bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitric oxide synthase-independent pathway(s) of nitric oxide formation after intestinal ischaemia–reperfusion
Authors: Bahrami S , Sobhian B , Kozlov A , Duvigneau C , Nohl H , Jafarmadar M , Redl H 
Published: March 2003

Abstract

Background
Recent evidence suggests that nitric oxide produced in the gastrointestinal tract, in concert with other vasoactive mediators, plays an essential role in the regulation of splanchnic circulation.

Methods
To determine the sites and pathways of nitric oxide formation, electron paramagnetic resonance spectroscopy and the nitric oxide trap diethyldithiocarbamate-Fe were used to detect directly nitric oxide formed in intestine, liver and lungs of rats subjected to local intestinal ischaemia–reperfusion (I/R), in the presence or absence of nitric oxide donors or inhibitors. In addition, the role of nitric oxide in control of the gastrointestinal circulation was determined by means of a coloured microsphere technique employing N-(G)-Monomethyl-L-arginine (L-NMMA) in rats subjected to haemorrhagic shock followed by resuscitation.

Results
In contrast to remote organs lung and liver (no change), intestinal I/R resulted in an increase in nitric oxide formation in intestinal tissues. Administration of the non-specific nitric oxide inhibitor L-NMMA caused a decrease in I/R-independent basal nitric oxide levels in lung and liver but did not influence the I/R-induced increase in nitric oxide formation in intestinal tissues. In support of this, reverse transcriptase–polymerase chain reaction analyses showed inducible nitric oxide synthase (NOS) expression in the lung but not in intestinal tissues. In the microsphere experiment, a moderate and therapeutic dose of L-NMMA administered after the completion of resuscitation, which improved haemodynamic conditions and outcome, did not alter the intestinal circulation.

Conclusion
The data suggest that the early-phase I/R-induced nitric oxide formation in ischaemic intestinal tissue is probably NOS independent, while nitric oxide formation in normoxic remote tissues is partially NOS dependent. In addition, the authors' nitric oxide-related therapeutic approaches reveal that only the regulation of nitric oxide (e.g. nitric oxide supplementation during resuscitation or reperfusion and/or nitric oxide inhibition or modulation after resuscitation) may protect against hypovolaemic insults.
Surveillance of infections acquired in intensive care units in the Netherlands
Authors: Mintjes-de Groot A J , Geubbels E L P E , van den Berg J M J , de Boer A S 
Published: March 2003

Abstract

Background
The aim was to develop and implement standardized surveillance of infections acquired in the intensive care unit (ICU) in the PREZIES network of hospitals in the Netherlands.

Methods
Surveillance was standardized by protocol and uniform software. Patients were included if they stayed in the ICU for 48 h or more. Data were aggregated at the national level and analysed univariately.

Results
Standardized surveillance of infections acquired in the ICU was introduced in 22 (5 per cent) of hospitals in the Netherlands. Data on 990 patients from ten hospitals (July 1997 to September 1998) were available for analysis. Median length of stay was 6 days. The median Acute Physiology and Chronic Health Evaluation score was 18 and the median age 64 years. In total 256 patients became infected. Per 1000 patient days, 16·1 pneumonias, 3·7 cases of central vascular catheter-related sepsis and 11·1 urinary tract infections were found. Per 1000 patient days, patients were ventilated for 708 days, had a urinary catheter for 950 days and a central vascular catheter for 746 days. Selective contamination of the gastrointestinal tract was employed in 6 per cent and systemic antibiotics in 68 per cent of patients.

Conclusion
It is possible to conduct standardized surveillance of ICU-acquired infections. The data provide insight into the incidence of nosocomial infections in ICU patients in the Netherlands and can be used as reference values for participating hospitals.
Dutch reference data on the incidence of surgical site infection
Authors: Geubbels E , Mintjes J , van den Berg J M , de Boer A 
Published: March 2003

Abstract

Background
The PREZIES national surveillance network supports Dutch hospitals in introducing surveillance of surgical site infection (SSI), generates reference data on the incidence of SSI and associated risk factors, and provides an infrastructure for interventional research. Its ultimate goal is to reduce the occurrence of SSI. The aim was to discuss the methods and results of the national SSI surveillance.

