Central Venous Pressure Values Research Articles

Avaliação da buprenorfina pelas vias intravenosa ou intramuscular em cães anestesiados pelo desfluorano

Objetivou-se avaliar comparativamente os efeitos da buprenorfina, administrada pelas vias intramuscular(IM) ou intravenosa (IV), sobre variáveis cardiovasculares, em cães anestesiados com desfluorano. Para tanto, foram utilizados dezesseis cães adultos, clinicamente saudáveis, distribuídos em dois grupos (n=8) denominados de GI e GII. Em ambos os grupos, a anestesia foi induzida com propofol (8 mg/kg, IV) e em seguida os animais foram intubados com sonda orotraqueal de Magill, a qual foi conectada ao aparelho de anestesia volátil para administração de desfluorano (1,5 CAM). Após 30 minutos do início da anestesia inalatória, foi aplicado no GI buprenorfina na dose de 0,02 mg/kg pela via IV, enquanto no GII administrou-se o opióide na mesma dose porém pela via IM. Avaliaram-se: freqüência cardíaca (FC); pressões arteriais sistólica, diastólica e média (PAS, PAD e PAM); débito cardíaco (DC); pressão venosa central (PVC) e pressão da artéria pulmonar (PAP). As colheitas foram feitas nos seguintes momentos: M1 - 30 minutos após o início da anestesia inalatória antes da aplicação do opióide; M2 - 15 minutos após a administração da buprenorfina; M3, M4 e M5 - de 15 em 15 minutos após M2. A avaliação estatística dos dados foi efetuada por meio de Análise de Perfil (p<0,05). As variáveis PAS, PAM, DC, PVC e PAP, não apresentaram alterações significativas de seus valores em ambos os grupos. Entretanto, a FC e a PAD apresentaram reduções significativas após a administração do opióide apenas no GI. Assim, pôde-se concluir que a buprenorfina administrada pelas vias IV ou IM não interferiu nos índices cardiovasculares de forma a manifestar efeitos clínicos importantes em cães anestesiados com desfluorano.

Gastric emptying and gastrointestinal transit of liquid in awake rats is delayed after acute myocardial infarction.

The outcome of acute myocardial infarction (AMI) on gastrointestinal motor behavior was assessed in awake rats. Under anesthesia, they were submitted to thoracotomy followed or not by occlusion of the left coronary artery. Next day, they were gavage fed (1.5 ml) with phenol red in 5% glucose solution and sacrificed 10, 20, or 30 min later. Each subset consisted of 7 to 19 animals. Dye recovery in the stomach, proximal, mid, and distal small intestine was obtained by spectrophotometry. Infarcted left ventricle plus septum area was about 48.9 +/- 2.8, 55.1 +/- 6.7, and 54.1 +/- 8.1% (respectively, for 10-, 20-, and 30-min subsets). AMI increased gastric dye retention by 25.5, 51.3, and 65.1% (respectively, for 10-, 20-, and 30-min subsets), while it decreased mid small intestine retention at 30 min (45.3%) as well as distal retention at 10 min (90.5%) and 20 min (90%). A positive correlation (rS = 0.64) was found between infarcted area and gastric retention values at 10 min. AMI also increased (P < 0.05) central venous pressure values in all subsets (3.8 +/- 0.2 vs. -2.1 +/- 1.5, 1.4 +/- 0.1 vs. 0.5 +/- 0.2, and 1.6 +/- 0.4 vs. -0.2 +/- 0.3 cm H2O), while it decreased (P < 0.05) mean arterial pressure (95.0 +/- 2.6 vs. 110.0 +/- 3.9 and 106.0 +/- 2.0 vs. 113.0 +/- 3.0 mm Hg, respectively, at 10 and 30 min), and increased (P < 0.05) the 10-min heart rate values (429.6 +/- 11.3 vs. 374.0 +/- 19.8 bpm). Omeprazole pretreatment did not alter this phenomenon. In another group of rats, cardiac chemoreflex stimulation by i.v. phenylbiguanide increased gastric dye retention by 51.1%. In conclusion, AMI delays the gastric emptying and gastrointestinal transit of liquid in awake rats.

