Significant Increase In Central Venous Pressure Research Articles

Measuring intraoperative anesthetic parameters during hepatectomy with inferior vena cava clamping.

Uncontrollable bleeding remained problematic in anatomical hepatectomy exposing hepatic veins. Based on the inferior vena cava (IVC) anatomy, we attempted to analyze the hemodynamic and surgical effects of the combined IVC-partial clamp (PC) accompanied with the Trendelenburg position (TP). We prospectively assessed 26 consecutive patients who underwent anatomical hepatectomies exposing HV trunks between 2020 and 2023. Patients were divided into three groups: use of IVC-PC (group 1), no use of IVC-PC (group 2), and use of IVC-PC accompanied with TP (group 3). In 10 of 26 patients (38%), hepatic venous pressure was examined using transhepatic catheter insertion. IVC-PC was performed in 15 patients (58%). Operating time and procedures did not significantly differ between groups. A direct hemostatic effect on hepatic veins was evaluated in 60% and 70% of patients in groups 1 and 3, respectively. Group 1 showed significantly more unstable vital status and vasopressor use (p < 0.01). Blood or fluid transfusion and urinary output were similar between groups. Group 2 had a significantly lower baseline central venous pressure (CVP), while group 3 showed a significant increase in CVP in TP. CVP under IVC-PC seemed lower than under TP; however, not significantly. Hepatic venous pressure did not significantly differ between groups. Systolic arterial blood pressure significantly decreased via IVC-PC in group 1 and to a similar extent in group 3. Heart rate significantly increased during IVC-PC (p < 0.05). IVC-PC combined with the TP may be an alternative procedure to control intrahepatic venous bleeding during anatomical hepatectomy exposing hepatic venous trunks.

Venous waveform analysis detects acute right ventricular failure in a rat respiratory arrest model.

Peripheral intravenous analysis (PIVA) has been shown to be more sensitive than central venous pressure (CVP) for detecting hemorrhage and volume overload. We hypothesized that PIVA is superior to CVP for detecting right ventricular (RV) failure in a rat model of respiratory arrest. Eight Wistar rats were studied in accordance with the ARRIVE guidelines. CVP, mean arterial pressure (MAP), and PIVA were recorded. Respiratory arrest was achieved with IV Rocuronium. PIVA utilizes Fourier transform to quantify the amplitude of the peripheral venous waveform, expressed as the "f1 amplitude". RV diameter was measured with transthoracic echocardiography. RV diameter increased from 0.34 to 0.54 cm during arrest, p = 0.001, and returned to 0.33 cm post arrest, p = 0.97. There was an increase in f1 amplitude from 0.07 to 0.38 mmHg, p = 0.01 and returned to 0.08 mmHg, p = 1.0. MAP decreased from 119 to 67 mmHg, p = 0.004 and returned to 136 mmHg, p = 0.50. There was no significant increase in CVP from 9.3 mmHg at baseline to 10.5 mmHg during respiratory arrest, p = 0.91, and recovery to 8.6 mmHg, p = 0.81. This study highlights the utility of PIVA to detect RV failure in small-caliber vessels, comparable to peripheral veins in the human pediatric population. Right ventricular failure remains a diagnostic challenge, particularly in pediatric patients with small vessel sizes limiting invasive intravascular monitor use. Intravenous analysis has shown promise in detecting hypovolemia and volume overload. Intravenous analysis successfully detects right ventricular failure in a rat respiratory arrest model. Intravenous analysis showed utility despite utilizing small peripheral venous access and therefore may be applicable to a pediatric population. Intravenous analysis may be helpful in differentiating various types of shock.

