Biomedical subjects

B M Wahlen

Publications and source records attributed to B M Wahlen.

7 recordsLinked to original sources

PubMed2006

[Structural damage of epidural catheters during combined spinal epidural anaesthesia: a lightmicroscopical study].

BACKGROUND: The purpose of this study was to investigate whether there is a risk of epidural catheter damage during the advancement of the spinal needle through an epidural needle in clinical use. METHODS: A total of 100 catheters (50 from CSE kits with a pencil-point type spinal needle and 50 from CSE kits with a Quincke type spinal needle) which had been used for routine CSE blocks were microscopically examined for any defects within the first 150 mm of the catheter. Additionally 10 unused new catheters were investigated. RESULTS: Among 10 unused catheters 5 slight scratches were found, 92 out of 100 used catheters did not show any signs of use or scratches, 7 showed some signs of use and longitudinal scratches whereas another 1 showed a moderate scratch of less than 25% of the wall thickness. There was no difference in the prevalence of scratches between the CSE kits with pencil-point type spinal needles compared to those with Quincke-type spinal needles. CONCLUSION: The CSE technique with either pencil-point type or Quincke-type spinal needles for subarachnoidal punctures was safe and showed no relevant epidural catheter damage.

Adult↗

PubMed2004

Three-dimensional cervical spine movement during intubation using the Macintosh and Bullard laryngoscopes, the bonfils fibrescope and the intubating laryngeal mask airway.

BACKGROUND AND OBJECTIVE: Cervical spine movement may be limited for morphological reasons or through injury. The major goal of the present study was to evaluate the three-dimensional cervical spine movement during intubation with a Macintosh or Bullard laryngoscope, a Bonfils fibrescope or an intubating laryngeal mask using an ultrasound-based motion system. METHODS: Forty-eight patients without any history of cervical spine problems who had to undergo elective surgery in general anaesthesia were intubated using a Macintosh or Bullard laryngoscope, a Bonfils fibrescope or an intubating laryngeal mask airway. During intubation, cervical motion as well as overall time to intubation, number of attempts, and postoperative complaints were noted. RESULTS: The range of cervical spine motion during intubation, especially concerning extension, using the Macintosh laryngoscope was much greater (22.5 degrees +/- 9.9 degrees) than using Bullard (3.4 degrees +/- 1.4 degrees), Bonfils (5.5 degrees +/- 5.0 degrees) or intubating laryngeal mask (4.9 degrees +/- 2.1 degrees). Time to intubate the trachea using Bonfils (52.1 +/- 22.0 s) and intubating laryngeal mask (49.8 +/- 18.7 s) were much longer than with Macintosh (18.9 + 7.1s) and Bullard laryngoscope (16.1 + 6.2 s) (significance level: 0.05). CONCLUSIONS: Our findings suggest that the Bullard laryngoscope may be a useful adjunct to intubate patients with cervical spine injuries. In elective situations when time to intubation is not critical Bonfils as well as intubating laryngeal mask airway should also be considered as serious alternatives to direct laryngoscopy.

Anesthesia, General↗

PubMed2004

Gastric insufflation pressure, air leakage and respiratory mechanics in the use of the laryngeal mask airway (LMA) in children.

BACKGROUND: The objective of the present study was to evaluate the prelaryngeal position of the laryngeal mask airway (LMA(TM)) in children, and to determine the influence of mask positioning on gastric insufflation and oropharyngeal air leakage. METHODS: A total of 100 children, 3-11 years old, scheduled for surgical procedures in the supine position under general anaesthesia were studied. After clinically satisfactory LMA placement, tidal volumes were increased stepwise until air entered the stomach, airway pressure exceeded 30 cmH(2)O, or air leakage from the mask seal prevented further increases in tidal volume. LMA position in relation to the laryngeal entrance was verified using a flexible bronchoscope. RESULTS: The insertion of the LMA with a clinically satisfactory position was achieved in all patients at the first attempt. Gastric air insufflation occurred in five of 49 patients with malpositioned LMA. No incident of gastric air insufflation was observed in 51 patients with correctly positioned LMA. The minimum inspiratory pressure leading to mask leakage was 17 cmH(2)O for incorrectly positioned LMA, and 25 cmH(2)O for correctly positioned LMA. Clinically unrecognized LMA malposition was associated with a significantly increased incidence of either oropharyngeal leakage (r = 0.59; P = 0.0001) or gastric insufflation (r = 0.25; P = 0.01). CONCLUSIONS: Clinically undetected LMA malpositioning is a significant risk factor for gastric air insufflation in children between 3 and 11 years, undergoing positive pressure ventilation, especially at inspiratory airway pressures above 17 cmH(2)O.

Air↗

PubMed2004

How long should patients refrain from oral food and fluid intake after general anaesthesia? An assessment of the swallowing reflex of postoperative neurosurgical patients.

