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D Arvidsson

Publications and source records attributed to D Arvidsson.

At least 19 recordsLinked to original sources
PubMed2007

Laparoscopic parenchymal division of the liver in a porcine model: comparison of the efficacy and safety of three different techniques.

BACKGROUND: Bleeding is a known and CO2 embolization a suggested risk factor for increased morbidity after laparoscopic liver resection. Devices for laparoscopic liver parenchymal transection must be evaluated for safety in this context. METHOD: Twelve piglets underwent laparoscopic surgery during CO2 pneumoperitoneum, each animal receiving three 6 cm long transections into the liver parenchyma made with ultrasonic dissector, ultrasonic shears and vessel sealing system, respectively. Endpoints were bleeding, operation time and gas embolization. The transections and embolization events, evaluated with transesophageal echocardiography, were video recorded. Bleeding and embolization were also assessed on video tapes and operating time measured. Arterial blood gases were recorded on line. RESULTS: The ultrasonic dissector was least advantageous in terms of bleeding and operation time. Gas embolization was more frequent with the vessel sealing system than with the ultrasonic dissector and ultrasonic shears. During two episodes of gas embolization, pCO2 increased and pO2 and pH decreased. CONCLUSIONS: Use of all three devices is feasible. Bleeding and operation time are greatest with the ultrasonic dissector. Gas embolization occurs during transection, though in most instances it is completely harmless. Laparoscopic liver surgery with these techniques used may pose a risk of gas embolization with clinical implications. Monitoring for such events is probably to be recommended.

Analysis of Variance↗
PubMed2006

The effects of experimental venous carbon dioxide embolization on hemodynamic and respiratory variables.

BACKGROUND: Laparoscopic liver resection is a relatively new surgical procedure. Carbon dioxide (CO2) pneumoperitoneum and laparoscopic liver dissection are recognized as risk factors for CO2 embolism to the pulmonary circulation. The embolization can be difficult to detect and can theoretically increase peri-operative morbidity. The aim of this study was to evaluate the cardiopulmonary effects in a pig model during a time period of 4 h after an experimental CO2 embolization. METHODS: Eleven piglets were anesthesized. Nine were embolized with a single intravenous injection of 0.4 ml/kg CO2 and two served as controls. Respiratory and cardiovascular variables, including pulmonary artery pressure and cardiac output, were monitored for 4 h after embolization, and arterial blood gases were monitored on-line. RESULTS: The embolized piglets had an increase in ventilatory dead space, pulmonary vascular resistance and pulmonary artery pressure and a decrease in cardiac output that lasted throughout the 4-h observation time. The mean arterial pressure and heart rate were unchanged. An early sign of embolization was a rapid fall in end-tidal CO2 and P(a)O2 and a rise in P(a)CO2. CONCLUSION: Negative changes in cardiopulmonary physiology persisted for at least 4 h after a single intravenous CO2 injection, in spite of this gas being highly soluble in blood. This is a more prolonged influence of CO2 embolization than previously described. Extensive monitoring for early detection of an embolization may be recommended to limit morbidity in patients undergoing laparoscopic liver surgery.

Animals↗
PubMed2005

Radiofrequency ablation in the liver close to the bile ducts: can intraductal cooling offer protection?

BACKGROUND: One complication of radiofrequency ablation (RFA) of the liver is biliary duct damage. Intraductal cooling (IDC) has been proposed as a means of protection. METHODS: In the first experiment, designed to evaluate the influence of IDC on the RFA procedure per se and on lesion formation, lesions were created in vivo in pig liver with and without IDC. The RFA needle was placed with a 1.5-cm safety margin from the bile ducts. In the second experiment, designed to evaluate the potential protective effects of IDC, lesions were created close to a bile duct with and without IDC. RESULTS: With the safety margin, the RFA parameters and lesion size were not negatively affected by IDC. Microscopic examination revealed that IDC had a protective effect in most of the lesions created close to a bile duct. CONCLUSIONS: The IDC procedure was feasible and had no negative effect on the RFA procedure or the lesions. However, the protective effect of IDC was not statistically significant (p = 0.12).

Animals↗
PubMed2005

Randomized clinical trial comparing 5-year recurrence rate after laparoscopic versus Shouldice repair of primary inguinal hernia.

