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Juraj Sprung

Publications and source records attributed to Juraj Sprung.

46 records · Page 3Linked to original sources

The effects of tidal volume and respiratory rate on oxygenation and respiratory mechanics during laparoscopy in morbidly obese patients.

UNLABELLED: Morbidly obese (MO) patients undergoing laparoscopy have lower PaO(2) compared with normal-weight (NW) patients. We hypothesized that increases in tidal volume (V(T)) or respiratory rate (RR) would improve oxygenation. All measurements were performed at: 1) baseline: V(T) 600-700 mL and 10 breaths/min, 2) double V(T): V(T) 1200-1400 mL and 10 breaths/min, and 3) double rate: V(T) 600-700 mL and 20 breaths/min. We calculated static respiratory system compliance (Cst,rs) and inspiratory resistance (RI,rs). End-tidal CO(2) was measured with a mass spectrometer, and PaO(2) and PaCO(2) with a continuous blood gas monitor. Supine anesthetized MO patients had 29% lower Cst,rs than the NW patients (P < 0.05). Positioning patients head-up or head-down before pneumoperitoneum did not significantly affect Cst,rs in either group (P = 0.8). Doubling the V(T), but not RR, increased Cst,rs in both groups. Pneumoperitoneum caused large decreases in Cst,rs in both groups (both P < 0.001). During pneumoperitoneum, changing the body position, V(T), or RR did not further affect Cst,rs in either group (P > 0.7). Before pneumoperitoneum, RI,rs was higher in the MO patients compared with the NW patients regardless of body position (P = 0.01). Doubling either RR or V(T) before pneumoperitoneum did not change RI,rs in either group. After pneumoperitoneum, RI,rs increased in both the head-down and head-up positions (P < 0.05), but not in the supine position. Regardless of the conditions studied, alveolar-arterial difference in oxygen tension was always significantly higher in MO patients (P < 0.05). The alveolar-arterial difference in oxygen tension was not affected by body position, pneumoperitoneum, or the mode of ventilation. Arterial oxygenation during laparoscopy was affected only by body weight and could not be improved by increasing either the V(T) or RR. IMPLICATIONS: Morbid obesity decreases arterial oxygenation and respiratory system compliance. During laparoscopy, arterial oxygenation is affected only by the patient's body weight. Increases in tidal volume or respiratory rate do not improve arterial oxygenation.

Adult↗

Transurethral resection syndrome after bladder perforation.

The use of irrigating solutions is essential for distension of mucosal surfaces and visualization of the surgical field during resectoscopic resection of bladder tumors (TURBT). TURBT resection may be complicated with bladder perforation associated with intraperitoneal extravasation of irrigant fluid, which may rarely evolve in specific hydroelectrolyte imbalance characterized with hyponatremia, intravascular volume deficit, and renal impairment. We report four cases of TURBT syndrome during bladder surgery complicated by bladder perforation and discuss issues relevant to pathophysiology, diagnosis, and treatment of this rare condition.

Aged↗

Echocardiographic and hemodynamic evaluation of cardiovascular performance during laparoscopy of morbidly obese patients.

