Difficulties and practices regarding information provision among Korean and Italian nurses

AIM

To investigate nurses' opinions and practices of providing information in a global context through cultural comparison.

BACKGROUND AND INTRODUCTION

Providing sufficient information to patients about nursing interventions and plans is essential for patient-centred care. While many countries have specific legislation making information delivery to patients a legal duty of nurses, no such legislation exists in both the Republic of Korea and Italy; nurses' only guidance is the deontological code.

METHODS

This was a cross-sectional survey study involving a convenience sample of 174 Korean nurses and 121 Italian nurses working in internal medicine and surgery at university hospitals. Data were collected using a self-administered questionnaire between February and November 2014. The questionnaire assessed demographic and professional characteristics, and difficulties and practices regarding information provision.

RESULTS

Korean and Italian nurses significantly differed in all demographic and professional characteristics. More Korean than Italian participants reported that their role in providing information was well explained within their teams, but both groups reported the same level and type of difficulties in delivering information. Nurses in both countries regularly informed patients about medications and nursing procedures, but provided information about nursing care plans less frequently. Few nurses frequently provided information to relatives instead of patients.

CONCLUSIONS

Despite cultural, demographic and professional differences between Korean and Italian nurses, their difficulties and practices in information delivery to patient were similar.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Hospital managers and policymakers should be aware that nurse-patient communication can be impaired by organizational factors, patient characteristics or the interaction among providers. Educational interventions and strategies are needed to increase information provision to patients about nursing care plans.

How to Study Boron Biodistribution in Liver Metastases from Colorectal Cancer

The purpose of this study was to evaluate boron distribution for a safe and effective BNCT (Boron Neutron Capture Therapy) of liver metastases. Samples both from healthy and tumour liver parenchyma were analysed, after i.v. boron administration, by: alpha particles counting under neutron irradiation; morphological analysis by standard haematoxylin-eosin staining; neutron autoradiography. Our method was unaffected by the cytological heterogeneity inside tumour nodules; it demonstrated selective boron distribution in tumour tissue and predicted estimated mean therapeutic doses in tumour and safety doses in healthy tissue. The time interval for efficient BNCT was 2 to 4 hours after i.v. boron administration.

Effect of a wound cleansing solution on wound bed preparation and inflammation in chronic wounds: a single-blind RCT

OBJECTIVE

Research into surfactant solutions for the debridement of chronic wounds suggests that surfactants may support wound bed preparation (WBP) in chronic wounds, however their efficacy has not been evaluated in randomised controlled trials (RCTs). Our aim was to assess the clinical efficacy of a propylbetaine-polihexanide (PP) solution versus normal saline (NS) solution in WBP, assessing inflammatory signs and wound size reduction in patients with pressure ulcers (PUs) or vascular leg ulcers.

METHOD

In a single-blinded randomised controlled trial (RCT) patients were randomly allocated to two groups and treated with either propylbetaine-polihexanide (PP) solution (Prontosan) or NS. Wounds were assessed using the Bates-Jensen wound assessment tool (BWAT). Assessments took place at inclusion (T0), day 7 (T1), day 14 (T2), day 21 (T3), and day 28 (T4). Outcomes were analysed using a two-tailed Student's t-test.

RESULTS

A total of 289 patients were included. Both groups had similar demographics, clinical status, and wound characteristics. Data analysis showed statistically significant differences between T0 and T4 for the following outcomes: BWAT total score, p=0.0248; BWAT score for inflammatory items, p=0.03; BWAT scores for wound size reduction (p=0.049) and granulation tissue improvement (p=0.043), all in favour of PP. The assessment of pain did not show any significant difference between the two groups.

CONCLUSION

The study results showed significantly higher efficacy of the PP solution versus NS solution, in reducing inflammatory signs and accelerating the healing of vascular leg ulcers and PUs. This evidence supports the update of protocols for the care of chronic wounds.

DECLARATION OF INTEREST

The authors have no conflict of interest regarding this research. This is an investigator initiated trial. B. Braun Milano SpA kindly provided the material under investigation for both treatment groups, and paid the Ethics Committees' application fees in all participating centres.

