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J Heinze

Publications and source records attributed to J Heinze.

14 recordsLinked to original sources
PubMed1992

[Premedication in retrobulbar anesthesia. A blood gas analysis comparison of sublingual flunitrazepam and intravenous midazolam].

Benzodiazepines for sedation may decrease the PaO2, the arterial O2 saturation (SaO2), and the CO2 response more in the elderly than in the young. The purpose of this study was to assess changes in blood gases due to i.v. midazolam or sublingual flunitrazepam given as premedication in elderly patients for unilateral cataract surgery. METHODS. Fifty patients over 65 years of age with treated arterial hypertension and other co-existing diseases (ASA III-IV) were randomly assigned to have: (1) i.v. midazolam titrated until they became drowsy (17 patients; 2.85 +/- 0.84 mg [mean +/- SD]); (2) sublingual flunitrazepam (16 patients; 0.005 mg/kg); or (3) no sedation (17 patients; controls). On entering the operating theatre, the radial artery was cannulated and the first blood gas analysis was obtained. The premedication was then given. At 5, 10, 20, and 30 min after premedication, before and 10 min after retrobulbar block, before operation, 5 and 15 min after the beginning of the operation, 10 and 20 min after administration of 500 mg acetazolamide i.v. during the operation, and 10 and 20 min after the operation additional arterial blood samples were analysed (a total of 15 measuring points). Pulse oximetry, invasive blood pressure, and ECG were continuously monitored. All patients received oxygen 3 l/min during the operation by nasal cannula. Differences between the three groups were analysed by Student's t-test or U-test and a P value < 0.05 was considered significant. RESULTS. The patient demography, including duration of anaesthesia and operation, was similar in the three groups (Table 1). No significant differences were seen in heart rate, mean arterial pressure, PaO2, pulse-oximetric oxygen saturation (SpO2), base excess, or serum bicarbonate levels. The PaCO2 increased in patients after midazolam (P < 0.01) and flunitrazepam (P < 0.05) until the beginning of the operation compared with the control group (Fig. 3); 20 min after the operation there was still a significant difference between the midazolam group and the controls. SaO2 was significantly (P < 0.05) lower in the midazolam group 10 and 20 min after administration of premedication compared with the control group, but was within physiological limits (Fig. 5). Despite titration, 2 patients had severe respiratory insufficiency 3 min after midazolam: the SpO2 decreased below 85% and the paO2 below 55 mmHg. The paCO2 was higher (P < 0.05) in the midazolam group 10 min after acetazolamide compared with the controls. CONCLUSIONS. The results of the study show the potential hazards of i.v. midazolam in the elderly. If sedation is required for cataract surgery under local anaesthesia, we recommend sublingual flunitrazepam or the use of benzodiazepines with lower hypnogenic effects in the elderly. A thorough preoperative discussion of anaesthesia and the operation might be an adequate substitute for any premedication in high-risk patients; the best blood gas analysis results were obtained in the control group.

Administration, Sublingual↗
PubMed1992

[General anesthesia vs. retrobulbar anesthesia in cataract surgery. A randomized comparison of patients at risk].