BACKGROUND: The Shouldice technique is the 'gold standard' of open non-mesh hernia repair. The aim of this study was to compare 5-year recurrence rates after Shouldice and laparoscopic transabdominal preperitoneal patch (TAPP) repair for primary inguinal hernia. METHOD: Men with a primary unilateral inguinal hernia were randomized to either Shouldice or TAPP operation. An independent observer scored the surgeons' performance. Follow-up comprised clinical examination after 1 year, a questionnaire after 2 and 3 years, and a clinical examination after 5 years. RESULTS: Between February 1993 and March 1996, 1183 patients were included. Nine hundred and twenty patients were followed for 5 years, 454 in the TAPP group and 466 in the Shouldice group. Recurrences were evenly distributed between groups throughout the follow-up period. The cumulative recurrence rate after 5 years was 6.6 per cent in the TAPP group and 6.7 per cent in the Shouldice group. Postoperative pain was a risk factor for recurrence after Shouldice operation but not after TAPP repair. There was a correlation between a low surgeon's performance score and recurrence. CONCLUSION: The 5-year recurrence rate is acceptable, with no difference between TAPP and Shouldice repair. Poor operative performance resulted in a higher recurrence rate. The TAPP operation represents an excellent alternative for primary inguinal hernia repair.

Adult↗
PubMed2005

Physical activity questionnaire for adolescents validated against doubly labelled water.

OBJECTIVE: To validate a physical activity questionnaire for adolescents (PAQA) adapted from the International Physical Activity Questionnaire (IPAQ). DESIGN: Energy expenditure was measured during a 14-day period with doubly labelled water (DLW). PAQA was administered as an interview at the end of the period, asking for physical activity in school, during transportation and leisure-time, during a habitual week. Energy expenditure (EE(PAQA)) was calculated as the product of total physical activity + sleep and predicted resting metabolic rate, and was compared to energy expenditure from DLW (EE(DLW)), thermic effect of feeding excluded. SETTING: Participants were recruited from grade 9 in a compulsory school in Göteborg, Sweden. All data were collected at school, and distribution of DLW and measuring of resting metabolic rate were performed at Sahlgrenska University Hospital. SUBJECTS: A total of 33 adolescents (16 girls, 17 boys) 15.7 (0.4) y performed all measurements. RESULTS: : For the whole group, PAQA underestimated energy expenditure by 3.8 (1.7) MJ (P<0.001). There was a strong correlation (r = 0.62, P<0.001) between EE(PAQA) and EE(DLW), but not for boys (r = 0.42, P = 0.090) and girls (r = 0.33, P = 0.22) separately. CONCLUSIONS: PAQA is not able to predict energy expenditure in Swedish adolescents, largely explained by the amount of unreported time. The ability to rank adolescents energy expenditure is questioned because of the gender effect, although we found a strong correlation for the whole group.

Adolescent↗
PubMed2005

Virtual reality colonoscopy simulation: a compulsory practice for the future colonoscopist?

BACKGROUND AND STUDY AIM: As for any manual procedure, the learning curves for medical interventions can have undesirable phases, occurring mostly in the early experience of applying a technique. There have been impressive advances in endoscopic procedures during recent years, and there is an emerging trend that the number of procedures is increasing in parallel with these. In addition, the introduction of screening programs for colorectal cancer will also increase the numbers of procedures needed. Recent developments in medical simulation seem promising with regard to the possibility of "training out" undesirable parts of the learning curve outside the operating room. The aim of this study was to investigate whether the use of the AccuTouch flexible endoscopy simulator improves the early part of the learning curve in colonoscopy training. METHOD: 12 endoscopy trainees, 10 surgeons and two medical gastroenterologists, all with experience in gastroscopy but with no specific colonoscopy experience, were randomly assigned to either simulator training or to a control group. They all received the same theoretical study package and the training group practiced with the AccuTouch colonoscopy simulator until a predefined expert level of performance was reached. All trainees performed their first ten individual colonoscopies described in detail in a separate protocol. RESULTS: Trainees in the simulator-trained group performed significantly better (P=0.0011) and managed to reach the cecum in 52% of their cases (vs. 19% in the control group), and were 4.53 times more likely to succeed compared with the controls. Additionally, there was a significantly shorter procedure time and less patient discomfort in the hands of the simulator-trained group. CONCLUSION: Skills acquired using the AccuTouch simulator transfer well into the clinical colonoscopy environment. The results of this trial clearly support the plan to integrate simulator training into endoscopic education curricula.

