The pattern of penetrating cardiac trauma in Basrah Province: personal experience with seventy-two cases in a hospital without cardiopulmonary by-pass facility.

A total of 72 patients with penetrating cardiac injuries were treated at Teaching Hospital in Basrah from February 1984 to July 1988. All patients were males, ages ranged between 18-40 years. 67 patients (93%) had sustained shell fragment injuries and 5 patients (6.9%) bullet wounds. 13 patients were unconscious on arrival and had no detectable pulse or cardiac activity and no obtainable blood pressure. Emergency room thoracotomy was employed in these patients. It restored cardiac activity in only one patient. 42 patients (58.3%) arrived with hypotension. 52 patients had one or more signs of heart tamponade (72.2%). The clinical triad of low blood pressure, central venous hypertension and distant heart sounds proved diagnostic in 73% of patients with heart injuries having tamponade. Pulsus paradoxus was found in 4% of the patients. Pericardiocentesis was of little value in diagnosis and treatment of cardiac tamponade and was not performed. The right ventricle was the most commonly injured chamber (44.4%). 56 patients (77.8%) presented with a normal sinus rhythm and 3 patients (4%) had an idioventricular rhythm. Patients with disorganised cardiac rhythm had a higher mortality (87%), than those with normal sinus rhythm (15%).     

Postganglionic Sympathetic Nerve Activity with Correlation to Heart Rhythm During Left Ventricular Assistance

In order to evaluate the effect of ventricular assist device (VAD) driving on the autonomic nervous system, sympathetic neurograms during left ventricular (LV) assistance were analyzed by power spectrum and coherence function. Our TH-7B pneumatically-driven sac-type VAD was used in seven adult mongrel dogs. VADs were inserted between the left atrium and the descending aorta. Renal sympathetic nerve activity (RSNA) was detected by use of bipolar electrodes attached to the left renal sympathetic nerve via a retroperitoneal approach. Values of squared coherence between the arterial pulse wave and RSNA were measured at the same frequency of cardiac and VAD pumping rhythms. During LV assistance, coherence at the cardiac rhythm frequency was decreased, and coherence at the VAD pumping rhythm frequency was increased. These results indicate that the arterial pulse wave, which was produced by the VAD assistance, contributed to postganglionic sympathetic nerve activity.     

Factors associated with cardiac rhythm disturbances in the early post-pneumonectomy period: a study on 259 pneumonectomies.

OBJECTIVE: To identify predisposing factors associated with cardiac rhythm disturbances during the early post-pneumonectomy period (first 7 postoperative days). MATERIALS AND METHODS: During the study period (1995-1999), 259 pneumonectomies were performed for malignant (244 cases) or benign disease (15 cases). Postoperative monitoring of patients included continuous arterial pressure - rhythm monitoring and pulse oximetry. Cardiac rhythm disturbances during the intensive care unit stay were detected on the monitor screen and recorded with a 12-lead electrocardiogram. Cardiac rhythm disturbances associated with electrolytes or fluid balance abnormality, mediastinal deviation or surgical postoperative complications were excluded from the study. Age of patients, preexisting cardiac disease, side of pneumonectomy, intrapericardial procedures, stage of the malignant disease, expected postoperative FEV(1)<1200 ml, intraoperative transfusions of packed red cells, elevated right heart pressures, low postoperative serum magnesium levels and long operative times were considered as predisposing factors for the development of post-pneumonectomy cardiac rhythm disturbances. Statistical analysis has been made using logistic regression analysis, Student t-test and chi-square test. RESULTS: Cardiac rhythm disturbances were detected in 49 patients (18.91%). Atrial fibrillation/flutter (31 cases), supraventricular tachycardia (14 cases), and premature ventricular contractions (four cases) were the observed rhythm disturbances. Right pneumonectomy versus left pneumonectomy (P<0.0001) and intrapericardial pneumonectomy versus standard pneumonectomy (P<0.0001) were identified as strong predisposing factors for the establishment of post-pneumonectomy cardiac rhythm disturbances. Patients who established post-pneumonectomy cardiac rhythm disturbances had significantly higher (P=0.024) right ventricular systolic pressure (42.50+/-15.50 mmHg) when compared with patients who had postoperative sinus rhythm (29.07+/-7.71 mmHg) and had also longer operative times than patients who did not develop rhythm disturbances (P=0.015). Mortality rate in patients who developed post-pneumonectomy rhythm disturbances was 20.40%. CONCLUSIONS: Cardiac rhythm disturbances observed early after pneumonectomy are mainly of supraventricular origin, complicating right and intrapericardial pneumonectomies, patients with elevated right heart pressures and long operative times, and are associated with high mortality rates.     