Influence of the site of measurement on the ability of plethysmographic variability index to predict fluid responsiveness

BACKGROUND

Plethysmographic variability index (PVI) is an accurate predictor of fluid responsiveness in mechanically ventilated patients. However, the site of measurement of the plethysmographic waveform impacts its morphology and its respiratory variation. The goal of this study was to investigate the ability of PVI to predict fluid responsiveness at three sites of measurement (the forehead, ear, and finger) in mechanically ventilated patients under general anaesthesia.

METHODS

We studied 28 subjects after induction of general anaesthesia. Subjects were monitored with a pulmonary artery catheter and three pulse oximeter sensors (the finger, ear, and forehead). Pulse pressure variation, central venous pressure, cardiac index (CI), and PVI measured at the forehead, ear, and finger (PVI(forehead), PVI(ear), and PVI(finger)) were recorded before and after fluid loading (FL). Subjects were responders to volume expansion if CI increased >15% after FL.

RESULTS

Areas under the receiver-operating curves to predict fluid responsiveness were 0.906, 0.880, and 0.836 for PVI(forehead), PVI(ear), and PVI(finger), respectively (P<0.05). PVI(forehead), PVI(ear), and PVI(finger) had a threshold value to predict fluid responsiveness of 15%, 16%, and 12% with sensitivities of 89%, 74%, and 74% and specificities of 78%, 74%, and 67%, respectively.

CONCLUSIONS

PVI can predict fluid responsiveness in anaesthetized and ventilated subjects at all three sites of measurement. However, the threshold values for predicting fluid responsiveness differ with the site of measurement. These results support the use of this plethysmographic dynamic index in the cephalic region when the finger is inaccessible or during states of low peripheral perfusion.

Neutron autoradiography imaging of selective boron uptake in human metastatic tumours

The ability to selectively hit the tumour cells is an essential characteristic of an anti-tumour therapy. In boron neutron capture therapy (BNCT) this characteristic is based on the selective uptake of (10)B in the tumour cells with respect to normal tissues. An important step in the BNCT planning is the measurement of the boron concentration in the tissue samples, both tumour and healthy. When the tumour is spread through the healthy tissue, as in the case of metastases, the knowledge of the different kinds of tissues in the sample being analysed is crucial. If the percentage of tumour and normal tissues cannot be evaluated, the obtained concentration is a mean value depending on the composition of the different samples being measured. In this case an imaging method that could give information both on the morphology and on the spatial distribution of boron concentration in the sample would be a fundamental support. In this paper, the results of the boron uptake analysis in the tumour and in the healthy samples taken from human livers after boron phenylalanine (BPA) infusion are shown; boron imaging was performed using neutron autoradiography.

Sevoflurane preconditioning at 1 MAC only provides limited protection in patients undergoing coronary artery bypass surgery: a randomized bi-centre trial † ‡

BACKGROUND

Volatile agents can mimic ischaemic preconditioning leading to a decrease in myocardial infarct size. The present study investigated if a 15 min sevoflurane administration before cardiopulmonary bypass (CPB) has a cardioprotective effect in patients undergoing coronary surgery.

METHODS

Seventy-two patients were randomized in two centres. The intervention group (S) received 1 MAC sevoflurane administrated via the ventilator for 15 min followed by a 15 min washout before CPB, the control group did not. The primary outcome was the postoperative troponin Ic peak. A biopsy of the atrium was taken during canulation for enzyme dosages. Results are expressed as mean (SD).

RESULTS

Neither troponin Ic nor tissular enzyme measurement exhibited any difference between the groups: peak of troponin Ic was 4.4 (5.6) in S group vs 5.2 (6.6) ng ml(-1) in control group (ns). Intratissular ecto-5'-nucleotidase activity was 7.1 (4.3) vs 8.5 (11.9), protein kinase C activity was 27.1 (15.7) vs 29.2 (28.7), tyrosine kinase activity was 101 (54.1) vs 98.5 (63.3), and P38 MAPKinase activity was 131.1 (76.1) vs 127.1 (86.8) nmol mg protein(-1) min(-1) in S group and control group, respectively (ns). However there were fewer patients with low postoperative cardiac index in S group (11% in S vs 35% in control group, P < 0.05) when considering the per protocol population. In S group, 25% of patients required an inotropic support during the postoperative period, vs 36% of patients in control group (ns).