Adult↗
PubMed2005

Liver operations in Sweden in 1987-99.

BACKGROUND AND AIMS: Liver surgery is developing with new techniques and treatment modalities. The aim of this study is to describe liver surgery over a long period of time in a country with a public health care system. PATIENTS AND METHOD: A register study including adult patients admitted for liver resection in Sweden (population 8.8 million) selected from the Inpatient Register 1987-99. Additional data were collected from the Swedish Cancer Register and the Cause of Death Register. Analyses of the patients, indications, mortality and causes of death are presented. RESULTS: 2,405 operations were performed (21 per million per year). The most frequent indication was colorectal metastases (27%). The 5-year survival after an operation for primary liver cancer and colorectal liver metastases was 27% and 26%, respectively. CONCLUSIONS: Few patients were admitted for liver operations compared to expected figures. The survival rates are in conformity with those previously published. With an increasing awareness of the relatively favourable prognosis and the introduction of new methods, the volume of liver operations will probably increase in Sweden.

Adolescent↗
PubMed2003

Long-term results from laparoscopic common bile duct exploration.

BACKGROUND: The aim of this study was to evaluate the long-term results after laparoscopic common bile duct exploration (LCBDE). METHODS: A retrospective review of 175 consecutive patients who underwent attempted LCBDE between 1992 and 1999 was conducted. Laparoscopic transcystic exploration was accomplished in 110 patients and laparoscopic choledochotomy in 52 patients. Conversion to an open common bile duct exploration was required for 13 patients (7.4%). Retained common bile duct stones occurred in eight patients (4.6%). The 30-day postoperative morbidity was 6.9%, and there was no 30-day mortality. All the patients (alive and localized) received a questionnaire evaluating long-term results. RESULTS: Of the 175 patients, 169 (4 unrelated deaths and 2 patients lost to follow-up evaluation) received and 152 (90%) returned the questionnaire. The follow-up period ranged from 6 to 72 months (median, 36 months). One patient developed recurrent common bile duct stones. There were no signs or evidence of common bile duct stricture in any patient. CONCLUSION: The LCBDE procedure can be performed without increased risk of late bile duct complications.

Abscess↗
PubMed2003

Energy intake in Swedish adolescents: validation of diet history with doubly labelled water.

OBJECTIVE: To compare habitual energy intake (EI) estimated from diet history (DH) with total energy expenditure (TEE) measured with doubly labelled water (DLW) in adolescents. DESIGN: DH included a detailed questionnaire and an interview. TEE was measured during a 14-day period. Adequate (AR), under- (UR) and over-reporters (OR) were defined from the ratio EI/TEE: AR 0.84-1.16, UR <0.84 and OR >1.16. SETTING: Participants were recruited from grade 9 in a compulsory school in Göteborg, Sweden. All data were collected at school and DLW dosages were distributed at Sahlgrenska University Hospital. SUBJECTS: A total of 35 adolescents (18 boys, 17 girls), 15.7 (0.4) y. RESULTS: EI was 11.0 (3.6) MJ and TEE was 11.4 (2.1) MJ (P=0.42). DH was able to rank EI compared to TEE (Spearman's r=0.59, P< or =0.001). For girls, EI was 18% lower (P=0.0067) and for boys, EI was 7% higher (P=0.26) compared to TEE. The 95% limits of agreement for difference between TEE and EI were -5.6 to 6.5 MJ. In total, 20 subjects were defined as AR (57%), nine as UR (26%) and six as OR (17%). Energy from in-between meals was 33% lower (P=0.0043) in UR girls and 57% higher (P=0.026) in OR boys, compared to adequate reporting girls and boys, respectively. In UR girls, energy-adjusted intake (10 MJ) of specific foods did not differ significantly, fat was lower and carbohydrate and vitamin C were higher compared to AR girls (all P<0.05). OR boys had no significant differences in food and nutrient intake in 10 MJ compared to AR boys. CONCLUSION: The diet history was able to capture EI for the group and to rank subjects. There was a wide individual range in reporting-accuracy related to gender. SPONSORSHIP: The Ingabritt and Arne Lundberg Foundation, The Wilhelm and Martina Lundgren Foundation.

Adolescent↗
PubMed2002

Postoperative convalescence after inguinal hernia surgery: prospective randomized multicenter study of laparoscopic versus shouldice inguinal hernia repair in 1042 patients.

