Assessment of cardiac function in patients who were morbidly obese

Cardiac function of 30 patients who were morbidly obese was studied before bariatric surgery. Twelve patients were studied 13 +/- 4 months after surgery. These patients had a mean age of 37.1 +/- 2.9 years and a body mass index of 50.0 +/- 1.4 kg/m2. Cardiac function was measured by echocardiography, radionuclide angiography scanning, and right heart catheterization. To determine the degree of cardiac dysfunction, the patients were studied with exercise and intravenous fluid challenges. Ultrasonography produced evidence of myocardial thickening with an increased interventricular septum in eight patients (32%) and increased left ventricular mass in 17 patients (53%). The radionuclide scan suggested that morbid obesity was associated with a significantly (p less than 0.05) increased end-diastolic volume and decreased left ventricular ejection fraction as compared with patients who were of normal weight. With exercise the patient who was of normal weight had an increase in the end-diastolic volume, stroke volume, and heart rate, but the patient who was morbidly obese only increased heart rate to produce the necessary increase in cardiac output. Right heart catheterization indicated that the relationship of the pulmonary wedge pressure and the left ventricular stroke work index was abnormal in 14 of 29 patients (48.3%) and depressed in six of 29 patients (20.7%) with exercise. One liter of fluid caused an abnormal relationship of the pulmonary wedge pressure and the left ventricular stroke work index in 12 of 30 patients (40%) and a depressed response in 10 of 30 patients (33.3%). Cardiac studies were repeated in 12 patients after a 54.8 +/- 1.9 kg weight loss. Echocardiography indicated a decrease in dilatation (27.3% to 9.1%) and a significant (p less than 0.05) decrease in hypertrophy (45.5% to 0%). After the weight loss, radionuclide and right heart catheterization studies indicated improved cardiac function with reduced filling pressures and increased left ventricular work during fluid and exercise challenges. These results support the presence of obesity-related cardiomyopathy with ventricular dysfunction, which appears to be caused by a noncompliant ventricle. Significant weight loss achieved with gastroplasty results in increased ventricular compliance and improved cardiac function.     

Renal function and cardiopulmonary bypass in pediatric cardiac surgical patients

We studied prospectively the perioperative changes of renal function in nine children undergoing cardiac surgery with cardiopulmonary bypass (CPB). Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured with inulin and ¹³¹I-hippuran clearances before CPB, during hypo and normothermic CPB, following sternal closure and 1 h postoperatively. Urinary alpha glutathione S-transferase (alpha GS-T) was measured pre- and postoperatively as a marker for tubular cellular damage. Plasma and urine creatinine and electrolytes were measured. Free water, osmolal and creatinine clearances, as well as fractional excretion of sodium (FeNa) and potassium transtubular gradient (TTKG) were calculated. GFR was normal before and after surgery. ERPF was low before and after surgery; it increased significantly immediately after CPB. Filtration fraction (FF) was abnormally elevated before and after surgery; however, a significant decrease during normothermic CPB and sternal closure was found. Alpha GS-T presented a moderate, but nonsignificant increase postoperatively. FeNa also increased in this period, but not significantly. Creatinine, osmolal, free water clearances, as well as TTKG, were normal in all patients pre- and postoperatively. We conclude that there is no evidence of clinically significant deterioration of renal function in children undergoing repair of cardiac lesions under CPB. Minor increases of alpha GS-T in urine postoperatively did not confirm cellular tubular damage. There was no tubular dysfunction at that time.Supported by grant 1030645 from FONDECYT.     