Bleeding during hepatectomy can be reduced by clamping the inferior vena cava below the liver

Background Control of blood loss is a crucial problem during hepatectomy. Bleeding from the inflow system can be controlled by the Pringle maneuver or selective vascular occlusion. Bleeding from the outflow system is closely related to central venous pressure (CVP). Therefore, in this study, we evaluated whether vascular outflow control by clamping the inferior vena cava (IVC) below the liver (IVC clamping) during hepatectomy is a safe and effective method to reduce blood loss and CVP. Methods We reviewed the outcomes of 103 consecutive patients whose CVP values were >5 cm H 2O and who had undergone right or left hemihepatectomy between 1995 and 2000. Forty-seven patients who underwent hepatectomy with IVC clamping (Group A) between 1998 and 2000 were compared with the previous 56 patients who underwent hepatectomy without IVC clamping between 1995 and 1997 (Group B). Results The CVP decreased by 3.7 cm H 20 after IVC clamping. Estimated blood loss was 910 mL in Group A and 1177 mL in Group B. ( P = .008) No severe renal or cardiovascular damage occurred after IVC clamping. Conclusions IVC clamping is very effective in reducing blood loss during hepatectomy when the CVP is elevated and cannot be reduced pharmacologically or by fluid restriction.

Anesthetic management and complications in living donor hepatectomy

A total of 112 living donor hepatectomies (LDHs) performed from October 1999 to April 2003 at Ege University Hospital Organ Transplantation Center were reviewed and perioperative anesthetic courses and complications were determined. There was no perioperative mortality. Mean duration of operations was 333 ± 77 minutes (range, 160 to 540 minutes) for right lobectomies and 277 ± 88 minutes (range, 150 to 500 minutes) for left lateral segment plus left lobe operations. The remnant liver volume ratios of the patients was 0.58 ± 0.16 (range, 0.30 to 0.91) after harvesting. Crystalloids, colloid infusions, and transfusions aimed to keep hematocrit >25%, central venous pressure (CVP) <5 mm Hg and to maintain a urine output >1 mL/kg −1 while nitroglycerin was infused (0.5 to 2.0 μg/kg −1h −1) when needed to allow fluid infusions freely without increasing the CVP values. No transfusion was needed for 91 patients (81%) and 21 right lobectomy patients needed transfusion of blood products. Initial mean hematocrit of 38.9 ± 4.9% (range, 27% to 50%) for all patients was found 31.5% ± 5% (21% to 44%) at the end of the operation. Albumin blood levels averaged 4.27 ± 0.49 g/dL −1 at the beginning and 3.28 ± 0.45 g/dL −1 after hepatic resection. Perioperative complications were one air embolism, postoperative systemic inflammatory response syndrome in one patient, transient but severe hemoglobinuria due to a predonated autologous blood transfusion in another, prolonged recovery for neuromuscular blocker overdose in one patient, and postoperative atelectasis in three patients, two of whom had pneumonia later while two other patients had pleural effusions. One required a drainage. Living donor hepatectomies were performed with acceptable complications in anesthetic management during this study. The operation provides us with an optimal liver segment without resulting in mortality.

Cardiovascular Changes During Multiple Vertebroplasty With and Without Vent-Hole

An experimental study of cardiovascular complications arising during vertebroplasty (VP) of multiple levels. To investigate the cardiovascular changes during multiple VP and whether a vent-hole has a preventive effect. An experimental study and clinical reports showed that fat embolism (FE) and acute hypotension occur during VP. There is the concern that these complications may worsen during VP of multiple levels. Vent-holes may prevent FE during VP. In twenty-two sheep, four vertebral bodies were augmented with polymethylmethacrylate (PMMA). In ten sheep, a vent-hole was drilled into the pedicle contralateral to the injection site. Heart rate, arterial, central venous and pulmonary artery pressure, cardiac output and blood gas values were recorded. The lungs were subjected to histologic evaluation at postmortem. The consecutive augmentation of four vertebral bodies with PMMA induced a cumulative FE that gradually deteriorated baseline mean arterial blood pressure (MABP) and blood gas values. The deterioration of MABP and change in blood gas values were attenuated, when a vent-hole was drilled. The amount of intravascular fat in the lungs after multiple VP (19%) was reduced when a vent-hole was drilled (9%). Surgeons should be aware of the potential cardiovascular complications during VP of multiple levels. In the clinical setting, a needle in the contralateral pedicle could be used to decompress the vertebral body during the injection of bone cement.

Hypotension associated with systemic aggregated anaphylaxis is not attenuated by a selective endothelin-A receptor antagonist, BQ 610, in rabbits in vivo.

