Biomedical subjects

H D Reines

Publications and source records attributed to H D Reines.

At least 37 records · Page 2Linked to original sources

PubMed1989

Conventional versus high frequency jet ventilation with a bronchopleural fistula.

A bronchopleural fistula (BPF) is an aberrant pathway through which inspired gas exits the lungs. A BPF may cause significant respiratory compromise, which in turn may result in the need of mechanical ventilation. The purpose of this study was to compare the efficacy of conventional positive pressure ventilation (CV) with high frequency jet ventilation (HFJV) using increasing increments of positive end expiratory pressure (PEEP) in the management of an induced BPF. A reproducible model of a BPF was surgically created in 10 mongrel dogs. Measurements of blood pressure (BP), cardiac output (CO), mean airway pressure (Maw), peak airway pressure (Paw), and fistula flow (FF) were carried out with the chest closed. Selective occlusion of the BPF allowed for blood gas stabilization at increased values of PEEP. Paired observations were performed at 0, 5, 10, 15, and 20 cm H2O of PEEP, while maintaining PaCO2 between 30 and 50 Torr. There was no difference in BP or CO between ventilation methods even though significantly lower Maw and Paw pressures were obtained using HFJV. While FF increased significantly with each increment of PEEP, there was no improvement in flows obtained using HFJV. This acute model of a BPF demonstrated that increasing PEEP dramatically increases FF irrespective of the method of ventilation.

Animals↗

PubMed1989

A prospective comparison of IMV and T-piece weaning from mechanical ventilation.

Two hundred (200) consecutive medical and surgical patients requiring mechanical ventilation were entered into a prospective randomized trial of weaning by either intermittent mandatory ventilation (IMV) or T-piece. Patients in these groups were of similar age and sex and had the same total ventilation time (TVT). The study design provided equal time for each weaning mode after specific criteria for oxygenation and ventilation were satisfied (PaO2 greater than 55 mm Hg on FIO2 less than 0.5; VE less than 12 L/min and two of the following four parameters: MVV greater than 2 VE, VT greater than 5 ml/kg, FVC greater than 10 ml/kg, NIF less than or equal to -20 cm H2O). Of the original 200 patients 165 were entered into the weaning phase; 35 patients were withdrawn prior to weaning due to the discretion of the attending physician or protocol error. Weaning time was not different between the IMV (5.3 +/- 1.2 h, mean +/- SEM) and T-piece groups (5.9 +/- 1.4 h, p = NS). Of the 165 patients, 155 (93 percent) were weaned successfully by protocol, 79 in the IMV and 76 in the T-piece group. Of 155 patients, 136 (88 percent) were weaned on the first attempt by protocol. Of the 19 who were not weaned, 11 were weaned successfully on the second and five on the third trial; three patients required three-day weans. We conclude that clinically stable patients who require short-term mechanical ventilation and meet standard bedside weaning criteria can be weaned efficiently by protocol using either IMV or T-piece techniques.

Adult↗

PubMed1989

The rat in sepsis and endotoxic shock.

Compared to the experimental studies, interpretation of eicosanoid levels in human sepsis is complicated by a large number of uncontrolled variables. Further clinical studies are needed to establish the relationship between the septic rat model and the human septic condition. The rat model is useful for uncovering fundamental pathophysiologic processes and should be useful in developing therapeutic interventions in human circulatory shock. Studies on the rat model offered the first indication that eicosanoids were involved in the shock syndrome (Cook et al., 1980). This led to clinical trials to determine the role of these mediators in human sepsis (Reines et al. 1982). The rat affords a model system which allows for pharmacologic manipulation and testing of a large number of hypotheses in a practical and cost effective manner. The recent evidence that leukotrienes are released during circulatory shock in the rat and that attenuation of this release alters the pathophysiologic outcome (Ball et al., 1986), lays the groundwork for future clinical studies. Finding that eicosanoids and leukotrienes are elevated in rat models of adult respiratory distress syndrome (Hammarstrom, 1983) has opened further new areas of clinical inquiry. Although rat models involving bolus endotoxin administration have not been predictive of the human septic syndrome, they have proven useful in the determination of the cellular sources and mechanisms of eicosanoid and leukotriene action. From the evidence presented, the septic shock rat model would seem to be the best model in predicting the outcome of therapies in human sepsis. Limited clinical trials have assessed the therapeutic efficacy of pharmacologic agents which alter eicosanoid and leukotriene metabolism in sepsis. In view of the continued high mortality of patients with septic shock and the failure of conventional therapies (Sprung et al., 1984; DuToit et al. 1985), further clinical and experimental studies are desirable.

