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C Gomar

Publications and source records attributed to C Gomar.

At least 37 records · Page 2Linked to original sources
PubMed2001

Gas exchange and pulmonary hemodynamics during lung resection in patients at increased risk: relationship with preoperative exercise testing.

STUDY OBJECTIVES: To evaluate the intraoperative evolution of patients with COPD during lung resection and to test whether exercise testing could be helpful in the prediction of the intraoperative course. DESIGN: Prospective study. SETTING: University teaching hospital. PATIENTS: Forty patients (mean [+/- SD] age, 65 +/- 9 years) with COPD (ie, FEV(1), 55 +/- 11% of predicted) and resectable lung neoplasms. INTERVENTIONS: Preoperatively, pulmonary function testing, quantitative lung perfusion scanning, and exercise performance testing were administered. Intraoperatively, pulmonary, hemodynamic, and blood gas measurements were performed at five stages, including periods of two-lung ventilation (TLV) and periods of one-lung ventilation (OLV). RESULTS: During OLV, compared with TLV, the PaO(2)/fraction of inspired oxygen (FIO(2)) ratio decreased from 458 +/- 120 to 248 +/- 131 mm Hg (p < 0.05), whereas pulmonary artery pressure (PAP) increased from 18 +/- 5 to 23 +/- 5 mm Hg (p < 0.05). Cardiac output (t) also increased from 4.0 +/- 1.2 to 5.1 +/- 1.9 L/min (p < 0.05), yielding to a higher mixed venous PO(2). Both PaO(2) and t during OLV were significantly lower in patients who had undergone right thoracotomies compared with those who had undergone left thoracotomies. The PaO(2)/FIO(2) ratio during OLV correlated with the PaO(2) during exercise (r = 0.39; p = 0.01) and with the perfusion of the non-neoplastic lung (r = 0.44; p = 0.005). CONCLUSIONS: In COPD patients, OLV leads to a significant derangement of gas exchange, which is more pronounced in right thoracotomies. Preoperative measurement of PaO(2) during exercise and the distribution of perfusion by lung scan might be useful to identify those patients who are at the greatest risk of abnormal gas exchange during lung resections.

Aged↗
PubMed2001

Plasma magnesium in patients submitted to cardiac surgery and its influence on perioperative morbidity.

BACKGROUND: To determine the changes in magnesaemia in cardiac surgical patients submitted to cardiopulmonary bypass (CPB) and their influence on perioperative morbidity. METHODS SETTING: the cardiovascular surgery department of a university hospital. PATIENTS: 60 patients of both sexes, mean age 60+/-12 yrs, operated on consecutively for myocardial revascularization or valve replacement. INTERVENTIONS: plasma Mg2+ levels were measured preoperatively, during CPB, postCPB and throughout the first 24 hrs after operation. Preoperative plasma Mg2+ levels of these patients were compared with those of 15 non-cardiac surgical patients and 11 healthy volunteers. RESULTS: Mean values of Mg2+ similar in the three populations although in the group of cardiac patients the number of hypomagnesaemic patients was significantly higher (16 patients=26.6%). In these 16 patients, preoperative hypomagnesaemia had a statistically significant relationship with the preoperative treatment with beta-blockers and previous history of arrhythmias (p<0.05). A progressive statistically significant decrease of Mg2+ was observed throughout the surgery that remained low at 24 hours postoperatively (p<0.05). Normomagnesemic patients needed significantly more shocks and electrical energy to obtain heart defibrillation after CPB. The incidence of both postoperative arrhythmias and postoperative low cardiac index (<2.5 L.m2) was statistically significantly more frequent in hypomagnesaemic patients (p<0.05). CONCLUSIONS: Preoperative hypomagnesaemia was more frequent in this small sample of cardiac surgical patients than in non-cardiac surgical patients and was related to preoperative treatment with b-blockers. Hypomagne-saemia caused by CPB persisted 24 hrs after operation and was associated with higher incidence of both postoperative arrhythmias and low cardiac index.

Adrenergic beta-Antagonists↗
PubMed2000

Epidural analgesia-anaesthesia in obstetrics.