CONCLUSIONS

This study did not show a significant preconditioning signal after 15 min of sevoflurane administration. The 15 min duration might be too short or the concentration of sevoflurane too low to induce cardioprotection detected by troponin I levels.

Préconditionnement myocardique induit par les agents anesthésiques halogénés : bases fondamentales et implications cliniques

OBJECTIVE

Volatile halogenated anaesthetics offer a myocardial protection when they are administrated before a myocardial ischaemia. Cellular mechanisms involved in anaesthetic preconditioning are now better understood. The objectives of this review are to understand the anaesthetic-induced preconditioning underlying mechanisms and to know the clinical implications.

DATA SOURCES

References were obtained from PubMed data bank (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi) using the following keywords: volatile anaesthetic, isoflurane, halothane, sevoflurane, desflurane, preconditioning, protection, myocardium.

DATA SYNTHESIS

Ischaemic preconditioning (PC) is a myocardial endogenous protection against ischaemia. It has been described as one or several short ischaemia before a sustained ischemia. These short ischaemia trigger a protective signal against this longer ischaemia. An ischemic organ is able to precondition a remote organ. It is possible to replace the short ischaemia by a preadministration of halogenated volatile anaesthetic with the same protective effect, this is called anaesthetic PC (APC). APC and ischaemic PC share similar underlying biochemical mechanisms including protein kinase C, tyrosine kinase activation and mitochondrial and sarcolemnal K(ATP) channels opening. All halogenated anaesthetics can produce an anaesthetic PC effect. Myocardial protection during reperfusion, after the long ischaemia, has been shown by successive short ischaemia or volatile anaesthetic administration, this is called postconditioning. Ischaemic PC has been described in humans in 1993. Clinical studies in human cardiac surgery have shown the possibility of anaesthetic PC with volatile anaesthetics. These studies have shown a decrease of postoperative troponin in patient receiving halogenated anaesthetics.

Effect of diaspirin cross-linked haemoglobin (DCLHb) on mean arterial pressure during cardiopulmonary bypass in swine

Diaspirin cross-linked haemoglobin (DCLHb) is a haemoglobin-based oxygen carrier which had been proposed as a resuscitative solution to replace red cell transfusion in many clinical situations. The present study was designed to evaluate the effect of different volumes of DCLHb 10% (1, 5 and 10 mL kg-1) on the cardiovascular system during cardiopulmonary bypass (CPB), and to determine the effect of DCLHb (18 mL kg-1) when added directly to the CPB prime in anaesthetized swine. DCLHb, when used as a priming solution, induced a significant increase (around 20%) in mean arterial pressure (MAP), which persisted during the entire period of CPB (P < 0.05) as compared with controls. Administration of increasing doses of DCLHb during the time course of CPB resulted in a progressive increase in MAP (P < 0.05), suggesting a linear dose-response relationship. Nicardipine, a calcium channel blocker, returned MAP to baseline. Finally, weaning of CPB was easier in animals that received DCLHb, thereby suggesting a potential protective effect of free haemoglobin in this particular clinical situation.

Pharmacological preconditioning: comparison of desflurane, sevoflurane, isoflurane and halothane in rabbit myocardium

BACKGROUND

Recent investigations showed that isoflurane can induce pharmacological preconditioning. The present study aimed to compare the potency of four different halogenated anaesthetics to induce preconditioning.

METHODS

Anaesthetized open-chest rabbits underwent 30 min of coronary artery occlusion followed by 3 h of reperfusion. Before this, rabbits were randomized into one of five groups and underwent a treatment period consisting of either no intervention for 45 min (control; n = 10), or 30 min of 1 MAC halogenated anaesthetic inhalation followed by 15 min of washout. End-tidal concentrations of halogenated agents were 3.7% for sevoflurane (n = 11), 1.4% for halothane (n = 9), 2.0% for isoflurane (n = 11), and 8.9% for desflurane (n = 11). Area at risk and infarct size were assessed by blue dye injection and tetrazolium chloride staining.

