PubMed Health⌕ Search

Biomedical subjects

J H Campos

Publications and source records attributed to J H Campos.

14 recordsLinked to original sources
PubMed2001

Lung isolation techniques.

Left-sided double-lumen endotracheal tubes should be the tube of choice for most cases in which lung isolation is required. A right-sided double-lumen endotracheal tube can be used effectively when a contraindication to placing a left-sided double-lumen endotracheal tube exists. The method of choice to select left-sided double-lumen endotracheal tubes is based on chest radiograph or CT scan measurements of the trachea or bronchus. Based on clinical reports, Univents or WEB blockers may be a better choice for patients with difficult airways who require one-lung ventilation or for when a selective lobar blockade is needed. For all selective intubation, the method of choice for proper tube placement and bronchial blockade is fiberoptic bronchoscopy with the patient in a supine position at first or in a lateral decubitus position later, or if a malposition occurs.

Anesthesia↗
PubMed2000

The incidence of right upper-lobe collapse when comparing a right-sided double-lumen tube versus a modified left double-lumen tube for left-sided thoracic surgery.

UNLABELLED: Lung deflation for left-sided thoracic surgery can be accomplished by using either a left- or right-sided double-lumen endotracheal tube (L-DLT or R-DLT). Anatomic variability of the right mainstem bronchus and the possibility of right upper-lobe obstruction have discouraged the routine use of R-DLT. There are, however, situations in which it is preferable to avoid manipulation/intubation of the left main bronchus, requiring placement of a R-DLT. We compared the modified L-DLT with the R-DLT to determine whether R-DLTs can be used during left-sided thoracic surgery without an increased risk of right upper-lobe collapse. Forty patients requiring left lung deflation were randomly assigned to one of two groups. Twenty patients received a modified L-DLT BronchoCath((R)) (Mallinckrodt Medical Inc., St. Louis, MO), and 20 received a R-DLT BronchoCath((R)). The following variables were studied: 1) time required to position each tube until satisfactory placement was achieved; 2) number of times fiberoptic bronchoscopy was required to readjust tube position; 3) number of malpositions after initial tube placement; 4) time required for left lung collapse; 5) incidence of right upper-lobe collapse from an intraoperative chest radiograph obtained in a lateral decubitus position; 6) overall surgical exposure; and 7) tube acquisition cost. Median time required for initial tube placement was greater in the R-DLT group (3.4 min) versus the L-DLT (2.1 min); P = 0.04. Overall tube cost was also larger for the R-DLT group (US $1819.40) versus the L-DLT group (US $1107.75). The incidence of malpositions, (five versus two), need for fiberoptic bronchoscopy, time for adequacy of left lung collapse, and incidence of intraoperative right upper-lobe collapse (0) did not significantly differ between R-DLT and L-DLT groups. We conclude that R-DLTs can be used for left-sided thoracic surgery without an increased risk of right upper-lobe collapse. Our data suggest that R-DLTs may be more prone to intraoperative dislodgment/malposition than L-DLTs; however, in all cases, correction of malposition was easily achieved. IMPLICATIONS: In this study, right-sided double-lumen tubes (R-DLTs) were compared with modified left-sided double-lumen tubes in patients requiring one-lung ventilation for left-sided thoracic surgery. The incidence of right upper-lobe collapse was assessed intraoperatively by a chest radiograph which showed no collapse of the right upper lobe in all patients who received R-DLTs or left-sided double-lumen tubes. Therefore, we conclude that R-DLTs present no increased risk of complications for left-sided thoracic surgery and should not be abandoned.

Adult↗
PubMed1999

A reaction to tape after tracheal extubation in a patient with systemic amyloidosis.

A reaction to tape after tracheal extubation in a patient with systemic amyloidosis is reported. A patient underwent a right thoracotomy with general anesthesia. A double-lumen tube secured with 1-inch adhesive tape (3M Blenderm, 3M Health Care, St Paul, MN) was used. The same kind of tape was used to cover the eyelids. On removal of the tape, hemorrhagic and purpuric lesions appeared on the skin in regions corresponding to the tape contact area. A diagnosis of amyloidosis was made based on large tongue, lip edema, purpuric and hemorrhagic spots on the skin, congestive heart failure, and skin biopsy. Amyloidosis and its anesthetic implications are discussed.

Adhesives↗
PubMed1998

Is there a better right-sided tube for one-lung ventilation? A comparison of the right-sided double-lumen tube with the single-lumen tube with right-sided enclosed bronchial blocker.