Epidural analgesia is the most effective and innocuous technique for obstetrics. Pain relief is its main indication but maternal diseases that might be decompensated by labour and delivery are also accepted indications. Low doses of long-acting local anaesthetics alone or in combination with low doses of fentanyl or sufentanil provide good quality analgesia and are safe for mother and fetus. Test doses in parturients lack sufficient specificity and sensitivity for detecting inadvertent intravascular injection, and subarachnoid migration of the catheter is possible at any time during the procedure. Therefore, every injection must be considered as a test dose and only fractionated injections must be made. Epidural block to T10 is needed for labour and to level T4 for Caesarean section. Maintenance of the block with a continuous infusion, or patient-controlled epidural analgesia with a background continuous infusion, provides more stable analgesia than by intermittent injection. Technical difficulties, dural tap, bloody tap, hypotension and insufficient block are most frequent complications of epidural block in obstetrics. Excessive motor block prolongs the second stage of labour and increases the frequency for instrumental delivery and is therefore considered a complication.

Analgesia, Epidural↗
PubMed2000

[Effectiveness of isobaric 0.5% bupivacaine and 5% lidocaine in continuous subarachnoid anesthesia with microcatheters].

OBJECTIVES: To study the clinical effect of two isobaric local anesthetics infused through microcatheters for continuous subarachnoid anesthesia. MATERIAL AND METHODS: Patients undergoing surgery under continuous subarachnoid anesthesia were enrolled prospectively over 12 months. Twenty-seven-gage catheters were inserted through 22 G Sprotte (Intralong) needles. The two isobaric anesthetics (0.5% bupivacaine and 5% lidocaine) were studied in two successive six-month periods. One milliliter of local anesthetic was administered, followed by incremental doses of 0.5 ml until the required anesthetic level was reached. Hemodynamic variables were recorded, as were levels of anesthetic and motor blockade and complications developing during the surgical and postoperative periods. RESULTS: Thirty-one patients were anesthetized with isobaric 0.5% bupivacaine and 40 with isobaric 5% lidocaine. A high blockade was observed in three patients in the bupivacaine group and in 15 in the bupivacaine group (p < 0.05). The highest anesthetic level reached was T4. Hypotension occurred in one patient in the bupivacaine group and in 10 in the lidocaine group (p < 0.05). Blockade was difficult to increase to the appropriate level in 11 lidocaine patients and in one bupivacaine patient, whereas blockade of distal roots was difficult in 13 bupivacaine patients and in 7 lidocaine patients (p < 0.005). The total doses infused were 11.0 +/- 3.0 mg of 0.5% bupivacaine and 95.6 +/- 24.6 mg of 5% lidocaine. CONCLUSIONS: Isobaric 0.5% bupivacaine provides a more predictable anesthetic blockade with greater hemodynamic stability and a lower rate of difficulty in raising the level of blockade than does 5% lidocaine when administered through microcatheters for continuous subarachnoid anesthesia.

Anesthesia, Spinal↗
PubMed2000

[Isobaric 2% lidocaine in continuous subarachnoid anesthesia using microcatheters].

The objective in the study of the clinical effect of isobaric 2% lidocaine for continuous spinal anesthesia with a microcatheter technique. Nine consecutive patients undergoing lower abdominal surgery under spinal anesthesia were enrolled. We inserted 27 G catheters through 22 G Sprotte (Intralong) needles to administer 20 mg of isobaric 2% lidocaine followed by successive doses of 10 mg until the required level of anesthesia was reached. Repeated injections of 10 mg were given during surgery whenever the level of anesthesia fell as much as one metamere, possibly permitting pain to appear. We recorded hemodynamic variables, level of anesthesia and motor block, as well as complications during and after surgery. The technique was used with nine patients, for whom the mean presurgical dose was 32.3 +/- 9.2 mg and the mean total dose was 51.3 +/- 25.3 mg. However, the protocol for administering the local anesthetic was suspended in three patients due to difficulty in maintaining the achieved level of anesthesia, as repeated injections were required, with consequent patient discomfort. In these patients relatively high levels of blockade were required and surgery lasted longer than one hour. The protocol followed with isobaric 2% lidocaine was not effective for continuous spinal anesthesia with microcatheters because of difficulty of maintaining level of anesthesia.