RESULTS

Mean (SD) infarct size was 54 (18)% of the risk area in untreated controls and 40 (18)% in the sevoflurane group (P > 0.05, ns). In contrast, mean infarct size was significantly smaller in the halothane, isoflurane, and desflurane groups: 26 (18)%, 32 (18)% and 16 (17)%, respectively (P < 0.05 vs control).

CONCLUSIONS

Halothane, isoflurane and desflurane induced pharmacological preconditioning, whereas sevoflurane had no significant effect. In this preparation, desflurane was the most effective agent at preconditioning the myocardium against ischaemia.

Safety of oral nicorandil before coronary artery bypass graft surgery

Nicorandil is a K(ATP) channel opener used to treat angina. It is cardioprotective and a vasodilator. We conducted a prospective, randomized, double-blind, placebo-controlled study to assess oral nicorandil in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). Twenty-two patients received nicorandil (10 mg twice a day) and 23 patients received placebo. Haemodynamic data were recorded before induction of anaesthesia (T0), 5 and 20 min after starting mechanical ventilation (T1, T2), before aortic cannulation (T3), after 30 min of CPB (T4), 10 min after CPB (T5) and after 3, 8 and 18 h in the intensive care unit (T6, T7, T8). Serum proteins (creatine kinase metabolite and cardiac troponin I) were measured before and 8 and 18 h after surgery. Haemodynamic values did not differ between the two groups. There was no tachycardia during the study, no significant difference in hypotensive episodes, ST segment changes and no changes in cardiac enzymes. Myocardial infarction after surgery was similar in the two groups. Vasoactive therapy was similar in the two groups. Nicorandil can be continued safely up to premedication without deleterious haemodynamic consequences, but a myocardial protective effect of nicorandil in CABG surgery was not found.

Evaluation of a new preservative solution for cardiac graft during hypothermia

BACKGROUND

Reports conflict on the beneficial effects of several cardioplegic solutions such as University of Wisconsin and St. Thomas' Hospital solutions. Therefore our objective was to assess the efficacy of several cardioplegic solutions for cardiac preservation by comparing University of Wisconsin modified solution (UW-1 and UW-1 + calcium = UW-2), St. Thomas' Hospital solution N degrees 1 (STH-1), Celsior solution, and a solution from our laboratory, Lyon preservation solution (LYPS).

METHODS

We randomized male rats (n = 70) to 7 groups: LYPS, Celsior, STH-1, UW-1, UW-2, normal saline solution, and control. All hearts, except control hearts were preserved by cold storage (8 hours, 4 degrees C) in the various solutions. We used isolated non-working-heart preparations (left ventricular function evaluation, n = 5/group) or biopsy specimens (energetic store evaluation, n = 5/group) to assess quality of heart preservation.

RESULTS

Hearts stored with the saline solution had a mean left ventricular developed pressure (LVDP) of 3.6 +/- 1.3 mm Hg. In contrast, LYPS and Celsior hearts had mean LVDP close to that of the control hearts (97 +/- 2.6, 92.1 +/- 2.2, and 122 +/- 1.9 mm Hg, respectively), whereas STH-1, UW-1, and UW-2 hearts presented an intermediate functional response (48 +/- 4, 39.9 +/- 4.1, and 69 +/- 1.8 mm Hg, respectively). The STH-1 and saline hearts showed increased release of creatine kinase (541.9 +/- 168 and 1,080.8 +/- 126.2 UI/liter, respectively). The energetic charge (EC = [(0.5 ADP + ATP)/ATP + ADP + AMP]) in Celsior, UW-2, and saline was significantly lower (p < 0.001) than in the other groups.

CONCLUSION

The composition of the preservation solutions had a notable effect on myocardial viability. Our results indicated that LYPS and Celsior solutions had comparable efficacy for left ventricular function. However these solutions may offer better preservation than do UW-1, UW-2, or STH-1 solutions.