The present study was done to investigate the role of endothelin-1 (ET-1) in hypotension and bronchospasm provoked by anaphylaxis in rabbits in vivo. Forty-five rabbits sensitized to horse serum were randomly allocated to five groups: Group 1 (n = 10) received 0.5 nmol x kg(-1) of ET-1; Group 2 (n = 10) received 0.5 nmol x kg(-1) of ET-1 and 200 nmol x kg(-1) of a selective ETA receptor antagonist, BQ 610, without anaphylaxis; Group 3 (n = 5) received 200nmol x kg(-1) of BQ 610 alone without anaphylaxis, Group 4 (n = 10) received normal saline alone before being antigen challenged to induce anaphylaxis; Group 5 (n = 10) received 200 nmol x kg(-1) of BQ 610 before antigen challenge. Mean arterial pressure (MAP) values were significantly different between Groups 1 and 2. Heart rate (HR), central venous pressure (CVP), dynamic pulmonary compliance (C(dyn)), and pulmonary airway resistance (R(L)) did not differ significantly between Groups 1 and 2. MAP values were significantly decreased compared with baseline in both Groups 4 and 5; however, the values were not significantly different between two groups. CVP values were significantly different between Groups 4 and 5 only at the 15-min time point following antigen challenge. HR, R(L), and C(dyn) values were not significantly different between Groups 4 and 5, nor were the survival rates. BQ 610 does not improve hypotension or survival rates in systemic aggregated anaphylactic rabbits in vivo, implying that circulating ET-1 may not play an important role in anaphylaxis, although direct proof of production of circulating ET-1 or activation of ETA receptors is lacking in this study.

An alternative to left ventricular volume reduction

Background: Left ventricular (LV) remodeling leading to ventricular dilatation is ultimately a maladaptative process according to the law of Laplace. To counteract the wall stress increase, a new concept of reducing the LV cavity radius by changing the LV globular shape to a bilobular one through the insertion of transventricular splints has emerged. This procedure is tested in a model of congestive heart failure. Methods: A bovine model was used ( n = 9). Following splint insertion through a sternotomy, boluses of 2 liters of crystalloid were injected. After every bolus, hemodynamic measurements were performed without and with the splints tightened to a 10% and 20% stress level reduction, respectively. Comparisons between the 3 measurements were performed with analysis of variance test ( p < 0.05). Results: Splint tightening significantly reduced right and left heart pressures for central venous pressure (CVP) >10 mm Hg (CVP: 14.7 ± 5.2, 12.1 ± 5, 10.6 ± 4.7 mm Hg, p < 0.001 for baseline, 10% and 20% stress level reduction, respectively; mean pulmonary artery pressure: 33.5 ± 4.7, 31 ± 4.4, 29.4 ± 5.1 mm Hg, p < 0.001; pulmonary capillary wedge pressure: 20.5 ± 2.8, 18.9 ± 3.3, 17.5 ± 3.1 mm Hg, p < 0.001). The same holds true for cardiac output (6.5 ± 1.6, 6.7 ± 1.4, 6.8 ± 1.7 liter/minute, p < 0.001), whereas heart rate and mean arterial pressure were not affected. The systemic and pulmonary resistances did not vary significantly throughout the procedure. Importantly, none of the hemodynamic parameters worsened at any stage with the splints. Conclusions: In this model, hemodynamic parameters are improved with the splints for higher values of CVP, supporting the concept of reshaping the remodeled LV. This technique has the potential to improve patients with congestive heart failure.

Variations in gastric compliance induced by acute blood volume changes in anesthetized rats.

The impact of acute volume imbalances on gastric volume (GV) was studied in anesthetized rats (250-300 g). After cervical and femoral vessel cannulation, a balloon catheter was positioned in the proximal stomach. The opposite end of the catheter was connected to a barostat with an electronic sensor coupled to a plethysmometer. A standard ionic solution was used to fill the balloon (about 3.0 ml) and the communicating vessel system, and to raise the reservoir liquid level 4 cm above the animals' xiphoid appendix. Due to constant barostat pressure, GV values were considered to represent the gastric compliance index. All animals were monitored for 90 min. After a basal interval, they were randomly assigned to normovolemic, hypervolemic, hypovolemic or restored protocols. Data were compared by ANOVA followed by Bonferroni's test. Mean arterial pressure (MAP), central venous pressure (CVP) and GV values did not change in normovolemic animals (N = 5). Hypervolemic animals (N = 12) were transfused at 0.5 ml/min with a suspension of red blood cells in Ringer-lactate solution with albumin (12.5 ml/kg), which reduced GV values by 11.3% (P<0.05). Hypovolemic rats (N = 12) were bled up to 10 ml/kg, a procedure that increased GV values by 15.8% (P<0.05). In the restored group (N = 12), shed blood replacement brought GV values back to basal levels in bled animals (P>0.05). MAP and CVP values increased (P<0.05) after hypervolemia but decreased (P<0.05) with hypovolemia. In conclusion, blood volume level modulates gastric compliance, turning the stomach into an adjustable reservoir, which could be part of the homeostatic process to balance blood volume.

