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Biomedical subjects

M P Zalunardo

Publications and source records attributed to M P Zalunardo.

At least 19 recordsLinked to original sources
PubMed2004

Effect of rofecoxib on platelet aggregation and blood loss in gynaecological and breast surgery compared with diclofenac.

BACKGROUND: Non-selective cyclooxygenase (COX) inhibitors or non-steroidal anti- inflammatory drugs (NSAIDs) are frequently omitted for perioperative pain relief because of potential side-effects. COX-2-selective inhibitors may have a more favourable side-effect profile. This study tested the hypothesis that the COX-2-selective inhibitor rofecoxib has less influence on platelet function than the NSAID diclofenac in gynaecological surgery. In addition, analgesic efficacy and side-effects of the two drugs were compared. METHODS: In this single-centre, prospective, double-blind, active controlled study, women undergoing vaginal hysterectomy (n=25) or breast surgery (n=25) under general anaesthesia received preoperatively 50 mg of rofecoxib p.o. followed 8 and 16 h later by two doses of placebo or three doses of diclofenac 50 mg p.o. at the same time points. We assessed arachidonic acid-stimulated platelet aggregation before and 4 h after the first dose of study medication, estimated intraoperative blood loss, and haemoglobin loss until the first morning after surgery. Analgesic efficacy, use of rescue analgesics, and side-effects were also recorded. RESULTS: In the rofecoxib group, stimulated platelet aggregation was disturbed less (P=0.02), and estimated intraoperative blood loss (P=0.01) and the decrease in haemoglobin were lower (P=0.01). At similar pain ratings, the use of anti-emetic drugs was less in the rofecoxib group (P=0.03). CONCLUSION: Besides having a smaller effect on platelet aggregation, one oral dose of rofecoxib 50 mg given before surgery provided postoperative analgesia similar to that given by three doses of diclofenac 50 mg and was associated with less use of anti-emetics and less surgical blood loss in gynaecological surgery compared with diclofenac.

Adult↗
PubMed2004

Therapeutic impact of intra-operative transoesophageal echocardiography during noncardiac surgery.

The impact of transoesophageal echocardiography on haemodynamic management during elective noncardiac surgery was assessed during this observational prospective database analysis. Ninety-nine consecutive patients were studied, who were at risk of intra-operative myocardial ischaemia or haemodynamic instability (Class II indications) and were undergoing vascular, visceral or chest surgery. A total of 165 new echocardiographic findings were recorded. Based on these findings changes in drug therapy were made in 47% and changes in fluid therapy in 24% of patients. Left ventricular wall motion abnormalities were seen in 32% and other relevant diagnoses made in 10%. Echocardiography showed a significant impact on drug therapy in patients with pre-operative systolic wall motion abnormalities (vasodilators: OR = 7.1, CI 95% = 2.1/24.0; vasopressors: OR = 3.3, CI 95% = 1.2/9.1) and patients with a history of left heart failure (vasodilators: OR = 5.2, CI 95% = 1.0/31.4). Fluid therapy was significantly influenced by echocardiographic findings during liver and lung transplantation (50% compared with 24% during other surgical interventions, p < 0.05).

Aged↗
PubMed2004

Intravenous iloprost bridging to orthotopic liver transplantation in portopulmonary hypertension.

Portopulmonary hypertension (PPHTN) is associated with poor prognosis and high perioperative mortality after orthotopic liver transplantation. This study documents the first case of a patient with PPHTN who was successfully bridged to orthotopic liver transplantation with i.v. iloprost, a stable prostacyclin analogue. The PPHTN had resolved completely 4 months after successful transplantation. In conclusion, portopulmonary hypertension is a relative contraindication to orthotopic liver transplantation, which should be attempted only if pulmonary haemodynamics improve with prostanoids. In this context, iloprost may be a valuable alternative to epoprostenol.

Alcoholism↗
PubMed2002

Changes in intrathoracic blood volume associated with pneumoperitoneum and positioning.