Prevention of isoflurane-induced preconditioning by 5-hydroxydecanoate and gadolinium: possible involvement of mitochondrial adenosine triphosphate-sensitive potassium and stretch-activated channels

BACKGROUND

Both mitochondrial adenosine triphosphate-sensitive potassium (MKATP) channels (selectively blocked by 5-hydroxydecanoate) and stretch-activated channels (blocked by gadolinium) have been involved in the mechanism of ischemic preconditioning. Isoflurane can reproduce the protection afforded by ischemic preconditioning. We sought to determine whether isoflurane-induced preconditioning may involve MKATP and stretch-activated channels.

METHODS

Anesthetized open-chest rabbits underwent 30 min of coronary occlusion followed by 3 h of reperfusion. Before this, rabbits were randomized into one of six groups and underwent a treatment period consisting of either no intervention for 40 min (control group; n = 9) or 15 min of isoflurane inhalation (1.1% end tidal) followed by a 15-min washout period (isoflurane group; n = 9). The two groups received an intravenous bolus dose of either 5-hydroxydecanoate (5 mg/kg) or gadolinium (40 micromol/kg) before coronary occlusion and reperfusion (5-hydroxydecanoate, n = 9; gadolinium, n = 7). Two additional groups received 5-hydroxydecanoate or gadolinium before isoflurane exposure (isoflurane-5-hydroxydecanoate, n = 10; isoflurane-gadolinium, n = 8). Area at risk and infarct size were assessed by blue dye injection and tetrazolium chloride staining.

RESULTS

Area at risk was comparable among the six groups (29 +/- 7, 30 +/- 5, 27 +/- 6, 35 +/- 7, 31 +/- 7, and 27 +/- 4% of the left ventricle in the control, isoflurane, isoflurane-5-hydroxydecanoate, 5-hydroxydecanoate, isoflurane-gadolinium, and gadolinium groups, respectively). Infarct size averaged 60 +/- 20% (SD) in untreated controls versus 54 +/- 27 and 65 +/- 15% of the risk zone in 5-hydroxydecanoate- and gadolinium-treated controls (P = nonsignificant). In contrast, infarct size in the isoflurane group was significantly reduced to 26 +/- 11% of the risk zone (P < 0.05 vs.control). Both 5-hydroxydecanoate and gadolinium prevented this attenuation: infarct size averaged 68 +/- 23 and 56 +/- 21% of risk zone in the isoflurane-5-hydroxydecanoate and isoflurane-gadolinium groups, respectively (P = nonsignificant vs.control).

CONCLUSION

5-Hydroxydecanoate and gadolinium inhibited pharmacologic preconditioning by isoflurane. This result suggests that MKATP channels and mechanogated channels are probably involved in this protective mechanism.

[Evaluation of a new preservation solution for hypothermic heart transplant]

AIM

One of the major problems encountered in heart transplant is the limited cardiac preservation time. The time limit from the moment the donor heart is removed to the transplant itself is 4-6 hours at maximum. Extending the preservation time would therefore provide access to a larger pool of donors, and also permit long-distance (transfrontier) organ transfer. To attain this aim, a number of different cardiac preservation solutions have been proposed and evaluated either clinically or experimentally; however, no consensus has yet been reached by the various heart transplant teams involved. As finding an optimal solution is of major importance, the aim of the present study was therefore to assess the efficacy of several cardiac preservation solutions: the University of Wisconsin solutions (UW-1 and UW-1 + calcium = UW-2), the Saint-Thomas' Hospital solution (STH-1) and a new solution (NS) developed by our laboratory.

METHOD

Male Wistar rats (n = 60) were anesthetized by i.m. injection of pentobarbitol, and randomized into six groups, i.e., NS (group I), STH-1 (group II), UW-1 (group III), UW-2 (group IV), saline solution, NaCl (group V), and controls (group VI). All the hearts except those in the control group were preserved by immersion (8 hours, 4 degrees C) in the different solutions (n = 10/group). The hearts were either a) reperfused in Langendorff mode (functional assessment, n = 5/group); or b) frozen (energetic assessment, n = 5/group).