Post-operative pressure lability and cardiac baroreflex in normotensive patients as a function of age

Background: Pressure lability may be linked to the loss of the cardiac baroreflex. The reduction of the sensitivity of the cardiac baroreflex has not been delineated in the post‐operative period according to age in normotensive patients. This study addresses pressure lability and slope of the cardiac baroreflex as a function of age. Methods: Patients were allocated to the following three groups: young (20–39 years, n=7), middle aged (40–59 years, n=7) and elderly (60–79 years, n=6), and studied before minor intra‐abdominal surgery under CO₂ peritoneal insufflation and nitrous oxide–isoflurane–sufentanil anesthesia, up to 24 h after extubation. An electrocardiogram and non‐invasive beat‐by‐beat pressure monitoring (Finapres^®) allowed offline calculation of the sensitivity of the cardiac baroreflex (‘sequence’ technique) and standard deviation (SD) of heart rate (HR; HR variability) and systolic blood pressure (SBP; pressure lability). Results: Before anesthesia, (a) an inverse relationship was observed between the slope of the cardiac baroreflex and age and (b) a trend (P<0.09) existed between the slope of the cardiac baroreflex and pressure lability, irrespective of age. During the early post‐operative period, young patients returned to their baseline slope of the cardiac baroreflex; no inverse relationship between increased SD of SBP and decreased SD of RR interval was observed. Middle‐aged and elderly patients displayed a depressed slope of the cardiac baroreflex both before and after anesthesia. Conclusion: At variance with the pre‐operative period, no simple inverse relationship was observed between increased pressure lability and depressed HR variability in young patients during the early post‐operative period.     

Effects of L-arginine and L-NAME on the renal function in hypertensive and normotensive subjects

BACKGROUND/AIM: Renal vasodilation in response to L-arginine has been reported to be diminished in hypertensive (HT) subjects. If this diminished renal vasodilator response indicates disturbance of the renal NO pathway, a diminished renal vasoconstrictor response to NO synthase inhibition may be present in HT subjects as well. The present study was conducted to compare the effects of L-arginine and N(G)-nitro-L-arginine methyl ester (L-NAME) on renal and systemic hemodynamics between HT and normotensive (NT) subjects. METHODS: The responses of renal and systemic vascular resistances (RVR and SVR) and plasma noradrenaline and renin (NOR and PRA) to systemic NO stimulation and inhibition were studied in patients with grade 1 essential HT and age- and sex-matched NT subjects. On separate occasions, after baseline values were obtained, 40-min randomly administered intravenous infusions of L-arginine (12.5 mg.kg(-1).min(-1)) or L-NAME (0.0125 mg.kg(-1).min(-1)) were given. RESULTS: Baseline values of RVR (129 +/- 21 and 162 +/- 10 resistance units) and SVR (15.1 +/- 4.3 and 21.6 +/- 5.1 resistance units) were higher (p < 0.01) in HT than in NT subjects, whereas the baseline values of NOR and PRA were similar. Infusion of L-arginine caused similar decrements in SVR (29 +/- 10 and 31 +/- 11%), but the decrease in RVR was smaller (22 +/- 8 and 35 +/- 12%, respectively; p < 0.05) in HT than in NT subjects. In response to L-NAME, the increments in RVR (66 +/- 10 and 61 +/- 25%) and SVR (36 +/- 21 and 34 +/- 18%) were similar in HT and NT subjects. In both groups, infusion of L-arginine was associated with similar increments, whereas infusion of L-NAME was associated with similar decrements in NOR and PRA. CONCLUSIONS: This study confirms the smaller renal vasodilator response to L-arginine in HT than in NT subjects. Whether this is caused by a disturbance of the renal NO pathway remains doubtful considering the observed similar L-NAME-induced increments in RVR and SVR in the two groups of subjects.     