Adrenal Cortex Hormones↗

PubMed1988

Complications of nasoenteric feeding tubes.

Small-bore, silicone nasoenteric feeding tubes are increasingly utilized in the critically ill patient to provide nutritional support. The metallic-weighted tips and stiffening introducing stylets create the potential for misplacement with potentially serious consequences. We have reported our experience with 14 patients who had inadvertent tube misplacement, resulting in complications that included pneumothorax, hydrothorax, empyema, mediastinitis, pneumonia, and esophageal perforation. The incidence of radiographically detected abnormal tube position was 1.3 percent. The presence of cuffed tracheostomy or endotracheal tubes did not prevent this occurrence. The institution of enteral feedings should, therefore, be performed according to strict guidelines which include radiographic confirmation of desired position before feedings are initiated, limited and supervised use of stylets, and a need for special precautions in patients who are obtunded or receiving intubated respiratory assistance.

Aged↗

PubMed1988

Comparison of bioimpedance and thermodilution methods for determining cardiac output: experimental and clinical studies.

The changes in electrical bioimpedance caused by the blood flow through a thoracic segment may be measured using a series of electrodes placed at opposing ends of this segment. Cardiac output (CO) is calculated by computer as the change in bioimpedance over time. This study was performed to determine the accuracy of bioimpedance CO (CObi) compared with standard thermodilution CO (COtd) in an animal model and in patients. COtd was determined using a thermodilution CO computer, and CObi was calculated with a bioimpedance computer in 10 dogs at baseline and at 5-minute intervals following the injection of 7 mEq of calcium chloride. A high correlation between COtd and CObi was observed (r = 0.91, p less than 0.001) over a range of 2.5 to 6 L/min. Thirty-three paired observations using the CObi and COtd methods were performed in 10 patients following elective coronary artery bypass surgery. A significant correlation between the two methods was determined with a CO range of 2.1 to 7.8 L/min (r = 0.77, p less than 0.001). CObi became inaccurate with severe tachycardia (pulse, 180/min), low CO, or frequent arrhythmias. These results indicate that this technique provides a continuous noninvasive method of determining CO that is comparable with thermodilution techniques. The technique of CObi holds promise for widespread use when continuous and noninvasive monitoring of CO is necessary.

Adult↗

PubMed1988

A new device for emergency percutaneous transtracheal ventilation in partial and complete airway obstruction.

Several methods of percutaneous transtracheal ventilation have been described for the immediate relief of upper airway obstruction when conventional methods fail. This study was conducted to determine whether a single percutaneously placed catheter introducer (Arrow Emergency Infusion Device [EID]) could provide access adequate for percutaneous transtracheal ventilation with standard ventilatory modalities in an obstructed airway. Ten mongrel dogs were anesthetized, intubated, and monitored (for pulse, blood pressure, ECG, and arterial blood gases). The endotracheal tube was occluded. When the dogs became hypoxic and hypercarbic, the Arrow EIDs were inserted transtracheally and the dogs were ventilated with either a Bear 1 Adult Ventilator or a Mapleson D system. Percutaneous transtracheal ventilation by the Arrow EID adequately ventilated dogs with controlled partial (95%) or complete airway obstruction from hypoxic and hypercarbic states. The ease of insertion, decreased associated complications, ability to ventilate with easily available devices, and use with complete airway obstruction make the EID an effective device for transtracheal ventilation.

Airway Obstruction↗

PubMed1988

Resuscitative thoracotomy: the effect of field time on outcome.