UNLABELLED: Anatomic variation between tracheal carina and the take-off of the right upper bronchus often makes the use of a right-sided double-lumen tube (R-DLT) or a single-lumen tube with right-sided enclosed bronchial blocker tube (R-UBB) (Univent) undesirable. This study compared the R-DLT with the R-UBB to determine whether there was any advantage of one over the other during anesthesia with one-lung ventilation (OLV) for right-sided thoracic surgeries. Forty patients requiring right lung deflation were randomly assigned to one of two groups. Twenty patients received a right-sided BronchoCath double-lumen tube, and 20 received a Univent tube with a bronchial blocker placed in the right mainstem bronchus. The following were studied: 1) time required to position each tube until satisfactory placement was achieved; 2) number of times that fiberoptic bronchoscopy was required (including one with the patient supine and one in lateral decubitus position); 3) number of malpositions after initial confirmation of tube placement; 4) time required until lung collapse; 5) surgical exposure; and 6) cost of tubes per case. No differences were found with any of these variables except that the cost of acquisition overall was greater for the R-UBB than for the R-DLT. No right upper lobe collapse was observed in the postoperative period in the chest radiograph in any of the patients studied. We conclude that either tube can be used safely and effectively for right-sided thoracic surgeries that require anesthesia for OLV. IMPLICATIONS: In this study, right-sided double-lumen tubes were compared with the Univent with right-sided bronchial blockers. The results indicate that either tube can be used for right-sided thoracic surgery.

Adult↗
PubMed1997

Effects of oxygenation during selective lobar versus total lung collapse with or without continuous positive airway pressure.

UNLABELLED: Hypoxemia is common during anesthesia with one-lung ventilation (OLV). This study tested the hypothesis that selective lobar blockade would result in higher PaO2 values compared with those found with total lung collapse independent of continuous positive airway pressure (CPAP) application. Thirty patients undergoing lobectomy were randomly assigned to one of four groups with the following maneuvers during OLV: Group 1 (n = 8) total lung collapse (TLC) plus 5 cm H2O of CPAP to the nonventilated operative lung for 15 mins, followed by selective lobe collapse plus 5 cm H2O of CPAP (during selective collapse only the surgical lobe was collapsed and the rest of that lung was ventilated); Group 2 (n = 6) selective lobar collapse plus 5 cm H2O of CPAP to the operative lung, followed by TLC plus 5 cm H2O of CPAP; Group 3 (n = 8) total lung collapse without CPAP, followed by selective lobe collapse and no CPAP; Group 4 (n = 8) selective lobe collapse without CPAP, followed by TLC and no CPAP. To obtain selective lobe collapse, the bronchial blocker of the Univent (Vitaid, Lewiston, NY) endotracheal tube was guided into the operative bronchus with the aid of a fiberoptic bronchoscope. Blood pressure, heart rate, and arterial blood gas measurements were obtained during the following times: Time 1--while the patient was awake; Time 2--two-lung ventilation (2LV) in the supine position; Time 3--after 30 min of OLV in the lateral decubitus position (no CPAP or selective blockade); Time 4 and Time 5--during maneuvers described above (see group description); Time 6--2LV resumed; Time 7--30 min after extubation. Twenty-eight patients completed the study. There were no differences among groups with regard to arterial blood pressure, heart rate, or arterial oxygen saturation during the experimental maneuvers. All four groups showed a decrease in PaO2 from 2LV to OLV (P < 0.05). Both with and without CPAP application, oxygenation was improved with selective lobe collapse compared with TLC. When selective lobe collapse with 5 cm H2O of CPAP followed TLC (group 1), PaO2 values increased to values similar to those found for 2LV (PaO2 449 +/- 122 vs 394 +/- 105 mm Hg). This study indicates that by using a bronchial blocker, changing from total lung collapse to selective lobar blockade improves PaO2 during lung surgery. IMPLICATIONS: This study examines how oxygen tension in arterial blood can be higher during one-lung ventilation. The use of a bronchial blocker, which changes a total lung collapse to selective lobar blockade, improves oxygenation during lung surgery.

Adult↗
PubMed1996

Comparison of a modified double-lumen endotracheal tube with a single-lumen tube with enclosed bronchial blocker.