Implantation of bilateral deep brain stimulators in patients with Parkinson disease and preexisting cardiac pacemakers. Report of two cases

Deep brain stimulation (DBS) has become an important modality in the treatment of refractory Parkinson disease (PD). In patients with comorbid arrhythmias requiring cardiac pacemakers, DBS therapy is complicated by concerns over a possible electrical interaction between the devices (or with device programming) and the inability to use magnetic resonance imaging guidance for implantation. The authors report two cases of PD in which patients with preexisting cardiac pacemakers underwent successful implantation of bilateral DBS electrodes in the subthalamic nucleus (STN). Each patient underwent computerized tomography-guided stereotactic frame-based placement of DBS electrodes with microelectrode recording. Both extension wires were passed from the right side of the head and neck (contralateral to the pacemaker) to place the cranial pulse generators subcutaneously in the left and right abdomen. The cranial pulse generators were placed farther than 6 in from the cardiac pacemaker and from each other to decrease the chance of interference between the devices during telemetry reprogramming. Postoperative management involved brain stimulator programming sessions with simultaneous cardiological monitoring of pacemaker function and cardiac rhythm. No interference was noted at any time, and proper pacemaker function was maintained throughout the follow-up period. With bilateral STN stimulation, both patients experienced a dramatic improvement in their PD symptoms, including elimination of dyskinesias, reduction of "off" severity, and increase of "on" duration. With some modifications of implantation strategy, two patients with cardiac pacemakers were successfully treated with bilateral DBS STN therapy for refractory PD. To our knowledge, this is the first report on patients with cardiac pacemakers undergoing brain stimulator implantation.     

Circadian rhythms in systemic hemodynamics and renal function in healthy subjects and patients with nephrotic syndrome

BACKGROUND: The resemblance of the circadian rhythm of glomerular filtration rate (GFR) to that of arterial blood pressure (BP) suggests that systemic hemodynamic factors contribute to this variation. In the present study, this was investigated using continuous BP monitoring and pulse wave analysis. The study was performed in eight healthy subjects and in seven patients with nephrotic syndrome who had normal or reversed rhythms of GFR. METHODS: Circadian variations of renal function (continuous infusion of inulin/paraaminohippuric acid), noninvasive finger arterial pressure (Portapres), and vasoactive hormone levels were monitored during 27 hours. With stepwise backward regression analysis, the contributions of the measured variables to the circadian variation of GFR were investigated. RESULTS: Both groups showed a reduction of BP at night. In the controls, this was related to a drop in cardiac output, while in the patients, total peripheral resistance decreased at night. None of the hemodynamic variables explained the circadian GFR variation in both groups. In the controls, only 6% of the effective renal plasma flow (ERPF) rhythm was associated with variations in cardiac output (P = 0.03). In the patients, atrial natriuretic peptide and plasma renin activity were responsible for 36% of the variation in GFR (P < 0.01). CONCLUSIONS: These results indicate that the circadian variation of GFR does not result directly from changes in BP or cardiac output. An inverted GFR rhythm in patients with nephrotic syndrome may originate from hormonal mechanisms rather than directly from the hemodynamic effects of edema mobilization.     

