed by isotopic phlebography in only 5 cases. There appears to be a total lack of parallelism between clinical results and anatomical findings following treatment of these recent iliocaval phlebitis cases.

Adult↗