Evaluation of the sternal intraosseous route as alternative emergency vascular access for the dental office: a manikin and cadaver model pilot study.

OBJECTIVE: To evaluate 2 sternal intraosseous access devices as alternatives to emergency intravenous access for dentists, using a manikin and a cadaver model. STUDY DESIGN: A group of 37 students performed a sternal intraosseous access on a manikin using a Vidacare kit including a puncture template and a prepuncture skin incision. Five months later, 9 of the students used the Vidacare and 8 used an Illinois needle (without template and incision) on adult human cadavers. India ink was injected as a tracer. RESULTS: Shorter times were recorded on cadavers compared with manikins in both systems. One Vidacare puncture ended subcutaneously. Two Illinois needle punctures perforated the sternum, one with intense mediastinal ink traces. Vidacare punctures took longer compared with Illinois needle punctures (medians, 32 vs 12 seconds; P = .0002). CONCLUSIONS: Template use to identify the sternal puncture position, combined with additional prepuncture skin incision, may be more efficient and less predisposed to severe complications for dentists' emergency use.

How delay to recompression influences treatment and outcome in recreational divers with mild to moderate neurological decompression sickness in a remote setting.

INTRODUCTION: This retrospective review examined the influence of delay to recompression on mild/moderate neurological decompression sickness (DCS) in divers, as a pilot for an abandoned prospective study. METHODS: The medical histories of 28 divers treated at a hyperbaric facility in the Maldive Islands in the Indian Ocean were evaluated. The term 'oxygen unit' (OU; 1 OU = 1 bar (ambient pressure) x 1 min x 1.0 (inspiratory oxygen fraction)) was used to enable a quantification of administered hyperbaric oxygen. Visual analog symptom scale (VASS) scores of the worst symptom at presentation (used routinely at the clinic to quantify treatment response) were analysed. RESULTS: Divers presenting later than 17 hours after surfacing (the median time to treatment after surfacing for the whole group) were likely to have more intense symptoms on VASS (median 100%) than those who presented earlier for treatment (median 30%, P = 0.02). Total OU needed to treat divers presenting within 17 hours did not differ from those treated later (P = 0.11). Divers with ≥ 70% symptom reduction with the first hyperbaric oxygen treatment (HBOT) needed between 260 and 1,463 OU in total, whereas those with less than 70% reduction in VASS needed between 263 and 2,126 OU (P = 0.04). CONCLUSIONS: Neither more HBOT nor a worse outcome of DCS could be related to delay to treatment longer than 17 hours. The amount of oxygen that had to be administered in total during the whole HBOT course was lower in cases that responded better to the initial HBOT.

Different reactions of human nasal and Eustachian tube mucosa after hyperbaric oxygen exposure: a pilot study.

Impairment of Eustachian tube function has been observed after hyperbaric oxygen treatment as well as after diving on oxygen used as breathing gas. The aim of the present study was to evaluate the influence of hyperbaric oxygen exposure on Eustachian tube ventilatory function and airflow characteristics of the nose. Six police task force divers performing two consecutive dives within a regular training schedule on oxygen were examined. Middle ear impedance, and nasal airflow velocities before and after diving as well as on the morning after the dive day were measured. Middle ear impedance decreased overnight in comparison to pre-dive values (P = 0.027) as well as compared to the value after the first dive (P = 0.032). Rhinoflowmetry did not reveal any changes of nasal airflow velocities related to the dives. Furthermore, no association between middle ear impedance and nasal airflow velocities was found. An impairment of Eustachian tube ventilatory function was obtained after hyperbaric oxygen exposure during dives employing oxygen as breathing gas. This impairment, however, was not associated with altered airflow characteristics of divers' noses. Thus, it seems unlikely that hyperbaric oxygen exerts an effect on the nasal mucosa similar to that on the Eustachian tube mucosa.

Comparison of clonidine and midazolam as anxiolytic premedication before wisdom tooth surgery: a randomized, double-blind, crossover pilot study.

