Cardiovascular responses to nitrous oxide exposure for two hours in man.

Cardiovascular responses to increasing (20, 40, and 60%) concentrations of nitrous oxide or nitrogen in oxygen for 15 minutes as well as responses to 2 hours of exposure to 60% nitrous oxide or nitrogen in oxygen were determined and compared in 30 healthy, supine, untrained volunteers who received no other drugs or medications. No concentration of nitrogen produced a significant change in any cardiovascular variable measured, nor did 20 and 40% N2O. Sixty percent nitrous oxide for 15 minutes significantly increased PaCO2, heart rate, stroke volume, cardiac output, mean arterial blood pressure, and central venous pressure.

Cardiovascular responses to clamping of the aorta during epidural and general anesthesia.

The cardiovascular responses of aortic cross-clamping and declamping with normal and high ventricular filling pressures were compared during epidural and nitrous oxide-morphine anesthesia in 32 male patients undergoing reconstructive aortic surgery. The patients were divided into four groups. Groups I and II had lumbar epidural blocks with bupivacaine and received nitrous oxide in oxygen to breathe; groups III and IV were anesthetized with morphine (2 mg/kg) and nitrous oxide.

The influence of blood flow and arterial blood pressure during cardiopulmonary bypass on deltoid muscle gas tensions and body temperature after bypass.

The results of this study demonstrate that skeletal muscle perfusion during bypass requires high flows and mean arterial pressures and that use of vasopressors during bypass impairs skeletal muscle blood flow. Our findings also indicate that skeletal muscle perfusion during bypass decreases metabolic acidosis after operation and prevents decreases in body temperature and poor skeletal muscle blood flow in the post-bypass and early postoperative periods. Our results suggest that perfusing to maintain normal Pmo2 during extracorporeal circulation is superior to more conventional techniques of conducting bypass.

Primary leiomyosarcoma of the aorta.

A case of primary leiomyosarcoma of the abdominal aorta is reported. The tumor replaced the full thickness of the aortic wall with formation of a large saccular aortic aneurysm filled with an admixture of tumor and mural thrombus. Electron microscopy of the surgical biopsy of the tumor revealed neoplastic smooth muscle cells with myofilaments and a discontinuous basal lamina.

Cardiovascular effects of fentanyl during enflurane anesthesia in man.

The cardiovascular effects of three doses of intravenous fentanyl (50, 100, and 200 microgram) were determined in 42 adult patients undergoing intraabdominal surgical procedures with enflurane (2--3%) and nitrous oxide (50%) in oxygen. Fentanyl was administered a minimum of 40 minutes after induction of anesthesia and 30 minutes after initiation of the surgical procedure. Stroke volume, heart rate, cardiac output, mean arterial and central venous blood pressures, and peripheral arterial resistance were determined by computer analysis of the central aortic pulse-pressure curve according to the method of Warner.

Fentanyl-oxygen anaesthesia for coronary artery surgery: cardiovascular and antidiuretic hormone responses.

This study demonstrates that large doses of fentanyl, as the sole anaesthetic with ventilation with oxygen, produces complete anaesthesia and minimal changes in cardiovasuclar dynamics in patients with coronary artery disease. It also indicates that high dose fentanyl anaesthesia blocks the increase in plasma anti-diuretic hormone and cardiovascular dynamics which are so common with morphine and other anaesthetic techniques during tracheal intubation and surgical stimulation in patients with coronary artery disease. Our findings suggest that fentanyl-oxygen anaesthesia is an attractive technique in patients with coronary artery disease.

Comparison of droperidol, haloperidol and prochlorperazine as postoperative anti-emetics.

The results of this study demonstrate that prochlorperazine, haloperidol and droperidol are all effective post-operative anti-emetic compounds when compared to saline but vary in onset of activity and duration of action. Haloperidol has the shortest onset of action, being effective within 30 minutes of intravenous administration. Prochlorperazine has an intermediate onset of action and droperidol is the slowest of the three compounds but the only one to provide significant anti-emesis 4-24 hours following administration.

Renal damage with intestinal bypass.

Renal function and biopsies were studied in 18 patients, 7 to 108 months after intestinal bypass. Enteropathy was found in 12 and hyperoxaluria in 16. Every biopsy showed a type of focal interstitial nephritis, tubular atrophy, fibrosis, and glomerular hyalinization.

Acute interstitial nephritis due to methicillin.

Fourteen patients are described with a syndrome of methicillin-induced interstitial nephritis. In all patients severe renal dysfunction developed with an average peak serum creatinine of 8 mg/100 ml. An increased total peripheral eosinophil count was found in all patients.

Patency of biologic and prosthetic inferior vena cava grafts with distal limb fistula.

A 5-cm segment of the infrarenal inferior vena cava (IVC) in 27 dogs was excised and replaced with a prosthesis of bovine heterograft, venous allograft, or polytetrafluoroethylene (ePTFE). On completion of the IVC graft, a side-to-side femoral arteriovenous fistula was constructed in the thigh. At six weeks an IVC venogram was obtained to assess patency and the femoral arteriovenous fistula closed.

Blood pressure and pulse rate responses to extubation with and without prior topical tracheal anaesthesia.

The results of this study demonstrate that 60 mg of lidocaine sprayed down the tracheal tube before extubation and 40 mg sprayed down the tracheal tube before extubation and 40 mg sprayed down during tracheal tube removal prevents increases in blood pressure and pulse rate during and after extubation. The data suggest that this manoeuvre should be of advantage to patients with coronary artery disease who may not be able to tolerate the increased cardiac dynamics which usually accompany extubation.

Tracheal pathology following short-term intubation with low- and high-pressure endotracheal tube cuffs.

Histologic sections of dog tracheas were taken from 20 dogs anesthetized and intubated for 5 to 7 hours with high-pressure, low-volume Shiley or low-pressure, high-volume Lanz endo-tracheal tubes. Microscopic examination and measurement showed that while the high-pressure, low-volume cuff produced deeper average mucosal erosion, the large-volume, low-pressure cuff resulted in significantly greater lengths of tracheal mucosa-cuff erosion. Maximal depth of penetration throught the basement membrane was similar in both groups.