Influence of the Trendelenburg position and carboxyperitoneum on cerebral tissue oximetry values

Background. Cerebral tissue oximetry (rSO2) can be used to assess cerebral circulation. Cerebral tissue oximetry studies have been performed in the Trendelenburg position (30º), but data for 45 o are not available.Objective. To study the effect of the Trendelenburg position (45°) under carboxyperitoneum conditions on rSO2 and hemodynamic parameters.Design and methods. A single-center, prospective, descriptive study was conducted among patients (n = 30) who underwent robot-assisted laparoscopic prostatectomy. We measured rSO2 on the left and right, central venous pressure (CVP), mean arterial pressure (MAP), venous saturation at points: T1 — after induction of anesthesia and start of measurements; T2 — 5 minutes after positioning the patient in the Trendelenburg position of 45o; T3 — 15 minutes; T4 — 30 minutes; T5 — after returning to a horizontal position. Cerebral perfusion was assessed using cerebral perfusion pressure (CPP).Results. rSO2 on the right and left at points T2, T3 and T5 significantly exceeded T1. There was a significant increase in BP mean at T2 and T3, as well as a significant increase in CVP at T2, T3 and T4 compared to T1. The CPP significantly decreased compared to T1 at points T3, T4 and T5.Conclusions. The Trendelenburg position with a tilt angle of 45º in combination with carboxyperitoneum is accompanied by an increase in rSO2, blood pressure and CVP.

Role of lung ultrasound in assessment of endpoint of fluid therapy in patients with hypovolemic shock

ABSTRACT Background: Different techniques are employed to assess the endpoint of fluid therapy in hypovolemic patients. Lung ultrasound (US) is increasingly becoming a diagnostic tool in the critical care setting, providing standardized data. The present study aimed to evaluate the role of lung US in comparison to central venous pressure (CVP) in assessment of endpoint of fluid therapy in patients with hypovolemic shock. Patients and methods: Observational cross-sectional study carried in 60 adult patients with hypovolemic shock admitted to the intensive care unit received lactated Ringer’s solution. CVP, blood pressure (BP), urine output (UOP), and lung US score were recorded on admission and during the period of resuscitation. Lung US score was correlated with CVP, BP, and UOP and evaluated in assessment of endpoint fluid therapy in comparison to CVP as a gold standard. Results: There was a significant increase in CVP, BP, UOP,and lung US score during fluid resuscitation. Lung US showed a significant positive correlation with CVP, BP, and UOP at different stages of fluid resuscitation. Lung US score showed a sensitivity of 95.7%, specificity of 92.9% with a positive predictive value of 97.8% negative predictive value of 86.7%, and the total accuracy was 95%. Conclusion: Lung US provides a simple noninvasive approach in assessment of endpoint (score ≥16) of fluid therapy in patients with hypovolemic shock with high sensitivity and specificity.

Effect of Anesthesia on Cardiac Hemodynamics in patients undergoing durable LVAD Implantation: The EACHLVAD Study

Purpose Right ventricular (RV) dysfunction is often unmasked or exacerbated during implantation of a left ventricular assist device (LVAD). Prior to LVAD implantation, the effect of anesthesia induction on RV performance is unknown. We assessed for early hemodynamic changes in the RV after induction, prior to initiation of cardiopulmonary bypass (CPB), in the presence or absence of preoperative temporary mechanical circulatory support (tMCS). Methods We prospectively collected hemodynamic measurements in patients undergoing LVAD implantation at a large academic institution between 9/2017 and 9/2018. Preoperative RV hemodynamics were compared to RV hemodynamics post-induction and intubation but prior to CPB, including central venous pressure (CVP), mean pulmonary artery pressure (mPAP), and pulmonary artery pulsatility index (PAPi). Serial hemodynamics and vasoactive inotropic score (VIS) were analyzed over time using random effects models, adjusting for induction agents and use of pre-operative tMCS. Results There were 41 patients included in this analysis, with 4 intubated prior to induction. There was a significant increase in CVP (3.6 mmHg, p intra-aortic balloon pumps were 14 of 17 tMCS cases and had similar reduction in PAPi at all time points (-2.5, p Conclusion RV hemodynamics acutely worsen after anesthesia induction prior to bypass initiation in LVAD recipients. Patients with preoperative tMCS have worse RV hemodynamics at each timepoint but less significant decline over time.

