Background:Hypovolemia is a common cause of hypotension and low cardiac index (CI) in cardiac surgery but no hemodynamic parameters reflect this status well. The accurate diagnosis of hypovolemia is important because the wrong treatment will cause ineffectiveness and bad consequences such as severe heart failure, pulmonary edema, ... Objectives: To evaluate the performance of diagnostic characteristics of the trendelenburg 300 test for hypovolemia in cardiac surgery. Subjects and method: The prospective, cross \ufffd?sectional and randomized controlled trial (RCT) study was conducted on 30 patients (18 males, 12 females and average age 47,17 \xb1 13,93) undergoing valvular repair/replacement or coronary revascularization. The Swan \ufffd?Ganz catheters were placed in 20 patients and PiCCO catheters in 10 patients. Trendelenburg 300 test is considered positive if blood pressure (BP), central venous pressure (CVP), CI and intrathoracic blood volume (ITBV) increase. Results: The hypovolemic status in cardiac surgical patients is diagnosed if BP and/or CI increase in trendelenburg 300 position (Se 87.5% and 65.63%; Sp 100% and 75%, area under ROC 0.83 and 0.81, respectively). Conclusion: The increases in BP and CI responding to trendelenburg 300 position are good indicators of hypovolemia in cardiac surgery.
Hypovolemia/ diagnosis ; Head-Down Tilt ; Thoracic Surgery ;

BACKGROUND: It is known that pneumoperitoneum and changes of body position during laparoscopic surgery influenced peak inspiratory pressure (PIP). We asked the question whether oropharyngeal leak pressure (OLP) is changed by changes in intraabdominal pressure and position during laparoscopic surgery with a ProSeal laryngeal mask airway (PLMA). Since gynecological laparoscopic surgery (Lap-Gy) and laparoscopic cholecystectomy (Lap-C) require different surgical positions, we included both surgeries in this study so that we could investigate the effects of various positions on OLP. METHODS: Lap-Gy (n = 15) was performed in the trendelenburg position combined with the lithotomy position, whereas Lap-C (n = 10) was performed in the reverse trendelenburg position. The measured variables were PIP and OLP. We also marked the fiberoptic score to determine the intraoral position (FP) of the PLMA. OLP was measured using a manometric stability test. The variables were measured in a regular sequence as follows: S-0o-0, L-0o-0, L-0o-15, L-(-15o)-15, L-(-30o)-15 in Lap-Gy and S-0o-0, S-0o-15, S-(+15o)-15, S-(+30o)-15 in Lap-C. At each measured point, the capital S means supine and L lithotomy. Intermediate numbers with a 'o' superscript are table angles to the horizontal plane (degrees) , '-' means the trendelenburg position and '+', the reverse trendelenburg position, and the last number represents intraabdominal pressure (mmHg). RESULTS: PIP was significantly increased when L-0o-0 changed to L-0o-15, L-0o-15 to L-(-15o)-15 and L-(-15o)-15 to L-(-30o)-15 in Lap-G, and when S-0o-0 was changed to S-0o-15 in Lap-C (P < 0.05). But, OLP and FP were not significantly altered by changes in postion or intraabdominal pressure in both Lap-Gy and Lap-C. CONCLUSIONS: PIP was affected by pneumoperitoneum and positional changes. But, increases in intraabdominal pressure by pneumoperitoneum and changes in position during laparoscopic surgery had no effect on OLP and FP of PLMA.
Cholecystectomy, Laparoscopic ; Head-Down Tilt ; Laparoscopy* ; Laryngeal Masks* ; Pneumoperitoneum

The effect of anesthetic volume on the spread of hypobaric tetracaine were sutdied after intrathecal injection in thirty patients with prone jackknife and 15 degree Trendelenburg position for perinal surgery. The patients were assigned randomly into the one of three groups divided by the 3, 4, or 5 ml of volume of anesthetic solution. The results show that the volume of tetracaine in distilled water with hypobaric spinal anesthesia in prone jackknife and l5 degree Trendelenburg position had a important effect on the anesthetic dermatomal levels in spite of slightly rapid onset with large. volume. Therefore, we concluded that for the perianal surgery in prone jackknife position, as the volume of the anes- thetic solution with hypobaric spinal anesthesia, 3 or 4 ml of the volume are sufficient to get the adequate anesthetic levels.
Anesthesia, Spinal* ; Head-Down Tilt ; Humans ; Injections, Spinal ; Tetracaine ; Water