Variability of plasma aprotinin concentrations in pediatric patients undergoing cardiac surgery

OBJECTIVES: Infants and children undergoing cardiopulmonary bypass for repair of congenital heart defects are at substantial risk for excessive bleeding, contributing greatly to morbidity and mortality. Aprotinin significantly reduces bleeding and transfusion requirements in adults but is of indeterminate value for pediatric patients. The aim of this study was to determine plasma aprotinin concentrations in these patients with a functional aprotinin assay. METHODS: Thirty patients less than 16 years of age scheduled for cardiac surgery with aprotinin were enrolled. Aprotinin was administered as a 25,000 KIU/kg bolus, 35,000 KIU/kg cardiopulmonary bypass prime, and 12,500 KIU.kg(-1).h(-1) continuous infusion. Blood samples for aprotinin concentrations (kallikrein-inhibiting units/milliliter) were obtained before aprotinin; 5 minutes post-bolus; 5 minutes after cardiopulmonary bypass initiation; 30 and 60 minutes on cardiopulmonary bypass; on discontinuation of aprotinin; 1 hour after aprotinin discontinuation; and 4 hours after permanent separation from cardiopulmonary bypass. For analysis, patients were grouped according to weight (<10 kg, 10-20 kg, >20 kg). Differences between weight groups were assessed using an exact test for categoric variables and 1-way analysis of variance for continuous variables. RESULTS: Aprotinin concentrations differed significantly across weight groups. Five minutes after aprotinin bolus and initiation of cardiopulmonary bypass, there was significant correlation between weight and aprotinin concentration (r =.57, P =.003; r =.69, P =.001, respectively). CONCLUSION: A functional assay reveals significant variability in aprotinin concentration for pediatric patients using current weight-based aprotinin dosing. Additional investigation is necessary to determine target aprotinin concentration dosing regimens to provide better efficacy.     

Effect of dexmedetomidine on hemodynamics in pediatric patients following cardiac surgery

BACKGROUND: Dexmedetomidine (DEX), a highly selective alpha2-adrenergic receptor agonist, has sedative and analgesic properties with minimal respiratory depression. We retrospectively evaluated the hemodynamic effects of dexmedetomidine in pediatric patients following cardiac surgery. METHODS: The subjects were twenty children aged 4 months to 15 years who had undergone cardiac surgery. After hemodynamics were stabilized in ICU, DEX was infused at a rate of 0.3-0.5 microg x kg(-1) min(-1), following initial loading (0.5 microg x kg(-1) over 10 min). Heart rate and blood pressure were analyzed just before starting infusion, following 1, 3, 6 hours during infusion, and at the end of the infusion. RESULTS: There was no change in blood pressure during measurement. HR was slightly decreased during DEX infusion but not significantly. After discontinuation of DEX, HR was significantly increased from 109 +/- 17 to 124 +/- 19 beats x min(-1) (mean +/- SD) (P < 0.05). Two patients were excluded from the study, because clinically significant bradycardia developed during DEX infusion. CONCLUSIONS: DEX had little effect on blood pressure in patients after cardiac surgery. DEX, however, had a tendency to decrease HR. Therefore, it shoud be used with caution in patients with low heart rate.     

Effect of Vitamins D<Subscript>2</Subscript> and D<Subscript>3</Subscript> Supplement Use on Serum 25OHD Concentration in Elderly Women in Summer and Winter

Vitamin D₂ and D₃ are generally considered equipotent in humans. A few studies have reported that serum 25OHD levels are higher in vitamin D₃- compared with vitamin D₂-supplemented subjects. As both vitamin D₂ and D₃ supplements are commonly used by elderly in United States, in the present study we determined the effect of self-reported vitamin D₂ and vitamin D₃ supplement use on serum total 25OHD levels according to season in elderly women aged 65–77 years. Serum total 25OHD levels were determined in winter and summer in unsupplemented women (N = 307) and in women who reported taking vitamin D₂ (N = 56) and vitamin D₃ (N = 55) supplements by competitive protein binding assay. In vitamin D₂-supplemented women, the contribution of vitamin D₂ and D₃ to the mean serum total 25OHD level was assessed by HPLC. In summer, there were no significant differences in the mean total serum 25OHD levels (ng/ml) among the vitamin D₂ (32 ± 2.1), vitamin D₃ (36.7 ± 1.95), and unsupplemented (32.2 ± 0.95) groups. In winter, the mean serum total 25OHD levels were higher in women on vitamin D₂ (33.6 ± 2.34, P < 0.05) and vitamin D₃ (29.7 ± 1.76, NS) supplements compared with unsupplemented women (27.3 ± 0.72). In vitamin D₂-supplemented women, about 25% of the mean serum total 25OHD was 25OHD₂, in both summer and winter. Twelve percent of unsupplemented women and 3.6% of vitamin D-supplemented women had a mean serum total 25OHD level below 15 ng/ml in winter. In elderly subjects, both vitamin D₂ and Vitamin D₃ supplements may contribute equally to circulating 25OHD levels, with the role of vitamin D supplement use being more predominant during winter. This work was presented in part as an abstract at Second Joint Meeting of the American Society for Bone and Mineral Research and The International Bone and Mineral Society, San Francisco, CA, 1–6 December 1998.     