In the past 5 years, 72 moribund patients have undergone resuscitative thoracotomy (RT) at the Medical University of South Carolina: 62 patients underwent the procedure before the adoption of a policy of mandatory rapid transport (scoop and run) for penetrating and unstable victims of trauma by our EMS system (Group I). Group II is comprised of ten patients who underwent RT following adoption of this policy. Resuscitation was successful in three patients in Group I (4.8%) and there were only two survivors (3.2%). In contrast, resuscitation was successful in two of ten patients in Group II (20%) and there was one survivor (10%). Nineteen patients in Group I (31%) were in traumatic full arrest on the scene, all of whom died. Twenty-five patients in Group I (40%) had a measureable pulse and/or blood pressure when EMS personnel arrived at the scene and subsequently "died" before their arrival at the trauma center. RT was also uniformly unsuccessful in this subgroup. Eighteen patients in Group I (29%) suffered cardiac arrest following their arrival at the hospital. Three of these patients (16.6%) were successfully resuscitated and two (11%) survived to leave the hospital. There were four traumatic full arrests in Group II (40%) and all four died. Only two patients in Group II (20%) lost their vital signs in transport and both died. Four patients in Group II (40%) suffered cardiac arrest after arrival at the hospital. Two of these patients (50%) were successfully resuscitated and one left the hospital (25%).(ABSTRACT TRUNCATED AT 250 WORDS)

Emergency Medical Services↗

PubMed1988

Is advanced life support appropriate for victims of motor vehicle accidents: the South Carolina Highway Trauma Project.

There is continuing controversy over the use of Advanced Life Support (ALS) in the treatment of multisystem injury. In this study, performed to define the role of ALS in the management of motor vehicle accidents (MVA), 538 ambulance run reports (ARR) and hospital records of patients involved in MVA in South Carolina for 1983 were examined. Of these, 248 were reviewed in depth by a trauma review committee (TRC). Paramedics were present in 81% (93% urban, 80% rural) of cases. ALS crews averaged 24.8 minutes on the scene compared to 18.1 minutes for Basic Life Support (BLS). It took 6 minutes longer to transport rural patients than urban patients (15.7 vs. 9.6 min). Total EMS time (response, on scene, transport) was 46 +/- 20 minutes. Extrication increased on-scene time from 20.5 to 31.1 minutes. Endotracheal intubation attempts were 67% successful and IV's were placed in 88% of attempts. Thirty-two per cent of ALS patients demonstrated an increased blood pressure en route compared to 12% of BLS patients. The TRC felt prehospital care was beneficial in 85% of cases, while 11.7% had inappropriate or inadequate care. Resuscitation and ALS in MVA appears to be beneficial in the treatment of multisystem trauma in a rural state.

Accidents, Traffic↗

PubMed1987

Beneficial effects of ibuprofen in oleic acid induced lung injury.

Metabolites of arachidonic acid, particularly thromboxanes, have been implicated as mediators of lung injury. The formation of thromboxane A2 can be decreased by glucocorticoid steroids by inhibiting the enzyme phospholipase A2 or by ibuprofen which inhibits fatty acid cyclooxygenase. This study was performed to determine if ibuprofen, methylprednisolone, or a combination of both could improve the pulmonary injury induced by oleic acid. Five groups of dogs were instrumented with pulmonary artery and extravascular lung water (EVLW) catheters and ventilated with 100% O2. Serial determinations of hemodynamic and pulmonary parameters were performed before and after oleic acid infusion. Plasma immunoreactive thromboxane B2 (iTxB2) and ibuprofen levels were also determined. Oleic acid rapidly induced a significant pulmonary injury as evidenced by hypoxemia and increases in extravascular lung water. Plasma iTxB2 rose significantly in the control group receiving only oleic acid. Pulmonary function and hemodynamic parameters were not changed by ibuprofen infusion alone. Ibuprofen attenuated the oleic acid induced hypoxemia and increased EVLW but did not significantly reduce plasma iTxB2. Methylprednisolone did not prevent the increase in plasma iTxB2 and was less effective than ibuprofen in preventing hypoxemia and increases in EVLW. The combination of ibuprofen and methylprednisolone did significantly inhibit the production of iTxB2, however in combination they protected less against the hypoxemia and increased EVLW than either agent alone. These results indicate that ibuprofen may have a protective effect in oleic acid induced lung injury that is not mediated through the inhibition of fatty acid cyclooxygenase. The results are also further evidence that thromboxane is probably not a pathogenetic factor in oleic acid induced lung injury.

Animals↗

PubMed1987

Left-sided vena cava mimicking traumatic ruptured thoracic aorta.

Mediastinal widening on a chest X-ray associated with chest trauma is a sign of possible traumatic aortic rupture. This paper presents a case of left-sided vena cava which mimicked an aortic rupture on chest roentgenogram. Contrast CT scan demonstrated the anomaly as the cause of the abnormal plain film.