The Trendelenburg position and reverse Trendelenburg position are frequently employed during lower abdominal surgery to achieve optimal surgical field visualization and complete exposure of the operative site, particularly under pneumoperitoneum conditions. However, these positions can have significant impacts on the patient's physiological functions. This article overviews the historical background of Trendelenburg position and reverse Trendelenbury position, their effects on various physiological functions, recent advancements in their clinical applications, and strategies for preventing and managing associated complications.
Humans ; Head-Down Tilt/physiology* ; Patient Positioning ; Abdomen ; Laparoscopy

Hypotension is one of the well-known complications following spinal anesthesia, and Trendelenburg position seems to have been used as one of the management of it. But, Trendelenburg position generally raises spinal anesthetic level with the use of hyperbaric tetracaine, and blood pressure may even further decrease. If simple elevation of lower extemities can prevent hypotension successfully without raising spinal anesthetic level following hyperbaric spinal anesthesia, there will be a possibility for us to replace Trendelenburg position with the elevation of lower extremities. We examined 50 cases of hyperbaric spinal anesthesia followed by elevation of lower extremities with the angles of l5 and 30 degrees. At each case, hydration with 10 ml per Kg was performed during the fixation time (about 30 minutes) and then, blood pressure(systolic and diastolic), heart rate were checked with the time-interval of 1 and 2 minutes for each angle. The paired T-test showed that systolic and diastolic blood pressure after spinal anesthesia was increased in all cases with mean values of 2.74~5.68 mmHg for systolic blood pressure(p<0.05) and 3.26~7.22 mmHg for diastolic blood pressure(p<0.05), and that heart rate was decreased by 3.54-5.82 beats per minute(p<0.05). In conclusion, simple elevation of lower extremities and routine hydration therapy seemed to elevate blood pressure, making it possible for us to consider elevation of lower extremities to prevent hypotension without raising spinal anesthetic level in routine hyperbaric spinal anesthesia.
Anesthesia, Spinal* ; Blood Pressure ; Head-Down Tilt ; Heart Rate ; Hemodynamics* ; Hypotension ; Lower Extremity ; Tetracaine

BACKGROUND: The respiratory cycle alters the size of the right internal jugular vein (RIJV). We assessed the changes in RIJV size during the respiratory cycle in patients under positive pressure ventilation. Moreover, we examined the effects of positive-end expiratory pressure (PEEP) and the Trendelenburg position on respiratory fluctuations. METHODS: A prospective study of 24 patients undergoing general endotracheal anesthesia was performed. Images of the RIJV were obtained in the supine position with no PEEP (baseline, S0) and after applying three different maneuvers in random order: (1) a PEEP of 10 cmH2O (S10), (2) a 10degrees Trendelenburg tilt position (T0), and (3) a 10degrees Trendelenburg tilt position combined with a PEEP of 10 cmH2O (T10). Using the images when the area was smallest and largest, cross-sectional area (CSA), anteroposterior diameter, and transverse diameter were measured. RESULTS: All maneuvers minimized the fluctuation in RIJV size (all P = 0.0004). During the respiratory cycle, the smallest CSA compared to the largest CSA at S0, S10, T0, and T10 decreased by 28.3 8.5, 8.0, and 4.4%, respectively. Furthermore, compared to S0, a 10degrees Trendelenburg tilt position with a PEEP of 10 cmH2O significantly increased the CSA in the largest areas by 83.8% and in the smallest areas by 169.4%. CONCLUSIONS: A 10degrees Trendelenburg tilt position combined with a PEEP of 10 cmH2O not only increases the size of the RIJV but also reduces fluctuation by the respiratory cycle.
Anesthesia ; Head-Down Tilt* ; Humans ; Jugular Veins* ; Positive-Pressure Respiration ; Prospective Studies ; Supine Position