Several studies comparing retrobulbar block (RB) and general anaesthesia (GA) for cataract surgery in the elderly have been published. Most of them were retrospective. Our prospective study was designed in order to determine the benefits or disadvantages using RB or GA. Arterial blood gases (ABG) and cardiovascular stability were explored in high-risk patients undergoing elective unilateral cataract extraction. METHODS. Forty patients over 65 years of age and with other co-existing diseases (ASA III-IV) were allocated randomly to receive either GA or RB. No premedication was given to either group of patients. On arrival in the anaesthetic room, a radial artery was cannulated for collection of blood samples and direct monitoring of the blood pressure. Pulse oximetry and ECG were continuously monitored in all patients, the end-expiratory CO2 (F(eexCO2)) only in the GA group. GA was induced with vecuronium 0.1 mg/kg and thiopentone 5 mg/kg; the lungs were ventilated with 100% oxygen. After intubation of the trachea controlled mechanical ventilation was continued with N2O/O2 (55:45) and enflurane 1%-2%. Only enflurane concentrations were varied to correct changes in mean arterial pressure (MAP) if these exceeded +/- 20%. Respiratory frequency and tidal volume were kept constant until completion of surgery. The patients were extubated when they were able to ventilate more than 5 1/min (pressure support 10 cmH2O; PEEP 5 cmH2O). After extubation no O2 was given. In the RB group neural block was undertaken with prilocaine 2% (3 ml) as a retrobulbar injection and prilocaine 1% (5 ml) to block the facial innervation of the orbicularis muscle (Van Lint, O'Brien). Oxygen 3 1/min was administered by nasal tube during the operation. Nine arterial samples for blood gas analysis were collected: (1) control; (2) before operation; (3) 5 min after beginning the operation; (4) 15 min after beginning the operation and before i.v. administration of 500 mg acetazolamide over 5 min; (5) after acetazolamide; (6 and 7) 10 and 20 min after acetazolamide; and (8 and 9) 15 and 30 min after operation (RB) or extubation (GA). RESULTS. The patient demography, including duration of anaesthesia and operation, was similar in both groups (Table 1). Four patients in the GA group (2 needed O2 after extubation because of hypoxaemia) and 2 in the RB group were excluded. No significant differences were seen in base excess (BE) and standard bicarbonate (SHCO3). Arterial O2 tension, arterial O2 saturation, and pulse-oximetric O2 saturation were higher in the RB group intra- and postoperatively (Figs. 1, 3, 4). Arterial CO2 tension (PaCO2) was significantly higher in the GA group during the pre- and postoperative period (Fig. 2), but not during the operation. The PaCO2- F(eexCO2) gradient ranged between 5 and 9 mmHg. Administration of acetazolamide did not influence this gradient by regressive analysis. The postoperative outcome of the patients was comparable in both groups. Nausea or vomiting did not occur. MAP was significantly higher in the RB group during the operation. No significant differences were seen in the pre- and postoperative period. Heart rate in the GA group was higher only after extubation, but was within physiological limits. DISCUSSION. Despite the differing results between the two groups, our study showed no important advantage related to either RB or GA. Changes in ABG, MAP, and heart rate during the investigation period were within physiological limits in elderly patients. Intravenous acetazolamide did not influence ABG in a significant manner. With regard to the preference of each patient, we recommend both RB and GA for cataract surgery in high-risk patients on the assumption of sufficient preoperative treatment of co-existing diseases. In conclusion, cardiovascular and ABG stability were maintained during both anaesthetic techniques.

Aged↗
PubMed1991

[A paracardiac sickle-shaped air mass following the insertion of a Swan-Ganz catheter--iatrogenic or caused by barotrauma?].

We report a 20-year-old male with severe injuries (head, multiple fractures, contusion of the left lung) who developed the adult respiratory distress syndrome (ARDS) on the 3rd day of treatment. The patient was ventilated as follows: FiO2 1.0; rate 14/min; minute ventilation 17 1/min; PEEP 10 cm H2O; peak inspiratory pressure 44 mmHg; mean pressure 31 mmHg. A Swan-Ganz catheter was inserted via the left subclavian vein. Because of dysfunction, this catheter had to be removed. A new Swan-Ganz catheter was inserted by the same route (no other central vein came into question because of massive swelling of the neck and inflammation of the skin). The post-cannulation chest radiograph showed bilateral paracardial air shadows for the first time. Two and 4 hours later the pneumomediastinum had diminished somewhat. During this time period the circulation and pulmonary function remained stable; no catecholamines had to be administered and artificial ventilation did not need to be changed. Post-mortem examination showed no injury to the trachea. It is concluded that the pneumomediastinum without subcutaneous emphysema was caused by a spontaneous mediastinal pneumothorax as a result of barotrauma at the time of insertion of a Swan-Ganz catheter.

Adult↗
PubMed1978

Microsurgery and lacrimal system.

Where epiphora results from canalicular obstruction, it is usually possible to cure the patient by reconstructing the canaliculi themselves. Resort to artificial bypass tubes is thus not often necessary. This paper discusses the role of the operating microscope in facilitating reconstruction of the lacrimal canaliculi so that longer segment of obstructed canaliculus can be reopened and more accurate reconstitution of the anatomy achieved. The place of fibre optics is outlined. Easier techniques for repairing lacerated canaliculi are described.

Dacryocystorhinostomy↗