Aged↗
PubMed2000

[Vancomycin and teicoplanin use as antibiotic prophylaxis in cardiac surgery: pharmacoeconomic study].

BACKGROUND: To assess the economical impact of vancomycin use versus teicoplanin use as antibiotic prophylaxis for patients undergoing cardiac surgery for valve replacement (VR) and coronary artery by-pass (CABS) procedures. PATIENTS AND METHODS: This is an ancillary cost minimization analysis of a double blinded, parallel groups, randomised clinical trial (RCT), with the main objective of comparing the safety and efficacy of these antibiotics. 500 patients were included in the study; 267 in the CABS group and 233 in the VR group. The CABS patients received 1 g vancomicin or 400 mg teicoplanin, plus 150 mg netilmicin. The VR group received a second dose of each drug after extracorporeal circulation. In order to calculate the costs we considered the direct cost of the drug, the i.v. mix and the administration costs, together with personnel and structure costs. We considered two different situations: the administration of drugs within the surgical room theatre and in the medical ward. RESULTS: The demographic data of both groups were comparable. The frequency of severe adverse drug reactions (ADR) were similar (0.4%) in both groups, as well as the post-operative infection rates (8.6%). Differences were seen in the frequencies of low severity ADRs: 20.4% in the vancomycin group and 1.6% in the teicoplanin group. When the antibiotics were administered in the surgical room, among CABS patients the costs were 8,265 pts. for the teicoplanin group and 12,005 pts. for the vancomycin group; while among VR patients, costs were respectively 11,661 pts. and 14,528 pts. Administration costs of teicoplanin and vancomycin within a medical ward setting, however, the costs were 6,740 pts. and 2,809 pts. for CABS patients, and 5,308 pts. and 10,140 pts. for VR patients, respectively. CONCLUSIONS: The costs of antibiotic prophylaxis among cardiac surgery patients heavily depends on the setting and circumstances of drug administration. The minimization cost analysis indicates that teicoplanin is the most cost-effective option if the drug is administered within the surgical area, while vancomycin is the less costly option when administered within the medical ward. However, if the second option is to be chosen, it is necessary to assure the right plasmatic drug levels of the antibiotic at the beginning of the surgical procedure.

Aged↗
PubMed1999

[Predictive factors of hospital admission in ambulatory surgery at a regional hospital].

BACKGROUND: Hospital admission following ambulatory surgery is a valid measure of morbidity and a quality indicator. To improve the efficiency of an ambulatory surgery unit it is essential to study the factors associated with unexpected hospital admission. Our goal was to analyze the association of age, ASA, type of surgical and anesthetic procedures, surgical duration, pain, vomiting and surgical and anesthetic complications with unexpected hospital admission. PATIENTS AND METHODS: Retrospective case-control study. The cases were all patients who underwent ambulatory surgery in the Viladecans Hospital (Barcelona, Spain) from October 1990 till May 1996 (n = 6,071), cases (n1 = 93), controls (n0 = 552). Logistic regression models with a predictive variable and multiple logistic regression were obtained. OR and 95% CI were calculated. RESULTS: Age was not significant for admission. ASA greater than status 1 (OR: 3.4 [1.4-9]); p = 0.01), the procto-perineo-sacrococcygeal procedures have significant risk (OR: 35 [4-304]; p < 0.00001), and other types of surgery were not significant. General, spinal anaesthesia and non-spinal locoregional ones with sedation were not significant (p > 0.2), but spinal anesthesia with deep sedation carried a significant risk (OR: 20 [3-122]; p < 0.00001). Surgical duration higher than 40 min (OR: 22 [5-94]; p < 0.00001), pain (OR: 12 [3-55]; p < 0.00001) and vomiting (OR: 8.5 [1.2-59]; p = 0.03) were significant factors in predicting hospital admission. CONCLUSIONS: The factors related with unexpected hospital admission following ambulatory surgery were: surgical and anesthetic complications, pain, procto-perineal and sacrococcigeal procedures, spinal anesthesia with profound sedation and a surgical duration time higher than 40 min.