Interest in inguinal hernia surgery has increased significantly with the introduction of new operating techniques during the past decade. This multicenter study compared short-term results in patients treated by the laparoscopic transabdominal preperitoneal patch technique (TAPP; n = 518) and the Shouldice technique (n = 524). We evaluated demographics, operative data, complications, hospital stay, postoperative pain, use of cs, functional status, sick leave, and complaints up to 3 months postoperatively. The median operating time was shorter in the Shouldice group (55 vs. 65 min), but there were no significant differences in complication rates, and major complications were rare. The hospital stay was 1 day or less in over 98% of cases in both groups, but more operations were performed on outpatient basis in the Shouldice group. In the TAPP group postoperative pain and analgesic consumption were less, postoperative functional status was better, and sick leave was shorter (10 vs. 14 days). These results show that the two methods are equally safe and have few major complications. The TAPP operation is associated with less postoperative pain, better postoperative functional status, and shorter sick leave, but at the price of a longer operating time.

Aged↗
PubMed2001

Does training in a virtual reality simulator improve surgical performance?

BACKGROUND: The development of computerized surgical simulators in a virtual reality environment demands models for proper validation. Recent investigations have shown that a virtual reality simulator (MIST-VR) is a reliable tool for the assessment of laparoscopic psychomotor skills and that it improves the automation of the so-called fulcrum effect. Therefore, we set out to determine whether training with the MIST-VR would improve the surgical performance of surgically inexperienced medical students and to see if results obtained in the simulator would correlate with surgical performance. METHODS: A total of 29 medical students were randomized into two groups. One group received preoperative MIST-VR training. Both groups then performed a simulated laparoscopic appendectomy in a pig. The operations were videotaped and examined by three independent observers. RESULTS: There was no significant difference in performance between the two groups. The performance with the MIST-VR correlated with the results in surgery. CONCLUSION: A method that can measure surgical skill, based on the scoring of independent observers who view videotaped performances, seems to be reliable. MIST-VR did not improve the surgical skills of the subjects, but the results with MIST-VR did predict surgical outcome.

Clinical Competence↗
PubMed2001

Optimal positive end-expiratory pressure (PEEP) settings in differential lung ventilation during simultaneous unilateral pneumothorax and laparoscopy: an experimental study in pigs.

BACKGROUND: A combined thoraco-laparoscopic technique for esophageal resection is technically possible, but it requires special attention to ventilation. The positive insufflation pressure normally used in laparoscopy will, when communication between thorax and abdomen is established, create a pneumothorax. METHODS: We performed an experimental study of differential lung ventilation with different levels of positive end-expiratory pressure (PEEP) settings during thoraco-laparoscopy in anesthetized pigs. RESULTS: Positive pressure insufflation of carbon dioxide (CO2) resulted in elevated pulmonary capillary wedge pressure, hypercarbia, and respiratory acidosis. Hypoxemia, however, developed only at lower settings of PEEP. Heart rate, mean arterial pressure, and cardiac output remained relatively stable. CONCLUSION: Pneumopleuroperitoneum under positive CO2 insufflation pressure had adverse effects on blood gases. Hypercarbia, respiratory acidosis, and hypoxemia were early manifestations that occurred even in the presence of hemodynamic stability. The application of PEEP equal to or above CO2 insufflation pressure improved blood gases; in particular, the hypoxia could be avoided. No beneficial effects of differential lung ventilation were documented.

Animals↗
PubMed2000

HandPort-assisted laparoscopic splenectomy in massive splenomegaly.

BACKGROUND: Laparoscopic splenectomy of normal-sized spleens is performed with increasing frequency. By using a handPort, which allows the intraperitoneal introduction of one surgeon's hand, massively enlarged spleens may also be extirpated via a laparoscopy-assisted technique. METHODS: Seven patients (54-80 years) with massive splenomegaly (3.5-5.8 kg) underwent handPort-assisted laparoscopic splenectomy. All patients had spleens that extended beyond the umbilicus, hypersplenism, and discomfort in the upper left quadrant due to intractable hematological malignancy. RESULTS: Both the operation and recovery were uneventful in five of the patients, but one patient had to be converted to an open procedure due to splenic damage and bleeding, and another was reoperated for hemorrhage from a trocar. The handPort allowed splenic protection while the trocars were introduced and instruments changed. It also enabled splenic mobilization, particularly prior to stapling of the hilar structures and dissection of the upper splenic pole. CONCLUSIONS: HandPort-assisted laparoscopic splenectomy seems to be a viable alternative for massive splenomegaly, but it requires further evaluation with respect to safety, efficacy, and indication.