BACKGROUND: It is still controversial whether elevated cardiac filling pressures after the onset of pneumoperitoneum are the consequence of increased intrathoracic pressure or of increased venous return. The aim of this study was to assess the effects of pneumoperitoneum and body positioning on intrathoracic blood volume (ITBV). METHODS: Thirty anesthetized patients were randomly assigned to have CO2-pneumoperitoneum (13 mmHg) either in a supine, in a 15 degrees head-up tilt or in a 15 degrees head-down tilt position. Measurements of ITBV and hemodynamics by the double indicator method were recorded after induction of anesthesia and application of a fluid bolus (Lactated Ringer's solution 10 ml/kg), after positioning and after induction of pneumoperitoneum. RESULTS: Intrathoracic blood volume index (ITBVI) increased significantly after induction of pneumoperitoneum in all body positions (supine: from 18.5 +/- 3.3 -20.2 +/- 5.2 ml/kg (+6%) head-up from 16.7 +/- 3.8 - 17.4 +/- 3.7 ml/kg (+16%) and head-down: from 19.8 +/- 5.6 - 20.5 +/- 5.9 ml/kg (+14%)). Heart rate did not change significantly in any of the groups. Cardiac index showed a statistically significant change in the head-down position with pneumoperitoneum (-11%). A good correlation was found for stroke volume (SV) with ITBV (r = 0.79), but not with central venous pressure (r = 0.26). Systemic vascular resistance index increased significantly in all three groups (supine +6%, head-up +16%, head-down position +14%). CONCLUSION: The present study indicates that the onset of pneumoperitoneum, even with moderate intra-abdominal pressures, is associated with an increased intrathoracic blood volume in ASA I/II patients.

Adult↗
PubMed2002

Late oesophageal perforation after intraoperative transoesophageal echocardiography.

Serious haemodynamic instability occurred during emergency surgery for a perforated duodenal ulcer in a 72-year-old man with acute myocardial infarction. Intraoperative transoesophageal echocardiography was crucial for diagnosis of the location of myocardial infarction in the right ventricle and the subsequent haemodynamic management. Postoperatively, a thrombus in the right coronary artery was removed by coronary angiography. The patient's trachea was extubated on the fourth postoperative day. Another 4 days later a leak in the lower oesophagus was suspected because of pleural empyema, and verified. The patient's trachea had to be re-intubated and an oesophageal stent was inserted. The patient was discharged, fully recovered, 2 months after the operation.

Aged↗
PubMed2001

Improved results after lung transplantation--analysis of factors.

Better recipient selection, sophisticated postoperative surveillance and new immunosuppressive and anti-infective regimens can improve the results of lung transplantation. We compared the results of lung transplants performed between 1992 and 1996 (early period; 47) and between 1997 and 2000 (recent period; 46) in a cohort study to assess which factors influenced survival. Estimates of relative hazards were adjusted for possible confounding effects with the use of Cox regression analysis. Overall 2-year survival was 70%. Survival by this time was significantly better in the recent period (82% vs. 60%; p = 0.0093). Acute rejection episodes and death due to BOS were less frequent in the recent period. There were no technical failures, and the cumulative incidence of BOS was low (34% at 5 years). The beneficial effect of the transplantation date 1997 or later at a hazard ratio of 0.33 (95% CI, 0.13-0.84) was materially changed only by the adjustment for ganciclovir prophylaxis (0.50; 95% CI, 0.09-2.91) and immunosuppression with mycophenolate mofetil (0.80; 95% CI, 0.27-2.36). After adjustment for both ganciclovir and mycophenolate mofetil, the beneficial time period effect was completely removed (1.24; 95% CI, 0.14-11.39). Immunosuppressive therapy with mycophenolate mofetil and use of ganciclovir prophylaxis in addition to careful postoperative surveillance and surgical expertise can lead to improved results after lung transplantation.

Adolescent↗
PubMed2001

[Cardiovascular stress protection following anesthesia induction. Comparison of clonidine and esmolol].