Effect of erythropoietin on hematocrit and blood pressure in normotensive and hypertensive rats.

Treatment with recombinant human erythropoietin (rHuEPO) successfully reverses anemia in uremic patients. Of major concern, however, are blood pressure (BP) increases during rHuEPO therapy, observed particularly in persons with a history of hypertension. To determine whether preexisting hypertension enhances BP increases to rHuEPO, BP responses to 2 wk of rHuEPO or placebo were observed in spontaneously hypertensive rats (SHR) and their normotensive genetic controls (Wistar-Kyoto [WKY] rats. In addition, the role of endothelial-released nitric oxide (NO) in BP alterations caused by rHuEPO through i.v. infusions of endothelium-dependent and independent vasoactive agents were indirectly examined. At trial completion, rHuEPO elevated hematocrit, hemoglobin, and mean cell volume more in SHR than in WKY rats (P less than 0.001). Despite the considerable increase in hematocrit, rHuEPO did not alter BP in either strain. An infusion of NG-monomethyl-L-arginine (L-NMMA), a specific inhibitor of NO formation, elevated BP more in rHuEPO-treated SHR than in identically treated WKY rats (P less than 0.05). Further, the administration of L-arginine caused a greater decrease in blood pressure in SHR than in WKY rats, independent of treatment condition (P less than 0.01). Because changes in BP with endothelium-independent agents were similar across groups, responses to L-NMMA and L-arginine were specific to the endothelium and probably independent of basal BP. Thus, rHuEPO provoked greater erythropoiesis in SHR than in WKY rats but did not elevate BP. L-NMMA stimulated higher BP in SHR treated with rHuEPO, suggesting a compensatory increase in vasodilatory NO synthesis to protect against a hypertensive effect of the drug in SHR.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of sirolimus on renal ischaemia/reperfusion injury in normotensive and hypertensive rats

Background. Renal ischaemia/reperfusion (I/R) injury and hypertension represent major alloantigen-independent factors contributing to the development of chronic allograft nephropathy of renal allografts. In the present study, we investigated the effect of the anti-proliferative immunosuppressant, sirolimus (SIR), in a model of accelerated renal injury in hypertensive transgenic rats (TGRs). Twenty anaesthetized uninephrectomized TGRs with renin overproduction [TGR(mREN2)27] and 20 normotensive Han SD (SD) rats as genetic controls had their renal pedicles clipped for 45 min and were subsequently treated with either SIR (0.5 mg/kg per day, orally) or placebo (n=10 in each group) for 16 weeks, after which time the kidneys were harvested for morphological and immunohistochemical analysis. High-renin hypertension aggravated the functional and structural changes induced by I/R in SD animals: both SIR-treated and untreated TGRs exhibited significantly greater proteinuria and suffered from more severe glomerulosclerosis (P<0.01) and vasculopathy (P<0.01), as well as compensatory renal hypertrophy (P<0.01) and tissue TGF-1 expression, than both normotensive SD groups (P<0.01). SIR-treated SD rats showed reduced proteinuria (P<0.01), glomerulosclerosis (P<0.01), and TGF-1 expression in the glomerular epithelium and proximal tubuli (P<0.05) compared with placebo-treated SD rats. SIR-treated TGRs had significantly lower proteinuria at week 4 after I/R (P<0.01) than placebo-treated TGRs, but there were no significant differences thereafter. Morphological patterns were similar in treated and untreated TGRs at week 16. High-renin-induced hypertension aggravated the renal injury induced by I/R. Sirolimus treatment ameliorated some late functional and morphological changes induced by I/R injury in hypertensive TGRs but, particularly, in normotensive SD rats.     