Airway pressure release ventilation does not increase intracranial pressure in patients with traumatic brain injury with poor lung compliance

The use of Airway Pressure Release Ventilation (APRV) in patients with traumatic brain injury (TBI) remains controversial. Some believe that elevated mean airway pressures transmitted to the thorax may cause clinically significant increases in Central Venous Pressure (CVP) and intracranial pressure (ICP) from venous congestion. We perform a retrospective review from 2009 to 2015 of traumatically injured patients who were transitioned from traditional ventilator modes to APRV and also had an ICP monitor in place. Fifteen patients undergoing 19 transitions to APRV were identified. Prior to transitioning to APRV the average static and dynamic compliance was 22.9 +/− 5.6 and 16.5 +/− 4.12 mL/cm H2O. There was no statistical difference in ICP, MAP, and CPP prior to and after transition to APRV. There was a statistically significant increase in CVP, PaO2, and P:F ratio. Individually, only 4 patients had ICP values >20 in the first hour after transitioning to APRV and the rate of ICP elevations was similar between the two modes of ventilation. These data show that APRV is a viable mode of ventilation in patients with TBI who have low lung compliance. The increased CVP of this mode of ventilation did not affect ICP or hemodynamic parameters.

Responsiveness of stroke volume variation and central venous pressure during acute normovolemic and hypervolemic hemodilution.

Stroke volume variation (SVV) is a robust indicator of fluid responsiveness during volume change. We compared the sensibility of SVV by Vigileo/Flotrac to central venous pressure (CVP) when volume changes in patients undergoing intraoperative acute normovolemic hemodilution (ANH) and acute hypervolemic hemodilution (AHH). Forty patients were randomly divided into an ANH group (n = 20) and an AHH group (n = 20). All patients received general anesthesia and were mechanically ventilated. Data were collected from 7 different time-points in the ANH group: baseline, after withdrawal of 5%, 10%, and 15% of the estimated blood volume (EBV) and after replacement with an equal volume of 6% hydroxyethyl starch 130/0.4 (HES) in 5% EBV increments to baseline. There were four time points in the AHH group: baseline, after 5%, 10%, and 15% expansion of the EBV with 6% HES. At each time-point, CVP, SVV and other hemodynamic parameters measurements were obtained. After removal of 10% and 15% EBV, SVV significantly increased from 10.9 ± 3.0 to 14.1 ± 3.4 and 10.9 ± 3.0 to 16.0 ± 3.3 (P < 0.01), and returned to a final value of 10.6 ± 3.4 after volume replacement. The CVP value was unchanged after removal and replacement of 15% of the EBV. There were no significant changes in SVV after 5%, 10% whereas there was a significant reduction after 15% (8.2 ± 1.7) expansion of the EBV compared with baseline (9.9 ± 1.8) (P = 0.033). However, there was a significant increase in CVP after 10% (10.3 ± 2.4), 15% (11.3 ± 2.2) expansion of the EBV compared with baseline (8.2 ± 2.7) (P < 0.01). SVV is a more sensitive parameter for volume than CVP during hypovolemia, on the contrary CVP is more sensitive than SVV during hypervolemia.

Evaluation of Central Venous Pressure Monitoring in Children Undergoing Craniofacial Reconstruction Surgery