Alpha-2-adrenoceptor-agonists as well as cardioselective betareceptor-antagonists have been shown to blunt stress response due to tracheal intubation. The purpose of our study was to investigate,whether clonidine or esmolol is more efficient to attenuate stress response due to intubation.44 patients were randomly assigned to receive either clonidine (n=22; 3 microg/kg) or esmolol (n=22; 2 mg/kg) immediately prior to a standardized induction of anaesthesia. Heart rate, arterial blood pressure, cardiac output, epinephrine and norepinephrine plasma concentrations were measured before,during and 10 min after intubation. Blood pressure was measured invasively and cardiac output was determined by transthoracic echocardiography. Absolute values and increase of mean arterial pressure and norepinephrine plasma concentrations were significantly less in the clonidine group (p<0,05). Clonidine (3 microg/kg) is more efficient than esmolol (2 mg/kg) in blunting stress response due to endotracheal intubation.

Adrenergic alpha-Agonists↗
PubMed2001

Total intravenous anaesthesia in a patient with familial hypokalaemic periodic paralysis.

A 35-year-old woman with known familial hypokalaemic periodic paralysis received general anaesthesia for reduction of bilateral breast hyperplasia. Uncomplicated general anaesthesia was performed using a propofol target-controlled infusion, remifentanil infusion and bolus doses of mivacurium with neuromuscular function monitoring. Plasma potassium concentrations were controlled intermittently in the peri-operative period and supplemented to achieve normokalaemia. Despite continuous substitution, an episode of low plasma potassium concentration occurred during the recovery period; this was without any clinical signs of muscle paralysis or respiratory distress.

Adult↗
PubMed2001

Clonidine decreases propofol requirements during anaesthesia: effect on bispectral index.

Assessment of the effect of clonidine on depth of anaesthesia is difficult because clonidine combines analgesic, sedative and direct haemodynamic effects. We thus evaluated the influence of clonidine on the bispectral index (BIS) and its potential dose-sparing effect on propofol. After induction of anaesthesia with target-controlled infusion of propofol and obtaining an unchanged bispectral index (pre-BIS), clonidine 4 microg kg(-1) or placebo was administered randomly to 50 patients in a double-blind manner. Subsequently, if there was a decrease in BIS we reduced the target concentration of propofol until pre-BIS was reached. The pre-BIS was maintained and a remifentanil infusion was added during surgery. The courses of the BIS, heart rate and blood pressure were recorded and the total amounts of intra-operative propofol and remifentanil were determined. Assessment of implicit memory during anaesthesia was performed with an auditory implicit memory test consisting of item sequences. Administration of clonidine resulted in a decrease in the BIS from 45 (SD 4) to 40 (6) (P<0.001), which allowed a reduction of propofol target concentration from 3.3 (0.6) to 2.7 (0.7) microg ml(-1) (P<0.001) and measured propofol concentration from 2.9 (0.6) to 2.5 (0.7) kg ml(-1) (P=0.009) in order to maintain the pre-BIS value. During subsequent surgery, propofol requirements were reduced by 20% (P=0.002) in the clonidine group and a similar amount of remifentanil was used in each group. The increase in anaesthetic depth given by clonidine can therefore be measured with bispectral EEG analysis and allows reduction of the propofol dose to achieve a specific depth of anaesthesia.

Adjuvants, Anesthesia↗
PubMed2001

Isolated reduction of haematocrit does not compromise in vitro blood coagulation.

Low haematocrit values are generally well tolerated in terms of oxygen transport but a low haematocrit might interfere with blood coagulation. We thus sampled 60 ml of blood in 30 healthy volunteers. The blood was centrifuged for 30 min at 2000 g and separated into plasma, which contained the platelet fraction, and packed red blood cells. The blood was subsequently reconstituted by combining the entire plasma fraction with a mixture of packed red blood cells, 0.9% saline, so that the final haematocrit was either 40, 30, 20, or 10%. Blood coagulation was assessed by computerized Thrombelastograph analysis. Data were compared using repeated measures analysis of variance and post-hoc paired t-tests with Bonferroni correction. Decreasing the haematocrit from 40 to 10% resulted in a shortening of reaction time (r) and coagulation time (k), and an increase in angle alpha, maximum amplitude (MA) and clot strength (G) (all P<0.02). This pattern represents acceleration of blood coagulation with low haematocrit values. The isolated reduction in haematocrit, therefore, does not compromise in vitro blood coagulation.