PURPOSE: Anxiolytic and possible side effects of clonidine 150 µg compared to midazolam 7.5 mg for premedication in surgical wisdom tooth extraction were evaluated. METHODS: In a prospective, randomized, double-blind crossover trial, ten patients undergoing bilateral wisdom tooth surgery received clonidine or midazolam orally 1 h before the treatment. Patients receiving midazolam for the first surgery received clonidine at the second surgery and vice versa. The anxiolytic efficacy was evaluated with a visual analogue scale (VAS) upon admission and 30, 50 and 60 min after administration of the medication. Patient satisfaction was recorded on a VAS after surgery and 7 days postoperatively. RESULTS: As soon as 30 min after administration of midazolam (p < 0.03) and clonidine (p < 0.02), an anxiolytic effect was recorded. Both medications did not differ in patient satisfaction. CONCLUSION: Oral administration of clonidine 150 µg and midazolam 7.5 mg were rated as medications with equal anxiolytic effects before wisdom tooth surgery under local anesthesia.

Efficacy of ibuprofen versus lornoxicam after third molar surgery: a randomized, double-blind, crossover pilot study.

PURPOSE: The aim of this study is to compare the analgesic efficacy and tolerability of a pre-emptive/post-surgery 4-day regimen of oral ibuprofen 400 mg with that of lornoxicam 8 mg. METHODS: Sixteen patients received ibuprofen or lornoxicam, respectively, before and after surgery of impacted third molars in two separate appointments, in a double-blind, randomized, and crossover design. The postoperative analgesic and rescue medication consumption was recorded and pain scores were evaluated with a visual analogue scale at 2, 6, 24, 48, and 72 h, postoperatively. RESULTS: No statistically significant differences were found between ibuprofen 400 mg and lornoxicam 8 mg with respect to study medication (p = 0.34) or rescue analgesic consumption (p = 0.5) (SUMstudy and SUMrescue). Ibuprofen: SUMstudy median 7.5 interquartile range IQR (4.25-8), 95% CI (4.6-7.7); SUMrescue median and IQR 0, 95% CI (-0.6-4.6). Lornoxicam: SUMstudy median 7 IQR (3.75-9), 95% CI (7.7-4.9); SUMrescue median and IQR 0, 95% CI (-0.7-2.7). The area under the pain intensity curve (AUC(2-72) PI) over the 4 days of investigation did not reveal significant differences between the two medications (p = 0.32). AUC(2-72) PI ibuprofen: median 1,509.7 IQR (712.36-2,444.65); 95% CI (1,078.7-2,156.5). AUC(2-72) PI lornoxicam: median 1,166.9 IQR (783.4-2,221.2), 95% CI (1,032-2,130.6). Moreover, patient satisfaction and incidence of adverse events did not reveal any significant differences between treatment groups. CONCLUSION: Ibuprofen 400 mg and lornoxicam 8 mg were rated as equal and effective pain treatment medication after wisdom tooth surgery. In comparison, neither of the drugs provided clinical advantages nor did side effects occur more frequently after one of the analgesics.

[Dental surgery in patients receiving anticoagulant therapy]. / Zahnärztliche Eingriffe bei antikoagulierten Patienten.

It has long been a standard procedure to replace coumarin by heparin if a patient using this oral anticoagulant had to undergo dental surgery. The Quick-Value had then to exceed a certain limit before surgery could be safely performed. Today this procedure has changed in that a switch to heparin is only made for invasive and large area surgery. Simple dental extractions, small biopsies and periodontal treatments are performed under continuous oral anticoagulation and local hemostyptic measures are applied. It has been shown that the likelihood of postoperative bleeding complications after adequate local hemostasis during dental surgery is much lower than is the risk of thrombosis or embolic complication following cessation of anticoagulant medication before surgery.

[Prophylactic and therapeutic use of antibiotics in dental medicine]. / Präventiver und therapeutischer Einsatz von Antibiotika in der Zahnheilkunde.