Massive hemorrhage during craniofacial surgery is common and often results in hypovolemia and hypotension. We conducted this study to assess the effect of the addition of routine central venous pressure (CVP) monitoring on the incidence of intraoperative hypotension and to evaluate the relationship between CVP and hypotension in this population. Data from our prospective craniofacial perioperative registry for children 6 to 24 months of age undergoing cranial vault reconstruction with CVP monitoring were compared with data from a historical cohort without CVP monitoring. The incidence and duration of hypotension in the 2 cohorts were compared. In the cohort of subjects with CVP monitoring who experienced hypotension, CVP at the onset of hypotension (T0) was compared with CVP 5 minutes before (T-5) and 5 minutes after (T+5) the onset of hypotension and with the baseline CVP. The amount of time spent at various CVP levels below the baseline, and the associated incidence of hypotension were also determined. Data from 57 registry subjects were compared with data from 115 historical cohort subjects. The median total duration of hypotension in subjects experiencing hypotension was 278 seconds in the CVP cohort versus 165 seconds in the historical cohort; the median difference was 98 seconds (95% confidence interval [CI], -45 to 345 seconds). The incidence of hypotension was 18% in the CVP cohort versus 21% in the historical cohort; the difference in the incidence of hypotension was -3% (95% CI, -10% to 15%). Analysis using a linear mixed effects model showed a significant decrease in CVP from T-5 to T0 (95% CI, -0.9 to -2.2 mm Hg), a significant increase in CVP from T0 to T+5 (95% CI, 1.0-2.4 mm Hg), no significant difference in CVP between T-5 and T+5 (95% CI, -0.9 to 0.9 mm Hg), and a significant decrease in CVP from baseline to T0 (95% CI, -3.4 to -2.1 mm Hg). CVP at T0 was less than the baseline CVP in 97% of hypotensive episodes. When all cases were examined, CVP was ≥3 mm Hg below the baseline for 16% of the total time studied, with an associated incidence of hypotension of 2%. The implementation of routine CVP monitoring was not associated with a decreased incidence and likely was not associated with a decreased duration of hypotension in this population experiencing massive hemorrhage. Hypotension was associated with a decrease in CVP, and resolution of hypotension was associated with an increase in CVP to prehypotensive levels. However, significant decreases in CVP below the baseline were common and usually not associated with hypotension. The routine use of CVP monitoring in these children is of questionable utility as a means to decrease the incidence and duration of hypotension.

The effects of L‐659,066, a peripheral α2‐adrenoceptor antagonist, and verapamil on the cardiovascular influences of dexmedetomidine in conscious sheep

We investigated whether administration of L-659,066, a peripheral α(2) -adrenoceptor antagonist, or verapamil, a calcium-channel antagonist, would prevent the cardiovascular effects of dexmedetomidine. Eleven sheep received three intravenous treatments with a randomized, cross-over design: dexmedetomidine (5 μg/kg, DEX); DEX with L-659,066 (250 μg/kg, DEX + L); and verapamil (0.05 mg/kg) 10 min prior to DEX (Ver + DEX). Haemodynamics were recorded at intervals upto 40 min. Acute increases in mean arterial pressure (MAP) (106 ± 10.7 to 120.8 ± 11.7 mmHg), central venous pressure (CVP) (3.3 ± 3.2 to 14.7 ± 5.0 mmHg) and systemic vascular resistance (SVR) (1579 ± 338 to 2301 ± 523 dyne s/cm(5) ), and decreases in cardiac output (CO) (5.36 ± 0.87 to 3.93 ± 1.30 L/min) and heart rate (HR) (88.6 ± 15.3 to 49.7 ± 5.5/min) were detected with DEX. The peak SVR remained lower after Ver + DEX (1835 ± 226 dyne s/cm(5) ) than DEX alone, but the other parameters did not significantly differ between these treatments. 2 min after drug delivery, differences between DEX and DEX + L were statistically significant for all measured haemodynamic parameters. With DEX + L, an early decrease in MAP (99.9 ± 6.8 to 89.3 ± 6.6 mmHg) was detected, and DEX + L induced a slight but significant increase in CVP and a decrease in HR at the end of the observation period, while SVR and CO did not significantly change. All animals were assessed as deeply sedated from 2-20 min with no differences between treatments. L-659,066 has great potential for clinical use to prevent the cardiovascular effects of dexmedetomidine mediated by peripheral α(2) -adrenoceptors, whereas the effects of verapamil were marginal.

Effects of Posture and Prolonged Pneumoperitoneum on Hemodynamic Parameters during Laparoscopy