Adult↗
PubMed2000

Preoperative clonidine attenuates stress response during emergence from anesthesia.

STUDY OBJECTIVES: To investigate whether a single preoperative IV dose of clonidine blunts the hemodynamic and hyperadrenergic responses not only to intubation, but also to extubation. DESIGN: Randomized, double-blind, placebo-controlled study. PATIENTS: 29 ASA physical status I and II patients (ages 18-65) who were scheduled for noncardiac, elective surgery. Patients were randomly assigned to either receive clonidine 3 microg/kg IV immediately before anesthesia induction or placebo. INTERVENTIONS: Insertion of a 14 G cannula in a large cubital vein for the determination of plasma catecholamines using local anesthesia. Insertion of a radial artery catheter for measuring blood pressure (BP) using local anesthesia. Transthoracic echocardiography to determine cardiac output (CO). MEASUREMENTS: Heart rate (HR), mean arterial pressure (MAP), CO, and plasma catecholamine concentrations. Measurements were performed: before induction (baseline), during intubation, 10 min after intubation, after surgery, during extubation, and 10 min after extubation. MAIN RESULTS: During intubation MAP, HR, and CO were lower in the clonidine group. Compared with baseline measurements, MAP and CO increased less in the clonidine group during intubation. During extubation, MAP was lower in the clonidine group. CO and MAP increased less as compared with baseline measurements in the clonidine group. Compared with the measurements after surgery CO less in the clonidine group during extubation (p < 0.05 for all results). CONCLUSIONS: A single preoperative IV dose of clonidine (3 microg/kg) blunts the hemodynamic responses due to extubation in noncardiac surgery of intermediate duration.

Adolescent↗
PubMed1998

Perioperative reliability of an on-site prothrombin time assay under different haemostatic conditions.

Perioperative use of laboratory coagulation assays is limited by the delay in obtaining results. The management of haemostasis during major surgical procedures requires rapid and accurate measurement of the prevailing coagulation status. In this prospective study, we have evaluated the reliability of on-site prothrombin time assessed by the portable coagulation monitor CoaguChek-Plus compared with standard laboratory assays during elective non-cardiac surgery. Sixty-two patients were assigned to one of three groups: group A = normal preoperative coagulation where minor intraoperative blood loss is expected; group B = normal preoperative coagulation where major intraoperative blood loss is expected; and group C = preoperative anticoagulation and minor intraoperative blood loss expected. On-site prothrombin time and laboratory prothrombin time showed poor correlation in group A (r2 = 0.24; bias (2 SD) 1.80 (3.34) S) and group B (r2 = 0.30; 1.43 (3.12) S). The correlation in group C was better (r2 = 0.71; 1.41 (1.92) S). We conclude that prothrombin time measured with the CoaguCheck-Plus monitor did not appear to be suitable for the management of haemostasis.

Blood Loss, Surgical↗
PubMed1998

Substantial changes in arterial blood gases during thoracoscopic surgery can be missed by conventional intermittent laboratory blood gas analyses.