In dentistry antibiotics are used as a prophylactic measure as well as for therapeutic reasons. For the general practitioner, antibiotic prophylaxis of infectious diseases of dental or oral origin is more prevalent than the antibiotic treatment of such infections. Patients suffering from bacterial infections of oral origin should be referred to a dentist or to an oral surgeon. This review aims to precisely describe the indications for antibiotic preventive measures before dental or oral surgical treatments. Theses measures should be commonly planned by the general practitioner and the dentist. The actual treatment of the infection should, however, be left to the dentist, oral or maxillofacial surgeon.

Comparison of different flow-reducing bag-valve ventilation devices regarding respiratory mechanics and gastric inflation in an unprotected airway model.

OBJECTIVE: Gastric inflation (GI) is a significant issue when ventilation is performed on unprotected airways. DESIGN: Experimental analysis on the respiratory effects of hose extended bag-valve ventilation devices designed to reduce inspiratory pressure and flow. SETTING: Laboratory with lung/oesophageal sphincter simulator and pressure-flow-volume analyser. Lung compliance: 300ml/kPa, airway resistance: 0.5kPa/l/s. Lower oesophageal sphincter pressure (LOSP): 0.5kPa. INTERVENTIONS: Bag-valve ventilation of lung simulator. Twelve academic dental staff members used four devices: Ambu Mark III attached to either a reservoir bag (R) or a pressure relief valve (SV), SMART BAG (SB), and Easy Grip (EG) as control. RESULTS: After Bonferroni correction (p-level of significance 0.0083) for multiple comparisons, no evidence of difference between inspiratory tidal volumes (TVIN) administered by use of R (median 137ml) and SB (149ml) was found. Differences in TVIN were only detected between R and SV (188ml) (p=0.002). Only a trend towards TVIN differences between SB and R in comparison to EG (195ml) was found (p=0.009). Distributions of peak pressures differed when R (median 0.7kPa) and SV (1.0kPa) (p=0.006) or SB (0.7kPa) and SV (p=0.002) were compared. Peak inspiratory flow rates differed between EG (median 59l/min) and R (32l/min) as well as SB (42l/min) and between SB and SV (50l/min) (all with p=0.001). GI was lowest by use of R (median 103ml) compared to all other devices (EG: 518ml, SV: 394ml, SB: 271ml) (p=0.001). The areas under the pressure/flow over time curves were larger during SB compared to R ventilation. Mean airway pressures were significantly lower by use of R (0.1kPa) compared to SB (0.3kPa) (p<0.008). CONCLUSION: Lowering GI by pressure-flow reduction may result in lower TV depending on the device used. Lowest GI resulted from R ventilation. This may be explained by the specific pressure/time or flow/time patterns achieved by use of this device.

Alternative concept of ventilation during cardiopulmonary resuscitation (CPR) in dental chairs.

Infrequent training of artificial ventilation in dental facilities implies poor performance of this procedure under CPR. Gastric inflation is a significant issue when ventilation is performed on an unprotected airway. An Easy Grip (EG) Bag-Valve-Mask Resuscitator, a Laryngeal Tube (LT), size #5, and a SMART BAG (SB) resuscitator, a pressure-limiting device, were tested to assess the respiratory effects especially focussing on prevention of gastric inflation during simulated CPR. Twenty academic dental staff members performed ten ventilations on a manikin during CPR by use of EG, LT and SB in a randomized order. In twelve experiments the oesophageal sphincter pressure was adjusted to 15 mbar (best case), in eight experiments to 0 mbar (worst case scenario). Best case scenario median tidal volume distributions achieved by EG (median 144 ml) and LT (75 ml) did not differ, whereas differences were found between EG and SB (31 ml; p = 0.055) as well as between SB and LT (p = 0.042). None of the values met recommended ranges. Almost no gastric inflation occurred. Worst case scenario ventilation by use of the LT resulted in profoundly lower median gastric inflation volumes (median 13 ml) compared to SB (median 288 ml; p=0.008) and EG (800 ml; p = 0.008). Median tidal volume distributions also differed between LT (225 ml) vs EG (100 ml) (p=0.016) and LT vs SB (19 ml) (p =0.008). Chest compression was delayed in ten experiments by LT insertion for 28 s (median). In a later stage of CPR or in case of mask ventilation difficulties, the LT may serve as a helpful tool in dental facilities. CPR training must focus on the importance of chest compression which must not be discontinued if an LT is inserted. The SB might gain value if higher tidal volumes are achieved, exerting a higher risk of gastric inflation.