Constrictive Pericarditis: Intraoperative Hemodynamic and Echocardiographic Evaluation of Cardiac Filling Dynamics

Constrictive Pericarditis: Intraoperative Hemodynamic and Echocardiographic Evaluation of Cardiac Filling Dynamics

Comparison of pulmonary artery and central venous pressure waveform measurements via digital and graphic measurement methods

Background: Techniques to measure pulmonary artery (PA) pressure waveforms include digital measurement, graphic measurement, and freeze-cursor measurement. Previous studies reported the inaccuracy of digital and freeze-cursor measurements. However, many of the previous studies were small and did not thoroughly examine the circumstances of when digital measurements might be inaccurate. Objectives: To compare digital measurements and graphic measurements of PA and central venous pressure (CVP) waveforms in patients with a variety of respiratory patterns, and to compare digital measurements and graphic measurements of CVPs in patients with abnormal or right ventricular waveforms. Methods: A total of 928 patients were enrolled in this study. Waveforms from the PA and CVP were collected from each patient. The monitor pressure value (digital measurement) printed on the recorded waveform was compared with the pressure value obtained by a graphic strip recording and measured by one of the primary investigators (graphic measurement). Results: Digital measurements were found to be inaccurate in measuring waveforms in all respiratory categories and in measuring right ventricular waveforms. PA diastolic values and CVP values were the most inaccurately measured waveforms. Digital errors of more than 4 mm Hg were common. Conclusion: There were instances in which the monitor’s digital measurement was substantially different from the graphically measured value. This difference has the potential to mislead interpretation of clinical situations. The monitor’s ability to occasionally give digital measurement values similar to the graphic measurements may lead to a false sense of security in clinicians. Because the accuracy of the monitor is inconsistent, the bedside clinician should interpret waveforms through use of a graphic recording rather than rely on the digital measurement on the monitor. (Heart Lung® 2001;30:26-38.)

Abstracts of literature

Abstracts of literature

Relationship between central venous pressure and bioimpedance vector analysis in critically ill patients.

To assess the relationship between central venous pressure values and bioelectrical impedance vector analysis (BIVA), which may be used as complementary methods in the bedside monitoring of fluid status. Cross-sectional evaluation of a consecutive sample. Intensive care unit of a university hospital. One hundred and twenty-one consecutive Caucasian, adult patients of either gender, for whom routine central venous pressure measurements were available. None. Central venous pressure values and impedance vector components (i.e., resistance and reactance) were determined simultaneously. Total body water predictions were obtained from regression equations according to either conventional bioimpedance analysis or anthropometry (Watson and Hume formulas). Variability of total body water predictions was unacceptable for clinical purposes. Central venous pressure values significantly and inversely correlated with individual impedance vector components (r2 = .28 and r2 = .27 with resistance and reactance, respectively), and with both vector components together (R2 = .31). Patients were classified in three groups according to their central venous pressure value: low (0 to 3 mm Hg); medium (4 to 12 mm Hg); and high (13 to 20 mm Hg). Three BIVA patterns were considered: vectors within the target (reference) 75% tolerance ellipse (normal tissue hydration); long vectors out of the upper pole of the target (dehydration); and short vectors out of the lower pole of the target (fluid overload). The agreement between BIVA and central venous pressure indications was good in the high central venous pressure group (93% short vectors), moderate in the medium central venous pressure group (35% normal vectors), and poor in low central venous pressure group (10% long vectors). Central venous pressure values correlated with direct impedance measurements more than with total body water predictions. Whereas central venous pressure values >12 mm Hg were associated with shorter impedance vectors in 93% of patients, indicating fluid overload, central venous pressure values <3 mm Hg were associated with long impedance vectors in only 10% of patients, indicating tissue dehydration. The combined evaluation of intensive care unit patients by BIVA and central venous pressure may be useful in therapy planning, particularly in those with low central venous pressure in whom reduced, preserved, or increased tissue fluid content can be detected by BIVA.

