Search PubMed⌕ Search

Biomedical subjects

A Baraka

Publications and source records attributed to A Baraka.

At least 91 records · Page 5Linked to original sources
PubMed1994

Hypertonic saline prehydration in patients undergoing transurethral resection of the prostate under spinal anaesthesia.

Thirty-three patients undergoing elective transurethral resection of the prostate were allocated randomly to receive either 0.9% isotonic saline 7 ml kg-1 (16 patients), or 3% hypertonic saline 7 ml kg-1 (17 patients) as a preload before spinal anaesthesia. After spinal anaesthesia, the incidence of systolic arterial pressure < 75% of control value was greater in the normal saline group than in the hypertonic saline group. Also, the mean dose of phenylephrine required to maintain arterial pressure > 75% of the baseline value was significantly greater in the normal saline group than in the hypertonic saline group.

Adult↗
PubMed1994

Influence of surface cooling and rewarming on whole-body oxygen supply-demand balance.

The influence of moderate hypothermia induced by surface cooling was studied on haemodynamic variables and whole-body oxygen consumption in a 43-yr-old female undergoing clipping of multiple cerebral aneurysms. Decreasing oesophageal temperature to 32 degrees C lowered the whole-body oxygen consumption by about 40%. The decrease in oxygen consumption was matched by a proportional decrease in cardiac output. During the rewarming phase, there was a progressive increase in oxygen consumption, which was matched by a proportional increase in cardiac output. This resulted in a constant oxygen extraction ratio, as evidenced by oxyhaemoglobin saturation which remained constant at different body temperatures. While the temperature-corrected PVO2 decreased progressively with cooling, the temperature-uncorrected PVO2 remained constant at all body temperatures. Thus the use of temperature-uncorrected PO2 during hypothermia may simplify clinical interpretation because of our familiarity with normothermic PO2 values and the normothermic oxyhaemoglobin dissociation curve.

Adult↗
PubMed1994

Efficacy of the self-inflating bulb in detecting esophageal intubation. Does the presence of a nasogastric tube or cuff deflation make a difference?

BACKGROUND: The principle underlying the use of the self-inflating bulb in differentiating esophageal from tracheal intubation is that the trachea is held open by rigid cartilaginous rings, whereas the esophagus collapses when a negative pressure is applied to its lumen. This investigation was designed to test the efficacy of the bulb in detecting esophageal intubation in the presence of a nasogastric tube and after tracheal tube cuff deflation. METHODS: In anesthetized patients, the trachea and esophagus were intubated with identical tubes. The efficacy of the bulb was tested after a nasogastric tube was placed (group 1, n = 70) and after cuff deflation (group 2, n = 60) by a second anesthesiologist. RESULTS: In patients with nasogastric tubes (group 1), the anesthesiologists reported no reinflation of the compressed bulbs connected to tubes placed in the esophagus and immediate reinflation when connected to tracheally placed tubes in every case. In group 2, the determination of tube placement was correct in every case after cuff deflation. Mean (+/- SEM) negative pressures generated when compressed bulbs were connected to esophageally placed tubes were 57.8 +/- 0.48 mmHg (group 1) and 55.3 +/- 0.52 mmHg (group 2) and remained unchanged after the introduction of nasogastric tubes or after cuff deflation. CONCLUSIONS: These results confirm that a nasogastric tube or cuff deflation does not interfere with the reliability of the self-inflating bulb in detecting esophageal intubation and thus does not contribute to false positive results. Confirmation of tracheal tube placement by this simple method makes it ideal for use with other recognized methods both in and outside the operating rooms and enables physicians and emergency personnel to proceed with other resuscitative measures.

Adolescent↗
PubMed1994

Differential lung ventilation as an alternative to one-lung ventilation during thoracotomy. Report of three cases.

Investigation was carried out on three elderly patients undergoing thoracotomy. During one-lung ventilation using a Robertshaw double-lumen tube, the PaO2 decreased below 11.7 kPa despite ventilation of the dependent lung with 100% oxygen. Differential lung ventilation was then initiated by partial occlusion of the adapter limb to the nondependent lung, whilst maintaining unrestricted ventilation of the dependent lung. In the three patients, differential lung ventilation increased the PaO2 to 15-37.2 kPa. The increased PaO2 may be attributed to diffusion oxygenation via the partially inflated, nondependent lung. Differential lung ventilation can be used during thoracotomy whenever one-lung ventilation is followed by hypoxaemia, despite adequate ventilation of the dependent lung with 100% oxygen.

Adult↗
PubMed1994

End-tidal carbon dioxide tension during laparoscopic cholecystectomy. Correlation with the baseline value prior to carbon dioxide insufflation.

An investigation of end-tidal carbon dioxide tension changes was carried out in 19 healthy adult patients undergoing laparoscopic cholecystectomy. Following induction of anaesthesia, and throughout surgery, the end-tidal carbon dioxide tension was continuously monitored by capnography. The value following carbon dioxide insufflation increased with time to reach a maximum value after 40 min. Correlation of the individual maximum end-tidal carbon dioxide tension during laparoscopy with the corresponding baseline value prior to carbon dioxide insufflation showed a positive linear relationship (correlation coefficient 0.86). The correlation showed that an end-tidal carbon dioxide tension of 5.32 kPa (40 mmHg) can be achieved during laparoscopy when the baseline value is adjusted to around 4.0 kPa (30 mmHg).

Adult↗
PubMed1994

An audit of sickle cell screening in a paediatric hospital population.