Adolescent↗
PubMed1999

Platelet function during cardiac surgery and cardiopulmonary bypass with low-dose aprotinin.

OBJECTIVE: To determine whether two low-dose regimens of aprotinin influence platelet function. DESIGN: Prospective, randomized, single-blinded trial. SETTING: University teaching hospital performing 600 cardiac operations per year. PARTICIPANTS: Fifty-nine patients scheduled for cardiac surgery undergoing cardiopulmonary bypass (CPB) of expected duration of 60 minutes or more. INTERVENTIONS: Patients were randomized into three groups. Group C (control) included 21 patients who did not receive aprotinin. In group A2, 17 patients received 14,286 kallikrein inhibitor units (KIU)/kg (2 mg/kg) of aprotinin before surgery, followed by a continuous infusion of 7,143 KIU/kg/h (1 mg/kg/h) until the end of surgery. In group A4, 19 patients received 28,572 KIU/kg (4 mg/kg) of aprotinin before surgery, followed by the same infusion. MEASUREMENTS AND MAIN RESULTS: Postoperative bleeding and transfusion requirements were significantly less in group A4. Changes in platelet number and function were similar in the three groups. Platelet aggregation was assessed in four periods: before CPB (T1), post-CPB (T2), and 2 hours (T3) and 4 hours (T4) after CPB. Platelet aggregation induced by adenosine diphosphate, 1 and 2 micromol/L; ristocetin, 1 mg/mL; and arachadonic acid (AA), 1.4 mmol/L, decreased at T2 (p < 0.001) in all groups, and for the ristocetin and AA groups, remained at less than baseline values at T3 and T4. In five patients from each group, platelet receptors for glycoprotein IIb-IIIa (GPIIb-IIIa) and expression of platelet activation markers, guanosine monophosphate 140 (GMP-140) and lysosomal protein, were measured by flow cytometry before and after CPB. Modifications in the expression of GPIIb-IIIa were always modest and without statistical significance. Platelet activation markers, GMP-140 or lysosomal protein, nearly doubled from baseline to post-CPB only in the A4 group, whereas they remained stable in both other groups (statistically not significant). CONCLUSION: The two regimens of aprotinin, both considered low dosage, did not exert a protective effect on platelet function. Neither dose produced changes in platelet GPIIb-IIIa or platelet activation markers. However, bleeding and transfusion needs were decreased.

Adenosine Diphosphate↗
PubMed1999

Radicular acute pain after epidural anaesthesia with the technique of loss of resistance with normal saline solution.

Epidural anaesthesia using the loss of resistance to saline technique, without air, was successfully performed in a 65-year-old man scheduled for elective vascular surgery of the right leg. Epidural catheterisation was uneventful. Fifteen minutes after the initial dose of plain 0.5% bupivacaine, the patient experienced severe pain in his lower abdomen and legs which coincided with a supplementary injection of 2 ml bupivacaine and 50 microgram fentanyl, and a change from the lateral to the supine position. General anaesthesia was induced and CT and MRI scans were performed showing trapped air in the epidural space at the L4 level causing compression of the thecal sac. After excluding other causes, the spontaneous entry of air through the Tuohy needle was thought to be the most likely explanation for this complication. The patient recovered uneventfully.

Acute Disease↗
PubMed1999

[Learning cardiopulmonary resuscitation using conventional external cardiac massage or active compression-decompression in simulated cardiopulmonary resuscitation].