BACKGROUND: The effects of morbid obesity, pneumoperitoneum (PP) and body position on cardiac function during laparoscopy were studied. METHODS: Transesophageal echocardiography (TEE) was performed on 10 obese patients (body mass index, BMI, 48.1+/-1.8 kg/m2) and 10 normal weight patients (BMI = 22.6+/-0.8 kg/m2) in supine, Trendelenburg and reverse Trendelenburg positions before and after PP. Left ventricular end-systolic wall stress (LVESWS) was calculated from invasive blood pressure (BP) values and LV dimensions obtained by TEE. Diastolic filling was assessed by mitral valve and pulmonary vein flow velocities. RESULTS: LVESWS was higher in obese patients both at baseline (46.0+/-4.0 x 10(3) dyn/cm2) and with PP (69.3+/-8.2 x 10(3) dyn/cm2), than normal weight subjects (31.9+/-3.7 x 10(3) dyn/cm2 and 45.7+/-5.9 x 10(3) dyn/cm2; P <0.05 obese vs normal weight patients at baseline). Systolic BP was not different between groups at baseline (normal weight 111+/-4 mmHg, obese 119+/-3 mmHg), but increased significantly with PP only in obese patients (normal weight 129+/-6 mmHg, obese 157+/-8 mmHg; P <0.05). Postural changes during PP had no impact on cardiac function in either obese or normal weight subjects. CONCLUSIONS: Anesthetized obese patients undergoing laparoscopy have higher LVESWS before pneumoperitoneum (due to increased end-systolic left ventricular dimensions) and during pneumoperitoneum (due to more pronounced increases in blood pressure). Since LVESWS is a determinant of myocardial oxygen demand, more aggressive control of blood pressure (ventricular afterload) in MO patients may be warranted to optimize the myocardial oxygen requirements.

Adult↗

Ondansetron-induced multifocal encephalopathy.

We treated a patient who developed transient multifocal encephalopathy with extrapyramidal symptoms (oromandibular dystonia, oculogyric crisis, and limb dystonia) in temporal proximity to ondansetron administration on emergence from general anesthesia. No other medications known to cause extrapyramidal reactions were administered. Although these symptoms resolved fully, the presentation was dramatic and resembled the symptoms of structural brain injury. Ondansetron is used frequently as an antiemetic agent in many clinical settings and is not limited to surgical patients. Therefore, the entire medical community should be cognizant of this potential adverse reaction.

Antiemetics↗

The use of bovine hemoglobin glutamer-250 (Hemopure) in surgical patients: results of a multicenter, randomized, single-blinded trial.

UNLABELLED: Hemoglobin-based oxygen carrier-201 (HBOC-201, hemoglobin glutamer-250 [bovine], Hemopure; Biopure Corporation, Cambridge, MA) is polymerized hemoglobin of bovine origin being developed as an oxygen therapeutic. In this study, we evaluated the tolerability of a single intraoperative dose of HBOC-201 in surgical patients. In a single-blinded, multicenter study, 81 patients were randomized to receive either a single infusion of HBOC-201 (55 patients) or an equivalent volume of lactated Ringer's solution (26 patients). Forty-two patients originally assigned to the HBOC-201 group received the entire planned treatment of only one of the following doses: 0.6, 0.9, 1.2, 1.5, 2.0, or 2.5 g/kg of body weight. Thirteen of the 55 patients in the HBOC-201-assigned group did not reach the trigger point for transfusion administration, and they were not included in the analysis. We studied clinical outcomes and compared hematologic findings, blood chemistry values, and blood use in the two treatment groups. There were no patient deaths in this study. No pattern of clinically significant laboratory abnormalities could be attributed to exposure to HBOC-201. In the HBOC-201 group, 2 patients had a transient increased concentration of serum transaminases and 6 had transient skin discoloration. One patient in the HBOC-201 group had mast cell degranulation with hypotension. Postoperatively, methemoglobin plasma concentrations increased in the HBOC-201 group in a dose-dependent manner, reaching maximal values of 3.7% +/- 3.2% (average of all doses given) on postoperative day 3. There was no difference in the mean number of allogeneic blood units transfused in the 2 groups (3.3 +/- 1.8 and 3.7 +/- 4.1 for the lactated Ringer's solution and HBOC-201 groups, respectively) over the course of hospitalization. The intraoperative administration of HBOC-201, up to a maximum of 245 g, was generally well tolerated. There was no relationship between HBOC-201 use and the number of allogeneic blood units transfused over the entire hospitalization course. The administration of HBOC-201 was associated with a delayed (third postoperative day) dose-dependent increase in the plasma methemoglobin concentration. We conclude that the intraoperative use of HBOC-201 was generally well tolerated. IMPLICATIONS: The intraoperative use of hemoglobin glutamer-250 (bovine) (HBOC-201, Hemopure was generally well tolerated. The administration of HBOC-201 was associated with a delayed increase in the plasma methemoglobin concentrations.