RESULTS

The hearts treated with NaCl displayed arrhythmia and a collapsed mean left ventricular pressure throughout the reperfusion period (3.6 +/- 1.3 mmHg) compared to the NS hearts and the control group (97 +/- 2.6 and 122 +/- 1.9 respectively), while the STH-1, UW-1 and UW-2 hearts showed an intermediate-range ventricular function (48 +/- 4; 39.9 +/- 4.1; and 69 +/- 1.8 respectively). Creatine kinase levels were higher in the STH-1 and NaCl groups (541.9 +/- 168 and 1,080.8 +/- 126.2 IU/L respectively). The energetic charge was significantly lower in the NaCl and UW-2 groups (P = 0.001) compared to the control, NS, STH-1 and UW-1 groups.

CONCLUSION

It was found that the composition of the respective solutions had a major effect on the the quality of myocardial preservation. Compared to the other solutions tested in this study, the NS solution was found to be optimal for the preservation of isolated hypothermic rat hearts.

Microperfusion techniques for long-term hypothermic preservation

BACKGROUND

The aim of this study was to compare several methods of hypothermic heart preservation.

METHODS

We preserved isolated pig hearts for 24 hours in cold cardioplegia (4 degrees C), using either continuous microperfusion (Group I) or simple storage (Group II), and with a new preservative solution (NPS, groups IA and IIA) vs St. Thomas' solution (groups IB and IIB). The main characteristics of the NPS include (1) prevention of cell swelling with polyethelene glycol (PEG), (2) low calcium and magnesium, and (3) presence of metabolic substrates, such as glucose, insulin, pyruvate, aspartate, alanyl-glutamine, and membrane stabilization compounds such as ethanol and chlorpromazine.

RESULTS

The 4 above groups were compared with hearts harvested and immediately reperfused (control group). During preservation, only Group IB showed significant edema (40% +/- 8.4% water gain). Adenylate charge was 25% to 50% higher in microperfused Groups IA and IB (0.678 +/- 0.049 and 0.795 +/- 0.071, respectively) as compared with simple-storage groups IIA and IIB (0.605 +/- 0.048 and 0.524 +/- 0.160, respectively). Ultrastructural analysis showed that tissue injury occurred mainly in Group IIB (altered mitochondria, chromatin clumping). Functional data showed better recovery of NPS groups as compared with St. Thomas groups: coronary flow was identical in Group IB and control (57.8 +/- 22 and 56.6 +/- 14 ml/min/100 g, respectively), and in IA > IB (p < 0.001) and IIA > IIB (p < 0.01); the rate pressure products were higher in NPS groups compared with St. Thomas groups (IA > IB, p < 0.01); IIA > IIB, p < 0.05).

CONCLUSIONS

The microperfusion method associated with the NPS provides excellent protection in long-term hypothermic heart preservation.

Biphasic response after brain death induction: prominent part of catecholamines release in this phenomenon

BACKGROUND

The physiopathology of hemodynamic instability that occurs after brain death remains unknown. The aim of this study was to examine the initial response to brain death induction.

METHODS

After anesthesia and monitoring, 16 pigs were randomized into a control group (C, n = 8) and a brain death group (BD, n = 8). We inflated a subdural catheter balloon to induce brain death. We analyzed hemodynamic and plasmatic biochemical data for 180 minutes after brain death induction. Energetic compounds were measured. We expressed the results in comparison with the C group.

RESULTS

The C group remained stable. One minute after brain death, the Cushing reflex appeared, with a hyperdynamic response to plasma catecholamines levels increasing (norepinephrine and epinephrine, 3.1-fold, p = 0. 02, and 3.8-fold, p = 0.07, respectively). After a return to baseline, we recorded a second hyperdynamic profile 120 minutes later. At this time, a second peak of catecholamines appeared (6. 3-fold, p = 0.04, and 9.1-fold, p = 0.02, concerning norepinephrine and epinephrine). At the same time, we observed brief myocardial lactate production (+175%, p < 0.01), with a rise of troponine I (+64%, p = 0.03). The energetic index was similar in both groups: 0. 85 (+/-0.02) in the C group vs 0.87 (+/-0.02) in the BD group.