Short-term ACE inhibition has no effect on sodium and water excretion during PEEP ventilation

The short-term effect of intravenous (i.v.) angiotensin converting enzyme (ACE) inhibitor enalaprilat in 10 critically ill patients, being ventilated with positive end-expiratory pressure (PEEP), on sodium and water excretion was investigated. Mean arterial pressure (MAP) decreased. Heart rate and central venous pressure (CVP) did not change. Glomerular filtration rate (GFR), urine volume (V) and sodium excretion (UNaV) decreased in two patients with reduced MAP. GFR, V and UNaV increased in two patients with decreased MAP. No relation between changes in MAP and excretion was observed in six patients. ACE decreased in all patients. Plasma renin activity increased, aldosterone decreased, while atrial natriuretic peptide as well as antidiuretic hormone did not change. Enalaprilat did not facilitate sodium and water excretion during ventilation with PEEP. Decreased MAP indicates that the investigated patients were very dependent on their renin-angiotensin system to maintain systemic perfusion pressure. Base-line MAP and CVP values were no predictors of haemodynamic and excretory changes following acute ACE inhibition.

Microcirculation of a bulbar conjunctiva in calves with the total artificial heart: results of a long-term study

The aim of this work was to study the microcirculation in calves with total artificial heart (TAH) using the observation of the microcirculatory bed of bulbar conjunctiva. The examination were performed on 21 calves with total artificial heart and 8 controls. The microcirculatory bed was registered using the flash photographic method. In experimental calves after artificial heart implantation the microvasculature was studied two times in a week, to follow the pathophysiological changes in longitudinal periods until 100 days, between 100 and 200 days and after 200 days. For the evaluation we used the correlation analysis between arteriovenous diameter ratio (A/V ratio) and the values of central venous pressure (CVP). On the basis of our results we can conclude that during the survival period with TAH the morphological changes of conjunctival microvasculature occur. Our results showed the varicosities, serpentine-like forms and typical congestive changes of small vessels in bulbar conjunctiva. The correlation analysis showed the positive correlation between arteriovenous diameter ratio (A/V ratio) and central venous pressure (CVP) in the late phase of survival period between 100 to 200 days and over 200 days. The number of pathological changes of calves with artificial heart implantation.

Perioperative management of aneurysmal subarachnoid hemorrhage: Part 2. Postoperative management.

Perioperative management of aneurysmal subarachnoid hemorrhage: Part 2. Postoperative management.

Effect of pericardiocentesis on circulating concentrations of atrial natriuretic hormone and arginine vasopressin in dogs with spontaneous pericardial effusion

Factors regulating the secretion of atrial natriuretic hormone (ANH) and arginine vasopressin (AVP) have not been elucidated fully. In several studies the release of these peptides has been studied by inducing both increased atrial pressure and atrial distension. A few studies employ cardiac tamponade, allowing the effect of atrial pressure and atrial stretch to be studied separately. In eleven dogs with spontaneous cardiac tamponade the effect of pericardiocentesis on circulating concentrations of ANP and AVP was studied. Pericardiocentesis was followed by a prompt rise in (non-elevated) plasma ANH concentrations from 21.6 +/- 7.3 to 65.4 +/- 17.1 pmol/l (mean +/- SEM). The initially slightly elevated AVP concentration of 5.5 +/- 1.5 pmol/l declined following pericardiocentesis to 2.1 +/- 0.5 pmol/l. In three dogs the systolic arterial pressure was measured indirectly and the central venous pressure was measured with a fluid-filled catheter. Before and after pericardiocentesis arterial pressure readings did not change significantly. Central venous pressure values showed an immediate very steep significant decrease after centesis. It is concluded that ANH release is primarily regulated by stretch and not by atrial pressure, that plasma AVP concentrations are moderately elevated in cardiac tamponade and that in cardiac tamponade pericardiocentesis causes a rapid decline in plasma AVP concentration.

Hemodynamic Responses of the Venous System during Global Brain Ischemia Related to the Reflex Bradycardia in the Rabbit.