Adolescent↗

The impact of morbid obesity, pneumoperitoneum, and posture on respiratory system mechanics and oxygenation during laparoscopy.

UNLABELLED: We studied the effect of morbid obesity, 20 mm Hg pneumoperitoneum, and body posture (30 degrees head down and 30 degrees head up) on respiratory system mechanics, oxygenation, and ventilation during laparoscopy. We hypothesized that insufflation of the abdomen with CO(2) during laparoscopy would produce more impairment of respiratory system mechanics and gas exchange in the morbidly obese than in patients of normal weight. The static respiratory system compliance and inspiratory resistance were computed by using a Servo Screen pulmonary monitor. A continuous blood gas monitor was used to monitor real-time PaCO(2) and PaO(2), and the ETCO(2) was recorded by mass spectrometry. Static compliance was 30% lower and inspiratory resistance 68% higher in morbidly obese supine anesthetized patients compared with normal-weight patients. Whereas body posture (head down and head up) did not induce additional large alterations in respiratory mechanics, pneumoperitoneum caused a significant decrease in static respiratory system compliance and an increase in inspiratory resistance. These changes in the mechanics of breathing were not associated with changes in the alveolar-to-arterial oxygen tension difference, which was larger in morbidly obese patients. Before pneumoperitoneum, morbidly obese patients had a larger ventilatory requirement than the normal-weight patients to maintain normocapnia (6.3 +/- 1.4 L/min versus 5.4 +/- 1.9 L/min, respectively; P = 0.02). During pneumoperitoneum, morbidly obese, supine, anesthetized patients had less efficient ventilation: a 100-mL increase of tidal volume reduced PaCO(2) on average by 5.3 mm Hg in normal-weight patients and by 3.6 mm Hg in morbidly obese patients (P = 0.02). In conclusion, respiratory mechanics during laparoscopy are affected by obesity and pneumoperitoneum but vary little with body position. The PaO(2) was adversely affected only by increased body weight. IMPLICATIONS: Morbid obesity significantly decreases respiratory system compliance and increases inspiratory resistance. Increased body weight, and not altered mechanics of breathing, was associated with worse PaO(2) during laparoscopy.

Adult↗

The effect of dopamine on renal function in solitary partial nephrectomy surgery.

PURPOSE: Dopamine continues to be used for preventing and treating acute renal failure. We determined the effects of dopamine on postoperative renal function in patients with a solitary kidney undergoing partial nephrectomy. MATERIALS AND METHODS: We performed a prospective randomized controlled study at a tertiary care referral center involving 24 patients with a solitary kidney undergoing partial nephrectomy secondary to malignancy. Patients were randomized to receive dopamine (11) [corrected] or no dopamine (13) [corrected]. Intraoperatively those assigned to the dopamine group received a 3 microg./kg. per minute dopamine infusion. Patients in each group received an adequate amount of fluid to maintain good urine production, systemic blood pressure and central venous pressure. Serum electrolytes, blood urea nitrogen, creatinine, serum and urine osmolality, and urine output were measured at baseline, intraoperatively and through postoperative day 4. Preoperatively and postoperatively renal blood flow and the glomerular filtration rate were measured. RESULTS: In the 2 groups blood urea nitrogen and serum creatinine increased postoperatively. Although the degree of this increase showed a trend to be lower in the dopamine group, the difference did not reach statistical significance. There was no difference in renal blood flow or the glomerular filtration rate in the treatment groups. CONCLUSIONS: Administering dopamine to patients with a solitary kidney undergoing partial nephrectomy provided no renoprotective effect.

Blood Pressure↗