Methods
The participating institutions developed a surveillance protocol and an agreement on participation and privacy aspects. For each patient under surveillance, infection control practitioners collected data on the type of procedure, the occurrence of a superficial and/or deep SSI, and on several risk factors, i.e. age, American Society of Anesthesiologists score, wound contamination class, duration of surgery, preoperative length of stay, use of antibiotic prophylaxis, multiple surgery and elective/emergency surgery. Hospitals received standardized feedback reports comparing their own SSI rates with the national reference. Validation and use of surveillance data were studied within subsets of hospitals.

Results
Since June 1996, 70 of 114 hospitals of all types and sizes participated. The Table shows the number of operations, the incidence of all SSIs, the use of prophylactic antibiotics and the number of participating hospitals for five commonly recorded procedures.
Of 38 hospitals studied, 19 used surveillance results in education, 22 in policy and decision making, and 16 in initiating interventions. Five reported a reduction in SSI incidence. A prevalence survey of SSI showed high agreement (κ = 0·88) with the validating team.

Conclusion
The PREZIES network provides hospitals with good quality national reference data that are used to support their policy for prevention of SSI.
New approach in flow-cytometric determination of endotoxin during endotoxic shock
Authors: Staubach K-H , Nolde J , Brade H , Woltmann A , Bruch H-P 
Published: March 2003

Abstract

Background
Serum endotoxin was formerly measured with the non-specific Limulus lysate assay. The present approach was to quantitate the amount of endotoxin bound by peripheral mononuclear cells in order to develop a method for the diagnosis of early septic shock.

Methods
Using a murine monoclonal antibody (WN1-222/5), which binds highly specifically to lipopolysaccharide (LPS), a new method for measuring the amount of LPS bound to peripheral mononuclear cells was developed. Ten pigs were studied under sedation and peripheral mononuclear cells were taken every 4 h to determine the concentration of endotoxin by flow cytometry. The results are shown in the Table.

Results
The percentage of marked mononuclear cells increased during shock. Only in the last hours before death did the rate of increase decline.

Conclusion
Preliminary data on marked mononuclear cells showed that the amount of natural incorporated endotoxin, i.e. the quantity of bound endotoxin before infusion, was 32 per cent.
Endothelins and carbon monoxide interact to regulate rat liver microcirculation after haemorrhagic shock
Authors: Rensing H , Bauer I , Pannen B H J , Paxian M , Bauer M 
Published: March 2003

Abstract

Background
Upregulation of stress-induced vascular mediators such as endothelin (ET) 1, nitric oxide synthase (NOS)–nitric oxide or the haem oxygenase (HO)–carbon monoxide pathway may contribute to altered microvascular responsiveness after ischaemia and reperfusion. A profound induction of HO-1 and an increase in portal resistance after blockade of the HO pathway has been shown to occur after haemorrhagic shock and resuscitation (H/R). This study investigated whether the observed increased portal resistance after blockade of the HO pathway was mediated by a concomitant upregulation of ET-l.

Methods
Sprague–Dawley rats (n = 10 per group) were subjected to H/R (mean arterial pressure 40 mmHg for l h, followed by 5 h of resuscitation). Expression of HO-1, inducible NOS (iNOS) and ET-1 was studied by standard Northern blot analysis and reverse transcriptase–polymerase chain reaction. At 6 h either the ET antagonist bosentan 10 mg kg−1 or vehicle was injected. After 10 min the HO pathway was blocked in all animals by tin protoporphyrin (SnPP) IX 50 μmol kg−1. Subsequently portal flow and portal pressure or sinusoidal liver blood flow (assessed by intravital epifluorescence microscopy) were measured for 30 min.

Results
A profound induction in ET-1 paralleled induced HO-1 messenger RNA (mRNA) gene expression after H/R (ET-1, mean(s.d.) 9·0(1·1)-fold; HO-1, 5·9(0·3)-fold induction at 6 h); iNOS mRNA was below the detection limit. Blockade of the HO pathway led to a significant peak increase in the portal vein resistance (ΔPVR; P &lt; 0·05). There was a trend to a lower peak increase after administration of bosentan (P = 0·07) (ΔPVR: sham SnPP-IX, 0·17(0·05) mmHg min mF−1; shock vehicle SnPP-IX, 0·57(0·15) mmHg min mF−1; shock bosentan SnPP-IX, 0·29(0·05) mmHg min mF−1). Regarding liver microcirculation, pretreatment with bosentan significantly attenuated the observed decrease in perfused sinusoids (PS) and in perfusion index (PI) after blockade of the HO pathway (shock vehicle SnPP-IX: PS 23·1(1·1) mm−1, PI 1000(134) μm3 s−1 mm−1; shock bosentan SnPP-IX: PS 28·8(1·8) mm−1, PI 1483(159) μm3 s−1 mm−1; P &lt; 0·05).