The effects of Brescia-Cimino fistulas and cardiac function in transplanted pediatric patients.

The cardiac hemodynamic effects of patent Brescia Cimino fistulas were assessed using non-invasive techniques in 10 pediatric patients who had undergone successful renal cadaveric transplantation. All had hemoglobin levels above 11 g/dl and had serum creatinine values of less than 1.5 mg/dl. Studies were done prior to and after temporary fistula occlusion to assess the effect of fistula patency on parameters of cardiac function. Values obtained prior to fistula occlusion were compared to those obtained in a normal control population. It was noted that though fistula patency did significantly alter cardiac function, changes were such that fistula patency could be safely maintained. It was also noted that the difference in cardiac index prior to and after occlusion provided a good assessment of fistula flow.     

Effects of anesthesia on plasma and kidney ANG II levels in normotensive and ANG II-dependent hypertensive rats

BACKGROUND: Previous studies have implicated that normotensive rats with normal renal renin activity respond to anesthesia and surgery with greater increases in plasma and kidney angiotensin II (ANG II) concentrations than ANG II-dependent hypertensive rats with intrarenal renin depletion. In the present study, we therefore compared plasma and kidney ANG II levels in anesthetized and conscious normotensive and ANG II-dependent hypertensive rats. METHODS: Salt-replete Hannover-Sprague-Dawley rats (HanSD) served as controls. As models of ANG II-dependent hypertension we used: 1st, transgenic rats harboring the Ren-2 renin gene (TGR); 2nd, two-kidney, one-clip (2K1C) Goldblatt hypertensive rats, and, 3rd, ANG II-infused hypertensive rats. As additional model with enhanced renin-angiotensin system (RAS) activity, salt-depleted HanSD and TGR were employed. RESULTS: In anesthetized salt-repleted HanSD, plasma and kidney ANG II levels were higher than in salt-repleted TGR, ANG II-infused and 2K1C rats. Salt depletion caused marked increases in ANG II levels in HanSD but did not alter them in TGR. In contrast, in conscious animals immediately after decapitation plasma and kidney ANG II levels were similar in salt-repleted and salt-depleted TGR, in ANG II-infused rats, in the clipped kidney of 2K1C rats and in salt-depleted HanSD and in all these groups they were significantly higher than in salt-repleted HanSD. CONCLUSIONS: These findings indicate that anesthesia increases plasma and kidney ANG II levels in HanSD to a greater degree than in ANG II-dependent models of hypertension. Therefore, the results from studies employing anesthetized animals must be interpreted with caution.     

Association between left ventricular mass index and cardiac function in pediatric dialysis patients

Background  

Left ventricular mass index (LVMI) is a surrogate of left ventricular hypertrophy and a predictor of cardiac morbidity and mortality in adults with hypertension. LVMI has not been linked to cardiovascular endpoints in children. The aim of this study was to identify an association between elevated LVMI and echocardiographic markers of systolic and diastolic function.     

Bariatric surgery improves cardiac function in morbidly obese patients with severe cardiomyopathy.