UNLABELLED: Substantial and clinically relevant changes in arterial blood gases are likely to occur during thoracoscopic surgery with one-lung ventilation (OLV). We hypothesized that they may be missed when using the conventional intermittent blood gas sampling practice. Therefore, during 30 thoracoscopic procedures with OLV, the sampling intervals between consecutive intermittent laboratory blood gas analyses (BGA) were evaluated with respect to changes of PaO2, PaCO2, and pHa ([H+]) using a continuous intraarterial blood gas monitoring system. Frequency and timing of BGA were based on the clinical judgment of 16 experienced anesthesiologists who were blinded to the continuously measured values. Extreme fluctuations of PaO2 (37-625 mm Hg), PaCO2 (27-56 mm Hg), and pHa (7.24-7.51) were observed by continuous blood gas monitoring. During 63% of all sampling intervals, PaO2 decreased >20% compared with the preceding BGA value, which remained undetected by intermittent analysis. In 10 patients with a continuously measured minimal PaO2 value < or = 60 mm Hg, the preceding BGA overestimated this minimal PaO2 by > 47%. Correspondingly, PaCO2 increases of > 10% were observed in 35% of all sampling intervals, and [H+] increases of > 10% were observed in 24% of all sampling intervals. Because these blood gas changes were not reliably detected by using noninvasive monitoring and their magnitude is not predictable during OLV, intermittent BGA with short sampling intervals is warranted. In critical cases, continuous blood gas monitoring may be helpful. IMPLICATIONS: The magnitude of blood gas changes during thoracoscopic surgery with one-lung ventilation is not predictable and not reliably detected by noninvasive monitoring. Using a continuous intraarterial blood gas monitoring device, we demonstrated that intermittent laboratory blood gas analysis with short sampling intervals is warranted to detect arterial hypoxemia.

Adolescent↗
PubMed1997

Effects of intravenous and oral clonidine on hemodynamic and plasma-catecholamine response due to endotracheal intubation.

STUDY OBJECTIVE: To investigate the effects of intravenous (IV) versus oral clonidine on alterations of heart rate (HR), mean arterial pressure (MAP), cardiac output (CO), and plasma-catecholamines due to endotracheal intubation. DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: University hospital surgery operating room. PATIENTS: 33 ASA physical status I patients were randomly assigned to either receive clonidine 3 micrograms/kg IV immediately prior to anesthesia induction, clonidine 4 micrograms/kg orally 90 minutes prior to anesthesia induction, or placebo. INTERVENTIONS: Insertion of a 14 G cannula in a large cubital vein for the determination of plasma-catecholamines using local anesthesia. Insertion of a radial artery catheter for measuring blood pressure (BP) using local anesthesia. Transthoracic echocardiography determined CO. MEASUREMENTS AND MAIN RESULTS: Heart rate, MAP, CO, and plasma-catecholamine concentrations were measured. Measurements were performed prior to induction, during intubation, and 10 minutes after intubation. During endotracheal intubation, MAP was significantly lower in the IV clonidine group compared with the placebo and the oral clonidine groups. Cardiac output was significantly lower in the IV clonidine group only. In contrast to the placebo group, norepinephrine plasma concentrations did not increase in either clonidine group. Significant alterations of epinephrine plasma concentrations due to intubation were not observed in either group. Hemodynamics after intubation were not impaired by clonidine treatment. CONCLUSIONS: In conclusion, IV clonidine reduced stress response to endotracheal intubation compared with placebo. Oral clonidine at the dose used was less effective in blunting hemodynamic stress response than IV clonidine.

Administration, Oral↗
PubMed1997

Accuracy and clinical performance of a continuous intra-arterial blood-gas monitoring system during thoracoscopic surgery.

Accuracy and performance of the only currently available intra-arterial blood-gas monitoring system (Paratrend 7, PT7) were assessed in 23 patients during thoracoscopic surgery using one-lung ventilation. Over a wide range of values for arterial PO2 (6.1-61.1 kPa), PCO2 (4.1-9.5 kPa) and pH (7.19-7.50), 138 arterial blood-gas values obtained by PT7 were compared with corresponding in vitro laboratory blood-gas measurements. We found good clinical performance with the PT7 and good agreement between PT7 values and in vitro measurements for arterial PO2 (bias (1.96 SD) = 0.38 (9.52) kPa), PCO2 (0.31 (0.76) kPa) and pH (-0.017 (0.065)). Also, the bias for sequential changes between two, consecutive times was not significantly different from the ideal value of 0. We conclude that the PT7 is helpful in monitoring patients during thoracoscopy.

Adult↗