Current UK guidelines for the detection of sickle cell disease (SSD) recommend pre-operative screening of patients of African or Afro-Caribbean descent and of patients from the Middle East, South Italy, Greece and India. These recommendations have considerable cost implications for the NHS. We have undertaken a retrospective audit of the use of SSD screening in our own institution. Between January 1987 and August 1992, 1305 patients under 15 years of age (mean 3.8 years) underwent screening for SSD. Surgical patients accounted for 1120 tests (85.8%). The majority of patients tested were of Asian descent (n = 955; 73%); only 350 (27%) were of African or Afro-Caribbean descent. Only four patients (0.3%) tested positive (all sickle cell trait); three of Afro-Caribbean descent and one from Bahrain. We conclude that, in our population, the incidence of HbS is low. Patients of African or Afro-Caribbean descent should continue to be tested but a selective policy may be indicated in other ethnic groups.

Adolescent↗
PubMed1994

Can pulse oximetry and end-tidal capnography reflect arterial oxygenation and carbon dioxide elimination during laparoscopic cholecystectomy?

An investigation was carried out on 13 ASA class 1 or 2 adult patients undergoing laparoscopic cholecystectomy. Throughout laparoscopy, the end-tidal PCO2 was continuously monitored by capnography and the arterial hemoglobin oxygen saturation by pulse oximetry. Also, repeated measurements of arterial blood gases were done. Ventilation was controlled using an inspired oxygen concentration of 33% and tidal volume of 10 to 15 ml/kg at a rate of 10-14/min. The report showed that both the mean end-tidal PCO2 and arterial PCO2 progressively increased following carbon dioxide insufflation, to reach a maximal value after 30 min, with no significant change in the arterial-alveolar PCO2 gradient. Also, the arterial PO2 significantly decreased, and the hemoglobin oxygen saturation was always above 98% whether monitored by arterial blood gas analysis or by pulse oximetry. The results suggest that end-tidal capnography and pulse oximetry can be used as noninvasive techniques for monitoring arterial oxygenation and carbon dioxide elimination during laparoscopic cholecystectomy.

Adult↗
PubMed1993

Jet ventilation in a case of tracheal obstruction secondary to a retrosternal goitre.

Intermittent jet ventilation was used during anaesthesia in a 66-yr-old woman who had severe tracheal narrowing secondary to compression by a retrosternal goitre. The trachea was intubated by a small-bore tube, which was placed above the site of narrowing. An injector was connected to the proximal end of the tracheal tube on one side and to the anaesthesia circuit on the other. Intermittent jets of 66% nitrous oxide in oxygen via the injector resulted in adequate oxygenation and carbon dioxide elimination. Arterial blood gas analysis during jet ventilation showed PaO2 150 mmHg, PaCO2 35 mmHg and pH 7.4. It is concluded that low-frequency jet ventilation may provide adequate oxygenation and carbon dioxide elimination in the presence of tracheal narrowing.

Aged↗
PubMed1993

A comparison of epidural tramadol and epidural morphine for postoperative analgesia.

The present study compared epidural tramadol with epidural morphine for postoperative analgesia in 20 patients undergoing major abdominal surgery. Intraoperatively, the patients were anaesthetized by a balanced technique of general anaesthesia combined with lumbar epidural lidocaine. In ten of the patients 100 mg tramadol diluted in 10 ml normal saline was also injected epidurally, while 4 mg epidural morphine was used in the other ten patients. In all patients, the visual analogue pain score, PaO2, PaCO2 and respiratory rate were monitored every hour for the first 24 hr postoperatively. In both the tramadol and morphine groups, the mean hourly pain scores ranged from 0.2 +/- 0.6 to 1.4 +/- 2.5 throughout the period of observations. However, the mean PaO2 was decreased postoperatively in the epidural morphine group, while no change was observed in the epidural tramadol group. The maximal decrease of PaO2 in the epidural morphine group was observed at the tenth hour postoperatively, when it decreased to 72.8 +/- 10.3 mmHg. This was not associated with any increase in PaCO2 or a decrease of respiratory rate, suggesting that hypoxaemia rather than hypercarbia or decreased respiratory rate may be an earlier indicator of respiratory rate, suggesting that hypoxaemia rather than hypercarbia or decreased respiratory rate may be an earlier indicator of respiratory depression in patients breathing room air without oxygen supplementation. The absence of clinically relevant respiratory depression following epidural tramadol compared with epidural morphine may be attributed to the different mechanisms of their analgesic action. The results suggest that epidural tramadol can be used to provide prolonged postoperative analgesia without serious side effects.

Abdomen↗
PubMed1993

Lidocaine cardioplegia for prevention of reperfusion ventricular fibrillation.

Lidocaine addition to crystalloid cardioplegic solution for prevention of reperfusion ventricular fibrillation after the release of the aortic cross-clamp was studied in 50 patients undergoing coronary artery bypass grafting and in 30 patients undergoing mitral or aortic valve replacement. Twenty-six of the patients undergoing coronary artery bypass grafting received lidocaine, 100 mg/L of cardioplegia, whereas a control group of 24 patients received cardioplegia without lidocaine. In the group undergoing valve replacement, 14 patients received lidocaine cardioplegia and 16 patients served as control. In the coronary artery bypass grafting group, lidocaine cardioplegia reduced significantly the incidence of reperfusion ventricular fibrillation from 100% to 42%. In the valve group, lidocaine cardioplegia also reduced significantly the incidence of reperfusion ventricular fibrillation from 93% to 42%. In both groups, lidocaine cardioplegia decreased the number of direct-current countershocks required to defibrillate the heart, with no significant increase in the incidence of high-grade atrioventricular block.

Cardioplegic Solutions↗