Mechanical impedance of the respiratory tract in divers before and after simulated deep dives.

Previous studies have inconsistently shown changes in expiratory flows and volumes as well as diffusion capacity of the lungs after single dives and several diving related occupational conditions were considered as possible underlying factors. In this study mechanical impedance of the airways was measured before and after simulated dives to non-invasively determine whether there is evidence for lung function impairment due to hyperbaric exposure. Thirty-three healthy male divers employing air self-contained underwater breathing apparatus were randomly assigned to dry and wet chamber dives in a cross-over design to 600 kPa ambient pressure (total duration 43 min, bottom time 15 min, water temperature 24 degrees C). Immediately before and after diving, oscillometric parameters-e. g. resistance and reactance of the respiratory tract-were measured at defined frequencies (5, 20 Hz). Spirometry was carried out as well (FVC, FEV(1), MEF 25-75). No significant changes between post-exposure values and baseline values were detected by respiratory impedance and spirometry. Diving in accordance to diving regulations and without excessive workload is not a source for acute obstructive lung function changes as the obtained oscillometric data suggested. Moreover this study could not confirm changes in spirometry after simulated diving exposure.

[Clonidine in oral medicine. Literature review and our experience]. / Clonidin in der Zahn-, Mund- und Kieferheilkunde. Literaturübersicht und eigene Erfahrungen.

There is a large experience in premedication with clonidine (Catapresan) for general anaesthesia. Clonidine is an alpha2-adrenoceptor agonist exerting central sympatholytic effects. Premedication with clonidine blunts the stress response to surgical stimuli and the narcotic and anaesthetic dose can be reduced. Furthermore, perioperative myocardial ischemic events can be prevented by preoperative application of clonidine. Oral clonidine at a dose of 1.5-2 microg/kg BW combines the advantages of benzodiazepines and morphine: anxiolysis, sedation and analgesia with stable hemodynamics and respiration. Clonidine does not have morphine related side effects such as nausea and vomiting. Doses of up to 5 microg/kg BW have been administered to young and healthy patients preoperatively in dental and maxillofacial surgery without significant side effects. However, Clonidine 2 microg/kg BW should be an adequate oral premedication dose for young and healthy patients scheduled for dental and facial surgery procedures performed under local anaesthesia in the ambulatory setting. In elderly patients clonidine 2 microg/kg BW administered orally should not be exceeded to avoid excessive hypotension and sedation. Bradycardia is a contraindication for the use of clonidine.

Leukotriene-B4 concentrations in exhaled breath condensate and lung function after thirty minutes of breathing technically dried compressed air.

In previous studies it had been shown that leukotriene-B4 [LTB4] concentrations in the exhaled breath mirror the inflammatory activity of the airways if the respiratory tract has been exposed to occupational hazards. In diving the respiratory tract is exposed to cold and dry air and the nasopharynx, as the site of breathing-gas warming and humidification, is bypassed. The aim of the present study was to obtain LTB4-concentrations in the exhaled breath and spirometric data of 17 healthy subjects before and after thirty minutes of technically dried air breathing at normobar ambient pressure. The exhaled breath was collected non-invasively, via a permanently cooled expiration tube. The condensate was measured by a standard enzyme immunoassay for LTB4. Lung function values (FVC, FEV1, MEF 25, MEF 50) were simultaneously obtained by spirometry. The measured pre- and post-exposure LTB4- concentrations as well as the lung function values were in the normal range. The present data gave no evidence for any inflammatory activity in the subjects' airways after thirty minutes breathing technically dried air.