BACKGROUND: Femoral vein (FV) catheterization is required for critically ill patients, patients with difficult peripheral intravenous access, and patients undergoing major surgery. The purpose of this study was to evaluate the effects of hip abduction with external rotation (frog-leg position), and the frog-leg position during the reverse Trendelenburg position on diameter, cross-sectional area (CSA), exposed width and ratio of the FV using ultrasound investigation. METHODS: Ultrasonographic FV images of 50 adult subjects were obtained: 1) in the neutral position (N position); 2) in the frog-leg position (F position); 3) in the F position during the reverse Trendelenburg position (FRT position). Diameter, CSA, and exposed width of the FV were measured. Exposed ratio of the FV was calculated. RESULTS: The F and FRT positions increased diameter, CSA and exposed width of the FV significantly compared with the N position. However, the F and FRT positions had no significant effect on exposed ratio of the FV compared with the N position. The FRT position was more effective than the F position in increasing FV size. CONCLUSIONS: The F and FRT positions can be used to increase FV size during catheterization. These positions may increase success rate and reduce complication rate and, therefore, can be useful for patients with difficult central venous access or at high-risk of catheter-related complication.
Adult ; Catheterization ; Catheters ; Critical Illness ; Femoral Vein ; Head-Down Tilt ; Hip ; Humans

Although decompressive craniectomy is an effective treatment for various situations of increased intracranial pressure, it may be accompanied by several complications. Paradoxical herniation is known as a rare complication of lumbar puncture in patients with decompressive craniectomy. A 38-year-old man underwent decompressive craniectomy for severe brain swelling. He remained neurologically stable for five weeks, but then showed mental deterioration right after a lumbar puncture which was performed to rule out meningitis. A brain computed tomographic scan revealed a marked midline shift. The patient responded to the Trendelenburg position and intravenous fluids, and he achieved full neurologic recovery after successive cranioplasty. The authors discuss the possible mechanism of this rare case with a review of the literature.
Adult ; Brain ; Brain Edema ; Decompressive Craniectomy ; Head-Down Tilt ; Humans ; Intracranial Pressure ; Meningitis ; Spinal Puncture

PURPOSE: This study was carried out to evaluate the postural intraocular pressure (IOP) change in Trendelenburg, reverse Trendelenburg, and supine positions in healthy young males. METHODS: We measured the IOP values of 5 healthy young male volunteers (10 eyes) using an Icare PRO rebound tonometer in sitting, Trendelenburg, reverse Trendelenburg, and supine positions. RESULTS: The mean IOP in the supine position (18.63 mm Hg) was significantly higher (p < 0.01) than in the sitting position (15.31 mm Hg). When maintaining the Trendelenburg position, IOP gradually increased. CONCLUSIONS: In our study, the Trendelenburg position significantly increased the IOP compared to that in the supine position. The effects of increased IOP should be considered in situations that require Trendelenburg positioning, such as exercise or surgery.
Head-Down Tilt ; Humans ; Intraocular Pressure* ; Iron-Dextran Complex ; Male ; Supine Position ; Volunteers

BACKGROUND: It has been reported that spinal anesthesia has a sedative effect and so this decreases the hypnotic requirement of intravenous anesthetic. Therefore, we have conducted a prospective randomized study to investigate the effect of the spinal anesthesia level on the hypnotic requirements for conscious sedation. METHODS: Forty adult patients were scheduled to undergo spinal anesthesia, and they were randomly allocated to one of the two groups. After subarachnoid injection of 0.5% hyperbaric bupivacaine 16 mg, the patients in group 1 and group 2 were maintained in a reversed Trendelenburg position and a Trendelenburg position, respectively. After fifteen minutes, the target controlled infusion of propofol was started for achieving a target concentration of 1 microgram/ml, and the mean BIS for 1 min was checked after an effect site concentration (Ce) of 1 microgram/ml was reached. The target controlled infusion of propofol was restarted at a target concentration (Tc) of 1.5 microgram/ml, and the mean BIS for 1 min was checked after the Ce level of 1.5 microgram/ml was reached. RESULTS: The mean BIS at 1 microgram/ml Ce was 90.0 +/- 8.5 and 77.8 +/- 10.3 in group 1 and group 2, respectively. The mean BIS at 1.5 g/ml Ce was 73.6 +/- 19.4 and 60.0 +/- 13.1, respectively. CONCLUSIONS: There was a significant difference in the requirements of propofol for conscious sedation between the below T12 block group and the above T4 block group.
Adult ; Anesthesia, Spinal ; Bupivacaine ; Conscious Sedation ; Head-Down Tilt ; Humans ; Hypnosis ; Hypnotics and Sedatives ; Propofol* ; Prospective Studies