This study compared the modified BronchoCath double-lumen endotracheal tube with the Univent bronchial blocker to determine whether there were objective advantages of one over the other during anesthesia with one-lung ventilation (OLV). Forty patients having either thoracic or esophageal procedures were randomly assigned to one of two groups. Twenty patients received a left-side modified BronchoCath double-lumen tube (DLT), and 20 received a Univent tube with a bronchial blocker. The following were studied: 1) time required to position each tube until satisfactory placement was achieved; 2) number of times that the fiberoptic bronchoscope was required; 3) frequency of malpositions after initial placement with fiberoptic bronchoscopy; 4) time required until lung collapse; 5) surgical exposure ranked by surgeons blinded to type of tube used; and 6) cost of tubes per case. No differences were found in: 1) time required to position each tube (DLT 6.2 +/- 3.1 versus Univent 5.4 +/- 4.5 min [mean +/- SD]); 2) number of bronchoscopies per patient (DLT median 2, range 1-3 versus Univent median 3, range 2-5); or 3) time to lung collapse (DLT 7.1 +/- 5.4 versus Univent 12.3 +/- 10.5 min). The frequency of malposition was significantly lower for the DLT (5) compared to the Univent (15) (P < 0.003). Blinded evaluations by surgeons indicated that 18/20 DLT provided excellent exposure compared to 15/20 for the Univent group (P = not significant). We conclude that in spite of the greater frequency of malposition seen with the Univent, once position was corrected adequate surgical exposure was provided. In the Univent group the incidence of malposition and cost involved were both sufficiently greater that we cannot find cost/ efficacy justification for routine use of this device.

Adult↗
PubMed1986

Combined effects of verapamil and isoflurane on coronary blood flow and myocardial metabolism in the dog.

The effects of three different plasma levels of verapamil on coronary hemodynamics and myocardial metabolism in the presence of 1.61 +/- 0.05% end-tidal concentration of isoflurane (mean +/- SEM) were studied in a canine model, using a thermodilution coronary sinus catheter to measure coronary sinus blood flow and pressure and to provide coronary sinus plasma samples. A control group receiving only isoflurane was also studied (n = 6). Plasma arterial verapamil levels of 55 +/- 7 (n = 6); 134 +/- 7 (n = 10); and 301 +/- 37 ng X ml-1 (n = 5), were achieved by a loading dose followed by a continuous infusion for 30 min. The only changes with time in the isoflurane group were decreases in left ventricular maximum rate of tension development (dP/dt) and left ventricular stroke work index compared with control after 90 min without changes in myocardial oxygen balance. The low plasma verapamil level caused reductions in heart rate, mean and diastolic arterial pressure, and left ventricular dP/dt without changes in myocardial oxygen supply or myocardial metabolism. Intermediate verapamil concentrations produced a transient initial increase in heart rate and a reduction in stroke volume index. With the intermediate and the highest levels of verapamil, mean and diastolic arterial pressure, left ventricular dP/dt, and cardiac index were decreased. An increase in arterial norepinephrine plasma levels was seen in the intermediate and the highest levels of verapamil; however, a transient coronary vasodilation occurred without changes in myocardial oxygen balance. Significant prolongation of the PR interval was observed in all verapamil groups, with second or third degree heart block in some of the higher-dose animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Plasma diltiazem levels, cardiovascular function, and coronary hemodynamics during enflurane anesthesia in the dog.

Diltiazem was administered to dogs by an intravenous infusion protocol, which resulted in plasma levels of 71 +/- 6 (n = 7), 139 +/- 9 (n = 7), 353 +/- 33 (n = 10), and 1064 +/- 143 (n = 6) ng/ml, to evaluate the effects of diltiazem on cardiovascular function and coronary hemodynamics in the presence of anesthetic concentrations of enflurane. An additional group of six dogs received enflurane only. The only changes observed with enflurane alone were a decrease in left ventricular (LV) dP/dt, cardiac index (CI), and coronary blood flow 60 min after the baseline measurements were made. In all of the diltiazem groups, plasma level-related prolongation of the PR interval of the electrocardiogram was observed, with development of second degree heart block and junctional rhythms in animals at the two higher plasma levels. Mean arterial pressure and LV dP/dt decreased at the two higher diltiazem plasma levels after 30 min of infusion, and three of six dogs in the highest group had to be dropped from the study because of severe hypotension. The cardiac index was no different from enflurane alone with the three lower plasma diltiazem levels. No changes were observed in coronary sinus blood flow, coronary vascular resistance, myocardial oxygen uptake, or myocardial lactate extraction. Circulating norepinephrine levels were elevated in the two higher diltiazem groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗
PubMed1986

Influence of diltiazem on cardiovascular function and coronary hemodynamics during isoflurane anesthesia in the dog: correlation with plasma diltiazem levels.