CONCLUSIONS

In this model, biphasic plasmatic catecholamine release appears to primarily explain the physiopathology of the hemodynamic response to brain death induction.

Effect of cardiopulmonary bypass on serum procalcitonin and C-reactive protein concentrations

We have measured serum procalcitonin (PCT) concentrations after cardiac surgery in 36 patients allocated to one of three groups: group 1, coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) (n = 12); group 2, CABG without CPB (n = 12); and group 3, valvular surgery with CPB (n = 12). Serum PCT and C-reactive protein (CRP) concentrations were measured before operation, at the end of surgery and daily until postoperative day 8. Serum PCT concentrations increased, irrespective of the type of cardiac surgery, with maximum concentrations on day 1: mean 1.3 (SD 1.8), 1.1 (1.2) and 1.4 (1.2) ng ml-1 in groups 1, 2 and 3, respectively (ns). Serum PCT concentrations remained less than 5 ng ml-1 in all patients. Concentrations returned to normal by day 5 in all groups. To determine the effect of the systemic inflammatory response (SIRS) on serum PCT concentrations, patients were divided post hoc, without considering the type of cardiac surgery, into patients with SIRS (n = 19) and those without SIRS (n = 17). The increase in serum PCT was significantly greater in SIRS (peak PCT 1.79 (1.64) ng ml-1 vs 0.34 (0.32) ng ml-1 in patients without SIRS) (P = 0.005). Samples for PCT and CRP measurements were obtained from 10 other patients with postoperative complications (circulatory failure n = 7; active endocarditis n = 2; septic shock n = 1). In these patients, serum PCT concentrations ranged from 6.2 to 230 ng ml-1. Serum CRP concentrations increased in all patients, with no differences between groups. The postoperative increase in CRP lasted longer than that of PCT. We conclude that SIRS induced by cardiac surgery, with and without CPB, influenced serum PCT concentrations with a moderate and transient postoperative peak on the first day after operation. A postoperative serum PCT concentration of more than 5 ng ml-1 is highly suggestive of a postoperative complication.

Effects of propofol on haemodynamics and on regional blood flows in dogs submitted or not to a volaemic expansion

This study was designed to examine the effect of volume loading on haemodynamic responses and regional cardiac function in dogs subjected to two infusion rates of propofol. Instrumentation was established to measure aortic and left ventricular pressures, cardiac output and myocardial segmental lengths. Measurements were taken during two successive infusion rates of propofol: 0.2 (P0.2) and 0.4 (P0.4) mg kg-1 min-1. One group (VL +) (n = 6) received volume loading (dextran 40, 10 mL kg-1 h-1), the other group (VL-) (n = 6) received only basal perfusion (Ringer solution, 2 mL kg-1.h-1). Regional blood flows were measured by radio-labelled microspheres. P0.4 induced a decrease in cardiac output and in dP/dtmax. End-diastolic length decreased with propofol without any difference between groups. Regional contractility was not modified by propofol or by volume loading. P0.4 decreased endocardial and epicardial blood flow in the VL-group only. Renal, small intestine and large intestine blood flows decreased in both groups with P0.4. P0.2 did not alter regional blood flows significantly. It was concluded that in this model, propofol infusion at 0.4 mg kg-1 min-1 induced splanchnic, renal and myocardial hypoperfusion in animals not submitted to a mild fluid loading. Fluid loading allowed myocardial perfusion to be maintained but could not prevent a marked decrease in splanchnic and renal perfusion.

[Minimally invasive cardiac surgery: surgical techniques and anesthetic problems]

OBJECTIVE

To review current data on minimally invasive cardiac surgery.

DATA SOURCES

Search through the Medline data base of French or English articles.

DATA EXTRACTION

The articles were analysed to make a synthesis of the various techniques with their main indications and contra-indications.