Aorta, Thoracic↗

PubMed1987

Pulmonary complications of acute spinal cord injuries.

The records of 123 consecutive patients admitted with spinal cord injury were examined for the presence of pulmonary complications. Forty-nine had tetraplegia and 23 had paraplegia; the remainder suffered a variety of neurological deficits. Multiple injuries were encountered in 36 patients. Fifty-three pulmonary complications were noted in 44 (35.7%) patients. The most common problems were atelectasis and pneumonia. There were 22 (18%) deaths. Fourteen deaths were related to pulmonary complications. The mean age of patients who died was 52 +/- 13 (SE) compared to 28 +/- 12 for survivors. A mean forced vital capacity (FVC) of 1127 +/- 410 cc in patients suffering respiratory difficulties compared to a FVC of 1865 +/- 85 cc in patients without complications (P less than 0.001). Oxygenation (PaO2 90 +/- 19 torr) was normal in patients without respiratory problems and was abnormal in patients developing problems (PaO2 76 +/- 30 torr; P less than 0.05). Twenty patients were treated with a rotating bed. The complication rate of patients on the bed was only 10%. In conclusion, respiratory problems remain a significant cause of morbidity and mortality in spinal cord injury. The forced vital capacity, blood oxygen tension, and age are predictors of pulmonary complications. The use of a multidisciplinary approach and a rotating bed may minimize these problems.

Adolescent↗

PubMed1986

Oral ciramadol: a new analgesic for postoperative pain.

Ciramadol, a new synthetic narcotic agonist-antagonist analgesic, was compared in 30 and 60 mg doses with pentazocine 50 mg, aspirin 650 mg, and placebo in the treatment of 153 patients with postoperative pain. All drugs were administered between six and 72 hours after surgery. Analgesic efficacy was assessed for six hours after study drug administration using verbal pain intensity, analog pain intensity, and verbal pain relief scales. Significantly (P less than .05) higher analgesic efficacy scores were seen with ciramadol 30 mg than with pentazocine 50 mg and placebo at most of the evaluation points. Doses of ciramadol 30 mg were significantly (P less than .05) more effective than aspirin 650 mg at several time periods, and ciramadol 60 mg was better than pentazocine and placebo at several evaluation times. The 30-mg dose of ciramadol was generally more effective than the 60-mg dose. The mean six-hour cumulative sum of pain intensity difference scores, total pain relief scores, and sum of pain analog intensity difference scores showed that the best analgesic response occurred in the ciramadol 30 mg group, followed by the ciramadol 60 mg, aspirin 650 mg, pentazocine 50 mg, and placebo groups. Side effects were rare and mild. There were no medically important changes in vital signs in any treatment group.

Adolescent↗

PubMed1986

Comparative clinical study of Sulbactam and ampicillin and clindamycin and tobramycin in infections of soft tissues.

A prospective, randomized, double-blinded study was undertaken to evaluate the effectiveness of Sulbactam (a new semisynthetic, injectable penicillanic acid sulfone) to inhibit beta-lactamase activity of bacteria in infections of the soft tissue. Sixty patients with documented soft tissue infections were prospectively randomized. One-half received 1 gram of Sulbactam per 2 grams of ampicillin every six hours. The other half received 600.0 milligrams of clindamycin every six hours and 1.5 milligrams per kilogram of tobramycin every eight hours. Patient groups were similar in age, sex, associated medical problems and bacteriologic flora of wounds. Sulbactam and ampicillin showed a 93 per cent cure rate or improvement as compared with 81 per cent in the clindamycin and tobramycin group. Eradication of organisms was better in the Sulbactam and ampicillin group (67 versus 35 per cent). Antibiotic activity of ampicillin was significantly augmented by the addition of Sulbactam. Of the 223 total bacteriologic isolates, 38 per cent were sensitive to ampicillin alone. Addition of Sulbactam improved sensitivity to 70 per cent. The Sulbactam and ampicillin combination is an effective combination for the treatment of soft tissue infections.

Adult↗

PubMed1986

Elective cholecystectomy for the patient with sickle cell disease and asymptomatic cholelithiasis.