BACKGROUND: Longstanding morbid obesity can be associated with severe cardiomyopathy. However, the safety and efficacy of bariatric surgery in patients with severe cardiomyopathy has not been studied, and the effect of surgical weight loss on postoperative cardiac function is also unknown. In addition, morbidly obese patients have significantly increased mortality associated with cardiac transplantation, often precluding them from becoming recipients. METHODS: A retrospective study of patients with a left ventricular ejection fraction < or =35% who underwent bariatric surgery (1998-2005) was performed. Short-term morbidity/mortality, length of stay, excess weight loss, pre- and postoperative left ventricular ejection fraction, and New York Heart Association (NYHA) functional class were assessed. RESULTS: A total of 14 patients (10 men and 4 women) with a mean preoperative body mass index of 50.8 +/- 2.04 kg/m(2) underwent bariatric surgery (10 underwent laparoscopic Roux-en-Y gastric bypass, 1 open Roux-en-Y gastric bypass, 2 sleeve gastrectomy, and 1 laparoscopic gastric banding). The complications were pulmonary edema in 1, hypotension in 1, and transient renal insufficiency in 2. The median length of stay was 3.0 days (range 2-9). The mean excess weight loss at 6 months was 50.4%, with a decrease in the mean body mass index from 50.8 +/- 2.04 kg/m(2) to 36.8 +/- 1.72 kg/m(2). The mean left ventricular ejection fraction at 6 months had significantly improved from 23% +/- 2% to 32% +/- 4% (P = .04), correlating with improved functional capacity, as measured by the NYHA classification. Preoperatively, 2 patients (14%) had an NYHA classification of IV, 6 (43%) a classification of III, and 6 (43%) a classification of II. At 6 months postoperatively, no patient had an NYHA classification of IV, 2 (14%) had a classification of III, and 12 (86%) an NYHA classification of II. Two patients had undergone cardiac transplant evaluations preoperatively and underwent successful transplantation after weight loss. CONCLUSION: The results of our study have shown that bariatric surgery for patients with cardiomyopathy is feasible and effective. Surgically induced weight loss results in both subjective and objective improvement in cardiac function. In addition, surgical weight loss can provide a bridge to transplantation in patients who were prohibited secondary to their morbid obesity.     

Serum neutrophil gelatinase-associated lipocalin as a marker of renal function in hypertensive and normotensive patients with coronary artery disease

Aim: Hypertension is one of the risk factors for cardiovascular diseases. The kidneys could be a victim and/or culprit of hypertension. Recently, the value of neutrophil gelatinase‐associated lipocalin (NGAL) was highlighted as a novel marker for early detection of acute renal damage. Therefore, the aim of the study was to assess whether hypertension could affect NGAL and cystatin C levels in patients with normal serum creatinine (lower than 1.5 mg/dL in males and 1.2 mg/dL in females) and stable coronary artery disease. Methods: Serum, urinary NGAL, cystatin C and estimated glomerular filtration rate (eGFR; Modification of Diet in Renal Disease study (MDRD) and Cockcroft–Gault formulas) were evaluated in hypertensive, normotensive patients with stable coronary heart disease and healthy volunteers. Results: Normotensives had significantly lower NGAL than hypertensives. Serum cystatin C was significantly lower in normotensives than in hypertensives. Urinary NGAL did not differ significantly between these groups. Despite similar serum creatinine levels, eGFR (MDRD and Cockcroft–Gault formulas) was significantly higher in normotensives than in hypertensives. Serum NGAL was related, in univariate analysis, to serum creatinine, urea, urinary NGAL, haemoglobin, haematocrit, duration of hypertension, age, eGFR by MDRD and Cockcroft–Gault, and cystatin C. Conclusion: Hypertension is associated with kidney injury as reflected by elevated serum NGAL and cystatin C. It is noteworthy that despite normal serum creatinine, eGFR is relatively low suggesting impaired renal function. Therefore, NGAL needs to be investigated as a potential early marker for impaired kidney function/kidney injury, especially in patients with another risk factor for kidney damage, namely coronary artery disease.     