Diltiazem was administered to dogs by intravenous infusion to achieve plasma levels of 47 +/- 3 (n = 7), 148 +/- 12 (n = 8), 263 +/- 10 (n = 8), and 379 +/- 43 (n = 8) ng X ml-1, to evaluate the effects of diltiazem on cardiovascular function and coronary hemodynamics, when given in the presence of anesthetic concentrations of isoflurane. Plasma level related prolongation of the PR interval of the electrocardiogram was the most prominent effect observed, with development of 2 degrees heart block or junctional rhythms in several of the animals at the two higher plasma levels. Mean arterial pressure, transiently decreased after the loading dose in all groups, was no different from control values after 30 min of infusion. Left ventricular dP/dt was mildly decreased at the three highest plasma levels, whereas right and left heart filling pressures were increased at the two highest plasma levels. Cardiac index and systemic vascular resistance were unchanged. No changes were observed in coronary sinus blood flow, coronary vascular resistance, myocardial oxygen uptake, myocardial lactate extraction, or circulating epinephrine or norepinephrine levels in any of the groups. In the presence of anesthetic concentrations of isoflurane, over the range of plasma levels investigated in this study, the vasodilating properties of diltiazem were not observed, yet conduction effects were prominent and decreases in left ventricular performance occurred. No untoward effects on global myocardial metabolism were detected under these conditions.

Anesthesia↗
PubMedDate not supplied

Visceral leishmaniasis in Teresina, State of Piauí, Brazil: preliminary observations on the detection and transmissibility of canine and sandfly infections.

A Leishmania donovani-complex specific DNA probe was used to confirm the widespread dissemination of amastigotes in apparently normal skin of dogs with canine visceral leishmaniasis. When Lutzomyia longipalpis were fed on abnormal skin of five naturally infected dogs 57 of 163 (35%) flies became infected: four of 65 flies (6%) became infected when fed on apparently normal skin. The bite of a single sandfly that had fed seven days previously on a naturally infected dog transmitted the infection to a young dog from a non-endemic area. Within 22 days a lesion had developed at the site of the infective bite (inner ear): 98 days after infection organisms had not disseminated throughout the skin, bone marrow, spleen or liver and the animal was still serologically negative by indirect immunofluorescence and dot-enzyme-linked immunosorbent assay. When fed Lu. longipalpis were captured from a kennel with a sick dog known to be infected, 33 out of 49 (67%) of flies contained promastigotes. In contrast only two infections were detected among more than 200 sandflies captured in houses. These observations confirm the ease of transmissibility of L. chagasi from dog to sandfly to dog in Teresina. It is likely that canine VL is the major source of human VL by the transmission route dog-sandfly-human. The Lmet2 DNA probe was a useful epidemiological tool for detecting L. chagasi in sandflies.

Animals↗
PubMedDate not supplied

Preliminary observations on the diagnosis and transmissibility of canine visceral leishmaniasis in Teresina, n.e. Brazil.

A pilot group of 49 dogs and control groups from non-endemic areas were examined serologically for the presence of visceral leishmaniasis (VL) by direct agglutination test (DAT), indirect immunofluorescence (IFAT) enzyme-linked immunosorbent assay (ELISA) and DOT-ELISA. Results indicated that DAT is less sensitive than the other assays and that serology with filter paper blood samples is less sensitive than with serum. Promastigote infections were common in fed Lutzomyia longipalpis taken from a dog kennel inhabited by a dog carrying Leishmania chagasi. Colony-bred Lu. longipalpis readily acquired L. chagasi infection when fed on skin lesions of dogs naturally infected with L. chagasi: a small proportion of flies also became infected when fed on apparently normal skin. Widespread distribution of amastigotes in normal skin of asymptomatic animals was shown both by intensive microscopy and by probing skin biopsy samples with the Lmet2 L. donovani-complex specific DNA probe. It was demonstrated that an immunologically naive dog could be infected by a single experimentally infected sand fly. Abundant amastigotes present within the resultant lesion 22 days later were transmissible to sand flies but serology remained negative at least 45 days after the infective bite. Experimental transmission of canine VL by sand fly bite is a valuable approach for determining which diagnostic procedures are most sensitive, specific and suitable for field application in suburban households.

Agglutination Tests↗