Pulsatile Venoarterial Perfusion Using a Novel Synchronized Cardiac Assist Device Augments Coronary Artery Blood Flow During Ventricular Fibrillation

Patients with cardiogenic shock have a very high mortality. Here we report the first use of a percutaneous pulsatile cardiac assist device, based on a diagonal pump synchronized with the heart cycle by means of an electrocardiographic signal in adult pigs. Eight domestic pigs underwent mandatory ventilation. During sinus rhythm, there were no differences between pulsatile and nonpulsatile perfusion with regard to pulmonary artery pressure, pulmonary wedge pressure, central venous pressure, mean arterial pressure (MAP), mean pulse pressure, and mean coronary artery flow (CAF). After 2 min of complete cardiac arrest (ventricular fibrillation), circulatory support with the i‐cor in venoarterial nonpulsatile extracorporeal membrane oxygenation (ECMO) mode (3 L/min) restored systemic circulation, with an increase of MAP to 78.3 mm Hg and CAF to 5.27 mL/min. After changing from ECMO settings to pulsatile mode (3 L/min, 75 bpm, pulse amplitude range 3500 rpm), MAP did not change significantly (75.6 mm Hg); however, CAF increased to 8.45 mL/min. After changing back to nonpulsatile mode, MAP remained stable (83.6 mm Hg), but CAF decreased to 4.85 mL/min. Thereafter, pulsatile cardiac assist was established with a reduced blood flow of 2.5 L/min, and the pulse amplitude range was extended to 4500 rpm. Under these conditions, MAP remained stable (71.0 mm Hg), but CAF significantly increased to 15.2 mL/min (P < 0.05). Percutaneous cardiac support using a venoarterial cardiac assist device equipped with a novel diagonal pump is able to restore and increase systemic and coronary circulation during ventricular fibrillation. Electrocardiographically triggered synchronized cardiac assist provides an additional increase of coronary artery flow. These promising results are to be confirmed in humans.     

The results of prehospital cardiopulmonary resuscitation in the initial years of a mobile emergency care system

In this study the outcome of out-of-hospital cardiac arrest (CA) was analyzed during the first 3 years after installation of a mobile intensive care unit (MICU). The unit is staffed by an anesthesiologist as the emergency-care physician and specially trained health-care personnel. The success of cardiopulmonary resuscitation (CPR) was classified into three stages: (1) CPR with temporary cardiac output; (2) CPR primarily successful with spontaneous rhythm and a palpable pulse; (3) CPR, definitely successful resulting in the patient's discharge from the hospital without important neurological sequelae. All patients are grouped according to the disease underlying the CA. The performance of bystander CPR was recorded. The influence the factors sex, age, response time, cardiac rhythm, location of the collapse and period of investigation (1st year, 2nd year, 3rd year) had on the outcome was analyzed. RESULTS. Eighty-nine patients (32.96%) had a temporary cardiac output; 56 patients (20.74%) were primarily successfully resuscitated; and 12 patients (4.44%) survived without important neurological sequelae. Most of the diseases underlying the CA were in the internal disease group. Only 16 cases of bystander CPR performance were recorded. In the group with primarily successful CPR, significantly important factors arose with the increasing CPR success rate due to the period of investigation (1st year: 10.00%, 2nd year: 19.61%, 3rd year: 30.77%) and due to cardiac rhythm "ventricular fibrillation" (34.62%) and "asystole" (11.88%). Furthermore, significantly important factors were found for definite CPR success when comparing males (1.72%) and females (10.64%) and comparing the location of the collapse "in public places" (9.80%) and "at home" (2.00%). CONCLUSION. Our study shows that in spite of installing a MICU, the outcome of CPR is poor without supplementary measures. We consider that systematically teaching the public about basic life support measures and teaching medical students about emergency medicine will lead to a better CPR success rate in combination with continuing education of the MICU personnel.     

THE EFFECT OF TRICHLOROETHYLENE-NITROUS OXIDE ANAESTHESIA ON ACID-BASE BALANCE IN MAN

Thirty-five patients undergoing major operations under trichloroethyleneand nitrous oxide anaesthesia with muscle relaxants and withaugumented respiration in a Magill System (Mapleson A) or non-rebreathingsystem were monitored with regard to acid-base balance and ventilation.A trend to acidosis occurred with the Mapleson A system, particularlyin those in the prone position. A mild respiratory alkalosisoccurred when the non-rebreathing system was used. Acid-basebalance reverted to the pre-operative state early in the recoveryperiod and blood pressure, pulse and cardiac rhythm remainedrelatively stable throughout. This study indicates that trichloroethylenecan be a suitable anaesthetic for major surgery provided thatthe criteria enumerated in this report are fulfilled.     