Conclusion
These results suggest a functional interaction of the unregulated vasodilator carbon monoxide and the vasoconstrictor ET-1 at the sinusoidal level in rat liver after H/R.
Elective total hip replacement surgery may be a poor model of the inflammatory response to trauma
Authors: Foëx B A , Lamb W R , Roberts T E , Hodgkinson J P , Brenchley P E C 
Published: March 2003

Abstract

Background
One of the many problems associated with studying the inflammatory response to major trauma is the variability of injuries and their severity. To overcome this problem, an assessment was made of whether elective total hip replacement (THR) surgery, which includes skeletal and muscle trauma, might provide a reliable model of the inflammatory response to trauma.

Methods
Serial venous blood samples were taken from ten patients before, during and for 24 h after THR. Sandwich immunoassays were performed to detect free and receptor-bound interleukin (IL) 6 and tumour necrosis factor (TNF) α. Whole blood was also taken from nine of the patients for in vitro incubation with endotoxin to assess white cell responsiveness.

Results
None of the patients had a measurable TNF-α response during or after surgery. Only two patients had raised IL-6 during and after surgery (maximum 145 pg ml−1). Incubation of preoperative blood samples with endotoxin resulted in TNF-α and IL-6 production. The median for TNF-α was 710 (range 416–2800) pg ml−1 and that for IL-6 was 1050 (range 121–2350) pg ml−1. Some 24 h after surgery the median for TNF-α was only 450 (range 75–1760) pg ml−1. The median IL-6 production was 950 (range 124–1840) pg ml−1. There was a reduction in in vitro TNF-α production in all nine patients (mean reduction 57 per cent; P &lt; 0·05) at 24 h. There was no significant change in in vitro IL-6 production before and after surgery. The reduction in TNF-α response indicated downregulation, which was not apparent for IL-6.

Conclusion
In this study THR did not produce the typical inflammatory response described for other forms of elective surgery. THR may not be a reliable model for studying the inflammatory response to trauma. The cement used to secure the prosthesis may have an effect on the inflammatory response.
Fluid shifts during cardiopulmonary bypass with special reference to the effects of hypothermia
Authors: Heltne J K , Koller M E , Rynning S T , Farstad M , Lurid T , Husby P 
Published: March 2003

Abstract

Background
Generalized overhydration, oedema and organ dysfunction occurs in patients undergoing open heart surgery using cardiopulmonary bypass (CPB) and hypothermia. Inflammatory reactions induced by contact between blood and the foreign surfaces of the extracorporeal circuit are commonly held responsible for the disturbances in fluid balance (‘capillary leak syndrome’). Using the CPB circuit reservoir as a fluid gauge (measuring continuous extracorporeal blood volume), fluid shifts between the intravascular and the extravascular space, and differences between normothermic and moderately hypothermic CPB, were examined.

Methods
Piglets were placed on CPB (thoracotomy) under general anaesthesia. In the normothermic group (n = 7) the core temperature was kept at 38°C before and during 2 h on CPB, whereas in the hypothermic group (n = 7) the temperature was lowered to 29°C during bypass. In addition to accurate recording of fluid during operation, the extracorporeal blood volume was kept constant by maintaining a certain blood level in the CPB circuit's reservoir. Acetated Ringer was used as priming solution in the CPB, as maintenance fluid and for adding fluid to the reservoir if necessary.

Results
Cardiac output, serum electrolytes and arterial blood gases were all similar in the two groups. Haematocrit fell significantly following the start of CPB in both groups. The reservoir fluid level fell markedly in both groups necessitating fluid supplementation. This extra fluid requirement was transient in the normothermic group, but persisted in hypothermic animals. At the end of 2 h of CPB the hypothermic animals had received seven times more extra fluid than the normothermic pigs.

Conclusion
There were strong indications of a greater fluid extravasation induced by hypothermia. The model described, using the PBC circuit reservoir as a fluid gauge, provides the opportunity for further study of fluid volume shifts, their causes and potential ways to manipulate fluid pathophysiology related to hypothermia and to PBC.
Shape and propagation of systemic pulsatile blood pressure during the evolution of porcine haemorrhagic shock
Authors: Dark P , Purdy J , Atherton J , Dodds D , Little R 
Published: March 2003

Abstract

Background
The shape and propagation of systemic pulsatile blood pressure was evaluated during the evolution of haemorrhagic shock in pigs.