Aged↗
PubMed2000

Antireflux surgery in Sweden, 1987-1997: a decade of change.

BACKGROUND: The aim of this study was to analyse whether new therapeutic options--the introduction of proton-pump inhibitors (PPI) in 1989 and the laparoscopic technique in 1992--altered the surgical treatment of gastro-oesophageal reflux disease (GORD) in Sweden. METHODS: Data obtained from the Centre for Epidemiology (EpC) on patients undergoing surgery for GORD from 1987 to 1997 was analysed, and the information was validated with a questionnaire to all surgical departments. RESULTS: The questionnaire gave a response rate of 94%, and the figures corresponded well with those obtained from the EpC. In 1987, 456 antireflux procedures were performed. Ten years later this figure had increased to 1303. This approximately threefold increase started before the introduction of PPI and was even more pronounced during the following few years. The development of laparoscopic antireflux surgery did not alter this increase. In 1997, 76% of the procedures were performed laparoscopically. The fundoplication rate rose from 5.5 to 12.7 procedures/100,000 inhabitants. The rates varied greatly among different counties; 7 of 23 still had a fundoplication rate of less than 10 in 1997. The median number of procedures per hospital in 1997 was 10. Only two departments accomplished more than 50 antireflux procedures. CONCLUSION: Within 5 years the laparoscopic technique replaced the open procedure as the method of choice. However, the increase in the frequency of antireflux surgery was apparent even before the introduction of laparoscopy.

Adult↗
PubMed2000

Hand-assisted laparoscopic surgery (HALS) with the HandPort system: initial experience with 68 patients.

OBJECTIVE: To evaluate the feasibility and potential benefits of hand-assisted laparoscopic surgery with the HandPort System, a new device. SUMMARY BACKGROUND DATA: In hand-assisted laparoscopic surgery, the surgeon inserts a hand into the abdomen while pneumoperitoneum is maintained. The hand assists laparoscopic instruments and is helpful in complex laparoscopic cases. METHODS: A prospective nonrandomized study was initiated with the participation of 10 laparoscopic surgical centers. Surgeons were free to test the device in any situation where they expected a potential advantage over conventional laparoscopy. RESULTS: Sixty-eight patients were entered in the study. Operations included colorectal procedures (sigmoidectomy, right colectomy, resection rectopexy), splenectomy for splenomegaly, living-related donor nephrectomy, gastric banding for morbid obesity, partial gastrectomy, and various other procedures. Mean incision size for the HandPort was 7.4 cm. Most surgeons (78%) preferred to insert their nondominant hand into the abdomen. Pneumoperitoneum was generally maintained at 14 mmHg, and only one patient required conversion to open surgery as a result of an unmanageable air leak. Hand fatigue during surgery was noted in 20.6%. CONCLUSIONS: The hand-assisted technique appeared to be useful in minimally invasive colorectal surgery, splenectomy for splenomegaly, living-related donor nephrectomy, and procedures considered too complex for a laparoscopic approach. This approach provides excellent means to explore, to retract safely, and to apply immediate hemostasis when needed. Although the data presented here reflect the authors' initial experience, they compare favorably with series of similar procedures performed purely laparoscopically.

Abdomen↗
PubMed1999

[Laparoscopic living-donor nephrectomy. A small study shows positive results, but the procedure still lacks satisfactory evaluation].

Retrospective analysis and comparison of a small series of 12 laparoscopic live donor nephrectomy (LapLDN) procedures with 15 open live donor nephrectomies, all 27 performed in 1998, showed operating time to be significantly longer but sick leave shorter and hospital stay somewhat shorter in the LapLDN subgroup. One patient in the open procedure subgroup developed herniation and scar discomfort, and in one LapLDN procedure severe bleeding necessitated conversion to open nephrectomy. All kidneys in both subgroups manifested immediate resumption of function after transplantation. Though the LapLDN procedure has yet to be satisfactorily evaluated, the present findings were predominantly in its favour.

Evaluation Studies as Topic↗