The Use of Ungating with the Medstone Lithotriptor

Purpose

Ungating using the Medstone^* lithotriptor by 200 urologists was evaluated.

Materials and Methods

During 1994, 3,288 patients were treated by 200 urologists at 46 sites in 6 upper midwest states using 5 fixed and 3 mobile Medstone lithotriptors. Ungating was used with 58 treatments in 57 asymptomatic patients (1.8 percent) due to irregular cardiac rhythm in 48 caused by a bundle branch block (11), atrial fibrillation (10), slow heart rate (6) and irregular cardiac complex (21); all 48 cases were clinically insignificant, and because of urologist choice in 9 with normal cardiac rhythm (10 treatments). The cardiac simulator used for ungated lithotripsy was set at 85 shocks per minute for irregular cardiac rhythm and at 120 shocks per minute for elective use.

Results

The 48 treatments in patients with clinically insignificant irregular cardiac rhythm (average age 66.4 years) were performed during an average of 41 minutes of shock time. One patient had clinically significant cardiac arrhythmia that resolved with gating. The 10 elective treatments were performed during an average of 34 minutes of shock time in patients an average of 60.4 years old. The 3,231 gated treatments were performed during an average of 40 minutes of shock time in patients an average of 51 years old.

Conclusions

Ungating was safe and effective in allowing patients with an irregular cardiac rhythm to be treated with the same shock time as gated cases (normal cardiac rhythm).     

An evaluation of cardiac output by five arterial pulse contour techniques during cardiac surgery

The bias, precision and tracking ability of five different pulse contour methods were evaluated by simultaneous comparison of cardiac output values from the conventional thermodilution technique (COtd). The five different pulse contour methods included in this study were: Wesseling's method (cZ); the Modelflow method; the LiDCO system; the PiCCO system and a recently developed Hemac method. We studied 24 cardiac surgery patients undergoing uncomplicated coronary artery bypass grafting. In each patient, the first series of COtd was used to calibrate the five pulse contour methods. In all, 199 series of measurements were accepted by all methods and included in the study. COtd ranged from 2.14 to 7.55 l.min(-1), with a mean of 4.81 l.min(-1). Bland-Altman analysis showed the following bias and limits of agreement: cZ, 0.23 and - 0.80 to 1.26 l.min(-1); Modelflow, 0.00 and - 0.74 to 0.74 l.min(-1); LiDCO, - 0.17 and - 1.55 to 1.20 l.min(-1); PiCCO, 0.14 and - 1.60 to 1.89 l.min(-1); and Hemac, 0.06 and - 0.81 to 0.93 l.min(-1). Changes in cardiac output larger than 0.5 l.min(-1) (10%) were correctly followed by the Modelflow and the Hemac method in 96% of cases. In this group of subjects, without congestive heart failure, with normal heart rhythm and reasonable peripheral circulation, the best results in absolute values as well as in tracking changes in cardiac output were measured using the Modelflow and Hemac pulse contour methods, based on non-linear three-element Windkessel models.     

Sick sinus syndrome (SSS) after induction of anesthesia in a patient with increased intracranial pressure and ischemic heart disease