Methods
Twenty-seven Saffan anaesthetized, mechanically ventilated pigs were randomized to a control group, a haemorrhage group with no resuscitation (25 per cent blood loss over 20 min) and an identical haemorrhage group but with reinfusion of shed blood over a further 20 min. Standard invasive haemodynamic monitoring was conducted, as well as digital recordings of blood pressure (via semiconductor catheter-tipped pressure transducers) at consecutive sites from the aortic arch to the femoral artery.

Results
The data are presented as time-averaged isobaric pulsatile contour plots of wave propagation from the aortic arch to the femoral artery. The colour contours encompass relative pressure measurements from the troughs of diastole (blue) to the peaks of systole (red). Distance from aortic arch to femoral artery was 50 cm in this series and the time axis travelled from left to right and over 0·7 s for each figure. Data were obtained before and after 25% haemorrhage and again after restoration of blood volume.

Conclusion
The time-domain morphology of the pulsatile blood pressure waveform and its systemic propagation is changed during a survivable haemorrhage. Furthermore, recovery is apparent following blood volume restoration.
Impact of the ‘2 week wait’ directive for suspected cancer on service provision in a symptomatic breast clinic
Authors: Cant P J , Yu D S L 
Published: March 2003

Abstract

Background
The ‘2 week wait’ directive (Health Service Circular (HSC) 1998/242) guaranteeing that ‘everyone with suspected breast cancer will be able to see a specialist within two weeks of their general practitioner (GP) deciding they need to be seen urgently’ is a unique audited approach to access for the British National Health Service, the effects of which have been assessed in a non-academic symptomatic breast clinic.

Methods
New GP referrals (n = 607) were reviewed prospectively in two comparable 3-month intervals, beginning 1 April 1998 and 1 April 1999, to determine the probability of a breast cancer diagnosis from the referral letter and the effects of the directive on waiting times for appointments and utilization of clinics.

Results
The urgency of referral was not specified in 53 per cent of GP referrals. For the ‘urgent’ cases (25 per cent of all new referrals) the probability of a final diagnosis of breast cancer was 0·19. The breast specialists prospectively achieved a rate of 0·26 from 99 per cent of the same referral letters. ‘Urgent’ referrals did not wait significantly longer in 1999 (median 9 versus 10 days) but waiting times for new appointments overall increased (13 versus 16 days; P &lt; 0·01), and this was greatest for ‘routine’ referrals (14 versus 21 days; P &lt; 0·001). These changes were caused by an increase in the number of clinic appointments, due to significant increases in median number of visits to diagnosis or discharge and clinic non-attendance in 1999, resulting in overbooking. Telephonic communications were associated with faster median access times (fax 8 days; telephone 2 days), relative to mailed referrals (19 days) (P &lt; 0·01).

Conclusion
Breast specialists were better overall at assessing the probability of a breast cancer diagnosis. The waiting time for ‘urgent’ appointments was unchanged following HSC 1998/242, but there was an increased wait for other patients, especially those assessed as having a lower probability of cancer.
Rapid rehabilitation in elderly patients after laparoscopic colonic resection
Authors: Bardram L , Funch-Jensen P , Kehlet H 
Published: March 2003

Abstract

Background
Introduction of the laparoscopic surgical technique has reduced hospital stay after colonic resection from about 8–10 to 4–6 days. In most studies, however, specific attention has not been paid to changes in perioperative protocols required to maximize the advantages of the minimally invasive procedure. In the present study the laparoscopic approach was combined with a perioperative multimodal rehabilitation protocol.

Methods
After laparoscopically assisted colonic resection, patients were treated with epidural local anaesthesia for 2 days, early mobilization and enteral nutrition. Routine use of morphine and traditional tubes, drains and prolonged bladder catheterization was avoided.

Results
Laparoscopic resection was intended in 50 consecutive patients, of median age 81 years. The conversion rate to open resection was 22 per cent. In patients in whom the procedure was completed laparoscopically the median hospital stay was 2·5 days; defaecation occurred in 92 per cent of patients within 3 days. Patients were mobilized for more than 8 h daily from day 2.