DATA SYNTHESIS

Minimally invasive cardiac surgery includes various surgical procedures. The usual techniques are described, their major benefits and drawbacks are discussed. The main goals of anaesthetic management are preservation of ventricular function and systemic perfusion, detection and treatment of myocardial ischaemia, prevention of hypothermia in case of coronary artery bypass grafting on the beating heart via sternotomy, intermittent selective ventilation of the collapsed lung using CPAP in case of limited thoracotomy. Expertise in transoesophageal echocardiography is essential for insertion and checking the accurate positioning of the various catheters of the endovascular CPB Heartport system (pulmonary vent, endosinus catheter, venous cannula, endoaortic clamp) allowing coronary artery bypass grafting and mitral valve surgery through limited thoracotomy and finally, detection of retained intracardiac air and assessment of complete clearing of cardiac cavities after mitral valve surgery through limited thoracotomy and aortic valve surgery via ministernotomy. Short-acting anaesthetic agents allow rapid recovery from anaesthesia, early extubation and discharge to the surgical ward within 24 h, whereas overall time spent in the operating room is often longer than with conventional cardiac surgery.

[Severe digestive complications after heart surgery using extracorporeal circulation]

PURPOSE

To determine the incidence, circumstances of occurrence and evolution of gastrointestinal complications after cardiac surgery with extracorporeal circulation (ECC).

METHODS

Retrospective chart study of gastrointestinal complications in 6.281 patients undergoing ECC between january 1994 and December 1997.

RESULTS

Sixty patients developed 68 gastrointestinal complications (1%). Complications included: upper gastrointestinal bleeding (n = 23), intestinal ischemia (n = 19), cholecystitis (n = 7), pancreatitis (n = 6), and paralytic ileus (n = 16). The incidence of these complications was low after coronary artery (0.4%) or valvular surgery (0.8%) and high after cardiac transplantation (6%) and after surgery for acute aortic dissection (9%). Compared with a control population, patients with gastrointestinal complication had a higher Parsonnet score (29 +/- 15 vs 13 +/- 12 points; P = 0.002), were more frequently operated upon as an emergency (40/60, 66% vs 1120/6221, 18%; P = 0.01), underwent ECC of longer duration (114 +/- 66 vs 74 +/- 42 min; P = 0.01), and presented more frequently with low cardiac output after surgery (45/60, 75% vs 435/6221, 7%; P = 0.001). The mortality rate after gastrointestinal complications was 52%. The major factor associated with mortality was the occurrence of sepsis (OR = 38.7). Other factors were: renal failure (OR = 7.9), age > 75 yr (OR = 3.5), mechanical ventilation for more than seven days (OR = 2.7), associated cerebral damage (OR = 3.9).

CONCLUSION

Gastrointestinal complications after ECC occur in high risk surgical patients. These complications are frequently associated with other complications leading to a high mortality rate.

An ultrastructural and cytochemical study of the mesonephros of Rana esculenta during activity and hibernation

The biological cycle of most amphibians undergoes seasonal variations. In this study, we investigated the mesonephros of Rana esculenta during active life and the natural hibernation period. The ultrastructural morphology of the different tracts constituting the nephron was analysed. Moreover, to evaluate the effect of seasonal temperature variations on the mesonephros function, the activity of some enzymes linked to membrane transport and playing regulatory roles in various metabolic pathways was investigated in different tracts of the frog nephron. During hibernation the glomerular filtration barrier appeared thicker than in the active life, lysosomes and paraplasmatic material, mostly glycogen, being accumulated in the proximal and distal tubule cells respectively. Cytoplasmic organelles, i.e., mitochondria, endoplasmic reticulum were observed in segregated areas. At the same time, changes in some enzyme activities were noted. The activity of some membrane-transport enzymes (5' nucleotidase and K+-p-nitrophenyl phosphatase) and of energetic metabolism (succinic dehydrogenase) was reduced. Nevertheless the alkaline phosphatase activity was not changed significantly, and this suggests that some metabolic activities were preserved in the hibernating samples. These results indicate morpho-functional adaptations of the kidney cells that preserve their role in osmoregulation and some metabolic processes, even during unfavourable seasons.