An 84-year-old male with increased intracranial pressure (ICP) and ischemic heart disease was scheduled to undergo brain tumor resection. After induction of anesthesia using midazolam, fentanyl and vecuronium, sinus bradycardia, junctional rhythm and escape-capture bigeminy were observed. In spite of intravenous administration of lidocaine and atropine, the bigeminy did not disappear. As he awoke from anesthesia, his cardiac rhythm changed from a bigeminal to a regular sinus rhythm. After extubation, sinus arrest, which continued for up to 4.8 seconds, appeared frequently. A temporary pacing catheter was inserted and ventricular pacing was started (mode VVI rate 50 min-1). Four days later, the patient was again scheduled to undergo brain tumor resection. After induction of anesthesia with the same drugs as used before, his cardiac rhythm gradually became bradycardic, and a complete pacing rhythm was observed throughout the surgical procedure. After the operation had been completed, his cardiac rhythm changed to a regular sinus rhythm. In addition to degenerative and ischemic changes in the SA node, an increase in ICP secondary to a brain tumor is thought to have induced sick sinus syndrome after the induction of anesthesia.     

Functional hemodynamic monitoring and dynamic indices of fluid responsiveness

Knowing whether or not a fluid infusion can improve cardiac output (fluid responsiveness) is crucial when treating hemodynamically unstable patients. Generally, cardiac filling pressures (central venous pressure, pulmonary artery occlusion ['wedge'] pressure) and volumes (end-diastolic left and right ventricular volume) are used, although they are not reliable predictors of fluid responsiveness. For this reason, new indices, the so-called dynamic indices of fluid responsiveness, have been recently introduced in clinical use. If stroke volume, or stroke volume-derived parameters (pulse pressure and aortic flow) show wide variation during mechanical ventilation, a good response to fluid therapy can be predicted. As these indices are based upon the effects of controlled mechanical ventilation on stroke volume, they can be used in deeply sedated or apneic patients whose cardiac rhythm is regular. To overcome these limitations, new dynamic indices have been introduced. Among them, variation of cardiac output induced by passive leg raising (PLR) has raised particular interest since it can identify fluid responders even among spontaneously breathing and non-sinus rhythm patients. Although promising, the dynamic indices of fluid responsiveness have been studied only retrospectively in a relatively small number of patients and evidence that clinical use of these indices can improve outcome is still limited. Further investigations are needed to confirm their clinical validity.     

A safe method for sedating and monitoring patients for upper and lower gastrointestinal endoscopy

Although the incidence of significant complications occurring during endoscopic procedures that require sedation are low, it has been demonstrated that they are usually related to cardiovascular system dysfunction. Such complications are a manifestation of cardiac hypoxia and are a function of the arterial oxygen desaturation. A practical method of monitoring such patients includes continuous oxygen saturation measurements and EKG monitoring. From October, 1987 to July, 1989, a total of 730 endoscopic examinations were performed using a combination of meperidine and midazolam as an intravenous (IV) bolus for sedation. Supplemental nasal oxygen was routinely given at 2 L per minute and real-time monitoring was performed with electrocardiograph and continuous pulse oximeter. There were no deaths and only four untoward events related to medication that altered the course of the examination. Transient hypoxemia that responds to gentle stimulation and bradycardia resolving with cessation of endoscope advancement are viewed as physiologic responses and not complications. All occurrences were immediately identified and corrected appropriately, and no morbidity resulted. With proper monitoring of oxygen saturation, pulse, and cardiac rhythm in a patient with nasal oxygen, IV bolus administration of meperidine and midazolam is a safe and adequate sedation even in the elderly and debilitated patient.     

Atropine before Enflurane Anaesthesia: Effects on Cardiac Rhythm, Pulse Rate, Blood Pressure and Airway Secretion

The occurrence of cardiac arrhythmias and changes in pulse rate and blood pressure during mask anaesthesia with enflurane was investigated in 92 patients with special reference to the influence of atropine (0.01 mg kg-1 5 min before anaesthesia) and thiopental. The average duration of anaesthesia was a little less than 1 h in all four groups. More than five ventricular extrasystoles occurred in one patient (38 min after atropine). Supraventricular (mainly nodal) arrhythmias were significantly (P less than 0.005) more common in the atropine groups (15/45) than in the non-atropine groups (4/47). Following atropine, heart rate increased by about 25 beats min-1, whereas only very slight increases were seen in the non-atropine groups. Blood pressure fell at the induction but was almost back to normal at the end of anaesthesia. Blood pressure was unaffected by atropine. Slightly lower values of blood pressure were suggested in the thiopental groups, whereas thiopental did not modify cardiac rhythm or pulse rate. Suction of the pharynx was necessary in only one patient. In conclusion, the present study does not support the routine administration of atropine before enflurane anaesthesia with or without thiopental induction.     