OBJECTIVE: To compare medical students' simulated learning of two different techniques of cardiopulmonary resuscitation (CPR). One was conventional external cardiac massage (ECM) and the other was active compression-decompression (ACD-CPR). MATERIAL AND METHODS: The study group (group S) comprised 111 students enrolled in their fourth year of medical studies who had no prior experience of CPR. Group R, the control group, was made up of 32 medical residents in anesthesiology and post-anesthetic intensive care. Before the study, group S received 5 hours of theoretical classes on CPR and both groups saw a video explaining each technique just before performing the test. All subjects applied each method to an adult dummy for one minute. The variables evaluated were frequency of complete and effective thoracic compressions and the body weight of the resuscitator. RESULTS: Each group performed similarly using the two techniques in terms of frequency of total compressions achieved. For each technique, the number of effective compressions achieved by group S (49.4 +/- 22.9 with ECM and 42.5 +/- 20.7 with ACD-CPR) was significantly lower (p < 0.05) than the number attained by group R (71.2 +/- 18.6 with ECM and 58.8 +/- 12 with ACD-CPR). Group R's frequency of effective compressions was significantly higher (p < 0.05) with CPR than with ACD-CPR. Body weight had no influence on the number of total compressions or efficacy in group R, whereas lower body weight in group S was significantly related to lower frequency of effective compressions with ECM p < 0.05). Neither group achieved a frequency of 80 total compressions in one minute. CONCLUSIONS: With the present teaching method, the medical students' performance was poor for both types of CPR and was affected by body weight. The residents' performance was less effective with ACD-CPR, a technique that was new to them, than with conventional ECM, with which they were expert and on which body weight had no impact.

Adult↗
PubMed1999

[Esmolol in anesthesiology: pharmacology and indications].

Esmolol is a beta-adrenergic receptor antagonist with a relatively specific affinity for beta 1 adrenergic receptors. Its mechanism of action is therefore largely cardioselective and only high doses block beta 2 adrenergic receptors. The pharmacologic features of the drug give it rapid onset of beta-blocking action (distribution half-life = 2 minutes) and a short duration of action due to rapid clearance (clearance half-life = 9 minutes). The rapid metabolism of esmolol allows its beta-blocking activity to be lowered rapidly by changing the rate of infusion and obtaining rapid reversibility of effect in the minutes following interruption of the infusion. The esmolol dose is therefore manageable and individual adjustments can be made in function of a patient's clinical status. Such properties mean that esmolol is indicated for short-term treatment of hypertension and tachycardia during the perioperative period and in clinical situations that require easy unblocking of beta receptors. Hypertension and bradycardia are the most frequent complications associated with the administration of esmolol, such that blood pressure, heart rate and electrocardiographic data must be monitored.

Adrenergic beta-Antagonists↗
PubMed1999

[Changes in oxygen saturation in the jugular bulb during cardiac surgery].

OBJECTIVE: Heart surgery with cardiopulmonary bypass (CPB) leads to changes in supply and consumption of cerebral oxygen (DO2 and VO2C). Monitoring jugular bulb oxygen saturation (SjO2) detects changes in the DO2C/VO2C ratio that occur in patients undergoing heart surgery. The objective of this study was to determine the evolution of SjO2, of the arteriovenous difference of cerebral oxygen and of cerebral oxygen extraction, as well as the possible relation between those variables and changes in mean arterial pressure, hemoglobin counts and temperature in patients undergoing heart surgery with CPB. PATIENTS AND METHOD: A prospective study carried out in 31 patients who underwent coronary valve surgery. To monitor SjO2, each patient's internal jugular vein was cannulated with an oximetric catheter in a retrograde direction to monitor SjO2. RESULTS: Baseline SjO2 (68 +/- 7.4%), obtained after anesthetic induction, was similar to SjO2 before (65 +/- 6%) and after (67 +/- 8.2%) CPB. However, SjO2 upon starting CPB (60 +/- 8.6%) and during rewarming (63 +/- 3%) were significantly lower than at baseline. SjO2 was significantly higher during hypothermic bypass (78 +/- 5%) than at baseline. SjO2 ranged from a low of 60 +/- 8% as CPB was initiated to a high of 78 +/- 5% during hypothermic CPB. Mean arterial pressure was significantly lower at the start of bypass (44 +/- 6 mmHg) than anesthetic induction (83.5 +/- 13.1 mmHg) and the decrease correlated with a significant decrease in SjO2. Changes in mean arterial pressure were unrelated to significant changes in SjO2 at other moments, however. Nor was there a significant relation between changes in temperature or hemoglobin and the evolution of SjO2. At least one episode of SjO2 desaturation (= 50%) occurred in 29% of the patients, with the lowest values being recorded at the start of CPB and during rewarming. CONCLUSIONS: The greatest risk of cerebral oxygen imbalance between supply and demand occurs at the start of CPB and during rewarming, as shown by decreases in SjO2 levels below baseline at those times.