Experience with elective cholecystectomy in ten patients with sickle cell disease and one patient with sickle-thalassemia from 1977-1984 was reviewed. In contrast to an earlier review from our institution, the current series had a low morbidity. This improvement is attributed to careful perioperative care, especially preoperative transfusion, hydration, and oxygenation. Because of the increasing longevity of sickle cell patients, because of the incidence of eventual significant complications of even asymptomatic cholelithiasis, and in order to simplify medical management by eliminating the diagnostic confusion between acute cholecystitis and sickle cell hepatobiliary crisis, the authors believe that elective cholecystectomy is to be recommended for the sickle cell patient with asymptomatic gall stones.

Adolescent↗

PubMed1985

The effect of drainage tube size on adequacy of percutaneous abscess drainage.

Fifty-one patients with documented abdominal abscess cavities were treated by percutaneous abscess and fluid drainage (PAFD). Drainage catheters made of various materials in sizes ranging from 5 through 18 French (Fr) were retrospectively studied and prospectively assigned to patients. No significant difference in the success or failure of PAFD as a function of these factors was found once an 8.3 Fr catheter with 0.045-inch diameter side-holes was reached; catheters larger than this were not associated with improved patient outcome. Failues of PAFD occurred primarily with the presence of phlegmonous collections and cavities with fistulous connection to bowel.

Abdomen↗

PubMed1985

Subclavian vein catheterization.

Massive fluid replacement is occasionally useful for resuscitation of severely injured patients. The use of MAST garment and the inability to obtain peripheral intravenous access may necessitate the use of infraclavicular subclavian cannulation. Two modifications of the standard subclavian technique have been described which enable quick access for infusion of large fluid volume and autotransfusion. The first involves the placement of multiple catheters in the same vein. The second method utilizes a modified Seldinger technique to place an 8 F. Swan-Ganz introducer into the subclavian vein. Complications are similar to those encountered when the standard subclavian technique is utilized.

Abdominal Injuries↗

PubMed1985

Dazoxiben in human sepsis and adult respiratory distress syndrome.

Levels of thromboxane B2 (TxB2), the stable metabolite of thromboxane A2, are elevated in human and experimental septic shock. The thromboxane synthetase inhibitor dazoxiben has improved survival and decreased pulmonary hypertension in experimental endotoxemia. A randomized prospective study of 10 patients with the clinical diagnosis of sepsis and early adult respiratory distress syndrome (hypoxemia, radiologic evidence of the syndrome, and intrapulmonary shunt greater than 20%) was performed to test the efficacy of dazoxiben in ameliorating the effects of human sepsis. Five subjects received dazoxiben and five received placebo. Dazoxiben, 100 mg, or placebo was injected intravenously every 4 hours for a maximum of 72 hours. Plasma immunoreactive TxB2 (iTxB2) levels were determined by radioimmunoassay. Before dazoxiben, the plasma iTxB2 level was 752 +/- 261 pg/ml (n = 5) and was reduced within 1 hour to 333 +/- 137 pg/ml. The plasma levels of iTxB2 remained significantly decreased with subsequent doses of dazoxiben and it was 201 +/- 67 pg/ml (n = 4) 60 hours after dosing. In contrast, placebo had no significant effect on plasma iTxB2 levels (n = 5) throughout the entire period of observation. Dazoxiben did not induce any significant changes in pulmonary or systemic vascular resistance, intrapulmonary shunting, clotting studies, or extravascular lung water. One of the five subjects in the placebo group died and two of the five subjects in the dazoxiben group died. We conclude that dazoxiben was safe and effectively lowered plasma iTxB2 levels in patients with sepsis and incipient adult respiratory distress symptom, but did not significantly alter the hemodynamic and pulmonary sequelae of established sepsis.

Adult↗

PubMed1985

Elevated plasma 6-keto-prostaglandin F1 alpha in patients in septic shock.

Central venous plasma concentrations of 6-keto-prostaglandin F1 alpha (PGF1 alpha), the stable hydrolysis product of prostacyclin (PGI2, a vasodilator and antiaggregatory metabolite of arachidonic acid), were determined in patients with septic shock. In eight nonsurvivors, the median plasma 6-keto-PGF1 alpha level was 229 pg/ml (range 31 to 21,998), compared to 30 pg/ml (range 22 to 194) in six survivors. In three control patients who were not septic or in shock, the levels were less than 4 pg/ml. This study demonstrates that human septic shock is associated with elevated plasma levels of 6-keto-PGF1 alpha, and raises the possibility that increased PGI2 formation may play a role in human septic shock.

6-Ketoprostaglandin F1 alpha↗