Effects of coronary grafting technique upon reperfusion cardiac rhythm, ventricular function, and other variables

The effects of different techniques of aortocoronary bypass grafting on reperfusion cardiac rhythm and ventricular function have not been systematically evaluated for possible advantages or disadvantages. The placement of proximal anastomoses before cardiopulmonary bypass and sequential coronary grafting with reperfusion via both the grafts and the native circulation were prospectively compared to traditional grafting and reperfusion via native arteries. More than 40 biochemical, thermal, temporal, hemodynamic, and other variables, including arrhythmias and myocardial failure, were measured intraoperatively and postoperatively. Spontaneous resumption of a cardiac rhythm occurred more frequently with traditional grafting technique in association with a larger cardioplegia volume and a higher serum potassium. However, the disadvantage of the traditional technique was a higher incidence of cardiac failure postoperatively and greater use of isoproterenol after discontinuation of bypass. While cardiac rhythm resumed spontaneously more often with the traditional technique, the increased incidence of cardiac failure postoperatively has serious implications. Thus, placement of proximal anastomoses before cardiopulmonary bypass seems warranted.     

Arrhythmias During Halothane Anesthesia IV. The Influence of a Single Dose of Suxamethonium

The effect of a single dose of suxamethonium on cardiac rate and rhythm during halothane anesthesia with babiturate induction was studied in a prospective, triple-blind trial with 28 patients. No atropine was given and patients were not intubated. A slight but significant preponderance of sinus-bradycardia without hemodynamic consequences was found in the group given suxamethonium. Suxamethonium did not provoke ventricular ectopies or conduction disturbances. It is concluded that in anesthesia with barbiturate induction, but without atropine or intubation, the use of a single dose of suxamethonium is a safe procedure with regard to cardiac rate and rhythm.     

慢性肾脏病患者血压非勺型节律与左心室肥厚之间的关系

目的 探讨24 h动态血压（ABPM）非勺型节律与慢性肾脏病（CKD）患者左心室肥厚（LVH）之间的关系。 方法 共有257例CKD 1~5期患者入选,根据肾功能分为两组：CKD1~3期组和CKD4~5期组。采用GE Marquette Tonoport V Eng动态血压计测定各组患者动态血压参数和昼夜节律;心脏彩色多普勒超声了解心脏结构的改变,并探讨血压非勺型节律与LVH之间的关系。 结果 CKD患者血压正常的生理节律丧失的现象普遍,总体血压非勺型昼夜节律发生率达75.4％,即使在血压正常者中也达到71.3%,随着肾功能下降血压非勺型昼夜节律的发生率也在上升。CKD患者血压非勺型节律组的心脏结构改变较勺型组明显,LVH的发生率也较高。相关性分析显示左室心肌质量指数（LVMI）与血压水平、非勺型的昼夜节律等相关。多元逐步回归分析显示24 h-收缩压（SBP）（β = 0.417,P < 0.01）、三酰甘油 （β = -0.132,P = 0.007）、血红蛋白（Hb）（β = -0.394,P = 0.016）及性别（β = 0.158,P = 0.039）是影响LVMI的独立危险因素。 结论 CKD患者的血压非勺型昼夜节律现象普遍,并随着肾功能的下降其发生率逐渐升高。血压非勺型节律患者心脏结构改变更明显,LVH的发生率高。非勺型节律与LVMI密切相关。     

Beat-to-beat measurement of cardiac output by intravascular pulse contour analysis: a prospective criterion standard study in patients after cardiac surgery