The present prospective study was designed to evaluate hemodynamic changes associated with head-down positioning and prolonged pneumoperitoneum during totally endoscopic robot-assisted radical prostatectomy. Ten American Society of Anesthesiologists (ASA) physical status I-III patients undergoing totally endoscopic robot-assisted radical prostatectomy were enrolled in the study. Invasive hemodynamic parameters were measured by transpulmonary arterial thermodilution using the PiCCO system with a femoral artery catheter. Cardiac index (CI), heart rate (HR), mean arterial pressure (MAP), systemic vascular resistance index (SVRI), intrathoracic blood volume (ITBV), and central venous pressure (CVP) were recorded with the patient in the supine position, after head-down tilt, intraoperatively after 30 min, 1 h, 2 h, 3 h, and 4 h of pneumoperitoneum at an insufflation pressure of 12 mmHg, after deflation still with head-down positioning, and finally, with the patient in the supine position. Placing the patient in the Trendelenburg (head-down) position caused a significant increase in CVP (from 9.9 +/- 3.4 to 15.1 +/- 2.3 mmHg), whereas all other hemodynamic parameters remained nearly unaffected. The induction of pneumoperitoneum resulted in a significant increase in MAP (from 74.9 +/- 12.9 to 95.4 +/- 11.9 mmHg). No other parameter was affected. Even at 4 h of pneumoperitoneum only mild hemodynamic changes were observed. After release of the pneumoperitoneum with the patient still in the head-down position, HR (49.0 +/- 4 versus 63.9 +/- 12.4 min(-1)) and after placing the patient in the supine position, CI (2.4 +/- 0.2 versus 3.3 +/- 0.7 l min(-1 )m(-2)) increased significantly, whereas CVP returned to baseline values. Patients undergoing totally endoscopic radical prostatectomy with 4 h of pneumoperitoneum in the Trendelenburg position experienced no significant hemodynamic depression during posture and pneumoperitoneum.

Cardiopulmonary Effects of Intrathoracic Insufflation in Dogs

This study was designed to quantify the effects of incremental positive insufflation of the intrathoracic space on cardiac output (CO), heart rate (HR), arterial pressure (AP), central venous pressure (CVP), and percent saturation of hemoglobin with oxygen (SPO2) in anesthetized dogs. Seven healthy, adult dogs from terminal teaching laboratories were maintained under anesthesia with isoflurane delivered with a mechanical ventilator. The experimental variables were recorded before introduction of an intrathoracic catheter, at intrathoracic pressures (IP) of 0 mm Hg, 3 mm Hg insufflation, and additional increments of 1 mm Hg insufflation thereafter until the SPO2 remained <85% despite increases in minute volume. Finally the variables were measured again at 0 mm Hg IP. The cardiac output and systolic and diastolic AP significantly (P < 0.05) decreased at 3 mm Hg IP. Significant decreases in SPO2 were seen at 10 mm Hg IP. Significant increase in CVP was noted at 6 mm Hg IP. Heart rate decreased significantly at 5 to 6 mm Hg IP but was not decreased above 6 mm Hg IP. Given the degree of CO decrease at low intrathoracic pressures, insufflation-aided thoracoscopy should be used with caution and at the lowest possible insufflation pressure. Standard anesthetic monitoring variables such as HR and AP measurements may not accurately reflect the animal's cardiovascular status.

Endoscopic endocrine neck surgery with carbon dioxide insufflation: The effect on intracranial pressure in a large animal model

Background. Endoscopic endocrine neck surgery requires insufflation with carbon dioxide (CO2) at 10 to 15 mm Hg, which may decrease the cerebral venous return and increase intracranial pressure. This study evaluated the effect of CO2 neck insufflation on intracranial pressure (ICP) and hemodynamic parameters. Methods. Fifteen pigs underwent endoscopic thyroid dissection. Insufflation was performed with CO2 at 0 (sham), 10, 15, and 20 mm Hg and with helium at 20 mm Hg with 3 pigs in each group. ICP, mean arterial pressure, central venous pressure (CVP), cardiac output, and blood gas were measured at baseline, 30, 60, and 120 minutes. Results. There were no differences in mean ICP between the sham group and CO2 insufflation at 10 mm Hg. Mean ICP increased significantly with CO2 at 15 and 20 mm Hg and with helium at 20 mm Hg. A significant increase in CVP occurred in pigs operated with CO2 at 20 mm Hg. We observed jugular vein collapse under all insufflation pressures; however, pigs operated at 10 mm Hg were able to maintain an intermittent blood flow. Conclusions. A severe increase in ICP occurs with insufflation pressures higher than 15 mm Hg, possibly as a result of decreased cervical venous blood flow. Carbon dioxide insufflation up to 10 mm Hg does not alter ICP and is recommended for clinical application in endoscopic neck surgery. (Surgery 2000;128:1035-42.)