Global brain ischemia in anesthetized rabbits induces a pressor response, bradycardia, apnea, and a reduction in cardiac output. The bradycardia is virtually abolished by bilateral aortic denervation (ADN). To elucidate hemodynamic responses in the venous system and the role of bradycardia in these responses during brain ischemia, central venous pressure (CVP), femoral venous pressure (FVP), and circulation time (CT) of a dye in large veins were simultaneously measured before and after ADN. Cardiopulmonary blood volume (CPBV) and circulating blood volume (CBV) were also measured using a dye-dilution technique in separate experiments. Before brain ischemia, the value of CVP, FVP, mean arterial pressure (MAP), and heart rate (HR) were 0.2 +/- 1.2 cmH2O, 8.9 +/- 1.9 cmH2O, 76 +/- 16 mmHg, and 274 +/- 35 beats/min, respectively (n = 8, mean +/- SD). During brain ischemia, CVP, FVP, and MAP significantly increased to 5.8 +/- 2.6 cmH2O, 11.1 +/- 2.4 cmH2O, and 159 +/- 10 mmHg, respectively. HR decreased to 113 +/- 54 beats/min. After ADN, the changes of CVP, FVP, and HR evoked by brain ischemia were significantly suppressed to 2.4 +/- 1.6 cmH2O, 9.8 +/- 2.1 cmH2O, and 210 +/- 61 beats/min, respectively; however, the increase in MAP was not affected. During brain ischemia, CVP correlated negatively with HR, and positively with CT. CPBV tended to decrease and CBV significantly increased by 3.7 +/- 2.5 ml/kg from that before brain ischemia. It seems that the increased amount in CBV evoked by brain ischemia mainly exists in large veins. From these results we conclude that bradycardia is a major determinant of the blood volume in the cardiopulmonary system and prevents its overflow into pulmonary circulation during global brain ischemia in the rabbit when afterload to the left ventricle is extremely increased.

Plasma endogenous opioid levels in acute myocardial infarction patients, with and without pain.

Plasma levels of beta-endorphin, met-enkephalin and dynorphin were assessed in acute myocardial infarction (AMI) patients, with and without pain (group I: no pain, N = 12; group II: severe pain, N = 16). Plasma opioid peptide concentration was measured on admission to hospital (between 1 and 3 h after the myocardial infarction onset), at 7, 12, 24 h and at 2, 3 and 4 days. A transient increase in plasma beta-endorphin levels was found in AMI patients with severe pain, the levels normalizing within 12-18 h when pain had ceased. No changes in beta-endorphin concentration were observed in AMI patients without pain. Compared with healthy subjects, low levels of met-enkephalin were found in both groups of AMI patients throughout the study. Low levels of dynorphin were observed in patients with no pain while in the other patients initial low levels of dynorphin normalized when pain ceased. Blood pressure, heart rate and central venous pressure values were normal and did not correlate with plasma opioid levels. The results suggest that endogenous opioids do not affect pain in the early phase of myocardial infarction. The rise in beta-endorphin concentration observed in patients with severe pain seems to be induced by pain stress.

Radiologische Verlaufskontrolle der Thoraxorgane beim Intensivpflegepatienten

Correlation between chest radiographs and clinical indicators was studied in 212 patients in intensive care. 1. There was good correlation between raised pulmonary artery pressure and radiological signs of left heart insufficiency, but not with the value of central venous pressure. 2. Fever and leukocytosis nearly always precede radiological evidence of pneumonia; their persistence does not necessarily indicate persistent pneumonia. 3. Pneumonias, effusions, atelectases and emboli are more common on the right. 4. More than 70% of central venous catheters were incorrectly placed; most commonly, the catheter was placed too low. Life-threatening complications occurred in 1.3%.

Central Venous Pressure Monitoring for the Critically Ill in Zambia

The safety and value of central venous pressure (CVP) monitoring in 100 critically ill patients in Zambia was studied prospectively. There were six complications related to insertion, the only serious one being a hydrothorax which was recognized and treated. One patient developed catheter-related septicaemia. CVP measurement altered proposed fluid management in 19 cases, determined management in 31 in whom fluid status was uncertain and confirmed fluid therapy in 50. Additional benefits of central venous catheterization were drug infusion in 33 patients and venous access in 53. Technical problems during monitoring occurred in 54 cases and were due to kinking of the catheter, blockage or inadvertent removal. In our circumstances the risks of cannulation of central veins seem justified in selected patients but good nursing supervision of patients is necessary.