Proteinuria in cubilin-deficient patients with selective vitamin B<Subscript>12</Subscript> malabsorption

Selective vitamin B(12) malabsorption or Gr?sbeck-Imerslund disease (megaloblastic anemia 1) is frequently accompanied by proteinuria. The malabsorption-proteinuric syndrome of Finnish patients is caused by a defect in the multiligand receptor cubilin. We studied the urinary proteins of control subjects and 13 adult patients with three defined cubilin mutations (FM1, FM2, FM3), all diagnosed during childhood and subsequently observed. The overall kidney function was unimpaired and did not deteriorate with time. The excretion of total protein and albumin, and to lesser extent of transferrin, immunoglobulin light chains, and alpha(1)- and beta(2)-microglobulins, was clearly elevated in 3 patients, mildly elevated in 3, and hardly or not at all increased in the rest. The urinary cobalamin-intrinsic factor receptor was low in 5 patients studied and lowest in the group with clear-cut proteinuria. The proteinuria was not of the classical glomerular or tubular type, but apparently due to the lack of cubilin function needed for tubular reabsorption of some, but not all, proteins of the primary urine.     

Effects of nicardipine on the circulatory responses to tracheal intubation in normotensive and hypertensive patients

This study was undertaken to examine the effects of nicardipine on circulatory responses to laryngoscopy and tracheal intubation in normotensive (n = 39) and hypertensive (n = 36) patients. Laryngoscopy and tracheal intubation were performed after induction of anaesthesia with thiamylal, followed by administration of intravenous saline or nicardipine 20 or 30 micrograms.kg-1 and suxamethonium. Blood pressure and heart rate were recorded, and rate-pressure product was calculated. Nicardipine 20 and 30 micrograms.kg-1 prevented the increase in mean arterial pressure after intubation in normotensive and hypertensive patients (p less than 0.01 compared with saline). The changes in heart rate after intubation were significantly greater in normotensive patients than in hypertensive patients when 20 or 30 micrograms.kg-1 of nicardipine was given (p less than 0.05 and p less than 0.01 respectively). Rate-pressure product increased significantly (p less than 0.01) after intubation in normotensive patients whether nicardipine was administered or not, but the increase was suppressed completely by nicardipine 20 or 30 micrograms.kg-1 in hypertensive patients. We conclude that nicardipine is effective in preventing the circulatory responses to laryngoscopy and tracheal intubation in hypertensive patients.     

Hemodynamic responses among three tracheal intubation devices in normotensive and hypertensive patients

We compare hemodynamic responses in normotensive and hypertensive anesthetized paralyzed patients among three intubation devices: the Macintosh laryngoscope (LS), the Trachlight lightwand (LW), and the intubating laryngeal mask airway Fastrach (ILM). Seventy-five normotensive and 75 hypertensive patients were randomly assigned to each intubation device (n = 25). Noninvasive systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were recorded immediately preinduction, immediately preintubation, and every minute for the first 5 min after the successful intubation. The number of intubation attempts, the time to successful intubation, and any airway injuries were recorded. Pharyngolaryngeal morbidity was assessed 18-24 h after surgery by a blinded investigator. In all groups, there was a reduction in SBP and DBP but no change in HR immediately preintubation compared with baseline values. In all groups, HR increased, but there were no increases in SBP and DBP other than in DBP in the LS/hypertensive group after intubation compared with baseline values. In normotensive patients, there were no differences in any hemodynamic variables among the three devices. In hypertensive patients, SBP and DBP in the LS group were significantly higher than the ILM and LW groups for 2 min after intubation, but there were no differences in HR among the devices. The number of intubation attempts was similar among groups, but intubation time was longer for the ILM group. The incidence of airway injury was more frequent for the ILM than the LS and LW groups (16% versus 0% versus 0%). There were no differences in pharyngolaryngeal morbidity among groups. We conclude that both the ILM and the LW attenuated the hemodynamic stress response to tracheal intubation compared with the LS in hypertensive, but not in normotensive, anesthetized paralyzed patients. IMPLICATIONS: Both the intubating laryngeal mask airway Fastrach and the Trachlight lightwand attenuate the hemodynamic stress response to tracheal intubation compared with the Macintosh laryngoscope in hypertensive, but not in normotensive, anesthetized paralyzed patients.