Role of vagal afferents in hypotension induced by venous air embolism

To evaluate the role of the autonomic nervous system in the development of hypotension during air embolism, we studied the effects of an intravenous bolus injection of air (0.5 ml/kg) on mean blood pressure (MBP), central venous pressure (CVP), and renal nerve activity (RNA) in urethan-anesthetized rabbits of three groups: animals with an intact neuraxis (intact group; n = 5), cervical-vagotomized animals (vagotomy group; n = 5), and sinoaortic-denervated animals (SAD group; n = 5). In the intact group, despite a significant decrease in MBP at 10 s after air injection, RNA did not increase from the preinjection level. This response of RNA was associated with a significant increase in CVP and lasted for 20 s after the injection. Vagotomized animals, however, exhibited a significant augmentation in RNA in response to a drop in MBP at 10 s after the injection. In the SAD group, profound declines in both MBP and RNA were observed at 10 s after the injection of air. Animals in these two groups showed remarkable increases in CVP. At 5 min after the air administration, MBP in the vagotomy group was significantly higher than that in the intact group. All animals in the SAD group died within 5 min of the injection. These results indicate that during hypotension induced by air injection, sympathetic activation through arterial baroreceptors may be depressed by vagal afferents emanating from cardiopulmonary receptors; the results also suggest that the arterial baroreceptor nerves may be required to overcome the lethal events that should occur during venous air embolism.

Central venous pressure in humans during short periods of weightlessness.

Central venous pressure (CVP) was measured in 14 males during 23.3 +/- 0.6 s (mean +/- SE) of weightlessness (0.00 +/- 0.05 G) achieved in a Gulfstream-3 jet aircraft performing parabolic flight maneuvers and during either 60 or 120 s of +2 Gz (2.0 +/- 0.1 Gz). CVP was obtained using central venous catheters and strain-gauge pressure transducers. Heart rate (HR) was measured simultaneously in seven of the subjects. Measurements were compared with values obtained inflight at 1 G with the subjects in the supine (+1 Gx) and upright sitting (+1 Gz) positions, respectively. CVP was 2.6 +/- 1.5 mmHg during upright sitting and 5.0 +/- 0.7 mmHg in the supine position. During weightlessness, CVP increased significantly to 6.8 +/- 0.8 mmHg (P less than 0.005 compared with both upright sitting and supine inflight). During +2 Gz, CVP was 2.8 +/- 1.4 mmHg and only significantly lower than CVP during weightlessness (P less than 0.05). HR increased from 65 +/- 7 beats/min at supine and 70 +/- 5 beats/min during upright sitting to 79 +/- 7 beats/min (P less than 0.01 compared with supine) during weightlessness and to 80 +/- 6 beats/min (P less than 0.01 compared with upright sitting and P less than 0.001 compared with supine) during +2 Gz. We conclude that the immediate onset of weightlessness induces a significant increase in CVP, not only compared with the upright sitting position but also compared with the supine position at 1 G.

CARDIOVASCULAR EFFECTS OF EXTRADURAL ANALGESIA IN LABOUR: COMPARISON OF BUPIVACAINE WITH LIGNOCAINE

Two groups of patients who requested extradural analgesia were studied in a within-patient controlled trial and received either 0.5% bupivacaine with adrenaline 5 mug/ml or 0.5% bupivacaine plain as the analgesic agent (first group) or 0.5% bupivacaine or 2% lignocaine both with adrenaline 5 mug/ml (second group). Arterial pressure, central venous pressure (CVP), maternal and foetal heart rate and uterine contractions were monitored continuously. There was no significant difference in any of the cardiovascular measurements when solutions of 0.5% bupivacaine (with or without adrenaline 5 mug/ml) were used. The second group had a statistically significant increase in CVP during the study period in which 2% lignocaine was used. The position of the patient did not affect the cardiovascular measurements in either group. Since the addition of adrenaline 5 mug/ml to bupivacaine solutions did not confer any apparent advantages, it is concluded that plain solutions of 0.5% bupivacaine should be used except in the longest labours.