Blood Pressure↗
PubMed1998

Postoperative respiratory function in children after abdominal surgery. A comparison of epidural and intramuscular morphine analgesia.

Thirty children undergoing urological and abdominal surgery were entered into a randomised trial comparing the effects of epidural and intramuscular morphine on postoperative respiratory function. The forced vital capacity and the forced expired volume in 1 s were measured before and 6 h after surgery and on each of the following seven days. Significant decreases (p < 0.01) in forced vital capacity and forced expired volume in 1 s were seen after surgery. After the first postoperative day, a gradual recovery in pulmonary function was observed but the measured parameters had not returned to their pre-operative control values by the end of the study. There were no statistically significant differences between the two groups during the study with respect to forced vital capacity and forced expired volume in 1 s. The quality of analgesia was better in the epidural morphine group than in the intramuscular morphine group. The incomplete recovery of pulmonary function suggests that pain is not the only cause of postoperative respiratory changes in these patients.

Abdomen↗
PubMed1998

[Analysis of the current status of neuroanesthesia in Spain using a national survey].

OBJECTIVES: Advances in complementary diagnostic explorations, surgical support technology and the complexity of neurophysiological monitoring require anesthesiologists to acquire specific knowledge for dealing with neurosurgery. We aimed to study the implantation of new anesthetic-surgical techniques in the field of neurosurgery, and the state of neuroanesthesia as a subspecialty in Spain. MATERIAL AND METHODS: A 20-item postal questionnaire sent to anesthesiology department heads of Spanish hospitals with neurosurgery teams. RESULTS: We received responses from 62% of the hospitals surveyed. Of these, 69% performed stereotaxic surgery, 30% functional cerebral surgery (for Parkinson's disease and epilepsy) and 21% offered neuroendoscopy. In 38% of the hospitals cerebral metabolism was monitored (hemoglobin oxygen saturation in the jugular or regional cerebral oxygen saturation) and/or cerebral electrophysiology (electroencephalogram, evoked potentials) and in 23.8% flows and pressures were measured (transcranial precordial and/or tracheoesophageal Doppler). Anesthesiologists specializing in neurosurgery are present in 62% of the hospitals. Interventionist neuroradiology is performed in 57%. It was noteworthy that 14.3% do not regularly have an anesthesiologist present during such high risk procedures. CONCLUSIONS: Although most centers continue performing "classical" neurosurgery with standard monitoring, a substantial proportion of hospitals (38%) show evidence of advancing in anesthetic techniques for neurosurgery in Spain. Anesthesia for neurosurgery as a subspecialty is available in 62% of the responding hospitals.

Anesthesia↗
PubMed1997

[Indication for spinal anesthesia for cesarean section in HELLP syndrome coagulopathy].

We describe the relation between coagulation and local-regional anesthesia in two women with HELLP syndrome who required emergency cesarean delivery. HELLP syndrome involves hemolysis, elevated liver enzyme levels and thrombopenia complicating the hypertension of pregnancy. Regional anesthesia presents advantages for mother and fetus in this context but also involves the risk of coagulopathy. In the first case we describe, coagulation was normal before surgery and epidural anesthesia was therefore prescribed. The initial epidural puncture was hemorrhagic and a second, higher puncture was made to insert the catheter. Shortly after surgery severe thrombopenia developed and lasted 24 hours; formation of an epidural hematoma caused by vascular lesion during puncture was suspected. The epidural catheter was left in place, and the patient was kept under observation and seen by a neurologist within the first 48 hours. Outcome was good. In the second patient, epidural puncture was contraindicated by the presence of preoperative coagulopathy, and the cesarean was performed without complications under intradural anesthesia provided with low doses of bupivacaine and fentanyl. The coagulopathy that accompanies HELLP syndrome should be assessed not only before taking the decision on anesthetic technique; as the condition can be progressive it can become most severe after the epidural puncture is performed, as shown by the first case we describe. The patient's condition must be watched closely until coagulation becomes normal. Removal of the epidural catheter must wait until coagulopathy is resolved. When coagulopathy is evident before surgery, intradural anesthesia is a safe option provided hemodynamic stability is assured, as demonstrated by the second case we report.

Adult↗