OBJECTIVE: Our aim was to detect swallowing abnormalities in patients after short-term neurosurgical interventions under general anaesthesia, comparing patients with supratentorial operations with a group undergoing extracranial neurosurgery (nucleotomy). METHODS: 20 patients in each group were examined by fiberoptic endoscopic evaluation of swallowing (FEES) after general anaesthesia. RESULTS: No patient demonstrated dysphagia, aspiration, or oxygen desaturation. CONCLUSION: In these patient groups, early postoperative feeding was safe. Postoperative food intake can probably be allowed early after general anaesthesia.

Adult↗

PubMed2003

Measurement of end-tidal carbon dioxide in spontaneously breathing patients in the pre-hospital setting. A prospective evaluation of 350 patients.

OBJECTIVE: Monitoring of end-tidal carbon dioxide (EtCO(2)) is good clinical practice in the patient who is intubated and ventilated. This study investigated the EtCO(2) values in spontaneously breathing patients treated in a physician-staffed mobile intensive care unit (MICU). This article also discusses whether EtCO(2) monitoring may have an influence on therapeutic decisions by emergency physicians by providing additional information. METHODS: Over a period of 6 months, 350 spontaneously breathing patients (162 males, 137 females) were treated and transported in our MICU and monitored using a LifePak 12 monitor (EtCO(2), respiratory rate, pO(2), blood pressure, heart rate). Only 299 were enrolled in the study. RESULTS: Pathological EtCO(2) values were detected in 19 patients (6.3%). EtCO(2) levels of >55 mmHg (7.3 kPa) were found in nine of 12 (75%) patients with asthma, in one of 23 patients with hypoglycaemia (4.3%), and in all patients with subarachnoid hemorrhage, acute seizures and drug intoxications. With the exception of the asthma patients, all patients had an initial Glasgow Coma Score <8. EtCO(2) levels <20 mmHg (2.7 kPa) were found in all patients with hyperventilation or shock due to volume deficiency. Errors in EtCO(2) measurement occurred in 5% of cases. CONCLUSION: Although EtCO(2) monitoring may be a useful additional variable in spontaneously breathing patients. Consideration of the respective disease and the cost to benefit ratio suggests that this method should only be used for selected indications.

Adolescent↗

PubMed2003

[Initial medical treatment by paramedics in combined first aid operations of paramedics and emergency physicians].

OBJECTIVE: The present study was conducted to evaluate the quality of paramedic care and the feasibility and cost-effectiveness of sending a well-trained paramedic team to the sight of a medical emergency to initiate active medical treatment prior to the arrival of the mobile intensive care unit (MICU). METHODS: We examined 200 cases of medical treatment initiated by paramedics before arrival of the MICU team at the site of the medical emergency. Using a questionnaire, all emergency procedures performed by the paramedic team on scene were recorded and defined as "required", "carried out", and "accurately performed". The documented emergency procedures were divided into three categories: basic procedures (e. g. positioning, CRP, oxygen administration), additional procedures (e. g. placement of iv-lines, application of intravenous medication), and routine emergency diagnostic measures (e. g. monitoring of cardiopulmonary status). Further documented were the time of onset of emergency physician treatment, and the definitive transport vehicle used. To evaluate the time required for the measures performed, three different groups were identified according to the time gap between the arrival of the paramedic and the emergency physician teams (< 3 min, 3 - 5 min and > 5 min). RESULTS: In the 200 emergencies included in the study, 76 - 95 % of the required procedures were accurately performed prior to the arrival of the MICU team, at a success rate ranging from 87 to 100 %. CONCLUSIONS: In this study, a large number of emergency procedures could be performed by the paramedic team within a short period of time (in some cases < 3 min), and adequate effectiveness. Based on our results, the activation of paramedic-staffed first-tier ambulances with shorter response times is recommended in addition to the MICU system.

Allied Health Personnel↗

PubMed2001

[Anesthesia in ambulatory general practice].

Over the last years, ambulatory anaesthesia has gained more significance within the realm of anaesthesiology in Germany. The German health care system aspires to improve the link between ambulatory and clinical health care. Also, the increasing percentage of older people has changed the demographics of society considerably. As potential patients, older people tend to suffer from more pre-existing diseases than younger people, without necessarily being willing to forego ambulatory treatments. According to the guidelines of the "Bundesärztekammer", procedures in an ambulatory setting--and thus ambulatory anaesthesia--may not pose greater risks to patients than the same procedures performed in a clinical setting. The guidelines specifically include the pre-, intra- and post-operative care. This article reviews the guidelines of the "German Society of Anaesthesiology and Intensive Care Medicine" (DGAI) and other professional organizations with respect to ambulatory anaesthesia. It also reviews important structural and procedural requirements and recommendations for the implementation of ambulatory anaesthesia. Topics included are technical requirements, equipment, selection of patients, informed consent, fasting regulations, choice of anaesthetics and postoperative care. In order to accomplish a favourable outcome quality in ambulatory anaesthesia, professional judgement and implementation of the respective guidelines appear to be important rules of conduct.

Adolescent↗