Conclusion
Recovery after colonic surgery was improved considerably by combining the use of a laparoscopic technique with a multimodal rehabilitation protocol of pain relief, early mobilization and oral nutrition.
Compliance properties of conduits used in vascular reconstruction
Authors: Tai N R , Salacinski H J , Edwards A , Hamilton G , Seifalian A M 
Published: March 2003

Abstract

Background
Compliance mismatch between native artery and prosthetic graft used for infrainguinal bypass is implicated in the aetiology of graft failure. The aim was to quantify the elastic properties of a new compliant poly(carbonate)polyurethane (CPU) vascular graft, and to compare the compliance properties of grafts made from CPU, expanded polytetrafluoroethylene (ePTFE), Dacron and human saphenous vein with that of human muscular artery.

Methods
A pulsatile flow phantom was used to perfuse vessel and prosthetic graft segments at physiological pulse pressure and flow. Intraluminal pressure was measured using a Millar Mikro-tip catheter transducer and vessel wall motion was determined with duplex ultrasonography using an echo-locked wall-tracking system. Diametrical compliance and a stiffness index were then calculated for each type of conduit over mean pressures ranging from 30 to 100 mmHg by 10-mmHg increments.

Results
The compliance values of CPU and artery (mean over the pressure range) were similar (mean(s.d.) 8·1(0·4) and 8·0(5·9) per cent per mmHg × 10−2 respectively), although the elastic behaviour of artery was anisotropic unlike CPU, which was isotropic. Dacron and ePTFE grafts had lower compliance values (1·8(1·2) and 1·2(0·3) per cent per mmHg × 10−2 respectively, averaged over the pressure range). In both these cases, compliance and stiffness differed significantly from that of artery over a mean pressure range of 30–90 mmHg. Human saphenous vein exhibited anisotropic behaviour and, although compliant at low pressure (30 mmHg), was markedly incompliant at higher pressures.

Conclusion
Compliant polyurethane grafts offer a greater degree of compliance match than either ePTFE or Dacron.
Risk factors related to operative mortality and morbidity in patients undergoing emergency gastrectomy
Authors: So J B Y , Yam A , Cheah W K , Kum C K , Goh P M Y 
Published: March 2003

Abstract

Background
Emergency gastric resection for complicated peptic ulcer and gastric cancer is a major challenge for general surgeons. This study aimed to evaluate the results of emergency gastrectomy and to examine the factors that predict the operative outcome.

Methods
A total of 82 consecutive patients who underwent emergency gastrectomy were studied. The following variables were assessed: pathology, mortality rate, morbidity, reasons for reoperation and factors related to the outcome.

Results
There were 64 men and 18 women with a median age of 62 (range 30–90) years. The indications were bleeding and perforated gastric or duodenal ulcers in 45 and 20 patients respectively, and bleeding and perforated gastric tumours in seven and ten patients respectively. The overall mortality rate was 17 per cent (n = 14). The complication rate was 63 per cent and 11 patients (13 per cent) required reoperation. By multivariate analysis, age greater than 65 years and blood haemoglobin level less than 10 g/dl on admission were predictive of complications after emergency gastrectomy. Postoperative pulmonary and cardiac complications and hypotension on admission were independent risk factors associated with operative death.

Conclusion
Age more than 65 years, haemoglobin level less than 10 g/dl and hypotension on admission were associated with a poor outcome after emergency gastrectomy. The operative result was not affected by the underlying gastric pathology.
Surgery for colorectal liver metastases with hepatic lymph node involvement: a systematic review
Authors: Rodgers M S , McCall J L 
Published: March 2003

Abstract

Background
Liver resection for colorectal metastases is the only known treatment associated with long-term survival; extrahepatic disease is usually considered a contraindication to such treatment. However, some surgeons do not regard spread to the hepatic lymph nodes as a contraindication provided that these nodes can be excised adequately. A systematic review of the literature was undertaken to address this issue.

Methods
An electronic search using Medline, Cancerlit and Embase databases was performed for studies reporting liver resection for colorectal metastases from 1964 to 1999. Data were extracted from papers reporting outcome for patients with positive hepatic nodes and analysed according to predetermined criteria.

Results
Fifteen studies were identified that gave survival data on 145 node-positive patients. Five patients were reported to have survived 5 years after liver resection; one was disease free, two had recurrent disease and the disease status was not described in the remaining two. Five studies containing 83 patients specified a formal lymph node dissection as part of the surgical procedure and four of the five node-positive 5-year survivors were from these studies.

Conclusion
There are few 5-year survivors after liver resection, with or without lymph node dissection, for colorectal hepatic metastases involving the hepatic lymph nodes.