OBJECTIVE: To evaluate the accuracy of a new pulse contour method of measuring cardiac output in critically ill patients. DESIGN: A prospective criterion standard study. SETTING: Cardiac surgery intensive care unit in a university hospital. PARTICIPANTS: Nineteen cardiac surgery patients requiring intensive care treatment with pulmonary artery catheters after surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The pulse contour cardiac output monitor uses transpulmonary bolus thermodilution measurements to calibrate the system. In each patient, the pulse contour cardiac output values were compared with conventional thermodilution. The method described by Bland and Altman and linear regression analysis were used for comparison. The mean difference (bias) +/- standard deviation of differences (precision) was 0.31 +/- 1.25 L/min for pulmonary bolus thermodilution cardiac output versus pulse contour cardiac output and 0.21 +/- 0.73 L/min for pulmonary bolus thermodilution cardiac output versus transpulmonary bolus thermodilution cardiac output. Linear regression (correlation) analyses were pulse contour cardiac output = 0.97 thermodilution + 0.53 (r = 0.88), and transpulmonary cardiac output = 0.87 thermodilution + 1.09 (r = 0.96). There was a small increase 60 minutes after recalibration but not a statistically significant difference between pulse contour cardiac output and pulmonary bolus thermodilution cardiac output (p = 0.52). CONCLUSIONS: Bias and precision are acceptable, and the system provides results that agree with conventional thermodilution. This study demonstrates the clinical applicability of the pulse contour cardiac output monitoring system.     

Efficacy of nasal continuous positive airway pressure therapy in chronic heart failure: importance of underlying cardiac rhythm

BACKGROUND: Some previous reports have indicated beneficial cardiac effects of nasal continuous positive airway pressure (NCPAP) in patients with severe congestive heart failure (CHF), but others have reported deleterious cardiac effects, particularly among patients in atrial fibrillation (AF). The aim of this study was to determine if differences in cardiac rhythm influence the acute cardiac response to NCPAP. METHODS: Eleven consecutive patients with CHF were recruited, six in atrial fibrillation (AF) and five with sinus rhythm (SR). Cardiac index was measured during awake NCPAP application by the thermodilution technique during cardiac catheterisation. NCPAP was applied in a randomised sequence at pressures of 0, 5, and 10 cm H2O with three 30 minute applications separated by 20 minute recovery periods without NCPAP. RESULTS: Significant differences were found between the AF and SR groups for cardiac index responses to NCPAP (p = 0.004, ANOVA) with a fall in cardiac index in the AF group (p = 0.02) and a trend towards an increase in the SR group (p = 0.10). Similar differences were seen between the groups in stroke volume index responses but not in heart rate responses. Changes in systemic vascular resistance were also significantly different between the two groups (p < 0.005, ANOVA), rising in the AF group but falling in the SR group. CONCLUSIONS: These data indicate an important effect of underlying cardiac rhythm on the awake haemodynamic effects of NCPAP in patients with CHF.     

Penetrating cardiac trauma

During a 10 1/2 year interval ending in June 1980, 47 patients with penetrating cardiac trauma were managed at The University of Alabama Medical Center. Thirty-nine patients (83%) were male. Mean age was 31 years (range, 13 to 69). Thirty-two patients (68%) sustained stab wounds (SW) and 15 patients (32%) gunshot wounds (GSW). Forty-two patients (89%) arrived hypotensive (systolic blood pressure less than 90 mm Hg). Twenty-seven patients (57%) had evidence of cardiac tamponade (central venous pressure greater than 15 cm H2O) and 25 of these 27 patients were also in shock. Forty patients (85%) presented with a normal sinus rhythm and seven patients (15%) had an idioventricular rhythm or asystole. Overall mortality was 23% (11 of 47 patients). Forty-three per cent of the patients sustaining GSW (6/14) died compared to 17% (5/33) of the patients with SW (p = 0.04). Mortality for the patients in shock was 26% and for those with cardiac tamponade 15%. Mortality was 16% for the patients with both shock and cardiac tamponade. Thirteen per cent of the patients in normal sinus rhythm died, while 87% of the patients with idioventricular rhythm or asystole died (p less than 0.0001). Mortality in penetrating cardiac trauma remains high, particularly in patients with GSW and in those patients presenting with an idioventricular rhythm or asystole.